Pediatric and Adult Patients Have Similar Functional Improvement After Endoprosthetic Reconstruction of Lower-Extremity Tumors.

Background: Although the treatment of lower-extremity bone tumors is similar between adult and pediatric patients, differences in outcomes are unknown. Outcomes for lower-extremity oncologic reconstruction have been challenging to study because of the low incidence and heterogeneity in disease and patient characteristics. The PARITY (Prophylactic Antibiotic Regimens in Tumor Surgery) trial is the largest prospective data set assembled to date for patients with lower-extremity bone tumors and presents an opportunity to investigate differences in outcomes between these groups.

Methods: Patient details were acquired from the prospectively collected PARITY trial database. The 1993 Musculoskeletal Tumor Society (MSTS-93) and Toronto Extremity Salvage Score (TESS) questionnaires were administered preoperatively and at 3, 6, and 12 months postoperatively. Continuous outcomes were compared between groups with use of the Student t test, and dichotomous outcomes were compared with use of the Pearson chi-square test.

Results: A total of 150 pediatric and 447 adult patients were included. Pediatric patients were more likely than adult patients to have a primary bone tumor (146 of 150 compared with 287 of 447, respectively; p < 0.001) and to have received adjuvant chemotherapy (140 of 149 compared with 195 of 441, respectively; p < 0.001). Reoperation rates were not significantly different between age groups (45 of 105 pediatric patients compared with 106 of 341 adult patients; p ≤ 0.13). Pediatric patients had higher mean MSTS-93 scores (64.7 compared with 53.8 among adult patients; p < 0.001) and TESS (73.4 compared with 60.4 among adult patients; p < 0.001) at baseline, which continued to 1 year postoperatively (mean MSTS-93 score, 82.0 compared with 76.8 among adult patients; p = 0.02; mean TESS, 87.7 compared with 78.6 among adult patients; p < 0.001). Despite the differences in outcomes between cohorts, pediatric and adult patients demonstrated similar improvement in MSTS-93 scores (mean difference, 17.4 and 20.0, respectively; p = 0.48) and TESS (mean difference, 14.1 and 14.7, respectively; p = 0.83) from baseline to 1 year postoperatively.

Conclusions: Pediatric patients had significantly better functional outcomes than adult patients at nearly all of the included postoperative time points; however, pediatric and adult patients showed similar mean improvement in these outcomes at 1 year postoperatively. These findings may be utilized to help guide the postoperative expectations of patients undergoing oncologic reconstruction.

Level Of Evidence: Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.