DOI: 10.14260/jemds/2015/1221 CASE REPORT J of Evolution of Med and Dent Sci/ eISSN- 2278-4802, pISSN- 2278-4748/ Vol. 4/ Issue 48/ June 15, 2015 Page 8425 A RARE CASE OF DEDIFFERENTIATED LIPOSARCOMA WITH CHONDROSARCOMATOUS DEDIFFERENTIATION Tanu Agrawal 1 , Kanchan Garg 2 , Dupinder Kaur 3 , S. K. Sagar 4 HOW TO CITE THIS ARTICLE: Tanu Agrawal, Kanchan Garg, Dupinder Kaur, S. K. Sagar. “A Rare Case of Dedifferentiated Liposarcoma with Chondrosarcomatous Dedifferentiation”. Journal of Evolution of Medical and Dental Sciences 2015; Vol. 4, Issue 48, June 15; Page: 8425-8429, DOI: 10.14260/jemds/2015/1221 ABSTRACT: We report a rare case of dedifferentiated liposarcoma with chondrosarcomatous components. A 39 years old male presenting with a left buttock swelling underwent a wide tumor excision. The histopathological diagnosis was dedifferentiated liposarcoma (DDLS) with chondrosar- comatous dedifferentiation. Histologically, DDLS is represented by the abrupt transition from well differentiated liposarcoma to a region of non-lipogenic sarcoma. Dedifferentiation frequently resembles a malignant fibrous histiocytoma-like pleomorphic sarcoma. Divergent differentiation with chondrosarcomatous components is very rare. We present here a case of gluteal dedifferentiated liposarcoma with chondrosarcomatous dedifferentiation because of its extreme rarity. KEYWORDS: Dedifferentiated liposarcoma, chondrosarcoma, gluteal. INTRODUCTION: Liposarcomas are the most frequent soft tissue sarcoma in adults. Liposarcomas are usually large and occur most frequently in the lower extremities; retroperitoneal, perirenal, and mesenteric region; and shoulder area. 1 Included in the general category of liposarcoma is a number of subtypes that are histologically, biologically, cytogenetically and by molecular analyses distinct from one another. According to World Health Organization, it is classified into four subtypes: Atypical Lipomatous Neoplasm/ Well Differentiated Liposarcoma, Myxoid/Round cell, Dedifferentiated and Pleomorphic liposarcoma. 2 Dedifferentiated, round cell and pleomorphic liposarcoma are high-grade, aggressive tumors with metastatic potential while well differentiated and myxoid liposarcoma are low-grade tumors that follow a more indolent clinical course. 3 DDLS has 2 distinct components, a well-differentiated lipomatous component and a dedifferentiated non-lipomatous component composed of sarcomas, such as myxofibrosarcomas or other spindle-cell sarcomas. Dedifferentiated component exhibiting chondrosarcomatous dedifferentiation is very rare with only few cases reported in literature. 4,5 CASE REPORT: A 49 years old male presented with complaint of swelling in the left buttock. He had noted the swelling approximately 6 months earlier but in last fifteen days before presentation it had rapidly increased in size. It was associated with mild intermittent pain. He denied any associated trauma. Physical examination revealed a firm, non-tender and non- mobile mass measuring 10x8 cm with normal overlying integument in the left gluteal region. Complete blood cell count and routine biochemical investigations were within normal limits. Fine needle aspiration cytology was done which was inconclusive. Magnetic resonance imaging revealed a large heterogeneous mass in the left gluteal muscle with interspersed cystic and necrotic areas suggestive of soft tissue sarcoma. Patient underwent wide excision of left gluteal region and the resected specimen was sent for histopathological analysis.