A Survey of Patients with Inflammatory Skin Recurrence Corresponding to the Area of Previous Irradiation after Postoperative Radiotherapy for Breast Cancer

One of the unusual patterns of local recurrence in breast cancer patient is an inflammatory skin recurrence (ISR) sharply demarcating the area of previous radiation fields. To clarify the characteristics of this recurrence, we conducted a nationwide survey. We sent a survey to radiation oncologists at 200 institutions in Japan and received answers from 92. Of these, 24 institutions had some experience with patients who developed ISR affecting the previously irradiated area. The case details of 16 patients from 11 institutions were available and analyzed in this study. Eight patients experienced ISR after breast conservative therapy (groupA) and 8 patients experienced ISR after post-mastectomy radiotherapy (groupB). The postoperative pathological examination of groups A and B showed positive axillary lymph-nodes in 7/8 and 8/8 patients, positive lymphatic invasion in 4/7 and 7/8 patients, and ER status negative in 7/8 and 6/7 patients respectively. Median survival period was 266 days in groupA and 1105 days in groupB (p = 0.0001). Patients who developed the ISR tended to have several characteristics, including positive lymph-node metastases, intensive lymphatic invasion, and ER status negative. Physicians should contemplate the diagnosis of ISR next to radiation recall or radiation dermatitis, especially when the aforementioned risk factors are present.