Lung Toxicity in Non-Small-Cell Lung Cancer Patients Exposed to ALK Inhibitors: Report of a Peculiar Case and Systematic Review of the Literature

Lung toxicity is a potential fatal effect involving non-small-cell lung cancer (NSCLC) patients exposed to tyrosine kinase inhibitors (TKIs). Moving from our experience regarding a patient who developed lung toxicity while receiving 2 different anaplastic lymphoma kinase (ALK)-TKIs, we performed a systematic review to assess the epidemiologic magnitude and the clinical significance of such toxicity in NSCLC patients treated with ALK-TKIs. Studies were identified using MEDLINE and additional sources (European Society for Medical Oncology, American Society of Clinical Oncology, and World Conference on Lung Cancer abstracts) in agreement with Preferred Reporting Items for Systematic Reviews and Meta-Analyses and Cochrane guidelines. Lung toxicity was reported in 105 of 4943 NSCLC patients (2.1%). Crizotinib was responsible for pulmonary adverse events (AEs) in 1.8% of exposed patients (49 of 2706). With the limit of a lower number of treated patients (n = 359), brigatinib resulted as the most frequently involved in lung toxicity (7%; n = 25). Pulmonary AEs during therapy with ceritinib, alectinib, and lorlatinib occurred in 1.1%, 2.6%, and 1.8% of the patients, respectively. Sixty-five percent of cases accounted for Grade 3 or 4 events, with a mortality rate of 9%. Radiological patterns of pneumonia were reported in 25 patients, whereas imaging evocative of interstitial lung disease in 37. Overall, 26 of 105 patients (25%) permanently discontinued treatment because of lung toxicity. Lung toxicity is a rare albeit potentially severe side effect in NSCLC patients receiving ALK-TKIs, apparently more frequent with brigatinib. Its early recognition and treatment are crucial for the best outcome of this subgroup of patients, whose overall prognosis is being improved by the availability of several targeted agents.