We present the case of a patient with patch-stage mycosis fungoides who developed ulcerative tumors compatible with large cell transformation. Tumor cells were positive for CD30 and CXCR3 and negative for CCR3, and subsequently exhibited spontaneous regression. Thus, large cell transformation in early mycosis fungoides may not indicate poor prognosis.
Antigenic competition in the skin is a phenomenon in which the current dermatitis is distributed away from the area of previously existing dermatitis. We experienced antigenic competition-like phenomenon in bullous pemphigoid. Our case differs from typical presentations of antigenic competition, since the responsible antigen was the same.