Chemotherapy of breast cancer: current views and results

The paper critically reviews major accomplishments achieved with the use of chemotherapy in the treatment of various stages of breast cancer. In spite of innumerable clinical trials, there is no evidence that in advanced breast cancer the addition of more drugs, either in concomitant, sequential or alternating fashion, to known effective combinations, was able to significantly improve the incidence and the magnitude of objective response or its median duration or survival. The addition of endocrine therapy to chemotherapy has failed so far to improve the most important end-point, i.e. total survival. Second-line chemotherapy is only moderately effective for a fairly short period of time. Thus, in women with advanced breast cancer excessive tumor cell burden and permanent drug resistance remain the major obstacles to obtaining complete remission and long-term disease free survival. In the adjuvant setting, the initial trials with combination chemotherapy have achieved consistent results, particularly in women with minimal axillary node involvement. Unless a woman has undergone a surgical breast-saving procedure, postoperative radiotherapy does not appear to play an important therapeutic role, either with or without concomitant or sequential chemotherapy. Present results would suggest that in advanced breast cancer little progress can be expected in the near future. Therefore, medical oncologists should focus on the correct application of established drug regimens, using a sequential flow of hormonal manipulations and cytotoxic chemotherapy. In high-risk groups, full dose adjuvant polydrug therapy given for a relatively short period of time appears to be at present the only means able to significantly decrease the failure rate following local regional treatment. Present consistent achievements, which appear devoid of important delay morbidity (e.g. cancerogenesis, chronic organ damage) will require further clinical research to identify more effective and less toxic treatments.