New diagnostic, staging, and therapeutic aspects of early breast cancer.

Many advances have occurred in breast cancer through research and clinical trials. More confidence in new biological consumptions about invasive breast cancer indicate that: (1) details of the primary breast cancer do not control survival; (2) breast-only failures after local excision do not bias against survival; and (3) cancer cell dissemination occurs at the same time via both lymphatic and hematogenous routes. Early detection with mammographic screening has indicated a greater number of smaller breast cancers, including sharp increases in ductal carcinoma in situ (DCIS). With proper analysis and control, DCIS of limited extent can be treated by local excision with or without radiation. Invasive breast cancer of limited extent can frequently be managed by lumpectomy and radiation therapy with survival rates equivalent to the more traditional mastectomy. Patient desires regarding breast preservation and quality of life are paramount. Risk: benefit analyses for individual patients need to be emphasized in issues of breast preservation and in selecting adjuvant therapy, both regional (radiotherapy) and systemic (chemotherapy) and hormonal therapy). We are entering an era of highly selective therapy based on more sophisticated analysis of the primary cancer. In the future, not only statistical predictions of outcome as achieved by flow cytometry, for example, will be more widely used, but individual prognostic factors may be developed such as with oncogene expression. Such individual prognostic factors will enable more selective therapy.