New research presented at the seventh European Breast Cancer Conference (EBCC7) in Spain has reported that recurrence of breast cancer in the breast, chest wall, or lymph nodes five years or more after lumpectomy or other breast-conserving surgery indicates poor long-term prognosis. Locoregional recurrence after breast-conserving therapy is known to be an independent risk factor for unfavorable long-term outcome. However, the prognostic significance of such a recurrence after a long period of remission has not been determined. The study included data pooled from four trials including 7,749 patients with early stage breast cancer with a median follow-up period of 10.9 years. Distant disease-free survival and overall survival were the long-term outcome variables.

Locoregional recurrence, tumor size, lymph node status, age, estrogen receptor status and chemotherapy were all observed to be independent prognostic factors with significant impact on long-term survival five to 10 years after initial diagnosis. However, in patients that were in remission for more than 10 years after initial breast cancer treatment, locoregional recurrence was the only independent prognostic factor. The risk of metastasis was four times higher for women with locoregional recurrence after 10 years compared to early stage survivors without such a recurrence and the risk of death was eight times higher. The authors conclude that locoregional recurrence after breast-conserving therapy is a very strong independent risk factor for poor outcome even after a very long event-free interval in early stage breast cancer patients. They further suggest that locoregional recurrence may be associated with distant disease after a long event free interval rather than a cause of subsequent metastasis.

Implications of late recurrence

A recurrence in or near the breast many years after the initial diagnosis and treatment of breast cancer is a very serious event and should be treated differently from the initial tumor, regardless of any potentially favorable characteristics such as small size. Based on the available evidence, the tumor should be surgically removed if at all possible. Furthermore, hormone receptor status and other tumor characteristics should be determined to help optimize the type of chemotherapy and other treatments the new tumor may have a different profile from the original cancer. The study indicates that very aggressive systemic treatment may be appropriate. While the possibility of progression to stage IV disease is much higher than if locoregional recurrence had not occurred, it is by no means inevitable, and every effort should be made to reduce the likelihood of this outcome.