PCI for NSCLC

The RTOG 0214 reports out in the JCO this week: This was a randomized trial looking at PCI in NSCLC for stage III NSCLC. Unfortunately the trial closed after 356 accrued; their goal was just over 1,000, and the trial was not going to achieve it's objectives. The survival rates at 1year were identical, even with a very significant reduction in the amount of brain metastases (HR 2.5). Of course, one could say that the trial simply didn't have the power to detect the difference, but even with ~350 patients, one would like to at least see a signal of benefit, which was lacking in at least the current analysis.

Looking at the rates of brain mets in the control arm 18%, one must wonder if we could better select those that are likely to develop mets in the future, and run a trial in an enriched cohort with a higher likelihood of disease. This is were I think the future of PCI for NSCLC lies.

In a companion piece, the QOL portion was reported. Not surprisingly there were primarily deteriorations seen in memory and recall - without significant decreases in overall function or global QOL. Nonetheless - this underlines the importance of selecting a group more likely to benefit, in light of known risks.

Link and Abstract from the JCO:

Phase III Comparison of Prophylactic Cranial Irradiation Versus Observation in Patients With Locally Advanced Non-Small-Cell Lung Cancer: Primary Analysis of Radiation Therapy Oncology Group Study RTOG 0214 [Thoracic Oncology]: "Purpose

This study was conducted to determine if prophylactic cranial irradiation (PCI) improves survival in locally advanced non–small-cell lung cancer (LA-NSCLC).

Patients and Methods

Patients with stage III NSCLC without disease progression after treatment with surgery and/or radiation therapy (RT) with or without chemotherapy were eligible. Participants were stratified by stage (IIIA v IIIB), histology (nonsquamous v squamous), and therapy (surgery v none) and were randomly assigned to PCI or observation. PCI was delivered to 30 Gy in 15 fractions. The primary end point of the study was overall survival (OS). Secondary end points were disease-free survival (DFS), neurocognitive function (NCF), and quality of life. Kaplan-Meier and log-rank analyses were used for OS and DFS. The incidence of brain metastasis (BM) was evaluated with the logistic regression model.

Results

Overall, 356 patients were accrued of the targeted 1,058. The study was closed early because of slow accrual; 340 of the 356 patients were eligible. The 1-year OS (P = .86; 75.6% v 76.9% for PCI v observation) and 1-year DFS (P = .11; 56.4% v 51.2% for PCI v observation) were not significantly different. The hazard ratio for observation versus PCI was 1.03 (95% CI, 0.77 to 1.36). The 1-year rates of BM were significantly different (P = .004; 7.7% v 18.0% for PCI v observation). Patients in the observation arm were 2.52 times more likely to develop BM than those in the PCI arm (unadjusted odds ratio, 2.52; 95% CI, 1.32 to 4.80).

Conclusion

In patients with stage III disease without progression of disease after therapy, PCI decreased the rate of BM but did not improve OS or DFS.

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