Case 219: Pelvic Actinomycosis Mimicking Malignant Tumor.

A 53-year-old woman presented with a 3-month history of left inguinocrural and lumbar pain and anorexia with weight loss. No fever was reported. The patient had no prior pelvic surgery. Physical examination revealed a palpable nontender mass in the left groin area. There was no bloody or purulent discharge. Laboratory findings revealed inflammation with an increased C-reactive protein level (127 mg/L [1209 nmol/L]), leukocytosis (13 800/mm(3)), and microcytic anemia (hemoglobin level, 7.2 g/dL). Computed tomography (CT), fluorine 18 ((18)F) fluorodeoxyglucose (FDG) positron emission tomography (PET)/CT, and magnetic resonance (MR) imaging were performed.