Chondrolipoma of the Knee: A Case Report

ABSTRACT

Chondrolipoma is a benign tumor composed of mature adipose tissue and mature chondrocytes, and very rarely found. The patient, a 36-year-old woman, presented with a firm, walnut sized, mild tender mass at her left knee. There had been dull pain after long walking. There were no limitation of motion in physical examination. On plane lateral radiograph, radioopaque calcific densities were seen in elliptical soft tissue shadow below inferior pole of the patella. Magnetic resonance image demonstrated well defined mass of mixed signal intensity consistent with fat tissue and cartilaginous tissue. Gross specimen showed that the tumor appeared to be a round, encapsulated and firm nodule with milky whitish yellow cut surface. Microscopically the tumor consisted of nodular cartilage and mature fat tissue. The cartilage cells did not show mitotic figure and were often arranged in small clusters. But there were no cytologic features of malignancy. Thus the authors diagnosed this tumor as chondrolipoma, and report it with the literature review.