Resection in Women with Stage IV Breast Cancer Improves Survival

Jetske Ruiterkamp, surgical resident, Jeroen Bosch Hospital, of The Netherlands and colleagues presented findings from a retrospective study that compared the rate of 5-year overall survival (OS) and reduction in the risk of death in women with stage IV breast cancer who underwent resection of their tumor compared with those who did not. Surgery was associated with a 40% reduction in the risk of mortality, overall.

The study analyzed data for 728 women who had distant metastases at the time of presentation. Dr Ruiterkamp noted that this group of patients, which makes up 3% to 10% of breast cancer cases, has a particularly poor prognosis. "Within a month after the diagnosis of the primary tumor," she said, "these patients are also diagnosed with metastasis." She added that median survival for these patients is typically 1 to 2 years, with treatment focused on maintaining or improving quality of life.

Of the 728 women included in the study, 40% underwent surgery for their primary tumor. Women who had surgery tended to be younger and were less likely to have more than one site of metastases and less likely to have a comorbidity. They were more likely than the women who did not have surgery to be symptomatic and to undergo radiotherapy or systemic therapy.

Median OS for the women who had surgery was 31 months compared with 14 months for women who did not have surgery. Women who had surgery also had a significantly improved rate of 5-year OS, at 24.5% compared with 13.1% for women who did not have surgery. This represented a 40% reduction in the risk of death, and multivariate analyses concluded that surgical resection was an independent prognostic factor for OS (HR = 0.62).

According to Dr Ruiterkamp, possible reasons for the better survival seen in the women who had surgery might be a reduction of circulating tumor cells that resulted from excising the primary tumor. “It is also possible that surgery reactive the immune system,” she said.

Dr Ruiterkamp acknowledged that because the study was retrospective and patients were selected for different reasons, this might have introduced bias into the findings. She said the results, however, suggest a randomized controlled trial is needed to determine definitively whether surgery improves survival in women with stage IV breast cancer. This study is considered one of the best of ECCO/ESMO.

ECCO/ESMO Abstract O-5005