A Case of Late-Onset Neurofibromatosis Speculated as Type 7

A 65-year-old woman developed freckling on her skin from axillary to inguinal regions at age 40. At age 55 and 63, she had respectively, a subcutaneous tumor from her right buttock and a left acoustic tumor removed, in both cases, histopathological analyses diagnosed a schwannoma. At age 65, she was admitted to our hospital for a detailed examination of an abdominal mass previously detected by MRI. The patient had no family history of schwannoma, nor presented café-au-lait skin spots. The abdominal mass was diagnosed as a retroperitoneal tumor by enhanced-CT-scan, MRI and FDG-PET/CT. Needle biopsy examinations confirmed a schwannoma diagnosis. Thus, we considered this as a very rare case of late-onset neurofibromatosis speculated as type 7.