en Pediatric Hematology & Oncology Pediatric Hematology & Oncology پژوهشي Original Article Rosai-Dorfman disease or sinus histiocytosis with massive lymphadenopathy is a rare disorder that typically manifests as lymphadenopathy and systemic symptoms whose etiology remains poorly elucidated. The diagnosis is based on immunohistochemistry. Its treatment is poorly defined but the prognosis is usually favorable. Here we report a 14 year old boy who presented with massive bilateral cervical lymphadenopathy. Histopathological examination demonstrated lymphophagocytosis (emperipolesis) consistent with a diagnosis of Rosai-Dorfman disease. The clinical and histological aspects of the disease are discussed as a rare cause of lymphadenopathy. Key Words: Rosai-Dorfman disease, emperipolesis, case, Iran. Rosai-Dorfman disease, emperipolesis, case, Iran 155 158 http://ijbc.ir/browse.php?a_code=A-10-1-74&slc_lang=en&sid=1 Bibi Shahin Shamsian 10031947532846002373 10031947532846002373 Yes Nahid Arabi 10031947532846002374 10031947532846002374 No Maryam Kazemi Aghdam 10031947532846002375 10031947532846002375 No Mohsen Rouzrokh 10031947532846002376 10031947532846002376 No Nozar Ghojehvand 10031947532846002377 10031947532846002377 No Roksana Azma 10031947532846002378 10031947532846002378 No Mohammad Kaji Yazdi 10031947532846002379 10031947532846002379 No Samin Alavi 10031947532846002380 10031947532846002380 No Mohammad Taghi Arzanian 10031947532846002381 10031947532846002381 No