TUMOR CONTAMINATION IN THE BIOPSY PATH OF PRIMARY MALIGNANT BONE TUMORS

Objective: To study factors possibly associated with tumor contamination in the biopsy path of primary malignant bone tumors. Method: Thirty-five patients who underwent surgical treatment with diagnoses of osteosarcoma, Ewing's tumor and chondrosarcoma were studied retrospectively. The sample was analyzed to characterize the biopsy technique used, histological type of the tumor, neoadjuvant chemotherapy used, local recurrences and tumor contamination in the biopsy path. Results: Among the 35 patients studied, four cases of contamination occurred (11.43%): one from osteosarcoma, two from Ewing's tumor and one from chondrosarcoma. There was no association between the type of tumor and presence of tumor contamination in the biopsy path (p = 0.65). There was also no association between the presence of tumor contamination and the biopsy technique (p = 0.06). On the other hand, there were associations between the presence of tumor contamination and local recurrence (p = 0.01) and between tumor contamination and absence of neoadjuvant chemotherapy (p = 0.02). Conclusion: Tumor contamination in the biopsy path of primary malignant bone tumors was associated with local recurrence. On the other hand, the histological type of the tumor and the type of biopsy did not have an influence on tumor contamination. Neoadjuvant chemotherapy had a protective effect against this complication. Despite these findings, tumor contamination is a complication that should always be taken into consideration, and removal of the biopsy path is recommended in tumor resection surgery.