2023 Volume 41 Issue 1 Pages 36-44
Pembrolizumab for patients with advanced or recurrent solid tumors with high frequency microsatellite instability (MSI-High) that has worsened after cancer chemotherapy has been covered by health insurance since December 2018 in Japan. In this study, 9 of 13 patients with uterine endometrial cancer treated with pembrolizumab achieved a response, and they all maintained a long response of more than 6 months. Five of the nine responders had immune-related adverse events (irAEs). Two patients had serious irAEs that required pembrolizumab discontinuation, but both were appropriately treated, and the patients survived without recurrence for a long period after discontinuation. In addition, three patients with Grade 1 or 2 irAEs resumed treatment and have maintained long-term recurrence-free responses since then. Pembrolizumab tends to have a high response rate and a relatively long period of response, and is considered a useful treatment that can be continued while maintaining the patient's quality of life (QOL). However, severe irAE can significantly impair the quality of life, thus the careful observation of clinical symptoms and laboratory data during treatment and the establishment of a system that allows simple cooperation with specialist departments in the event of an irAE are essential.
