POSTOPERATIVE RADIATION FOR LUNG-CANCER METASTATIC TO THE BRAIN

Purpose: Although resection of single brain metastases and postoperati ve whole-brain radiation therapy (WBRT) improves survival, compared wi th treatment using WBRT alone, the value of postoperative WBRT after r esection of brain metastases is controversial. We analyzed the largest reported series of lung cancer patients with resected brain metastase s to evaluate the impact of postoperative WBRT. Materials and Methods: Between 1974 and 1989, 185 patients with non-small cell lung cancer ( NSCLC) underwent resection of brain metastases. Patients who had recei ved preoperative WBRT (23%, 42 of 185) were excluded. The remaining pa tients were divided into group A (no WBRT; n = 32), group B (patients received WBRT and were prognostically matched to group A; n = 32), and group C (all other WBRT patients; n = 79). Most patients received pos toperative doses of 30 Gy in 10 fractions. Higher doses were used in 1 6% of group B and 18% of group C patients. Results: Overall 5-year sur vival rates were as follows: group A, 12%; B, 8%; C, 16%. Overall brai n failures occurred in 38% of patients in group A, 47% in group B, and 42% in group C. The use of WBRT (group A v groups B plus C) had no ap parent impact on survival or on overall brain failure rates. In partic ular, no improvement in either of these parameters could be demonstrat ed when group B was compared with group A. Focal failure (defined as f ailure within the brain adjacent to the site of the resected brain met astases) occurred as follows: group A, 34% (11 of 32); groups B plus C , 23% (25 of 111) (P = .07). WBRT significantly reduced focal failure for patients with adenocarcinoma (group A, 33% [eight of 24]; groups B plus C, 14% [11 of 79]; (P = .05). Nonfocal failure (anatomically dis tinct from the resected metastasis) occurred in 9% of patients in grou p A (three of 32), 21% in groups B plus C (23 of 111) (P = .07). Concl usion: Long-term survival is possible when NSCLC brain metastases are resected. postoperative WBRT (as used in this series only had an impac t on the focal control of brain metastases and this effect was of bord erline significance, The lack of conclusive benefit supports the need for ongoing randomized trials to test the value of adjuvant postoperat ive WBRT. Brain failures were relatively common in all three groups of patients, which suggests that doses greeter than 30 Gy need to be stu died. (C) 1994 by American Society of Clinical Oncology.