|
Advertisement |
|
|
||
 |
|
|||||
|
|||||
|
 |
||||||
|
||||||
|
||||||
|
Journal of Clinical Oncology, Vol 24, No 12 (April 20), 2006: pp. 1963-a-1964 © 2006 American Society of Clinical Oncology. DOI: 10.1200/JCO.2006.05.8883
In Reply:Chao Family Comprehensive Cancer Center, Division of Hematology/Oncology, Genetic Epidemiology Research Institute, and Division of Epidemiology, Department of Medicine, School of Medicine, University of California Irvine, Irvine CA
Division of Hematology/Oncology, Genetic Epidemiology Research Institute, and Division of Epidemiology, Department of Medicine, School of Medicine, University of California Irvine, Irvine CA Our epidemiologic analysis, as reported in Journal of Clinical Oncology1 on the survival for bronchioloalveolar carcinoma (BAC) patients diagnosed during the period 1995-2003 clearly demonstrates improved survival for BAC patients diagnosed after May 1999. This date coincides with release of the revised 1999 WHO classification of lung tumors.2 The observed survival benefit persisted after adjustment for sex, stage at presentation, and smoking status. In their letter to the editor, Tsurutani et al have proposed that the influence of the 1999 WHO classification of lung tumors on survival for BAC patients has been overstated. Rather, they suggest that the improvement for BAC patients after May1999 is likely due to factors unaccounted for by our population-based analysis (ie, advances in radiographic imaging techniques, and new salvage chemotherapeutic and biologic regimens). An important aspect of our study, as published in Figure 3 of the original article,1 is that survival was improved for BAC patients (n = 626) but not for nonBAC non–small-cell lung cancer (NSCLC) patients (n = 11,343) during the exact same time periods. Any improvements in the diagnosis or treatment of NSCLC during these time periods likely would be reflected among nonBAC NSCLC patients (ie, 95% of the NSCLC population). While we are aware of the significant advances in lung cancer management over the past decade, no analytic data exist to support the claim that improved radiographic and therapeutic techniques developed between May 1999 and December 2003 affect survival of BAC patients preferentially over nonBAC NSCLC patients. Furthermore, as noted in the original article, the first epidermal growth factor receptor tyrosine kinase inhibitor was not approved by the United States Food and Drug Administration for use until 2003, in the last 8 months of the 9-year period analyzed in our study.3 Our original hypothesis did not assume that immediately effective June first 1999, all community pathologists complied with the revised 1999 WHO classification of lung tumors. In fact, these criteria were presented at major international conferences before and after the original release date of the 1999 WHO definition, including the XXII International Congress of Pathology in Nice, France, on October 22, 1998, and on September 11, 2000, at the 9th World Conference on Lung Cancer in Tokyo, Japan (W. Travis, personal communication, April 2005). We hypothesized that over time, with increasing awareness and compliance by community pathologists to the 1999 WHO criteria, survival for BAC patients would be affected. The accuracy of lung cancer histologic classification using Surveillance, Epidemiology, and End Results data from a statewide cancer registry has been evaluated compared with independent histologic review, with favorable results.4 In an accompanying editorial by Henson and Albores-Saavedra5 on the above Surveillance, Epidemiology, and End Results analysis, it has been noted that although diagnostic variation exists among community pathologists in population-based cancer registries, the large sample size in population-based studies results in regression toward the mean for histologic tumor types. We do not believe that the influence of the 1999 WHO classification on survival for BAC patients has been overstated. In fact, the original surgical series by Noguchi et al6 (which contributed to the revisions made in the 1999 WHO classification of lung tumors) demonstrated a 100% 5-year survival for BAC patients with solitary, noninvasive tumors < 2.0 cm. In our published lung cancer-specific survival analyses adjusted for equal follow-up duration, during January 1995 to May 1999, 37 deaths caused by lung cancer occurred out of 138 local stage BAC patients, whereas during June 1999 to December 2003, only five deaths occurred out of 150 local stage BAC patients.1 Though lung cancer-specific survival has improved (ie, regressed to a new mean) after May 1999, the cure rate does not yet reach 100% as noted in the aforementioned surgical series. We recognize that population-based analyses are limited compared with clinical trials in the availability of independent histologic review, and information on second-line chemotherapeutic regimens or new radiographic staging techniques. However, a great strength of such analysis is the ability to observe survival trends for all affected patients (regardless of treatment or comorbidities) within a given geographic region over prolonged time periods. We encourage the continued pursuit of monitoring cancer outcomes via epidemiologic analyses, to detect emerging trends and update our knowledge-base on specific cancers in this time of rapidly advancing technologies and therapeutic developments. Authors' Disclosures of Potential Conflicts of Interest The authors indicated no potential conflicts of interest. REFERENCES
1. Zell JA, Ou SHI, Ziogas A, et al: Epidemiology of bronchioloalveolar carcinoma: Improvement in survival after release of the 1999 WHO classification of lung tumors. J Clin Oncol 23:8396-8405, 2005 2. Travis WD, Colby TV, Corrin B, et al: World Health Organization International Histological Classification of Tumours: Histological Typing of Lung and Plueral Tumours (ed 3). Berlin, Germany, Springer, 1999 3. Cohen MH, Williams GA, Sridhara R, et al: United States Food and Drug Administration drug approval summary: Gefitinib (ZD1839; Iressa) tablets. Clin Cancer Res 10:1212-1218, 2004 4. Field RW, Smith BJ, Platz CE, et al: Lung cancer histologic type in the surveillance, epidemiology, and end results registry versus independent review. J Natl Cancer Inst 96:1105-1107, 2004 5. Henson DE, Albores-Saavedra J: Checking up on the Surveillance, Epidemiology, and End Results program. J Natl Cancer Inst 96:1050-1051, 2004 6. Noguchi M, Morikawa A, Kawasaki M, et al: Small adenocarcinoma of the lung: Histologic characteristics and prognosis. Cancer 75:2844-2852, 1995[CrossRef][Medline] Related Correspondence
|
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|
|
|||||||||||
|
|||||||||||
|
|
Copyright © 2006 by the American Society of Clinical Oncology, Online ISSN: 1527-7755. Print ISSN: 0732-183X
|
