Normal-sized ovary carcinoma syndrome (NOCS) detected with FDG-PET/CT.

Abstract Normal-sized ovary carcinoma syndrome (NOCS) is an ovarian cancer with ovaries being of normal size, accompanied by diffuse metastatic disease of the peritoneal cavity. A 39-year-old woman presented with lower abdominal pains. The computed tomopraphy (CT) of the chest, esophagogastroduodenography, and colonoscopy showed no remarkable findings. Amagnetic resonance imaging (MRI) displayed a slightly enlarged right ovary, thickening of the peritoneum, and massive ascites. The right ovary showed high intensity on T2 images and scattered low intensity spots on diffusion-weighted images. The cytology of ascites suspected adenocarcinoma cells. A positron emission tomography (PET) and CT using 18F-fluorodeoxyglucose (FDG) demonstrated markedly increased FDG uptake at the right ovary and peritoneum. The presumptive diagnosis of normal-sized ovary carcinoma syndrome was made. She underwent a total hysterectomy, bilateral salpingo-oophorectomy, pelvic lymphadenectomy, and partial omentectomy. The pathological examination revealed serous cystadenocarcinoma of the right ovary. FDG-PET/CT is useful for the detection of NOCS.