Postirradiation sarcomas. A single-institution study and review of the literature

With improvement in survival after cancer treatment, it is becoming increasingly important to examine treatment-related morbidity and mortality. Sarcomas can develop in the irradiated field after radiation therapy (RT). The authors undertook a study to estimate the risk, and compared the risk of postirradiation sarcoma (PIS) with other treatment modalities used against cancer.

Since 1987 the authors have reviewed the records of 1089 patients with head and neck, gynecologic, gastrointestinal, and extremity sarcomas. Of these 1089 patients, 37 had a prior history of RT.

Conditions for which these patients received RT included: Hodgkin's disease (2 patients), retinoblastoma (3), non-Hodgkin's lymphoma (2), acne (1), astrocytoma (1), multiple recurrent mixed parotid tumor (1), laryngeal cancer (1), papillary adenocarcinoma of the thyroid (1), bony fibrous dysplasia (1), lymphangioma (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 doses ranged from 3000 to 12,440 cGy. Latency time from RT to the development of PIS averaged 12 years. More than 15,000 patients have received RT for various conditions at our institution since 1955.

From our data and a review of the literature, we estimate the risk of PIS with long-term follow-up to be 0.03-0.8%. From a review of the literature that compared mortality risks of chemotherapy, general surgery, and anesthesia, the risk of PIS appears no worse. Thus, given the large number of patients who can be cured or receive palliative treatment with RT, concern regarding PIS should not be a major factor influencing treatment decisions in patients with cancer.