Abstract
INTRODUCTION: Castleman's disease (CD) is a rare disorder characterized by benign angio follicular lymphoid hyperplasia, with gentle behavior. Its etiology and prevalence are unclear. It is usually found in the mediastinal area and it is rare to see this tumor in the retroperitoneum. PRESENTATION OF CASE: A 53 year old male with a retroperitoneal hypervascular calcified mass densely adherent to the psoas muscle that was accidentally encountered on a CT scan. Provisional diagnosis of retroperitoneal liposarcoma was made and the patient underwent an exploratory laparotomy. The histologic examination of the surgically resected specimen disclosed « a hyaline type of Castleman's disease ». DISCUSSION: Castleman's disease, is a rare heterogenous group of lymphoproliferative disorders that arises mostly in the mediastinum. The retroperitoneal localization is very rare. Clinically, CD can be subdivided into a localized form (unicentric disease) and a generalized form (multicentric disease) according to the number of lymph nodes involved. A careful histological and immunohistochemical examination of the tumor tissue after surgery is the only way for tumor diagnosis. CONCLUSION: Castelman's disease is a rare entity that has often benign and non invasive behavior, but remains a diagnostic challenge. There is no reliable diagnostic method and its definitive diagnosis is based on histopathology report. For treating the unicentric variant, radical surgical resection is considered to be the gold standard.