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Journal of Clinical Oncology, Vol 18, Issue 2 (January), 2000: 275
© 2000 American Society for Clinical Oncology

Pilot Trial of the Safety, Tolerability, and Retinoid Levels of N-(4-hydroxyphenyl) Retinamide in Combination With Tamoxifen in Patients at High Risk for Developing Invasive Breast Cancer

By Barbara Conley, Joyce O’Shaughnessy, Sheila Prindiville, Julia Lawrence, Catherine Chow, Elizabeth Jones, Maria J. Merino, Muriel I. Kaiser-Kupfer, Rafael C. Caruso, Marvin Podgor, Barry Goldspiel, David Venzon, David Danforth, Suhlan Wu, Marianne Noone, Jennifer Goldstein, Kenneth H. Cowan, JoAnne Zujewski

From the Greenebaum Cancer Center, Divisions of Hematology and Oncology, and Department of Medicine, University of Maryland School of Medicine, Baltimore; Medicine Branch, Laboratory of Pathology, and Surgery Branch, Division of Clinical Sciences, National Cancer Institute (NCI); Pharmacy Department, Department of Radiology, Warren Grant Magnusen Clinical Center; and National Eye Institute, National Institutes of Health, Bethesda, MD.

Address reprint requests to JoAnne Zujewski, MD, Medicine Branch, Rm 12N226, Bldg 10 (Clinical Center), NCI, NIH, 9000 Rockville Pike, Bethesda, MD 20892; email zujewski{at}nih.gov


    ABSTRACT
 TOP
 ABSTRACT
 INTRODUCTION
 PATIENTS AND METHODS
 RESULTS
 DISCUSSION
 REFERENCES
 
PURPOSE: N-(4-hydroxyphenyl) retinamide ([4-HPR], Fenretinide; R.W. Johnson Pharmaceutical Research Institute, Springhouse, PA) and tamoxifen (TAM) have synergistic antitumor and chemopreventive activity against mammary cancer in preclinical studies. We performed a pilot study of this combination in women at high risk for developing breast cancer.

PATIENTS AND METHODS: Thirty-two women were treated with four cycles of 4-HPR, 200 mg orally (PO) for 25 days of each 28-day cycle, and TAM, 20 mg PO once daily for 23 months beginning after 1 month of 4-HPR alone. Tolerability, dark adaptometry, tissue biopsies, and retinoid plasma concentrations (Cp) were evaluated.

RESULTS: Symptomatic reversible nyctalopia developed in two patients (6%) on 4-HPR, but 16 (73%) of 22 patients had reversible changes in dark adaptation, which correlated with relative decrease in Cp retinol (P <= .01). Four patients stopped treatment for side effects, and 84% of patients had hot flashes. Other commonly reported (grade <= 2) reversible toxicities included skin and ocular dryness, fatigue, and mood changes. Serum high-density lipoprotein increased and cholesterol decreased from baseline to month 4. Baseline mean ± SD Cp retinol was 708 ± 280 ng/mL. Mean ± SD Cp of 4-HPR, N-(4-methoxyphenyl) retinamide (4-MPR), and retinol after 1 month of 4-HPR were 0.34 ± 0.21 µmol/L, 0.28 ± 0.21 µmol/L, and 282 ± 127 ng/mL, respectively. Mean retinoid Cps did not change after 3 months of 4-HPR + TAM.

CONCLUSIONS: TAM administration did not affect Cp 4-HPR or 4-MPR. Reversible nyctalopia correlated with relative decrease in Cp retinol but was not symptomatic for most patients. TAM + 4-HPR has acceptable tolerability for this high-risk cohort.


    INTRODUCTION
 TOP
 ABSTRACT
 INTRODUCTION
 PATIENTS AND METHODS
 RESULTS
 DISCUSSION
 REFERENCES
 
TAMOXIFEN (TAM), a nonsteroidal antiestrogen, is associated with a 35% to 50% decreased incidence of contralateral breast cancer when used as adjuvant therapy after initial curative surgery.1 Recently, TAM administration has also been found to decrease the risk of developing breast cancer in women at high risk for this disease.2 The mechanism of action of TAM is presumed to be through its competitive inhibition of estrogen binding to the estrogen receptor (ER). However, it may also perturb tumor growth, or carcinogenesis, through non-ER–mediated pathways.3

Retinoids have also been shown to inhibit tumor growth and induce differentiation in a variety of experimental models. All-trans-retinoic acid (ATRA) has been shown to inhibit growth of ER-positive breast cancer cells, but not ER-negative cancer cell lines.4 Retinoids are presumed to exert their activity via retinoic acid receptors (RARs), although the exact pathways have not been elucidated to date. Transfection of RAR{alpha} into ER-negative cells results in the cells becoming sensitive to the inhibitory effects of ATRA.5 9-cis-retinoic acid, which binds to both RARs and retinoid X receptors, has been shown to downregulate ER RNA and protein.6 These data suggest that there are interactions between retinoid and estrogen-induced signaling and that treatment with a combination of an estrogen antagonist and retinoid may be efficacious in breast cancer.

N-(4-hydroxyphenyl) retinamide ([4-HPR], Fenretinide; R.W. Johnson Pharmaceutical Research Institute, Springhouse, PA) is a semisynthetic retinoid that does not bind well to RAR{alpha}7,8 but may transactivate RAR{gamma}.9 Although the mechanism(s) of action of 4-HPR is not known, the agent has shown activity in both ER-positive and ER-negative breast cancer cells and decreases bcl-2 mRNA levels.8,10,11 4-HPR has also been shown to upregulate the tumor suppressor retinoblastoma protein in ER-positive breast cancer cells.8 4-HPR has been shown to prevent mammary tumors in carcinogen-exposed rats.12 In a study of methylnitrosourea carcinogen-exposed Sprague Dawley rats, the combination of 4-HPR and TAM was superior to either drug alone in the prevention of second primary mammary tumors after excision of the initial tumors.13

In a large Italian trial of 4-HPR in women with surgically treated early-stage breast cancer, the agent was well tolerated. Reversible, symptomatic nyctalopia was observed in approximately 10% of patients.14,15 There was a suggestion that the incidence of nyctalopia is dose-related.14 4-HPR has been shown to lower plasma concentrations of both retinol and retinol-binding protein.16 Decensi et al 17 correlated plasma retinol concentrations (Cp) below 160 ng/mL with moderate alterations in the Goldmann-Weekers dark adaptometry test. The same group described patient age older than 55 years, high percentage of adipose tissue, and higher plasma concentration of the 4-HPR metabolite N-(4-methoxyphenyl) retinamide (4-MPR) as risk factors for severe decrease in retinol Cp.18

In clinical studies, 4-HPR (300 to 400 mg/d) had no activity in a phase II trial in patients with advanced or metastatic breast cancer.19 However, minor responses or disease stabilization was reported in 12 of 15 previously untreated patients with metastatic breast cancer treated in a phase I/II trial with the combination of TAM and 4-HPR.20 These results suggest that the activity of the combination may be greater for early or precancer than for advanced or metastatic disease. Preliminary results from a large randomized trial of 4-HPR versus no intervention in women with surgically treated stage I breast cancer suggested that 4-HPR may be effective in reducing the local recurrence and contralateral breast cancer rates in premenopausal women.21

Although plasma concentrations of 4-HPR and its active metabolite, 4-MPR, have been studied after the administration of 4-HPR as a single agent,18,22 there has been no assessment, to date, of the effect of TAM, if any, on the incidence and severity of clinical toxicity or plasma concentrations of 4-HPR or 4-MPR. However, treatment of mice with phenobarbital, an inducer of cytochrome P450 enzymes, has resulted in lower concentrations of 4-HPR and metabolites in the rodent.23 TAM may also be metabolized, in part, by the cytochrome P450 mixed function oxidase system24-26 and, therefore, may affect plasma concentrations of 4-HPR and its metabolites.

The synergistic effects of TAM and 4-HPR in combination in preventing mammary tumors in preclinical models, the efficacy of TAM in reducing the risk of invasive breast cancer, and the preliminary results suggesting that 4-HPR may be effective in reducing the risk of contralateral breast cancer in premenopausal women, make TAM and 4-HPR an attractive combination for chemoprevention. We performed the first pilot chemoprevention trial of this combination of 4-HPR and TAM in women at high risk for development of invasive breast cancer to assess the tolerability of the combination, document any associated toxicities, test the feasibility of collecting multiple samples longitudinally for assessment of surrogate biomarkers of malignancy, and assess the effect of TAM on steady-state plasma concentrations of 4-HPR and 4-MPR. Because this drug combination was being tested in a healthy population and because toxicity data on long-term administration of TAM + 4-HPR was limited, the trial was designed to administer 4-HPR alone for the initial 25 days, followed by the combination of 4-HPR and TAM for the subsequent 3 months, and then TAM alone for an additional 20 months (2-year total treatment). This design also allowed for assessment of steady-state plasma concentrations of 4-HPR and 4-MPR with and without concurrent TAM. A 200-mg dose of 4-HPR daily was chosen because it had been found to be tolerable in a similar cohort of patients and because it produces serum concentrations of 4-HPR in the range of those found to be effective in vitro. 7,22


    PATIENTS AND METHODS
 TOP
 ABSTRACT
 INTRODUCTION
 PATIENTS AND METHODS
 RESULTS
 DISCUSSION
 REFERENCES
 
Patients
Patients were eligible for the study who were at least 35 years of age and were at high risk of developing invasive breast cancer, defined as (1) a histologically documented diagnosis of ductal carcinoma-in-situ, with or without microinvasion, and treated by standard therapy (lumpectomy and radiation or mastectomy); (2) a histologically documented diagnosis of lobular neoplasia (including atypical lobular hyperplasia or lobular carcinoma-in-situ); (3) atypical ductal hyperplasia in a postmenopausal woman or in a premenopausal woman with a positive family history of breast cancer; or (4) a high-risk family history, defined as breast cancer or ovarian cancer diagnosis in at least three first- or second-degree relatives (at least one of these relatives must have had breast cancer), or at least two first-degree relatives with breast cancer diagnosed under the age of 50 years, or at least one first-degree relative with breast cancer and at least one case of ovarian cancer in the extended pedigree. Patients must have had no concurrent malignancy, cervical carcinoma-in-situ, or any other malignancy within 5 years of study entry. Eligible patients had normal hepatic, renal, and hematopoietic function. All subjects had normal gynecologic examinations before study entry. All subjects were ambulatory, with good performance status (Eastern Cooperative Oncology Group status 0 to 1) and a life expectancy of at least 10 years. All subjects signed an informed consent approved by the Institutional Review Board at the National Cancer Institute. All fertile, sexually active women were informed of possible risks to the fetus and signed a separate consent in which they agreed to use effective, nonhormonal birth control methods for at least 2 months after the end of TAM and at least 12 months after the end of 4-HPR treatment. Patients with a history of bleeding disorder or abnormal coagulation studies, prior history of deep venous thrombosis or pulmonary embolus, abnormal vaginal bleeding, prior retinal disease, macular degeneration or night blindness (nyctalopia), uncontrolled medical or psychiatric illnesses, concurrent hormonal use, or who were pregnant or nursing were excluded from study participation.

Treatment Regimen
4-HPR was supplied by the Cancer Therapy Evaluation Program of the National Cancer Institute (Bethesda, MD), which was responsible for purity and stability. 4-HPR was supplied as 100-mg oil-filled gelatin capsules. 4-HPR 200 mg was administered once daily with the morning meal, which contained the fat equivalent of an 8-ounce glass of whole milk, for 25 days of each 28-day cycle, for four cycles. A 3-day drug holiday was included to allow partial recovery of plasma retinol concentration. TAM 20 mg was obtained from commercial sources and was administered once daily beginning at cycle 2, for a total of 23 cycles.

Pretherapy Evaluation and Follow-Up
Before therapy, all patients had a complete history and physical examination, including pelvic examination. Transvaginal ultrasound of the endometrium was performed in patients who had not had a previous hysterectomy. Patients older than 55 years had a baseline ECG. Blood studies included complete blood cell count, differential count, platelet count, prothrombin time, partial thromboplastin time, luteinizing hormone, follicle stimulating hormone, progesterone, electrolytes, phosphorus, calcium, albumin, total protein, lactate dehydrogenase, uric acid, liver transaminases, total bilirubin, alkaline phosphatase, total and fractionated cholesterol, and triglycerides. A pregnancy test was performed on all women of childbearing potential.

Follow-up evaluations were performed every 2 weeks initially, then every 4 weeks during the 4-HPR treatment, then every 3 to 6 months. Evaluations included blood studies (complete blood cell count, liver function panel, electrolytes, and lipid profile). At 1, 4, and 6 months, and every 6 months to the end of the study, a history, physical examination, and toxicity evaluation were performed. Transvaginal ultrasound with measurement of endometrial thickness was repeated at 4, 12, and 24 months. Mammography and gynecologic examinations were repeated yearly.

Ophthalmologic Toxicity Assessment
Before treatment and after each cycle of 4-HPR treatment, patients were asked specifically about symptoms of nyctalopia (night-blindness). Ophthalmologic examinations were performed at baseline and at any time symptoms of nyctalopia were reported. If no nyctalopia symptoms occurred, examinations were repeated after 1 and 4 months of treatment, between days 18 and 25 of a cycle of 4-HPR. If abnormal, ophthalmologic studies were repeated after 6 months of treatment (at least 2 months after discontinuation of 4-HPR). The complete ophthalmologic examination included manifest refraction, best corrected visual acuity (ETDRS Lighthouse Chart; Lighthouse Low Vision Products, Long Island, NY), slit lamp examination of anterior segment, ophthalmoscopy, and biomicroscopy of the retina. Dark adaptation was measured with a modified Goldmann-Weekers adaptometer. After patients were light-adapted for 5 minutes, the absolute luminance threshold was measured continuously during the dark adaptation until no further threshold changes could be detected in a 10-minute period.27

Tissue Acquisition
Mammographically guided breast biopsies were performed at baseline, 4, and 24 months. All biopsies were performed either with the Mammomat 2 (Siemens, Iselin, NJ) stereotactic biopsy attachment or the Lorad StereoGuide and DSM System (Trex Medical Corporation, Danbury, CT). Most biopsies were performed from the superior aspect, with the breast compressed in the craniocaudal position; some biopsies were performed from the lateral aspect, with the breast in the mediolateral position. All patients underwent 14-gauge core biopsies (22 to 23 mm/core), either with the Magnum gun (Bard, Covington, GA) or the Pro-Mag 2.2 gun (Manan, Northbrook, IL). The biopsy sites were selected based on which areas showed mammographically dense tissue. Five core specimens were obtained under local anesthesia at each time point. Once the site for biopsy had been chosen, a central core specimen was obtained, followed by four more core biopsies 5 mm away in the 3, 6, 9, and 12 o’clock positions to the original core. To spare the patient from five separate skin punctures, we returned to the central position each time an additional core was to be obtained and pulled the skin nick to the next biopsy site before obtaining the specimen. At each follow-up biopsy, we localized the previous biopsy site by looking for a small scar, or comparing the scout views so that the subsequent biopsy was always obtained in the same area of the breast. After the biopsy, the biopsy site was compressed until all bleeding stopped, an ice pack was applied, and the patient was observed for 10 to 15 minutes before discharge. Three core biopsy samples were formalin-fixed, paraffin-embedded, and examined for pathologic abnormalities. Two core biopsies were stored at -70°C for future research studies.

Retinoid Cp
Sample collection. Patients were instructed to take 4-HPR with a morning meal containing the fat equivalent of a glass of whole milk. Patients were further instructed to refrain from taking their study drugs until after blood samples were drawn in a fasting state on the day of pharmacokinetics. Compliance to study drug regimen was assessed by patient interview. Blood samples (7 to 10 mL) were collected in heparinized tubes before treatment and at 1 and 4 months after the start of treatment, between 20 and 24 hours after the last dose of 4-HPR. Additional samples were obtained at 12 months to assess recovery of retinol concentrations. Plasma was separated from whole blood by centrifugation at 2000 x g for 15 minutes at 4°C. All samples were protected from light during collection and separation and were stored at -70°C until analysis.

High-performance liquid chromatography analysis. Retinoid concentrations in plasma were determined by reversed-phase gradient high-performance liquid chromatography with a modification of the method of Bugge et al.28 Briefly, 500 µL of plasma, containing 70 nmol/L Ro-11-5036 (Hoffmann-LaRoche Inc, Nutley, NJ) as internal standard, were extracted with acetonitrile:1-butanol (50:50, vol/vol) in the presence of KH2PO4 (1 kg/L), pH 11.08. The samples were centrifuged and the organic phase was analyzed by high-performance liquid chromatography using a Beckman 506A autosampler (Beckman Instruments, Inc, San Ramon, CA) and a Zorbax ODS special analytic C-18 column with no end-capping (MacMod Analytic, Chadds Ford, PA), 25 cm x 4.6 mm internal diameter, containing five micron spherical particles. Mobile phase A consisted of acetonitrile:0.02 mol/L ammonium acetate:acetic acid (50:50:0.5 by volume), pH 4.6. Mobile phase B consisted of acetonitrile:0.2 mol/L ammonium acetate:acetic acid (95:5:0.4 by volume), pH 8.4. Retinoid peaks were detected at 360 nm with a Beckman model 406 variable wavelength detector. With these conditions, good baseline separation of compounds was achieved, with retention times of approximately 10.6, 12.5, 15.4, 14.8, and 16.5 minutes for internal standard, 4-HPR, retinol, ATRA, and 4-MPR, respectively. No endogenous plasma peaks interfered with the determination of the compounds of interest. Concentrations were determined with reference to a concomitantly performed standard curve. Because the peak absorption wavelength for retinol is 325 nm, determination of retinol concentration required modification of the assay to this wavelength. The assay was linear between 0 and 1 µmol/L 4-HPR and 4-MPR and between 0 and 1000 ng/mL retinol. Intraday and interday coefficient of variation percent was approximately in the range of 5% to 15%. Samples outside the linear range were diluted and assayed again.

Statistical Analysis
The dark adaptation parameters in the same patient were compared before and after 4-HPR and in two different study cycles with paired t tests and Wilcoxon signed rank tests. Linear regression was used to explore the association of rod-cone break time and Cp of retinoids, as previously reported.29

Serum cholesterol, triglyceride, high-density lipoprotein (HDL), and low-density lipoprotein values were compared at baseline, after cycle 1 (4-HPR only), after cycle 4 (4-HPR and TAM), and after 1 year (TAM alone). Changes in HDL level, cholesterol level, and triglyceride level were assessed using the Wilcoxon signed rank test. The distribution of triglyceride levels was highly skewed, and these levels were logarithmically transformed before being tested.


    RESULTS
 TOP
 ABSTRACT
 INTRODUCTION
 PATIENTS AND METHODS
 RESULTS
 DISCUSSION
 REFERENCES
 
Patients and Treatment
Thirty-two women entered onto the trial. Patient characteristics are listed in Table 1. All patients were treated between August 1994 and June 1998. A total of 555 cycles (months) of therapy were administered: 32 cycles of 4-HPR alone, 85 cycles of 4-HPR in combination with TAM, and 438 cycles of TAM alone. The median age of the patients was 49 years (range, 37 to 74 years). Fifty-nine percent of the patients were postmenopausal. Most entered the study with known proliferative breast disease on biopsy. Seventeen patients completed 24 months of treatment, and nine patients continue on study. Six patients did not complete all treatment. Twenty-eight of 32 patients completed at least 4 months of therapy.


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Table 1. Patient Characteristics
 
Toxicity
Toxicities of the treatment were generally mild (Table 2). Six patients did not complete the treatment regimen. Four women discontinued participation because of side effects: one for grade 1 nausea; one for a grade 2 skin rash; one for hot flashes, weight gain, and nausea; and one for atypical migraines, manifesting as temporary loss of vision. Two additional patients discontinued trial participation for reasons unrelated to drug toxicity. One patient developed ductal carcinoma-in-situ, and one patient had exacerbation of pre-existing multiple sclerosis (optic neuritis).


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Table 2. Toxicities
 
The most prominent toxicities encountered were hot flashes in 84% of patients and ophthalmologic symptoms in 21 patients (dry eyes in 17 patients). Mild skin dryness, fatigue, and mood changes were also commonly reported by patients. Seven patients required therapy with antidepressants during the course of the study. Several symptoms were first observed during the month that 4-HPR was administered alone: abdominal pain (four of six patients); nausea (five of eight patients); arthralgia/myalgia (three of five patients); and vomiting (two of two patients). In the majority of cases, these symptoms resolved either before or with cessation of 4-HPR. In contrast, mood alterations were first reported after TAM was begun, either during administration with 4-HPR (eight patients), or during TAM therapy alone (nine patients). Vaginal symptoms were also first reported after TAM was begun, either during administration with 4-HPR (five patients) or during TAM therapy alone (nine patients). Fatigue was first reported with 4-HPR alone in two patients, during TAM in combination with 4-HPR in 12 patients, or during TAM therapy alone in three patients. There were no significant liver function abnormalities. One patient was diagnosed with Crohn’s disease, and one patient was diagnosed with giant cell arteritis while on study. These conditions were not thought to be related to study drug.

Two patients (6%) had symptomatic nyctalopia. Two other patients had transient symptoms that may have been related to impaired dark adaptation. Rod-cone break delay above the upper limits of normal (6.92 minutes) was observed in 16 of 22 patients tested. The two patients with sustained symptomatic nyctalopia had delays of 8.21 and 13.04 minutes.29 All patient visions and rod-cone break delays returned to baseline after 4-HPR was discontinued, even though TAM treatment continued. Four patients were noted to have cataracts; one of these patients had cataract surgery while on study.

Summary data for HDL, cholesterol, and triglycerides are presented in Table 3. Comparisons were made between baseline and the end of cycle 1 (4-HPR alone), between baseline and cycle 4 (combined therapy), and between baseline and year 1. Two significant changes were observed. An increase of serum HDL was noted by cycle 4, but not, interestingly, at year 1, implying that 4-HPR in combination with TAM may have a salutary effect on this cardiovascular risk factor. Also, a decrease in total cholesterol from baseline to month 4 was observed. This decrease was also apparent at year 1. This is consistent with other reports demonstrating a cholesterol-lowering effect of TAM.


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Table 3. Summary Data for Serum Lipid Evaluation
 
Cp Retinol and Pharmacodynamic Assessment
Retinoid Cps at baseline, after 1 and 4 months of 4-HPR treatment, and after 12 months on study are listed in Table 4. Baseline Cp retinol ranged from 296 to 1,433 ng/mL, with a mean ± SD of 708 ± 280 ng/mL. The observed decline in retinol concentrations is relatively stable after 1 month of 4-HPR treatment and recovered to baseline by 12 months on study (8 months after the end of 4-HPR administration). Mean decrease in plasma retinol concentration from baseline to month 4 was 60% (range, 21% to 80%).


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Table 4. Steady-State (Cps) of 4-HPR, 4-MPR, and Retinol
 
There was considerable interpatient variability in the Cp 4-HPR and 4-MPR. For example, for month 4, Cp 4-HPR ranged from 0.15 to 1.11 µmol/L, and Cp 4-MPR ranged from 0.15 to 0.7 µmol/L. The mean concentrations of 4-HPR and 4-MPR were similar after 1 month of 4-HPR alone and after 3 months of 4-HPR + TAM (Table 4). There were four patients who seemed to have a large increase in Cp 4-HPR after the addition of TAM. The largest increase was in patient no. 8, who had a 4-HPR Cp of 0.21 µmol/L after 1 month of 4-HPR alone but a 4-HPR Cp of 1.11 µmol/L after 3 months of the combination. The largest decrease in Cp 4-HPR was in patient no. 12, who had a 4-HPR Cp of 1 µmol/L after 1 month of 4-HPR alone and a Cp 4-HPR of 0.05 µmol/L after 3 months of the combination. There was a significant correlation between the relative decrease in Cp retinol and rod-cone break delay, which has been previously reported.29

Tissue Acquisition
Seventy-eight samples (core needle biopsies) were obtained from 32 patients. Sixty-nine samples (88%) contained adequate tissue for both diagnosis and special studies from at least one of three 14-gauge core needle samples. In 26 patients (81%), adequate tissue as defined by those biopsies that showed acini or ductal epithelium was obtained both before and after treatment with TAM and 4-HPR. In three of these 26 patients, a clinically indicated biopsy (Tru-Cut, reduction mammoplasty) was available and was considered as one of the time points. Two patients discontinued therapy before the posttreatment sample was obtained. Paired samples were inadequate for analysis in four patients; two patients did not have adequate pretreatment tissue, one patient did not have adequate posttreatment tissue, and one patient had inadequate tissue at both time points.

Tissue samples obtained were examined for pathologic diagnosis. One patient was diagnosed with ductal carcinoma-in-situ after a mammographically guided biopsy of an area of changing calcifications observed after 9 months on study. The remaining biopsies were benign, with only one patient demonstrating atypical ductal hyperplasia on a core biopsy obtained for research purposes


    DISCUSSION
 TOP
 ABSTRACT
 INTRODUCTION
 PATIENTS AND METHODS
 RESULTS
 DISCUSSION
 REFERENCES
 
TAM and 4-HPR are an attractive combination for the chemoprevention of breast cancer. 4-HPR and TAM was administered in combination with acceptable toxicity to this high-risk population. Six percent of our patients had symptomatic reversible nyctalopia, which is a similar incidence to that reported by others.16,17,19-22,30 The high incidence of hot flashes in our trial is consistent with that found in the trial of TAM alone in women at high risk of breast cancer reported by the National Surgical Adjuvant Breast and Bowel Project (NSABP).2 In that trial, 82% of 6,466 patients experienced some degree of hot flashes, whereas 84% (27 of 32) of patients in our trial reported hot flashes (Table 2). Other trials using TAM as a chemopreventive reported hot flashes in up to 33% of patients.31-33 Other toxicities were reversible and mostly low-grade, although approximately 20% of women dropped out of the trial even with low-grade toxicities. This drop-out rate is similar to the drop-out rate reported by the NSABP in their prevention trial.2 In that study, 21.6% of patients discontinued assigned therapy for reasons not specified in the protocol, 19.7% of the placebo group, and 23.7% of the TAM group. The toxicities observed in our study with the combination are similar to that reported with TAM and 4-HPR as single agents. Gastrointestinal side effects were first reported most frequently with 4-HPR therapy alone and resolved either before or with the cessation of 4-HPR. Hot flashes, vaginal discharge, menstrual changes, or mood alterations first occurred with TAM administration either in combination with 4-HPR or after TAM discontinuation. In the NSABP prevention study,2 hot flashes and vaginal discharge were noted to be more frequent in the TAM-treated group than in the placebo group. There was no difference noted between the TAM and the placebo group using a self-administered depression scale developed by the Center for Epidemiologic Studies. However, depression was not uncommon, with approximately 35% of patients scoring above 15 in that scale and 9% of patients scoring above 30.

Interestingly, the combination of 4-HPR and TAM was associated with a lowering of serum cholesterol and an increase in serum HDL levels. The effects on HDL did not persist during the treatment with TAM alone. Other studies have reported favorable effects on total cholesterol and low-density lipoprotein cholesterol with TAM treatment. However, in the majority of these studies, HDL levels were either unchanged or slightly reduced.34-38 There was no effect of 4-HPR treatment or the combination treatment of 4-HPR and TAM on serum triglyceride levels, in contrast to hypertriglyceridemia observed with the administration of other retinoids.39 If sustained over longer periods of administration, the cholesterol lowering and HDL increase noted in patients treated with the combination of 4-HPR and TAM, if validated, may lower risk for coronary artery disease.

Our data on the decrease in Cp retinol and its stability after 1 month of 4-HPR therapy are consistent with those reported by Formelli et al, 22 who studied patients receiving 4-HPR alone for 5 years. Taken together, these findings and the clinical findings imply that TAM does not significantly alter the pharmacodynamic effects or the retinol-lowering effect of 4-HPR, at least in the short term.

Our trial design allowed measurement of 4-HPR, 4-MPR, and retinol after 1 month of 4-HPR alone, as well as after 3 months of 4-HPR administered with TAM. The mean concentrations of retinoids did not change with the addition of TAM, indicating no interaction in drug elimination. A minority of our patients had a large increase in both 4-HPR and 4-MPR Cps during the 3 months of treatment with 4-HPR and TAM compared with 4-HPR and 4-MPR Cps after 1 month of 4-HPR treatment alone. This variation could be caused by individual variation in elimination for 4-HPR, variation in the absorption of 4-HPR, or variations in the time of last medication. The fat content of meals can affect the amount of 4-HPR absorbed,40 and variation in the fat content of the diet may account for some of the variability observed. An effect of TAM on 4-HPR absorption (increase) or elimination (decrease) cannot be ruled out for those patients, but individual variation of this magnitude is not unusual and is supported by the wide range 4-HPR concentrations during month 1 (Cp 4-HPR range, 0.1 to 1 µmol/L) and month 4 (Cp 4-HPR range, 0.1 to 1.1 µmol/L; Cp 4-MPR range, 0.1 to 0.7 µmol/L). Formelli et al21 reported that 4-HPR and 4-MPR Cps remained stable throughout a 5-year treatment with 4-HPR and that 4-HPR Cps were approximately 1 µmol/L at a mean of 14 hours (range, 12 to 19 hours) after the last dose. Our data show lower trough concentrations of 4-HPR and 4-MPR, which could reflect differences between the two trials in sampling time relative to drug ingestion (in our trial, samples were obtained approximately 24 hours after dosing) and/or relative to the timing and fat content of food intake.

Relative decreases in Cp retinol from baseline were correlated with changes in dark adaptation. We found no correlation between Cps of 4-MPR and abnormalities in dark adaptation or between abnormal rod-cone break delay and Cp retinol <= 160 ng/mL, as has been reported,15 but the number of patients who had symptomatic nyctalopia in our study was small. Nadir Cp retinol of the two symptomatic patients in our trial were 136 and 336 ng/mL. It is likely that there are individual differences in the concentration of retinol or the ratio of retinol to other compounds, such as ATRA or retinal, which will result in symptomatic nyctalopia. Our study did document, however, that the majority of patients had asymptomatic abnormal dark adaptation while on treatment. These changes were reversible, and the long-term effect of such asymptomatic abnormalities in dark adaptation remains unknown. Because the likelihood of developing an abnormal dark adaptation time was correlated with the ratio of Cp retinol on 4-HPR to baseline retinol concentration, the relative decrease may be more important than the absolute nadir retinol concentration for this toxicity. Whether prolonged exposure to low Cps of 4-HPR, with longer "holidays" for recovery of Cp retinol, is more effective remains to be determined.

Currently, the only definitive chemoprevention trial end point is the incidence of cancer. However, it is not feasible to take every potential chemopreventive agent into large, randomized clinical trials. Therefore, rational clinical evaluation of potential chemoprevention agents will require the identification and validation of relevant surrogate end point biomarkers. A necessary step in this process is to evaluate the feasibility of obtaining adequate tissue for these biomarker studies from a healthy population. In this study, we were able to demonstrate that tissue collection over 2 years was feasible, with adequate tissue for analysis obtained for the majority of patients.

A review of models for early chemoprevention trials in breast cancer and a discussion of potential surrogate molecular markers has recently been published.41 Some potential candidates include the modulation of growth factors and their receptors (transforming growth factor beta, insulin-like growth factor-1, epidermal growth factor receptor modulation of the receptors for selective ER modulators or retinoids [level of expression of ER, progesterone receptor, or the RARs], markers of proliferation [Ki67 and proliferating cell nuclear antigen], and markers of genetic instability [loss of heterozygosity and p53 mutation]). Although we were able to obtain breast tissue for these studies, the amount of breast tissue obtained in a core needle biopsy is limited. Therefore, we are testing candidate markers for modulation after chemopreventive treatment in mammary tissues obtained from studies using methylnitrosourea carcinogen-exposed Sprague Dawley rats before testing these markers on human tissues. We are currently studying the modulation of transforming growth factor beta, a negative growth regulator42 that has been shown to be upregulated after TAM43 and retinoids,44 in this system.

In conclusion, short-term (3 months) administration of TAM and 4-HPR is tolerable in this cohort of patients. Toxicity was mild, and frequent toxicities included mucocutaneous and ocular dryness, hot flashes, and mood changes. Our data suggest a salutary effect of 4-HPR administration on serum cholesterol and HDL levels, which should be confirmed. There was no adverse effect on serum triglyceride levels. There was no evidence that TAM affected 4-HPR pharmacokinetics or that either drug affected toxicity of the other. The effect of longer term administration of 4-HPR + TAM on dark adaptation, development of symptomatic nyctalopia, persistence of hot flashes, retinol Cps, or other toxicities remains unknown. However, given the encouraging preclinical data, toxicity of 4-HPR + TAM administered for longer periods should be assessed.


    ACKNOWLEDGMENTS
 
We thank the following persons for their help in completing this trial: Caroline Barnes; Steven Lemon, MD; Andrea Abati, MD; Richard Lopchinsky, MD; Craig Shriver, MD; Ken Miller, MD; and Michele Gossard.


    REFERENCES
 TOP
 ABSTRACT
 INTRODUCTION
 PATIENTS AND METHODS
 RESULTS
 DISCUSSION
 REFERENCES
 
1. Nayfield SG, Karp JE, Lord LG, et al: Potential role of tamoxifen in prevention of breast cancer. J Natl Cancer Inst 83:1450-1459, 1991[Abstract/Free Full Text]

2. Fisher B, Costantino JP, Wickerham L, et al: Tamoxifen for prevention of breast cancer: Report of the National Surgical Adjuvant Breast and Bowel Project P1 study. J Natl Cancer Inst 90:1371-1388, 1998[Abstract/Free Full Text]

3. Knabbe C, Lippman ME, Wakefield LM, et al: Evidence that transforming growth factor beta is a hormonally-regulated negative growth factor in human breast cancer. Cell 48:417-428, 1986

4. Fontana JA: Interaction of retinoids and tamoxifen on inhibition of human mammary carcinoma cell proliferation. Exp Cell Biol 55:136-144, 1987[Medline]

5. Sheikh MS, Shao ZM, Li XS, et al: Retinoid-resistant estrogen receptor-negative human breast carcinoma cells transfected with retinoic acid receptor alpha acquire sensitivity to growth inhibition by retinoids. J Biol Chem 269:21440-21447, 1994[Abstract/Free Full Text]

6. Rubin M, Fenig E, Rosenauer A, et al: 9-cis retinoic inhibits growth of breast cancer cells and down-regulates estrogen receptor RNA and protein. Cancer Res 54:6549-6556, 1994[Abstract/Free Full Text]

7. Sheikh MS, Shao ZM, Li XS, et al: N-(4-hyroxyphenyl) retinamide (4-HPR)-mediated biological actions involve retinoid receptor-independent pathways in human carcinoma. Carcinogenesis 16:2477-2486, 1995[Abstract/Free Full Text]

8. Kamzi SMI, Plante RK, Visconti V, et al: Comparison of N-(4-hydroxyphenyl) retinamide and all-trans retinoic acid in regulation of retinoid receptor-mediated gene expression in human breast cancer cell lines. Cancer Res 56:1056-1062, 1996[Abstract/Free Full Text]

9. Fanjul AN, Delia D, Pierotti MA, et al: 4-(hydroxyphenyl) retinamide is a highly selective activator of retinoid receptors. Biol Chem 27:22441-22446, 1996

10. Wang TTY, Phang JM: Effect of N-(4-hydroxyphenyl) retinamide on apoptosis in human breast cancer cells. Cancer Res 107:65-71, 1996

11. Coradini D, Biffi A, Pellizzaro E, et al: Combined effect of tamoxifen or interferon-beta and 4-hydroxyphenylretinamide on the growth of breast cancer cell lines. Tumor Biol 18:22-29, 1997

12. Moon RC, Thompson HJ, Becci PJ, et al: N-4-(hydroxyphenyl) retinamide, a new retinoid for the prevention of breast cancer in the rat. Cancer Res 39:1339-1346, 1979[Abstract/Free Full Text]

13. Ratko TA, Detrisac CJ, Dinger NM, et al: Chemopreventive efficacy of combined retinoid and tamoxifen treatment following surgical excision of primary mammary cancer in female rats. Cancer Res 49:4472-4486, 1989[Abstract/Free Full Text]

14. Rotmensz N, DePalo G, Formelli F, et al: Long-term tolerability of Fenretinide (4-HPR) in breast cancer patients. Eur J Cancer 27:1127-1131, 1991

15. Decensi A, Fontana V, Fioretto M, et al: Long-term effects of Fenretinide on retinal function. Eur J Cancer 33:80-84, 1997

16. Peng YM, Dalton WS, Alberts DS, et al: Pharmacokinetics of N-4-hydroxyphenyl retinamide and the effect of its oral administration on plasma retinol concentrations in cancer patients. Int J Cancer 43:22-26, 1989[Medline]

17. Decensi A, Torrisi R, Polizzi A, et al: Effect of the synthetic retinoid Fenretinide on dark adaptation and the ocular surface. J Natl Cancer Inst 86:105-110, 1994[Abstract/Free Full Text]

18. Torrisi R, Parodi S, Fontana V, et al: Factors affecting plasma retinol decline during long term administration of the synthetic retinoid, Fenretinide, in breast cancer patients. Biomarkers Prev 3:507-510, 1994

19. Modiano MR, Dalton WS, Lippman SM, et al: Phase II study of Fenretinide (N-[4-hydroxyphenyl]retinamide) in advanced breast cancer and melanoma. Invest New Drugs 8:317-319, 1990[Medline]

20. Cobleigh MA, Dowlatshahi K, Deutsch TA, et al: Phase I-II trial of tamoxifen with or without Fenretinide, an analog of vitamin A, in women with metastatic breast cancer. J Clin Oncol 11:474-477, 1993[Abstract/Free Full Text]

21. De Palo G, Decenci A, Costa A, et al: A randomized trial of Fenretinide for the prevention of contralateral breast cancer. Am Assoc Cancer Res 40:304, 1999 (abstr 2016a)

22. Formelli F, Clerici M, Campa T, et al: Five-year administration of Fenretinide: Pharmacokinetics and effect on plasma retinol concentrations. J Clin Oncol 11:2036-2042, 1993[Abstract/Free Full Text]

23. Hultin TA, McCormick DL, May CM, et al: Effect of pretreatment with the retinoid N-(4-hydroxyphenyl) all-trans retinamide and phenobarbital on the disposition and metabolism of N-(4-hydroxyphenyl)-all-trans retinamide in mice. Drug Metab Disp 16:783-788, 1988[Abstract]

24. Lim CK, Yuan Z-X, Lamb JH, et al: A comparative study of tamoxifen metabolism in female rat, mouse and human liver microsomes. Carcinogenesis 15:589-593, 1994[Abstract/Free Full Text]

25. Ruenitz PC, Bai X: Acidic metabolites of tamoxifen: Aspects of formation and fate in the female rat. Drug Metab Disp 23:993-998, 1995[Abstract]

26. Wiseman H, Lewis DFV: The metabolism of tamoxifen by human cytochromes P450 is rationalized by molecular modelling of the enzyme-substrate interactions: Potential importance to its proposed anti-carcinogenic/carcinogenic actions. Carcinogenesis 17:1357-1360, 1996[Abstract/Free Full Text]

27. Gunkel RD, Bornschein H: Automatic intensity control in testing dark adaptation. Ophthalmol 57:681-686, 1957

28. Bugge CJL, Rodriguez LC, Vane FM: Determination of isotretinoin or etretinate and their major metabolites in human blood by reverse-phase high performance liquid chromatography. J Pharm Biomed 3:269-277, 1985

29. Caruso RC, Zujewski J, Iwata F, et al: Effects of Fenretinide (4-HPR) on dark adaptation. Arch Ophthalmol 116:759-763, 1998[Abstract/Free Full Text]

30. Costa A, Malone W, Perloff M, et al: Tolerability of the synthetic retinoid Fenretinide (HPR). Eur J Cancer 25:805-808, 1989

31. Jordan VC: Tamoxifen: Toxicities and drug resistance during the treatment and prevention of breast cancer. Pharmacol Toxicol 35:195-211, 1995

32. Powles TJ, Hardy JR, Ashley SE, et al: A pilot trial to evaluate the acute toxicity and feasibility of tamoxifen for prevention of breast cancer. Br J Cancer 60:126-131, 1989[Medline]

33. Powles TJ, Tillyer CR, Jones AL, et al: Prevention of breast cancer with tamoxifen: An update on the Royal Marsden Hospital pilot programme. Eur J Cancer 26:680-684, 1990

34. Gylling H, Pyrhonen S, Mantyla E, et al: Tamoxifen and toremifene lower serum cholesterol by inhibition of delta-8-cholesterol conversion to lathosterol in women with breast cancer. J Clin Oncol 13:2900-2905, 1995[Abstract]

35. Saarto T, Blomqvist C, Ehnholm C, et al: Antiatherogenic effects of adjuvant antiestrogens: A randomized trial comparing the effects of tamoxifen and toremifene on plasma lipid levels in postmenopausal women with node-positive breast cancer. Clin Oncol 14:429-433, 1996

36. Love RR, Wiebe DA, Feyzi JM, et al: Effects of tamoxifen on cardiovascular risk factors in postmenopausal women after 5 years of treatment. J Natl Cancer Inst 86:1534-1539, 1994[Abstract/Free Full Text]

37. Love RR, Newcomb PA, Wiebe DA, et al: Effects of tamoxifen therapy on lipid and lipoprotein levels in postmenopausal patients with node-negative breast cancer. J Natl Cancer Inst 82:1327-1332, 1990[Abstract/Free Full Text]

38. Decensi A, Bonanni B, Guerrieri-Gonzaga A, et al: Biologic activity of tamoxifen at low doses in healthy women. J Natl Cancer Inst 90:1461-1467, 1998[Abstract/Free Full Text]

39. Smith MA, Parkinson DR, Cheson BD, et al: Retinoids in cancer therapy. J Clin Oncol 10:839-864, 1992[Abstract/Free Full Text]

40. Doose DR, Minn FL, Stellar S, et al: Effects of meals and meal composition on the bioavailability of Fenretinide. Pharmacol 32:1089-1095, 1992

41. Fabian CJ, Kimler BF, Elledge RM, et al: Models for early chemoprevention trials in breast cancer. Hematol Oncol Clin North Am 12:993-1017, 1998[Medline]

42. Knabbe C, Lippman ME, Wakefield LM, et al: Evidence that transforming growth factor -b is a hormonally regulated negative growth factor in human breast cancer. Cell 48:417-428, 1987[Medline]

43. Butta A, MacLennan K, Flanders KC, et al: Induction of transforming growth factor-beta1 in human breast cancer in vivo following tamoxifen treatment. Cancer Res 52:4261-4264, 1992[Abstract/Free Full Text]

44. Glick AB, McKune BK, Abdulkarem N, et al: Complex regulation by retinoic acid in the vitamin A-deficient rat. Development 111:1081-1086, 1991[Abstract/Free Full Text]

Submitted January 15, 1999; accepted August 13, 1999.


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