Prophylactic cranial irradiation in patients with inoperable carcinoma of the lung. Preliminary report of a cooperative trial

Abstract

In March 1975, the Veterans Administration Lung Cancer Group (VALG) initiated a study of whole brain irradiation for subclinical metastases in patients with inoperable or unresectable carcinoma of the lung still confined to the thorax. Patients (all with negative brain scans) are stratified by institution and performance status, then randomly assigned such that half receive 2000 rad in 2 weeks to the entire brain with supervoltage irradiation. A second objective of the study is to evaluate short course local irradiation (4200 rad in 3 weeks) versus the more standard intermediate course (5000 rad in 5 weeks). With 341 patients entered in the study, preliminary results confirm that local control of disease with either dose‐time regimen is highly correlated with survival (p = .001). Tumor control with the short course regimen seems equivalent to the intermediate course (NSD is the same by design), but morbidity from the short course may be somewhat greater. Patients with small cell carcinoma have a higher rate of intracranial failure and the prophylactic dose used does not seem to control micrometastases in the brain. Prophylactic brain irradiation, even with low doses, does decrease the appearance of brain metastases in patients with squamous, large cell, and adenocarcinoma (p = .054). Longer observation will determine whether this is delay of appearance or actual control of brain metastases. Copyright © 1978 American Cancer Society