Repeat high-dose external beam irradiation for in-breast tumor recurrence after previous lumpectomy and whole breast irradiation.

PURPOSE: To determine whether excision of an in-breast tumor recurrence (IBTR) plus 5000 cGy in 25 fractions to the new operative area is both tolerated and effective as treatment for an IBTR after previous lumpectomy and whole breast irradiation. METHODS AND MATERIALS: Thirty-nine women with an IBTR after lumpectomy and breast irradiation for invasive carcinoma (n = 31) or ductal carcinoma in situ (n = 8) were treated with excision of the IBTR and radiotherapy (RT), 5000 cGy in 25 fractions, to the operative area using electrons of appropriate energy. The interval from completion of the first course of RT to diagnosis of the IBTR ranged from 16 to 291 months (median 63).
RESULTS: The repeat course of RT to the new operative area was well tolerated in all patients, and no late sequelae occurred other than skin pigmentation changes. Eight patients, including 2 with suspicious bone scans at the time of IBTR, developed distant metastases, and 7 died 21-71 months (median 48) after retreatment. One patient was alive with distant metastases at 27 months after retreatment. Four of the 8 patients who developed distant metastases also had a second IBTR, and 3 died with persistent disease in the breast. An additional 4 patients, for a total of 8, had a second IBTR. Three were alive and free of disease after mastectomy, and 1 was alive and free of disease after mastectomy and additional RT for chest wall recurrence. An additional patient developed recurrence in the axilla 9 months after reirradiation and was treated with surgery; she died free of disease at 63 months. One patient underwent mastectomy for suspected persistent disease 2 months after completion of repeat RT; no evidence of recurrent tumor was found in the removed breast. Thus, 30 women (76.9%) had an intact breast free of tumor at death or at last follow-up 1-180 months (median 51.5) after reirradiation. Using the Kaplan-Meier life table analysis, the estimated overall and disease-free 5-year survival rate for the 39 patients was 77.9% and 68.5%, respectively.
CONCLUSION: For select patients with an IBTR after lumpectomy and breast irradiation, excision of the IBTR followed by repeat external beam RT to the operative area may be an acceptable alternative to mastectomy.