Pneumatosis intestinalis in cancer patients who received immune checkpoint inhibitors

Pneumatosis Intestinalis, Pneumoperitoneum, Pneumoretroperitoneum, Pneumomediastinum, and Pneumobilia After Pembrolizumab Therapy: A Case Report

“…Together, the time to PI onset after initiating pembrolizumab and an increase in suspected pembrolizumab-induced PI cases [ 4 - 7 ] support pembrolizumab as the most likely catalyst here. Sperling et al found that in patients who developed suspected cases of ICI-induced PI, the median time to onset after initiating the drug was seven months and occurred within one year of the most recent dose [ 5 ]. The onset from initiation and most recent dose in our case closely aligns with the findings from Sperling et al [ 5 ], seeing that our patient presented approximately six months after starting pembrolizumab and two months after her most recent dose.…”

“…Sperling et al found that in patients who developed suspected cases of ICI-induced PI, the median time to onset after initiating the drug was seven months and occurred within one year of the most recent dose [ 5 ]. The onset from initiation and most recent dose in our case closely aligns with the findings from Sperling et al [ 5 ], seeing that our patient presented approximately six months after starting pembrolizumab and two months after her most recent dose. A delay in adverse effects of ICIs seen here and in other studies may be explained by several hypothesized mechanisms, including a latent or subclinical autoimmune state induced by ICIs [ 8 ].…”

“…Regarding the patient's CT finding of pneumoperitoneum with PI, pneumoperitoneum appears to be a common finding in patients with ICI-induced PI. Sperling et al found that pneumoperitoneum was present in 50% of patients with ICI-induced PI [ 5 ]. In the current case, the pneumoperitoneum was likely secondary to massive ICI-induced PI, given the lack of perforation at surgery.…”

“…Other cases of PI associated with ICI therapy have been successfully managed with conservative treatment [ 5 - 6 ]. Khalil et al previously developed an algorithm for determining whether emergent surgery, re-assessment, or a conservative approach would be indicated in patients with PI [ 16 ].…”

“…Identifying a medication as the causative factor is essential considering the recurrence rate, potential delay in presentation, and overall high mortality rate associated with PI. More recently, immune checkpoint inhibitors (ICIs), an emerging class of anticancer drugs typically reserved for treating resistant cancer, have been associated with PI rarely [5]. There are limited studies regarding the implication of pembrolizumab, a programmed cell death protein 1 (PD-1) inhibitor, in developing PI [4][5][6][7].…”