Prophylactic Cranial Irradiation for Limited-Stage Small-Cell Lung Cancer Patients: Secondary Findings From the Prospective Randomized Phase 3 CONVERT Trial.

Abstract

INTRODUCTION:

The impact of the dose and fractionation of thoracic radiotherapy on the risk of developing brain metastasis (BM) has not been evaluated prospectively in limited stage SCLC patients receiving prophylactic cerebral irradiation (PCI).

METHODS:

Data from patients treated with PCI from the CONVERT trial were analyzed.

RESULTS:

Four hundred forty-nine of 547 patients (82%) received PCI after completion of chemoradiotherapy. Baseline brain imaging consisted of computed tomographic scans in 356 of 449 patients (79%) and magnetic resonance imaging in 83 of 449 (18%) patients. PCI was delivered to 220 of 273 participants (81%) in the twice-daily (BD) group and 229 of 270 in the once-daily (OD) group (85%; p = 0.49). Total median PCI dose was 25 Gy in both the BD and OD groups (p = 0.74). In patients who received PCI, 75 (17%) developed BM (35 [8%] in OD and 40 [9%] in BD) and 173 (39%) other extracranial progression. In the univariate analysis, gross tumor volume (GTV) was associated with an increased risk of BM (p = 0.007) or other radiological progression events (p = 0.006), whereas in a multivariate analysis both thoracic GTV (tGTV) and ECOG performance score were associated with either progression type. The median overall survival (OS) of patients treated with PCI was 29 months. In the univariate analysis of OS, PCI timing from end of chemotherapy, weight loss of more than 10%, and tGTV were prognostic factors associated with OS. In the multivariate analysis, only tGTV was associated with OS. Delay between end of chemotherapy and PCI was not associated with OS.

CONCLUSIONS:

Patients receiving OD or BD thoracic radiotherapy have the same risk of developing BM. Larger tumors are associated with a higher risk of BM.

• Authors: Antonin Levy, Cécile Le Péchoux, Hitesh Mistry, Isabelle Martel-Lafay, Andrea Bezjak, Delphine Lerouge, Laetitia Padovani, Paul Taylor, Corinne Faivre-Finn
• Journal: Journal of thoracic oncology : official publication of the International Association for the Study of Lung Cancer (J Thorac Oncol) Vol. 14 Issue 2 Pg. 294-297 (02 2019) ISSN: 1556-1380 [Electronic] United States
• PMID: 30292850 (Publication Type: Clinical Trial, Phase III, Journal Article, Multicenter Study, Randomized Controlled Trial, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2018 International Association for the Study of Lung Cancer. Published by Elsevier Inc. All rights reserved.

Topics

• Brain Neoplasms (diagnostic imaging, prevention & control, radiotherapy, secondary)
• Chemoradiotherapy
• Cranial Irradiation
• Disease Progression
• Dose Fractionation, Radiation
• Humans
• Lung Neoplasms (pathology, therapy)
• Magnetic Resonance Imaging
• Neoplasm Staging
• Prospective Studies
• Severity of Illness Index
• Small Cell Lung Carcinoma (radiotherapy, secondary, therapy)
• Survival Rate
• Tomography, X-Ray Computed
• Tumor Burden