Latent Sarcomatous Consequences of Therapeutic Irradiation in Long-Term Brain Tumor Survivors: A Paradigm of Iatrogenic Complexity

Introduction

Radiation therapy is an essential component of cancer treatment and has substantially improved survival for patients with many primary brain tumors. However, exposure to ionizing radiation can, rarely, result in the development of secondary malignancies years after treatment. Radiation-induced sarcoma (RIS) represents an uncommon but clinically important late complication of radiotherapy and has been described as an iatrogenic consequence of successful cancer treatment. RIS accounts for approximately 3% of all soft-tissue sarcomas and has been reported in approximately 0.03%–0.3% of patients exposed to therapeutic radiation. Reported 5-year overall survival remains poor, ranging from approximately 10% to 36%. Beyond its clinical significance, RIS illustrates the temporal complexity of therapeutic risk, in which a treatment that provides substantial immediate benefit may contribute to a rare adverse outcome many years later.