Irradiation is indicated for patients undergoing
mastectomy as surgical management for
breast cancer treatment when clinical or pathologic
tumor and nodal features predict risk of local/regional recurrence. Such features include:
tumor size >/= 5 cm, inadequate
surgical margins; skin, facial, or skeletal muscle invasion; dermal lymphatic invasion; poorly differentiated
tumor histology; four or more lymph nodes positive; gross extracapsular
tumor nodal extension into soft tissues; and matted lymph nodes or enlarged lymph nodes > 2 cm. Patients who were treated with irradiation after
mastectomy can develop local/regional recurrences despite such adjuvant
therapy. General management for chest wall and nodal recurrences is structured on the extent and volume of local/regional disease, the absence of distant
metastases, the general health of the patient, and the extent of prior local/regional
therapies, especially irradiation. Management of local/regional recurrence in the setting of no prior irradiation includes
tumor debulking by systemic or surgical treatment followed by comprehensive chest wall and regional
lymphatic irradiation. Doses are selected by tissue tolerances and volume of remaining disease. The management strategy for the patient with a history of irradiation parallels the nonirradiated patient with respect to systemic and surgical
therapies to debulk the
tumor to maximal response or no gross clinical disease. Radiation field design is determined by prior
therapies. Doses to these fields are adjusted to normal tissue tolerance. Irradiation is given with a sensitizer such as
hyperthermia or
5-fluorouracil chemotherapy. Use of
radiation sensitizers can allow for a more meaningful
biologic tumor effect when normal tissue tolerances prohibit delivery of standard
tumor doses.
Hyperthermia has been used effectively to promote complete
tumor responses with use of irradiation in re-treatment cases.