Radiation recall pneumonitis triggered by an immune checkpoint inhibitor following re-irradiation in a lung cancer patient: a case report

Xianghua Ye,Jinsong Yang ,Justin Stebbing,Ling Peng

doi:10.1186/s12890-022-01846-x

Abstract

BackgroundRadiation recall pneumonitis (RRP) is unpredictable but associated with severe radiation damage in previously irradiated fields. Chemotherapy and targeted drugs have been reported to contribute to RRP. Here we report a case of a patient with non-small cell lung cancer (NSCLC) who developed RRP following administration of immune checkpoint inhibitor (ICI) 18 months after the end of re-irradiation.Case presentationA 69-year-old man received adjuvant chemoradiotherapy post-operatively. He underwent thoracic re-irradiation for oligometastatic NSCLC. On second recurrence, pembrolizumab combined with nab-paclitaxel were administered. After six months, he developed symptoms of persistent cough and dyspnea, with consistent pneumonitis on CT images. The clinical time frame and significant radiographic evidence raised suspicion for RRP. Symptoms resolved after steroids.ConclusionsRRP is a rare occurrence. Patients undergoing immunotherapy after prior irradiation may be at increased risk of this rare radiation pneumonitis.

Highlights

Radiation recall pneumonitis (RRP) is unpredictable but associated with severe radiation damage in previously irradiated fields
Patients undergoing immunotherapy after prior irradiation may be at increased risk of this rare radiation pneumonitis
In a phase III randomized trial investigating durvalumab after concurrent chemoradiotherapy (CCRT) in stage III non-small cell lung cancer (NSCLC), the pneumonitis rate was reported as 34%, compared to 25% in placebo arm [8]

Summary

Introduction

Radiation recall pneumonitis (RRP) is unpredictable but associated with severe radiation damage in previously irradiated fields. Patients undergoing immunotherapy after prior irradiation may be at increased risk of this rare radiation pneumonitis. The differential diagnosis between radiation pneumonitis and checkpoint inhibitor-induced pneumonitis (CIP) is of importance for patients receiving both treatments.

Results

Conclusion