(P 272) THE HAZARDS OF BIOPSY IN PEDIATRIC SOFT TISSUE SARCOMAS

Objective: Pediatric soft tissue sarcomas (STS) are encountered by many surgical specialties. Deviations from oncologic principles alters patient outlook, as shown for all ages in the classic 1982 and 1996 studies by Mankin, Simon, and the Musculoskeletal Tumor Society (MSTS) membership. A similar review specific to pediatric tumors is lacking.

Methods: We retrospectively identified 114 patients < 18 years of age treated for STS or neoplasms of uncertain behavior (NUB, as defined by the WHO) of the trunk and extremities between 2010-2024. Each case was reviewed by a panel of four fellowship trained orthopedic oncologists and one pediatric general surgeon using a standardized questionnaire (Fig.1).

Results: 67 STS and 47 NUB were identified. 30% (20/67) of pediatric STS underwent an unplanned excision. STS that underwent unplanned excision were smaller than those undergoing planned excision or biopsy (p < 0.0001, Fig. 2). 13% (9/67) of patients with STS had a materially altered outlook due to biopsy or pathologic inaccuracy. 45% (21/47) of NUB had an unplanned resection. 10% (5/47) of NUB patients had an altered outlook. There was no difference in size of unplanned and planned excisions of neoplasms of uncertain behavior.

Conclusion: Pediatric soft tissue masses are treated by a variety of subspecialists. Unplanned resections of pediatric soft tissue sarcomas and neoplasm of uncertain behavior is not infrequent and leads to morbidity. Unplanned excisions of soft tissue sarcomas are more commonly performed in small tumors in pediatric patients. Increased understanding of pediatric soft tissue masses is needed to decrease the incidence of unplanned excision.

Figure 1