POSTIRRADIATION SARCOMAS - A SINGLE-INSTITUTION STUDY AND REVIEW OF THE LITERATURE

Background. With improvement in survival after cancer treatment, it is becoming increasingly important to examine treatment-related morbidit y and mortality. Sarcomas can develop in the irradiated field after ra diation therapy (RT). The authors undertook a study to estimate the ri sk, and compared the risk of postirradiation sarcoma (PIS) with other treatment modalities used against cancer. Methods. Since 1987 the auth ors have reviewed the records of 1089 patients with head and neck, gyn ecologic, gastrointestinal, and extremity sarcomas. Of these 1089 pati ents, 37 had a prior history of RT. Results. Conditions for which thes e patients received RT included: Hodgkin's disease (2 patients), retin oblastoma (3), non-Hodgkin's lymphoma (2), acne (1), astrocytoma (1), multiple recurrent mixed parotid tumor (1), laryngeal cancer (1), papi llary adenocarcinoma of the thyroid (1), bony fibrous dysplasia (1), l ymphangioma (1), squamous cell carcinoma of the nasopharynx (1), Ewing 's sarcoma (1), choriocarcinoma (1), menorrhagia (4), cervical cancer (6), ovarian cancer (2), breast cancer (7), and hypoplasia (1). RT dos es ranged from 3000 to 12,440 cGy. Latency time from RT to the develop ment of PIS averaged 12 years. More than 15,000 patients have received RT for various conditions at our institution since 1955. Conclusions. From our data and a review of the literature, we estimate the risk of PIS with long-term followup to be 0.03-0.8%. From a review of the lit erature that compared mortality risks of chemotherapy, general surgery , and anesthesia, the risk of PIS appears no worse. Thus, given the la rge number of patients who can be cured or receive palliative treatmen t with RT, concern regarding PIS should not be a major factor influenc ing treatment decisions in patients with cancer.