CLINICO-PATHOLOGICAL REVIEW OF PELVIC OSTEOCHONDROMAS

Abstract

Aim: The pelvis is a rare location for osteochondromas and differentiation from chondrosarcomas can be difficult. We aim to aid this differentiation using tends and demographics of treated cases.

Methods and Results: Patients referred to a supra-regional bone tumour centre with pelvic tumours, consequently diagnosed as osteochondromas were studied to determine the clinico-pathological features that differentiate them from chondrosarcoma. Treatment outcome was also reviewed.

30 patients were studied with a mean follow-up of 32 months. The mean age at diagnosis was 34yrs (range 19–79). The male to female ratio was 1:1. The most common location was the ilium (19 patients), with the pubis and ischium accounting for a third of patients. Only 1 patient had an acetabular osteochondroma. Median duration of symptoms prior to referral was 6 months (1–79). Pain without a lump was the main presenting symptom (16 patients), followed by lump with pain (6), and lump alone (6). Two patients presented with obstructive labour requiring emergency procedures. The lesions were solitary in 24 and associated with hereditary multiple exostosis (HME) in 6 patients. 1 patient had a radiation induced lesion.

The lesions showed increased uptake on bone scans and the cartilage cap was less than 10mm in all but 2 patients. Treatment was surgical excision in 21 patients and observation with serial radiographs in 9. Histological examination confirmed osteochondroma in all patients, however 1 patient with HME had areas of Grade I malignancy. Significant surgical complications occurred in 1 patient who developed pulmonary embolism.

Conclusion: We conclude that symptoms from osteochondromas of the pelvis are similar to those with chondrosarcomas and increased uptake on bone scans is seen in both. However, a tumour with a cartilage cap larger than 10mm or arising from the acetabulum is unlikely to be an osteochondroma.