Programmed cell death 1 (PD-1) inhibitor-related diarrhea is increased due to the rising administration of PD-1 inhibitor across different tumor types. This adverse event is potentially life-threatening, thus requiring appropriate management. However, its incidence among various tumor types is barely known yet.
Thirty-three original articles of PD-1 inhibitor monotherapy trials were identified based on a PubMed search completed on October 6, 2017. The incidences of all-grade and grade ≥3 diarrhea were collected.
Thirty-three studies containing 7322 patients were included in the meta-analysis. The overall incidence of diarrhea during PD-1 inhibitor monotherapy was 11.3% (95% CI, 9.7%-12.9%) for all-grade and 0.8% (95% CI, 0.6%-1.1%) for grade ≥3 diarrhea. The incidence was higher in renal cell carcinoma (RCC) for both all-grade (14.4% vs 9.4%) and grade ≥3 diarrhea (1.3% vs 0.7%) compared with non-small-cell lung cancer (NSCLC) but only for all-grade diarrhea (14.4% vs 8.5%) compared with urothelial carcinoma. The incidence in melanoma was higher than in NSCLC (15.7% vs 9.4%) and urothelial carcinoma (15.7% vs 8.5%) for all-grade diarrhea but not for grade ≥3 diarrhea. No significant differences were noted between Nivolumab and Pembrolizumab for allgrade diarrhea (11.7% vs 10.7%) or grade ≥3 diarrhea (0.9% vs 0.8%).
The incidence of PD-1 inhibitor-related diarrhea was higher in RCC and melanoma. There was no significant difference in PD-1 inhibitor-related diarrhea between two types of PD-1 inhibitors. These results contribute to heighten clinicians’ awareness of potential adverse events in diverse tumor types.
Clinical trial identification
Legal entity responsible for the study
Radiation Oncology, Chongqing Cancer Institute & Chongqing Cancer Hospital & Chongqing Cancer Center & Chongqing University Cancer Hospital, Chongqing, CN.
Has not received any funding.
All authors have declared no conflicts of interest.