2019 Volume 45 Issue 12 Pages 659-666
Immune checkpoint inhibitors (ICIs) play an important role in oncology, as they generate novel toxicities known as immune-related adverse events (irAE) which affect multiple organ systems. Since irAEs have been reported to have potential clinical benefits for patients, retreatment using ICIs following recovery from irAEs is sometimes attempted, though there are limited data about the safety of using this strategy on patients with a serious irAE history. Here, the safety of retreatment after irAE across patients with different cancer types was evaluated. Fifty-three patients experienced treatment interruption because of irAEs; of these, 31 patients were then retreated with ICIs. Endocrine disorder as the initial irAE was observed more often in patients who were retreated; conversely, pneumonitis was observed more often in patients who were not retreated with ICIs. Manageable flare-up or novel irAEs occurred in 19 patients, while irAEs did not occur after retreatment in 12 patients. The number of days from the beginning of ICI treatment to the first irAE (within 100 days) as well as patient gender were found to be risk factors that were significantly related to relapses or new onsets of irAE. In 19 patients who experienced flare-up or new irAEs, the secondary irAE grade increase did not differ significantly compared to that of the initial irAE. The results of this study are important in helping to evaluate the risk of retreating patients with ICIs.
