TumorsOutcome of Pelvic Bone Sarcomas in ChildrenLaitinen, Minna MD*,†; Parry, Michael FRCS*; Albergo, Jose I. MD*,‡; Jeys, Lee FRCS*; Sumathi, Vaiyapuri FRCPath§; Grimer, Robert FRCS*Author Information *Oncology Unit §Department of Musculoskeletal Pathology, Royal Orthopaedic Hospital NHS Foundation Trust, Birmingham, UK †Department of Orthopaedics, Unit of Musculoskeletal Surgery, Tampere University Hospital, Tampere, Finland ‡Hospital Italiano Buenos Aires, Buenos Aires, Argentina None of the authors received financial support for this study. The authors declare no conflicts of interest. Reprints: Minna Laitinen, MD, Department of Orthopaedics, Unit of Musculoskeletal Unit, Tampere University Hospital, P.O. Box 2000, Tampere 33521, Finland. E-mail: email@example.com. Journal of Pediatric Orthopaedics: November/December 2018 - Volume 38 - Issue 10 - p 537-542 doi: 10.1097/BPO.0000000000000860 Buy Metrics Abstract Background: Malignant bone tumors of the pelvis in children are rare and knowledge of their behavior is limited. Methods: A total of 113 skeletally immature patients under 16 years of age, comprising 58 females and 55 males were treated between 1983 and 2014. Tumors comprised Ewing’s sarcoma (ES) in 88 (77.9%) or osteosarcoma (OS) in 25 (22.1%). Metastases at diagnosis were present in 36 (31.9%). The mean follow-up was 5.2 years (2 to 16). Results: For patients with ES, the overall survival was 37.1% at 5-years and 33.5% at 10-years and 31.7% at 5- and 10-years in patients with OS. Local recurrence occurred in 24 patients with ES (27.3%) and 7 patients with OS (43.7%). Chemotherapy response was a predictor of local recurrence in ES with the lowest incidence seen in those with a good response to chemotherapy treated with a combination of radiotherapy and surgery. In patients with OS, both surgical margin and chemotherapy response influenced local control. Conclusions: Attaining a wide surgical margin should be the aim of treatment for all children with primary bone tumors of the pelvis. In ES, chemotherapy response has a greater influence on disease free and overall survival. Patients who demonstrate a poor response to chemotherapy should be considered for subsequent radiotherapy. Effort should be directed toward identifying nonhistologic methods of assessing chemotherapy response. Level of Evidence: Level IV—retrospective case study. Copyright © 2016 Wolters Kluwer Health, Inc. All rights reserved.