A Giant Peritoneal Loose Body
A 50-year-old man underwent a routine medical examination, at which time multiple gallstones and an incidental pelvic mass were detected on computed tomography (CT) scanning of the abdomen and pelvis. An ovoid, well-defined mass in the pelvic cavity was detected consisting of central dense, heterogeneous calcifications and peripheral soft tissue (). The mass compressed the bladder wall (). There was a distinct fat plane around the mass, which did not appear to originate from or invade any of the adjacent organs. The patient denied any symptoms and the presence of any past medical problems. Laboratory tests were all within the normal range. Based on the radiologic findings, a preoperative diagnosis of peritoneal calcifying fibrous pseudotumor was suggested. On laparoscopic exploration, a well-circumscribed, fist-sized, hard, and free mass was found in the pelvic cavity. In addition, some of the epiploic appendices attached to the sigmoid colon were calcified with constricted stalks and were on the verge of becoming detached. All other abdominal and pelvic viscera were unremarkable. Laparoscopic cholecystectomy and pelvic mass removal were performed.\nGrossly, the pelvic mass measured 7.5×7.0×6.8 cm and weighed 160 g; it was a white-to-pale yellow, hard, glistening concretion that looked like a boiled egg with the shell removed (). The cut surface of the concretion revealed a central 1.5 cm-diameter nucleus of a creamy, cheese-like material surrounded by white-to-yellow lamellar structures (). Microscopically, the concretion consisted of central necrotic fatty tissue () surrounded by many layers of concentrically laminated, eosinophilic, acellular, fibrous material () with scattered blue-to-black lakes of microcalcifications (). Masson's trichrome stained the fibrous material blue, indicating an abundance of collagen (). There were variable-sized vacuoles and empty clefts interspersed among the laminated material that could have represented vestiges of aged fat necrosis. The surface was partially lined by mesothelial cells. No inflammatory or foreign body reactions, parasites, polarizable substances, or identifiable tumor tissues were present in the specimen. These histopathological findings were characteristic of a giant PLB. The patient had an uneventful recovery. He was discharged from the hospital five days after surgery.