Fujiwara, Yu

Abstract Background Immune-related adverse events disrupt immune checkpoint inhibitor therapy and impact quality of life. Peripheral edema is common among patients with cancer, however the causality of peripheral edema can be unclear in the context of multidrug regimens. Methods PubMed/MEDLINE, Embase, and Web of Science were searched to identify phase 3 randomized controlled trials (RCTs) evaluating immune checkpoint inhibitors reporting peripheral edema incidence. The incidence of edema was calculated according to adverse event, immune checkpoint inhibitor, and treatment patterns. A random-effects meta-analysis pooled odds ratios (ORs) of edema incidence between immune checkpoint inhibitor and non–immune checkpoint inhibitor groups. A systematic review characterizing the interventions for immune-related peripheral edema was also conducted. Results From 58 RCTs (22 590 patients), treatment-related peripheral edema (grade 1-5) occurred in 2.80% (n = 195 of 6969) of patients receiving immune checkpoint inhibitor monotherapy, 4.96% (n = 112 of 2257) of patients receiving immune checkpoint inhibitor with chemotherapy, and 8.73% (n = 205 of 2349) of patients receiving immune checkpoint inhibitor with targeted therapy. Meta-analysis showed immune checkpoint inhibitor monotherapy had lower treatment-related peripheral edema incidence compared with chemotherapy (OR = 0.45, 95% CI = 0.27 to 0.73; P = .001, I2 = 69%) with the lowest relative incidence among programmed cell death protein 1 vs chemotherapy (OR = 0.41, 95% CI = 0.23 to 0.73; P = .003) and immune checkpoint inhibitor vs taxane chemotherapy (OR = 0.32, 95% CI = 0.18 to 0.58; P < .001). A systematic review of treatment outcomes for immune-related peripheral edema among 40 patients (19 studies) revealed 82.5% (n = 33 of 40) of cases received glucocorticoid treatment, and immune checkpoint inhibitors were permanently discontinued in 35% (n = 14 of 40). Conclusions Peripheral edema is a rare but potentially serious adverse event associated with immune checkpoint inhibitors. Immune checkpoint inhibitors likely confer less peripheral edema risk than taxane therapy. To avoid unnecessary treatment interruptions, treatment discontinuation requires careful consideration, particularly when edema develops following immune checkpoint inhibitor combination therapy.

11127 Background: Immune-related adverse events (irAEs) often require treatment discontinuation in patients with cancer receiving immune checkpoint inhibitors (ICIs). Given limited subsequent treatment options, ICI rechallenge is frequently considered. We aimed to estimate the incidence of recurrent irAEs and objective response rates (ORR) in patients receiving ICI rechallenge following prior irAEs. Methods: PubMed, Web of Science, and Embase were searched for studies evaluating ICI rechallenge in patients with advanced solid tumors who previously suspended treatment due to irAEs. Outcomes included the incidence of grade 1-5 (Gr1-5), Gr1-2, and Gr3-5 irAEs, recurrent irAEs, new irAEs, ORR, and disease control rate (DCR). Random-effects meta-analyses and subgroup analyses by cancer type were performed. Meta-regression analysis was conducted to evaluate the impact of the grade and type of initial irAEs on response outcomes. Heterogeneity was assessed using I 2 statistics (≥50% considered high). Results: Thirty-seven studies comprising 1,126 patients with initial irAEs (Gr1-2: 62.8%, Gr3-4: 37.2%) leading to suspension of ICIs were included. The most common initial irAEs in the pooled cohort were hepatitis/liver enzyme elevations (20.5%), pneumonitis (16.1%), and nephritis/acute kidney injury (14.8%). Pooled incidences of Gr1-5, Gr1-2, and Gr3-5 irAEs after ICI rechallenge were 42.2% (95% confidence interval [CI]: 35.3-49.3), 27.1% (95% CI: 22.9-31.7), and 18.8% (95% CI: 14.7-23.8), respectively. Subgroup analysis showed overall higher incidences of irAEs in melanoma (Gr1-5: 54.6%, Gr1-2: 23.2%, Gr3-5: 26.4%) than those in lung cancer (Gr1-5: 39.7%, Gr1-2: 27.4%, Gr3-5: 14.0%) and solid tumors (Gr1-5: 36.7%, Gr1-2: 22.8%, Gr3-5: 20.1%). The same type of irAEs recurred in 23.8% (95% CI: 20.1-28.0) of patients, while new types of irAEs developed in 29.3% (95% CI: 25.2-33.7) of patients undergoing ICI rechallenge. The overall ORR was 45.2% (95% CI: 34.5-56.4), with cancer type-specific ORRs of 60.5% (95% CI: 47.9-71.9) in melanoma, 39.1% (95% CI: 17.4-66.2) in lung cancer, and 39.5% (95% CI: 27.7-52.6) from studies investigating solid tumors. DCR was high across cancer types: 77.3% (95% CI: 67.7-84.7) overall, 68.2% (95% CI: 41.3-86.8) in melanoma, 91.2% (95% CI: 67.7-98.1) in lung cancer, and 72.5% (95% CI: 63.3-80.1) in solid tumors. Meta-regression analysis showed that commonly observed initial irAE types or grades of initial irAEs (Gr1-2 vs. Gr3-4) did not significantly impact ORR or DCR. Conclusions: ICI rechallenge after discontinuation due to irAEs demonstrates clinical activity but carries a substantial risk of both recurrent and new irAEs. These findings highlight the need for predictive biomarkers to optimize patient selection and maximize survival without compromising safety.

e14601 Background: Immune checkpoint inhibitors (ICIs) provide a long-term survival benefit across multiple cancer types, however immune-related adverse events (irAEs) occasionally disrupt treatments and impact quality of life. Peripheral edema from ICIs can occur due to increased peripheral vascular permeability. Thus, we aimed to evaluate the incidence and outcomes of ICI-related peripheral edema. Methods: MEDLINE, Embase, and Web of Science were searched to identify phase 3 randomized controlled trials (RCTs) reporting peripheral edema events in patients treated with ICIs. Incidence rates of peripheral edema were analyzed based on treatment patterns (monotherapy/combination therapy) and ICI subtypes (PD-1/PD-L1/CTLA-4). A random effect model meta-analysis was utilized to calculate pooled odds ratios of edema incidence between treatment groups. Finally, a systematic review was conducted to summarize treatment outcomes of peripheral edema associated with ICIs. Results: Overall, 58 RCTs comprising 22,590 patients were identified for the incidence analysis. Peripheral edema as treatment-related adverse events (TRAE) (Grade 1-5) occurred in 2.80% of patients receiving ICI monotherapy (n = 195/6969; PD-1 inhibitors: 2.22% [n = 104/4694], PD-L1: 3.73% [n = 58/1557], CTLA-4: 4.60% [n = 33/718]), 4.96% (n = 112/2257) of patients receiving ICI with chemotherapy, and 8.73% (n = 205/2349) of patients receiving ICI with molecular-targeted therapy. Grade 3-5 TRAE peripheral edema occurred in 0.19% (n = 13/6969) of patients treated with ICI monotherapy. Meta-analysis showed ICI monotherapy had lower TRAE peripheral edema compared to chemotherapy (OR = 0.45, 95% CI [0.27, 0.73], p = 0.001). Subgroup analysis based on ICI subtypes showed high heterogeneity in subgroups (p , I 2 = 87.1%), but PD-1 inhibitors were associated with lower incidence than chemotherapy (OR = 0.41, 95% CI [0.23, 0.73], ). Subgroup analysis of chemotherapy regimens revealed that taxane chemotherapy was associated with a higher incidence of TRAE peripheral edema than ICI monotherapy (OR = 0.32, 95% CI [0.18, 0.58], p = < 0.001), but the edema incidence was comparable between ICI monotherapy and non-taxane chemotherapy (OR = 1.05, 95% CI [0.53, 2.08], p = 0.13). A systematic review of irAE peripheral edema treatment outcomes identified 19 studies comprising 40 patients. In total, 82.5% (n = 33/40) of cases received glucocorticoid treatment, with 55.0% (n = 22/40) requiring a high dose (≥ 1 mg/kg/day) of prednisone. ICI was discontinued in 77.5% of patients (n = 31/40) due to peripheral edema with permanent discontinuation in 35% (n = 14/40). Conclusions: Peripheral edema is an occasional but clinically significant side effect of ICI therapy. Management of irAE edema can result in permanent ICI discontinuation, which has implications for cancer treatment outcomes.