The role of radiation therapy in the treatment of small cell lung cancer.

Patients with small cell lung cancer (SCLC) are candidates for aggressive therapy because of their potential for long-term survival, especially patients with limited-stage disease. Although no treatment protocol can be considered "standard", the best results in limited-stage SCLC appear to be produced by a combination of chemotherapy and thoracic irradiation. Ongoing protocols testing the efficacy of thoracic irradiation should be able to settle question of the optimal treatment approach in limited-stage SCLC over the next 1 to 2 years. Careful attention to volume treated and the use of shrinking fields produce the best results with the minimum of toxicity. Treatment of extensive-stage SCLC has not been substantially improved to date with the addition of local or systemic irradiation. Prophylactic cranial irradiation reduces the incidence of CNS failure in SCLC and should be given, at a minimum, to patients achieving complete response status. Whether patients with partial response should also receive prophylactic cranial irradiation remains controversial. Finally, half-body radiation in SCLC is an experimental research technique that has shown some promise but remains quite toxic when combined with systemic chemotherapy.