Frequency and imaging features of abdominal immune-related adverse events in metastatic lung cancer patients treated with PD-1 inhibitor

PD-1/PD-L1 inhibitor treatment and its impact on clinical imaging in non-small cell lung cancer: a systematic review and meta-analysis of immune-related adverse events

Background

In the contemporary era of cancer treatment, lung cancer (LC) holds the unenviable position of being the primary contributor to cancer-induced mortality worldwide. Although immunotherapy has expanded the therapeutic landscape for metastatic non-small cell lung cancer (NSCLC), the advent of immune checkpoint inhibitors has been accompanied by a concomitant increase in immune-related adverse events (irAEs). Timely detection of irAEs is pivotal for efficacious management and enhanced patient outcomes. Diagnostic imaging, encompassing x-ray and CT scans, can facilitate the identification and supervision of irAEs, thereby ensuring the prompt recognition of associated patterns and alterations for expeditious treatment.

Methods

The present inquiry undertook a systematic exploration of multiple databases, incorporating a diverse array of studies such as randomized controlled trials and observational analyses. Patient demographics, imaging outcomes, and risk of bias were extracted from the data. Meta-analysis was executed utilizing R Statistical Software, with the results of the risk of bias assessment summarized accordingly.

Findings

The analysis unveiled a higher prevalence of irAEs in patients receiving first-line treatment for NSCLC compared to those receiving subsequent treatments, with a statistically significant distinction observed for both high- and low-grade irAEs (p < 0.001). Pneumonitis, thyroiditis, and colitis emerged as the most frequently reported irAEs, whereas hepatitis and pancolitis were less commonly documented. This investigation signifies a crucial advancement in elucidating the function of imaging in the treatment of NSCLC with PD-1/PD-L1 inhibitors and emphasizes the imperative for ongoing research in this domain.

Immune checkpoint inhibitors-related pancreatitis with fulminant type 1 diabetes mellitus: case report and literature review

Immune checkpoint inhibitors (ICIs) are increasingly being used in the treatment of advanced human malignancies. ICIs-related adverse events, including pancreatitis and diabetes, have been individually characterized in the literature. The co-occurrence of ICIs-related pancreatitis with diabetes is rare and easily overlooked, but it is often severe or fatal. We present a patient with renal tumor resection who was treated with injection of the PD-L1 inhibitor toripalimab and eventually developed acute pancreatitis and fulminant type 1 diabetes mellitus. In addition, we conducted a literature review of ICIs-related pancreatitis with diabetes. The case in our report presented with paroxysmal abdominal pain and loss of appetite. Intravenous fluids and insulin infusion improved the patient's pancreatitis and explosive hyperglycemia. This article suggests that ICIs can affect endocrine and exocrine functions of the pancreas, while providing information and new perspectives for the diagnosis and treatment of this challenging rare disease, helping inspire clinicians for the early identification and effective management of similar cases.

Immune-Related Thyroiditis in Patients with Advanced Lung Cancer Treated with Immune Checkpoint Inhibitors: Imaging Features and Clinical Implications

Immune checkpoint inhibitors (ICI) are widely used in advanced nonsmall cell lung cancer (NSCLC) treatment, and the immune-related adverse events involving many organs have been recognized. This article investigated the incidence and imaging characteristics of immune-related thyroiditis in NSCLC patients and correlated the findings with clinical features. A total of 534 NSCLC patients treated with ICI were included. Imaging findings indicative of thyroiditis included changes in morphology and attenuation on restaging chest CT scans and FDG uptake on PET/CT during ICI therapy. Fifty patients (9.4%) had imaging findings indicative of thyroiditis. The median time to onset was 9.5 weeks (range: 0.9-87.4 weeks). The most common finding was diffuse hypoattenuation of the gland (72%), with enlargement in 15 and atrophy in 12 patients. Heterogeneous attenuation of the gland was noted in 12 patients (24%), with enlargement in 7 and atrophy in 1 patient. Two patients (4%) showed increased FDG uptake in the gland on PET/CT without changes in the CT scan. Twenty-two patients who had both clinical and radiologic diagnoses of thyroiditis were more frequently managed with hormone replacement than those with thyroiditis without an imaging abnormality (p < 0.0001). Therefore, awareness of the imaging findings of immune-related thyroiditis may alert clinicians to the presence of clinically relevant thyroiditis.

Imaging assessment of toxicity related to immune checkpoint inhibitors

In recent years, a wide range of cancer immunotherapies have been developed and have become increasingly important in cancer treatment across multiple oncologic diseases. In particular, immune checkpoint inhibitors (ICIs) offer promising options to improve patient outcomes. However, a major limitation of these treatments consists in the development of immune-related adverse events (irAEs) occurring in potentially any organ system and affecting up to 76% of the patients. The most frequent toxicities involve the skin, gastrointestinal tract, and endocrine system. Although mostly manageable, potentially life-threatening events, particularly due to neuro-, cardiac, and pulmonary toxicity, occur in up to 30% and 55% of the patients treated with ICI-monotherapy or -combination therapy, respectively. Imaging, in particular computed tomography (CT), magnetic resonance imaging (MRI), and 2-deoxy-2-[¹⁸F]fluoro-D-glucose positron emission tomography/computed tomography (¹⁸F-FDG-PET/CT), plays an important role in the detection and characterization of these irAEs. In some patients, irAEs can even be detected on imaging before the onset of clinical symptoms. In this context, it is particularly important to distinguish irAEs from true disease progression and specific immunotherapy related response patterns, such as pseudoprogression. In addition, there are irAEs which might be easily confused with other pathologies such as infection or metastasis. However, many imaging findings, such as in immune-related pneumonitis, are nonspecific. Thus, accurate diagnosis may be delayed underling the importance for adequate imaging features characterization in the appropriate clinical setting in order to provide timely and efficient patient management. ¹⁸F-FDG-PET/CT and radiomics have demonstrated to reliably detect these toxicities and potentially have predictive value for identifying patients at risk of developing irAEs. The purpose of this article is to provide a review of the main immunotherapy-related toxicities and discuss their characteristics on imaging.

Emerging Trends in Radionuclide Imaging of Infection and Inflammation in Pediatrics: Focus on FDG PET/CT and Immune Reactivity

The most common indication for ¹⁸F-FDG PET/CT is tumor imaging, which may be performed for initial diagnosis, staging, therapeutic response monitoring, surveillance, or suspected recurrence. In the routine practice of pediatric nuclear medicine, most infectious, inflammatory, and autoimmune processes that are detected on ¹⁸F-FDG PET/CT imaging - except for imaging in fever or inflammation of unknown origin - are coincidental and not the main indication for image acquisition. However, interpreting these "coincidental" findings is of utmost importance to avoid erroneously attributing these findings to a neoplastic process. We review the recent literature on fever of unknown origin as well as inflammation of unknown origin in pediatrics and then focus on the ¹⁸F FDG PET/CT imaging findings seen in two specific entities with increased immune reactivity: hemophagocytic lymphohistiocytosis syndrome and the immune-related adverse events associated with checkpoint inhibitors. We will subsequently close with two sections highlighting related topics and relevant references for further reading.

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.

Teaching cancer imaging in the era of precision medicine: Looking at the big picture

The role of imaging in cancer diagnosis and treatment has evolved at the same rapid pace as cancer management. Over the last twenty years, with the advancement of technology, oncology has become a multidisciplinary field that allows for researchers and clinicians not only to create individualized treatment options for cancer patients, but also to evaluate patients’ response to therapy with increasing precision. Familiarity with these concepts is a requisite for current and future radiologists, as cancer imaging studies represent a significant and growing component of any radiology practice, from tertiary cancer centers to community hospitals.

In this review we provide the framework to teach cancer imaging in the era of genomic oncology. After reading this article, readers should be able to illustrate the basics cancer genomics, modern cancer genomics, to summarize the types of systemic oncologic therapies available, their patterns of response and their adverse events, to discuss the role of imaging in oncologic clinical trials and the role of tumor response criteria and to display the future directions of oncologic imaging.

Harnessing big data to characterize immune-related adverse events

Immune-checkpoint inhibitors (ICIs) have transformed patient care in oncology but are associated with a unique spectrum of organ-specific inflammatory toxicities known as immune-related adverse events (irAEs). Given the expanding use of ICIs, an increasing number of patients with cancer experience irAEs, including severe irAEs. Proper diagnosis and management of irAEs are important to optimize the quality of life and long-term outcomes of patients receiving ICIs; however, owing to the substantial heterogeneity within irAEs, and despite multicentre initiatives, performing clinical studies of these toxicities with a sufficient cohort size is challenging. Pioneering studies from the past few years have demonstrated that aggregate clinical data, real-world data (such as data on pharmacovigilance or from electronic health records) and multi-omics data are alternative tools well suited to investigating the underlying mechanisms and clinical presentations of irAEs. In this Perspective, we summarize the advantages and shortcomings of different sources of 'big data' for the study of irAEs and highlight progress made using such data to identify biomarkers of irAE risk, evaluate associations between irAEs and therapeutic efficacy, and characterize the effects of demographic and anthropometric factors on irAE risk. Harnessing big data will accelerate research on irAEs and provide key insights that will improve the clinical management of patients receiving ICIs.

Response criteria for immunotherapy and the radiologic patterns of immune-related adverse events

Immunotherapy has revolutionized clinical outcomes in both early-stage and advanced-stage malignancies. Immunotherapy has improved patient survival in both solid and hematologic disorders with the potential added benefit of less toxicity compared to conventional cytotoxic chemotherapy. Imaging plays a fundamental role in monitoring treatment response and assessment of immune-related adverse events, e.g. pneumonitis, colitis, etc. Familiarity with the current strategies of immune-related response evaluation and their limitations is essential for radiologists to guide clinicians with their treatment decisions. Radiologists should be aware of the wide spectrum of immune-related adverse events and their various radiological features as well as the patterns of treatment response associated with immunotherapies.

Imaging evaluation of lung cancer treated with PD-1/PD-L1 inhibitors

Immunotherapy (PD-1/PD-L1 inhibitors) has attracted attention for lung cancer treatment and recasted the administration of immunotherapeutics to patients who have advanced/metastatic diseases. Whether in combination or as monotherapy, these medications have become common therapies for certain patients with lung cancer. Moreover, their usage is expected to expand widely in the future. This review aims to discuss the imaging evaluation of lung cancer response to PD-1/PD-L1 therapy with focus on new radiological criteria for immunotherapy response. Abnormal radiological responses (pseudoprogression, dissociative responses, and hyperprogression) and immune-related adverse events are also described.

Immune checkpoint inhibitor related adverse effects and FDG PET/CT findings

Immune check-point inhibitor (ICI) treatments activate the T-cells against tumor. Activated T-cells not only attack the tumor but also healthy cells, causing an autoimmune reaction in various tissues. These immune related adverse effects (IRAE) cause ¹⁸F-fluorodeoxyglucose (FDG) uptake in various tissues due to inflammation. It is important to recognize and report these findings on FDG Positron Emission Tomography/Computed Tomography (PET/CT) studies. FDG PET helps to determine the presence, location and severity of IRAEs. In severe cases, ICI treatments are interrupted or suspended and anti-inflammatory treatments are started. FDG uptake due IRAEs may mimic metastases or disease progression. Their presence may also help predicting response to treatment and have prognostic implications. In this review article, we will provide basic information about ICI treatments, IRAEs and FDG PET/CT findings.

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.

Immunotherapy-Related Imaging Findings in Patients with Gynecological Malignancies: What Radiologists Need to Know

Immunotherapy is an effective treatment option for gynecological malignancies. Radiologists dealing with gynecological patients undergoing treatment with immune checkpoint inhibitors should be aware of unconventional immune-related imaging features for the evaluation of tumor response and immune-related adverse events. In this paper, immune checkpoint inhibitors used for gynecological malignancies and their mechanisms of action are briefly presented. In the second part, patterns of pseudoprogression are illustrated, and different forms of immune-related adverse events are discussed.

CT, MRI and PET/CT features of abdominal manifestations of cutaneous melanoma: a review of current concepts in the era of tumor-specific therapies

Abdominal manifestations in patients with cutaneous melanoma include involvement due to metastatic spread and immune checkpoint inhibitor induced adverse events. The purpose of this review is to provide a critical overview of abdominal manifestations in patients with cutaneous melanoma and highlight the current imaging challenges in the era of tumor-specific therapies. Immune checkpoint inhibitors represent a treatment with demonstrated efficacy in the treatment of advanced cutaneous melanoma but are associated with several abdominal adverse events that must be recognized. CT has a role in the identification of colitis, enteritis and pancreatitis, whereas MRI has an important role in the diagnosis of autoimmune pancreatitis. Current evidence demonstrates that MRI should be the preferred imaging technique for the detection and characterization of hepatic and splenic metastases from cutaneous melanoma. The role of ¹⁸F-FDG-PET/CT should be further evaluated but current literature suggests an efficacy in the detection of pancreatic metastases not seen on CT and MRI.

Prognostic Value of Deep Learning-Mediated Treatment Monitoring in Lung Cancer Patients Receiving Immunotherapy

BACKGROUND

Checkpoint inhibitors provided sustained clinical benefit to metastatic lung cancer patients. Nonetheless, prognostic markers in metastatic settings are still under research. Imaging offers distinctive advantages, providing whole-body information non-invasively, while routinely available in most clinics. We hypothesized that more prognostic information can be extracted by employing artificial intelligence (AI) for treatment monitoring, superior to 2D tumor growth criteria.

METHODS

A cohort of 152 stage-IV non-small-cell lung cancer patients (NSCLC) (73 discovery, 79 test, 903CTs), who received nivolumab were retrospectively collected. We trained a neural network to identify morphological changes on chest CT acquired during patients' follow-ups. A classifier was employed to link imaging features learned by the network with overall survival.

RESULTS

Our results showed significant performance in the independent test set to predict 1-year overall survival from the date of image acquisition, with an average area under the curve (AUC) of 0.69 (p < 0.01), up to AUC 0.75 (p < 0.01) in the first 3 to 5 months of treatment, and 0.67 AUC (p = 0.01) for durable clinical benefit (6 months progression-free survival). We found the AI-derived survival score to be independent of clinical, radiological, PDL1, and histopathological factors. Visual analysis of AI-generated prognostic heatmaps revealed relative prognostic importance of morphological nodal changes in the mediastinum, supraclavicular, and hilar regions, lung and bone metastases, as well as pleural effusions, atelectasis, and consolidations.

CONCLUSIONS

Our results demonstrate that deep learning can quantify tumor- and non-tumor-related morphological changes important for prognostication on serial imaging. Further investigation should focus on the implementation of this technique beyond thoracic imaging.

Immunotherapy-Associated Pancreatic Adverse Events: Current Understanding of Their Mechanism, Diagnosis, and Management

Immune checkpoint inhibitors (ICIs) such as anti-programmed death-1 (PD-1) and its ligand PD-L1 and anti-cytotoxic T-lymphocyte antigen 4 (CTLA-4) monoclonal antibodies, are involved in T cell-mediated immune response augmentation and promote anti-tumor immunity. Cancer patients treated with combination of immunotherapy, chemotherapy, radiotherapy, and targeted therapy exhibit superior clinical outcomes and tolerance compared with patients treated with monotherapies. However, immutherapy is associated with several concomitant immune-related adverse events (irAEs). For instance, IrAEs interferes with function of gastrointestinal tract, endocrine, dermatological, nervous system and musculoskeletal systems. ICIs-associated pancreatic injury might causes decrease in endocrine and exocrine pancreatic function, resulting in metabolic and nutritional disorders. Clinicians who administer immune checkpoint inhibitors to cancer patients are diagnosed with hyperglycemia, abdominal pain and steatorrhea. Currently, the precise mechanism of ICIs-associated pancreatic injury has not been fully explored. This paper summarizes incidence, diagnosis, clinical characteristics, potential mechanisms, and treatment management patterns of ICIs-associated pancreatic AEs based on previous studies. In addition, possible management approaches of these adverse effects are presented in this paper. in the findings summarized in this paper lay a basis for management of ICIs-associated pancreatic AEs and expanding future immunotherapy applications.

Abdominal immune-related adverse events: detection on ultrasonography, CT, MRI and 18F-Fluorodeoxyglucose positron emission tomography

Immune checkpoint inhibitor and chimeric antigen receptor T-cell therapies are associated with a unique spectrum of complications termed immune-related adverse events (irAEs). The abdomen is the most frequent site of severe irAEs that require hospitalization with life-threatening consequences. Most abdominal irAEs such as enterocolitis, hepatitis, cholangiopathy, cholecystitis, pancreatitis, adrenalitis, and sarcoid-like reaction are initially detected on imaging such as ultrasonography (US), CT, MRI and fusion 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET)-CT during routine surveillance of cancer therapy. Early recognition and diagnosis of irAEs and immediate management with cessation of immune modulator cancer therapy and institution of immunosuppressive therapy are necessary to avert morbidity and mortality. Diagnosis of irAEs is confirmed by tissue sampling or by follow-up imaging demonstrating resolution. Abdominal radiologists reviewing imaging on patients being treated with anti-cancer immunomodulators should be familiar with the imaging manifestations of irAEs.

Gastrointestinal adverse events of immunotherapy

Cancer immunotherapy with immune-checkpoint inhibitors (ICIs) has emerged as an effective treatment for different types of cancer. ICIs are monoclonal antibodies that inhibit the signaling pathway that suppress antitumor T-cell activity. Patients benefit from increased overall and progression-free survival, but the enhancement of normal immunity can result in autoimmune manifestations, called immune-related adverse events (IRAEs), which may lead to a discontinuation of cancer therapy and to severe also life-threating events. IRAEs may affect any organs or system in the human body, being the gastrointestinal (GI) tract one of the most involved districts. Imaging plays an important role in recognizing GI IRAEs and radiologist should be familiar with the main spectrum of radiological appearance. Indeed, early detection of GI IRAEs is crucial for proper patient management and reduces morbidity and mortality. The purpose of this review is to present the most relevant imaging manifestation of GI IRAEs.

Imaging and clinical manifestations of immune checkpoint inhibitor-related colitis in cancer patients treated with monotherapy or combination therapy

PURPOSE

To determine the frequency, imaging, and clinical manifestations of immune checkpoint inhibitor (ICI)-related colitis in cancer patients on monotherapy or combination therapy.

METHODS

The electronic medical records of 1044 cancer patients who received ICIs were retrospectively reviewed to identify 48 patients who had a clinical diagnosis of immune-related colitis. Imaging studies were reviewed to identify patients with imaging manifestations of colitis. Demographic data, type of ICIs, symptoms, presence of other immune-related adverse events (irAEs), and management were recorded.

RESULTS

There was imaging evidence of immune-related colitis in 34 patients (24 men; median age: 63.5 years). The median time to onset of colitis was 75 days (IQR 25-75, 49.5-216 days) in patients receiving monotherapy (group 1) and 78 days (IQR 25-75, 44.3-99.5 days) in patients undergoing combination therapy (group 2) following start of ICI. Symptoms included diarrhea (91.1% [31 of 34]), nausea/vomiting (52.9% [18 of 34]), and abdominal pain (52.9% [18 of 34]). The most common imaging findings were bowel wall thickening (97% [33 of 34]) and fluid-filled colon (82.3% [28 of 34]). Colitis was diffuse in 21 of 34 (61.8%) patients. Imaging manifestations did not differ between the two groups (p > 0.05). Steroids and antibiotics were used to treat colitis in 29 of 34 (85.2%) and 13 of 34 (38.2%) patients, respectively. No patients in group 1 experienced concurrent irAEs, but 5 of 18 (27.8%) of patients in group 2 had other irAEs (p = 0.046).

CONCLUSION

Immune-related colitis occurred in 3.3% of patients receiving ICIs with bowel wall thickening, fluid-filled colon and pancolitis being the most common imaging manifestations. Imaging manifestations did not differ between patients receiving monotherapy or combination therapy. However, concurrent irAEs were significantly observed in patients undergoing combination therapy.

Immune-related adverse events on body CT in patients with small-cell lung cancer treated with immune-checkpoint inhibitors

PURPOSE

Investigate the incidence and imaging characteristics of radiologically-evident immune-related adverse events (irAEs) on body CT in patients with small-cell lung cancer (SCLC) treated with immune-checkpoint inhibitors.

METHODS

The study included 53 patients with relapsed/refractory SCLC (27 men, 26 women) treated with PD-1/PD-L1 inhibitors alone or in combination with CTLA-4 inhibition, who had baseline and at least one follow-up body CT during therapy. Body CT scans were reviewed to detect and characterize organ-specific irAEs including thyroiditis, pneumonitis, hepatitis, pancreatitis, enteritis, and colitis.

RESULTS

Nineteen patients (36 %) developed radiologically-evident irAEs. The median time from therapy initiation to irAE onset was 7.1 weeks. Pneumonitis and colitis were most common, noted in 9 patients (17 %) each. Seven colitis cases demonstrated pancolitis, and two cases showed segmental colitis associated with diverticulosis. The common radiographic patterns of pneumonitis were acute interstitial pneumonia (AIP)/acute respiratory distress syndrome (ARDS) pattern (n = 4) and cryptogenic organizing pneumonia (COP) pattern (n = 3). Other irAEs included thyroiditis (n = 3), enteritis (n = 2), hepatitis (n = 1), and pancreatitis (n = 1). Older age (p = 0.03) and prior radiotherapy to any organ (p = 0.03) was associated with overall irAEs. Prior chest radiotherapy was significantly associated with pneumonitis or thyroiditis (p = 0.0004).

CONCLUSION

Radiologically-evident irAEs were noted on body CT in 36 % of patients with SCLC treated with immune-checkpoint inhibitors. Colitis and pneumonitis were most common. Prior chest radiotherapy was a predictor of the development of both pneumonitis and thyroiditis. Awareness of risk factors and CT findings of irAEs is important for early detection and accurate diagnosis of potentially serious immunotherapy toxicities.

Management of Patients With Immune Checkpoint Inhibitor-Induced Enterocolitis: A Systematic Review

Immune checkpoint inhibitors (ICIs) have improved the treatment of several cancers. These drugs increase T-cell activity and the antitumor immune response but also have immune-related adverse effects that can affect the gastrointestinal (GI) tract. These adverse effects have been observed in 7% to 30% of patients treated with ICIs. As the number of diseases treated with ICIs increases, gastroenterologists will see more patients with ICI-induced GI adverse events. We performed a systematic review of the incidence, risk factors, clinical manifestations, and management of the adverse effects of ICIs on the GI tract. Treatment with anti-cytotoxic T-lymphocyte-associated antigen-4 often causes severe enterocolitis, whereas treatment with inhibitors of programmed cell death 1 have less frequent and more diverse adverse effects. Management of patients with GI adverse effects of ICIs should involve first ruling out other disorders, followed by assessment of severity, treatment with corticosteroids, and rapid introduction of infliximab therapy for nonresponders.

Update on Hodgkin lymphoma from a radiologist's perspective

Recent advances in the management of Hodgkin lymphoma, due to new staging and response assessment systems as well as new therapies, have redefined the role of imaging for this disease. The purpose of this article is to provide radiologists with an update on the current role of imaging in Hodgkin lymphoma from diagnosis to assessment of treatment response, in view of the new staging and response assessment system and current treatment strategies.

Imaging of Adverse Events Related to Checkpoint Inhibitor Therapy

Immunotherapy with checkpoint inhibitors (ICIs) is becoming standard of practice for an increasing number of cancer types. ICIs enhance T-cell action against the cancer cells. By unbalancing the immune system ICIs may cause dysimmune toxicities, a series of disorders broadly defined immune-related adverse events (irAEs). IrAEs may affect any organ or apparatus and most frequently involve skin, colon, endocrine organs, liver, and lungs. Early identification and appropriate treatment of irAEs can improve patient outcome. The paper aims at reviewing mechanisms of the occurrence of irAEs, the importance of a proper diagnosis and the main pillars of therapy. To provide effective guidance to the comprehension of major irAEs imaging findings will be reviewed.

Imaging of tumour response to immunotherapy

A wide range of cancer immunotherapy approaches has been developed including non-specific immune-stimulants such as cytokines, cancer vaccines, immune checkpoint inhibitors (ICIs), and adoptive T cell therapy. Among them, ICIs are the most commonly used and intensively studied. Since 2011, these drugs have received marketing authorisation for melanoma, lung, bladder, renal, and head and neck cancers, with remarkable and long-lasting treatment response in some patients. The novel mechanism of action of ICIs, with immune and T cell activation, leads to unusual patterns of response on imaging, with the advent of so-called pseudoprogression being more pronounced and frequently observed when compared to other anticancer therapies. Pseudoprogression, described in about 2–10% of patients treated with ICIs, corresponds to an increase of tumour burden and/or the appearance of new lesions due to infiltration by activated T cells before the disease responds to therapy. To overcome the limitation of response evaluation criteria in solid tumors (RECIST) to assess these specific changes, new imaging criteria—so-called immune-related response criteria and then immune-related RECIST (irRECIST)—were proposed. The major modification involved the inclusion of the measurements of new target lesions into disease assessments and the need for a 4-week re-assessment to confirm or not confirm progression. The RECIST working group introduced the new concept of “unconfirmed progression”, into the irRECIST. This paper reviews current immunotherapeutic approaches and summarises radiologic criteria to evaluate new patterns of response to immunotherapy. Furthermore, imaging features of immunotherapy-related adverse events and available predictive biomarkers of response are presented.

Nivolumab-induced adrenalitis

Immune checkpoint inhibitors (ICIs) are an evolving class of drugs for the treatment of various cancers; for example, their use is recommended as a second-line chemotherapy for non-small cell lung cancer. With the expanding use of ICIs, we are discovering their unique side effects, called immune-related adverse events (irAEs), which can impair gastrointestinal, hepatic, dermatological, endocrine and other systems. Nivolumab is an ICI that blocks the human programmed death receptor-1 (PD-1) on T cells to prevent the interaction between the receptor, PD-1, and human programmed death ligand-1 expressed on tumour cells. Here, we report a case of a 65-year-old woman with recurrent lung adenocarcinoma who was treated with nivolumab and developed immune-related adrenalitis, which was managed with hydrocortisone and fludrocortisone. This case highlights the importance of understanding the irAEs of ICIs to allow prompt recognition and management of life-threatening complications of the treatment.

Advanced urothelial cancer: a radiology update

The recent genomic characterization of urothelial carcinoma by the Cancer Genome Atlas Project, made possible by the introduction of high throughput, reduced cost, and sequence analysis, has shed new insights on the biology of advanced disease. In addition, studies on imaging of advanced urothelial carcinoma have widened the knowledge on disease presentation and on pattern of metastatic spread and their correlation with the underlying biology of urothelial carcinoma. The wide range of treatments for advanced urothelial cancer, including combined chemotherapy regimens and immune checkpoint inhibitors, each result in treatment class-specific patterns of response and adverse events. Results of studies point to the need for a reliable biomarker, perhaps with imaging, that predicts prognosis and treatment response to systemic treatment, and can be used to select the most effective treatment while minimizing toxicity. This review of advanced urothelial cancer introduces the latest advances in genetic profiling, the current role of imaging, the radiographic appearance of treatment response and their toxicities, and details potential future areas of imaging research.

Role of medical imaging for immune checkpoint blockade therapy: From response assessment to prognosis prediction

Immune checkpoint blockade (ICB) represents a promising approach in cancer therapy. Owing to the peculiar biologic mechanisms of anticancer activity, checkpoint blockers are accompanied with distinctive response patterns and toxicity profiles. Medical imaging is the cornerstone for response assessment to immunotherapy and plays a critical role in monitoring of immune-related adverse events (irAEs). Imaging-based biomarkers have shown tremendous potential for the prediction of therapeutic efficacies and clinical outcomes in patients treated with checkpoint inhibitors. In this article, the landscape of current response assessment systems for immunotherapy was reviewed with a special focus on the latest advances in the assessment of responses to ICB. Emerging imaging biomarkers were discussed along with the challenges regarding their clinical transformation. In addition, the biological mechanisms and clinical applications of ICB and irAEs were also within the scope of this review.

Imaging of Precision Therapy for Lung Cancer: Current State of the Art

Advances in characterization of molecular and genomic abnormalities specific to lung cancer have made precision therapy the current standard of care for lung cancer treatment. This article will provide a cutting-edge review of imaging of lung cancer in the current era of precision medicine. The focus of the article includes (a) an update on the recent advances in precision therapy for non-small cell lung cancer and their implications on imaging; (b) molecular and genomic biomarkers and pitfalls of image interpretations for lung cancer precision therapy; and (c) review of the current approaches and future directions of precision imaging for lung cancer, emphasizing emerging observations in longitudinal tumor kinetics, radiomics, and molecular and functional imaging. The article is designed to help radiologists to remain up to date in the rapidly evolving world of lung cancer therapy and serve as key members of multidisciplinary teams caring for these patients.