Lung Stereotactic Body Radiation Therapy and Concurrent Immunotherapy: A Multicenter Safety and Toxicity Analysis

• Type of Material: Article
• Authors: Sibo Tian, Emory University; Jeffrey Switchenko, Emory University; Zachary Buchwald, Emory University; Pretesh Patel, Emory University; Joseph Shelton, Emory University; Shannon Kahn, Emory University; Rathi Pillai, Emory University; Conor Steuer, Emory University; Taofeek Owonikoko, Emory University; Madhusmita Behera, Emory University; Walter Curran Jr, Emory University; Kristin Higgins, Emory University
• Language: English
• Date: 2020-09-01
• Publisher: ELSEVIER SCIENCE INC
• Publication Version: Author Accepted Manuscript (After Peer Review)
• Copyright Statement: 2020
• License: Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International
• Final Published Version (URL): http://dx.doi.org/10.1016/j.ijrobp.2019.12.030
• Title of Journal or Parent Work: INTERNATIONAL JOURNAL OF RADIATION ONCOLOGY BIOLOGY PHYSICS
• Volume: 108
• Issue: 1
• Start Page: 304
• End Page: 313
• Keywords: Oncology; CLINICAL ACTIVITY; RADIOTHERAPY; PHASE-1; Science & Technology; CANCER-IMMUNOTHERAPY; PEMBROLIZUMAB; OPEN-LABEL; PNEUMONITIS; Radiology, Nuclear Medicine & Medical Imaging; DEATH 1; NIVOLUMAB; Life Sciences & Biomedicine; INHIBITORS
• Research Categories: Health Sciences, Radiology; Health Sciences, Oncology

Abstract

Purpose: Radical treatment of metastases with stereotactic body radiation therapy (SBRT) is commonly implemented in patients receiving concurrent immune checkpoint inhibition (ICI), despite limited safety and toxicity data. The purpose of this study was to evaluate the safety and tolerability of lung SBRT with concurrent ICI. Methods and Materials: Records from a single academic institution were reviewed to identify patients treated with lung SBRT and concurrent (within 30 days) ICI; a contemporaneous cohort receiving lung SBRT alone was included for reference. Treatment-related adverse effects occurring within 30 days (acute) and 180 days (subacute) of SBRT were evaluated. Results: Our study included 117 patients; 54 received SBRT with concurrent ICI (56 courses, 69 target lesions), and 63 received SBRT alone (68 courses, 79 lesions). Median follow-up was 9.2 months in the SBRT + ICI cohort. Among the patients, 67.9% received ICI monotherapy, 17.9% ICI/chemotherapy, and 14.3% ICI/ICI combinations; 25% received ICI between SBRT fractions, and 42.9% received ICI both before and after SBRT. The risk of grade 3 pneumonitis was higher in the SBRT + ICI versus SBRT alone cohort (10.7% vs 0%, P <.01) and any-grade pneumonitis was similar (33.9% vs 27.9%, SBRT + ICI vs SBRT, P =.47). The risk of any-grade pneumonitis appeared elevated with ICI/ICI combinations (62.5% vs 29.2%). Receipt of ICI, planning treatment volume, and lobes involved in SBRT were linked to high-grade pneumonitis. Subacute grade 3+ adverse effects occurred in 26.8% of SBRT + ICI and 2.9% of SBRT-alone patients. Conclusions: Overall, concurrent lung SBRT + ICI is safe. Given the clinically meaningful risk of pneumonitis, closer monitoring should be considered for SBRT + ICI patients, especially those receiving radiation therapy with ICI/ICI combinations.