Immune Checkpoint Inhibitor Cancer Therapy: Spectrum of Imaging Findings

Splenic Pseudoprogression After CAR-T Therapy Detected by 18 F-FDG PET/CT in a Refractory Diffuse Large B-Cell Lymphoma Patient

ABSTRACT

A 43-year-old woman diagnosed with refractory diffuse large B-cell lymphoma was referred to chimeric antigen receptor T-cell therapy at our institution. After 3 cycles of bridging therapy, preinfusion 18 F-FDG PET/CT suggested a complete metabolic response. 18 F-FDG PET/CT 1 month after chimeric antigen receptor T-cell infusion showed 2 foci of elevated activity in the spleen, which was finally confirmed as pseudoprogression.

Tryptophan metabolism-related gene expression patterns: unveiling prognostic insights and immune landscapes in uveal melanoma

Uveal melanoma (UVM) remains the leading intraocular malignancy in adults, with a poor prognosis for those with metastatic disease. Tryptophan metabolism plays a pivotal role in influencing cancerous properties and modifying the tumor's immune microenvironment. In this study, we explore the relationship between tryptophan metabolism-related gene (TRMG) expression and the various features of UVM, including prognosis and tumor microenvironment. Our analysis included 143 patient samples sourced from public databases. Using K-means clustering, we categorized UVM patients into two distinct clusters. Further, we developed a prognostic model based on five essential genes, effectively distinguishing between low-risk and high-risk patients. This distinction underscores the importance of TRMGs in UVM prognostication. Combining TRMG data with gender to create nomograms demonstrated exceptional accuracy in predicting UVM patient outcomes. Moreover, our analysis reveals correlations between risk assessments and immune cell infiltrations. Notably, the low-risk group displayed a heightened potential response to immune checkpoint inhibitors. In conclusion, our findings underscore the dynamic relationship between TRMG expression and various UVM characteristics, presenting a novel prognostic framework centered on TRMGs. The deep connection between TRMGs and UVM's tumor immune microenvironment emphasizes the crucial role of tryptophan metabolism in shaping the immune landscape. Such understanding paves the way for designing targeted immunotherapy strategies for UVM patients.

Imaging Follow-Up of Nonsurgical Therapies for Lung Cancer: AJR Expert Panel Narrative Review

Lung cancer continues to be the most common cause of cancer-related death worldwide. In the past decade, with the implementation of lung cancer screening programs and advances in surgical and nonsurgical therapies, the survival of patients with lung cancer has increased, as has the number of imaging studies that these patients undergo. However, most patients with lung cancer do not undergo surgical re-section, because they have comorbid disease or lung cancer in an advanced stage at diagnosis. Nonsurgical therapies have continued to evolve with a growing range of systemic and targeted therapies, and there has been an associated evolution in the imaging findings encountered at follow-up examinations after such therapies (e.g., with respect to posttreatment changes, treatment complications, and recurrent tumor). This AJR Expert Panel Narrative Review describes the current status of nonsurgical therapies for lung cancer and their expected and unexpected imaging manifestations. The goal is to provide guidance to radiologists regarding imaging assessment after such therapies, focusing mainly on non-small cell lung cancer. Covered therapies include systemic therapy (conventional chemotherapy, targeted therapy, and immunotherapy), radiotherapy, and thermal ablation.

Efficacy and safety of preoperative immunotherapy alone followed by surgery in the treatment of advanced gastric cancer with MSI-H/dMMR or EBV-positive

BACKGROUND

At present, there is no consensus on whether preoperative immunotherapy (PIT) without chemotherapy followed by surgery could benefit patients with advanced gastric cancer (AGC). Here, we report a six-case series study to describe the safety and efficacy of PIT plus gastrectomy in patients with AGC.

METHODS

This study involved six patients with AGC who received PIT and surgery at our center between January 2019 and July 2021. Demographic characteristics, preoperative gastroscope biopsy pathology, surgical tissue pathology, radicalness of tumor resection, surgical safety, and recovery parameters were reported.

RESULTS

Six patients, including four patients with Epstein-Barr virus (EBV)-positive gastric cancer (GC) and two patients with microsatellite instability-high (MSI-H)/expression deficiency of mismatch repair (dMMR) protein GC, were enrolled in this study. Four patients experienced immunotherapy-related adverse events (irAEs), without severe adverse events (SAEs). Five patients underwent R0 resection, and one patient underwent palliative gastrectomy due to liver and hilar lymph node metastasis. Pathologic responses from the surgical tissue were observed in all patients, including two pathological complete response (pCR). No operative complications or postoperative deaths occurred. Three patients (50%) experienced mild or moderate postoperative complications without severe postoperative complications. All six patients eventually recovered and were discharged.

CONCLUSION

This study indicated that PIT was effective and tolerant in some patients with MSI-H/dMMR and/or EBV-positive AGC. PIT followed by gastrectomy might be an alternative treatment option for these selected patients.

Management of Non-Melanoma Skin Cancer: Radiologists Challenging and Risk Assessment

Basal cell carcinoma, squamous cell carcinoma, and Merkel cell carcinoma are the three main types of nonmelanoma skin cancers and their rates of occurrence and mortality have been steadily rising over the past few decades. For radiologists, it is still difficult to treat patients with advanced nonmelanoma skin cancer. Nonmelanoma skin cancer patients would benefit greatly from an improved diagnostic imaging-based risk stratification and staging method that takes into account patient characteristics. The risk is especially elevated among those who previously received systemic treatment or phototherapy. Systemic treatments, including biologic therapies and methotrexate (MTX), are effective in managing immune-mediated diseases; however, they may increase susceptibility to NMSC due to immunosuppression or other factors. Risk stratification and staging tools are crucial in treatment planning and prognostic evaluation. PET/CT appears more sensitive and superior to CT and MRI for nodal and distant metastasis as well as in surveillance after surgery. The patient treatment response improved with advent and utilization of immunotherapy and different immune-specific criteria are established to standardized evaluation criteria of clinical trials but none of them have been utilized routinely with immunotherapy. The advent of immunotherapy has also arisen new critical issues for radiologists, such as atypical response pattern, pseudo-progression, as well as immune-related adverse events that require early identification to optimize and improve patient prognosis and management. It is important for radiologists to have knowledge of the radiologic features site of the tumor, clinical stage, histological subtype, and any high-risk features to assess immunotherapy treatment response and immune-related adverse events.

The Interaction of Programmed Cell Death Protein and Its Ligands with Non-Coding RNAs in Neoplasms: Emerging Anticancer Immunotherapeutics

Recent studies have demonstrated that cancer cells can elude immune cells by creating a sanctuary within the tumor’s microenvironment. Large amounts of immune-suppressing signaling proteins can be expressed by cancer cells. One of the most important mechanisms in this system is immune suppression caused by tumors and the modulation of the immune checkpoint. The immune checkpoint is modulated by both the programmed cell death protein 1 (PD-1) and its ligands, programmed death ligand 1 (PD-L1) and PD-L2. Non-coding RNAs (ncRNA), including the more well-known microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs), all play roles in the regulation of biological processes and extensive diseases such as cancer. Thus, the focus of this study is on the interactions between the programmed death protein and its ligands with miRNAs, lncRNAs, and circRNAs during tumorigenesis and tumor progression. Furthermore, some FDA-approved drugs for the treatment of various cancers were based on their interactions with PD-1, PD-Ls, and ncRNAs. This promising strategy is still in the production stages, with additional results and clinical trials being processed.

Standardized classification schemes in reporting oncologic PET/CT

The imaging report is essential for the communication between physicians in patient care. The information it contains must be clear, concise with evidence-based conclusions and sufficient to support clinical decision-making. In recent years, several classification schemes and/or reporting guidelines for PET have been introduced. In this manuscript, we will review the classifications most frequently used in oncology for interpreting and reporting 18F-FDG PET imaging in lymphoma, multiple myeloma, melanoma and head and neck cancers, PSMA-ligand PET imaging for prostate cancer, and 68Ga-DOTA-peptide PET in neuroendocrine tumors (NET).

Immunotherapy Assessment: A New Paradigm for Radiologists

Immunotherapy denotes an exemplar change in an oncological setting. Despite the effective application of these treatments across a broad range of tumors, only a minority of patients have beneficial effects. The efficacy of immunotherapy is affected by several factors, including human immunity, which is strongly correlated to genetic features, such as intra-tumor heterogeneity. Classic imaging assessment, based on computed tomography (CT) or magnetic resonance imaging (MRI), which is useful for conventional treatments, has a limited role in immunotherapy. The reason is due to different patterns of response and/or progression during this kind of treatment which differs from those seen during other treatments, such as the possibility to assess the wide spectrum of immunotherapy-correlated toxic effects (ir-AEs) as soon as possible. In addition, considering the unusual response patterns, the limits of conventional response criteria and the necessity of using related immune-response criteria are clear. Radiomics analysis is a recent field of great interest in a radiological setting and recently it has grown the idea that we could identify patients who will be fit for this treatment or who will develop ir-AEs.

Nintedanib in an elderly non-small-cell lung cancer patient with severe steroid-refractory checkpoint inhibitor-related pneumonitis: A case report and literature review

Immune checkpoint inhibitors tremendously improve cancer prognosis; however, severe-grade immune-related adverse events may cause premature death. Current recommendations for checkpoint inhibitor-related pneumonitis (CIP) treatment are mainly about immunosuppressive therapy, and anti-fibrotic agents are also needed, especially for patients with poor response to corticosteroids and a longer pneumonitis course. This is because fibrotic changes play an important role in the pathological evolution of CIP. Here, we report a case demonstrating that nintedanib is a promising candidate drug for CIP management or prevention, as it has potent anti-fibrotic efficacy and a safety profile. Moreover, nintedanib could partially inhibit tumor growth in patients with non-small-cell lung cancer, and its efficacy can be improved in combination with other anti-tumor therapies.

Checkpoint Inhibitor Immune-Related Adverse Events: A Multimodality Pictorial Review

Cancer immunotherapies are drugs that modulate the body's own immune system as an anticancer strategy. Checkpoint inhibitor immunotherapies interfere with cell surface binding proteins that function to promote self-recognition and tolerance, ultimately leading to upregulation of the immune response. Given the striking success of these agents in early trials in melanoma and lung cancer, they have now been studied in many types of cancer and have become a pillar of anticancer therapy for many tumor types. However, abundant upregulation results in a new class of side effects, known as immune-related adverse events (IRAEs). It is critical for the practicing radiologist to be able to recognize these events to best contribute to care for patients on checkpoint inhibitor immunotherapy. Here, we provide a comprehensive system-based review of immune-related adverse events and associated imaging findings. Further, we detail the best imaging modalities for each as well as describe problem solving modalities. Given that IRAEs can be subclinical before becoming clinically apparent, radiologists may be the first provider to recognize them, providing an opportunity for early treatment. Awareness of IRAEs and how to best image them will prepare radiologists to make a meaningful contribution to patient care as part of the clinical team.

Successful Targeting of CTLA-4 in a Melanoma Clinical Case: A Long-Term "One Stop Therapeutic Shop"

The anti-Cytotoxic T-Lymphocyte Antigen 4 (CTLA-4) monoclonal antibody ipilimumab was the first in-class immune-checkpoint inhibitor (ICI) approved for the treatment of melanoma patients. Initially approved for metastatic cutaneous melanoma, treatment with ipilimumab subsequently demonstrated to significantly improve recurrence free survival (RFS) in fully resected, high-risk, stage III melanoma patients. Therapeutic use of ipilimumab has also allowed the initial identification and characterization of unconventional clinical and radiological patterns of response (ie, tumor flare, pseudo-progression) that may occur during ICI therapy, unlike chemotherapy or targeted therapy. As a result, the standard Response Evaluation Criteria In Solid Tumors (RECIST) and the World Health Organization (WHO) criteria conventionally utilized to assess responses to chemo/targeted therapy have been initially replaced by the immune-related (ir) Response Criteria (irRC) and then by the irRECIST, that encompass all patterns of response typical of ICI therapy, being key for the optimal comprehensive management of treated patients. Here, we report a paradigmatic clinical case of a long-term survival in a stage III melanoma patient, experiencing tumor flares during adjuvant treatment with ipilimumab, and an untreated disease relapse several years after ending therapy.

Safety and Efficacy of Dostarlimab in Patients With Recurrent/Advanced Non-small Cell Lung Cancer: Results from Cohort E of the Phase I GARNET Trial

BACKGROUND

Dostarlimab is an anti-programmed cell death protein-1 antibody being evaluated in recurrent/advanced solid tumors, including non-small cell lung cancer (NSCLC), in the ongoing Phase I, multi-center, open-label, 2-part (dose escalation and cohort expansion) GARNET study (NCT02715284).

MATERIALS AND METHODS

Here, we report an interim analysis of patients with recurrent/advanced NSCLC who progressed following platinum-based chemotherapy. Patients received dostarlimab (500 mg IV every 3 weeks [Q3W] for Cycles 1-4, then 1000 mg Q6W) until disease progression or unacceptable toxicity for > 2 years. The primary endpoints were immune-related objective response rate (irORR) per investigator-assessed irRECIST and safety.

RESULTS

As of 8, July 2019, 67 patients with recurrent/advanced NSCLC were enrolled and treated with dostarlimab; the majority had programmed death ligand 1 (PD-L1) tumor proportion score (TPS) < 1% (35.8% of patients) or PD-L1 TPS 1%-49% (29.9% of patients); 7.5% had PD-L1 TPS ≥ 50%, and 26.9% had unknown PD-L1 TPS status. Median follow-up was 13.8 months (range: 0.0-22.6). irORR was 26.9%, including 2 complete and 16 partial responses. The median duration of response of 11.6 months (range: 2.8-19.4). Responses were observed in 2 of 24 (16.7%) patients with PD-L1 TPS < 1%, 4 of 20 (20.0%) patients with PD-L1 TPS 1%-49% and 2 of 5 (40.0%) patients with PD-L1 TPS ≥ 50%. Fatigue (4.5%) was the most common Grade ≥ 3 treatment-related treatment-emergent adverse event (TRAE). Immune-related TRAEs (any grade) were observed in 28.4% of patients.

CONCLUSION

Dostarlimab demonstrated promising antitumor activity in advanced/recurrent NSCLC that progressed following platinum-based chemotherapy, including across all PD-L1 subgroups, and has an acceptable safety profile.

Imaging of Immune Checkpoint Inhibitor Immunotherapy for Non-Small Cell Lung Cancer

The normal immune system identifies and eliminates precancerous and cancerous cells. However, tumors can develop immune resistance mechanisms, one of which involves the exploitation of pathways, termed immune checkpoints, that normally suppress T-cell function. The goal of immune checkpoint inhibitor (ICI) immunotherapy is to boost T-cell-mediated immunity to mount a more effective attack on cancer cells. ICIs have changed the treatment landscape of advanced non-small cell lung cancer (NSCLC), and numerous ICIs have now been approved as first-line treatments for NSCLC by the U.S. Food and Drug Administration. ICIs can cause atypical response patterns such as pseudoprogression, whereby the tumor burden initially increases but then decreases. Therefore, response criteria have been developed specifically for patients receiving immunotherapy. Because ICIs activate the immune system, they can lead to inflammatory side effects, termed immune-related adverse events (irAEs). Usually occurring within weeks to months after the start of therapy, irAEs range from asymptomatic abnormal laboratory results to life-threatening conditions such as encephalitis, pneumonitis, myocarditis, hepatitis, and colitis. It is important to be aware of the imaging appearances of the various irAEs to avoid misinterpreting them as metastatic disease, progressive disease, or infection. The basic principles of ICI therapy; indications for ICI therapy in the setting of NSCLC; response assessment and atypical response patterns of ICI therapy, as compared with conventional chemotherapy; and the spectrum of irAEs seen at imaging are reviewed. An invited commentary by Nishino is available online. ^©RSNA, 2022.

Management of cutaneous melanoma: radiologists challenging and risk assessment

Melanoma patient remains a challenging for the radiologist, due to the difficulty related to the management of a patient more often in an advanced stage of the disease. It is necessary to determine a stratification of risk, optimizing the means, with diagnostic tools that should be optimized in relation to the type of patient, and improving knowledge. Staging and risk assessment procedures are determined by disease presentation at diagnosis. Melanoma staging is a critical tool to assist clinical decision-making and prognostic assessment. It is used for clinical trial design, eligibility, stratification, and analysis. The current standard for regional lymph nodes staging is represented by the sentinel lymph node excision biopsy procedure. For staging of distant metastases, PET-CT has the highest sensitivity and diagnostic odds ratio. Similar trend is observed during melanoma surveillance. The advent of immunotherapy, which has improved patient outcome, however, has determined new issues for radiologists, partly due to atypical response patterns, partly due to adverse reactions that must be identified as soon as possible for the correct management of the patient. The main objectives of the new ir-criteria are to standardize the assessment between different trials. However, these ir-criteria do not take into account all cases of atypical response patterns, as hyperprogression or dissociated responses. None of these criteria has actually been uniformly adopted in routine. The immune-related adverse events (irAEs) can involve various organs from head to toe. It is crucial for radiologists to know the imaging appearances of this condition, to exclude recurrent or progressive disease and for pneumonitis, since it could be potentially life-threatening toxicity, resulting in pneumonitis-related deaths in early phase trials, to allow a proper patient management.

PET-CT in Clinical Adult Oncology: II. Primary Thoracic and Breast Malignancies

Simple Summary

Positron emission tomography (PET), typically combined with computed tomography (CT), has become a critical advanced imaging technique in oncology. With PET-CT, a radioactive molecule (radiotracer) is injected in the bloodstream and localizes to sites of tumor because of specific cellular features of the tumor that accumulate the targeting radiotracer. The CT scan, performed at the same time, provides information to facilitate assessment of the amount of radioactivity from deep or dense structures, and to provide detailed anatomic information. PET-CT has a variety of applications in oncology, including staging, therapeutic response assessment, restaging, and surveillance. This series of six review articles provides an overview of the value, applications, and imaging and interpretive strategies of PET-CT in the more common adult malignancies. The second article in this series addresses the use of PET-CT in breast cancer and other primary thoracic malignancies.

Abstract

Positron emission tomography combined with x-ray computed tomography (PET-CT) is an advanced imaging modality with oncologic applications that include staging, therapy assessment, restaging, and surveillance. This six-part series of review articles provides practical information to providers and imaging professionals regarding the best use of PET-CT for the more common adult malignancies. The second article of this series addresses primary thoracic malignancy and breast cancer. For primary thoracic malignancy, the focus will be on lung cancer, malignant pleural mesothelioma, thymoma, and thymic carcinoma, with an emphasis on the use of FDG PET-CT. For breast cancer, the various histologic subtypes will be addressed, and will include ¹⁸F fluorodeoxyglucose (FDG), recently Food and Drug Administration (FDA)-approved ¹⁸F-fluoroestradiol (FES), and ¹⁸F sodium fluoride (NaF). The pitfalls and nuances of PET-CT in breast and primary thoracic malignancies and the imaging features that distinguish between subcategories of these tumors are addressed. This review will serve as a resource for the appropriate roles and limitations of PET-CT in the clinical management of patients with breast and primary thoracic malignancies for healthcare professionals caring for adult patients with these cancers. It also serves as a practical guide for imaging providers, including radiologists, nuclear medicine physicians, and their trainees.

Serial changes in liquid biopsy-derived variant allele frequency predict immune checkpoint inhibitor responsiveness in the pan-cancer setting

Major immunotherapy challenges include a limited number of predictive biomarkers and the unusual imaging features post-therapy, such as pseudo-progression, which denote immune infiltrate-mediated tumor enlargement. Such phenomena confound clinical decision-making, since the cancer may eventually regress, and the patient should stay on treatment. We prospectively evaluated serial, blood-derived cell-free DNA (cfDNA) (baseline and 2–3 weeks post-immune checkpoint inhibitors [ICIs]) for variant allele frequency (VAF) and blood tumor mutation burden (bTMB) changes (next-generation sequencing) (N = 84 evaluable patients, diverse cancers). Low vs. high cfDNA-derived average adjusted ΔVAF (calculated by a machine-learning model) was an independent predictor of higher clinical benefit rate (stable disease ≥6 months/complete/partial response) (69.2% vs. 22.5%), and longer median progression-free (10.1 vs. 2.25 months) and overall survival (not reached vs. 6.1 months) (all P < .001, multivariate). bTMB changes did not correlate with outcomes. Therefore, early dynamic changes in cfDNA-derived VAF were a powerful predictor of pan-cancer immunotherapy outcomes.

Liquid biopsy to predict immunotherapy response.

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.

Part 1: Imaging findings of common immune checkpoint inhibitor-related adverse effects

Over the last decade or so, immunotherapy and in particular immune checkpoint inhibitors have become common in the treatment of numerous cancers and have revolutionised oncology. The unique mechanisms of these agents has resulted in novel tumour response patterns and also new drug-related toxicities, both of which can have specific findings on imaging. The widespread and increasing use of these agents means these findings are now encountered across many radiology practices beyond just specialist oncology units. This pictorial essay aims to describe and illustrate imaging findings associated with common and important immune-related adverse events as a result of treatment with immune checkpoint inhibitors.

Thoracic Imaging Manifestations of Treated Lymphomas: Response Evaluation, Posttherapeutic Sequelae, and Complications

Lymphoma is the most common hematologic malignancy comprising a diverse group of neoplasms arising from multiple blood cell lineages. Any structure of the thorax may be involved at any stage of disease. Imaging has a central role in the initial staging, response assessment, and surveillance of lymphoma, and updated standardized assessment criteria are available to assist with imaging interpretation and reporting. Radiologists should be aware of the modern approaches to lymphoma treatment, the role of imaging in posttherapeutic surveillance, and manifestations of therapy-related complications.

Early 18F-FDG PET Flare-up Phenomenon After CAR T-Cell Therapy in Lymphoma

ABSTRACT

18F-FDG PET/CT imaging series were acquired on a 64-year-old woman with refractory diffuse large B lymphoma to monitor chimeric antigen receptor (CAR) T-cell therapy. Because of a clinical deterioration, 18F-FDG PET/CT performed 8 days after CAR T-cell therapy suggested an early flare-up phenomenon with new lymph node involvement, lymph node progression while a decrease in metabolic tumor volume. The 18F-FDG PET/CT 1 month after CAR T-cell therapy confirmed this hypothesis. Pseudoprogression in solid tumors treated by immunotherapy has generally been reported later after treatment.

Tumor Flare Reaction in a Classic Hodgkin Lymphoma Patient Treated With Brentuximab Vedotin and Tislelizumab: A Case Report

Background

Tumor flare reaction (TFR) is a clinical syndrome, which is mainly associated with painful and swollen lymph nodes or splenomegaly, slight fever, bone pain, and skin rash during treatment with immune-related drugs, causing difficulty in distinguishing TFR from disease progression. Brentuximab vedotin (BV) and programmed death 1 (PD-1) inhibitor are two ideal drugs used for the treatment of classic Hodgkin lymphoma, but few studies have reported their adverse effects in association with TFR. The efficacy and safety of monotherapy or combination therapy with these drugs needs to be further evaluated. It is essential to determine whether treated patients can develop TFR, thus enabling more accurate diagnosis and treatment.

Case presentation

A 26-year-old female patient, diagnosed with classic Hodgkin lymphoma, had received 2 + 3 cycles of ABVD chemotherapy (a combination of adriamycin, bleomycin, vinblastine, and dacarbazine) and 4 cycles of PD-1 inhibitor (tislelizumab) therapy but exhibited poor efficacy. Subsequently, she was given combination therapy of BV (100 mg) + tislelizumab (200 mg). However, a slight fever, painful and swollen axillary lymph nodes, multiple skin rashes with pruritus, joint pain, and fatigue with poor appetite appeared during the treatment. Ultrasound (US) scans revealed that multiple lymph nodes were significantly enlarged. After treatment with low-dose dexamethasone and cetirizine, the symptoms were alleviated. A biopsy of the left axillary lymph node revealed that lymphoid tissue exhibited proliferative changes, without tumor cell infiltration. These findings were consistent with the clinical and pathological manifestations of TFR.

Conclusion

Combination therapy with BV and PD-1 inhibitor was effective in the treatment of relapsed or refractory classic Hodgkin lymphoma. The results suggest that the combination therapy may cause TFR, and biopsy and also continuous imaging observation are important to determine the disease stage. This approach allows clinicians to decide whether to continue the current treatment plan, and alerts them to the occurrence of excessive activation of the immune system.

Pearls and Pitfalls in the Imaging of Targeted Therapy and Immunotherapy in Lung Cancer

Most lung cancers are diagnosed at advanced stage when the cancer has metastasized outside the lung. These patients are not eligible for curative surgery or radiation therapy and treated with systemic therapy. Advances in the understanding of the biology of lung cancer has resulted in the development of targeted therapy aimed at specific genetic mutations identified with non-small cell lung cancer and immunotherapy that helps the immune system recognize tumors as foreign, stimulates the immune system, and removes the inhibition that allows growth and spread of cancer cells. Tumors treated with targeted or immunotherapies respond differently when compared with traditional chemotherapy and not captured by conventional response criteria such as the World Health Organization criteria and Response Evaluation Criteria in Solid Tumors. Therefore, several modified criteria have been developed to appropriately address the treatment response when using these novel agents. Numerous treatment-related side effects have been described that are important to recognize to avoid misinterpretation as worsening tumor and to ensure appropriate management.

Impact of COVID-19 crisis on medical care of patients with metastasized uro-oncologic disease under systemic cancer therapy: a multicenter study in German university hospitals

Purpose

To date, over 4.2 million Germans and over 235 million people worldwide have been infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Uro-oncology (UO) patients are particularly vulnerable but in urgent need of life-saving systemic treatments. Our multicentric study examined the impact of the COVID-19 crisis on the medical care of UO patients in German university hospitals receiving ongoing systemic anti-cancer treatment and to detect the delay of medical care, defined as deferred medical treatment or deviation of the pre-defined follow-up assessment.

Methods

Data of 162 UO patients with metastatic disease undergoing systemic cancer treatment at five university hospitals in Germany were included in our analyses. The focus of interest was any delay or change in treatment between February 2020 and May 2020 (first wave of the COVID-19 crisis in Germany). Statistical analysis of contingency tables were performed using Pearson’s chi-squared and Fisher’s exact tests, respectively. Effect size was determined using Cramér’s V (V).

Results

Twenty-four of the 162 patients (14.8%) experienced a delay in systemic treatment of more than 2 weeks. Most of these received immuno-oncologic (IO) treatments (13/24, 54.2%, p = 0.746). Blood tests were delayed or canceled significantly more often in IO patients but with a small effect size (21.1%, p = 0.042, V = 0.230). Treatment of patients with renal cell carcinoma (12/73, 16.4%) and urothelial carcinoma (7/32, 21.9%) was affected the most.

Conclusions

Our data show that the COVID-19 pandemic impacted the medical care of UO patients, but deferment remained modest. There was a tendency towards delays in IO and ADT treatments in particular.

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.

Imaging biomarkers for evaluating tumor response: RECIST and beyond

Response Evaluation Criteria in Solid Tumors (RECIST) is the gold standard for assessment of treatment response in solid tumors. Morphologic change of tumor size evaluated by RECIST is often correlated with survival length and has been considered as a surrogate endpoint of therapeutic efficacy. However, the detection of morphologic change alone may not be sufficient for assessing response to new anti-cancer medication in all solid tumors. During the past fifteen years, several molecular-targeted therapies and immunotherapies have emerged in cancer treatment which work by disrupting signaling pathways and inhibited cell growth. Tumor necrosis or lack of tumor progression is associated with a good therapeutic response even in the absence of tumor shrinkage. Therefore, the use of unmodified RECIST criteria to estimate morphological changes of tumor alone may not be sufficient to estimate tumor response for these new anti-cancer drugs. Several studies have reported the low reliability of RECIST in evaluating treatment response in different tumors such as hepatocellular carcinoma, lung cancer, prostate cancer, brain glioma, bone metastasis, and lymphoma. There is an increased need for new medical imaging biomarkers, considering the changes in tumor viability, metabolic activity, and attenuation, which are related to early tumor response. Promising imaging techniques, beyond RECIST, include dynamic contrast-enhanced computed tomography (CT) or magnetic resonance imaging (MRI), diffusion-weight imaging (DWI), magnetic resonance spectroscopy (MRS), and ¹⁸ F-fluorodeoxyglucose (FDG) positron emission tomography (PET). This review outlines the current RECIST with their limitations and the new emerging concepts of imaging biomarkers in oncology.

Response Prediction and Evaluation Using PET in Patients with Solid Tumors Treated with Immunotherapy

Simple Summary

In cancer treatment, immunotherapy is increasingly becoming important as a component of first-line treatment and has improved the prognosis of patients since its introduction. A large group of patients, however, do not respond to immunotherapy, and predicting a treatment response remains challenging. Furthermore, evaluating a response using conventional computed tomography (CT) scans is not straightforward due to the different mechanism of action of immunotherapy compared to chemotherapy. This review provides an overview of positron emission tomography (PET) in predicting and evaluating treatment response to immunotherapy.

Abstract

In multiple malignancies, checkpoint inhibitor therapy has an established role in the first-line treatment setting. However, only a subset of patients benefit from checkpoint inhibition, and as a result, the field of biomarker research is active. Molecular imaging with the use of positron emission tomography (PET) is one of the biomarkers that is being studied. PET tracers such as conventional ¹⁸F-FDG but also PD-(L)1 directed tracers are being evaluated for their predictive power. Furthermore, the use of artificial intelligence is under evaluation for the purpose of response prediction. Response evaluation during checkpoint inhibitor therapy can be challenging due to the different response patterns that can be observed compared to traditional chemotherapy. The additional information provided by PET can potentially be of value to evaluate a response early after the start of treatment and provide the clinician with important information about the efficacy of immunotherapy. Furthermore, the use of PET to stratify between patients with a complete response and those with a residual disease can potentially guide clinicians to identify patients for which immunotherapy can be discontinued and patients for whom the treatment needs to be escalated. This review provides an overview of the use of positron emission tomography (PET) to predict and evaluate treatment response to immunotherapy.

Immune checkpoint inhibitors: current status

The use of immune checkpoint inhibitors (ICIs) is growing rapidly in oncology and palliative care clinicians and other generalists will increasingly see patients who are receiving, or who have received ICI. For optimal care, it is important that clinicians have a basic understanding of the unique nature of ICI as anticancer treatments, including patterns of response, potential issues with concurrent corticosteroid use and the wide range of possible immune-related adverse effects (IrAEs). This paper, informed by a recent literature search, provides a succinct yet comprehensive overview of ICI, with a particular focus on IrAE, highlighting that some are potentially life-threatening and/or can develop a long time, sometimes years, after even a short course of an ICI.

Imaging of the sellar and parasellar regions

Although a wide variety of pathologies can occur in the limited anatomic space within and surrounding the sella turcica only a few are common. This review aims to briefly summarize pituitary and parasellar anatomy and provide a focused description of the imaging features of both common and rare pituitary pathologies. Diagnoses of imaging findings with important implications for clinical management are highlighted. MR is the primary diagnostic modality for evaluation of this anatomic region. CT supplements MR in the evaluation of pathologies involving the bony sella turcica while angiography or nuclear medicine plays a limited clinical role. Despite the wide array of pathologies, imaging and basic clinical history will frequently yield a specific diagnosis or narrow differential. In certain pathologies such as hypophysitis or pituitary hyperplasia, proper imaging interpretation may obviate the need for surgical biopsy or resection. The two key elements to diagnosis in the pituitary region are localization of the abnormality and recognition of characteristic imaging features for different pathologies. Localization is particularly important in separating parasellar masses such as meningiomas, skull base tumors, carotid aneurysms, craniopharyngiomas, or sphenoid sinus tumors from pituitary masses. Imaging features are often variable and in some cases such as craniopharyngioma or epidermoid, can be almost pathognomonic. In cases of neoplastic pathology, imaging both provides diagnostic information and guides planning of surgical biopsy or resection. In most cases, biopsy or resection is performed though a trans-sphenoidal endoscopic route, and identifying invasion or the suprasellar cistern, skull base, or cavernous sinuses is critical.

Post-immunotherapy imaging in lung cancer

By boosting the immune system, immunotherapy with immune checkpoint inhibitors (ICIs) has altered the management of patients with various cancers including those with metastatic non-small cell lung cancer (NSCLC). As a result of immune system activation, ICIs are associated with unique response patterns (that are not addressed by traditional response criteria) and inflammatory side effects termed immune-related adverse events. In this article, we will review the role of immunotherapy in cancer treatment, specifically ICIs used in NSCLC treatment, radiological response criteria of immunotherapy, and the imaging spectrum of immune-related adverse events.

Multi-detector computed tomography (MDCT)-based severity score as a prognostic tool in patients with suspected immune checkpoint inhibitor therapy associated colitis

OBJECTIVE

This study aimed to assess MDCT as a diagnostic and prognostic tool in patients with suspected immune checkpoint inhibitor (ICI)-related colitis.

MATERIALS AND METHODS

This retrospective cohort study included patients receiving ICIs at three hospitals between 2015 and 2019 who underwent both abdominopelvic MDCT and endoscopic biopsy to workup suspected ICI-related colitis. Two radiologists independently reviewed MDCT images for signs of colitis based on pre-defined features. Diagnostic performance of MDCT was calculated and categorical variables between treatment subgroups were compared. Logistic regression was used to develop proposed MDCT criteria for diagnosis and MDCT severity score based on a combination of MDCT features of colitis to predict the patient outcomes in ICI-related colitis.

RESULTS

A total of 118 MDCT scans from 108 patients were evaluated for suspected colitis, with 72 confirmed ICI-related colitis cases. Sensitivity, specificity, PPV, and NPV of MDCT for diagnosis of ICI-related colitis was 81% (58/72), 52 % (24/46), 73% (58/80), and 63% (24/38), respectively. Small bowel involvement was visualized in 25% of cases with ICI-related colitis (18/72). In melanoma patients presenting with diarrhea grade ≥ 2 (n = 40), MDCT had the best diagnostic performance for ICI-related colitis (specificity = 80% [8/10], PPV = 92% [23/25]). MDCT severity scores predicted intravenous steroid use (OR 10.3, p = 0.004), length of stay > 7 days (OR 9.0, p < 0.001), and endoscopic mucosal ulceration (OR 4.7, p = 0.02).

CONCLUSION

MDCT is a useful diagnostic and prognostic tool for evaluating patients with immune checkpoint inhibitor-related colitis. An MDCT-based severity score enables assessment of disease severity and predicts outcome.

KEY POINTS

• MDCT is useful for the diagnosis of colitis in patients receiving immune checkpoint inhibitor (ICI) therapy, and an MDCT-based severity score allows for prognostication of patient outcomes. • MDCT yielded moderate sensitivity (81%) for diagnosis of ICI-related colitis but limited specificity (52%). However, in symptomatic melanoma patients (grade 2-4 diarrhea) with a high pretest probability, MDCT proved useful for diagnosis with a high PPV (92%). • For ICI-related colitis, our proposed MDCT severity score has prognostic value in predicting intravenous steroid use, prolonged length of stay during inpatient admission (> 7 days), and endoscopic mucosal ulceration.

Immune Checkpoint Inhibitor-Associated Pneumonitis in Non-Small Cell Lung Cancer: Current Understanding in Characteristics, Diagnosis, and Management

Immunotherapy that includes programmed cell death-1 (PD-1), programmed cell death- ligand 1 (PD-L1) and cytotoxic T lymphocyte antigen 4 (CTLA-4) inhibitors has revolutionized the therapeutic strategy in multiple malignancies. Although it has achieved significant breakthrough in advanced non-small cell lung cancer patients, immune-related adverse events (irAEs) including checkpoint inhibitor pneumonitis (CIP), are widely reported. As the particularly worrisome and potentially lethal form of irAEs, CIP should be attached more importance. Especially in non-small cell lung cancer (NSCLC) patients, the features of CIP may be more complicated on account of the overlapping respiratory signs compromised by primary tumor following immunotherapy. Herein, we included the previous relevant reports and comprehensively summarized the characteristics, diagnosis, and management of CIP. We also discussed the future direction of optimal steroid therapeutic schedule for patients with CIP in NSCLC based on the current evidence.

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.

Imaging Biomarkers to Predict and Evaluate the Effectiveness of Immunotherapy in Advanced Non-Small-Cell Lung Cancer

Objective

We aimed to identify imaging biomarkers to assess predictive capacity of radiomics nomogram regarding treatment response status (responder/non-responder) in patients with advanced NSCLC undergoing anti-PD1 immunotherapy.

Methods

197 eligible patients with histologically confirmed NSCLC were retrospectively enrolled from nine hospitals. We carried out a radiomics characterization from target lesions (TL) approach and largest target lesion (LL) approach on baseline and first follow-up (TP1) CT imaging data. Delta-radiomics feature was calculated as the relative net change in radiomics feature between baseline and TP1. Minimum Redundancy Maximum Relevance (mRMR) and Least Absolute Shrinkage and Selection Operator (LASSO) logistic regression were applied for feature selection and radiomics signature construction.

Results

Radiomics signature at baseline did not show significant predictive value regarding response status for LL approach (P = 0.10), nor in terms of TL approach (P = 0.27). A combined Delta-radiomics nomogram incorporating Delta-radiomics signature with clinical factor of distant metastasis for target lesions had satisfactory performance in distinguishing responders from non-responders with AUCs of 0.83 (95% CI: 0.75–0.91) and 0.81 (95% CI: 0.68–0.95) in the training and test sets respectively, which was comparable with that from LL approach (P = 0.92, P = 0.97). Among a subset of those patients with available pretreatment PD-L1 expression status (n = 66), models that incorporating Delta-radiomics features showed superior predictive accuracy than that of PD-L1 expression status alone (P <0.001).

Conclusion

Early response assessment using combined Delta-radiomics nomograms have potential advantages to identify patients that were more likely to benefit from immunotherapy, and help oncologists modify treatments tailored individually to each patient under therapy.

Early Evaluation of Immunotherapy Response in Lymphoma Patients by 18F-FDG PET/CT: A Literature Overview

Immunotherapy is a promising therapeutic strategy both for solid and hematologic tumors, such as in Hodgkin (HL) and non-Hodgkin lymphoma (NHL). In particular, immune-checkpoint inhibitors, such as nivolumab and pembrolizumab, are increasingly used for the treatment of refractory/relapsed HL. At the same time, evidence of chimeric antigen receptor (CAR)-T-cell immunotherapy efficacy mostly in NHL is growing. In this setting, the challenge is to identify an appropriate imaging method to evaluate immunotherapy response. The role of 18F-Fluorodeoxyglucose (18F-FDG) positron-emission tomography/computed tomography (PET/CT), especially in early evaluation, is under investigation in order to guide therapeutic strategies, taking into account the possible atypical responses (hyperprogression and pseudoprogression) and immune-related adverse events that could appear on PET images. Herein, we aimed to present a critical overview about the role of 18F-FDG PET/CT in evaluating treatment response to immunotherapy in lymphoma patients.

Non-contrast and portal venous phase computed tomography in breast cancer hepatic metastases: comparison of tumor measurements and impact on response assessment

Background

For many common malignancies, including breast cancer, evaluation for metastatic disease using multiphase computed tomography (CT) has fallen out of favor and been replaced by studies performed only in the portal venous phase. However, differences in tumor vascularity could produce differences in appearance on post-contrast imaging.

Purpose

To assess non-contrast phase and portal venous phase computed tomography in detection and measurement of hepatic metastases from breast carcinoma.

Materials and Methods

A total of 75 CT scans from 52 breast cancer patients were independently assessed by three body imagers for lesion presence, number and size. Readers randomly assessed portal venous phase or combined phase images at one session with cross-over reads performed four to six weeks later.

Results

In the 58% of cases where index lesions measured larger on combined phase, the mean difference in lesion size was 5.7 mm. In this group, combined phase reads demonstrated an 8.4 mm increase in sum of largest diameters, and a mean percentage sum of largest diameters increase of 19% compared to portal venous phase-only reads.

Conclusion

Addition of non-contrast phase images results in increased index lesion size in most patients with hepatic metastases from breast cancer. If only the portal venous phase is utilized, there is potential for incorrectly diagnosing disease progression on follow-up due to underestimation of lesion size.

Immune Checkpoint Inhibitor-Induced Pancreatic Injury: Imaging Findings and Literature Review

The immunotherapy revolution in cancer treatment involves a variety of specialists, not only oncologists, but also internal medicine physicians, endocrinologists, dermatologists, gastroenterologists, rheumatologists, and radiologists, introducing new scenarios and novel challenges in the diagnosis and management of a number of novel immune-related adverse events. Among these, immune checkpoint inhibitor-induced pancreatic injury has been described (occurring in up to 4% of patients) and has been reported to be responsible for visits to the emergency departments in up to 1.9% of patients treated with immune checkpoint inhibitors. This side effect can be symptomatic or non-symptomatic, and can be associated with the development of long-term damage to the pancreas, requiring the involvement of different specialists, including radiologists and gastroenterologists in the multidisciplinary team that manages these patients. The aim of this narrative review is to provide a summary of the available literature related to immune checkpoint inhibitor-induced pancreatic injury including the epidemiology, the clinical findings, and the management algorithm for diagnosis with a detailed analysis of the differential diagnosis at imaging, and treatment. A more in-depth focus is dedicated to symptomatic acute pancreatitis with its peculiar findings at imaging (ultrasound, computed tomography, and magnetic resonance imaging).

Are radiologists ready to evaluate true response to immunotherapy?

Background

Standardized response criteria for evaluating patients radiological imaging have an essential role in oncological management. Immunotherapy, using immune checkpoint inhibitors (ICIs), including drugs targeting cytotoxic T-lymphocyte-associated antigen 4 and programmed cell death protein 1 or its ligand, promise a new role that has demonstrated improvement management in cancers resistant to chemotherapy. This article reviews the literature to understand the most useful response evaluation criteria for optimal patient management under immunotherapy treatment. Areas that warrant further research are described.

Conclusion

In conclusion, ICIs have become more widely accepted and used by medical oncologists. Radiologists face challenges in assessing tumor response and becoming more involved in the management of treatment. The latest published immune-RECIST criteria can be used in response assessment, but further prospective evaluation is needed with registration clinical trials to be definitively validated.

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.

Treatment with pembrolizumab in programmed death ligand 1-positive recurrent glioblastoma: Results from the multicohort phase 1 KEYNOTE-028 trial

BACKGROUND

Current treatments for recurrent glioblastoma offer limited benefit. The authors report the antitumor activity and safety of the anti-programmed death 1 (anti-PD-1) immunotherapy, pembrolizumab, in programmed death ligand 1 (PD-L1)-positive, recurrent glioblastoma.

METHODS

Adult patients with PD-L1-positive tumors were enrolled in the recurrent glioblastoma cohort of the multicohort, phase 1b KEYNOTE-028 study (ClinicalTrials.gov identifier, NCT02054806) and received pembrolizumab 10 mg/kg every 2 weeks for up to 2 years. The primary endpoint was investigator-assessed overall response rate according to the Response Evaluation Criteria in Solid Tumors, version 1.1. Archival tumor samples were assessed for PD-L1 expression levels (prospectively) and T-cell-inflamed gene expression profile score (retrospectively).

RESULTS

After a median follow-up of 14 months (range, 2-55 months) among the 26 enrolled patients, the overall response rate was 8% (95% CI, 1%-26%). Two partial responses, lasting 8.3 and 22.8 months, occurred. Progression-free survival (median, 2.8 months; 95% CI, 1.9-8.1 months) rate at 6 months was 37.7%, and the overall survival (median, 13.1 months; 95% CI, 8.0-26.6 months) rate at 12 months was 58%. Correlation of therapeutic benefit to level of PD-L1 expression, gene expression profile score, or baseline steroid use could not be established. Treatment-related adverse events occurred in 19 patients (73%), and 5 patients experienced grade 3 or 4 events (there were no grade 5 events). Immune-mediated adverse events and infusion reactions occurred in 7 patients (27%).

CONCLUSIONS

Pembrolizumab monotherapy demonstrated durable antitumor activity in a subset of patients with manageable toxicity in this small, signal-finding, recurrent glioblastoma cohort. Future studies evaluating rationally designed pembrolizumab combination regimens may improve outcomes in patients with recurrent glioblastoma.

Thermal Ablation, Embolization, and Selective Internal Radiation Therapy Combined with Checkpoint Inhibitor Cancer Immunotherapy: Safety Analysis

PURPOSE

To describe interventional oncology therapies combined with immune checkpoint inhibitor (ICI) therapy targeting the programmed death 1 pathway in patients with different neoplasms.

MATERIALS AND METHODS

This was a retrospective cohort study of patients who underwent tumor-directed thermal ablation, embolization, or selective internal radiation therapy (SIRT) between January 1, 2011, and May 1, 2019, and received anti-programmed death 1/PD-L1 agents ≤ 90 days before or ≤ 30 days after the interventional procedure. Immune-related adverse events (irAEs) and procedural complications ≤ 90 days after the procedure were graded according to the Common Terminology Criteria for Adverse Events version 5.0. The study included 65 eligible patients (49% female; age 63 years ± 11.1). The most common tumors were metastatic melanoma (n = 28) and non-small cell lung cancer (NSCLC) (n = 12). Patients underwent 78 procedures (12 patients underwent > 1 procedure), most frequently SIRT (35.9%) and cryoablation (28.2%). The most common target organs were liver (46.2%), bone (24.4%), and lung (9.0%). Most patients received ICI monotherapy with pembrolizumab (n = 30), nivolumab (n = 22), and atezolizumab (n = 6); 7 patients received ipilimumab and nivolumab.

RESULTS

Seven (10.8%) patients experienced an irAE (71.4% grade 1-2), mostly affecting the skin. Median time to irAE was 33 days (interquartile range, 19-38 days). Five irAEs occurred in patients with melanoma, and no irAEs occurred in patients with NSCLC. Management required corticosteroids (n = 3) and immunotherapy discontinuation (n = 1); all irAEs resolved to grade ≤ 1. There were 4 intraprocedural and 32 postprocedural complications (77.8% grade < 3). No grade 5 irAEs and/or procedural complications occurred.

CONCLUSIONS

No unmanageable or unanticipated toxicities occurred within 90 days after interventional oncology therapies combined with ICIs.

Response evaluation after immunotherapy in NSCLC: Early response assessment using FDG PET/CT

The present study aimed to evaluate the role of early F-18 2-deoxy-2-[fluorine-18] fluoro-D-glucose positron emission tomography/computed tomography (FDG PET/CT) in non-small cell lung cancer patients undergoing immune checkpoint inhibitor (ICI) treatment.Twenty-four non-small cell lung cancer patients who received nivolumab or pembrolizumab and underwent FDG PET/CT as an interim analysis after 2 or 3 cycles of ICI treatment were retrospectively enrolled. Tumor response was assessed using the PET Response Criteria in Solid Tumors 1.0 (PERCIST) and the European Organization for Research and Treatment of Cancer (EORTC) criteria after 2 or 3 cycles of ICI treatment (SCAN-1) and after an additional 2 cycles of ICI treatment (SCAN-2). The best overall response was determined by FDG PET/CT or chest CT at ≥ 3 months after therapy initiation, and the clinical benefit was investigated. progression-free survival was investigated, and its correlation with clinicopathologic and metabolic parameters was examined using a Cox multivariate proportional hazards model.In the interim analysis, 4 patients achieved a complete metabolic response (CMR), 1 patient exhibited a partial metabolic response (PMR), and 14 patients had Progressive metabolic disease (PMD) according to the PERCIST and EORTC criteria. Four patients showed stable metabolic disease (SMD) according to the PERCIST criteria, and 2 patients showed different responses (i.e., PMR) according to the EORTC criteria. Patients with a CMR or PMR at SCAN-1 had a clinical benefit. Among the 4 patients with SMD at SCAN-1, only 1 experienced a clinical benefit regardless of the percent change in the peak standardized uptake value. Two patients with discordant response assessments between the PERCIST and EORTC criteria showed conflicting clinical benefits. Among the 14 patients with PMD, none experienced any clinical benefit. Only metabolic parameters were significant factors for predicting progression in the multivariate analysis (peak standardized uptake value and metabolic tumor volume, HRs of 1.18 and 1.00, respectively).Based on early F-18 FDG PET/CT after ICI treatment, metabolic parameters could predict post-treatment progression. Responses after ICI treatment were correctly assessed in patients with a CMR, a PMR, and PMD, but patients with SMD required a meticulous follow-up because of varying clinical benefits.

Locoregional Therapies for the Treatment of Uveal Melanoma Hepatic Metastases

Uveal melanoma is the most common primary intraocular malignant tumor in adults. Approximately 50% of patients develop metastatic disease of which greater than 90% of patients develop hepatic metastases. Following the development of liver tumors, overall survival is dismal with hepatic failure being the cause of death in nearly all cases. To prolong survival for patients with metastatic uveal melanoma, controlling the growth of hepatic tumors is essential. This article will discuss imaging surveillance following the diagnosis of primary uveal melanoma; locoregional therapies used to control the growth of hepatic metastases including chemoembolization, immunoembolization, radioembolization, percutaneous hepatic perfusion, and thermal ablation; as well as currently available systemic treatment options for metastatic uveal melanoma.

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.

Anticancer Effect of Salvia plebeia and Its Active Compound by Improving T-Cell Activity via Blockade of PD-1/PD-L1 Interaction in Humanized PD-1 Mouse Model

Immune checkpoint inhibitors, increasingly used to treat malignant tumors, are revolutionizing cancer treatment by improving the patient survival expectations. Despite the high antitumor efficacy of antibody therapeutics that bind to PD-1/PD-L1, study on small molecule-based PD-1/PD-L1 inhibitors is required to overcome the side effects of antibody therapeutics caused by their size and affinity. Herein, we investigated antitumor potential of Salvia plebeia R. Br. extract (SPE), which has been used as a traditional oriental medicine and food in many countries, and its components by the blockade of PD-1/PD-L1 interaction. SPE and its component cosmosiin effectively blocked the molecular interaction between PD-1 and PD-L1. SPE also inhibited tumor growth by increasing CD8+ T-cells in the tumor through the activation of tumor-specific T-cells in a humanized PD-1 mouse model bearing hPD-L1 knock-in MC38 colon adenocarcinoma tumor. This finding presents a preclinical strategy to develop small molecule-based anticancer drugs targeting the PD-1/PD-L1 immune checkpoint pathway.

Abdominal CT manifestations of adverse events to immunotherapy: a primer for radiologists

Immunotherapy is a rapidly growing field within oncology and is being increasingly used in the management of several malignancies. Due to their unique mechanism of action on the immune system and neoplastic cells, the response pattern and adverse events of this novel therapy are distinct from conventional systemic therapies. Accordingly, the imaging appearances following immunotherapy including adverse events are unique and at times perplexing. Imaging is integral to management of patients on immunotherapeutic agents and a thorough understanding of its mechanism, response patterns and adverse events is crucial for precise interpretation of imaging studies. This review provides a description of the mechanism of action of current immunotherapeutic agents and the organ-wise description of their side effects.

Monitoring von Immuntherapien

Hintergrund

Immuntherapien spielen in der Behandlung fortgeschrittener onkologischer Erkrankungen eine zunehmende Rolle. Bei einigen Patienten birgt die radiologische Diagnostik durch atypische, immuntherapieinduziete Therapieverläufe neue Herausforderungen.

Ziel der Arbeit

Dieser Beitrag soll einen Überblick über die bildgebenden Methoden des Monitorings von Immuntherapien geben, die assoziierten Phänomene Pseudoprogress und Hyperprogress erörtern sowie die Evaluationskriterien iRECIST vorstellen, welche sich als Evaluationsstandard für klinische Studien anbieten. Zusätzlich werden die radiologisch wichtigsten Nebenwirkungen und ihre bildmorphologischen Charakteristika beschrieben.

Material und Methoden

Für diesen Übersichtsartikel wurden Studienergebnisse und Reviews seit 2009 ausgewertet. Die Literaturrecherche erfolgte mittels PubMed, die Suchbegriffe enthielten „immunotherapy“, „checkpoint inhibitor“, „pseudoprogression“, „iRECIST“ und „immune related adverse events“.

Ergebnisse und Diskussion

Mit einer Inzidenz von bis zu 10 % ist der Pseudoprogress insgesamt selten; aktuell ist die Differenzierung von einem echten Progress nur durch eine Beobachtung des zeitlichen Verlaufs möglich. Die 2017 erschienenen iRECIST-Kriterien enthalten daher die neuen Kategorien unbestätigter (immune unconfirmed progressive disease iUPD) und bestätigter Progress (immune confirmed progressive disease iCPD). Bisher konnte keine evidenzbasierte Empfehlung bezüglich des Zeitintervalls zwischen den Untersuchungen gegeben werden. Als radiologisch wichtigste Nebenwirkungen sind die Hypophysitis und die Pneumonitis zu nennen. Letztere kann sich in verschiedenen Mustern der interstitiellen Pneumonie präsentieren. Die Differenzierung zwischen Pneumonitis, Infektion und Tumorprogress kann diagnostische Schwierigkeiten mit sich bringen.

Clinical, Imaging Findings, Responses, and Outcomes of Patients With Classical Hodgkin Lymphoma and Non-Hodgkin Lymphoma Undergoing Immune Checkpoint Inhibitor Therapy: A Single-Institution Experience

OBJECTIVE

The aim of the study was to study clinical, imaging findings, response patterns, and immune-related adverse events in classical Hodgkin lymphoma (cHL) and non-Hodgkin lymphoma (NHL) patients treated with immune checkpoint inhibitors (ICIs).

METHODS

A retrospective search was performed to identify patients with relapsed/refractory cHL and NHL treated with ICIs from 2015 to 2019. Clinical and laboratory data were collected. Imaging studies were reviewed for treatment response and immune-related adverse events.

RESULTS

Ten patients with relapsed/refractory cHL (median age, 41 years) and 14 patients with relapsed/refractory NHL (median age, 61 years) were identified. Overall response rate was 70% for cHL patients. None of the NHL patients demonstrated complete or partial response. One case of hyperprogression and one case with atypical response were radiologically detected in cHL patients. Hypothyroidism requiring treatment occurred in 2 (20%) of 10 cHL patients, one of which had imaging correlate. Of 14 NHL patients, 1 (7%) had radiologic evidence of pneumonitis and 1 (7%) had colitis.

CONCLUSIONS

This single-institution observational study demonstrated that overall response rate was higher in patients with cHL undergoing ICI. Immune checkpoint inhibitor therapy has unique response patterns and toxicities in both cHL and NHL patients that radiologists should keep in mind.