Abstract
A 14-year-old Japanese girl with Bourneville-Pringle phacomatosis was seen in our clinic. She had two giant tumors on her lower back. The surface of tumors showed a shagreen patch-like appearance. The histology of the excised tumors showed hyperplasia of irregularly interlacing collagen bundles and hypertrophy of each collagen fiber in a markedly thickened dermis. The subcutaneous fat tissue and collagen fibers of the interlobular septa were considerably increased. The tumors were regarded as an atypical shagreen patch with an extensive proliferation.
