2021 年 47 巻 5 号 p. 239-249
Adequate caution against immune related adverse events (irAE) is required for patients using immune checkpoint inhibitors. A relationship between tumor proportion score (TPS) and therapeutic outcomes has been reported; however, there are few reports on the relationship between TPS and the onset of irAE. This multicenter study retrospectively investigated the incidence of irAE with respect to TPS in patients treated with pembrolizumab monotherapy for unresectable recurrent non-small-cell lung cancer. The subjects included patients who started and completed pembrolizumab treatment between March 2017 and December 2019 at Hiroshima City Hiroshima Citizens Hospital, Hiroshima City Asa Citizens Hospital, and Iwakuni Clinical Center. We retrospectively investigated the onset of irAE, TPS expression, and patient background using electronic medical records. The patients (n = 104) were divided into two groups based on TPS expression: 1 - 49％ in Group A (n = 28) and 50 - 100％ in Group B (n = 76). irAE occurred in 10 patients (35.7％) in Group A and 45 patients (59.2％) in Group B, showing a significantly higher incidence in Group B. The median numbers of days until the initial onset of an irAE were 49.5 days in Group A and 35.0 days in Group B, showing a significantly shorter period in Group B. Therefore, when pembrolizumab monotherapy is administered in patients with unresectable recurrent non-small-cell lung cancer, maintaining safe treatment and appropriate management is crucial because irAE may have a higher incidence and appear early in patients with higher TPS (≧50％).
