リンパ節転移と鑑別が困難であった閉鎖神経原発神経鞘腫の1例

Abstract

A 58-year-old man, received polypectomy to evaluate the polyp of sigmoid colon. Pathological examination of the specimen revealed non-invasive adenocarcinoma. Systemic work up including abdominal computed tomography (CT) demonstrated a bladder tumor 11×18 mm in diameterassociated with left obturator lymph node swelling (16×14 mm). In the preoperative staging, this nodule was suspected to be lymph node metastasis, even though both cancers were diagnosed to be early stage. Transurethral resection of bladder tumor (TUR-Bt) and lymph node open biopsy were performed. The final diagnosis of bladdertumorwas pTa, urothelial cancergr ade 2 and low grade. The nodule had originated from the obturator nerve itself, and pathological diagnosis demonstrated benign schwannoma. To the best of our knowledge, this is the 14th report of benign schwannoma of the obturator nerve in Japan.