Prophylactic cranial irradiation (PCI) versus observation in radically treated stage III non-small cell lung cancer (NSCLC): A randomized phase III NVALT11 study.

Abstract

8502 Background: Brain metastases are one of the major sites of tumor failure in patients (pts) with radically treated stage III NSCLC. The value of PCI in these pts remains unsettled. This study is designed to investigate whether PCI reduces the incidence of symptomatic brain metastases (sBM). Methods: Pts were randomized between observation and PCI after concurrent or sequential chemo-RT with or without surgery. PCI dose was left to the physician(36 Gy/18F, 30 Gy/12F, 30 Gy/10F). Pts were registered before randomization, those progressing after chemo-RT were not randomized. Pts were followed for sBM (defined as increased intracranial pressure, headache, nausea, vomiting, cognitive, affective disturbances, seizures, focal neurological symptoms andMRI/CT), side effects, survival, quality of life (QLQ-C30, EuroQol 5D). The primary endpoint is the proportion of patients developing sBM. Randomizing 300 pts the study has 90% (2-sided p = 0.05) power to detect 17% decrease in pts developing sBM at 24 months (mo). Results: Between 2009 and 2015, 195 pts were registered, 175 were randomized, 87 received PCI and 88 pts were in the observation arm. In 2013 due to slow accrual, it was decided to reduce the number of randomized pts to 175 pts. With 75 events a 2-sided log-rank test would have 80% power to detect HR 0.52 and alpha 0.05. One pt in PCI arm was withdrawn after randomization. Pts characteristics were male (n = 114, 66%); adeno/squa/other 72 (41%), 62 (36%), 40 (23%); PS 0/1/2 66 (38%), 99 (57%), 9 (5%); stage IIIA/B 93 (53%), 80 (46%), unknown 1 (1%). Median follow up was 48.5 mo (95% CI, 39 - 54). Proportion of pts with sBM was 4/86 (4.6%) in PCI and 25/88 (28.4 %) in observation (p < 0.00001). Seven (8.1%) pts in PCI and 26 (29.7%) pts in observation arm had BM on imaging (p < 0.001). Median time to sBM was not reached in either arm. Median OS was 24.2 mo in PCI and 21.9 mo in observation arm (p = 0.52). Global QoL at 3 mo was worse in PCI arm (p = 0.02) but not afterwards. Conclusions: PCI significantly decreases the proportion of patients developing both symptomatic BM without influencing overall survival. PCI decreases 3 months global quality of life measures but not beyond. Clinical trial information: NTR 1601.