Should internal mammary nodes be irradiated?

The optimal treatment of regional lymph nodes in the setting of postoperative adjuvant radiotherapy in unknown. Treating internal mammary lymph nodes is also controversial. Increased overall survival has been reported with post-mastectomy radiotherapy but contribution of internal mammary nodes radiotherapy was not specifically addressed. Irradiation of the cardiac structures with photon beams resulted in increased cardiac-related mortality but this is not the case for electron beams as shown in the literature. In this present review, we summarized the literature concern-ing internal mammary nodes irradiation.