Radiological Findings of Bizarre Parosteal Osteochondromatous Proliferation

PURPOSE: To analyse the radiological findings of bizarre parosteal osteochondromatous proliferation (BPOP), a rare benign tumorous lesion with a high frequency of recurrence which frequently occurs around the short tubular bones of the hands and feet. MATERIALS AND METHODS: Between 1984 and 1998, 19 cases of BPOP were pathologically Proven, and in is of these, six men and nine women aged between 17 and 69(mean, 41) years, plain radiographs were available for analysis. We examined the location and size of lesions, and their relationship to adjacent bone. RESULTS: In all cases, trabecular bone formations were present. There were not separable from adjacent bones, which in all cases appeared normal. In nine of 15 cases margins were sharp, and in the remaining six they were irregular. Lesions were located around a phalanx of the hand (n=5), a metatarsal bone (n=3), a long bone (n=3), a phalanx of the foot (n=2), a metacarpal bone (n=1), and a metatarsophalangeal joint (n=1). Their average size was 2.5 x1.9cm, and in three of is cases the tumor recurred. CONCLUSIONS: BPOP showed a well-marginated mass of heterotopic mineral arising around short tubular bones. These findings were useful for diagnosis and differential diagnosis.