Peritoneal Super Scan on 18F-FDG PET/CT in two patients with Lymphoma.

Peritoneal lymphomatosis is an extremely rare presentation of lymphoma. Due to its relative low frequency, it receives much less attention than peritoneal carcinomatosis. The challenge is to differentiate between lymphomatosis and carcinomatosis, as well as peritoneal tuberculosis or other pathologic entities within the peritoneal cavity based essentially on radiologic features. 18F-FDG PET/CT is the main imaging modality for staging and monitoring response to treatment in lymphoma. Peritoneal lymphomatosis is most often associated to aggressive histological subtypes of high-grade lymphoma which are reputed high FDG uptake. We report two cases of Burkitt's lymphoma and diffuse large B cell lymphoma (DLBCL), with intense FDG uptake involving the entire peritoneum and decreased FDG activity of the rest of the body including brain and kidneys, giving it an appearance of "peritoneal super scan", follow up FDG PET/CT showed the disappearance of the peritoneal lymphomatosis and the reappearance of cerebral and urinary activity synonym of complete metabolic response.