Regional lymphomatoid papulosis of the breast restricted to an area of prior radiotherapy.

We report the case of a 59-year-old woman with type A regional lymphomatoid papulosis (LyP) that was localized to the left breast, a cutaneous area that had received radiotherapy for treatment of a carcinoma of the breast 5 years prior. This report is a rare example of regional LyP with all lesions located in an area of prior radiotherapy.