Surgery of the primary lesion in patients with breast cancer having metastatic disease improves survival. A new retrospective study reveals that surgery  increases the medial survival from 14 months to 31 months. The doubling of median survival in this subgroup of patients is a very significant finding which now needs to be confirmed in larger phase III study.


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Surgical removal of the primary tumor in metastatic breast cancer improves survival. This was revealed in a study presented in the 15th Congress of the European Cancer Organization (ECCO 15) and the 34th European Society for Medical Oncology (34th ESMO) Multidisciplinary Congress: Abstract 5005. September 21, 2009. The author of the study,  Jetske Ruiterkamp, MD, said that removal of the tumor was associated with doubling of survival time.

Patients who underwent surgery had substantially longer median survival compared to the patients treated non surgically (31 months vs 14 months). The 5 year survival was 24.5% in surgery group vs 13.1% in non surgical group. This is a retrospective study done in Netherlands where 1 of 9 women are diagnosed with breast cancer, and of this population, 3% to 10% patients present with distant metastases at the time of their diagnosis. Among 15,769 women who were diagnosed with breast cancer in the south of the Netherlands between 1993 and 2004, 728 patients had distant metastases at their initial diagnosis. They represent 5% of all breast cancer patients in that region of the country. Approximately 40% of the patients with advanced-stage disease had undergone surgical removal of the primary tumor. There are two reasons for which  a primary lesion is removed in a patient with metastatic disease. One is that the tumor is causing symptoms and the second is the patient's desire for surgery. Usually when  women are doing well, they would like their tumour excised.

In the analysis conducted by the researchers patients were stratified  in subgroups defined by age, tumor stage, period of diagnosis, comorbidity, number of metastatic sites, use of locoregional radiotherapy and use of systemic treatment. The multivariate analysis revealed surgery to be an independent prognostic factor for overall survival.

The most probable explanation for this result is that the primary tumor may be releasing  cancer cells into the circulation and with surgery this source for cancer cells is removed. These findings are very interesting and important but as this is a retrospective study, randomized clinical trials are needed for conclusive evidence.