The safety evaluation of biopsy in malignant bone tumors

Abstract

Objective To investigate the incidence and extent of biopsy tract contamination in malignant bone tumors by either core needle biopsy or open biopsy and detect the safe extent in resection of biopsy tract. Methods Forty-eight cases were performed core needle biopsy, including 37 osteosarcomas, 5 malignant fibrous histiocytomas, 1 juxtacortical osteosarcoma, 1 low grade central osteosarcoma, 1 periosteal osteosarcoma, 1 primary malignant melanoma of bone and 2 chondrosarcomas. There were 37 males and 11 females with a mean age of 23.3 years (range, 10-64 years). The mean time between core needle biopsy and definitive surgery was 1.3 months (range, 0-2 months). All the patients were performed limb salvage surgery.Twenty-six cases were performed open biopsy, including 20 osteosareomas, 1 Ewing's sarcoma, 2 chondrosarcomas, 1 mesenchymal chondrosarcoma, 1 malignant fibrous histiocytoma, 1 lymphoma. There were 21males and 5 females with a mean age of 21.9 years (range, 8-59 years). The mean time between open biopsy and definitive surgery was 2.3 months (range, 1-4 months). The tumor and tissue around the biopsy tract at least 2 cm were resected. The pathological examination was performed in specimens via the biopsy tract, including the normal soft tissue outside the tumor, deep fascia, subcutaneous tissue and skin. The incidence and extent of biopsy tract contamination were evaluated with pathological examination. Results Forty-four cases were followed up. The mean follow-up time was 17.6 months (range, 4-39 months). In core needle biopsy group, four of forty-eight cases were found malignant tumor cells seeding in biopsy tract, the positive rate was 8.3%. In open biopsy group, all the cases were followed up with the mean time of 12.9 months (range, 2-29 months), and two of twenty-six cases were found malignant tumor cells seeding in biopsy tract,the positive rate was 7.7%. Conclusion Biopsy of malignant bone tumors has the risk of biopsy tract contamination. The tumor cell seeding exists in both core needle biopsy and open biopsy. The biopsy tract should be performed en bloc resection with the tumor. Key words: Bone Neoplasms; Biopsy; Neoplasm seeding; Neoplasm recurrence, local