Second lumpectomy for breast cancer reduces survival rates

October 2, 2008

A majority of women with breast cancer today are candidates for lumpectomy, allowing for conservation of most of their breast tissue. Results of a UC Davis study, however, show that a number of women whose cancer recurs in the same breast are treated with a second lumpectomy rather than a mastectomy, defying current treatment recommendations and cutting the number of years those women survive in half.

"We were surprised to find that so many women in our study — almost a quarter of them — had received another lumpectomy rather than a mastectomy," said Steven Chen, a UC Davis Cancer Center surgical oncologist and lead author of the study, which appears in the October issue of the American Journal of Surgery. "It's likely that patients are asking for lumpectomies when their cancer is diagnosed a second time, and their doctors are simply complying with that request. Whatever the reason, that decision can shorten life spans."

Chen and study co-author, Steve Martinez, also a UC Davis Cancer Center surgical oncologist, gathered data from the National Cancer Institute's Surveillance, Epidemiology and End Results database, which includes information on all cancers diagnosed in selected regions throughout the nation. Their study included 747 patients who previously received breast-conservation therapy and were diagnosed with cancer a second time in the same breast between 1988 and 2004.

The authors found that women who had mastectomies had a 78 percent survival rate after five years, while those who had second lumpectomies had a 67 percent survival rate. The 10-year survival rates were 62 percent for those who had mastectomies and 57 percent for those who had second lumpectomies. In all, 24 percent of women with recurrent breast cancer in the same breast had second lumpectomies.

The researchers went on to calculate the risk of dying for mastectomy patients compared to lumpectomy patients. They found that, after adjusting for factors that affect survival, there will be half as many survivors at any given time in the lumpectomy group versus the mastectomy group.

Chen explained that a mastectomy is the generally accepted surgical treatment for a second cancer because whole breast radiation, which typically accompanies a lumpectomy, is not usually recommended twice in a lifetime. This new study shows as well that there is a survival advantage to those who choose a mastectomy.

According to Martinez, knowledge of breast cancer and its treatments are continuously advancing, and second lumpectomies could at some point become a viable option.

"As therapy for breast cancer becomes more targeted and researchers come closer to identifying those factors that make some breast cancers more aggressive than others, we may have the option of recommending second and even third lumpectomies in select cases in the future. Until then, mastectomy remains the best option for women experiencing a same-breast recurrence of their breast cancer," he said.

Source: University of California - Davis