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© 2002 American Society for Clinical Oncology Tumor Microvessel Density as a Predictor of Recurrence After Resection of Hepatocellular Carcinoma: A Prospective StudyByFrom the Center for the Study of Liver Disease (CSLD), Departments of Surgery and Pathology, University of Hong Kong Medical Center, Queen Mary Hospital, Hong Kong, China. Address reprint requests to Ronnie Tung-Ping Poon, MD, Department of Surgery, Queen Mary Hospital, 102 Pokfulam Rd, Hong Kong, China; email: poontp{at}hkucc.hku.hk
PURPOSE: This study prospectively evaluated the correlation of tumor microvessel density (MVD) with clinicopathologic features and postoperative recurrence in patients undergoing resection of hepatocellular carcinoma (HCC). PATIENTS AND METHODS: Tumor MVD was assessed in 100 patients with resection of HCC using a computer image analyzer after immunostaining for CD34 (MVD-CD34) and von Willebrand factor (MVD-vWF), respectively. Patients were prospectively followed for recurrence.
RESULTS: Mean tumor MVD-CD34 (236/0.74 mm2) was higher than mean tumor MVD-vWF (87/0.74 mm2) (P < .001). By multiple regression analysis, tumor size was the only pathologic feature significantly related to tumor MVD-CD34. The median MVD-CD34 was 316/0.74 mm2 in HCCs
CONCLUSION: This study shows that a high MVD-CD34 was predictive of early postresection recurrence in patients with HCCs
ANGIOGENESIS IS A prerequisite for tumor growth and metastasis.1,2 Neovascularization provides not only the route for nutrient supply to the tumor but also the conduit for tumor cells to be shed into the circulation.3 New proliferating capillaries have leaky basement membranes, making them more accessible to tumor cells than mature vessels.4 It has been demonstrated that increasing density of newly formed microvessels in growing tumors correlated closely with increasing number of tumor cells shed into the bloodstream.5 In recent years, mounting evidence has suggested that quantitation of intratumor microvessel density (MVD) by immunostaining for endothelial cell markers, such as CD34 and von Willebrand factor (vWF) may be a useful prognostic predictor in cancer patients.6,7 A prognostic influence of MVD independent of conventional pathologic prognosticators has been demonstrated in a variety of cancers, such as breast carcinoma,8-10 gastric carcinoma,11 colorectal carcinoma,12 pancreatic carcinoma,13 testicular germ cell tumor,14 malignant melanoma,15 and even hematologic malignancies.16,17 However, results of studies on the prognostic value of MVD have not been homogeneous, probably because of factors such as methodologic variation, selection bias in using different areas of tumors for study, and a lack of accurate patient follow-up data in retrospective studies.6 It has been emphasized that the prognostic significance of tumor MVD should be evaluated in a prospective manner with a standardized methodology.6,9 Hepatocellular carcinoma (HCC) is one of the most common malignancies worldwide. It is a tumor characterized by a propensity for vascular invasion and a high metastatic potential. However, there are few reports on the clinical significance of angiogenesis in HCC compared with other common human cancers. Early postoperative recurrence in the liver remnant or distant sites as a result of metastasis is a common phenomenon after resection of HCC.18 Given the relationship between tumor MVD and metastasis found in various cancers, it is intuitive to hypothesize that tumor MVD may be predictive of early recurrence after resection of HCC. So far, to our knowledge, only three groups of investigators have evaluated the prognostic value of tumor angiogenesis in HCC.19-22 One Japanese group, using vWF as the endothelial marker, found that high tumor MVD by immunostaining was an adverse prognostic factor for disease-free survival after resection of HCC.19,20 However, another Japanese group observed that anti-CD34 gave more reliable and specific staining for neovessels compared with anti-vWF in HCC and that high MVD by CD34 immunostaining was predictive of worse survival results after resection of HCC.21 More recently, a Chinese group reported that high tumor MVD by CD34 immunostaining was an adverse prognostic factor for disease-free survival in small HCCs less than 5 cm but not in HCCs greater than 5 cm.22 All these studies were retrospective, and their results were inconclusive. Therefore, we conducted a prospective study using a standardized methodology to evaluate the prognostic value of tumor MVD in relation to early recurrence after curative resection of HCC.
Patients and Tissue Samples Over a 20-month period from January 1998 to August 1999, 100 patients with curative resection of HCC, defined as complete macroscopic removal of the tumor, were recruited into a prospective study to evaluate the correlation of tumor MVD by CD34 and vWF immunostaining, respectively, with the clinicopathologic features and postoperative recurrence. The study protocol was approved by the research ethics committee of our institution, and informed consent was obtained from all participants. The average age of the patients was 55.0 ± 12.7 years (mean ± SD; range, 18 to 75 years). There were 77 men and 23 women. The average tumor size was 6.8 ± 4.4 cm (range, 1.5 to 22 cm), with 46 tumors less than 5 cm. Among the 100 patients with HCC in this study, 83 had hepatitis B infection, four had hepatitis C infection, three had alcoholic cirrhosis, and 10 had HCC of unknown etiology. None of the patients received any preoperative treatment for the HCC, such as transarterial chemoembolization and percutaneous ethanol injection therapy. No postoperative adjuvant chemotherapy was given, except for one patient who received postoperative transarterial chemotherapy for positive histologic resection margin. Immediately on resection of the tumors in the operating theatre, tumor specimens were taken from areas next to the margin of the tumors as well as from more central areas; necrotic tissue was avoided. Adjacent nontumorous liver tissue was also collected. The fresh tissue specimens were fixed in 10% buffered formalin and embedded in paraffin. Histologic sections of 4-µm thickness were prepared for immunohistochemical study.
Immunohistochemical Staining for CD34 and vWF
Determination of MVD
Clinicopathologic and Follow-Up Data Detailed histologic examination of all resected specimens was performed by a senior pathologist specializing HCC pathology who was blinded to the MVD results. Tumors were graded according to Edmonson’s criteria.23 Serial sections of the tumors and surrounding liver were examined to identify any tumor encapsulation, microscopic venous invasion, and microsatellite lesions. Follow-up was complete for all patients, who were prospectively monitored for tumor recurrence by serum AFP level monthly and chest x-ray together with CT scan every 3 months. The median follow-up of all patients was 27 months (range, 18 to 38 months). A diagnosis of recurrence was based on typical imaging appearance in CT scan and an elevated AFP level. In uncertain cases, fine-needle aspiration cytology was performed to confirm diagnosis. All clinicopathologic and follow-up data were prospectively entered into a computerized database.
Statistical Analysis
MVD by CD34 and vWF Immunostaining in Tumor and Nontumorous Liver In all tumors collected, the density of microvessels was higher in the peripheral tumor tissue close to the margin than in the central areas. Therefore, the peripheral tissue sections were used for counting of microvessels. Specific staining of capillary-like vessels by anti-CD34 was observed in all tumor specimens (mean MVD-CD34, 236 ± 121/0.74 mm2; median, 236/0.74 mm2; range, 24 to 580/0.74 mm2; Fig 1). In nontumorous liver tissues, which were either cirrhotic or associated with chronic hepatitis, there was no or sparse staining (mean MVD-CD34, 8 ± 5/0.74 mm2; range, 0 to 36/0.74 mm2; Fig 1). The nontumorous liver MVD-CD34 was significantly lower than the tumor MVD-CD34 (P < .001). There was no significant difference in MVD-CD34 between cirrhotic (20 ± 6/0.74 mm2) and noncirrhotic liver (14 ± 4/0.74 mm2) (P = .543).
The pattern of staining by anti-vWF was different from that by anti-CD34, with staining of mainly larger vessels with wider lumen in the fibrous tissue within the tumor, rather than the capillary-like vessels between cancer cells (Fig 2). The MVD-vWF in tumors (mean, 87 ± 62/0.74 mm2; median, 70/0.74 mm2; range, 8 to 194/0.74 mm2) was significantly lower than the MVD-CD34 (P < .001). There was a significant but weak positive correlation between MVD-CD34 and MVD-vWF (r = .280, P = .007). In nontumorous liver tissues, staining by anti-vWF was confined to larger vessels in the portal triad, with no staining in the sinusoids. The nontumorous MVD-vWF (mean, 18 ± 6/0.74 mm2; range, 2 to 52/0.74 mm2) was also significantly lower than the tumor MVD-vWF (P < .001). There was no significant difference in MVD-vWF between cirrhotic (21 ± 7/0.74 mm2) and noncirrhotic liver (15 ± 5/0.74 mm2) (P = .224).
Correlation Between Tumor MVD and Clinicopathologic Features Table 1 compares tumor MVD-CD34 and tumor MVD-vWF between patient subgroups categorized according to various clinicopathologic parameters. Significantly higher MVD-CD34 was associated with a low preoperative serum AFP level (P = .005), tumor size  5 cm (P < .001), absence of venous invasion (P = .011), and absence of microsatellite lesion (P = .017) (Table 1). When these variables were entered into a multiple regression analysis, tumor size was found to be the only significant independent pathologic feature related to MVD-CD34 (P < .001). The influence of other pathologic parameters on MVD by univariate analysis could be attributed to their confounding relationship with tumor size. Figure 3 depicts a scatter plot of tumor MVD-CD34 versus tumor size. There was a significant negative correlation between MVD-CD34 and tumor size (r = -.522, P < .001).
Table 2 shows a comparison of the pathologic features, arterial vascularity on CT scan, and tumor MVD between tumors 5 cm and tumors greater than 5 cm. HCCs 5 cm had a significantly lower frequency of venous invasion and microsatellite lesions and also a lower frequency of arterial hypervascularity compared with large tumors. However, HCCs 5 cm were observed to have a higher MVD-CD34. When further subdividing HCCs 5 cm into tumors 3 cm (n = 20; mean diameter, 1.8 ± 0.54 cm) and tumors of 3.1 to 5 cm (n = 26; mean diameter, 4.0 ± 0.60 cm), there were no significant differences in the frequencies of tumor encapsulation (35% v 54%, P = .092), Edmonson grade III/IV (30% v 38%, P = .550), venous invasion (20% v 19%, P = .617), microsatellite nodules (20% v 23%, P = .537), or arterial hypervascularity on CT scan (55% v 73%, P = .202) between the two subgroups. The tumor MVD-CD34 was not significantly different between tumors 3 cm and tumors 3.1 to 5 cm (320 ± 140 mm2 v 295 ± 94/0.74 mm2, P = .350).
When MVD-vWF was correlated with clinicopathologic features, a significant relationship was observed only with tumor size (Table 1). The mean MVD-vWF was higher in HCCs 5 cm than in HCCs more than 5 cm (P = .042). However, there was no significant correlation between MVD-vWF and tumor size when the two were correlated as continuous variables by linear regression analysis (r = -.087, P = .212). No significant association between MVD-vWF and other pathologic features was noted. The MVD-vWF was comparable between tumors 3 cm and tumors 3.1 to 5 cm (87 ± 76 mm2 v 90 ± 55/0.74 mm2, P = .852).
Prognostic Influence of Tumor MVD on Postoperative Recurrence
Further analyses were performed for patients with tumor size
Using tumor MVD-vWF instead of MVD-CD34 for analysis in patients with HCC 5 cm, a trend toward worse disease-free survival among patients with higher than median MVD-vWF was observed when compared with patients with lower than median MVD-vWF, but the difference was not statistically significant (P = .059, Fig 5). Neither tumor MVD-CD34 nor tumor MVD-vWF was a significant predictive factor for disease-free survival in patients with HCCs greater than 5 cm. By multivariate analysis, the presence of venous invasion was the only factor predictive of disease-free survival in patients with large HCC (risk ratio, 3.41; 95% confidence interval, 1.44 to 8.08, P = .005).
To our knowledge, this is the first prospective study of the prognostic significance of tumor MVD in HCC. Our study differs from previous retrospective studies in three important aspects.19-22 First, we have standardized the tumor sections for MVD assessment to tissue from peripheral areas next to tumor margin in all cases. The use of archival tissue blocks in previous studies is suboptimal as the area of tumor examined might not be standardized, and this may be a factor leading to variation in results. Microvessels have been shown to be heterogeneously distributed inside the tumor.6,9 It has been well documented in other cancers that maximal MVD is observed near the growing edge of the tumor.6,9,10 A comparison of peripheral and central tumor sections in this study indicates that this is also true for HCC. Second, we used a computer image analyzer to minimize the interobserver variation, whereas MVD was assessed by manual count under light microscope in previous studies. In a study of breast cancer, it was demonstrated that MVD obtained with an image analyzer, but not that obtained from a manual count, was an independent prognostic factor, suggesting that the former method is more objective in estimating MVD.10 Third, the prospective documentation of clinicopathologic features and follow-up results ensured optimum accuracy of data. The double-blind design in the enumeration of MVD and histopathologic examination by independent investigators also helped to prevent observer-related bias. A few different endothelial cell markers, including CD31, CD34, vWF, and UEA-1, have been investigated for localization of endothelial cells in HCC.24,25 Several studies have suggested that CD34 may be a more sensitive and specific marker than other endothelial cell markers for microvessels in HCC.21,24-26 In our study, intense staining of capillary-like vessels between HCC cells was observed with CD34 immunohistochemistry, whereas vWF antibody reacted mainly with large vessels in the fibrous tissue. CD34 is preferentially expressed on the surface of regenerating or migrating endothelial cells and is a marker of proliferating endothelial cells in the growing sprouts during angiogenesis.27 Microvessels stained by anti-CD34 are capillary-like, rather than having the appearance of sinusoids in normal liver. A previous study also reported that the vessels of HCC lack the specifically differentiated morphology of normal sinusoids and develop the characteristics of capillary vessels.28 Overall, given our results, CD34 seems to be a more reliable endothelial marker than vWF that correlates with angiogenesis during the progression of HCC.
This study demonstrates a higher MVD in HCCs
While there was a general trend of higher MVD-CD34 in smaller HCC, the scatter plot in Fig 3 shows that there was a considerable variation in the MVD-CD34 even for tumors of similar size, especially among HCCs Most patients in this study had HCC related to hepatitis B viral infection, which is endemic in our population. Recent studies have suggested that angiogenesis may be different in livers infected with hepatitis B or hepatitis C viruses.20,32 It would be of interest to compare MVD of the tumors and the nontumorous livers between patients with hepatitis B–related HCC and those with hepatitis C–related HCC. However, the small number of patients with hepatitis C–related HCC (n = 4) in our study precluded a statistically meaningful comparison of MVD between hepatitis B– and hepatitis C–related HCCs. Further studies in patient populations with a high incidence of both hepatitis B– and hepatitis C–related HCCs are needed to elucidate the differences in angiogenesis of HCCs caused by these two viruses.
In this study, high MVD-CD34 was found to be the only independent predictor of recurrence for patients with HCCs
Our findings suggest that a high MVD may have an important contribution to postoperative recurrence after resection of small HCCs
The findings of the current study may have potential therapeutic and prognostic implications in HCCs. Several antiangiogenic agents that inhibit proliferation of endothelial cells in tumor microvessels have been used in clinical trials.40 Animal studies have demonstrated inhibition of HCC growth and metastasis by antiangiogenic therapy,41,42 and clinical trial of antiangiogenic therapy in HCC patients has been started recently.43 As the main target of antiangiogenic therapy is the inhibition of microvessel formation, the finding of higher MVD in HCCs
The identification of tumor MVD as a new prognostic marker in patients with small HCCs is important because prediction of recurrence by conventional parameters in this group of patients with apparently "early" HCC is difficult. In several types of cancers, tumor MVD has been shown to predict recurrence in patients with apparently early disease by conventional pathologic criteria, such as early-stage breast carcinoma,8 node-negative colon cancer,12 stage A testicular tumor,14 and thin malignant melanoma.15 Apart from its prognostic role in patients undergoing resection of HCC, assessment of tumor MVD may also have a potential value in predicting recurrence after transplantation for HCC. Currently, only patients with HCCs
In conclusion, this first prospective study of the prognostic value of angiogenesis in HCC shows the following: (1) CD34 seems to be a better endothelial marker than vWF for the study of MVD in HCC; (2) tumor angiogenesis as reflected by MVD is more active in HCCs
Supported by a Committee on Research and Conference Grants research grant from the University of Hong Kong, Hong Kong, China. We thank Daniel Fong, PhD, Senior Medical Statistician of the Clinical Trials Center of the University of Hong Kong, for his advice on statistical analysis in the manuscript.
An abstract of this study was presented at the American Association of Cancer Research Conference "Angiogenesis and Cancer: From Basic Mechanisms to Therapeutic Implications" in Traverse City, MI, October 11-15, 2000.
1. Folkman J: What is the evidence that tumors are angiogenesis dependent? J Natl Cancer Inst 82: 4-6, 1990 2. Liotta LA, Steeg PS, Stetler-Stevenson WG: Cancer metastasis and angiogenesis: An imbalance of positive and negative regulation. Cell 64: 327-336, 1991[CrossRef][Medline] 3. Folkman J: Tumor angiogenesis. Adv Cancer Res 43: 175-203, 1985[Medline] 4. Nagy JA, Brown LF, Senger DR, et al: Pathogenesis of tumor stroma generation: A critical role for leaky blood vessels and fibrin deposition. Biochim Biophys Acta 948: 305-326, 1989[Medline]
5.
Liotta L, Kleinerman J, Saidel G: Quantitative relationships of intravascular tumor cells, tumor vessels, and pulmonary metastases following tumor implantation. Cancer Res 34: 997-1004, 1974 6. Weidner N: Intratumor microvessel density as a prognostic factor in cancer. Am J Pathol 147: 9-19, 1995[Medline]
7.
Folkman J: Seminars in medicine of the Beth Israel Hospital, Boston: Clinical applications of research on angiogenesis. N Engl J Med 333: 1757-1763, 1995
8.
Weidner N, Folkman J, Pozza F, et al: Tumor angiogenesis: A new significant and independent prognostic indicator in early-stage breast carcinoma. J Natl Cancer Inst 84: 1875-1887, 1992
9.
Gasparini G, Harris AL: Clinical importance of the determination of tumor angiogenesis in breast carcinoma: Much more than a new prognostic tool. J Clin Oncol 13: 765-782, 1995 10. Acenero MJ, Gonzalez JF, Gallego MG, et al: Vascular enumeration as a significant prognosticator for invasive breast carcinoma. J Clin Oncol 16: 1684-1688, 1998[Abstract]
11.
Maeda K, Chung YS, Takatsuka S, et al: Tumor angiogenesis as a predictor of recurrence in gastric carcinoma. J Clin Oncol 13: 477-481, 1995 12. Frank RE, Saclarides TJ, Leurgans S, et al: Tumor angiogenesis as a predictor of recurrence and survival in patients with node-negative colon cancer. Ann Surg 222: 695-699, 1995[Medline] 13. Niedergethmann M, Hildenbrand R, Wolf G, et al: Angiogenesis and cathepsin expression are prognostic factors in pancreatic adenocarcinoma after curative resection. Int J Pancreatol 28: 31-39, 2000[Medline]
14.
Olivarez D, Ulbright T, DeRiese W, et al: Neovascularization in clinical stage A testicular germ cell tumor: Prediction of metastatic disease. Cancer Res 54: 2800-2802, 1994 15. Graham CH, Rivers J, Kerbel RS, et al: Extent of vascularization as a prognostic indicator in thin (<0.76mm) malignant melanomas. Am J Pathol 145: 510-514, 1994[Abstract] 16. Vacca A, Ribatti D, Ruco L, et al: Angiogenesis extent and macrophage density increase simultaneously with pathological progression in B-cell non-Hodgkin’s lymphomas. Br J Cancer 79: 965-970, 1999[CrossRef][Medline]
17.
Padro T, Ruiz S, Bieker R, et al: Increased angiogenesis in the bone marrow of patients with acute myeloid leukemia. Blood 95: 2637-2644, 2000 18. Poon RTP, Fan ST, Wong J: Risk factors, prevention and management of postoperative recurrence after resection of hepatocellular carcinoma. Ann Surg 232: 10-24, 2000[CrossRef][Medline] 19. El-Assal ON, Yamanoi A, Soda Y, et al: Clinical significance of microvessel density and vascular endothelial growth factor expression in hepatocellular carcinoma and surrounding liver: Possible involvement of vascular endothelial growth factor in the angiogenesis of cirrhotic liver. Hepatology 27: 1554-1562, 1998[CrossRef][Medline] 20. Yamamoto A, Dhar DK, El-Assal ON, et al: Thymidine phosphorylase (platelet-derived endothelial cell growth factor), microvessel density and clinical outcome in hepatocellular carcinoma. J Hepatol 29: 290-299, 1998[CrossRef][Medline] 21. Tanigawa N, Lu C, Mitsui T, et al: Quantitation of sinusoid-like vessels in hepatocellular carcinoma: Its clinical and prognostic significance. Hepatology 26: 1216-1223, 1997[CrossRef][Medline] 22. Sun HC, Tang ZY, Li XM, et al: Microvessel density of hepatocellular carcinoma: Its relationship with prognosis. J Cancer Res Clin Oncol 125: 419-426, 1999[CrossRef][Medline] 23. Edmonson HA, Steiner PE: Primary carcinoma of the liver: A study of 100 among 48,900 necropsies. Cancer 7: 462-503, 1954[CrossRef][Medline]
24.
Anthony PP, Ramani P: Endothelial markers in malignant vascular tumours of the liver: Superiority of QB-END/10 over von Willebrand factor and Ulex europaeus agglutinin 1. J Clin Pathol 44: 29-32, 1991 25. Ruck P, Xiao JC, Kaiserling E: Immunoreactivity of sinusoids in hepatocellular carcinoma: An immunohistochemical study using lectin UEA-1 and antibodies against endothelial markers, including CD34. Arch Pathol Lab Med 119: 173-178, 1995[Medline] 26. Cui S, Hano H, Sakata A, et al: Enhanced CD34 expression of sinusoid-like vascular endothelial cells in hepatocellular carcinoma. Pathol Int 46: 751-756, 1996[Medline] 27. Schlingemann RO, Rietveld FJ, de-Waal RM, et al: Leukocyte antigen CD34 is expressed by a subset of cultured endothelial cells and on endothelial abluminal microprocesses in the tumor stroma. Lab Invest 62: 690-696, 1990[Medline] 28. Haratake J, Scheuer PJ: An immunohistochemical and ultrastructural study of the sinusoids of hepatocellular carcinoma. Cancer 65: 1985-1993, 1990[CrossRef][Medline] 29. Ebara M, Ohto M, Shinagawa T, et al: Natural history of minute hepatocellular carcinoma smaller than three centimeters complicating cirrhosis: A study in 22 patients. Gastroenterology 90: 289-298, 1986[Medline] 30. Okazaki N, Yoshino M, Yoshida T, et al: Evaluation of the prognosis for small hepatocellular carcinoma based on tumor volume doubling time: A preliminary report. Cancer 63: 2207-2210, 1989[CrossRef][Medline] 31. Terada T, Nakanuma Y: Arterial elements and perisinusoidal cells in borderline hepatocellular nodules and small hepatocellular carcinomas. Histopathology 27: 333-339, 1995[Medline] 32. Mazzanti R, Messerini L, Monsacchi L, et al: Chronic viral hepatitis induced by hepatitis C but not hepatitis B virus infection correlates with increased liver angiogenesis. Hepatology 25: 229-234, 1997[CrossRef][Medline] 33. Nagao T, Inoue S, Yoshimi F, et al: Postoperative recurrence of hepatocellular carcinoma. Ann Surg 211: 28-33, 1990[Medline] 34. Jwo SC, Chiu KH, Chau GY, et al: Risk factors linked to tumor recurrence of human hepatocellular carcinoma after hepatic resection. Hepatology 16: 1367-1371, 1992[Medline] 35. Lai CS, Ng IOL, You KT, et al: Hepatic resection for small hepatocellular carcinoma: The Queen Mary Hospital experience. World J Surg 15: 654-659, 1991[CrossRef][Medline] 36. Shirabe K, Kanematsu T, Matsumata T, et al: Factors linked to early recurrence of small hepatocellular carcinoma after hepatectomy: Univariate and multivariate analysis. Hepatology 14: 802-805, 1991[Medline] 37. Maeda T, Takenaka K, Taguchi K, et al: Clinicopathological characteristics of surgically resected minute hepatocellular carcinomas. Hepatogastroenterology 47: 498-503, 2000[Medline] 38. Tang Z, Qin L, Wang X, et al: Alterations of oncogenes, tumor suppressor genes and growth factors in hepatocellular carcinoma: With relation to tumor size and invasiveness. Chin Med J (Engl) 111: 313-318, 1998[Medline] 39. Poon RTP, Fan ST, Ng IOL, et al: Different risk factors and prognosis for early and late intrahepatic recurrence after resection of hepatocellular carcinoma. Cancer 89: 500-507, 2000[CrossRef][Medline] 40. Thompson WD, Li WW, Maragoudakis M: The clinical manipulation of angiogenesis: Pathology, side-effects, surprises and opportunities with novel human therapies. J Pathol 190: 330-337, 2000[CrossRef][Medline] 41. Xia JL, Yang BH, Tang ZY, et al: Inhibitory effect of the angiogenesis inhibitor TNP-470 on tumor growth and metastasis in nude mice bearing human hepatocellular carcinoma. J Cancer Res Clin Oncol 123: 383-387, 1997[Medline] 42. Kin M, Torimura T, Ueno T, et al: Angiogenesis inhibitor TNP-470 suppresses the progression of experimentally-induced hepatocellular carcinoma in rats. Int J Oncol 16: 375-382, 2000[Medline] 43. Patt YZ, Hassan MM, Lozano RD, et al: Durable clinical response of refractory hepatocellular carcinoma to orally administered thalidomide. Am J Clin Oncol 23: 319-321, 2000[Medline] 44. Lau WY, Leung TW, Ho SK, et al: Adjuvant intra-arterial iodine-131-labelled lipiodol for resectable hepatocellular carcinoma: A prospective randomised trial. Lancet 353: 797-801, 1999[CrossRef][Medline] 45. Takayama T, Sekine T, Makuuchi M, et al: Adoptive immunotherapy to lower postsurgical recurrence rates of hepatocellular carcinoma: A randomised trial. Lancet 356: 802-807, 2000[CrossRef][Medline] 46. Ikeda K, Arase Y, Saitoh S, et al: Interferon beta prevents recurrence of hepatocellular carcinoma after complete resection or ablation of the primary tumor: A prospective randomized study of hepatitis C virus-related liver cancer. Hepatology 32: 228-232, 2000[CrossRef][Medline] 47. Wang L, Tang ZY, Qin LX, et al: High-dose and long-term therapy with interferon-alpha inhibits tumor growth and recurrence in nude mice bearing human hepatocellular carcinoma xenografts with high metastatic potential. Hepatology 32: 43-48, 2000[CrossRef][Medline]
48.
Mor E, Kaspa RT, Sheiner P, et al: Treatment of hepatocellular carcinoma associated with cirrhosis in the era of liver transplantation. Ann Intern Med 129: 643-653, 1998 49. Bismuth H, Majno PE, Adam R: Liver transplantation for hepatocellular carcinoma. Semin Liver Dis 19: 311-322, 1999[Medline]
50.
Schlitt HJ, Neipp M, Weimann A, et al: Recurrence patterns of hepatocellular and fibrolamellar carcinoma after liver transplantation. J Clin Oncol 17: 324-331, 1999 Submitted June 26, 2001; accepted December 17, 2001.
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Copyright © 2002 by the American Society of Clinical Oncology, Online ISSN: 1527-7755. Print ISSN: 0732-183X
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ABSTRACT
INTRODUCTION
2 test with Yates’ correction for categorical variables. Correlation between continuous variables was performed with linear regression analysis. Confounding pathologic variables were entered into a multiple regression analysis to evaluate any independent relationship between each pathologic variable and MVD. Disease-free survival rates were computed by the Kaplan-Meier method and were compared by the log-rank test. Multivariate analysis of the influence of MVD and other clinicopathologic factors on disease-free survival was made by the Cox proportional hazards model. In the evaluation of the prognostic influence of MVD-CD34 and MVD-vWF in the whole cohort or in subgroups of patients stratified by tumor size less than or equal to or more than 5 cm, the median value in each group was used as the cutoff value for comparison.
