Biopsy results of new calcifications in the postirradiated breast

A breast biopsy was performed in 19 patients for the finding of new mammographic calcifications without an associated palpable or mammographic mass after breast-conserving surgery and definitive irradiation for early stage breast cancer. The interval postradiotherapy was 9 to 96 months with a median of 34 months. Eleven of the biopsy specimens (58%) were positive for recurrent breast cancer and eight (42%) were negative. The pathologic results from the positive biopsy specimens showed four with invasive ductal carcinoma, two with microinvasive ductal carcinoma, four with intraductal carcinoma, and one with lobular carcinoma in situ (LCIS). Treatment consisted of mastectomy in eight patients, mastectomy plus chemotherapy in one patient, and biopsy for the patient with LCIS. One patient refused a recommended mastectomy. All 11 patients with recurrent carcinoma are alive with no evidence of disease after salvage therapy, although follow-up is short (median, 14 months; range, 0-48 months). Calcifications which developed in a quadrant different from the initial tumor tended to be malignant with four of five having a positive biopsy result. Microcalcifications were not commonly associated with the initial tumor with only five of 19 having microcalcifications. These results show that the development of new calcifications in the postirradiated breast is associated with a positive biopsy rate of 58% and that the tumors which are found tend to be early and potentially salvageable. The positive biopsy rate of 58% in the postirradiated breast is in marked contrast to the lower positive biopsy rate for microcalcifications in the nonirradiated breast as reported in the literature.