Drug-induced sarcoidosis-like reactions

Sarcoidosis-Like Reaction After Chemotherapy Mimicking Metastasis in a Patient With Two Synchronous Tumors: A Case Report

Sarcoidosis presents a diagnostic challenge due to its diverse clinical manifestations and potential to mimic malignancies. We report a clinical case involving a 46-year-old woman diagnosed with localized synchronous ovarian and endometrial carcinomas treated with surgery. Following adjuvant chemotherapy and radiotherapy, the patient developed suspicious pulmonary micronodules and lymphadenopathy observed in imaging studies, raising concerns about cancer recurrence. Histopathological analysis revealed chronic granulomatous inflammation without evidence of malignancy, leading to a diagnosis of a sarcoidosis-like reaction secondary to chemotherapy. Remarkably, these lesions resolved spontaneously without specific intervention. This case emphasizes the importance of a multidisciplinary approach in managing complex oncological presentations and underscores the significance of histopathological examination in distinguishing between malignancy and chemotherapy-induced sarcoidosis-like reactions.

The immunopathogenesis of sarcoidosis

Sarcoidosis is a granulomatous multiorgan disease, thought to result from exposure to yet unidentified antigens in genetically susceptible individuals. The exaggerated inflammatory response that leads to granuloma formation is highly complex and involves the innate and adaptive immune system. Consecutive immunological studies using advanced technology have increased our understanding of aberrantly activated immune cells, mediators and pathways that influence the formation, maintenance and resolution of granulomas. Over the years, it has become increasingly clear that disease immunopathogenesis can only be understood if the clinical heterogeneity of sarcoidosis is taken into consideration, along with the distribution of immune cells in peripheral blood and involved organs. Most studies offer an immunological snapshot during disease course, while the cellular composition of both the circulation and tissue microenvironment may change over time. Despite these challenges, novel insights on the role of the immune system are continuously published, thus bringing the field forward. This review highlights current knowledge on the innate and adaptive immune responses involved in sarcoidosis pathogenesis, as well as the pathways involved in non-resolving disease and fibrosis development. Additionally, we describe proposed immunological mechanisms responsible for drug-induced sarcoid like reactions. Although many aspects of disease immunopathogenesis remain to be unraveled, the identification of crucial immune reactions in sarcoidosis may help identify new treatment targets. We therefore also discuss potential therapies and future strategies based on the latest immunological findings.

Increased proportions of circulating PD-1+ CD4+ memory T cells and PD-1+ regulatory T cells associate with good response to prednisone in pulmonary sarcoidosis

BACKGROUND

The treatment response to corticosteroids in patients with sarcoidosis is highly variable. CD4+ T cells are central in sarcoid pathogenesis and their phenotype in peripheral blood (PB) associates with disease course. We hypothesized that the phenotype of circulating T cells in patients with sarcoidosis may correlate with the response to prednisone treatment. Therefore, we aimed to correlate frequencies and phenotypes of circulating T cells at baseline with the pulmonary function response at 3 and 12 months during prednisone treatment in patients with pulmonary sarcoidosis.

METHODS

We used multi-color flow cytometry to quantify activation marker expression on PB T cell populations in 22 treatment-naïve patients and 21 healthy controls (HCs). Pulmonary function tests at baseline, 3 and 12 months were used to measure treatment effect.

RESULTS

Patients with sarcoidosis showed an absolute forced vital capacity (FVC) increase of 14.2% predicted (± 10.6, p < 0.0001) between baseline and 3 months. Good response to prednisone (defined as absolute FVC increase of ≥ 10% predicted) was observed in 12 patients. CD4+ memory T cells and regulatory T cells from patients with sarcoidosis displayed an aberrant phenotype at baseline, compared to HCs. Good responders at 3 months had significantly increased baseline proportions of PD-1+CD4+ memory T cells and PD-1+ regulatory T cells, compared to poor responders and HCs. Moreover, decreased fractions of CD25+ cells and increased fractions of PD-1+ cells within the CD4+ memory T cell population correlated with ≥ 10% FVC increase at 12 months. During treatment, the aberrantly activated phenotype of memory and regulatory T cells reversed.

CONCLUSIONS

Increased proportions of circulating PD-1+CD4+ memory T cells and PD-1+ regulatory T cells and decreased proportions of CD25+CD4+ memory T cells associate with good FVC response to prednisone in pulmonary sarcoidosis, representing promising new blood biomarkers for prednisone efficacy.

TRIAL REGISTRATION

NL44805.078.13.

Ocular Sarcoidosis

Sarcoidosis frequently affects the eye and can do so in many different ways. Sarcoidosis causing uveitis can have distinctive features that facilitate identifying sarcoidosis as the cause of the uveitis. Progress is being made in elucidating ocular sarcoidosis, as for example, by transcriptomics, genetics, therapy, and imaging.

Cardiothoracic complications of immune checkpoint inhibitors

A paradigm shift in cancer treatment occurred with the advent of immune checkpoint inhibitors (ICI). ICI therapy has improved tumor response and increased overall survival in patients with solid tumors and hematologic malignancies. While ICI therapy has improved overall patient outcomes in oncology, it has also introduced novel adverse effects called immune-related adverse effects (irAEs). Studies have shown that the development of irAEs is associated with improved overall survival, but certain irAEs like pneumonitis and myocarditis are life threatening, and could result in death if not identified and treated early. Therefore, it is important for radiologists to be aware of complications arising from ICI administration, especially those related to the heart and lungs as they are associated with greater mortality. This paper will review the imaging features of cardiothoracic toxicities, recurrent and chronic irAEs, and atypical tumor responses associated with irAEs.

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.

Tumor necrosis factor-α inhibitor-related immune disorders

Biotechnological monoclonal antibodies and receptor antagonists capable of targeting specific inflammatory actors, such as cytokines, cytokines receptors, co-stimulatory molecules or leukocyte populations, have emerged as an alternative to conventional therapies for treating systemic inflammatory diseases with immune pathogenesis. However, there is no doubt that, with a frequency that is not exceptionally high but also not negligible, immunotherapies can favour the development of systemic and organ-specific immune-mediated disorders. It has become increasingly evident that interference with a specific immune pathway may favour the activation of opposing compensatory signalling, which may exacerbate underlying subclinical disorders or cause immune-mediated diseases completely different from the underlying disease. The 'compensatory immunological switch' has emerged primarily in patients treated with tumor necrosis factor (TNF) -α inhibitors, the first biological drugs approved for treating systemic inflammatory diseases with immune pathogenesis. In this Review, we describe the clinical features and predisposing factors of the main TNF-α inhibitor-related immune disorders, organising them into subclinical serological autoimmunity, autoimmune disorders other than those for which TNF-α inhibitors are indicated, and paradoxical reactions. We also discuss the underlying pathogenetic mechanisms and precautions for use in the therapeutic management of these patients. Better understanding of the complex phenomenon of the 'compensatory immunological switch', which TNF-α inhibitors and other biological drugs might trigger, can help not only appropriately managing immune-mediated disorders, but also better interpreting the heterogeneity of the pathogenetic mechanisms underlying certain chronic inflammatory conditions that, although different from each other, are arbitrarily placed in the context of overly generic nosological entities.

Sarcoid-Like Reaction in the Kidney Following Rituximab for Mantle Lymphoma in a 60-Year-Old Man

The sarcoid-like reaction is a rare autoinflammatory disease that can affect lymph nodes or organs but does not meet the diagnostic criteria for systemic sarcoidosis. Several drug classes have been associated with the development of a systemic sarcoid-like reaction, which defines drug-induced sarcoidosis-like reactions and can affect a single organ. Anti-CD20 antibodies (rituximab) have rarely been reported as responsible for this reaction and this adverse effect has mainly been described during the treatment of Hodgkin's lymphoma. We report a unique case of a sarcoid-like reaction complicating rituximab following the treatment of a mantle cell lymphoma and interesting only the kidney. The 60-year-old patient presented with severe acute renal failure 6 months after the end of his r-CHOP protocol and the urgent renal biopsy revealed acute interstitial nephritis rich in granulomas without caseous necrosis. After ruling out other causes of granulomatous nephritis, a sarcoid-like reaction was retained since infiltration was limited to the kidney. The temporal relationship between rituximab administration and the sarcoid-like reaction onset in our patient supported the diagnosis of a rituximab-induced sarcoidosis-like reaction. Oral corticosteroid treatment led to rapid and lasting improvement in renal function. Clinicians should be warned of this adverse effect and regular and prolonged monitoring of renal function should be recommended during the follow-up of patients after the end of treatment with rituximab.

Renal sarcoidosis

Sarcoidosis is a systemic inflammatory disease of unknown etiology. The pathogenesis rests on an aberrant T cell response to unidentified antigens in individuals predisposed by genetic and environmental factors. Increased expression of polarized macrophages and disequilibrium between effector and regulator T cells contribute to the formation of noncaseating granulomas, that are frequently found in affected organs. The main kidney abnormalities in sarcoidosis are granulomatous interstitial nephritis (GIN) and hypercalcemia-related disorders. The clinical diagnosis is difficult. The outcome is variable, ranging from spontaneous remission to end-stage kidney disease (ESKD). Early diagnosis and prompt treatment with corticosteroids can improve the prognosis. Hypercalcemia may be responsible for acute kidney injury (AKI) caused by vasoconstriction of afferent arterioles. Complications of persistent hypercalcemia include nephrocalcinosis and renal stones. In patients with ESKD, dialysis and transplantation can offer results comparable to those observed in patients with other causes of kidney failure. Based on a review of the literature, we present an overview of the etiopathogenesis, the renal manifestations of sarcoidosis and their complications, management and prognosis.

Sarcoidosis, granulomas and myopathy syndromes: A clinical-pathology review

Muscle involvement in sarcoidosis is common by pathologic analysis, but symptomatic disorders are less frequent. Sarcoidosis-related muscle pathology includes non-caseating granulomas, muscle fiber changes that are diffuse or anatomically related to granulomas, and perimysial connective tissue with histiocyte-associated damage. The mechanisms by which granulomas form, enlarge and damage muscle tissues are incompletely understood. Sarcoidosis-related clinical syndromes with muscle involvement include: chronic myopathies with proximal weakness; nodular disorders; subacute onset disorders involving proximal or eye muscles; myalgia or fatigue syndromes; and, possibly, inclusion body myositis-like disorders. Corticosteroid treatment may benefit some syndromes, but clinical trials are necessary.

Comorbidities of sarcoidosis

Sarcoidosis is a heterogeneous disease, which can affect virtually every body organ, even though lungs and intra thoracic lymph nodes are almost universally affected. The presence of noncaseating granulomas is the histopathological hallmark of the disease, and clinical picture depends on the organs affected. Data about interaction between sarcoidosis and comorbidities, such as cardiovascular and pulmonary diseases, autoimmune disorders, malignancy and drug-related adverse events are limited. Several lung conditions can be associated with sarcoidosis, such as pulmonary hypertension and fibrosis, making it difficult sometimes the differentiation between complications and distinctive pathologies. Their coexistence may complicate the diagnosis of sarcoidosis and contribute to the highly variable and unpredictable natural history, particularly if several diseases are recognised. A thorough assessment of specific disorders that can be associated with sarcoidosis should always be carried out, and future studies will need to evaluate sarcoidosis not only as a single disorder, but also in the light of possible concomitant conditions.Key messagesComorbidities in sarcoidosis are common, especially cardiovascular and pulmonary diseases.In the diagnostic workup, a distinction must be made between sarcoidosis-related complaints and complaints caused by other separate disorders. It can be very difficult to distinguish between complications of sarcoidosis and other concomitant conditions.The coexistence of multiple conditions may complicate the diagnosis of sarcoidosis, affect its natural course and response to treatment.

Drug-induced comorbidities in patients with sarcoidosis

PURPOSE OF REVIEW

Sarcoidosis is a chronic multisystemic inflammatory disease of unknown aetiology with a wide range of highly variable clinical manifestations and unpredictable disease course. Sarcoidosis patients may present with specific organ-related symptoms involving functional impairments, and less specific symptoms. The decision whether and when to treat a sarcoidosis patient with pharmacotherapy depends on two major factors: risk of organ failure and/or death and impairment of quality of life. This decision is complex and not standardized.

RECENT FINDINGS

Glucocorticoids (GCs) are recommended as initial treatment, when needed. Subsequent GC-sparing alternatives frequently follow. Comorbidities or adverse drug reactions (ADRs) from drugs used in sarcoidosis treatment are sometimes very hard to differentiate from symptoms associated with the disease itself, which may cause diagnostic dilemmas. An ideal approach to minimalize ADRs would involve genetic screening prior to prescribing certain 'high-risk drugs' and therapeutic drug monitoring during treatment. Pharmacogenomic testing aims to guide appropriate selection of medicines, with the potential of reducing unnecessary polypharmacy while improving clinical outcomes.

SUMMARY

A multidisciplinary approach to the management of sarcoidosis may avoid unnecessary ADRs. It is important to consider the possibility of drug-induced damage in sarcoidosis, especially if the clinical situation deteriorates after the introduction of a particular drug.

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.

Clinical Features, Histopathology and Differential Diagnosis of Sarcoidosis

Sarcoidosis is a chameleon disease of unknown etiology, characterized by the growth of non-necrotizing and non-caseating granulomas and manifesting with clinical pictures that vary on the basis of the organs that are mainly affected. Lungs and intrathoracic lymph nodes are the sites that are most often involved, but virtually no organ is spared from this disease. Histopathology is distinctive but not pathognomonic, since the findings can be found also in other granulomatous disorders. The knowledge of these findings is important because it could be helpful to differentiate sarcoidosis from the other granulomatous-related diseases. This review aims at illustrating the main clinical and histopathological findings that could help clinicians in their routine clinical practice.

Autophagy and Mitophagy-Related Pathways at the Crossroads of Genetic Pathways Involved in Familial Sarcoidosis and Host-Pathogen Interactions Induced by Coronaviruses

Sarcoidosis is a multisystem disease characterized by the development and accumulation of granulomas, the hallmark of an inflammatory process induced by environmental and/or infectious and or genetic factors. This auto-inflammatory disease mainly affects the lungs, the gateway to environmental aggressions and viral infections. We have shown previously that genetic predisposition to sarcoidosis occurring in familial cases is related to a large spectrum of pathogenic variants with, however, a clustering around mTOR (mammalian Target Of Rapamycin)-related pathways and autophagy regulation. The context of the COVID-19 pandemic led us to evaluate whether such genetic defects may increase the risk of a severe course of SARS-CoV2 infection in patients with sarcoidosis. We extended a whole exome screening to 13 families predisposed to sarcoidosis and crossed the genes sharing mutations with the list of genes involved in the SARS-CoV2 host-pathogen protein-protein interactome. A similar analysis protocol was applied to a series of 100 healthy individuals. Using ENRICH.R, a comprehensive gene set enrichment web server, we identified the functional pathways represented in the set of genes carrying deleterious mutations and confirmed the overrepresentation of autophagy- and mitophagy-related functions in familial cases of sarcoidosis. The same protocol was applied to the set of genes common to sarcoidosis and the SARS-CoV2-host interactome and found a significant enrichment of genes related to mitochondrial factors involved in autophagy, mitophagy, and RIG-I-like (Retinoic Acid Inducible Gene 1) Receptor antiviral response signaling. From these results, we discuss the hypothesis according to which sarcoidosis is a model for studying genetic abnormalities associated with host response to viral infections as a consequence of defects in autophagy and mitophagy processes.