Lactation after conservative breast surgery combined with radiation therapy.

Radiosensitivity of the mammary gland and the effect of therapeutic radiation on lactation has not been defined. To investigate lactation following conservative surgical management and megavoltage radiation treatments for early breast carcinoma, data were collected from a national survey of 2,582 members of the American Society of Therapeutic Radiology and Oncology. This study reports 53 women who became pregnant after lumpectomy, axillary dissection, and radiation treatments with an average dose of 180-200 cGy. The mean daily total dose to the breast was 49.4 Gy and to the boost area 15 cGy either with electrons or implant. Of these patients, 34% were able to exhibit some form of lactation from the irradiated breast; 24.5% were able to successfully breast-feed from the involved breast. Results of the study document that bilateral lactation can successfully occur after conservative surgery and radiation therapy in approximately 1 in 4 women.