Thoracic Complications of Precision Cancer Therapies: A Practical Guide for Radiologists in the New Era of Cancer Care

Physiologically based pharmacokinetic model for predicting the biodistribution of albumin nanoparticles after induction and recovery from acute lung injury

The application of nanomedicine in the treatment of acute lung injury (ALI) has great potential for the development of new therapeutic strategies. To gain insight into the kinetics of nanocarrier distribution upon time-dependent changes in tissue permeability after ALI induction in mice, we developed a physiologically based pharmacokinetic model for albumin nanoparticles (ANP). The model was calibrated using data from mice treated with intraperitoneal LPS (6 mg/kg), followed by intravenous ANP (0.5 mg/mouse or about 20.8 mg/kg) at 0.5, 6, and 24 h. The simulation results reproduced the experimental observations and indicated that the accumulation of ANP in the lungs increased, reaching a peak 6 h after LPS injury, whereas it decreased in the liver, kidney, and spleen. The model predicted that LPS caused an immediate (within the first 30 min) dramatic increase in lung and kidney tissue permeability, whereas splenic tissue permeability gradually increased over 24 h after LPS injection. This information can be used to design new therapies targeting specific organs affected by bacterial infections and potentially by other inflammatory insults.

Pneumothorax in lung metastasis of advanced soft tissue sarcoma patients treated with oral pazopanib

AIM

Data on occurrence of pneumothorax after the use of oral pazopanib in advanced soft tissue sarcoma (STS) with lung metastases are scarce in literature. We aimed to evaluate those in our patients.

METHODS

This was a single center retrospective study of incidence of pneumothorax in patients with lung metastases in advanced STS treated with oral pazopanib between July, 2016 and December, 2020. Patients were treated with pazopanib usually from 2 nd line onwards with a dose ranging from 400 mg to 800 mg once daily.

RESULTS

Total of 34 patients with lung metastasis in a setting of advanced STS were treated with oral pazopanib during the study period. The setting of pazopanib use was 2 nd line in four and 1 st line in one of them. The starting dose was 600 mg once daily in three patients, 400 mg OD in one patient, and 800 mg OD in one patient. Five patients developed pneumothorax with duration on pazopanib of 6, 7, 24, 6, and 2.5 months, respectively. Three patients had symptoms and required chest tube drainage. None of them were smokers or had any other underlying lung disease. The disease response of those patients was stable disease in four and partial response in one during treatment with pazopanib. One patient had a rechallenge with further pazopanib course without any recurrence of pneumothorax.

CONCLUSIONS

Pneumothorax is a rare pulmonary complication after pazopanib use in patients with lung metastasis. Clinicians should be aware of this rare complication as literature is scarce. Rechallenge with pazopanib is feasible after pneumothorax.

Trastuzumab Deruxtecan‒Related Interstitial Lung Disease/Pneumonitis: Computed Tomography Imaging Patterns to Guide Diagnosis and Management

PURPOSE

Trastuzumab deruxtecan (T-DXd) is an antibody-drug conjugate approved for the treatment of several advanced cancers; however, severe or fatal interstitial lung disease/pneumonitis can occur. We characterized the computed tomography (CT) patterns of T-DXd‒related pneumonitis as a marker for its clinical severity.

MATERIALS AND METHODS

Ninety patients with advanced cancers who developed T-DXd‒related pneumonitis in two completed single-arm clinical trials were included. Three radiologists independently characterized the CT patterns of pneumonitis at diagnosis, for analyses of those patterns' relationships with clinical severity and pneumonitis outcome.

RESULTS

T-DXd‒related pneumonitis most commonly presented with cryptogenic organizing pneumonia (COP) pattern, observed in 65 patients (72%), followed by a newly identified COP/hypersensitivity pneumonitis (HP) pattern (13%), acute interstitial pneumonia (AIP)/acute respiratory distress syndrome (ARDS) pattern (11%), and HP pattern (3%). A subset of cases with COP pattern demonstrated an atypical distribution with upper and peripheral lung involvement (6/65; 9%). CT patterns were associated with Common Terminology Criteria for Adverse Events severity grades of pneumonitis, with the AIP/ARDS pattern having higher grades compared with others (P < .0001). Fatal pneumonitis was more common in the AIP/ARDS pattern than in others (P = .005). The onset of pneumonitis was earlier in the AIP/ARDS pattern compared with others (median time to onset: at 17.9 v 32.7 weeks of therapy; P = .019). Pneumonitis was treated by withholding T-DXd with or without corticosteroids in most patients (78/90; 87%).

CONCLUSION

T-DXd‒related pneumonitis most commonly demonstrated a COP pattern, with a subset having an atypical distribution. The AIP/ARDS pattern was indicative of severe, potentially fatal pneumonitis, and requires immediate clinical attention to mitigate serious adverse events.

Combined radiation- and immune checkpoint-inhibitor-induced pneumonitis – The challenge to predict and detect overlapping immune-related adverse effects from evolving laboratory biomarkers and clinical imaging

The risk of overlapping pulmonary toxicity induced by thoracic radio(chemo)therapy and immune checkpoint inhibitor therapy in the treatment of patients suffering from non-small cell lung cancer (NSCLC) is one important challenge in successful radioimmunotherapy. In the present opinion we highlight factors that we find important to be considered before treatment initiation, during the treatment sequence, and after treatment completion combined or sequential application of radio(chemo)therapy and immune checkpoint inhibitor therapy. A major aim is to optimize the therapeutic index and to avoid immune related adverse effects. The goals in the future will be focused not only on identifying patients already in the pretreatment phase who could benefit from this complex treatment, but also in identifying patients, who are most likely to have higher grade toxicity. In this respect, proper assessment of clinical performance status, monitoring for the presence of certain comorbidities, evaluation of laboratory parameters such as TGF-α and IL-6 levels, human leukocyte antigens (HLA), and consideration of other potential biomarkers which will evolve in near future are essential. Likewise, the critical parameters must be monitored during the treatment phase and follow-up care to detect potential side effects in time. With the help of high-end imaging which is already used on a daily basis in image guided radiotherapy (IGRT) for intensity modulated radiotherapy (IMRT), its advanced form volumetric modulated arc therapy (VMAT), and adaptive radiation therapy (ART), clinically relevant changes in lung tissue can be detected at an early stage of disease. Concurrent radiotherapy and immunotherapy requires a special focus on adverse events, particularly of the lung, but, when properly approached and applied, it may offer new perspectives for patients with locally advanced NSCLC to be seriously considered as a curative option.

Drug-induced lung disease: a brief update for radiologists

Pulmonary adverse events and drug-induced lung disease (DILD) can occur when treating many conditions. The incidence of DILDs in clinical practice and the variety of radiological findings have increased, mainly due to the increased use of novel therapeutic agents. It is crucial to determine whether the newly emerging clinical and imaging findings in these patients are due to the progression of the underlying disease, infection, pulmonary edema, or drug use, as this will change the patient management. Although the diagnosis of DILD is usually obtained by excluding other possible causes, radiologists should be aware of the imaging findings of DILD. This article reviews the essential radiological results of DILD and summarizes the critical clinical and imaging findings with an emphasis on novel therapeutic agents.

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.

Imaging of Drug-Related Pneumonitis in Oncology

Clinical applications of novel anticancer agents in the past few decades brought marked advances in cancer treatment, enabling remarkable efficacy and effectiveness; however, these novel agents are also associated with toxicities. Among various toxicities, drug-related pneumonitis is one of the major clinical challenges in the management of cancer patients. Imaging plays a key role in detection, diagnosis, and monitoring of drug-related pneumonitis during cancer treatment. In the current era of precision oncology, pneumonitis from molecular targeted therapy and immune-checkpoint inhibitors (ICI) has been recognized as an event of clinical significance. Additionally, further advances of therapeutic approaches in cancer have brought several emerging issues in diagnosis and monitoring of pneumonitis. This article will describe the computed tomography (CT) pattern-based approach for drug-related pneumonitis that has been utilized to describe the imaging manifestations of pneumonitis from novel cancer therapies. Then, we will discuss pneumonitis from representative agents of precision cancer therapy, including mammalian target of rapamycin inhibitors, epidermal growth factor receptor inhibitors, and ICI, focusing on the incidence, risk factors, and the spectrum of CT patterns. Finally, the article will address emerging challenges in the diagnosis and monitoring of pneumonitis, including pneumonitis from combination ICI and radiation therapy and from antibody conjugate therapy, as well as the overlapping imaging features of drug-related pneumonitis and coronavirus disease 2019 pneumonia. The review is designed to provide a practical overview of drug-related pneumonitis from cutting-edge cancer therapy with emphasis on the role of imaging.

Adverse effects under immune checkpoint inhibitors on [18F]FDG PET/CT imaging

Despite their undisputed contribution to the management of various tumors and the prolongation of patient survival, immune checkpoint inhibitors (ICIs) exert their effect at the cost of toxicity. In the context of the activation of the host immune system triggered by ICIs, collateral, inflammatory side effects, commonly addressed as immune-related adverse events (irAEs) often occur. Early detection of irAEs can be critical for adequate decisions on patient management that may subsequently improve patient outcome. Moreover, the emergence of irAEs has been linked with the antitumor effect elicited by ICIs, thus, their identification may potentially provide prognostic information. Although the diagnosis of irAEs is mainly clinical, some adverse events may be asymptomatic and only diagnosed by imaging modalities. At the same time, radiological signs of irAEs are not necessarily associated with clinical symptoms, however, clinicians should be alerted to their presence. Among imaging modalities [¹⁸F]FDG PET/CT has shown satisfying efficiency in response assessment and monitoring of ICIs' treatment, especially in patients suffering from metastatic melanoma and lung cancer. In this context, [¹⁸F]FDG PET/CT may also be a valuable method for surveillance of irAEs during immunotherapy. This article aims to review the most common adverse events observed on [¹⁸F]FDG PET/CT under immunotherapy and summarize potential results linking PET signs of irAEs with response assessment to ICIs.

Part 2: Imaging findings of uncommon but important immune checkpoint inhibitor-related adverse effects

Oncology care has significantly changed with the emergence of immunotherapy agents, in particular immune checkpoint inhibitors (ICIs). This has had an immediate effect on imaging, with different radiological tumour responses to treatment compared with conventional chemotherapies, and novel imaging findings due to complications caused by these agents (referred to as immune-related adverse effects, irAEs). Some of the more common irAEs may be familiar, but as the use of ICIs increases to a wider variety of cancers, these complications, and in particular, the less common irAEs, will be encountered more frequently on imaging. It will be increasingly important to be familiar with these uncommon irAEs, particularly since they can be difficult to recognise and distinguish from metastatic disease. The aim of this pictorial essay was to describe and illustrate imaging findings that may be encountered related to uncommon but important irAEs as a result of treatment with immune checkpoint inhibitors.

Moderne Tumortherapien und ihre pulmonalen Nebenwirkungen

Die Strahlentherapie und in jüngerer Zeit insbesondere die medikamentöse molekulare Therapie sind zentrale Bestandteile der modernen Onkologie. Beide Therapieformen eignen sich dazu, Tumoren bei vergleichsweise geringen systemischen Nebenwirkungen effektiv zu behandeln. Dennoch haben auch diese Behandlungsansätze Nebenwirkungen, die zum einen durch die Toxizität der Strahlung, zum anderen durch immunmodulatorische Effekte der verabreichten Medikamente ausgelöst werden. Das pneumotoxische Potenzial dieser Therapieformen spiegelt sich unter anderem in der Entstehung von interstitiellen Pneumonitiden wider, die in fibrotische Lungengerüstveränderungen übergehen können. Erschwert wird die klinische Diagnose der Erkrankung durch die unspezifischen Symptome. Die Computertomographie (CT) stellt ein ausgezeichnetes Mittel dar, um korrespondierende Verdichtungen zu diagnostizieren und im zeitlichen Verlauf zu monitoren. Damit wird dem Radiologen im interdisziplinären Kontext eine wichtige Rolle bei der Diagnostik dieses Krankheitsbildes zuteil.

Side Effects of Oncologic Treatment in the Chest: Manifestations at FDG PET/CT

Fluorodeoxyglucose (FDG) PET/CT is a vital imaging technique used for staging, assessing treatment response, and restaging following completion of therapy in patients who are undergoing or have completed oncologic treatment. A variety of adverse effects from chemotherapy, targeted therapy, immunotherapy, and radiation therapy are commonly encountered in oncologic patients. It is important to be aware of the manifestations of these adverse effects seen on FDG PET/CT images to avoid misinterpreting these findings as disease progression. Furthermore, early identification of these complications is important, as it may significantly affect patient management and even lead to a change in treatment strategy. The authors focus on the FDG PET/CT manifestations of a broad spectrum of oncologic therapy-related adverse effects in the thorax, as well as some treatment-related changes that may potentially mimic malignancy. Online supplemental material is available for this article. ^©RSNA, 2021.

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.

Pulmonary Toxicities Associated With the Use of Immune Checkpoint Inhibitors: An Update From the Immuno-Oncology Subgroup of the Neutropenia, Infection & Myelosuppression Study Group of the Multinational Association for Supportive Care in Cancer

The development of immune checkpoint inhibitors (ICIs) has revolutionized cancer treatment, with agents such as nivolumab, pembrolizumab, and cemiplimab targeting programmed cell death protein-1 (PD-1) and durvalumab, avelumab, and atezolizumab targeting PD-ligand 1 (PD-L1). Ipilimumab targets cytotoxic T lymphocyte-associated antigen-4 (CTLA-4). These inhibitors have shown remarkable efficacy in melanoma, lung cancer, urothelial cancer, and a variety of solid tumors, either as single agents or in combination with other anticancer modalities. Additional indications are continuing to evolve. Checkpoint inhibitors are associated with less toxicity when compared to chemotherapy. These agents enhance the antitumor immune response and produce side- effects known as immune-related adverse events (irAEs). Although the incidence of immune checkpoint inhibitor pneumonitis (ICI-Pneumonitis) is relatively low, this complication is likely to cause the delay or cessation of immunotherapy and, in severe cases, may be associated with treatment-related mortality. The primary mechanism of ICI-Pneumonitis remains unclear, but it is believed to be associated with the immune dysregulation caused by ICIs. The development of irAEs may be related to increased T cell activity against cross-antigens expressed in tumor and normal tissues. Treatment with ICIs is associated with an increased number of activated alveolar T cells and reduced activity of the anti-inflammatory Treg phenotype, leading to dysregulation of T cell activity. This review discusses the pathogenesis of alveolar pneumonitis and the incidence, diagnosis, and clinical management of pulmonary toxicity, as well as the pulmonary complications of ICIs, either as monotherapy or in combination with other anticancer modalities, such as thoracic radiotherapy.

[Modern tumor therapy and its pulmonary side effects]

Die Strahlentherapie und in jüngerer Zeit insbesondere die medikamentöse molekulare Therapie sind zentrale Bestandteile der modernen Onkologie. Beide Therapieformen eignen sich dazu, Tumoren bei vergleichsweise geringen systemischen Nebenwirkungen effektiv zu behandeln. Dennoch haben auch diese Behandlungsansätze Nebenwirkungen, die zum einen durch die Toxizität der Strahlung, zum anderen durch immunmodulatorische Effekte der verabreichten Medikamente ausgelöst werden. Das pneumotoxische Potenzial dieser Therapieformen spiegelt sich unter anderem in der Entstehung von interstitiellen Pneumonitiden wider, die in fibrotische Lungengerüstveränderungen übergehen können. Erschwert wird die klinische Diagnose der Erkrankung durch die unspezifischen Symptome. Die Computertomographie (CT) stellt ein ausgezeichnetes Mittel dar, um korrespondierende Verdichtungen zu diagnostizieren und im zeitlichen Verlauf zu monitoren. Damit wird dem Radiologen im interdisziplinären Kontext eine wichtige Rolle bei der Diagnostik dieses Krankheitsbildes zuteil.

Safety and Feasibility of Cryoablation during Immunotherapy in Patients with Metastatic Soft Tissue Sarcoma

PURPOSE

Patients with metastatic soft tissue sarcoma (STS) undergo a wide array of treatments, including surgery, radiation, chemotherapy, immunotherapy, and ablative therapies, to control their disease. The combination of cryoablation and immunotherapy may lead to an enhanced antitumor immune response via the abscopal effect. It is hypothesized that the combination of cryoablation and immunotherapy in patients with metastatic STS is safe and feasible.

MATERIALS AND METHODS

A single-center retrospective analysis was performed on patients with metastatic STS who underwent cryoablation. Sixteen patients were treated with 27 cryoablation procedures while receiving ipilimumab and nivolumab from April 2017 to July 2020. Response Evaluation Criteria in Solid Tumors, 1.1, were used to determine the outcomes of nontarget tumors. Progression-free survival (PFS) and overall survival (OS) were calculated from the date of the first cryoablation after initiating immunotherapy until progression or death.

RESULTS

Thirty-four tumors were cryoablated, 23 of which were intentionally subtotal. The most common tumor subtype was liposarcoma (n = 4). Thirteen (81%) patients had previously demonstrated disease progression on multiple lines of chemotherapy. All tumors cryoablated with a complete intention demonstrated a complete response. Seven patients had a clinical benefit, including 1 with a complete response, 1 with a partial response, and 5 with stable disease. The median OS was 14.1 months, with a median PFS of 2.3 months (95% confidence interval, 1.8-14.3). Five patients had pneumothoraces after cryoablation, 2 of whom required chest tube placement. Eleven patients experienced adverse events related to immunotherapy, 10 of whom experienced grade 1 or 2.

CONCLUSIONS

Cryoablation in patients with metastatic STS undergoing immunotherapy is feasible and safe.

Immune checkpoint inhibitor-associated sarcoidosis: A usually benign disease that does not require immunotherapy discontinuation

OBJECTIVE

To analyse the clinical patterns of sarcoidosis triggered by immune checkpoint inhibitors (ICIs) in patients with cancer.

PATIENTS AND METHODS

The ImmunoCancer International Registry is a big data-sharing multidisciplinary network from 18 countries dedicated to evaluating the clinical research of immune-related adverse events related to cancer immunotherapies.

RESULTS

We identified 32 patients with biopsy-proven sarcoidosis. Underlying cancer included mainly melanoma (n = 24). Cancer immunotherapy consisted of monotherapy in 19 cases (anti-PD-1 in 18 and ipilimumab in 1) or combined ipilimumab + nivolumab in 13. The time median interval between initiation of ICI and sarcoidosis diagnosis was 3 months (range, 2-29 months). The use of combined ICI was associated with a shorter delay in developing sarcoidosis symptoms. The disease was symptomatic in 19 (59%) cases with mostly cutaneous, respiratory and general symptoms. The organs involved included mainly the mediastinal lymph nodes (n = 32), the lungs (n = 11), the skin (n = 10) and the eyes (n = 5). Pulmonary computed tomography studies showed bilateral hilar lymphadenopathy in all cases. There was no severe manifestation. Specific systemic therapy was required in only 12 patients (37%): oral glucocorticoids in 9, and hydroxychloroquine in 3. ICIs were held in 25 patients (78%) and definitively discontinued in 18 (56%) patients. Seven patients continued ICI treatment with a second flare in one case. In six additional patients, an ICI was reintroduced with no harm, and sarcoidosis relapsed in one of them.

CONCLUSION

Our study shows that ICI-related sarcoidosis seems to have a specific profile, possibly more benign than that of idiopathic sarcoidosis, and does not necessarily imply ICI discontinuation.

Immune checkpoint inhibitors: An emergency medicine focused review

INTRODUCTION

Several novel cancer therapies have been developed, many of which focused on immune system modulation. These include immune checkpoint inhibitors, modulators, T-cell therapy, monoclonal antibodies, cytokines, oncolytic viruses, and vaccines. Although many of these therapies are well tolerated, significant adverse reactions can occur as a result of these novel drugs.

OBJECTIVE

This narrative review discusses complications associated with immune based cancer therapies, specifically immune checkpoint inhibitors, for emergency clinicians.

DISCUSSION

Novel cancer therapies including immune checkpoint inhibitors can improve the care of patients with malignancy. However, these therapies have a number of potential complications, known as immune-related adverse events (irAEs). Complications can involve the neurologic, cardiac, pulmonary, dermatologic, renal, gastrointestinal, hepatic, and hematologic systems. IrAEs most commonly occur in the first several months following treatment initiation. These complications can be graded based on severity of clinical and laboratory findings. While most of these irAEs are mild, patients may present with critical illness. Treatment commonly includes immune checkpoint inhibitor discontinuation, steroids, and evaluation for other immunosuppressant medications.

CONCLUSIONS

Knowledge of this novel cancer therapy class and its potential complications can improve the care of patients on immune checkpoint inhibitors in the emergency department setting.

Everolimus-induced pneumonitis in neuroendocrine neoplasms: correlation of CT findings and clinical signs

BACKGROUND

Everolimus, a mammalian target of rapamycin (mTOR)-inhibitor, is approved for the treatment of advanced neuroendocrine neoplasms (NEN). A rare major adverse event is the occurrence of drug-induced pneumonitis.

PURPOSE

To evaluate the correlation between clinical signs and computed tomography (CT) findings in everolimus-induced pneumonitis in patients with NEN.

MATERIAL AND METHODS

Ninety patients with NEN treated with everolimus were retrospectively enrolled (approved by our Institutional Review Board). All patients received chest CTs before the initiation of everolimus and during the treatment along with physical examinations. Clinical signs of pneumonitis were scored (symptomatic score) according to CTCAE v5.0. Pulmonary function tests (PFT) were evaluated if available. CT images were analyzed based on the severity of interstitial lung disease (ILD), the overall pneumonitis extent (PnE), and regarding presence of typical lung opacification patterns. Follow-up examinations of patients with pneumonitis were analyzed.

RESULTS

Pneumonitis was diagnosed in 18 (20%) patients. There was no significant correlation between symptomatic score or PFT and ILD score or PnE. In case of a cryptogenic organizing pneumonia pattern (n = 14), symptomatic scores were significantly lower (P = 0.035) than in case of other opacification patterns (n = 4). In the follow-up analysis, we could identify four different clinical courses.

CONCLUSION

CT detects everolimus-induced pneumonitis at a subclinical stage. In this setting, CT findings, clinical severity, and PFT do not clearly correlate. Opacification pattern analysis seems to be of importance when assessing the severity of CT findings. Asymptomatic patients with positive CT findings should be closely monitored to timely initiate specific treatment.

Case 286: Sarcoidlike Granulomatosis and Lymphadenopathy-Thoracic Manifestations of Nivolumab Drug Toxicity

History A 70-year-old man had a posterior left thigh lesion confirmed to be biopsy-proven melanoma. The patient underwent wide excision and sentinel node biopsy, which showed absence of residual melanoma. Two years later, the patient noticed a subcentimeter subcutaneous lump in his thigh. Repeat excisional biopsy showed involvement of the surrounding soft tissue, consistent with a satellite lesion. Follow-up combined PET/CT revealed satellite nodules around the primary lesion, enabling confirmation of subcutaneous metastatic disease. The patient was subsequently started on nivolumab, an anti-programmed cell death 1 (PD-1) immune checkpoint inhibitor that blocks PD-1 and is approved as a first-line treatment in patients with advanced metastatic melanoma. On the baseline scan prior to starting nivolumab, there were no CT findings that suggested metastatic disease, nor were there enlarged mediastinal or hilar lymph nodes. Five months after initiation of nivolumab treatment, the first follow-up chest CT scan was performed and showed new findings in the mediastinum and bilateral lungs. The patient remained asymptomatic during the treatment period. Furthermore, the subcutaneous metastatic disease remained stable during the treatment period, and no other site of metastatic disease was noted on follow-up CT scans obtained during the first 5 months of treatment. The patient had no prior history of infectious or occupational exposures. During the nivolumab treatment cycle, his pertinent laboratory values and physical examination findings were unremarkable.

Comparison of Chest CT Findings of COVID-19, Influenza, and Organizing Pneumonia: A Multireader Study

Background: Previous studies have compared CT findings of COVID-19 pneumonia with those of other infections; however, to our knowledge, no studies have included non-infectious organizing pneumonia (OP) as a comparison group. Objective: To compare chest CT features of COVID-19, influenza, and OP using a multireader design, and to assess radiologists' performance in distinguishing between these conditions. Methods: This retrospective study included 150 chest CT examinations in 150 patients (mean age 58±16 years) with diagnosis of COVID-19, influenza, or non-infectious OP (50 randomly selected abnormal CT examinations per diagnosis). Six thoracic radiologists independently assessed CT examinations for 14 individual CT findings and Radiologic Society of North America (RSNA) COVID-19 category and recorded a favored diagnosis. CT characteristics of the three diagnoses were compared using random effects models; readers' diagnostic performance was assessed. Results: COVID-19 pneumonia was significantly different (p<.05) from influenza pneumonia for seven of 14 chest CT findings, though different (p<.05) from OP for 4 of 14 findings [central or diffuse distribution in 10% and 7% of COVID-19 vs 20% and 21% of OP; unilateral distribution in 1% of COVID-19 vs 7% of OP; non-tree-in-bud nodules in 32% of COVID-19 vs 53% of OP; tree-in-bud nodules in 6% of COVID-19 vs 14% of OP]. A total of 70% of cases of COVID-19, 33% of influenza, and 47% of OP had an RSNA COVID-19 category of typical (p<.001). Mean percentage of correct favored diagnoses compared to actual diagnoses was 44% for COVID-19, 29% for influenza, and 39% for OP. Mean diagnostic accuracy of favored diagnoses was 70% for COVID-19 pneumonia and 68% for both influenza and OP. Conclusion: CT findings of COVID-19 substantially overlap with influenza and, to a greater extent, with OP. Radiologists' diagnostic accuracy was low in a study sample containing equal proportions of these three types of pneumonia. Clinical Impact: Recognized challenges in diagnosing COVID-19 by CT are furthered by our observed strong overlap between CT appearances of COVID-19 and OP. This challenge may be particularly evident in clinical settings with substantial proportions of patients with potential causes of OP such as ongoing cancer therapy or autoimmune conditions.

Secondary pneumothorax during immunotherapy in two patients with metastatic solid tumors; a new entity

Background: We present two cases of secondary pneumothorax after immunotherapy in two different clinics. Case summary: A 25-year old female patient with metastatic osteosarcoma, treated with atezolizumab. Grade 2 pneumonitis developed twice in the first year. Treatment was continued after recovery and areas of pneumonitis and pneumothorax were observed on computed tomography. No other reason could be found to cause pneumothorax. Pneumothorax resorbed spontaneously during follow-up. A 36-year old female patient treated with nivolumab for metastatic renal cell carcinoma (RCC), areas of pneumonitis and pneumothorax were only found as the cause of dyspnea. After treatment, remission was achieved on computed tomography findings. Pneumothorax was detected for the second time during continued therapy, and immunotherapy stopped permanently. Conclusion: These cases, indicate that immunotherapy can cause secondary immune-related pneumothorax based on immune pneumonitis.

Drug-Related Pneumonitis in Cancer Treatment during the COVID-19 Era

Interstitial lung disease is recognized as a group of diseases with a different etiopathogenesis characterized by chronic lung inflammation with the accumulation of inflammatory cells, lymphocytes and macrophages, and the consequent release of proinflammatory cytokines. Various degrees of pulmonary fibrosis can be associated with this inflammatory condition. Interstitial lung disease related to oncological drugs is a relevant problem in clinical practice. The etiopathogenetic mechanisms underlying this adverse event are not completely known but can be partly explained by the mechanism of action of the drug involved. Therefore, knowledge of the relevance of this potentially fatal adverse event supported by the reported safety data of pivotal studies becomes fundamental in the management of patients. The prompt diagnosis of drug-related pneumonia and the consequent differential diagnosis with other forms of pneumonia allow a rapid suspension of treatment and the establishment of an immunosuppressive treatment if necessary. In the context of the health emergency related to SARS CoV2 infection and COVID-19-related interstitial lung disease, such knowledge holds decisive relevance in the conscious choice of cancer treatments. Our intent was to describe the oncological drugs most correlated with this adverse event by reporting, where possible, the percentages of insurgency in pivotal studies to provide an overview and therefore promote greater awareness of this important toxicity related to oncological treatment.

Imaging of Oncologic Treatment-Related Pneumonitis: A Focused Review on Emerging Issues of Immune Checkpoint Inhibitor Pneumonitis, From the AJR Special Series on Inflammation

Treatment-related pneumonitis represents a major challenge in oncology patients undergoing therapy, and imaging plays an essential role in detection, diagnosis, and monitoring of pneumonitis in these patients. Among various types of pneumonitis from different kinds of cancer treatments, immune checkpoint inhibitor (ICI)-related pneumonitis has been recognized as an important topic in the radiology and oncology communities since 2015, given the increasing clinical indications for ICI therapy in patients with cancer. Moreover, clinical applications of ICIs continue to advance rapidly with novel combination approaches, leading to further emerging challenges. This focused review describes the current knowledge about ICI pneumonitis and discusses several newly emerging issues involving recurrence and flare of ICI pneumonitis, as well as involving pneumonitis from new combination approaches including ICI with epidermal growth factor receptor (EGFR) inhibitors and ICI with radiotherapy. The article concludes with a summary of unmet needs in the care of patients with ICI pneumonitis as well as of future directions in the advancement of knowledge about ICI pneumonitis and patient care for ICI pneumonitis. Given the proven multifaceted value of imaging in ICI pneumonitis, radiologists will remain central in the ongoing multidisciplinary journey to further understand and overcome this challenging toxicity for patients with cancer.

Chest CT Diagnosis and Clinical Management of Drug-related Pneumonitis in Patients Receiving Molecular Targeting Agents and Immune Checkpoint Inhibitors: A Position Paper from the Fleischner Society

Use of molecular targeting agents and immune checkpoint inhibitors (ICIs) has increased the frequency and broadened the spectrum of lung toxicity, particularly in patients with cancer. The diagnosis of drug-related pneumonitis (DRP) is usually achieved by excluding other potential known causes. Awareness of the incidence and risk factors for DRP is becoming increasingly important. The severity of symptoms associated with DRP may range from mild or none to life-threatening with rapid progression to death. Imaging features of DRP should be assessed in consideration of the distribution of lung parenchymal abnormalities (radiologic pattern approach). The CT patterns reflect acute (diffuse alveolar damage) interstitial pneumonia and transient (simple pulmonary eosinophilia) lung abnormality, subacute interstitial disease (organizing pneumonia and hypersensitivity pneumonitis), and chronic interstitial disease (nonspecific interstitial pneumonia). A single drug can be associated with multiple radiologic patterns. Treatment of a patient suspected of having DRP generally consists of drug discontinuation, immunosuppressive therapy, or both, along with supportive measures eventually including supplemental oxygen and intensive care. In this position paper, the authors provide diagnostic criteria and management recommendations for DRP that should be of interest to radiologists, clinicians, clinical trialists, and trial sponsors, among others. This article is a simultaneous joint publication in Radiology and CHEST. The articles are identical except for stylistic changes in keeping with each journal's style. Either version may be used in citing this article. Published under a CC BY 4.0 license. Online supplemental material is available for this article.

Chest CT Diagnosis and Clinical Management of Drug-Related Pneumonitis in Patients Receiving Molecular Targeting Agents and Immune Checkpoint Inhibitors: A Position Paper From the Fleischner Society

Use of molecular targeting agents and immune checkpoint inhibitors (ICIs) has increased the frequency and broadened the spectrum of lung toxicity, particularly in patients with cancer. The diagnosis of drug-related pneumonitis (DRP) is usually achieved by excluding other potential known causes. Awareness of the incidence and risk factors for DRP is becoming increasingly important. The severity of symptoms associated with DRP may range from mild or none to life-threatening with rapid progression to death. Imaging features of DRP should be assessed in consideration of the distribution of lung parenchymal abnormalities (radiologic pattern approach). The CT patterns reflect acute (diffuse alveolar damage) interstitial pneumonia and transient (simple pulmonary eosinophilia) lung abnormality, subacute interstitial disease (organizing pneumonia and hypersensitivity pneumonitis), and chronic interstitial disease (nonspecific interstitial pneumonia). A single drug can be associated with multiple radiologic patterns. Treatment of a patient suspected of having DRP generally consists of drug discontinuation, immunosuppressive therapy, or both, along with supportive measures eventually including supplemental oxygen and intensive care. In this position paper, the authors provide diagnostic criteria and management recommendations for DRP that should be of interest to radiologists, clinicians, clinical trialists, and trial sponsors, among others.

Clinical course and prognosis of patients with lung cancer who develop anticancer therapy-related pneumonitis

BACKGROUND

Pneumonitis can be triggered by anti-cancer therapies: cytotoxic chemotherapy, tyrosine kinase inhibitors, and immune checkpoint inhibitors. There are few treatment options for patients who develop such pneumonitis and their treatment including chemotherapy is generally difficult thus would limit patient's prognosis. In this study, we investigated the clinical course of patients with lung cancer who developed anti-cancer therapy-related pneumonitis.

PATIENTS AND METHODS

We retrospectively examined data of patients who had developed pneumonitis triggered by anti-cancer agents and required hospitalization from January 2014 to March 2019 and analyzed their subsequent clinical course and prognosis.

RESULTS

The median age of the 58 study patients was 68 years and 82.8% were men. The median interval between first receiving the responsible agent and drug-induced pneumonitis was 7.4 weeks. Approximately 38% of patients were subsequently able to receive some anti-cancer therapy. The median post-pneumonitis overall survival (OS) from commencement of anti-cancer treatment was 13.2 months. No significant differences were found in survival time between treatment agents. However, patients who received some anticancer therapy after pneumonitis had significantly longer survival times than those did not (HR = 4.11, p = 0.0003) and patients who took longer to develop pneumonitis had a longer survival (HR = 2.28, p = 0.0148). Multivariate analysis revealed that short interval to onset and no post-pneumonitis anticancer therapy were independent predictors of short survival.

CONCLUSION

Although patients who developed pneumonitis had relatively short survival times, the interval between initial therapy and pneumonitis had survival impact. Survival can be prolonged by administering further cancer treatment after resolution of pneumonitis.

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.

Differentiation of COVID-19 Pneumonitis and ICI Induced Pneumonitis

Immune checkpoint inhibitors (ICI) have become the standard of care treatment for several tumor types. ICI-induced pneumonitis is a serious complication seen with treatment with these agents. Cancer has been reported to be one of the risk factors for severe coronavirus disease 2019 (COVID-19) caused by infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), that has engulfed the world in the last couple of months. In patients with cancer treated with ICI who present at the emergency department with respiratory symptoms during the COVID-19 pandemic, correct diagnosis can be challenging. Symptoms and radiological features of ICI pneumonitis can be overlapping with those of COVID-19 related pneumonia. For the latter, dexamethasone and remdesivir have shown encouraging results, while vaccines are currently being evaluated in phase III trials. The mainstay of treatment in ICI pneumonitis is immunosuppressive therapy, as this is a potentially fatal adverse event. It has been speculated that immunosuppression may be associated with increased risk of progression to severe COVID-19, especially during the early stage of infection with SARS-CoV-2. Therefore, distinction between these two entities is warranted. We summarize the clinical, radiological features as well as additional investigations of both entities, and suggest a diagnostic algorithm for distinction between the two. This algorithm may be a supportive tool for clinicians to diagnose the underlying cause of the pneumonitis in patients treated with ICI during this COVID-19 pandemic.

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.

A Review of the Mechanisms and Clinical Implications of Precision Cancer Therapy-Related Toxicity: A Primer for the Radiologist

OBJECTIVE. The purpose of this review is to elucidate the mechanisms, types, and clinical significance of molecular targeted therapy (MTT) and immune checkpoint inhibitors (ICIs) and their related toxicity, emphasizing the radiologic manifestations. CONCLUSION. The related toxicities of MTT and ICIs can have acute, recurrent, chronic, and delayed presentations. These toxicities may serve as markers of response and survival. By understanding the clinical significance of drug toxicities, radiologists can play an important role in personalized cancer therapy.

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.

A multidisciplinary consensus on the morphological and functional responses to immunotherapy treatment

The implementation of immunotherapy has radically changed the treatment of oncological patients. Currently, immunotherapy is indicated in the treatment of patients with head and neck tumors, melanoma, lung cancer, bladder tumors, colon cancer, cervical cancer, breast cancer, Merkel cell carcinoma, liver cancer, leukemia and lymphomas. However, its efficacy is restricted to a limited number of cases. The challenge is, therefore, to identify which subset of patients would benefit from immunotherapy. To this end, the establishment of immunotherapy response criteria and predictive and prognostic biomarkers is of paramount interest. In this report, a group of experts of the Spanish Society of Medical Oncology (SEOM), the Spanish Society of Medical Radiology (SERAM), and Spanish Society of Nuclear Medicine and Molecular Imaging (SEMNIM) provide an up-to-date review and a consensus guide on these issues.

Immune-related (IR)-pneumonitis during the COVID-19 pandemic: multidisciplinary recommendations for diagnosis and management

Immune-related (IR)-pneumonitis is a rare and potentially fatal toxicity of anti-PD(L)1 immunotherapy. Expert guidelines for the diagnosis and management of IR-pneumonitis include multidisciplinary input from medical oncology, pulmonary medicine, infectious disease, and radiology specialists. Severe acute respiratory syndrome coronavirus 2 is a recently recognized respiratory virus that is responsible for causing the COVID-19 global pandemic. Symptoms and imaging findings from IR-pneumonitis and COVID-19 pneumonia can be similar, and early COVID-19 viral testing may yield false negative results, complicating the diagnosis and management of both entities. Herein, we present a set of multidisciplinary consensus recommendations for the diagnosis and management of IR-pneumonitis in the setting of COVID-19 including: (1) isolation procedures, (2) recommended imaging and interpretation, (3) adaptations to invasive testing, (4) adaptations to the management of IR-pneumonitis, (5) immunosuppression for steroid-refractory IR-pneumonitis, and (6) management of suspected concurrent IR-pneumonitis and COVID-19 infection. There is an emerging need for the adaptation of expert guidelines for IR-pneumonitis in the setting of the global COVID-19 pandemic. We propose a multidisciplinary consensus on this topic, in this position paper.

Rheumatic Manifestations in Patients Treated with Immune Checkpoint Inhibitors

Immune checkpoint inhibitors (ICIs) are monoclonal antibodies that activate the immune system, aiming at enhancing antitumor immunity. Their clinical efficacy is well-documented, but the side effects associated with their use are still under investigation. These drugs cause several immune-related adverse events (ir-AEs), some of which stand within the field of rheumatology. Herein, we present a literature review performed in an effort to evaluate all publicly available clinical data regarding rheumatic manifestations associated with ICIs. The most common musculoskeletal ir-AEs are inflammatory arthritis, polymyalgia rheumatica and myositis. Non-musculoskeletal rheumatic manifestations are less frequent, with the most prominent being sicca, vasculitides and sarcoidosis. Cases of systemic lupus erythematosus or scleroderma are extremely rare. The majority of musculoskeletal ir-AEs are of mild/moderate severity and can be managed with steroids with no need for ICI discontinuation. In severe cases, more intense immunosuppressive therapy and permanent ICI discontinuation may be employed. Oncologists should periodically screen patients receiving ICIs for new-onset inflammatory musculoskeletal complaints and seek a rheumatology consultation in cases of persisting symptoms.

Radiographic patterns of symptomatic radiation pneumonitis in lung cancer patients: Imaging predictors for clinical severity and outcome

OBJECTIVE

Investigate the spectrum of radiographic patterns of radiation pneumonitis (RP) in lung cancer patients and identify imaging markers for high-grade RP and RP-related death.

METHODS

Eighty-two patients with lung cancer treated with conventional chest radiotherapy who had symptomatic RP were identified from the radiation oncology database. The imaging features of RP were studied for association with high-grade RP (Grade ≥3) and RP-related death (Grade 5).

RESULTS

RP was Grade 2 in 60 (73%), Grade 3 in 15 (18%), and Grade 5 in 7 patients (9%). Lower performance status (p = 0.04), squamous cell histology (p = 0.03), and FEV1 ≤ 2 (p = 0.009) were associated with high-grade pneumonitis. Older age (p = 0.03) and squamous cell histology (p = 0.03) were associated with RP-related death. The CT findings included ground-glass and reticular opacities in all patients, with traction bronchiectasis in 77 (94%) and consolidation in 74 (90%). The most common radiographic pattern of RP was cryptogenic organizing pneumonia (COP) pattern (n = 54), followed by acute interstitial pneumonia (AIP)/acute respiratory distress syndrome (ARDS) pattern (n = 10). Higher extent of lung involvement, diffuse distribution, and AIP/ARDS pattern were associated with high-grade pneumonitis and RP-related death. AIP/ARDS pattern was a significant factor for high-grade pneumonitis (OR:12.62, p = 0.01) in multivariable analyses adjusting for clinical variables.

CONCLUSION

COP pattern was the most common radiographic pattern for symptomatic RP in lung cancer patients. AIP/ARDS pattern was significantly associated with high-grade RP and RP-related deaths, and was an independent marker for high-grade RP. The recognition of the radiographic patterns of RP can help to effectively contribute to patient management.

Immune-Related Pneumonitis After Chemoradiotherapy and Subsequent Immune Checkpoint Blockade in Unresectable Stage III Non-Small-Cell Lung Cancer

Approximately one third of patients with non-small-cell lung cancer (NSCLC) present with stage III or locally advanced NSCLC. These patients have historically been managed with chemoradiotherapy. However, outcomes for these patients remain poor, with a 5-year survival rate between 15% and 32%. Immune checkpoint inhibitors have revolutionized the treatment of patients with NSCLC. One such agent, durvalumab, a selective high-affinity human immunoglobulin G1 monoclonal antibody that blocks programmed cell death ligand 1 binding to programmed cell death protein 1 and cluster of differentiation 80, was recently approved in the consolidation setting after completion of definitive platinum-based chemoradiotherapy and has become the current standard of care for patients with stage III locally advanced NSCLC. Immune checkpoint blockade is associated with increased risk of immunotherapy-related adverse events, which can be managed most effectively when detected early, ideally in the context of a multidisciplinary approach. Pneumonitis represents the potentially most severe and life-threatening of all reported immunotherapy-related adverse events, but it is further complicated in the context of recent prior therapies also known to cause pulmonary toxicity, such as radiotherapy. However, there are major gaps in our ability to identify immunotherapy-related pneumonitis and distinguish it from radiation pneumonitis. This review aims to define the key steps in the detection, diagnosis, and treatment of immunotherapy-related pneumonitis.

Imaging-based Biomarkers for Predicting and Evaluating Cancer Immunotherapy Response

Proper patient selection for immunotherapy is critical, as certain tumor microenvironments are more permissible to therapy than others. Currently, the use of programmed cell death ligand-1 (PD-L1) and microsatellite instability high and/or mismatch repair deficiency are used as biomarkers for immunotherapy response. To improve tumor characterization, methodologies are being developed to combine imaging with tumor immune environment characterization. Imaging of tumors from immunotherapy responders and nonresponders with various imaging modalities has led to the development of criteria that could predict patient response to immunotherapy. Additionally, radiomics-based artificial intelligence methods are being used to characterize tumor microenvironments to predict and evaluate immunotherapy responses, as well as to predict risk of immune-related adverse events. Molecular imaging techniques are also being developed for various modalities to observe tumor expression of immunotherapy targets, such as PD-L1 and, to confirm the target is being expressed on resident tumors. In all, the advancements of imaging techniques to define tumor immunologic characteristics will help to stratify patients who are more likely to respond to immunotherapies. Keywords: Computer Aided Diagnosis (CAD), Computer Applications-Virtual Imaging, Efficacy Studies, MR-Imaging, Molecular Imaging-Cancer, Molecular Imaging-Immunotherapy, Molecular Imaging-Nanoparticles, Molecular Imaging-Probe Development, Molecular Imaging-Target Development, SPECT/CT © RSNA, 2019.

Landscape of Immune-Related Pneumonitis in Cancer Patients with Asthma Being Treated with Immune Checkpoint Blockade

INTRODUCTION

Predicting the factors that increase the risk of immune-related pneumonitis, a potentially life-threatening complication of treatment with immune checkpoint inhibitors for cancer, is a clinical challenge. Baseline clinical factors such as asthma may portend the development of pneumonitis due to pre-existing airway inflammation prior to immunotherapy.

OBJECTIVE

The purpose of the study was to investigate whether a prior diagnosis of asthma is associated with an increased risk of immune-related pneumonitis in patients undergoing cancer immunotherapy.

METHODS

Patients at the Moores Cancer Center at UC San Diego Health undergoing immunotherapy were identified on an IRB-approved protocol. Clinical charts were reviewed for asthma documented in the medical records and CT scans were reviewed during and after treatment. Pneumonitis was defined as the onset of new pulmonary symptoms with characteristic imaging findings during or after a patient's first course of immunotherapy that could not be readily explained as infection or a progression of malignancy. It was graded according to the Common Terminology Criteria for Adverse Events.

RESULTS

A total of 187 patients were included. A diagnosis of asthma was found in the records of 26 cases (13.9%). Pneumonitis was found in 10 cases (5.35%); 50% were grade 2 and 50% were grade 3-4. Two of the grade 3-4 cases (40%) occurred in patients with non-small-cell lung cancer. Three patients with asthma developed pneumonitis (11.5% of patients with asthma), all grade 3-4. Only 28.6% of the non-asthma-pneumonitis cases were grade 3-4. All (100%) of the asthma-pneumonitis patients were former smokers, while 71.4% of the non-asthma-pneumonitis patients were former smokers.

CONCLUSION

A history of asthma may be associated with a higher grade of pneumonitis if it develops, and a history of smoking may augment this relationship.

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.

Managing Pulmonary Toxicities Associated with Immunotherapy: A Case Discussion

Immunotherapy has changed the field of oncology around the world with the approval of immune checkpoint inhibitors for a number of tumor types over the last 5 years. However, immune-mediated adverse events can be challenging and difficult to treat, with one of the most dire consequences being immune-mediated pneumonitis. KEY POINTS: Rapid intervention and aggressive management for grade 3 or greater pneumonitisSlow taper of steroids and also recommend pneumocystis carinii pneumonia prophylaxisMonitor carefully for a pneumonitis flare with steroid taper, which can occur in the absence of resuming anti-programmed cell death protein 1 (PD-1) [1], and do not resume anti-PD-1 therapy until completely off steroids and no clinical or radiologic evidence of recurrenceConsider observation without anti-PD-1 resumption-in this case, durable response was maintained even without resuming anti-PD-1 therapy.

Imaging of Cancer Immunotherapy: Current Approaches and Future Directions

Cancer immunotherapy using immune-checkpoint inhibitors has emerged as an effective treatment option for a variety of advanced cancers in the past decade. Because of the distinct mechanisms of immunotherapy that activate the host immunity to treat cancers, unconventional immune-related phenomena are encountered in terms of tumor response and progression, as well as drug toxicity. Imaging plays an important role in objectively characterizing immune-related tumor responses and progression and in detecting and monitoring immune-related adverse events. Moreover, emerging data suggest a promise for molecular imaging that can visualize the specific target molecules involved in immune-checkpoint pathways. In this article, the background and current status of cancer immunotherapy are summarized, and the current methods for imaging evaluations of immune-related responses and toxicities are reviewed along with their limitations and pitfalls. Emerging approaches with molecular imaging are also discussed as a future direction to address unmet needs.

Immunotherapy in oncology: a new challenge for radiologists

OBJECTIVE

In patients with oncologic disease, immunotherapy has become established as an alternative or complementary therapy to traditional treatment options (surgery, radiotherapy, and chemotherapy). Currently available immunotherapy modes can be divided into two types: passive and active. The active type strengthens the immune system's response to tumor cells by activating both humoral immunity and cell-mediated immunity, using the adaptive response. This article aims to analyze the radiologic patterns of the response to immunotherapy through immune-response-related criteria and to describe the main adverse effects associated with this treatment approach.

CONCLUSION

Imaging tests play a fundamental role in the follow-up of oncologic patients and in the assessment of their response to treatment. Immunotherapy represents a challenge for radiologists both in the evaluation of the response to immunotherapy and in the detection of the adverse effects associated with this treatment approach.

Hallmarks of Cancer in the Reading Room: A Guide for Radiologists

OBJECTIVE

The hallmarks of cancer are mechanisms that cells develop to undergo malignant transformation. The targeting of these hallmarks by newer cancer therapies results in new mechanisms of response, toxicity, and resistance. The purpose of this article is to review these hallmarks, their associated targeted therapies, imaging features of responses, and toxicities.

CONCLUSION

Ten hallmarks, among them proliferative signaling, angiogenesis, immune response, and genome instability, are reviewed. Molecular targeted therapies, including antiangiogenic factors and immune checkpoint inhibitors, target these hallmarks.

Pneumonitis in advanced non-small-cell lung cancer patients treated with EGFR tyrosine kinase inhibitor: Meta-analysis of 153 cohorts with 15,713 patients: Meta-analysis of incidence and risk factors of EGFR-TKI pneumonitis in NSCLC

PURPOSE

Pneumonitis is a significant toxicity of EGFR tyrosine kinase inhibitors (EGFR-TKI) in non-small-cell lung cancer (NSCLC) patients. We studied the incidence of pneumonitis in clinical trials of EGFR-TKI published in 2003-2017, and performed subgroups analyses to identity predisposing factors.

METHODS

Ovid-MEDLINE and EMBASE search up to 4/17/17 using the keywords, "erlotinib", "gefitinib", "afatinib", "osimertinib", and "lung cancer", resulted in a total of 153 eligible trial cohorts with 15,713 advanced NSCLC patients treated with EGFR-TKI. The pooled incidence of all-grade, high-grade, and grade 5 pneumonitis was obtained. Subgroup analyses were performed with meta-regression using study-level covariates.

RESULTS

Among the patients without prior exposure to EGFR-TKI, the overall incidence was 1.12% (95% CI:0.79-1.58%) for all-grade, 0.61% (95% CI:0.40-0.93%) for high-grade, and 0.20% (95% CI:0.11-0.38%) for grade 5 pneumonitis. The incidence was significantly higher in Japanese studies compared to studies of non-Japan origin, for all-grade (4.77% vs. 0.55%, p < 0.001), high grade (2.49% vs. 0.37%, p < 0.001), and grade 5 pneumonitis (1.00% vs. 0.18%, p < 0.001). Multivariate analyses demonstrated higher odds of pneumonitis in Japanese studies for all-grade (odds ratio [OR]: 5.04; 95% CI:3.14-8.11, p < 0.001), high-grade (OR: 4.45; 95% CI:2.50-7.93, p < 0.001), and grade 5 pneumonitis (OR: 4.55; 95% CI:2.20-9.44, p < 0.001) compared to others, after adjusting for types of EGFR-TKI and lines of therapy. In patients with EGFR retreatment analyzed separately, the pooled incidence was 1.13% (95% CI:0.40-3.15%) for all-grade, 0.49% (95% CI:0.21-1.11%) for high-grade, and 0.16% (95% CI:0.04-0.65%) for grade 5 pneumonitis.

CONCLUSIONS

The overall incidence of EGFR-TKI pneumonitis was 1.12% in patients without prior exposure to EGFR-TKI, and 1.13% in EGFR-TKI retreatment group. The cohorts from Japan had significantly higher incidence of pneumonitis, providing insights for further mechanistic studies.