17 Jan Metastatic Breast Cancer: Surgical Removal of Primary Tumor and Axillary Nodes
MedicalResearch.com Interview with:
Dr. R.A. Badwe, MS
Director, Tata Memorial Centre
E. Borges Marg, Parel
Mumbai 400 012
MedicalResearch.com: What are the main findings of the study?
Answer: The trial was a randomized control study involving 350 women with per primum metastatic breast cancer. These women were divided into two groups from February 2005 to May 2013. One group underwent surgery and radiotherapy (LRT) (n=173) while another group of 177 women were spared these (no LRT). Both groups had undergone six successful rounds of chemotherapy before their recruitment into the trial. Women who underwent surgery had the primary breast tumour and lymph nodes removed, followed by locoregional radiation therapy.
The primary endpoint of the study was overall survival (OS). At a median follow-up of 17 months, no difference was observed in OS between the groups; the OS rates were 19.2% and 20.5%, respectively, (HR = 1.04; 95%CI, 0.80-1.34; P = 0.79). The lack of a survival benefit is due to a trade-off between local control and distant disease progression. The results indicated that women who underwent surgery and had improved locoregional control and significantly worse distant progression-free survival compared with women who did not undergo surgery (HR = 1.41; 95% CI, 1.08-1.85; P = .01). Progression of distant disease was 42% more likely (P = .01) in the LRT arm whereas the risk of local progression was 84% lower with LRT.
MedicalResearch.com: Were any of the findings unexpected?
Answer: Preclinical evidence by fisher et al suggests that removal of a primary tumor may facilitate growth of metastatic disease. Fisher et al found that metastasis increased in mice after tumor removal due to a serum growth factor capable of stimulating distant cells (Cancer Res. 1989;49(8):1996-2001).
Retrospective institutional series and population-based series in clinical cohorts, in contrast, suggest favorable impact of surgery and/or local radiotherapy in these patients. A systematic review of these studies showed a 35% reduction in deaths in patients who have had surgical intervention. The retrospective analyses however are fraught with selection biases.
The present study results support the preclinical evidence and refute the results of the systematic review of the retrospective studies, which showed a 35% reduction in deaths in patients who have had surgical intervention.
MedicalResearch.com: What should clinicians and patients take away from your report
Answer: The take home message is that the indication for surgery of the primary tumor in women with metastatic breast cancer should be would be limited to palliation, for fungating or bleeding primary breast tumors.
MedicalResearch.com: What recommendations do you have for future research as a result of this study?
Answer: We recommend that surgery in metastatic breast cancer be reserved for only the palliative setting.
But simultaneously we feel that we need to evaluate why the distant tumor grows faster after removal of the primary. The possible inhibitory effect that the primary tumor exerts needs to be evaluated.
Additionally pooled analyses from the various ongoing studies may yield sufficient power to detect smaller difference sand give a complete answer.
Citation: Abstract Presented at:
San Antonio Breast Cancer Symposium
Badwe R, et al “Surgical removal of primary tumor and axillary lymph nodes in women with metastatic breast cancer at first presentation: A randomized controlled trial” SABCS 2013; Abstract S2-02.