Unicentric Castleman's Disease Presenting as Retroperitoneum Lump

Castleman disease is a rare lymphoproliferative disorder, also known as giant lymph node hyperplasia or angiofollicular lymph node hyperplasia. Clinically, Castleman disease is of two types: localised/unicentric type and multicentric/systemic type. Unicentric or localised Castleman disease affect a single lymph node or group of lymph nodes. The multicentric type affects two or more groups of lymph node in different part of the body. It can also affect organs containing lymphoid tissue. Histologically it is classified as hyaline vascular variant, plasma cell variant and a mixed variant. Clinical symptoms may vary from asymptomatic to symptomatic lymphadenopathy accompanied by fever, anaemia fatigue, abdominal or thoracic pain and weight loss. There is no specific test to diagnose Castleman disease. We report a case of 16 years old male who presented with a painless lump in left lumbar region without any constitutional symptoms. CECT suggested a retroperitoneal lump with calcification. Laparotomy was done and complete excision of mass done. Histopathological examination of excised tissue suggested Castleman disease of hyaline vascular variant. After six month of follow up, the patient has no complain.