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Surgical Removal of the Primary Tumor Increases Overall Survival in Patients With Metastatic Breast Cancer: Analysis of the 1988-2003 SEER Data
Surgical Removal of the Primary Tumor Increases Overall Survival in Patients With Metastatic Breast Cancer: Analysis of the 1988-2003 SEER Data Gnerlich J, Jeffe DB, Deshpande AD, et al (Washington Univ School of Medicine, St Louis, Mo; Saint Louis Univ School of Public Health, Mo) Ann Surg Oncol 14:2187-2194, 2007
Background.—Primary treatments for stage IV breast cancer are chemotherapy and radiation, with surgery usually reserved for tumor-related complications. We sought to determine whether surgical removal of the primary tumor provides a survival advantage for women with metastatic breast cancer. Methods.—We conducted a retrospective, population-based cohort study by using the 1988–2003 Surveillance, Epidemiology, and End Results (SEER) program data. By use of multivariate Cox regression models, overall survival in women with stage IV disease was compared between women who underwent surgical excision of their breast tumor with women who did not, controlling for potential confounding demographic, tumor- and treatment-related variables, and propensity scores (accounting for variables associated with the likelihood of having surgery). Results.—Of 9734 SEER patients with stage IV breast cancer, 47% under-
went breast cancer surgery and 53% did not. Median survival was longer for women who had surgery than for women who did not, both among women who were alive at the end of the study period (36.00 vs. 21.00 months; P < .001) and among women who had died during follow-up (18.00 vs. 7.00 months; P < .001). After controlling for potential confounding variables and propensity scores, patients who underwent surgery were less likely to die during the study period compared with women who did not undergo surgery (adjusted hazard ratio, .63, 95% confidence interval, .60–.66). Conclusions.—Analysis of the 1988–2003 SEER data indicated that extirpation of the primary breast tumor in patients with stage IV disease was associated with a marked reduction in risk of dying after controlling for variables associated with survival. The current goal of treatment for metastatic breast cancer is optimal palliation; surgery is reserved for symptomatic relief. However, several retrospective studies1-3 conducted in the past 5 years have demonstrated improved outcomes in patients diagnosed with stage IV breast cancer following surgical removal of the primary tumor. This study, which has a similar design and similar limitations to the previous studies, illustrates the same findings. Needless to say, this analysis adds to the evidence supporting the need for future prospective research evaluating survival out-
comes following extirpation of the primary tumor in patients with stage IV breast cancer. Furthermore, the specific surgical procedure performed in the settings of disease-negative margins, specific site(s) of metastasis, and radiation therapy should be incorporated into the analysis. These clinical trials will provide a better understanding of stage IV breast cancer and will subsequently support the development of new treatment options. J. L. Wagner, DO G. V. Babiera, MD
References 1. Rapiti E, Verkooijen HM, Vlastos G, et al. Complete excision of primary breast tumor improves survival of patients with metastatic breast cancer at diagnosis. J Clin Oncol. 2006;24: 2743-2749. 2. Khan SA, Stewart AK, Morrow M. Does aggressive local therapy improve survival in metastatic breast cancer? Surgery. 2002;132:620-626. 3. Babiera GV, Rao R, Feng L, et al. Effect of primary tumor extirpation in breast cancer patients who present with stage IV disease and an intact primary tumor. Ann Surg Oncol. 2006;13:776-782.
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Breast Diseases: A Year Book Quarterly Vol 19 No 1 2008
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Background.—Primary treatments for stage IV breast cancer are chemotherapy and radiation, with surgery usually reserved for tumor-related complications. We sought to determine whether surgical removal of the primary tumor provides a survival advantage for women with metastatic breast cancer. Methods.—We conducted a retrospective, population-based cohort study by using the 1988–2003 Surveillance, Epidemiology, and End Results (SEER) program data. By use of multivariate Cox regression models, overall survival in women with stage IV disease was compared between women who underwent surgical excision of their breast tumor with women who did not, controlling for potential confounding demographic, tumor- and treatment-related variables, and propensity scores (accounting for variables associated with the likelihood of having surgery). Results.—Of 9734 SEER patients with stage IV breast cancer, 47% under-
went breast cancer surgery and 53% did not. Median survival was longer for women who had surgery than for women who did not, both among women who were alive at the end of the study period (36.00 vs. 21.00 months; P < .001) and among women who had died during follow-up (18.00 vs. 7.00 months; P < .001). After controlling for potential confounding variables and propensity scores, patients who underwent surgery were less likely to die during the study period compared with women who did not undergo surgery (adjusted hazard ratio, .63, 95% confidence interval, .60–.66). Conclusions.—Analysis of the 1988–2003 SEER data indicated that extirpation of the primary breast tumor in patients with stage IV disease was associated with a marked reduction in risk of dying after controlling for variables associated with survival. The current goal of treatment for metastatic breast cancer is optimal palliation; surgery is reserved for symptomatic relief. However, several retrospective studies1-3 conducted in the past 5 years have demonstrated improved outcomes in patients diagnosed with stage IV breast cancer following surgical removal of the primary tumor. This study, which has a similar design and similar limitations to the previous studies, illustrates the same findings. Needless to say, this analysis adds to the evidence supporting the need for future prospective research evaluating survival out-
comes following extirpation of the primary tumor in patients with stage IV breast cancer. Furthermore, the specific surgical procedure performed in the settings of disease-negative margins, specific site(s) of metastasis, and radiation therapy should be incorporated into the analysis. These clinical trials will provide a better understanding of stage IV breast cancer and will subsequently support the development of new treatment options. J. L. Wagner, DO G. V. Babiera, MD
References 1. Rapiti E, Verkooijen HM, Vlastos G, et al. Complete excision of primary breast tumor improves survival of patients with metastatic breast cancer at diagnosis. J Clin Oncol. 2006;24: 2743-2749. 2. Khan SA, Stewart AK, Morrow M. Does aggressive local therapy improve survival in metastatic breast cancer? Surgery. 2002;132:620-626. 3. Babiera GV, Rao R, Feng L, et al. Effect of primary tumor extirpation in breast cancer patients who present with stage IV disease and an intact primary tumor. Ann Surg Oncol. 2006;13:776-782.
®
Breast Diseases: A Year Book Quarterly Vol 19 No 1 2008
53 53