Immune checkpoint inhibitors (ICIs) can cause myenteric plexopathy, which could result in delayed gastric emptying (GE) and possibly gastroparesis. We assessed the clinical outcomes of patients who had pre-existing gastroparesis or who developed symptoms of delayed GE following ICI therapy. We retrospectively identified adults with ICD-9 and ICD-10 codes for gastroparesis who received ICI therapy between 1 January 2020 and 31 December 2022 at a tertiary cancer center. Of 76 eligible patients, 37 had pre-existing gastroparesis; 39 (0.2% of the more than 18,000 screened) developed symptoms of delayed GE after ICI therapy, of which 27 (69%) patients had an alternative etiology for delayed GE. Four patients (11%) with pre-existing gastroparesis had a flare-up after ICI, and the median time to flare-up was 10.2 months (IQR, 0.7–28.6 months); for patients with new onset of suspected delayed GE after ICI, the median time to symptom onset was 12.8 months (IQR, 4.4–35.5 months). The clinical symptom duration of patients without an alternative etiology (74.5 days (IQR, 21.5–690 days)) and those with an alternative etiology (290 days (IQR, 147–387 days)) did not differ significantly (p = 1.00). Delayed GE after ICI therapy is a rare presentation but has a late onset and a prolonged symptom duration.

Objectives: Immune-mediated colitis (IMC) is a common immune-related adverse event during immune checkpoint inhibitor (ICI) therapy. This case series and review aimed to highlight atypical cases of IMC and explore the potential of PET/CT to predict imminent ICI colitis. Methods: Through a descriptive, retrospective study at a tertiary cancer center, we identified adult patients receiving ICIs for any cancer between 2010 and 2022 who also underwent PET/CT for routine cancer surveillance during this time. We included patients who had signs and symptoms of colitis and reviewed their surveillance PET/CT scans obtained 2 to 6 weeks before and up to 3 months after diagnosis. Results: For the 33 included patients, surveillance scans were reviewed in collaboration with a nuclear radiologist. A total of 17 patients (51.5%) received combination therapy, while 14 (42.4%) received anti–PD-1/PD-L1 monotherapy. While ICI therapy has a median duration of 6.5 months, most patients (72.7%) had negative surveillance PET/CT for colitis. Diarrhea and colitis severity were similar among those with positive and negative findings for colitis on surveillance PET/CT. The outcomes of colitis were similar, with an 81.8% resolution in patients with negative PET/CT and 71.4% in patients with positive PET/CT. Conclusions: PET/CT imaging did not appear to assist in predicting IMC. This may be due to the long interval between clinical IMC and surveillance PET/CT imaging. The continued use of clinical criteria combined with laboratory markers, e.g., lactoferrin and calprotectin, and endoscopy/histology will enable more accurate detection and timely treatment of IMC.

Background: Gastrointestinal (GI) infections, which often result in or stem from intestinal dysbiosis, can affect the efficacy of immune checkpoint inhibitors (ICIs) and increase the risk of adverse effects, such as colitis. In this study, we explored the impact of GI infections before initiation of ICI therapy on the incidence and severity of immune‐mediated colitis (IMC) and survival. Methods: A single‐center, retrospective review including all patients who received ICIs from January 2010 to February 2024 and subsequently developed IMC. Patients were screened for IMC and prior GI infections based on symptoms and stool tests. Patients' demographic, IMC, and GI infection–related clinical data were collected. Results: Thirty‐four of the 1132 patients (3.0%) included in the analysis had GI infections before ICI therapy. GI infections were most commonly caused by Clostridioides difficile and most often treated with oral antibiotics (interquartile range [IQR], 7–14 days). The incidence of IMC was higher in patients with prior GI infections compared to patients without prior infections (8.7% vs. 5.1%, p = 0.002). IMC symptoms, severity, and outcomes were similar in both groups ( p > 0.05). In multivariate Cox proportional survival analysis, prior GI infection was independently associated with an increased risk of mortality (odds ratio, 1.6 [95% CI, 1.4–1.8]; p < 0.001) for patients who received ICIs. Conclusions: Our study is the first to explore the impact of GI infection before ICI therapy on IMC risk and survival. We found that prior GI infection was associated with an increased incidence of IMC and an increased risk of mortality in patients receiving ICIs.

Background: The diagnosis of autoimmune pancreatitis (AIP) can be challenging due to nonspecific symptoms, low sensitivity of serologic markers, and some overlap in presentation with pancreatic ductal adenocarcinoma (PDAC). We aimed to quantify delays in the diagnosis of AIP and identify factors associated with diagnostic delay. Methods: This was a single-center retrospective study between 2013 and 2023 of adult patients diagnosed with type 1 AIP based on HISORt criteria. Patients were compared to a randomly selected group of controls with PDAC. Data on clinical presentation, lab results, imaging, procedures, and initial treatment regimen were collected. Timing to diagnosis and predictive factors were identified and compared between groups. Results: Overall, 41 patients with AIP were identified and compared to 41 patients with PDAC. AIP patients had delays in diagnosis from symptom onset compared to controls (79.1±141.2 vs. 5.2±5.43 weeks, P<0.001). Within the AIP group, female sex (136.6±202.2 vs. 42.3±63.5 weeks, P=0.004) and fatty infiltration of the pancreas on imaging (194.1±163.9 vs. 33.7±60.3 weeks, P<0.001) were associated with delays in diagnosis, respectively. Presenting with jaundice (27.1±33.0 vs. 93.7±156.3 weeks, P=0.01) and obtaining endoscopic ultrasound-guided or surgical biopsies (49.7±79.9 vs. 221.6±262.9 weeks, P=0.04) were associated with a shorter time from symptom onset to diagnosis, respectively. Patients were more promptly diagnosed in the last 5 years of the study compared to the first 5 years (13 vs. 28 weeks, P=0.02). Conclusions: AIP remains a challenging diagnosis, with extensive delays in diagnosis averaging 1.5 years from symptom onset. Our findings may improve patient identification and reduce diagnostic delay in AIP patients.