Workup and Management of Immune-Mediated Hepatobiliary Pancreatic Toxicities That Develop During Immune Checkpoint Inhibitor Treatment

Absence of Survival Impact from Hepatitis During Immunotherapy in 193 Patients with Advanced Hepatocellular Carcinoma - An Observational Study from Taiwan

Background

Hepatitis often occurs after initiating immune checkpoint inhibitor (ICI) treatment. The time and grade of hepatitis after ICI starts and the prognostic role of immune-related hepatitis in patients with advanced hepatocellular carcinoma (aHCC) remain unclear.

Methods

In this real-world analysis, we enrolled aHCC patients receiving ICIs, documented the highest level of liver enzymes during/after ICIs, and analyzed the survival impact of different hepatitis patterns.

Results

One hundred and ninety-three aHCC patients receiving ICIs were recruited. During ICIs, 88.6% of patients experienced aspartate transaminase (AST) elevations (Grade III/IV: 7.8%). For alanine transaminase (ALT), 81.3% had elevated levels (Grade III/IV: 3.6%), and 41.5% of patients had elevated bilirubin levels (Grade 3/4: 6.7%). The median AST, ALT, and total bilirubin values significantly increased after ICI treatment initiated (all p < 0.001) and, similarly, after excluding progressive disease (p = 0.014, p = 0.002, p < 0.001). The median time of hepatitis occurrence is from the 4.0th to 15.9th weeks. Multivariable analysis showed that patterns of liver enzyme change of AST and total bilirubin in patients receiving ICIs significantly correlate to overall survival (OS, p = 0.009 and 0.001, respectively). After ICI termination, patients with elevated bilirubin (p = 0.003) and AST (p = 0.005) would indicate poor survival, with adjustment of viral hepatitis and ICI responses.

Conclusion

Hepatitis emerges between the 4th and 20th weeks post-ICI initiation. Changes in liver enzymes during ICI therapy do not directly affect OS, implying the safety of ICI use when corticosteroids are promptly administered if clinically indicated.

Immune Checkpoint Inhibitors in Cancer Treatment and Incidence of Pancreatitis

Immune checkpoint inhibitors (ICIs) are an approved therapy for the management of various advanced neoplasms. Limited reviews focus on the influence of this therapy resulting in pancreatitis. This review discusses the relationship between ICIs and their effects on the pancreas, including the incidence of pancreatitis, immunotherapy, programmed cell death 1 (PD-1) receptors, driver mutations, programmed death ligand 1 (PD-L1), and immune-related adverse events. Additionally, it focuses on the clinical presentations, diagnosis, case studies, and mechanisms by which ICIs activate different pathways to cause pancreatitis. We conducted a comprehensive literature search using PubMed, Cochrane Library, and Google Scholar databases to identify relevant studies on ICI-associated pancreatitis. The review explores the incidence and epidemiology of ICI-induced pancreatitis, its clinical presentation, diagnostic criteria, and management strategies.The overall incidence of ICI-induced pancreatitis is estimated at 1-2%, with higher rates observed in combination therapy. Clinical presentations range from asymptomatic enzyme elevations to severe pancreatitis. Diagnosis relies on a combination of clinical symptoms, elevated pancreatic enzymes, and imaging findings, with MRI and endoscopic ultrasound showing promise in early detection. Management strategies include IV fluid administration, pain control, and nutritional support. The efficacy of corticosteroids remains controversial, and alternative immunosuppressants are being explored for steroid-refractory cases. Long-term monitoring is crucial due to the risk of chronic pancreatitis and pancreatic insufficiency. This review highlights the need for further research to elucidate the exact mechanisms of ICI-associated pancreatic injury, develop predictive biomarkers, and refine treatment protocols. As ICI use continues to expand, a thorough understanding of this adverse event is essential for optimizing patient care and outcomes in cancer immunotherapy.

Clinical characteristics, treatment and outcome of pembrolizumab-induced acute pancreatitis

Acute pancreatitis (AP) is a rare adverse event of pembrolizumab with unclear clinical features. This study investigated the clinical features of pembrolizumab-induced AP to provide a reference for prevention and treatment. Case reports, case series and clinical studies of pembrolizumab-induced AP were collected by searching Chinese and English databases up to January 31, 2024. Thirty-one patients were included, with a median age of 59 years (range 39, 82). The median time from administration to onset of AP was 5.05 months (range 0.5, 16) and the median cycle was 7 cycles (range 1, 35). Twenty-two (71.0%) patients had elevated pancreatic amylase with a median value of 860 IU/L (range 105-12562), and 16 (51.6%) patients had elevated lipase with a median value of 282 IU/L (range 153-1034). Pancreatic biopsy showed neutrophil infiltration (9.7%) and lymphocyte infiltration (6.5%). Immunohistochemical staining showed CD8 dominated inflammatory infiltration (6.5%). The computed tomography showed diffuse enlargement (51.6%) and focal enlargement (51.6%) of the pancreas. Endoscopic ultrasound showed enlarged hypoechoic pancreas(16.1%). PET/CT showed increased FDG uptake (16.1%). The magnetic resonance cholangial pancreatography showed narrowing of main pancreatic duct (12.9%). AP symptoms and pancreatic enzymes improved after discontinuation of pembrolizumab and administration of steroids and infliximab. Clinicians should be aware that AP is a rare adverse reaction to pembrolizumab. Pembrolizumab induced AP can be initiated with steroids for control, and infliximab can be initiated with steroid-refractory AP.

Reaching the Diagnosis of Checkpoint Inhibitor-Induced Diabetes Mellitus in Different Clinical Scenarios: A Real-World Application of Updated Diagnostic Criteria

BACKGROUND

Checkpoint inhibitor (CPI)-associated diabetes mellitus (CPI-DM) is a rare immune-related adverse event (irAE) that presents with variable clinical manifestations. Data about its pathogenesis have not yet been adequately studied.

METHODS

Applying the recently updated diagnostic criteria from the American Diabetes Association, we retrospectively reviewed the medical records of all CPI-treated patients referred to our endocrinological unit for managing their endocrine irAEs and analyzed the incidence of CPI-DM, its clinical characteristics, and its management.

RESULTS

Among the 326 CPI-treated patients with endocrine irAEs, 4 patients met the updated criteria for the diagnosis of CPI-DM, representing 1.22% of all endocrine irAEs in our cohort. These four patients presented with distinct clinical scenarios regarding the irAE onset, the underlying malignancy, the administered CPI regimen, and the type of circulating autoantibodies.

CONCLUSION

The variable presentation of CPI-DM and the non-standard sensitivity of the presence of the type 1 DM traditional autoantibodies highlight the need for distinct guidelines and increased awareness of its diagnosis and management.

Immune Checkpoint Inhibitor-related Pancreatitis: A Case Series, Review of the Literature and an Expert Opinion

Immune checkpoint inhibitors (ICIs) have revolutionized the treatment of various malignancies, but are associated with serious adverse events like pancreatitis. Current guidelines are limited to the first step in treating acute ICI-related pancreatitis with steroids but lack treatment advices for steroid dependent pancreatitis. We describe a case series of 3 patients who developed ICI-related pancreatitis with chronic features such as exocrine insufficiency and pancreatic atrophy at imaging. Our first case developed after treatment with pembrolizumab. The pancreatitis responded well after discontinuation of immunotherapy but imaging showed pancreatic atrophy and exocrine pancreatic insufficiency persisted. Cases 2 and 3 developed after treatment with nivolumab. In both, pancreatitis responded well to steroids. However during steroid tapering, pancreatitis recurred and the latter developed exocrine pancreatic insufficiency and pancreatic atrophy at imaging. Our cases demonstrate resemblances with autoimmune pancreatitis based on clinical and imaging findings. In line, both diseases are T-cell mediated and for autoimmune pancreatitis azathioprine is considered as maintenance therapy. Guidelines of other T-cell mediated diseases like ICI-related hepatitis suggest tacrolimus. After adding tacrolimus in case 2 and azathioprine in case 3, steroids could be completely tapered and no new episodes of pancreatitis have occurred. These findings support the idea that the treatment modalities for other T-cell mediated diseases are worthwhile options for steroid dependent ICI-related pancreatitis.

Pancreatic adverse events of immune checkpoint inhibitors therapy for solid cancer patients: a systematic review and meta-analysis

Objective

This review aims to determine the incidence and risk of pancreatic adverse events (AEs) associated with immune checkpoint inhibitors (ICIs) therapy for solid tumors.

Methods

We conducted a comprehensive systematic literature search in PubMed, Embase, and Cochrane Library up to March 15, 2023, to identify all randomized controlled trials comparing ICIs with standard treatment in solid tumors. We included studies that reported immune-related pancreatitis or elevation of serum amylase or lipase levels. Following protocol registration in PROSPERO, we conducted a systematic review and meta-analysis.

Results

59 unique randomized controlled trials with at least one ICI-containing arm (41 757 patients) were retrieved. The incidences for all-grade pancreatitis, amylase elevation and lipase elevation were 0.93% (95% CI 0.77-1.13), 2.57% (95% CI 1.83-3.60) and 2.78% (95% CI 1.83-4.19), respectively. The incidences for grade ≥3 pancreatitis, amylase elevation and lipase elevation were 0.68% (95% CI 0.54-0.85), 1.17% (95% CI 0.83-1.64) and 1.71% (95% CI 1.18-2.49), respectively. The use of ICIs was associated with an increased risk of all-grade pancreatic immune-related AEs (irAEs) including pancreatitis (OR=2.04, 95% CI 1.42-2.94, P =0.0001), amylase elevation (OR=1.91, 95% CI 1.47-2.49, P < 0.0001) and lipase elevation (OR=1.77, 95% CI 1.37-2.29, P < 0.0001). In addition to these, the post-hoc analysis found that PD-1 inhibitors had a significant higher risk of pancreatic AEs compared with PD-L1 inhibitors and the patients undergoing dual ICI therapy were at a significantly higher risk of pancreatic AEs than the patients receiving single ICI therapy.

Conclusion

Our study provides an overview of the incidence and risk of ICI-associated pancreatitis and pancreatic enzyme elevations in the treatment of solid tumors. Our findings may help raise awareness among clinicians of the potential for ICI-associated pancreatic AEs in clinical practice.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO, identifier 345350.

Immune checkpoint inhibitor-induced hepatitis injury: risk factors, outcomes, and impact on survival

PURPOSE

Immune checkpoint inhibitors (ICIs) are associated with a unique set of immune-related adverse events (irAEs). Few studies have evaluated the risk factors and outcomes of patients who develop ICI-induced hepatitis (ICIH).

METHODS

We utilized an institutional database of patients with advanced cancers treated with ICI to identify patients with ICIH. irAEs were graded using the Common Terminology Criteria for Adverse Events v4. Overall survival (OS) was calculated from the date of ICI to death from any cause or the date of the last follow-up. OS with 95% confidence intervals were estimated using the Kaplan-Meier method and stratified by the occurrence of ICIH.

RESULTS

We identified 1096 patients treated with ICI. The most common ICIs were PD1/L1 (n = 774) and CTLA-4 inhibitors (n = 195). ICIH occurred among 64 (6%) patients: severity was < grade 3 in 30 and ≥ grade 3 in 24 patients (3.1% overall). Median time to ICIH was 63 days. ICIH was more frequent in women (p = 0.038), in patients treated with combination ICIs (p < 0.001), and when given as first-line therapy (p = 0.018). Occurrence of ICIH was associated with significantly longer OS, median 37.0 months (95% CI 21.4, NR) compared to 11.3 months (95% CI 10, 13, p < 0.001); there was no difference in OS between patients with ≥ grade 3 ICIH vs grade 1-2.

CONCLUSIONS

Female sex, combination immunotherapy, and the first line of immunotherapy were associated with ICIH. Patients with ICIH had improved clinical survival compared to those that did not develop ICIH. There is a need for prospective further studies to confirm our findings.

Pancreatic involvement due to immune checkpoint inhibitors: a proposed classification

BACKGROUND

Drug-induced acute pancreatitis (AP) is uncommon and pancreatic involvement due to immune checkpoint inhibitors (ICI) in published reports relied on the National Cancer Institute's (NCI) Common Terminology Criteria for Adverse Events (CTCAE). CTCAE definition of AP differs from the revised Atlanta classification diagnostic criteria. This study aims to classify the spectrum of pancreatic involvement in patients receiving ICI therapy into categories built on the revised Atlanta classification.

METHODS

A retrospective cohort study of cancer patients receiving cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) and programmed cell death protein 1 (PD-1) inhibitors between 2011 and 2020. Pancreas-specific immune-related adverse events (irAEs) were categorized into AP and pancreatic injury.

RESULTS

Forty-seven patients on ICI therapy met selection criteria. Twenty patients (43%) had AP, while 27 (57%) had pancreatic injury. Fifteen patients (75%) developed mild AP. Five patients progressed to pancreatic atrophy, and two patients (4%) developed exocrine pancreatic insufficiency. In both groups, most patients received nivolumab therapy (70% vs. 67%, p = 0.08) with no difference in mean number of nivolumab doses (9 vs. 10, p = 0.69). There was no correlation between the mean number of nivolumab or pembrolizumab doses and AP events (OR 0.94, p = 0.26, and OR 0.98, p = 0.86), but the duration of ICI therapy was significantly related to pancreatic atrophy (OR 1.01, p = 0.05; 95% CI 1.00-1.02).

CONCLUSION

Based on the novel classification, majority of pancreatic irAEs were classified as asymptomatic pancreatic injury but with some risk of pancreatic atrophy. This classification can help in assessing patterns of pancreatic involvement, pathogenesis, and treatment decisions.

Immune checkpoint inhibitor-induced myocarditis and myositis in liver cancer patients: A case report and literature review

With the development of immunotherapy, immune checkpoint inhibitors (ICIs) are widely used in clinical oncology and have achieved good results. ICIs could induce immune-related adverse events (irAEs) in cancer treatment, which warrant sufficient attention. Among them, immune myositis can manifest severe symptoms affecting the whole body, and immune myocarditis occurs with a low incidence but high fatality rate. Here we report a case of grade 3/4 adverse reactions in a patient with partial hepatectomy for malignancy after using ICIs and describe the clinical presentation, laboratory results, treatment, and prognosis. It emphasizes that clinicians should focus on being alert to irAEs in liver cancer patients who have received ICI therapy. The case we present is a 56-year-old male diagnosed with hepatocellular carcinoma. Right hepatic lobectomy was performed in April 2019. Postoperative follow-up showed that transcatheter arterial chemoembolization (TACE) combined with sorafenib (400 mg twice daily) failed to stop the recurrence of the tumor. In December 2020, the patient started to use Camrelizumab injections (200mg/injection every 21 days as a cycle). After 3 cycles, the patient had decreased muscle strength in both lower extremities with chest tightness, dyspnea, and expectoration (whitish sputum). The diagnosis was ICIs injection-induced immune myocarditis and myositis accompanied. The patient's condition improved considerably by steroid pulse therapy timely. The case emphasizes that clinicians should focus on being alert to irAEs in liver cancer patients who have received ICI therapy.

Immune-mediated hepatitis induced by immune checkpoint inhibitors: Current updates and future perspectives

In recent years, cancer immunotherapy has made remarkable achievements. Immune checkpoint inhibitors (ICIs) have been used successfully in several types of cancer in the past decade. However, expanded indication and increased use of Immune checkpoint inhibitors have resulted in increased reports of toxicity called immune-related adverse events (irAEs). Due to the unique immunological characteristics of the liver, a hepatic immune-related adverse events has also been reported, which is usually termed Immune-mediated hepatitis (IMH). So far, it is generally considered that the mechanism of IMH induced by Immune checkpoint inhibitors is mainly the overactivation of T cells. It has been reported that the incidence of IMH ranges from 1% to 15%. Because of the lack of specific markers, a diagnosis of exclusion of IMH is critical. Although most IMH is mild and recoverable, several death cases have been reported, which has been increasingly concerned. This review summarizes the current understanding of the pathophysiology, epidemiology, diagnosis, management and prognosis of IMH caused by Immune checkpoint inhibitors. It also discusses the controversial issues in IMH, such as the role of liver biopsy, grading criteria, risk factors, rational treatment strategies with steroids, and the timing of Immune checkpoint inhibitors rechallenging, which may provide helpful information for IMH in future clinical practice.

The Current status of steroid-refractory immune-checkpoint-inhibitor-related hepatotoxicity

ICI-related hepatotoxicity (IRH) is becoming more and more common as immune checkpoint inhibitors (ICIs) have begun to be increasingly approved and used in combination with other anti-tumor drugs worldwide. Steroids are the first choice for the treatment of IRH, but the subsequent optimal treatment algorithm remains unclear if the disease progresses to steroid-refractory IRH. Therefore, in this paper we reviewed all the pertinent literature on steroid-refractory IRH to the greatest extent possible in an attempt to provide information on which to base an update of the treatment algorithm for steroid-refractory IRH.

Neutrophil Infiltration and Acinar-ductal Metaplasia Are the Main Pathological Findings in Pembrolizumab-induced Pancreatitis

The histopathological findings of immune checkpoint inhibitor (ICI)-induced pancreatitis have rarely been reported. A 56-year-old man with squamous cell carcinoma of the lung with bone metastasis was being treated with pembrolizumab, an anti-programmed cell death protein-1 antibody. After 13 doses, he was referred to our department due to pancreatitis. Despite characteristic symptoms of acute pancreatitis, imaging findings were similar to those of autoimmune pancreatitis. However, a histological examination showed neutrophil-based inflammatory cell infiltration and acinar-ductal metaplasia. Immunostaining showed CD8-positive T lymphocyte infiltration. This case revealed the characteristic histopathology of pembrolizumab-induced pancreatitis, which was previously poorly understood.

Pancreatic injury following immune checkpoint inhibitors: A systematic review and meta-analysis

Background: Pancreatic injury (pancreatitis, amylase/lipase elevation) is a rare adverse event of immune checkpoint inhibitors (ICIs). With the high number of clinical studies on ICIs, the incidence and characteristics of associated pancreatic injury (PI) need to be reevaluated.

Methods: A systematic review and meta-analysis was conducted to assess the incidence of PI in cancer patients who received ICIs in randomized controlled trials (RCTs). PubMed, Embase, the ASCO, ESMO, and AACR conference proceedings before 1 April 2022, were investigated for relevant research.

Results: 50 RCTs involving 35,223 patients were included. The incidence of ICIs-PI was 2.22% (95% CI = 1.94%–2.53%). The incidence of PI was 3.76% (95% CI = 1.84–7.67%) when combining two ICIs, which was higher than single ICIs [2.25% (95% CI = 1.91–2.65%)]. The ICIs were ranked from high to low based on PI incidence: PD-L1 inhibitors 3.01% (95% CI = 1.86–4.87%), CTLA-4 inhibitors 2.92% (95% CI = 0.99–8.65%) and PD-1 Inhibitor 2% (95% CI = 1.67–2.39%). The ICI with the highest rate of PI was pembrolizumab 7.23.% (95% CI = 1.69–30.89%). In addition, the incidence of severe ICIs-PI was 2.08% (95% CI = 1.76–2.46%); and the incidence of severe PI was 2.32% (95% CI = 1.76–3.06%) when combining two ICIs, which was higher than single ICI [1.95% (95% CI = 1.58–2.41%)]. The ICIs were ranked from high to low according to the incidence of severe PI: PD-L1 inhibitors 3.1% (95% CI = 1.7–5.64%), CTLA-4 inhibitors 2.69% (95% CI = 0.76–9.49%), PD-1 inhibitors 1.80% (95% CI = 1.41–2.29%).

Conclusion: Treatment with multiple ICIs result in a higher incidence of PI compared to single ICIs, irrespective of the grade of pancreatic injury. The incidence of PI caused by PD-L1 inhibitors is higher than that of CTLA-4 inhibitors and PD-1 Inhibitor, and Pembrolizumab has the highest rate of ICIs-PI. Although the incidence of ICIs-PI is not high, they are usually severe (≥ grade 3 events).

Endoscopic ultrasound guided interventions in the management of pancreatic cancer

There has been a growing interest in developing endoscopic ultrasound (EUS)-guided interventions for pancreatic cancer, some of which have become standard of care. There are two main factors that drive these advancements to facilitate treatment of patients with pancreatic cancer, ranging from direct locoregional therapy to palliation of symptoms related to inoperable pancreatic cancer. Firstly, an upper EUS has the capability to access the entire pancreas-lesions in the pancreatic head and uncinate process can be accessed from the duodenum, and lesions in the pancreatic body and tail can be accessed from the stomach. Secondly, there has been a robust development of devices that allow through-the-needle interventions, such as placement of fiducial markers, brachytherapy, intratumoral injection, gastroenterostomy creation, and ablation. While these techniques are rapidly emerging, data from a multicenter randomized controlled trial for some procedures are awaited prior to their adoption in clinical settings.

Drug-induced bile duct injury: new agents, new mechanisms

PURPOSE OF REVIEW

Drug-induced bile duct injury can be caused by a long list of agents. In most cases, damage is because of T-cell-mediated idiosyncratic reactions. Recently, a number of new agents, including not only drugs but also herbal supplements, have been incriminated and new mechanisms of bile duct injury have emerged. This review will focus on these new data.

RECENT FINDINGS

New members of drug families already known to be responsible for bile duct injury have been incriminated. New players have been identified, such as herbal supplements, like kratom, and recreational drugs, such as ketamine used outside the medical setting. Anticytokine monoclonal antibodies are rarely involved. In contrast, antineoplastic treatments are of growing concern, especially immune checkpoint inhibitors, which induce immune-related adverse effects because of the excessive stimulation of the immune system and its lack of regulation.

SUMMARY

Two patterns of bile duct injury are recognized. Drug-induced small-duct cholangiopathies target the smaller bile ducts; acute injuries eventually progress to chronic disease in the form of the vanishing bile duct syndrome. Drug-induced sclerosing cholangitis target large bile ducts, with a protracted chronic course; the onset of symptoms may be delayed after drug discontinuation; potentially severe, life-threatening complications can occur.

Biomarkers and risk factors for the early prediction of immune-related adverse events: a review

In recent years, immunotherapy has been widely used to treat patients with malignant tumors. While immune checkpoint inhibitors (ICIs) significantly improve the prognosis of cancer patients, the incidence of immune-related adverse events (irAEs) is increasing. Not only can irAEs accumulate in multiple organ systems throughout the body, but rare adverse reactions may also occur continuously. In severe cases, irAEs can be life-threatening or even lead to death. Therefore, the early identification, diagnosis and treatment of irAEs are very important. Early identification of patients with high-risk irAEs as well as the reduction or avoidance of severe irAEs have important clinical significance. This article will review the research progress of early predictive biomarkers and risk factors for the occurrence of irAEs and propose potential future directions for follow-up research and clinical applications.

Clinical-radiological characteristics and intestinal microbiota in patients with pancreatic immune-related adverse events

BACKGROUND

The pancreatic immune-related adverse event (irAE) is a rare but increasingly occurrence disease with limited knowledge, which was associated with the use of immune checkpoint inhibitors (ICIs).

METHODS

In this case series study of pancreatic irAE patients, clinical and radiological manifestations are summarized. Baseline and post-treatment fecal microbiota of immune-related acute pancreatitis (irAP) patients were analyzed by the 16 s rDNA amplicon sequencing method.

RESULTS

A total of six patients were enrolled into the study, and the onset of pancreatic irAEs occurred a median of 105 days after a median of 4.5 cycles with immune checkpoint inhibitors (ICIs). All patients had an effective response to ICIs. Abdominal pain was the main clinical manifestation. Serum amylase (sAMY) and lipase (sLIP) had dynamic changes parallel to clinical severity. Contrast-enhanced computed tomography (CT) did not accurately reveal the level of inflammation. However, magnetic resonance imaging (MRI) was a sensitive imaging method which showed decreased and increased signal intensity of pancreatic parenchyma in T1-weighted fat-saturated and diffusion-weighted imaging, respectively. Glucocorticoids were the main treatment with a rapid initial effect followed by a slow improvement. After reinitiation of ICI therapy, pancreatic irAEs either deteriorated, remained stable or the patient developed severe pancreatic β-cell destruction without irAP recurrence. The baseline microbiota of irAP had low Bacteroidetes/Firmicutes ratio at phylum level, low relative abundance of Alistipes, Bacteroides and high Lachnospiraceae at genus level, compared to levels of pancreatic β-cell destruction and post-treatment of irAP.

CONCLUSIONS

Pancreatic irAE patients had corresponding abdominal pain and increase in sAMY/sLIP. MRI was found to be an ideal imaging modality. Treatment with glucocorticoids were the main approach. The microbiota showed relative changes at baseline and during treatment.

Hepatitis B reactivation and immune check point inhibitors

Liver toxicity during immune checkpoint inhibitor treatment is mostly due to immune mediated hepatitis. Viral hepatitis, as well as auto-immune or metabolic hepatitis, are considered as exclusion criteria for ICI induced immune hepatitis diagnosis. However, considering the high prevalence of viral hepatitis B infection and the increasing prescription of immune checkpoint inhibitors, their use in patients with HBV chronic viral infection may be common, even more if patients are treated for hepatocellular carcinoma. Few clinical studies directly deal with the risk of HBV reactivation during ICI therapy and real-life data is currently based on five reported cases of HBV reactivation, one with fatal outcome. In this review, we summarize the current available clinical information about HBV reactivation risk during ICI treatment, its hypothetic mechanism, and propose practical recommendations about verifying and monitoring HBV status throughout the treatment.

PD-1/PDL1 Blockade Exacerbates Pancreatic Damage and Immune Response in a Mouse Model of Acute Pancreatitis

Programmed necrosis factor 1 (PD-1) is significantly overexpressed in lymphocytes, neutrophils, and macrophages and has been studied in depth in tumors. As a member of the negative costimulatory family of immune regulatory molecules, expression of PD-1 and its primary regulatory pathway are related to immune cells. Recently, PD-1 was demonstrated to be clinically important in inflammatory diseases, such as multiple sclerosis, glomerulonephritis, and inflammatory bowel disease. PD-1, a negative regulator molecule, was recently found to protect tissues from the inflammatory response and inflammatory cell infiltration. Conversely, PD-1 deficiency may contribute to the occurrence of a diverse array of inflammatory diseases. However, whether PD-1 regulates the pathogenesis of acute pancreatitis (AP) is unclear. AP is a noninfectious inflammatory disease with primary pathological manifestations that include edema, inflammatory cell infiltration, and acinar cell necrosis. Among these features, costimulatory molecules including PD-1/PDL1 play a critical role in the regulation of immune response and immune activation. Here, we first found that PD-1 is notably upregulated in neutrophils and macrophages in peripheral blood and pancreatic injury tissue in AP mice. PD-1 gene deficiency exacerbated pancreatic injury in an experimental mouse model of AP. We observed more severe pancreatic injury in PD-1-deficient mice than in control mice, including increased pancreatic edema, inflammatory cells, infiltration, and acinar cell necrosis. We also found that PD-1-deficient mice exhibited higher levels of serum enzymology and inflammatory factors in AP. Furthermore, PD-1/PDL1 neutralizing antibodies significantly aggravated pancreatic and lung injury and increased serum inflammatory cytokine levels. These findings were consistent with those in PD-1-deficient mice. In summary, PD-1 may protect against AP in mice and act as a potential target for the prevention of AP in the future.

Reassessing Patterns of Response to Immunotherapy with PET: From Morphology to Metabolism

Cancer demands precise evaluation and accurate and timely assessment of response to treatment. Imaging must be performed early during therapy to allow adjustments to the course of treatment. For decades, cross-sectional imaging provided these answers, showing responses to the treatment through changes in tumor size. However, with the emergence of immune checkpoint inhibitors, complex immune response patterns were revealed that have quickly highlighted the limitations of this approach. Patterns of response beyond tumor size have been recognized and include cystic degeneration, necrosis, hemorrhage, and cavitation. Furthermore, new unique patterns of response have surfaced, like pseudoprogression and hyperprogression, while other patterns were shown to be deceptive, such as unconfirmed progressive disease. This evolution led to new therapeutic evaluation criteria adapted specifically for immunotherapy. Moreover, inflammatory adverse effects of the immune checkpoint blockade were identified, many of which were life threatening and requiring prompt intervention. Given complex concepts like tumor microenvironment and novel therapeutic modalities in the era of personalized medicine, increasingly sophisticated imaging techniques are required to address the intricate patterns of behavior of different neoplasms. Fluorine 18-fluorodeoxyglucose PET/CT has rapidly emerged as one such technique that spans both molecular biology and immunology. This imaging technique is potentially capable of identifying and tracking prognostic biomarkers owing to its combined use of anatomic and metabolic imaging, which enables it to characterize biologic processes in vivo. This tailored approach may provide whole-body quantification of the metabolic burden of disease, providing enhanced prediction of treatment response and improved detection of adverse events. ^©RSNA, 2020.

[Management of immune checkpoint inhibitors-induced liver toxicity in cancer]

Pharmacological immune checkpoint inhibitors (ICI) restore the anti-tumor properties of T-lymphocytes, but unfortunately can engender auto-immune-like disorders. Those, frequent and of variable severity, sometimes target the liver parenchyma. Liver toxicity of ICI firstly leads to alteration of liver function tests (ALFT) with a risk of clinical decompensation. The appearance of ALFT should lead the clinician to exclude a non-immunological injury or a tumoral invasion of the liver parenchyma. In case of high grade ALFT, liver biopsy is necessary for diagnosis purpose. In ICI-induced hepatoxicity, histology examination shows most frequently a lobular acute hepatitis associated with lymphocytic infiltrates, but with different features than those encountered in primary auto-immune hepatitis. The management of ICI-related ALFT depends of their severity. Discontinuation of ICI is recommended for ALFT≥grade 2, and corticosteroid therapy for ALFT≥grade 3, or grade 2 without any improvement after ICI discontinuation. Addition of mycophenolate may be indicated whether corticosteroid inefficiency. Reintroduction of ICI is inadvisable for the most severe toxicities. The management of ALFT occurring on underlying chronic hepatopathy has not got consensual guidelines so far, but they should take account of the basal grade of ALFT and their worsening level under ICI therapy. The situation becomes more complex with associations between ICI and anti-angiogenic agents or cytotoxic chemotherapies where each of the drugs can be hepatotoxic. Thus, liver biopsy is primordial to figure out the mechanism of liver toxicity.

Steroid-responsive pancreatitides

Autoimmune pancreatitis has received considerable attention, especially due to the marked effect of corticosteroid therapy on its clinical course. Knowledge, especially regarding type 1 autoimmune pancreatitis, has significantly increased over the last decades, and despite significant differences in pathophysiology and outcomes, both type 1 and 2 autoimmune pancreatitis are still considered different types of the same disease. Some have proposed a different nomenclature reflecting these differences. Although the term steroid-responsive pancreatitides may be interpreted as synonymous to type 1 and 2 autoimmune pancreatitis, these are not the only pancreatic conditions that show a response to steroid therapy. Acute pancreatitis caused by vasculitis and connective tissue diseases and acute pancreatitis secondary to checkpoint inhibitors or programmed cell death receptor antibody-mediated blockage cancer therapy may also benefit from steroid treatment. This review presents current concepts on these disorders, aiming to increase awareness, analyze similarities and differences, and propose a new nomenclature that reflects their specific particularities, clustering them under the term “steroid-responsive pancreatitides”.

Lessons to be Learnt from Real-World Studies on Immune-Related Adverse Events with Checkpoint Inhibitors: A Clinical Perspective from Pharmacovigilance

The advent of immune checkpoint inhibitors (ICIs) caused a paradigm shift both in drug development and clinical practice; however, by virtue of their mechanism of action, the excessively activated immune system results in a multitude of off-target toxicities, the so-called immune-related adverse events (irAEs), requiring new skills for timely diagnosis and a multidisciplinary approach to successfully manage the patients. In the recent past, a plethora of large-scale pharmacovigilance analyses have characterized various irAEs in terms of spectrum and clinical features in the real world. This review aims to summarize and critically appraise the current landscape of pharmacovigilance studies, thus deriving take-home messages for oncologists. A brief primer to study design, conduction, and data interpretation is also offered. As of February 2020, 30 real-world postmarketing studies have characterized multiple irAEs through international spontaneous reporting systems, namely WHO Vigibase and the US FDA Adverse Event Reporting System. The majority of studies investigated a single irAE and provided new epidemiological evidence about class-specific patterns of irAEs (i.e. anti-cytotoxic T-lymphocyte antigen 4 [CTLA-4] versus anti-programmed cell death 1 [PD-1] receptor, and its ligand [PD-L1]), kinetics of appearance, co-occurrences (overlap) among irAEs, and fatality rate. Oncologists should be aware of both strengths and limitations of these pharmacovigilance analyses, especially in terms of data interpretation. Optimal management (including rechallenge), predictivity of irAEs (as potential biomarkers of effectiveness), and comparative safety of ICIs (also in terms of combination regimens) represent key research priorities for next-generation real-world studies.

On the use of immune checkpoint inhibitors in patients with viral infections including COVID-19

The present review summarizes up-to-date evidence addressing the frequently discussed clinical controversies regarding the use of immune checkpoint inhibitors (ICIs) in cancer patients with viral infections, including AIDS, hepatitis B and C, progressive multifocal leukoencephalopathy, influenza, and COVID-19. In detail, we provide available information on (1) safety regarding the risk of new infections, (2) effects on the outcome of pre-existing infections, (3) whether immunosuppressive drugs used to treat ICI-related adverse events affect the risk of infection or virulence of pre-existing infections, (4) whether the use of vaccines in ICI-treated patients is considered safe, and (5) whether there are beneficial effects of ICIs that even qualify them as a therapeutic approach for these viral infections.

Development and clinical applications of cancer immunotherapy against PD-1 signaling pathway

Dramatic advances in immune therapy have emerged as a promising strategy in cancer therapeutics. In addition to chemotherapy and radiotherapy, inhibitors targeting immune-checkpoint molecules such as cytotoxic T-lymphocyte antigen-4 (CTLA-4), programmed cell death receptor-1 (PD-1) and its ligand (PD-L1) demonstrate impressive clinical benefits in clinical trials. In this review, we present background information about therapies involving PD-1/PD-L1 blockade and provide an overview of current clinical trials. Furthermore, we present recent advances involving predictive biomarkers associated with positive therapeutic outcomes in cancer immunotherapy.