Purpose: To analyze 20 cases of postradiation sarcoma (PRS) to determine dose levels at which this condition developed, the pathology of the initial and postradiation tumors, latency period, and outcome; and to review the literature and propose modified criteria for diagnosis.
Methods and materials: Patient records were reviewed. Previous radiation fields and isodose charts were reconstructed to determine the dose received in the tissue in which the PRS subsequently developed.
Results: There were 16 female patients and 4 male patients. Mean age at the time of initial radiotherapy was 28 years. Mean latency was 14 years, with no difference in latency between the adult and pediatric group (t = 0.45, p = 0.37), but shorter latency in the retinoblastoma than in the nonretinoblastoma patients (t = 3.18, p = 0.003). The outcome was poor; 2 patients were alive and disease-free at 2 and 5 years. The 18 patients who died as a result of PRS had a median survival of 1 year.
Conclusion: PRSs are rare. Unnecessary radiation must be avoided. Cases should be reported with full details so that risk factors can be ascertained. PRSs usually arise in moderate to higher dose areas. Diagnostic criteria should allow soft tissue tumors and short latency.