Immune-related Liver Injury is a Poor Prognostic Factor in Patients with Nonsmall Cell Lung Cancer Treated with Immune Checkpoint Inhibitors

The correlation between immune-related adverse events and efficacy of immune checkpoint inhibitors

Immune checkpoint inhibitors have revolutionized cancer treatment by targeting the cytotoxic T lymphocyte antigen-4 and programmed death-1/ligand-1. Although immune checkpoint inhibitors show promising therapeutic efficacy, they often cause immune-related adverse events. Immune-related adverse events differ from the side effects of conventional chemotherapy and require vigilant monitoring. These events predominantly affect organs, such as the colon, liver, lungs, pituitary gland, thyroid and skin, with rare cases affecting the heart, nervous system and other tissues. As immune-related adverse events result from immune activation, indicating the reinvigoration of exhausted immune cells that attack both tumors and normal tissues, it is theoretically possible that immune-related adverse events may signal a better response to immune checkpoint inhibitor therapy. Recent retrospective studies have explored the link between immune-related adverse event development and clinical efficacy; however, the predictive value of immune-related adverse events in the immune checkpoint inhibitor response remains unclear. Additionally, studies have focused on immune-related adverse events, timing of onset and immunosuppressive treatments. This review focuses on pivotal studies of the association between immune-related adverse events and outcomes in patients treated with immune checkpoint inhibitors.

Outcomes of immune checkpoint inhibitor-induced liver toxicity managed by hepatologists in a multidisciplinary toxicity team

AIM

To detect immune-related adverse events (irAEs) early and treat them appropriately, our institute established an irAE-focused multidisciplinary toxicity team in cooperation with various departments. This study aimed to evaluate a consultation system involving a team of hepatologists in terms of its utility for the management of severe immune checkpoint inhibitor (ICI)-induced liver toxicity.

METHODS

To analyze the diagnosis and treatment of severe ICI-induced liver toxicity (Grade 2 requiring corticosteroid therapy and Grade 3 or higher), we examined patients' clinical courses before and after the hepatologist consultation system was established (pre-period, September 2014 to February 2019; post-period, March 2019 to March 2023).

RESULTS

The median follow-up period was 392 days. Of the 1247 patients with advanced malignancies treated with ICIs, 66 developed severe ICI-induced liver toxicity (n = 22 and 44 in the pre- and post-periods, respectively). In the pre-period, hepatologist consultations were sought for 15/22 patients, whereas in the post-period, 42/44 patients were referred to and treated by hepatologists. The time from the onset of liver toxicity to the consultation was significantly shorter in the post-period than in the pre-period (mean 1.9 vs. 6.5 days, respectively; p = 0.012). The number of patients with a biopsy-confirmed diagnosis of ICI-induced liver toxicity was significantly higher in the post-period than in the pre-period (n = 22 vs. n = 3, respectively; p = 0.006). Finally, there were no cases of immune-related cholangitis in the pre-period, compared to five cases in the post-period.

CONCLUSION

A hepatologist consultation system in an irAE-focused multidisciplinary toxicity team is useful for managing severe ICI-induced liver toxicity.

Predicting Outcomes of Atezolizumab and Bevacizumab Treatment in Patients with Hepatocellular Carcinoma

A combination of atezolizumab with bevacizumab (AB) is the first regimen that has shown superiority compared to sorafenib and is now being used as the systemic treatment of choice for hepatocellular carcinoma (HCC) patients with Barcelona Liver Cancer Clinic stage C. However, a considerable number of patients do not achieve survival or significant responses, indicating the need to identify predictive biomarkers for initial and on-treatment decisions in HCC patients receiving AB. In this manuscript, we summarized the current data from both experimental and clinical studies. This review will be beneficial for both clinicians and researchers in clinical practice as well as those designing experimental, translational, or clinical studies.

Abdominal pain accompanied by elevated serum inflammatory markers and biliary enzymes for diagnosing immune checkpoint inhibitor-induced sclerosing cholangitis

Immune-related sclerosing cholangitis (irSC) is relatively rare and its clinical characteristics are not well known. In this study, we aimed to summarize the clinical features of irSC. Clinical data were collected retrospectively from 1,393 patients with advanced malignancy treated with immune-checkpoint inhibitors (ICIs) between August 2014 and October 2021. We analyzed patients with immune-related adverse events of liver injury (liver-irAEs) and compared irSC and non-irSC groups. Sixty-seven patients (4.8%) had a liver-irAE (≥ grade 3) during the follow-up period (median, 262 days). Among these, irSC was observed in eight patients (11.9%). All patients in the irSC group were treated with anti-PD-1/PD-L1 antibodies. Compared with the non-irSC group, the irSC group showed mainly non-hepatocellular liver injury (87.5 % vs 50.8 %, P = 0.065), and had elevated serum inflammatory markers (e.g., CRP and NLR) and biliary enzymes (e.g., GGTP and ALP) at the onset of liver-irAEs. Furthermore, most patients with irSC had abdominal pain. In the non-irSC group, the liver injury of 23 patients improved only with the discontinuation of ICIs, and 22 patients improved with medication including prednisolone (PSL). Conversely, almost all patients (n=7) in the irSC group were treated with PSL, but only two patients experienced an improvement in liver injury. We found that irSC is characterized by a non-hepatocellular type of liver injury with abdominal pain and a high inflammatory response and is refractory to treatment. Further examination by imaging is recommended to detect intractable irSC in cases with these characteristics.

Effects on survival of the adverse event of atezolizumab plus bevacizumab for hepatocellular carcinoma: a multicenter study by the Japan Red Cross Liver Study Group

This study aimed to describe the real-world efficacy and safety of the combination therapy of atezolizumab and bevacizumab (Atezo/Bev) for unresectable hepatocellular carcinoma (HCC). This retrospective analysis of a multicenter registry cohort included 268 patients treated with Atezo/Bev. The incidence of adverse events (AE) and its impact on overall survival (OS) and progression-free survival (PFS) were analyzed. Of the 268 patients, 230 (85.8%) experienced AE. The median OS and PFS in the whole cohort were 462 and 239 days, respectively. The OS and PFS were not different in terms of AE, but they were significantly shorter in patients with increased bilirubin level and those with increased aspartate aminotransferase (AST) or alanine aminotransferase (ALT). Regarding increased bilirubin level, the hazard ratios (HRs) were 2.61 (95% confidence interval [CI]: 1.04-6.58, P = 0.042) and 2.85 (95% CI: 1.37-5.93, P = 0.005) for OS and PFS, respectively. Regarding increased AST or ALT, the HRs were 6.68 (95% CI: 3.22-13.84, P < 0.001) and 3.54 (95% CI: 1.83-6.86, P < 0.001) for OS and PFS, respectively. Contrarily, the OS was significantly longer in patients with proteinuria (HR: 0.46 [95% CI: 0.23-0.92], P = 0.027). Multivariate analysis confirmed that proteinuria (HR: 0.53 [95% CI: 0.25-0.98], P = 0.044) and increased AST or ALT (HR: 6.679 [95% CI: 3.223-13.84], P = 0.003) were independent risk factors for a shorter OS. Furthermore, analysis limited to cases who completed at least 4 cycles confirmed that increased AST or ALT and proteinuria were negative and positive factors for OS, respectively. In the real-world setting, increased AST or ALT and bilirubin level during Atezo/Bev treatment were found to have a negative impact on PFS and OS, whereas proteinuria had a positive impact on OS.

Clustering using unsupervised machine learning to stratify the risk of immune-related liver injury

BACKGROUND AND AIM

Immune-related liver injury (liver-irAE) is a clinical problem with a potentially poor prognosis.

METHODS

We retrospectively collected clinical data from patients treated with immune checkpoint inhibitors between September 2014 and December 2021 at the Nagoya University Hospital. Using an unsupervised machine learning method, the Gaussian mixture model, to divide the cohort into clusters based on inflammatory markers, we investigated the cumulative incidence of liver-irAEs in these clusters.

RESULTS

This study included a total of 702 patients. Among them, 492 (70.1%) patients were male, and the mean age was 66.6 years. During the mean follow-up period of 423 days, severe liver-irAEs (Common Terminology Criteria for Adverse Events grade ≥ 3) occurred in 43 patients. Patients were divided into five clusters (a, b, c, d, and e). The cumulative incidence of liver-irAE was higher in cluster c than in cluster a (hazard ratio [HR]: 13.59, 95% confidence interval [CI]: 1.70-108.76, P = 0.014), and overall survival was worse in clusters c and d than in cluster a (HR: 2.83, 95% CI: 1.77-4.50, P < 0.001; HR: 2.87, 95% CI: 1.47-5.60, P = 0.002, respectively). Clusters c and d were characterized by high temperature, C-reactive protein, platelets, and low albumin. However, there were differences in the prevalence of neutrophil count, neutrophil-to-lymphocyte ratio, and liver metastases between both clusters.

CONCLUSIONS

The combined assessment of multiple markers and body temperature may help stratify high-risk groups for developing liver-irAE.

Association between Adverse Events and Prognosis in Patients with Hepatocellular Carcinoma Treated with Atezolizumab Plus Bevacizumab: A Multicenter Retrospective Study

This study aimed to evaluate the correlation between adverse events (AEs) and overall survival (OS) in patients with unresectable hepatocellular carcinoma treated with atezolizumab plus bevacizumab (atezo/beva). This was a multicenter study in which 130 patients were enrolled. Hypertension and skin disorders had a significant correlation with longer survival (median survival time (MST): not reached vs. 14.3 months and not reached vs. 14.8 months, p = 0.001 and p = 0.047, respectively). In contrast, liver injuries were significantly correlated with shorter survival (MST: 14.7 months vs. not reached, p = 0.036), and the median development time was 21 days. In a logistic regression analysis, fatigue ≥ grade 2, liver injury ≥ grade 3, and modified albumin–bilirubin grade 2b were identified as independent factors for discontinuation due to AEs. The OS in the no discontinuation due to AE group was significantly longer than that in the discontinuation due to AEs group (MST not reached vs. 11.2 months, p = 0.001). We concluded that the development of liver injury was a negative factor for OS and that we should be vigilant in monitoring AE during atezo/beva treatments.

Diagnostic impact of 18F-FDG PET/CT imaging on the detection of immune-related adverse events in patients treated with immunotherapy

INTRODUCTION

Immunotherapy is an effective treatment method for cancer cells with humoral and cellular immune mechanisms of action but triggers an inflammatory response and disrupts standard protective immune tolerance. Early detection of immune-related adverse events (irAEs) on PET/CT is crucial for patient management and subsequent therapy decisions. In this study, we aimed to evaluate the impact of ¹⁸F-FDG PET/CT on detecting of irAEs in patients receiving immunotherapy.

PATIENTS AND METHODS

Forty-six patients with advanced RCC (n: 32), malign melanoma (n: 9), lung cancer (n: 4), and laryngeal carcinoma (n: 1), who underwent ¹⁸F-FDG PET/CT imaging for response assessment after immunotherapy, were enrolled in the study. Newly detected findings associated with irAEs on posttreatment PET/CT images were compared with the pretreatment PET/CT, both qualitatively and semi-quantitatively.

RESULTS

Twenty-eight (61%) patients developed irAEs as observed on PET/CT. Enteritis/colitis was the most frequent irAE visualized on PET/CT with 13 patients (28.2%), followed by gastritis (17.3%), thyroiditis (13%), and myositis/arthritis (13%). Hepatitis (6.5%), pneumonitis (6.5%), sarcoid-like reaction (4.3%), and hypophysitis (4.3%) were observed to a lesser extent. The median time between the appearance of irAEs on PET/CT and the initiation of immunotherapy was 4.3 months. There were no significant differences in age, sex, and treatment response status of patients with and without irAEs.

CONCLUSION

¹⁸F-FDG PET/CT plays a fundamental role in cancer immunotherapy with the potential to show significant irAEs both in the diagnosis and in follow-up of irAEs. IrAEs were present on PET/CT images of more than half of the patients who received immunotherapy in our study.