Drug-induced sarcoidosis-like reaction in adjuvant immunotherapy: Increased rate and mimicker of metastasis

Organ-specific accuracy of [18F]FDG-PET/CT in identifying immune-related adverse events in patients with high-risk melanoma treated with adjuvant immune checkpoint inhibitor

PURPOSE

This study aimed to determine the organ-specific accuracy of [18F]FDG-PET/CT in identifying immune-related adverse events (irAEs) in patients with high-risk (stage III/IV) surgically resected melanoma treated with an adjuvant immune checkpoint inhibitor (ICI) and determine the incidence of irAEs within the first year after starting treatment.

MATERIALS AND METHODS

This registry-based study included individuals who had undergone surgical removal of melanoma and were undergoing adjuvant ICI treatment (either nivolumab or pembrolizumab). The study specifically enrolled patients who had undergone both a baseline and at least one subsequent follow-up [18F]FDG-PET/CT scan. Follow-up scans were performed every third month in the first year after surgery to screen for disease recurrence. We retrospectively compared the follow-up scans with baseline scans to identify irAEs. Clinical information on irAEs was obtained from medical records and served as a reference standard for determining the accuracy of [18F]FDG-PET/CT.

RESULTS

A total of 123 patients with 363 [18F]FDG-PET/CT scans were included, and 65 patients (52.8%) developed irAEs. In decreasing order, the organ-specific incidences of irAEs were: skin 26/65 (40%), muscle and joints 21/65 (32.3%), intestines 13/65 (20%), thyroid gland 12/65 (18.5%), lungs 4/65 (6.2%), and heart 2/65 (3.1%). The sensitivities and specificities of [18F]FDG-PET/CT for diagnosing irAEs were: skin 19% (95% CI: 7-39%) and 95% (88-98%), muscles and joints 71% (48-89%) and 83% (75-90%), intestines 100% (75-100%) and 85% (77-91%); thyroid gland 92% (62-99%) and 95% (89-98%), lungs 75% (19-99%) and 90% (83-95%), and heart 50% (13-99%) and 97% (92-99%), respectively.

CONCLUSION

[18F]FDG-PET/CT generally had moderate to high sensitivities (except for skin and heart) and specificities in diagnosing irAEs in patients receiving adjuvant ICI; this could be suggested to be systematically assessed and reported in scan reports.

[Drug-related exanthema under immunotherapy and targeted oncological therapy]

BACKGROUND

Oncological therapies can cause a variety of mucocutaneous adverse events. Exanthematous adverse events can be challenging in the context of the urgent need for cancer treatment due to their spread, sometimes rapid progression, and mucous membrane or organ involvement.

MATERIALS AND METHODS

This article provides an overview of the most important exanthematic dermatoses as side effects of modern drug-based tumor therapies with diagnostic and therapeutic information for clinicians, taking into account the current literature and guidelines.

RESULTS

Exanthematous adverse events of immune checkpoint inhibitors, EGFR antagonists, kinase inhibitors, bispecific T‑cell engagers, and the CCR4 inhibitor mogamulizumab are reviewed in detail.

CONCLUSIONS

Cutaneous side effects are common across all drug classes and cover a broad spectrum. While some adverse events are specific to one drug class, many exanthemas can occur with both oncological immunotherapies and various targeted therapies. A reliable diagnosis, dose adjustment or discontinuation of the offending agent in consultation with the treating oncologists and appropriate symptomatic therapy are important for correct management. In the case of severe, life-threatening drug reactions, however, permanent discontinuation of the drug is essential.

Sarcoidosis-like reactions in metastatic renal cell carcinoma patients treated with immune-based combinations

Aim: The incidence of drug-induced sarcoidosis-like reactions (DISR) in patients treated with immune checkpoint inhibitors (ICIs) is rising. We determine the incidence and characteristics of DISR in a metastatic renal cell carcinoma (mRCC) population. Methods: We retrospectively reviewed clinico-radiological data of 83 mRCC patients treated at a single institution with immune-based combinations. Results: 15 patients received immune-doublet (ipilimumab-nivolumab), while 68 patients received other immune-based combinations. Two cases of DISR (2.4%) were evidenced, with enlargement of mediastinal lymph nodes that mimicked disease progression, thus requiring a biopsy which showed histological features of DISR. Conclusion: In our series of the incidence of DISR, radiological and clinical features, are in line with literature. DISR diagnosis is often only radiological, and its occurrence is possibly associated with a better outcome.

Sarcoid-like Reactions to Immune Checkpoint Inhibitors

Immune checkpoint inhibitors (ICIs) can cause immune-mediated cutaneous adverse events, including sarcoid-like reactions. The aim of this study was to retrospectively analyze clinical and histologic data from patients who developed cutaneous sarcoid-like reactions between 2019 and 2022 while under treatment with ICIs. We studied 7 patients (6 women and 1 man) with a median age of 65years. Median time to onset of symptoms was 4months. The most common presentation was papular sarcoidosis of the knees followed by subcutaneous sarcoidosis. Diagnosis was confirmed histologically in all cases, and no differences were observed relative to idiopathic sarcoidosis. Discontinuation of ICI therapy was required in just two patients. ICI-induced sarcoid-like reactions tend to be mild and generally do not require treatment discontinuation. Histologic confirmation is essential for distinguishing these reactions from tumor progression.

[Translated article] Sarcoid-like Reactions to Immune Checkpoint Inhibitors

Immune checkpoint inhibitors (ICIs) can cause immune-mediated cutaneous adverse events, including sarcoid-like reactions. The aim of this study was to retrospectively analyze clinical and histologic data from patients who developed cutaneous sarcoid-like reactions between 2019 and 2022 while under treatment with ICIs. We studied 7 patients (6 women and 1 man) with a median age of 65years. Median time to onset of symptoms was 4months. The most common presentation was papular sarcoidosis of the knees followed by subcutaneous sarcoidosis. Diagnosis was confirmed histologically in all cases, and no differences were observed relative to idiopathic sarcoidosis. Discontinuation of ICI therapy was required in just two patients. ICI-induced sarcoid-like reactions tend to be mild and generally do not require treatment discontinuation. Histologic confirmation is essential for distinguishing these reactions from tumor progression.

Immunotherapy-induced exclusively cutaneous sarcoid-like reaction

Sarcoid-like reactions (SLRs) are rare, granulomatous inflammatory reactions to immune checkpoint inhibitors (ICIs) that can involve any organ but frequently affect the lungs, mediastinal lymph nodes and skin. We present a rare case of an exclusively cutaneous SLR due to pembrolizumab that clinically resembled dermatomyositis. A literature review yielded only 12 previously reported cases of ICI-induced cutaneous SLR without any systemic involvement. Our case highlights the diversity of presentations of cutaneous SLR and emphasises the importance of histological evaluation of new cutaneous eruptions.

Hilar/mediastinal and cutaneous drug-induced sarcoidosis-like reaction associated with immune checkpoint inhibitors in metastatic colorectal cancer: a case report

Background

Immune checkpoint inhibitors (ICIs) are the standard treatment for metastatic colorectal cancer (mCRC) with high microsatellite instability (MSI-H). Among immune-related adverse events (irAEs), drug-induced sarcoidosis-like reactions (DISR) are often difficult to differentiate from cancer progression.

Main Body

This is a case of a woman in her mid-60s, with mCRC (RAS wild/BRAF mutant/MSI-H) and abdominal lymph node metastasis, treated with four courses of ipilimumab + nivolumab every 3 weeks, followed by nivolumab every 2 weeks as third-line treatment. After treatment, the original lymph node metastases shrank, but hilar/mediastinal lymph nodes appeared. Endoscopic ultrasound-guided fine-needle aspiration of these lymph nodes revealed multiple epithelioid granulomas without necrosis, indicating a sarcoidosis-like reaction. Fluorodeoxyglucose-positron emission tomography scan showed abnormal subcutaneous accumulation in bilateral forearms and bilateral knee joints. Biopsy of the cutaneous lesions was also performed, which revealed epithelioid granulomas. As the patient had no symptoms in other organs, no specific therapeutic intervention was administered. After the discontinuation of immunotherapy, the sarcoidosis-like reaction regressed without cancer relapse.

Conclusions

Clinicians should be aware of the possibility of DISR as an irAE during the ICI treatment of mCRC. In suspected cases of DISR following ICI therapy, it is important to differentiate between cancer progression and DISR through histological diagnosis for the subsequent strategy, as radiological and serological findings are not definitive.

Differential diagnosis of pulmonary sarcoidosis: a review

Diagnosing pulmonary sarcoidosis raises challenges due to both the absence of a specific diagnostic criterion and the varied presentations capable of mimicking many other conditions. The aim of this review is to help non-sarcoidosis experts establish optimal differential-diagnosis strategies tailored to each situation. Alternative granulomatous diseases that must be ruled out include infections (notably tuberculosis, nontuberculous mycobacterial infections, and histoplasmosis), chronic beryllium disease, hypersensitivity pneumonitis, granulomatous talcosis, drug-induced granulomatosis (notably due to TNF-a antagonists, immune checkpoint inhibitors, targeted therapies, and interferons), immune deficiencies, genetic disorders (Blau syndrome), Crohn's disease, granulomatosis with polyangiitis, eosinophilic granulomatosis with polyangiitis, and malignancy-associated granulomatosis. Ruling out lymphoproliferative disorders may also be very challenging before obtaining typical biopsy specimen. The first step is an assessment of epidemiological factors, notably the incidence of sarcoidosis and of alternative diagnoses; exposure to risk factors (e.g., infectious, occupational, and environmental agents); and exposure to drugs taken for therapeutic or recreational purposes. The clinical history, physical examination and, above all, chest computed tomography indicate which differential diagnoses are most likely, thereby guiding the choice of subsequent investigations (e.g., microbiological investigations, lymphocyte proliferation tests with metals, autoantibody assays, and genetic tests). The goal is to rule out all diagnoses other than sarcoidosis that are consistent with the clinical situation. Chest computed tomography findings, from common to rare and from typical to atypical, are described for sarcoidosis and the alternatives. The pathology of granulomas and associated lesions is discussed and diagnostically helpful stains specified. In some patients, the definite diagnosis may require the continuous gathering of information during follow-up. Diseases that often closely mimic sarcoidosis include chronic beryllium disease and drug-induced granulomatosis. Tuberculosis rarely resembles sarcoidosis but is a leading differential diagnosis in regions of high tuberculosis endemicity.

Granulomatous and Sarcoid-like Immune-Related Adverse Events following CTLA4 and PD1 Blockade Adjuvant Therapy of Melanoma: A Combined Analysis of ECOG-ACRIN E1609 and SWOG S1404 Phase III Trials and a Literature Review

BACKGROUND

Treatment with immune checkpoint inhibitors (ICIs) has been linked to granulomatous and sarcoid-like lesions (GSLs) affecting different organs. This study sought to evaluate GSL incidence in patients with high-risk melanoma treated with cytotoxic T-lymphocyte antigen 4 (CTLA4) or programmed cell death 1 (PD1) blockade adjuvant therapy in two clinical trials: ECOG-ACRIN E1609 and SWOG S1404. Descriptions and GSL severity ratings were recorded.

METHODS

Data were collected from ECOG-ACRIN E1609 and SWOG S1404. Descriptive statistics along with GSL severity grades were reported. Additionally, a literature review for such cases was summarized.

RESULTS

A total of 11 GSL cases were reported among 2878 patients treated with either ICI or with High-Dose Interferon Alfa-2b (HDI) in ECOG-ACRIN E1609 and SWOG S1404 trials. Cases were numerically more commonly reported with ipi10, followed by pembrolizumab, ipi3, and HDI, respectively. Most of the cases were grade III. Further, organs involved included lung, mediastinal lymph nodes, skin and subcutaneous tissue, and eye. Furthermore, a summary of 62 reports in the literature was described.

CONCLUSIONS

GSLs following anti-CTLA4 and anti-PD1 antibody therapy in patients with melanoma were reported unusually. Reported cases ranged in grade from I to III and appeared manageable. Careful attention to these events and their reporting will be essential to better guide practice and management guidelines.

Retrospective study of the incidence of sarcoidosis-like reaction in patients treated with immunotherapy

AIM

To assess the frequency of radiographically evident drug-induced sarcoidosis-like reaction (DISR) in patients treated with anti-cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) therapy, anti-programmed cell death protein 1 (PD-1) therapy, or a combination of both in a single centre.

MATERIALS AND METHODS

The images and medical records of 457 patients with metastatic melanoma or head and neck cancer treated with either anti-CTLA-4 therapy, anti-PD-1 therapy, or a combination of both at University of California medical centre were reviewed retrospectively and the incidence of radiological manifestations of DISR was assessed among these treatment groups.

RESULTS

Radiological manifestations of DISR were found in 19/457 patients (4.1%). The mean interval from the initiation of immunotherapy to development of DISR was 5.5 months (range 2.3-13.5 months). Mean interval from radiological detection of DISR to imaging evidence of resolution was 5.8 months (range 1.6-18.3 months). Three patients out of 81 (3.7%), 11/297 (3.7%), and 5/79 (6.3%) developed sarcoidosis-like reaction after treatment with anti-CTLA-4 antibody, anti-PD-1 antibody, and a combination of both, respectively. Most patients with DISR were asymptomatic and did not require systemic therapy. Most patients did not demonstrate concomitant increased maximum standardised uptake value (SUVmax) in other organs on their integrated 2-[¹⁸F]-fluoro-2-deoxy-d-glucose (FDG) positron-emission tomography (PET)/computed tomography (CT).

CONCLUSIONS

In the present retrospective study of patients treated with immune checkpoint inhibitors (ICIs), DISR occurred in approximately 3.7% of patients treated with either anti-CTLA-4 or anti-PD-1 antibody and 6.3% of patients treated with a combination of both.

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.

Sarcoid-like reaction in patients with malignant tumors: Long-term clinical course and outcomes

Background

The development of non-caseating epithelioid cell granulomas in cancer patients who do not fulfill the systemic sarcoidosis criteria is termed sarcoid-like reaction (SLR). Little is known about this condition's natural course and impact on the prognosis of malignancy. We aimed to investigate the natural course and prognostic value of cancer-associated SLR.

Methods

Clinical data were retrospectively analyzed in 32 patients with biopsy-proven cancer-associated SLR. Among patients with non-small cell lung cancer (NSCLC), SLR cases (n = 8) were matched with non-SLR cases (n = 78) for survival analysis.

Results

Among the included patients, the mean age was 59.7 years, and 68.8% were female. The median follow-up period was 35.6 months [interquartile range (IQR): 14.0–61.4 months]. Of all the included malignancies (n = 32), breast cancer (25.0%) and NSCLC (25.0%) were the most common, with stage I being the most frequent tumor stage (59.4%). During follow-up, SLR progression to overt sarcoidosis was not observed. In the 28 patients with available follow-up computed tomography images (median interval: 24.9 months; IQR: 14.4–41.7), 4 patients received corticosteroids (n = 4), resulting to a decrease of SLR lesions. Meanwhile, among those who did not receive treatment (n = 24), the extent of SLR decreased or did not change in 85.7% of them, whereas 3.6% had increased SLR extent. Furthermore, among patients with NSCLC, SLR was not associated with overall survival [hazard ratio (HR) = 1.28, 95% confidence interval (CI): 0.02–67.71, P = 0.882] and recurrence of malignancy (HR = 1.27, 95% CI 0.21–7.51, P = 0.793) in the Cox proportional hazard regression model.

Conclusions

During the follow-up of cancer-related SLR, we found no further evidence for systemic sarcoidosis, and most of the lesions decreased or did not change. Development of SLR was also not associated with overall survival or disease-free survival in patients with NSCLC.

Nivolumab-induced systemic lymphadenopathy occurring during treatment of malignant melanoma: a case report

Nivolumab is an anti-programmed cell death protein 1 monoclonal antibody that exhibits significant efficacy in treating melanoma and other malignancies. However, various nivolumab-induced immune-related adverse events (irAEs) have been reported, and differentiating irAEs from tumor progression is sometimes difficult. Here, we report a case of reactive lymphadenopathy occurring after treatment with nivolumab. A 56-year-old man with stage IIIC melanoma received adjuvant therapy with nivolumab after wide local excision. He developed systemic lymphadenopathy and autoimmune hemolytic anemia 1 month after receiving seven cycles of nivolumab. Pathological analysis of a cervical lymph node biopsy specimen revealed no metastatic lesion or any other malignancy, including lymphoma. Thus, the patient was diagnosed with nivolumab-induced reactive lymphadenopathy. Systemic corticosteroids were administered to reduce hemolysis, which led to the resolution of lymphadenopathy. When progressive lymphadenopathy is observed in a patient who received immune checkpoint inhibitor therapy, reactive lymphadenopathy should be carefully distinguished from progression to lymphoid metastasis, and biopsy should be performed if needed.

Kutane Nebenwirkungen unter Immun-Checkpoint-Inhibitor-Therapie

Moderne Immuntherapeutika wie Nivolumab, Pembrolizumab oder Ipilimumab, die sogenannte Immun-Checkpoints blockieren, haben die onkologische Therapie in den letzten Jahren revolutioniert. Mit dem neuen Wirkmechanismus der Blockade wichtiger Kontrollpunkte im Immunsystem zeigen sich jedoch auch eine Vielzahl an unterschiedlichen Nebenwirkungen. Diese treten nicht selten an der Haut auf. Zu den häufigsten dermalen Reaktionen unter Immuntherapie zählen die Vitiligo, Exantheme, blasenbildende Reaktionen oder der Lichen planus. Ausgeprägter Juckreiz kann Patienten stark beeinträchtigen. Der Verlauf bei auf die Haut beschränkten Nebenwirkungen ist häufig mild und gut zu behandeln oder selbstlimitierend. Hauterscheinungen können jedoch auch als Symptom systemischer Reaktionen auftreten. Eine frühe Diagnosestellung, die Einleitung einer adäquaten Therapie sowie eine interdisziplinäre Betreuung bei komplexen Erkrankungen sind entscheidend, um dauerhafte Einschränkungen für die Patienten zu verhindern und eine sichere Behandlung der zugrundeliegenden Tumorerkrankung gewährleisten zu können.

Suspected immune checkpoint inhibitor-induced pulmonary sarcoid reaction in metastatic renal cell carcinoma

We present the case of a 50-year-old male patient with metastatic clear cell renal cell carcinoma (mRCC) who developed a diffuse pulmonary opacification and lymphadenopathy during nivolumab maintenance therapy. This was diagnosed as presumed sarcoid granulomatous inflammatory reaction secondary to immunotherapy, which resolved with holding off therapy and the nivolumab was resumed.

The Meaning of Lymphadenopathies During Adjuvant Durvalumab After Chemoradiotherapy for Lung Cancer: Thinking Beyond Disease Progression

Immune-checkpoint inhibitors (ICIs) have become the mainstay of treatment for many malignancies. With this new strategy, relevant immune-related adverse events (irAEs) have been reported, some of which can be mistaken for disease progression. To better illustrate the current challenges in diagnosing and managing a patient under adjuvant ICI treatment, we present the case of a 67-year-old female patient with stage IIIB unresectable, epidermal growth factor receptor (EGFR)-mutated, non-small-cell lung cancer who was initially treated with chemoradiotherapy, followed by immunotherapy with durvalumab. During the course of immunotherapy, the patient presented with madarosis and erythematous and endured skin lesions, in addition to lymphadenopathies and pulmonary infiltrates. She was started on first-line palliative treatment with an EGFR tyrosine kinase inhibitor. After reviewing the case, a multidisciplinary team meeting suggested diagnostic procedures, including a transbronchial needle aspiration from mediastinal lymph nodes. The histologic examination showed chronic systemic inflammation and non-caseating granulomas of the sarcoid type. In this case, palliative treatment was suspended and systemic therapy with prednisolone was initiated. The patient became asymptomatic and the previously observed radiologic abnormalities resolved. This case highlights the importance of early recognition and appropriate treatment of irAEs, mainly because these conditions remain poorly understood and are probably underdiagnosed. Considering differential diagnosis is paramount to guide clinical management, despite curative or palliative treatment intent.

Sarcoid-like Granulomatosis Associated with Immune Checkpoint Inhibitors in Melanoma

We aimed to review the clinical and biological presentation of granulomatosis associated with immune-checkpoint inhibitors (ICI) in patients with melanoma and to explore its association with classical sarcoidosis as well as with cancer response to ICI. To this end, a retrospective study on 18 melanoma patients with histologically proven ICI-induced granulomatosis over a 12-year period in a single center, as well as on 67 similar cases reported in the literature, was conducted. Results indicate ICI-induced granulomatosis is an early side effect (median time to onset: 2 months). Its clinical presentation, with predominant (90%) thoracic involvement, histopathological appearance and supposed underlying biology (involving the mTOR pathway in immune cells, Th17 polarization and TReg dysfunction) are indistinguishable from those of sarcoidosis. Moreover, it appears to be associated with ICI benefit (>65% objective response rate). Evolution is generally favorable, and symptomatic steroid treatment and/or ICI discontinuation are rarely necessary. ICI-associated granulomatosis is critical to explore for several reasons. Practically, it is essential to differentiate it from cancer progression. Secondly, this “experimental” sarcoidosis brings new elements that may help to address sarcoidosis origin and pathophysiology. Its association with ICI efficacy must be confirmed on a larger scale but could have significant impacts on patient management and biomarker definition.

The diagnostic accuracy and clinical impact of FDG-PET/CT follow-up for patients on adjuvant immunotherapy for high-risk malignant melanoma

OBJECTIVE

The benefit of FDG-PET/CT in follow-up of patients treated with adjuvant immunotherapy after resection of high-risk malignant melanoma (MM) is debated. This study evaluated the diagnostic accuracy and clinical impact of FDG-PET/CT for diagnosing MM recurrence during the first year after surgery.

METHODS

We retrospectively included 124 patients with resected high-risk MM, who received adjuvant immunotherapy and follow-up FDG-PET/CT. Clinical information and AJCC-8 stage was obtained from patients' medical records. Recurrence was verified by biopsy/progression on a subsequent scan leading to change of treatment. Non-recurrence was assumed when no metastases were observed until the subsequent follow-up scan. Incidence of recurrence, sensitivity, specificity, positive and negative predictive values (PPV and NPV) were outcome measures.

RESULTS

Incidence rate of MM recurrence was 0.27 [95% CI 0.17-0.37] per person-year during the first-year. Recurrence was detected in 13 patients (10%) at 3-month FDG-PET/CT, in 10 patients (8.1%) at 6 months, 1 patient (0.8%) at 9 months, 3 patients (2.4%) at 12 months. The overall sensitivity, specificity, PPV, and NPV were 97% [86-99], 82% [78-86], 39% [29-50], and 99% [98-99], respectively. The PPV trended towards higher values as disease stage increased. At the 3-month scan, the majority of actions derived from positive findings were surgery or earlier expedition of the subsequent follow-up scan.

CONCLUSION

The high rate of recurrence in patients with high-risk MM treated with adjuvant immunotherapy emphasizes the need for follow-up. The potential harm by a moderately low specificity reflecting a high number of false-positive results must be weighed against the benefit of early detection of recurrence.

"Skin rashes" and immunotherapy in melanoma: distinct dermatologic adverse events and implications for therapeutic management

Immune checkpoint inhibitors have shown efficacy in the treatment of different cancers by stimulating the antitumoral activity of the patient's immune system, representing a major breakthrough in the field of cancer therapy. Monoclonal antibodies including anti-cytotoxic T-lymphocyte-associated protein 4, anti-programmed cell death protein 1 and its ligand inhibitors have been approved for advanced melanoma among other solid cancers. Although immunotherapy demonstrated a good safety profile, a new spectrum of multisystemic immune-related adverse events has been recently reported due to their use. Cutaneous reactions represent one of the leading adverse events, often reported in literature as "skin rash", and rarely further characterized in distinct dermatologic entities. Herein we describe the distinctive cutaneous rashes occurring during immunotherapies for advanced melanoma, discussing implications in the treatment management.

Immune-checkpoint inhibitors: long-term implications of toxicity

The development of immune-checkpoint inhibitors (ICIs) has heralded a new era in cancer treatment, enabling the possibility of long-term survival in patients with metastatic disease, and providing new therapeutic indications in earlier-stage settings. As such, characterizing the long-term implications of receiving ICIs has grown in importance. An abundance of evidence exists describing the acute clinical toxicities of these agents, although chronic effects have not been as well catalogued. Nonetheless, emerging evidence indicates that persistent toxicities might be more common than initially suggested. While generally low-grade, these chronic sequelae can affect the endocrine, rheumatological, pulmonary, neurological and other organ systems. Fatal toxicities also comprise a diverse set of clinical manifestations and can occur in 0.4-1.2% of patients. This risk is a particularly relevant consideration in light of the possibility of long-term survival. Finally, the effects of immune-checkpoint blockade on a diverse range of immune processes, including atherosclerosis, heart failure, neuroinflammation, obesity and hypertension, have not been characterized but remain an important area of research with potential relevance to cancer survivors. In this Review, we describe the current evidence for chronic immune toxicities and the long-term implications of these effects for patients receiving ICIs.

Case Report: Sarcoid-Like Reactions and Tertiary Lymphoid Structures Following Dual Checkpoint Inhibition in a Patient with Early-Stage Lung Adenocarcinoma

Immune checkpoint inhibitor-induced sarcoid-like reactions and tertiary lymphoid structures (TLSs) are increasingly recognized but rarely reported in the same patient. We report a patient with lung adenocarcinoma who displayed sarcoid-like reactions in intrathoracic lymph nodes and tertiary lymphoid structures in surgical tumor after neoadjuvant therapy with nivolumab plus ipilimumab. Pathological examination revealed 50% residual tumor cells after treatment, and the CT evaluation of the primary tumor showed a stable disease. The patient experienced a recurrence eight months after surgery. To identify immune correlates of the limited response to immunotherapy, we conducted genomic and transcriptional assays, multiplex immunoassay, and multiplex immunohistochemistry on the pre- and post-immunotherapy tumor, lymph node, and plasma samples. TP53 R181C, KRAS G12C and SMAD4 R361H were identified as driver mutations of the tumor. In addition to abundant infiltrated lymphocytes, immunotherapy induced high levels of inhibitory components in post-treatment tissue samples, especially the FOXP3⁺ regulatory T cells in tumor and PD-L1 expression in the lymph node. Despite abundant TLSs in the post-treatment tumor, most TLSs were immature. Moreover, increasing levels of circulating checkpoint proteins BTLA, TIM-3, LAG-3, PD-1, PD-L1, and CTLA4 were observed during immunotherapy. Collectively, our observations revealed that high levels of immunosuppressive molecules in tumor, lymph nodes and/or in peripheral blood might indicate poor outcomes after immunotherapy, even in the setting of a patient with concurrent sarcoid-like reactions and tertiary lymphoid structures.

A case of sarcoidosis-like reaction associated with immune checkpoint inhibitors in metastatic renal cell carcinoma

INTRODUCTION

Immune checkpoint inhibitors are one of the standard treatments for metastatic renal cell carcinoma. Among immune-related adverse events, the sarcoidosis-like reaction is frequently difficult to differentiate from cancer progression.

CASE PRESENTATION

A 58-year-old man with renal cell carcinoma with multiple lung metastases was treated with ipilimumab and nivolumab after nephrectomy. Computed tomography after three courses of treatment revealed hilar/mediastinal lymphadenopathies, pleural nodules, and pulmonary interstitial lesions, whereas lung metastases were markedly regressed. Considering positive findings of Gallium scintigraphy and serological tests together, we clinically judged the new lesions as a sarcoidosis-like reaction and continued the treatment until cessation by liver dysfunction. After discontinuation of the immunotherapy, the sarcoidosis-like reaction was regressed without cancer relapse.

CONCLUSION

We report here the first case of a clinically diagnosed sarcoidosis-like reaction in metastatic renal cell carcinoma following treatment with immune checkpoint inhibitors.

Cutaneous sarcoidosis due to immune‐checkpoint inhibition and exacerbated by a novel BRAF dimerization inhibitor

Sarcoidosis is a non‐infective granulomatous disorder of unknown aetiology, with cutaneous involvement affecting up to 30% of patients. Drug‐induced sarcoidosis has been reported secondary to modern melanoma therapies including immune‐checkpoint inhibitors and first generation BRAF inhibitors such as vemurafenib and dabrafenib. Herein, we report a case of cutaneous micropapular sarcoidosis that first developed on immune‐checkpoint inhibition with ipilimumab and nivolumab for metastatic melanoma, which was exacerbated and further complicated by pityriasis rubra pilaris‐like palmar plaques upon transition to a next‐generation BRAF‐dimerisation inhibitor. Both the micropapular eruption and palmar plaques rapidly resolved after cessation of the novel BRAF‐inhibitor and concurrent commencement of hydroxychloroquine. It is unclear how inhibition of BRAF‐dimerisation results in granuloma formation, though upregulation of T_H1/T_H17 T‐cells and impairment of T‐reg cells may be responsible. Clinicians should be aware of the potential for exacerbation of sarcoidosis when transitioning from immune‐checkpoint inhibitors to these novel BRAF‐dimerisation inhibitors, particularly as their uptake in treating cancers increases beyond clinical trials. Further studies are required to assess whether these next‐generation agents can trigger sarcoidosis de‐novo, or simply exacerbate pre‐existing sarcoidosis.

Sarcoidosis-like reaction after neoadjuvant pembrolizumab combined with chemotherapy mimicking disease progression of NSCLC induced encouraging discovery of pathological complete response

Neoadjuvant chemoimmunotherapy has demonstrated improved efficacy and prognosis in stage IIa–IIIb patients with non‐small cell lung cancer (NSCLC). Drug‐induced sarcoidosis‐like reaction (DISR), an autoimmune reaction, has been reported as a type of immune‐related adverse event that may mimic disease progression. Here, we report the case of patient with NSCLC who developed DISR during neoadjuvant chemoimmunotherapy and finally achieved pathological complete response after surgery.

Review BRAF inhibition and the spectrum of granulomatous reactions

BRAF-inhibitors have emerged as a promising targeted therapy for malignancies with BRAF mutations, particularly metastatic melanoma. However, granulomatous reactions including sarcoidosis and sarcoid-like-reactions have been reported as a consequence of BRAF-inhibition. It is important to adequately characterise these granulomatous reactions including cutaneous manifestations and systemic involvement, in order to guide investigations and management. A literature review was conducted to characterise the spectrum of granulomatous reactions associated with BRAF-inhibitors - identifying 55 reactions affecting 51 patients, with 37 reactions limited to cutaneous involvement. Further, possible correlation with cancer response, mechanisms of granuloma formation, as well as a proposed workup and management approach for these granulomatous reactions are presented.

The diagnosis and management of sarcoid-like reactions in patients with melanoma treated with BRAF and MEK inhibitors. A case series and review of the literature

Sarcoidosis and sarcoid-like reactions (SLR) have been repeatedly reported in patients with melanoma treated with BRAF and MEK inhibitors. In the current study we present three patients that developed SLR under treatment with BRAF and mitogen-activated protein kinase (MEK) inhibitors for melanoma. Two patients developed mediastinal lymphadenitis with histological features of an SLR while on targeted therapy in the adjuvant setting, whereas one patient with metastatic melanoma developed granulomatous nephritis while receiving combination treatment with BRAF/MEK inhibitors and atezolizumab. In addition, we review the published literature on the pathogenesis, clinical characteristics, histologic features, imaging findings, and other potential useful diagnostic tools. We also address the need for a common terminology for these cases and propose an algorithm for the accurate diagnosis of BRAF/MEK inhibitor-induced SLR. We also review the currently available data on the treatment of these patients and suggest a treatment approach for SLR in patients with melanoma, as well as for the management of melanoma when SLR emerges.

Tumor-Associated Granulomas Preceding a Diagnosis of Thoracic Sarcoidosis: A Retrospective, Single-Center Cohort Study

There is a relationship between systemic sarcoidosis (SS) and malignancy. Sarcoidosis results from an exaggerated immune response in genetically susceptible individuals. In oncologic patients with sarcoidosis, tumoral antigens and antineoplastic treatment are considered potential triggering factors. The observation of a patient with granulomas in a parotid carcinoma who later developed SS led us to review the previous tumors of patients with SS. The aim of the study is to see whether granulomas were already present in the tumors that preceded sarcoidosis. We identified 196 sarcoidosis patients, 47 of whom had previously had a tumor. We were able to review 29 cases, 12 of which showed tumor-associated granulomas (TAGs) (41.4%). This ratio is much higher than that of the normal population (4.4–13.8). We analyzed five control patients without sarcoidosis for each tumor. In conclusion, we observed an increased number of TAGs in patients who later developed SS. This finding reinforces a pathogenic relationship between SS and neoplasia. The histology of tumors in patients with SS should be reviewed in an attempt to identify granulomas.

Assessment of early metabolic progression in melanoma patients under immunotherapy: an 18F-FDG PET/CT study

BACKGROUND

The usage of immune checkpoint inhibitors (ICIs) is the standard practice for the treatment of metastatic melanoma. However, a significant amount of patients show no response to immunotherapy, while issues on its reliable response interpretation exist. Aim of this study was to investigate the phenomenon of early disease progression in 2-deoxy-2-(18F)fluoro-D-glucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) in melanoma patients treated with ICIs.

METHODS

Thirty-one patients under ICIs serially monitored with 18F-FDG PET/CT were enrolled. All patients exhibited progressive metabolic disease (PMD) after two ICIs' cycles according to the European Organization for Research and Treatment of Cancer (EORTC) criteria, and were characterized as unconfirmed PMD (uPMD). They were further followed with at least one PET/CT for either confirmation of PMD (cPMD) or demonstration of pseudoprogression remission. Patients were also evaluated with the PET Response Evaluation Criteria for Immunotherapy (PERCIMT). Moreover, in an attempt to investigate immune activation, the spleen to liver ratios (SLRmean, SLRmax) of 18F-FDG uptake were measured.

RESULTS

Median follow up was 69.7 months [64.6-NA]. According to EORTC, 26/31 patients with uPMD eventually showed cPMD (83.9%) and 5/31 patients showed pseudoprogression (16.1%). Patients with cPMD (n = 26) had a median OS of 10.9 months [8.5-NA], while those with pseudoprogression (n = 5) did not reach a median OS [40.9-NA]. Respectively, after application of PERCIMT, 2/5 patients of the pseudoprogression group were correctly classified as non-PMD, reducing the uPMD cohort to 29 patients; eventually, 26/29 patients demonstrated cPMD (89.7%) and 3/29 pseudoprogression (10.3%). One further patient with pseudoprogression exhibited transient, sarcoid-like, mediastinal/hilar lymphadenopathy, a known immune-related adverse event (irAE). Finally, patients eventually showing cPMD exhibited a significantly higher SLRmean than those showing pseudoprogression after two ICIs' cycles (p = 0.038).

CONCLUSION

PET/CT, performed already after administration of two ICIs' cycles, can identify the majority of non-responders in melanoma immunotherapy. In order to tackle however, the non-negligible phenomenon of pseudoprogression, another follow-up PET/CT, the usage of novel response criteria and vigilance over emergence of radiological irAEs are recommended. Moreover, the investigation of spleen glucose metabolism may offer further prognostic information in melanoma patients under ICIs.

Melanoma and Sarcoidosis in Patients Receiving or Not Antineoplastic Therapy

Sarcoidosis and sarcoid-like reactions have been associated with many solid tumors including malignant melanoma. There are reports of melanoma patients who develop sarcoidosis without having received any antineoplastic treatment, but there are also melanoma patients who have received immunotherapy or targeted therapy and, therefore, develop drug-associated sarcoidosis. Herein, we describe 2 cases of thoracic sarcoidosis which occurred in asymptomatic patients with known malignant melanoma. The first patient had metastatic disease, and she was under melanoma treatment with BRAF/MEK inhibitors at the time of sarcoidosis diagnosis. The second case involves a patient with early stage melanoma who had received no antineoplastic treatment. In both cases, the thoracic lesions were suspicious for metastatic involvement, and it was the biopsy which gave the diagnosis of granulomatous disease. Sarcoidosis induced by immune checkpoint or BRAF/MEK inhibitors seems to be more frequent in real-world studies than in large phase 3 melanoma trials. Sarcoidosis can mimic metastasis, predominately in mediastinum, representing a diagnostic pitfall. Therefore, biopsies must always be performed to exclude the metastatic spread before initiation of any antineoplastic treatment.

Drug-induced sarcoidosis-like reactions

PURPOSE OF REVIEW

Sarcoidosis is a complex granulomatous disease of unknown cause. Several drug categories are able to induce a systemic granulomatous indistinguishable from sarcoidosis, known as drug-induced sarcoidosis-like reaction (DISR). This granulomatous inflammation can resolve if the medication is discontinued. In this review, we discuss recent literature on medication associated with DISR, possible pathophysiology, clinical features, and treatment.

RECENT FINDINGS

Recently, increasing reports on DISR have expanded the list of drugs associated with the systemic granulomatous eruption. Most reported drugs can be categorized as combination antiretroviral therapy, tumor necrosis factor-α antagonist, interferons, and immune checkpoint inhibitors, but reports on other drugs are also published. The proposed mechanism is enhancement of the aberrant immune response which results in systemic granuloma formation. It is currently not possible to know whether DISR represents a separate entity or is a triggered but 'true' sarcoidosis.As DISRs may cause minimal symptoms, treatment is not always necessary and the benefits of continuing the offending drug should be weighed against clinical symptoms and organ dysfunction. Treatment may involve immunosuppressive medication that is used for sarcoidosis treatment.

SUMMARY

In this article, we review recent insights in DISR: associated drug categories, clinical presentation, diagnosis, and treatment. Additionally, we discuss possible mechanisms of DISR which can add to our knowledge of sarcoidosis pathophysiology.

Granulomatous colitis in a patient with metastatic melanoma under immunotherapy: a case report and literature review

BACKGROUND

Immune checkpoint inhibitors (ICPIs) have changed the way advanced malignancies are currently confronted, improving cancer patients' outcomes but also generating distinct immune-related (ir) adverse events. ICPIs-induced colitis is a common complication showing different clinical and histological manifestations. In the literature review, 14 cases with ICPIs related colon granulomas have been reported in 5 studies with either limited or unavailable information regarding histology. Granulomatous reactions can be mistakenly perceived as disease recurrence or progression. Better understanding and identification of this infrequent histological display can help to avoid misdiagnosis and mismanagement.

CASE PRESENTATION

A 63-year-old female patient with metastatic melanoma was admitted to the hospital with symptoms of nausea, persistent diarrhea and shivering fever under consecutive treatments with ICPIs, initially pembrolizumab and subsequently ipilimumab. Sigmoidoscopy was performed revealing mucosal edema, hyperemia and erosions of the rectum and sigmoid colon. Histological evaluation of sigmoid colon mucosa biopsies revealed an unusual colitis pattern characterized by multiple intracryptal granulomas attributed to ICPIs therapy. Steroids were administered and the patient recovered. ICPIs treatment was discontinued. The patient was subsequently treated with chemotherapy but follow up radiology showed disease progression. A re-challenge with another ICPI regimen was decided and the patient is currently under immunotherapy with stable disease regarding melanoma status and without any sign of colitis recurrence.

CONCLUSIONS

The present report provides detailed histological description of a distinctive ICPIs-induced granulomatous colitis and highlights the need for awareness of the distinct adverse events and reaction patterns in the context of immunotherapy.

Epithelioid granulomatous lesions express abundant programmed death ligand-1 (PD-L1): a discussion of adverse events in anti-PD-1 antibody-based cancer immunotherapy

The immune system is often called a double-edged sword, due to the inextricable link between cancer immunity and allergy/autoimmunity. Intriguingly, a growing number of cases have been reported in which PD-1 blockade triggers the exacerbation of tuberculosis (TB), an organ-invasive granulomatous disease caused by bacterial infection. As a result, the exacerbation of TB is now considered a severe adverse effect of nivolumab and pembrolizumab. In this letter, we report the strong expression of PD-L1 in epithelioid granulomatous lesions in tuberculosis, sarcoidosis, Crohn's disease, and foreign body granuloma. In addition, we discussed the exacerbation of tuberculosis after anti-PD-1 antibody-based cancer immunotherapy.

Identification of characteristic subepithelial surface granulomatosis in immune-related adverse event-associated enterocolitis

Immune checkpoint inhibitors (ICIs) have provided an additional treatment option for various types of human cancers. However, ICIs often induce various immune-related adverse events (irAEs). Enterocolitis is a major irAE with poorly understood histopathological characteristics. In this study, we retrospectively investigated the histopathology of colon tissue samples from 17 patients treated with ICIs. There were two major histological patterns of colitis: an ulcerative colitis-like pattern and a graft vs host disease-like pattern. Although these two patterns of colitis were mutually exclusive, both patterns often showed a characteristic that we call "subepithelial surface granulomatosis" (SSG), which has not been reported in other types of colitis. SSG was found even in colon tissue without symptoms or endoscopic findings of colitis. Given the increasing reports of sarcoid reaction or exacerbation of tuberculosis after treatment with ICIs, granuloma formation could be a histological hallmark of systemic immune activation by ICIs. Although statistical significance was not obtained, probably because of the small sample size, SSG may be a surrogate biomarker of systemic anticancer immune activation. We propose that a prospective study with larger sample size be performed.

Sarcoidosis-like reactions in cancer patients treated with immune checkpoint inhibitors: experience in a Spanish hospital

BACKGROUND

Immune checkpoint inhibitors (ICI) have been associated with several immune-related adverse events, including sarcoidosis-like reactions (SLR). SLR, which has a low prevalence but an increasing incidence, is similar to sarcoidosis in terms of histology, and clinical and radiological manifestations. The most commonly affected organs are hilar and mediastinal lymph nodes and skin. SLR is an exclusion diagnosis, so a lymph node biopsy can be useful to distinguish between tumor progression and SLR, particularly in tumors in which nodal involvement is very common.

PATIENTS AND METHODS

We performed a retrospective analysis of SLR in all cancer patients receiving ICIs in our institution between January 2016 and June 2020.

RESULTS

Among the 1063 treated patients, seven experienced SLR, four of whom were symptomatic (cough, skin lesions, arthralgia), with time to onset ranging from 1.5 to 6.7 months after ICI initiation. All seven patients had bilateral hilar lymphadenopathy, and granulomatous reactions in five of the six patients with lymph node biopsies. SLR improved in all patients, including four patients who continued with ICI. Three patients received corticosteroids and/or stopped ICI therapy. Four of these patients had partial responses at the time SLR was identified.

CONCLUSION

Management of SLR lacks a consensus recommendation, although corticosteroids and/or stopping the ICI are generally implemented. The potential consequences of stopping anticancer treatment should be taken into consideration, particularly in the absence of clear management recommendations.

Challenges in sarcoidosis and sarcoid-like reactions associated to immune checkpoint inhibitors: A narrative review apropos of a case

Sarcoidosis and sarcoid-like reactions (SLRs) may develop in association with various malignancies, as well as in association to certain oncologic drugs, including immune checkpoint inhibitors (ICIs). We aimed to perform a narrative review with regard to the development of ICIs-associated sarcoidosis or SLRs, and to discuss the corresponding diagnostic and therapeutic challenges raised in this scenario. Apropos of a melanoma patient developing SLRs while treated with ipilimumab and nivolumab, we searched for clinically evident, ICIs-associated sarcoidosis or SLRs in the English literature. We recorded the oncologic characteristics, including type of malignancy and type of ICI, the phenotypic characteristics of sarcoidosis/SLRs, as well as the impact on immunotherapy. Including our patient, we identified 80 ICIs-associated sarcoidosis or SLRs cases. Both sexes were equally affected (40 F/40 M) and the most common malignancy was melanoma (65/80, 81.3%). Concerning the oncologic treatment, there was a predilection for pembrolizumab (23/80, 28.7%), followed by the ipilimumab/nivolumab combination (21/80, 26.3%), ipilimumab (18/80, 22.5%), nivolumab (16/80, 20.0%). Although in the majority of the cases (52/80, 65.0%) there was no need for systemic prednisolone for the management of sarcoidosis, a significant proportion of patients finally discontinued ICIs treatment (44/80, 55.0%). Phenotypically, sarcoidosis and SLRs highly imitate oncologic progression posing diagnostic difficulties. A therapeutic dilemma is also raised when there is a need for systemic prednisolone, since the latter may jeopardize the therapeutic efficacy of immunotherapy. Sarcoidosis and SLRs, though rare, can present in oncologic patients treated with ICIs. Clinicians should be aware of this possibility and the related diagnostic and therapeutic challenges they have to face in this scenario.

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.

Sarcoidosis and Cancer: A Complex Relationship

Sarcoidosis is a systemic disease of unknown etiology, characterized by the presence of non-caseating granulomas in various organs, mainly the lungs, and the lymphatic system. Since the individualization of sarcoidosis-lymphoma association by Brincker et al., the relationship between sarcoidosis or granulomatous syndromes and malignancies has been clarified through observational studies worldwide. Two recent meta-analyses showed an increased risk of neoplasia in sarcoidosis. The granulomatosis can also reveal malignancy, either solid or hematological, defining paraneoplastic sarcoidosis. Recent cancer immunotherapies, including immune checkpoint inhibitors (targeting PD-1, PD-L1, or CTLA-4) and BRAF or MEK inhibitors were also reported as possible inducers of sarcoidosis-like reactions. Sarcoidosis and neoplasia, especially lymphoma, can show overlapping presentations, thus making the diagnosis and treatment harder to deal with. There are currently no formal recommendations to guide the differential diagnosis workup between the evolution of lymphoma or a solid cancer and a granulomatous reaction associated with neoplasia. Thus, in atypical presentations (e.g., deeply impaired condition, compressive lymphadenopathy, atypical localization, unexplained worsening lymphadenopathy, or splenomegaly), and treatment-resistant disease, targeted biopsies on suspect localizations with histological examination could help the clinician to differentiate neoplasia from sarcoidosis. Pathological diagnosis could sometimes be challenging since very few tumor cells may be surrounded by massive granulomatous reaction. The sensitization of currently available diagnostic tools should improve the diagnostic accuracy, such as the use of more “cancer-specific” radioactive tracers coupled with Positron Emission Tomography scan.