Phase II, multicenter study of plasminogen activator inhibitor-1 inhibitor (TM5614) plus nivolumab for treating anti-PD-1 antibody-refractory malignant melanoma: TM5614-MM trial.

BACKGROUND: Anti-programmed cell death 1 antibodies (anti-PD-1 Abs) are widely used for advanced melanoma, but the efficacy of an anti-PD-1 Abs is limited in the Asian population. There remains an unmet need to improve the therapeutic effects of anti-PD-1 Abs treatment, particularly in melanoma patients who are refractory to anti-PD-1 Abs. The aim was to evaluate anti-PD-1 Abs treatment in combination with TM5614 (plasminogen activator inhibitor-1: PAI-1 inhibitor) in patients with unresectable melanoma. METHODS: The TM5614-MM study was a multicentre, open-label, single-arm, phase 2 clinical trial to evaluate the efficacy and safety of nivolumab in combination with TM5614 in patients with advanced, unresectable malignant melanoma recruited at 7 Japanese institutes between 13 September 2021 and 31 March 2023. Patients with metastatic or unresectable melanoma previously treated with anti-PD-1 Abs were enrolled. Nivolumab 480 mg was administered intravenously every 4 weeks for 8 weeks, while TM5614 was administered orally at a dose of 120 mg (0-4 weeks) and 180 mg once daily (5-8 weeks). The primary endpoint was the overall response rate after 8 weeks of concomitant use of TM5614. RESULTS: Thirty nine patients were enrolled, and 34 patients in the anti-PD-1 Abs-refractory cohort. The overall response rate at 8 weeks was 25.9% (95% CI: 12.9-44.9%; P = .027) in 27 anti-PD-1-Abs refractory patients by investigator assessment in the protocol per set cohort. Seven patients discontinued treatment due to progressive disease or adverse events. Treatment-related grade 3 or higher adverse events occurred in 3 of 39 patients (7.7%) in the intention-to-treat cohort. CONCLUSIONS: TM5614 in combination with nivolumab is well-tolerated and effective in anti-PD-1 Abs-refractory, unresectable melanoma. TRIAL REGISTRATION: This trial was registered with Clinical Trial gov, jRCT2021210029.

Adverse events associated with postoperative outcomes of adjuvant anti-PD-1 antibody therapy in both acral and non-acral cutaneous melanomas: A multicenter, observational, post hoc analysis study.

Since anti-PD-1 Abs can cause irreversible immune-related adverse events (irAEs), the associations between their efficacies and the incidence of irAEs are important to evaluate the use of anti-PD-1Abs for the treatment of melanoma, especially in the adjuvant setting. The purpose of this post hoc analysis study was to retrospectively analyze the associations between recurrence-free survival (RFS) at 12 months and the onset of any irAEs in 31 non-acral cutaneous and 30 acral melanoma cases treated with anti-PD-1 Abs therapy at the adjuvant setting in Asians. There were 20 cases with greater than grade 1 AEs in both the acral and non-acral cutaneous groups. Of the acral melanoma, 10 cases were nails or toes, and 20 cases were soles and heels. The log-rank test showed that RFS was better in cases with AEs than in cases without AEs. The present study suggested that the different profiles of irAEs between non-acral cutaneous and acral melanoma might correlate with the different response to anti-PD1 Abs of melanoma in the adjuvant setting.

Efficacy and safety of TM5614 in combination with paclitaxel in the treatment of paclitaxel-resistant cutaneous angiosarcoma: Phase II study protocol.

Cutaneous angiosarcoma (CAS) is an endothelial cell-derived, highly aggressive type of vascular tumour. Although chemoradiotherapy with paclitaxel (PTX) is recognized as a first-line therapy for CAS, second-line therapy for CAS remains controversial, and there is no standard therapy for taxane-resistant CAS. Plasminogen activator inhibitor-1 (PAI-1) is associated with poor clinical outcomes, and elevated levels of PAI-1 in both tissue and serum are correlated with poor response to therapy in various cancers, including skin cancers. Since PAI-1 protects endothelial cells from Fas ligand-mediated apoptosis, PAI-1 inhibition might induce apoptosis of endothelial cell-derived tumours such as CAS. This is a single-arm, open-label, multi-institutional, Phase 2 clinical trial to assess the efficacy and safety of PTX in combination with TM5614 (PAI-1 inhibitor) in patients with PTX-resistant CAS. PTX will be administered for 28 weeks, with oral administration of TM5614. The primary endpoint of this study will be the overall response rate (ORR) at 28 weeks after starting treatment (central image evaluation). The secondary endpoint will include the ORR at 28 weeks after starting treatment (investigator evaluation), ORR at 8 weeks and 16 weeks after initiation of treatment (central and investigator evaluation), progression-free survival, overall survival, disease control rate and safety profiles. Assuming the null hypothesis of a response rate of 13.6% and an alternative hypothesis of 45%, a minimum of 15 patients are required to achieve a two-sided, Type I error of 5% and power of 70% based on the exact binomial distribution. Data quality control will be conducted by a combination of centralized (remote) and on-site monitoring. This study will contribute to the development of novel combination therapy for PTX-resistant CAS patients, which remains an unmet clinical need.

Systemic therapy for Asian patients with advanced BRAF V600-mutant melanoma in a real-world setting: A multi-center retrospective study in Japan (B-CHECK-RWD study).

BACKGROUND: Anti-PD-1-based immunotherapy is considered a preferred first-line treatment for advanced BRAF V600-mutant melanoma. However, a recent international multi-center study suggested that the efficacy of immunotherapy is poorer in Asian patients in the non-acral cutaneous subtype. We hypothesized that the optimal first-line treatment for Asian patients may be different. METHODS: We retrospectively collected data of Asian patients with advanced BRAF V600-mutant melanoma treated with first-line BRAF/MEK inhibitors (BRAF/MEKi), anti-PD-1 monotherapy (Anti-PD-1), and nivolumab plus ipilimumab (PD-1/CTLA-4) between 2016 and 2021 from 28 institutions in Japan. RESULTS: We identified 336 patients treated with BRAF/MEKi (n = 236), Anti-PD-1 (n = 64) and PD-1/CTLA-4 (n = 36). The median follow-up duration was 19.9 months for all patients and 28.6 months for the 184 pa tients who were alive at their last follow-up. For patients treated with BRAF/MEKi, anti-PD-1, PD-1/CTLA-4, the median ages at baseline were 62, 62, and 53 years (p = 0.03); objective response rates were 69%, 27%, and 28% (p < 0.001); median progression-free survival (PFS) was 14.7, 5.4, and 5.8 months (p = 0.003), and median overall survival (OS) was 34.6, 37.0 months, and not reached, respectively (p = 0.535). In multivariable analysis, hazard ratios (HRs) for PFS of Anti-PD-1 and PD-1/CTLA-4 compared with BRAF/MEKi were 2.30 (p < 0.001) and 1.38 (p = 0.147), and for OS, HRs were 1.37 (p = 0.111) and 0.56 (p = 0.075), respectively. In propensity-score matching, BRAF/MEKi showed a tendency for longer PFS and equivalent OS with PD-1/CTLA-4 (HRs for PD-1/CTLA-4 were 1.78 [p = 0.149]) and 1.03 [p = 0.953], respectively). For patients who received second-line treatment, BRAF/MEKi followed by PD-1/CTLA-4 showed poor survival outcomes. CONCLUSIONS: The superiority of PD-1/CTLA-4 over BRAF/MEKi appears modest in Asian patients. First-line BRAF/MEKi remains feasible, but it is difficult to salvage at progression. Ethnicity should be considered when selecting systemic therapies until personalized biomarkers are available in daily practice. Further studies are needed to establish the optimal treatment sequence for Asian patients.

Analyzing the relationship between the efficacy of first-line immune checkpoint inhibitors and cumulative sun damage in Japanese patients with advanced BRAF wild-type nonacral cutaneous melanoma: A retrospective real-world, multicenter study.

BACKGROUND: Efficacy of anti-PD-1 antibody monotherapy (PD1) or anti-PD-1 plus anti-CTLA-4 combination therapy (PD1 +CTLA4) for melanoma is affected by its clinical subtype. The amount of tumor mutation burden (TMB) caused by cumulative sun damage (CSD) is occasionally used to explain this; however, their relationship in Japanese nonacral cutaneous melanoma (NACM) is still unclear. OBJECTIVE: To analyze the ICI efficacy and its relationship with CSD of the primary lesion in Japanese patients with NACM. METHODS: Japanese patients with advanced BRAF wild-type NACM who received first-line ICIs were recruited. Objective response rate (ORR), progression-free survival (PFS), and overall survival (OS), and the degree of solar elastosis (SE) were evaluated. RESULTS: A total of 146 patients (PD1 group 113 and PD1 +CTLA4 group 33) were included. No significant differences in ORR were observed between the PD1 and PD1 +CTLA4 groups (35 % vs. 36 %; P = 0.67) or PFS and OS (median PFS 6.1 months vs. 8.5 months; P = 0.46, median OS 28.1 months vs. not reached; P = 0.59). Multivariate survival analysis revealed that PD1 +CTLA4 did not prolong the PFS and OS. The SE score had no effect on either PFS or OS. CONCLUSIONS: ICI efficacy was not as high as those reported in Western countries, and PD1 +CTLA4 did not present better clinical efficacy compared to PD1. Indicators of CSD did not serve as a predictor for clinical advantage. These findings may partially support the theory that ICI efficacy is affected by CSD; however, other unrecognized factors may also exist.

Treatment for taxane-resistant cutaneous angiosarcoma: A multicenter study of 50 Japanese cases.

Cutaneous angiosarcoma (CAS) is a rare and highly aggressive type of vascular tumor. Although chemoradiotherapy with taxanes is recognized as a first-line therapy for CAS, second-line therapy for CAS remains controversial. From the above findings, the efficacy and safety profiles of taxane-switch (change paclitaxel to docetaxel or vise), eribulin methylate, and pazopanib regimens in second-line chemotherapy were evaluated retrospectively in 50 Japanese taxane-resistant CAS patients. Although there was no significant difference in progression-free survival (P = 0.3528) among the regimens, the incidence of all adverse events (AEs) (P = 0.0386), as well as severe G3 or more AEs (P = 0.0477) was significantly higher in the eribulin methylate group and pazopanib group than in the taxane-switch group. The present data suggest that switching to another taxane should be considered for the treatment of taxane-resistant CAS in second-line therapy based on the safety profiles.

Cutaneous angiosarcoma treated with taxane-based chemoradiotherapy: A multicenter study of 90 Japanese cases.

Cutaneous angiosarcoma (CAS) is rare and most previous studies of CAS have been small case series, and randomized, phase II studies of CAS are limited. Since treatment options for CAS are controversial, and because only paclitaxel should be recommended based on high-level evidence, it is important to evaluate the efficacy of another taxane-derived agents, docetaxel, in real-world practice. The efficacy and safety profiles of chemoradiotherapy using taxane-based agents, docetaxel and paclitaxel, were retrospectively examined in the maintenance setting in 90 Japanese CAS patients, including 35 docetaxel-treated cases and 55 paclitaxel-treated cases. Overall survival and dose duration time of the patient group treated with docetaxel was equivalent to that with paclitaxel, even in the cohorts with metastasis. Adverse events due to docetaxel and paclitaxel were observed in 77.1% and 69.1% of cases, respectively. The incidence ratio of total severe adverse events tended to be higher in the docetaxel-treated group (40.0%) than in the paclitaxel-treated group (23.6%). Peripheral neuropathy occurred only in the paclitaxel-treated group, whereas high-grade interstitial pneumonia developed only in the docetaxel-treated group. In addition, we also evaluate 19 patients selected other taxanes, 17 patients selected eribulin methylate, 11 patients pazopanib, and 2 patients selected nivolumab as second-line chemotherapy. The efficacy of a monthly docetaxel regimen is equivalent to a three-weekly paclitaxel regimen evaluated by Overall survival and DDT, even in the cohorts with metastasis, and it is a tolerable protocol for CAS as a maintenance therapy in the Japanese population.

Sentinel lymph node biopsy in extramammary Paget disease: A 13-year institutional experience.

Whether sentinel lymph node biopsy status is a prognostic factor or effective in determining treatment strategies in extramammary Paget disease remains unclear. This study aimed to investigate the significance of sentinel lymph node biopsy in extramammary Paget disease. We retrospectively reviewed the clinical information of previously untreated patients with invasive extramammary Paget disease who underwent wide local excision of the primary tumor and sentinel lymph node biopsy at our hospital between April 2008 and March 2021. Clinical data including the baseline neutrophil-to-lymphocyte ratio and recurrence-free survival were analyzed. Sentinel lymph node metastases were classified as macrometastases and micrometastases, with a cut-off value for sentinel lymph node tumor burden of 2 mm. Univariate and multivariate analyses of factors affecting sentinel lymph node biopsy positivity and recurrence-free survival rates were performed. Overall, 85 patients were included in the analysis. Patients in the sentinel lymph node biopsy-positive group (n = 26) had a significantly higher invasion level and neutrophil-to-lymphocyte ratio. According to multivariate analyses, invasion level and a high neutrophil-to-lymphocyte ratio were independent predictive factors for sentinel lymph node biopsy positivity, and the sentinel lymph node biopsy status was an independent prognostic factor for recurrence-free survival. In conclusion, sentinel lymph node biopsy provides an accurate risk classification and clinical indication for postoperative follow-up in patients with invasive extramammary Paget disease.

Neutrophil-to-lymphocyte ratio is a potential prognostic biomarker for extramammary Paget disease: A retrospective study.

The neutrophil-to-lymphocyte ratio (NLR) is a useful prognostic biomarker for many cancer types. However, the prognostic value of NLR in patients with extramammary Paget disease (EMPD) remains unclear. This study aimed to determine whether NLR is associated with overall survival (OS) in patients with EMPD. In this single-center retrospective case series, we analyzed data of 109 patients with previously untreated EMPD who presented to our hospital. Data on age, sex, primary tumor site, invasion level, presence of lymph node and distant metastases, baseline NLR, and OS were analyzed. The enrolled patients were classified into the metastatic or non-metastatic EMPD groups. The metastatic EMPD group had higher invasion level and NLR value (p < 0.001 and p = 0.005, respectively) compared with the non-metastatic EMPD group. Cox proportional hazards model analysis showed invasion level (p = 0.0093) and NLR value (p = 0.019) to be independent prognostic factors for OS. Notably, multivariate analysis revealed that invasion level (p = 0.045) and NLR value (p = 0.036) were independent prognostic factors for OS in the metastatic EMPD group. The limitations of this study include the small number of participants and its retrospective nature. In conclusion, since NLR can be routinely assessed with high feasibility, it might be a useful biomarker for predicting prognosis in patients with EMPD.

Adjuvant Anti-PD-1 Antibody Therapy for Advanced Melanoma: A Multicentre Study of 78 Japanese Cases.

Anti-PD-1 antibodies (Abs) are among the optimal adjuvant therapies for melanoma at high risk of recurrence, especially BRAF wild-type melanoma, but the anti-tumour effects of anti-PD-1 Abs in the adjuvant setting for acral melanoma have not been evaluated previously. The aim of this study was to analyse the efficacy and safety profiles of anti-PD-1 Ab monotherapy in the adjuvant setting in an Asian population including a high ratio of acral melanoma. The efficacy and safety profiles of anti-PD-1 Ab monotherapy in the adjuvant setting were retrospectively analysed in 78 Japanese patients with advanced melanoma, including 31 cases (40%) of acral melanoma. Overall relapse-free survival was 60.3% (47 of 78 cases, 95% confidence interval (CI) 49.2-70.4%), and 39.7% of patients (31 of 78 patients, 95% CI 29.6-50.8%) relapsed during the adjuvant PD-1 Ab treatment. Six cases (7.9%) discontinued the protocol due to serious adverse events. One case (1.3%) discontinued the protocol due to trauma. The relapse-free survival of acral melanoma was 25.8%, whereas that of high cumulative sun damage was 60.0%, and that of low cumulative sun damage was 57.1%. The acral type had a significantly lower 12-month relapse-free survival than other cutaneous types (p = 0.029). The acral type appeared to be an independent prognostic factor on multivariate analysis (p = 0.015). Adverse events due to anti-PD-1 antibody were observed in 37.1% overall. The results of this study suggest that anti-PD-1 Ab therapy in the adjuvant setting is less effective for acral melanoma than for other cutaneous types.

Concordance in judgment of clinical borders of basal cell carcinomas in Japanese patients: A preliminary study of JCOG2005 (J-BASE-MARGIN).

Basal cell carcinoma is the most common type of skin cancer, and surgical excision with clear margins is the standard of care. Surgical margins are determined based on risk factors (high or low risk) for recurrence according to the National Comprehensive Cancer Network and Japanese basal cell carcinoma guidelines. The clarity of the clinical tumor border (well-defined or poorly defined) is considered a risk factor, and significant discrepancies in the judgment of clinical tumor borders among dermato-oncologists may occur. Therefore, we analyzed the dermato-oncologists' concordance in judging the clinical tumor border of basal cell carcinoma. Forty-seven dermato-oncologists (experts: 37; young trainees: 10) participated in this study. The datasets of clinical and dermoscopic photographs of 79 Japanese cases of head and neck basal cell carcinoma were used to determine the concordance in the judgment of clinical tumor border. The probability of the border that was selected more often was used to calculate the rater agreement rate for each dataset. Correct judgment was defined as a more frequently selected border, and the concordance rate of clarity of clinical tumor border for each dermato-oncologist was calculated based on the definition of the correct judgment. A median concordance rate of 85% or higher for all dermato-oncologists was predefined as an acceptable rate for clinical use. Of the 79 datasets, rater agreement rates were 80-100%, 60-79%, and 51-59% for 55, 19, and five datasets, respectively. The median concordance rate for all dermato-oncologists was 86% (interquartile range: 82-89%). There was no significant difference in the concordance rate between the experts and the trainees (median, 87% vs. 85.5%; p = 0.58). The concordance rates of dermato-oncologists for all datasets were relatively high and acceptable for clinical use.

Management of elderly patients with advanced cutaneous squamous cell carcinoma.

The incidence of cutaneous squamous cell carcinoma has been increasing rapidly in recent years, especially among the elderly. The purpose of this review article is to summarize the findings of studies on systemic therapy for advanced cutaneous squamous cell carcinoma, to review geriatric screening tools, which can assess frailty and predict treatment outcomes, and discuss the indications of their use in advanced cases. A literature review revealed that studies on systemic therapy for advanced cutaneous squamous cell carcinoma often included relatively older patients. However, there has been little research on the safety and efficacy of systemic therapy for advanced disease that takes older age and frailty into account. Notably, studies on geriatric screening for skin cancer have been conducted in recent years, mainly to detect early-stage resectable cases. The Geriatric 8 screening tool is considered the most useful for predicting post-operative complications in patients with early-stage cancer, as it can evaluate comorbidities, polypharmacy and cognition, has appropriate measurement properties, can be quickly executed and is clinically relevant, easily understandable and interpretable. This geriatric screening tool may also be applicable in advanced-stage cancer. In conclusion, despite the fact that advanced cutaneous squamous cell carcinoma occurs mainly in the elderly, the importance of geriatric screening has not yet been fully appreciated by dermato-oncologists. In the future, geriatric screening tools should be actively used in clinical trials for the appropriate assessment of drug efficacy and toxicity in elderly patients with advanced cutaneous squamous cell carcinoma.

Neutrophil-to-lymphocyte ratio is associated with survival and sentinel lymph node positivity in invasive cutaneous squamous cell carcinoma: A retrospective study.

BACKGROUND: The neutrophil-to-lymphocyte ratio (NLR) is a known prognostic biomarker for survival and is predictive of sentinel lymph node (SLN) positivity in some cancers. However, its usefulness as a prognostic biomarker for cutaneous squamous cell carcinoma (cSCC) has not been fully investigated. OBJECTIVE: Our objective was to investigate the relationship between the NLR and the disease-specific survival and SLN positivity in patients with cSCC. METHODS: In this single-center retrospective case series, we analyzed patients with cSCC who underwent blood tests prior to the initiation of treatment at our oncology hospital. The relationship between the patients' clinical characteristics (including the NLR) and the disease-specific survival and SLN positivity was evaluated using univariate and multivariate analyses. RESULTS: An elevated NLR was an independent prognostic factor for poor disease-specific survival and a predictive factor for SLN positivity. LIMITATIONS: Limitations include the small number of participants and selection bias due to the large proportion of high-risk cases in our patient population. CONCLUSION: NLR is a useful biomarker in cSCC because it is simple to measure and can predict prognosis.

Retrospective analysis of adjuvant therapy using dabrafenib plus trametinib in Japanese patients with advanced melanoma: analysis of 36 cases.

Patients with resected stage IIIB, IIIC and IIID melanomas have a high risk of recurrence. Therefore, an appropriate protocol for stage III melanoma is needed. Since adjuvant dabrafenib plus trametinib (D+T) combined therapy and anti-PD1 antibody (Ab) therapy reduce the risk of recurrence in patients with resected stage III BRAF-mutated melanoma, selecting the adjuvant therapy for BRAF-mutated melanoma is controversial. The efficacy and safety profiles of D+T combined therapy in the adjuvant setting were retrospectively analyzed in 36 Japanese. BRAF-mutated advanced melanoma patients. The relapse-free rate (RFR) at 12 months was 82.1% (95% confidential interval (CI), 63.9-92.6%). In the 21 patients who completed the protocol, the RFR at 12 months was 85.7% (95% CI, 64.5-95.9%). In the seven patients whose protocol was interrupted by adverse events, the RFR was 71.4% (95% CI, 35.2-92.4%). The incidence rate of any AEs for all patients was 69.7% (95% CI, 52.5-82.8%), including 13 cases of pyrexia, five cases of skin rash and four cases of liver dysfunction. The present study suggested that D+T therapy in the adjuvant setting is a useful and very tolerable protocol for BRAF-mutated melanoma in the Japanese population.

Association Between Serum Insulin-Like Growth Factor 1 Levels and the Clinical Symptoms of Chronic Schizophrenia: Preliminary Findings.

Purpose: Insulin-like growth factor 1 (IGF-1) is a trophic mediator that is regulated by growth hormone and associated with the proliferation, development, and growth of neural cells. IGF-1 may be associated with the pathophysiology of schizophrenia, but this association remains controversial. This study aimed to investigate the relationship between serum IGF-1 levels and psychiatric symptoms in patients with chronic schizophrenia. Patients and Methods: A total of 65 patients were recruited from the University of Occupational and Environmental Health, Komine Eto Hospital, Moji Matsugae Hospital, Shin-Moji Hospital, and Tsutsumi Hospital in Kitakyushu between September 2019 and June 2020. Further, 20 healthy age- and sex-matched control participants were recruited from the Komine Eto Hospital and the University of Occupational and Environmental Health. Patients with schizophrenia were assessed using the Positive and Negative Syndrome Scale (PANSS) and the Drug-Induced Extrapyramidal Symptoms Scale. Serum levels of free plus albumin-bound IGF-1 (IGF-1) were measured by immunoradiometric assay. The measurements were performed using antibody beads for bound/free separation. Associations between serum IGF-1 levels and the PANSS scores were determined. We also examined the associations between serum IGF-1 levels and diabetes, antipsychotic drug use, and disease duration. Results: No significant difference was found in the serum IGF-1 level between patients with schizophrenia and healthy controls. Serum IGF-1 levels were significantly negatively correlated with the PANSS total score (R 2 = 0.06, p = 0.015) and PANSS general score (R 2 = 0.088, p = 0.008), but not with the PANSS positive scores and PANSS negative scores. Serum IGF-1 levels were not related to the prevalence of diabetes (p = 0.64). However, a significant correlation was observed between serum IGF-1 levels and age (B = -1.88, p < 0.0001). Serum IGF-1 levels could not distinguish patients with schizophrenia and healthy controls. Conclusion: The association between serum IGF-1 levels and psychiatric symptoms may be complicated in patients with chronic schizophrenia.

CT imaging findings of anti-PD-1 inhibitor-related enterocolitis.

PURPOSE: Immune checkpoint inhibitors promote the antitumor activity of T cells; however, there is a risk of side effects. The aim of this study was to characterize the computed tomography (CT) findings of one such side effect, anti-programmed cell death-1 antibody-related enterocolitis (αPD-1-EC). METHODS: This single-institution retrospective study included 21 patients with αPD-1-EC who underwent CT between January 2015 and April 2020. Two board-certified radiologists independently evaluated the CT findings, including the pattern of intestinal wall enhancement, maximum bowel wall thickness, maximum appendiceal diameter, and involvement of enterocolitis in each intestinal segment. Symptoms and their severity were also investigated. RESULTS: Pancolitis and skip lesions involving both the rectosigmoid colon and the cecum were found in 9 patients each (42.9%). The rectum was the most frequently involved lesion (18/21, 85.7%), and appendiceal involvement was found in 11 patients (52.4%). The most frequent wall enhancement pattern was the gray pattern (i.e., mild homogeneous enhancement of the thickened bowel wall). The mean maximum diameter of the involved appendix was 9.6 ± 4.5 mm (range 4.5-18 mm). Frequent symptoms included diarrhea (21/21), fever (8/21), and abdominal pain (7/21). Other concomitant immune-related adverse events were found in 6 patients. CONCLUSIONS: Pancolitis, skip lesions, and appendiceal involvement were frequent in patients with αPD-1-EC. When combining these characteristic findings with other clinical findings, such as low-grade diarrhea, other concomitant immune-related adverse events, and anti-PD-1 therapy administration, CT may be a useful diagnostic tool for αPD-1-EC.