Chest wall recurrence location and the lower-bound target of preventive radiotherapy after transverse incision in modified radical mastectomy.

We investigated the relationship between the lower-bound target of preventive radiation to the chest wall after modified radical mastectomy with a transverse incision and preoperative breast carcinoma characteristics to provide a basis for reducing radiation injury to neighboring tissues and individualizing preventive chest wall radiation targets. We analyzed the relationship between clinical stage, pathology, diseased region, condition of vessel tumor embolus, sex hormone levels, HER-2 expression levels, receipt of chemotherapy, and the distance of local chest wall recurrence under the edge of the transverse incision in 112 patients with local chest wall recurrence after radical mastectomy. There were 64 cases (57.1%) with local chest wall recurrence within 3 cm below the transverse incision fringe, 31 cases (27.7%) within 3-5 cm, 14 cases (12.5%) within 5-7 cm, and 3 cases (2.7%) exceeded 7 cm. There were statistically significant correlations between the distance from the focus of the chest wall recurrence to the inferior margin of the transverse incision and the T stage, HER-2 expression levels, and receipt of chemotherapy. For more than 97% of patients undergoing radical mastectomy with a transverse incision, the distance of local chest wall recurrence under the edge of the transverse incision was less than 7 cm. To accomplish individualized treatment in defining radiotherapy targets, we should pay attention to T stage, HER- 2 expression levels, and the receipt of chemotherapy when determining the lower-bound location of the target for preventive chest wall radiation after modified radical mastectomy with a transverse incision.