Mastectomy is unnecessary in many women with stage IV breast cancer, according to a study from Indian investigators, reported at the 2013 San Antonio Breast Cancer Symposium.1
The study randomly assigned 350 patients with metastatic breast cancer to mastectomy, complete axillary dissection, plus radiation therapy, vs no locoregional treatment, and found that the nonsurgical group had no worse survival than those who underwent mastectomy.
“The clinical conclusion would be that locoregional treatment of the primary tumor in women presenting with metastatic breast cancer did not result in any overall survival benefit, and hence should not be offered as a routine practice, but should be restricted as an option for palliation,” according to Rajendra A. Badwe, MD, Director of the Tata Memorial Hospital, Mumbai.
All patients received anthracyclines, with or without taxanes, and were stratified by metastatic site, number of metastases, and hormone receptor status, then randomized to either locoregional therapy or no locoregional therapy. For any progression, women received appropriate systemic treatment.
At 72 months, overall survival was 20.5% for the nonsurgical group and 19.2% for the surgical group. Local progression-free survival was better with surgery plus radiation (hazard ratio [HR] = 0.16), but distant progression-free survival was worse in this group (HR = 1.42; P = .01), Dr. Badwe reported. No differences were observed according to subgroup.
Biologic Hypothesis
The difference in local vs distant recurrence suggests that by removing the primary tumor, surgeons might be enabling the disease to spread, he said at a press briefing.
“The biologic fallout of this study is that surgical removal of the primary tumor in these women appears to confer a growth advantage on distant metastases,” he commented.
This was the conclusion, in fact, of a decades-old study from the laboratory of Bernard Fisher, MD, at the University of Pittsburgh. Dr. Fisher and his team reported that the removal of a primary tumor in mice appeared to release a growth factor that fostered the growth of distant tumors.2 They postulated that removal of the primary “can influence the outcome of a host to its tumor.” ■
Disclosure: Dr. Badwe reported no potential conflicts of interest.
References
1. Badwe R, Parmar V, Hawaldar R, et al: Surgical removal of primary tumor and axillary lymph nodes in women metastatic breast cancer at first presentation: A randomized controlled trial. 2013 San Antonio Breast Cancer Symposium. Abstract S2-02. Presented December 11, 2013.
2. Fisher B, Gunduz N, Coyle J, et al: Presence of a growth-stimulating factor in serum following primary tumor removal in mice. Cancer Res 49:1996-2001, 1989.
