Postirradiation morphea: an underrecognized complication of treatment for breast cancer.

The most common cutaneous side effects of radiotherapy include radiodermatitis and radiation fibrosis. These are influenced by the type, dose, and pattern of delivery of the treatment. Distinct from these is postirradiation morphea (localized scleroderma), an idiosyncratic treatment-related phenomenon. Within the last 20 years, approximately 31 examples of postirradiation morphea after treatment for breast cancer were reported. We describe 5 new cases of this entity and integrate our findings with those in the literature. The mean age of the patients at the time of diagnosis of cancer was 58 years; all were left-sided and treated by local excision of the tumor, ipsilateral axillary lymph node dissection, and local radiotherapy. After an interval of 4 to 12 years, the patients developed morphea in the radiation portals, with extension beyond it in one instance. Recurrent breast carcinoma was suspected clinically in 2 cases. Microscopically, changes of morphea involved the dermis in all cases and the subcutis in 2. There was associated lichen sclerosus et atrophicus in 2 cases. Our data about management and outcome are limited, but 1 patient treated with potent topical steroids experienced gradual softening of the affected skin over a 5-year period, whereas another had a mastectomy for relief of painful induration of the breast. Our findings support existing theories about the pathogenesis of this condition and link it to those of sclerodermoid graft-versus-host disease. The purpose of our communication is to draw attention to this underrecognized complication of treatment for breast cancer.