Interstitial brachytherapy for pediatric soft tissue sarcoma: Evolving practice over three decades and long-term outcomes

Pediatr Blood Cancer. 2018 Sep;65(9):e27112. doi: 10.1002/pbc.27112. Epub 2018 May 10.

Abstract

Purpose: Evaluate long-term clinical outcomes, adverse effects, and evolving practice of interstitial brachytherapy (BT) for pediatric soft tissue sarcomas (STS).

Methods: From September 1984 to December 2014, 105 children (median age 10 years) were included. There were 60 males and 45 females. The majority (74%) had primary lesions. Synovial sarcoma (22%) was the most frequent histology. Treatment included wide local excision and BT with or without external beam radiotherapy (EBRT). Eighty-five (81%) received BT alone.

Results: After a median follow-up of 65 months, local control (LC), disease-free survival (DFS), and overall survival (OS) at 10 years were 83, 66, and 73%, respectively. On univariate analysis, LC was superior with tumors <5 cm versus >5 cm (93% vs. 75%, P = 0.10), Grade I/II versus Grade III tumors (97% vs. 73%, P = 0.01), nonround cell versus round cell histology (89% vs. 72%, P = 0.03), and trunk/extremity versus head and neck/genitourinary sites (87% vs. 57%, P = 0.0001). On multivariate analysis tumor size (P = 0.03) and location (P = 0.002) retained significance. Children receiving BT alone had comparable LC to those receiving BT and EBRT (84% vs. 80%, P = 0.43). There was no difference in LC between LDR versus HDR BT (86% vs. 83%, P = 0.30). Wound complications were seen in 6%. Subcutaneous fibrosis (25%), limb edema (6%), skeletal abnormalities (3%), and neuropathy (1%) were the late complications. One child (0.9%) developed a second malignancy after 7 years.

Conclusion: Interstitial BT with or without EBRT results in excellent outcomes. Radical BT alone, when used judiciously, results in excellent local control and function with minimal treatment-related morbidity.

Keywords: brachytherapy; outcomes; pediatric; soft tissue sarcoma.

MeSH terms

  • Adolescent
  • Antineoplastic Combined Chemotherapy Protocols / therapeutic use
  • Brachytherapy* / adverse effects
  • Brachytherapy* / methods
  • Child
  • Child, Preschool
  • Combined Modality Therapy
  • Disease-Free Survival
  • Extremities
  • Female
  • Follow-Up Studies
  • Head and Neck Neoplasms / drug therapy
  • Head and Neck Neoplasms / radiotherapy
  • Head and Neck Neoplasms / surgery
  • Humans
  • Infant
  • Kaplan-Meier Estimate
  • Male
  • Medical Oncology / trends
  • Radiotherapy, Adjuvant
  • Retrospective Studies
  • Sarcoma / drug therapy
  • Sarcoma / radiotherapy*
  • Sarcoma / surgery
  • Treatment Outcome
  • Urogenital Neoplasms / drug therapy
  • Urogenital Neoplasms / radiotherapy
  • Urogenital Neoplasms / surgery
  • Young Adult