Risk factors for local recurrences after limb-salvage surgery for high-grade osteosarcoma of the extremities

Background. Improvements in preoperative staging as well as in chemotherapeutic regimens have made limb-salvage surgery a reliable modality of treatment for high-grade osteosarcomas of the extremities, with local recurrences in most series of less than 10% after this type of surgery. The quality of surgical margins and local response to preoperative chemotherapy are known to be the most significant factors in recurrence [1, 8-10, 12], and complications related to the biopsy procedure may also be a significant factor. The study reported here comprised a histopathological analysis of our recurrent cases as part of an effort to identify the impact of each of the factors cited above. Materials and methods. Five hundred fourteen cases of high-grade, non-multicentric osteosarcoma of the extremities were treated at the Istituto Ortopedico Rizzoli between March 1983 and August 1991. In this study we analyzed 23 cases of local recurrence in patients with classic osteosarcoma who underwent limb-salvage procedures. Results. In 15 cases we found correlation between the site of local recurrence and the site where the margins were less than wide. In five cases the recurrence was secondary to complications of the biopsy procedure (hematoma, delayed healing). In one case we suspect a previously undetected skip lesion. In the remaining two cases no clear explanation was found for the recurrence. There was also a statistically significant difference in the time of appearance of recurrences related to the tumor response to chemotherapy. Conclusions: For only two cases of recurrence was there no clear explanation. In one we suspect an undetected skip metastasis, and in the other there were certain factors which may have increased its risk of recurrrence (non diagnostic trochar biopsy followed by an incisional biopsy, fair tumor necrosis, recurrence in a 'problem' anatomical site, i.e., the popliteal space). In the remaining cases the following factors were found to be directly related to the development of a local recurrence: a) the quality of the surgical margins, b) site of the biopsy as well as complications related to the biopsy procedure, c) local response to preoperative chemotherapy.