Chemotherapy of breast cancer

Carcinoma of the breast will prove fatal to over 37,000 women in the United States in 1983, despite attempts at early diagnosis. Hormonal manipulation, known to provide effective palliation for many years, can now be effectively aimed at receptor positive women who have a 50-70% chance of responding. Newer agents, such as tamoxifen and aminoglutethimide offer the benefits of older treatments with less morbidity. Investigations of drugs acting at the level of the central nervous system are ongoing. Single agent chemotherapy is clearly effective in causing tumor regression, but effective combination chemotherapy provides more responses and a longer duration of response. The most effective combination regimens at present contain doxorubicin. Pharmacologic studies at the cellular level can be expected to provide more effective combinations. The most effective way to combine hormonal and chemotherapeutic treatments is not known. In receptor positive women without life-threatening disease, beginning with hormonal treatment may be effective in providing palliation at low toxic cost without jeopardizing overall survival. New efforts to cure clinically manifest metastatic breast cancer may eschew palliation as a prime goal. Techniques of synchronizing and of stimulating breast cancer to increase its susceptibility to cytotoxic drugs are under investigation. Immunotherapy is not established as a beneficial modality in the treatment of breast cancer, although levamisole has led to suggestive benefit in small controlled trials. The use of chemotherapy, and possibly of some hormonal treatments in appropriate patients, as an adjuvant to surgery prolongs disease-free survival. This approach, using established chemotherapeutic and hormonal agents when the metastatic disease is subclinical, is consonant with abundant evidence from experimental systems and other human cancers that are curable. Expectation of curing human breast cancer will likely require aggressive action at the time when the total body tumor burden is at a minimum.