TAPO in first-line osimertinib therapy and continuation of osimertinib.

BACKGROUND: Osimertinib is associated with a relatively high frequency of drug-induced interstitial lung disease (D-ILD), and transient asymptomatic pulmonary opacities (TAPO) have been reported to occur during osimertinib administration. The frequency of TAPO during first-line treatment and the pros and cons of osimertinib continuation is unknown. METHODS: This was a multicenter, retrospective study. The purpose of this study was to research the frequency of TAPO and to evaluate osimertinib continuation in first-line therapy. We also evaluated progression-free survival (PFS) including subgroup analysis. RESULTS: From August 2018 to December 2020, 133 patients were enrolled into the study. The median observation period was 23.2 months (0.3-48.3 months). Thirty patients (22.6%) experienced D-ILD events, including 16 patients (12.1%) with CTCAE grade 1, five patients (3.8%) with grade 2, and nine patients (6.7%) with grade 3 and above D-ILD. Among the patients with grade 1 D-ILD, 11 cases (8.3%) of TAPO were observed, and all patients succeeded in osimertinib continuation. The TAPO images were characterized by localized patchy opacities (73%). The median PFS was 22.6 months (95% confidence interval [CI]: 17.8-28.7 months). Patients with TAPO had a significantly longer PFS than patients with non-TAPO D-ILD in the multivariate analysis. CONCLUSIONS: This study showed that grade 1 D-ILD might include TAPO and that patients with TAPO might have good PFS. We need to consider the possibility of osimertinib continuation when lung opacities appear.

Exacerbation of nontuberculous mycobacterial pulmonary disease in a patient with advanced non-small-cell lung cancer during treatment with PD-1 inhibitor and chemotherapy.

A 69-year-old man visited our hospital due to an abnormal shadow on a chest X-ray. Chest CT showed a mass shadow in his left lower lobe accompanied by an infiltrative shadow in the right upper lobe. Thorough examination led to a diagnosis of pulmonary squamous cell lung carcinoma, stage IIIB (T3N2M0). Combination treatment with chemotherapy and programmed cell death receptor 1 (PD-1) inhibitor was started, leading to a partial response. However, his pre-existing pulmonary infiltrative shadow progressed during the maintenance treatment with PD-1 inhibitor, and sputum culture revealed Mycobacterium abscessus infection. Thus, exacerbation of pre-existing nontuberculous mycobacterial pulmonary disease (NTM-PD) resulting from treatment with PD-1 inhibitor was suspected. Then, treatment with PD-1 inhibitor was discontinued, and he underwent pulmonary resection after antibiotic therapy against Mycobacterium abscessus infection. Recently, special attention has been paid to the association of Mycobacterium tuberculosis (TB) infection and treatment with immune checkpoint inhibitors (ICIs) in TB-endemic areas. This case also emphasizes the importance of realizing the risk of NTM infection when treating patients with ICIs, especially in NTM-endemic areas.