Risk of Death from Pneumocystis jirovecii after Curative-intent Radiotherapy for Lung Cancer

Abstract

Background Radical radiotherapy is given in the curative setting for patients with non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC). Pneumocystis jirovecii pneumonia (PJP) in HIV-negative patients carries a high mortality. We determined the risk of death from PJP in a cohort of patients treated with radical radiotherapy. Methods Case records for all patients treated with radical radiotherapy for NSCLC and SCLC in Northern Ireland, between Jan 2011 and Dec 2016 inclusive, were examined to determine the cause of death. Survival was estimated using the Kaplan Meier method. Results 683 patients were studied. At a median follow up of 15 months, 379 patients (55%) had died. The cause of death was determined in all but 5 patients. 6 patients died with progressive pneumonia and quantitative PCR confirmation of PJP infection. A further 8 patients died of progressive pneumonia with bilateral radiological changes. Whilst no serological or microbiological confirmation was available they met the criteria for possible PJP infection. All patients had received corticosteroids within the preceding 3 months; 13 had lymphopenia for at least a month prior to diagnosis. The actuarial risk of death from definite or possible PJP was 2.6% at 2 years (95% CI 1.2% to 4.0%). Conclusions We conclude that there is a clinically significant risk of death from PJP in patients treated with radiotherapy. An association with prior steroid use and prolonged lymphopenia is noted. We advocate the use of chemoprophylaxis in patients receiving steroids who have had radical radiotherapy.