Prediction of Recurrence for Advanced Breast Cancer: Traditional and Contemporary Pathologic and Molecular Markers

Abstract

Approximately 50% of patient with breast cancer ultimately develop metastases, among which only 10% to 15% of patients live 5 years or more. Patients with locally advanced (stage III) breast cancer have a 5-year survival rate of approximately 20% to 30%. Thus, despite high remission rates obtained with current therapies, the poor long-term results associated with the apparent plateau of response achievable with systemic therapies emphasize the necessity of identifying accurate prognostic factors for this group of patients. This will allow an informed discussion with the individual patient. In addition, prognostic information could be used to guide the therapy and also to identify those subgroups of patients who may benefit with less-aggressive therapies. Furthermore, in the context of randomized studies, prognostic factors can be used to stratify patients. Prognostic factors have been extensively studied in early-stage breast cancer. In comparison, only a few studies exist on biologic prognostic factors in advanced breast cancer. Based on the limited information available, it appears that the biologic factors prognostic for locally advanced breast cancer are similar to those reported for early-stage breast cancer. Apparently, certain factors have a prognostic value irrespective of the stage of the disease at the time of presentation. This would then suggest that certain factors maintain their significance as the breast cancer progresses from an overtly local to a systemic disease. It is already well recognized that histologic grade is a significant prognostic factor for early-stage as well as metastatic breast disease. Hormone receptors have been reported to be of prognostic value at all stages of disease. Proliferation rate assessed by a variety of techniques as well as determination of the Nottingham Primary Prognostic Index provides important information about the rate of the growth of the tumor. Thymidine labeling index and S-phase fraction also provide information in regard to response to chemotherapy. DNA ploidy has been reported to be of significance in prediction of response to adjuvant chemotherapy and to a lesser extent to hormone therapy. The value of DNA ploidy in relation to survival in advanced breast cancer, however, remains controversial. Other prognostic factors such as oncogenes, tumor suppressor genes, and growth factors have also shown some predictive value in advanced breast cancer. Similar to what has also been suggested in early breast cancer, much research still needs to be done to clarify the role of currently available prognostic factors and to identify new, more powerful discriminants.(ABSTRACT TRUNCATED AT 400 WORDS)