Immunotherapy-induced Addison's disease: A rare, persistent and potentially lethal side-effect

Challenges in autoimmune polyendocrine syndrome type 2 with the full triad induced by anti-programmed cell death 1: a case report and review of the literature

Background

Immune checkpoint inhibitors (ICPis) induce autoimmune diseases, including autoimmune polyendocrine syndrome type 2 (APS-2), which is defined as a combination of at least two of the following endocrinopathies: autoimmune thyroid disease, type 1 diabetes, and Addison's disease. Cases with the full triad are rare. We present a case of an elderly woman who developed APS-2 with the complete triad shortly after starting anti-programmed cell death 1 (anti-PD1) treatment and review the related literature.

Case

A 60-year-old woman, without any personal or family history of autoimmune and endocrine diseases, started the immunotherapy of anti-PD1 (camrelizumab) for squamous cell carcinoma of the urethral meatus. She developed primary hypothyroidism with elevated antibodies to thyroid peroxidase and thyroglobulin after 25 weeks of treatment, and developed primary adrenal insufficiency with adrenal crisis and fulminant type 1 diabetes with ketoacidosis after 45 weeks. Therefore, this patient met the diagnosis of APS-2 and was given multiple hormone replacement including glucocorticoid, levothyroxine and insulin therapy. Continuous improvement was achieved through regular monitoring and titration of the dosage.

Conclusions

Different components of APS-2 may appear at different time points after anti-PD1 administration, and can be acute and life-threatening. A good prognosis can be obtained by appropriate replacement with multiple hormones.

Insights

With the clinical application of ICPis to APS-2, the complexity of its treatment should be paid enough attention.

Endocrine immune-related adverse effects of immune-checkpoint inhibitors

INTRODUCTION

Immune-checkpoint inhibitor therapy modulates the response of the immune system acting against cancer. Two pathways impacted by this kind of treatment are the CTLA4 and the PD-1/PD-L1 pathways. ICI therapy can trigger autoimmune adverse effects, known as immune-related Adverse Events (irAEs).

AREAS COVERED

This review focuses on irAEs which affect the endocrine system. This review elucidates the pathways used by these drugs with a focus on the hypothetical pathogenesis at their basis. In fact, the pathophysiology of irAEs concerns the possibility of an interaction between cellular autoimmunity, humoral immunity, cytokines, chemokines, and genetics. The endocrine irAEs examined are thyroid dysfunctions, immune related-hypophysitis, diabetes, peripheral adrenal insufficiency, and hypoparathyroidism.

EXPERT OPINION

There is still much to investigate in endocrine irAES of checkpoint inhibitors. In the future, checkpoint inhibitors will be increasingly utilized therapies, and therefore it is crucial to find the proper diagnostic-therapeutic program for irAEs, especially as endocrine irAEs are nonreversible and require lifelong replacement therapies.

Endocrine Side Effects in Patients Treated with Immune Checkpoint Inhibitors: A Narrative Review

Checkpoint inhibitors are monoclonal antibodies that elicit an anti-tumor response by stimulating immune system. Their use has improved the treatment of different types of cancer such as melanoma, breast carcinoma, lung, stomach, colon, liver, renal cell carcinoma, and Hodgkin's lymphoma, but several adverse events have been reported. Although the etiology of these effects is not completely understood, an uncontrolled activation of the immune system has been postulated. Indeed, some studies showed a cross reactivity of T cells, which acted against tumor antigens as well as antigens in the tissues of patients who developed immune-related adverse events. Despite the known possibility of developing immune-related adverse events, early diagnosis, monitoring during therapy, and treatment are fundamental for the best supportive care and administration of immune checkpoint inhibitors. The aim of this review is to guide the clinician in early diagnosis, management, and treatment of the endocrinological adverse effects in the major endocrine glands (thyroid, pituitary, adrenal, endocrine pancreas, and parathyroid).

Endocrine-related adverse conditions in patients receiving immune checkpoint inhibition: an ESE clinical practice guideline

Immune checkpoint inhibitors (ICI) have revolutionized cancer treatment but are associated with significant autoimmune endocrinopathies that pose both diagnostic and treatment challenges. The aim of this guideline is to provide clinicians with the best possible evidence-based recommendations for treatment and follow-up of patients with ICI-induced endocrine side-effects based on the Grading of Recommendations Assessment, Development, and Evaluation system. As these drugs have been used for a relatively short time, large systematic investigations are scarce. A systematic approach to diagnosis, treatment, and follow-up is needed, including baseline tests of endocrine function before each treatment cycle. We conclude that there is no clear evidence for the benefit of high-dose glucocorticoids to treat endocrine toxicities with the possible exceptions of severe thyroid eye disease and hypophysitis affecting the visual apparatus. With the exception of thyroiditis, most endocrine dysfunctions appear to be permanent regardless of ICI discontinuation. Thus, the development of endocrinopathies does not dictate a need to stop ICI treatment.

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

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

The Changing Face of Drug-induced Adrenal Insufficiency in the Food and Drug Administration Adverse Event Reporting System

CONTEXT

Adrenal insufficiency (AI) is a life-threatening condition complicating heterogeneous disorders across various disciplines, with challenging diagnosis and a notable drug-induced component.

OBJECTIVE

This work aimed to describe the spectrum of drug-induced AI through adverse drug event reports received by the US Food and Drug Administration (FDA).

METHODS

A retrospective disproportionality analysis reporting trends of drug-induced AI was conducted on the FDA Adverse Event Reporting System (FAERS) (> 15 000 000 reports since 2004). AE reports were extracted from FAERS over the past 2 decades. Interventions included cases containing any of the preferred terms in the Medical Dictionary for Regulatory Activities describing AI, and signals of disproportionate reporting for drugs recorded in 10 or more cases as primary suspect.

RESULTS

We identified 8496 cases of AI: 97.5% serious, 41.1% requiring hospitalization. AI showed an exponential increase throughout the years, with 5282 (62.2%) cases in 2015 to 2020. We identified 56 compounds associated with substantial disproportionality: glucocorticoids (N = 1971), monoclonal antibodies (N = 1644, of which N = 1330 were associated with immune checkpoint inhibitors-ICIs), hormone therapy (N = 291), anti-infectives (N = 252), drugs for hypercortisolism or adrenocortical cancer diagnosis/treatment (N = 169), and protein kinase inhibitors (N = 138). Cases of AI by glucocorticoids were stable in each 5-year period (22%-27%), whereas those by monoclonal antibodies, largely ICIs, peaked from 13% in 2010 to 2015 to 33% in 2015 to 2020.

CONCLUSION

We provide a comprehensive insight into the evolution of drug-induced AI, highlighting the heterogeneous spectrum of culprit drug classes and the emerging increased reporting of ICIs. We claim for the urgent identification of predictive factors for drug-induced AI, and the establishment of screening and educational protocols for patients and caregivers.

Insights Into the Host Contribution of Endocrine Associated Immune-Related Adverse Events to Immune Checkpoint Inhibition Therapy

Blockade of immune checkpoints transformed the paradigm of systemic cancer therapy, enabling substitution of a cytotoxic chemotherapy backbone to one of immunostimulation in many settings. Invigorating host immune cells against tumor neo-antigens, however, can induce severe autoimmune toxicity which in many cases requires ongoing management. Many immune-related adverse events (irAEs) are clinically and pathologically indistinguishable from inborn errors of immunity arising from genetic polymorphisms of immune checkpoint genes, suggesting a possible shared driver for both conditions. Many endocrine irAEs, for example, have analogous primary genetic conditions with varied penetrance and severity despite consistent genetic change. This is akin to onset of irAEs in response to immune checkpoint inhibitors (ICIs), which vary in timing, severity and nature despite a consistent drug target. Host contribution to ICI response and irAEs, particularly those of endocrine origin, such as thyroiditis, hypophysitis, adrenalitis and diabetes mellitus, remains poorly defined. Improved understanding of host factors contributing to ICI outcomes is essential for tailoring care to an individual’s unique genetic predisposition to response and toxicity, and are discussed in detail in this review.

Endocrine immune-related adverse events: Adrenal, parathyroid, diabetes insipidus, and lipoatrophy

Immune checkpoint inhibitors are being prescribed increasingly widely for a range of malignancies. They are effective at treating certain cancers, but also have significant side effects. Evidence suggests that efficacy is greatest in patients who experience one or more immune-related adverse events (irAEs). Common irAEs include skin and hepatic reactions, and a range of immune-related endocrinopathies. These include hypophysitis, thyroid disease, and autoimmune diabetes mellitus, and rarer endocrinopathies such as primary adrenal insufficiency, diabetes insipidus, parathyroid disease, autoimmune polyglandular syndrome, lipodystrophy, and ACTH-dependent Cushing's syndrome. Herein, we review the current literature related to these rarer immunotherapy-induced endocrinopathies.

Polyendocrine Autoimmunity and Diabetic Ketoacidosis Following Anti-PD-1 and Interferon α

Immune checkpoint inhibitor (ICI) therapies are now first-line therapy for many advanced malignancies in adults, with emerging use in children. With increasing ICI use, prompt recognition and optimal management of ICI-associated immune-related adverse events (IRAEs) are critical. Nearly 60% of ICI-treated adults develop IRAEs, which commonly manifest as autoimmune skin, gastrointestinal, and endocrine disease and can be life-threatening. The incidence, presentation, and disease course of spontaneous autoimmune diseases differ between adults and children, but the pattern of pediatric IRAEs is currently unclear. We report a case of a pediatric patient presenting with new onset autoimmune diabetes mellitus and diabetic ketoacidosis during ICI treatment of fibrolamellar hepatocellular carcinoma (FLC). Distinct from spontaneous type 1 diabetes mellitus (T1DM), this patient progressed rapidly and was negative for known β cell autoantibodies. Additionally, the patient was positive for 21-hydroxylase autoantibodies, suggesting development of concomitant adrenal autoimmunity. Current guidelines for the management of IRAEs in adults may not be appropriate for the management of pediatric patients, who may have different autoimmune risks in a developmental context.

Clinical management of immune-related adverse events following immunotherapy treatment in patients with non-small cell lung cancer

The advent of checkpoint blockade-based immunotherapy is rapidly changing the management of lung cancer. Whereas past anticancer drugs' primary toxicity was hematologic, the newer agents have primarily autoimmune toxicity. Thus, it is no longer enough for oncology practitioners to be skilled only in hematology. They must also understand management of autoimmune conditions, leveraging the skills of the rheumatologist, endocrinologist and gastroenterologist in the process. Herein we describe the mechanism of action and toxicities associated with immune checkpoint blockade in patients with lung cancer and provide a framework for management of adverse events.

Post-immunotherapy imaging in lung cancer

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

Immune Checkpoint Inhibitor-Induced Adrenalitis and Primary Adrenal Insufficiency: Systematic Review and Optimal Management

OBJECTIVE

Immune checkpoint inhibitors (ICIs) targeting cytotoxic T-lymphocyte antigen 4 or programmed death 1 and its ligand (programmed death ligand 1) have been approved for the treatment of a variety of cancers. However, ICI therapy is associated with a risk of immune-related adverse events. In this study, we reviewed reported cases of adrenalitis and primary adrenal insufficiency (PAI)-rare but lethal endocrine immune-related adverse events-in patients who underwent ICI therapy.

METHODS

We searched multiple databases (PubMed, Web of Science, Cochrane, and Scopus) up to February 2020 for case reports on adrenalitis and PAI caused by ICIs.

RESULTS

We identified 15 case reports on ICI-induced adrenalitis and PAI and reviewed their clinical presentation, characteristics, immunologic and imaging features, and treatment. We also developed a screening strategy for PAI in patients treated with ICIs.

CONCLUSION

Given the morbidity and mortality associated with acute adrenal crisis, physicians-especially endocrinologists and oncologists-should be aware of this particular risk. PAI caused by autoimmune adrenalitis predominantly occurs in patients treated with programmed death 1 inhibitor monotherapy. PAI often coexists with other endocrinopathies and requires mineralocorticoid as well as glucocorticoid replacement. Even after withdrawal of ICIs, PAI can persist and requires lifelong replacement therapy.

ICPis-Induced Autoimmune Polyendocrine Syndrome Type 2: A Review of the Literature and a Protocol for Optimal Management

CONTEXT

Immune checkpoint inhibitors (ICPis) targeting cytotoxic T-lymphocyte antigen 4 (CTLA-4), programmed cell death protein 1 (PD-1), and its ligand (PD-L1) are now approved to treat a variety of cancers. However, ICPis therapy is associated with a risk of immune-related adverse events (irAEs). Autoimmune polyendocrine syndrome type 2 (APS-2) is a rare endocrine irAE.

EVIDENCE ACQUISITION

Several databases (PubMed, Web of Science, Cochrane Central Registry of Controlled Trials, ClinicalTrials.gov, and Scopus) were searched up to February 18, 2020, for case reports on endocrine irAEs and ICPis. The reported side effects and adverse events of the ICPis therapy in the US Food and Drug Administration (FDA) and European Medicines Agency (EMA) adverse events pharmacovigilance registries are also included.

EVIDENCE SYNTHESIS

Here, we provide an overview of all published and reported cases (n = 30) of ICPis-induced APS-2. We summarize the clinical characteristics, autoantibodies, human leukocyte antigen (HLA) genotypes, and therapies and propose an APS-2 screening strategy.

CONCLUSIONS

Given the life-threatening risks of endocrine dysfunction if it is not promptly recognized (such as diabetic ketoacidosis and acute adrenal crisis), physicians (especially endocrinologists and oncologists) should be familiar with APS-2. After diagnosis of an autoimmune disease induced by ICPis (especially PD-1 inhibitors), patients with a high-risk HLA allele (HLA-DR4) require close monitoring for the development of APS-2.

Reversible primary adrenal insufficiency related to anti-programmed cell-death 1 protein active immunotherapy: Insight into an unforeseen outcome of a rare immune-related adverse event

The immune checkpoint inhibitors (ICPi) revolutionize the cancer therapeutics, though not being devoid of toxicity. The immune-related primary adrenal insufficiency (PAI) is a rare, yet potentially life-threatening, adverse event, posing diagnostic and therapeutic challenges. We report the first case of reversible PAI related to nivolumab (programmed cell-death 1 protein inhibitor) in a 42-year-old male with metastatic rectal adenocarcinoma. PAI manifested as profound fatigue, disorientation, hypotension, hyperpigmentation of palmar creases, and hyponatremia without hyperkalemia 16 weeks after initiation of nivolumab. Due to impending adrenal crisis, intravenous stress doses of hydrocortisone and hydration with normal saline were initiated. When the state of patient was stabilized, PAI was confirmed through 250 μg Synacthen test 24 h after temporary cessation of hydrocortisone. Hydrocortisone was fixed at maintenance dose, while mineralocorticoid substitution was not required. PAI was ascribed to nivolumab based on history, physical examination, and laboratory work-up with emphasis on positivity of anti-21-hydroxylase antibodies and exclusion of other causes of PAI by normal imaging of adrenal glands on computed tomography (CT). Reevaluation of adrenal function during follow up demonstrated complete recovery. A review of literature concerning the immune-related PAI indicated that the complete recovery of adrenal function, the normal CT imaging, and the positivity of anti-21-hydroxylase antibodies observed in our patient are exceptional findings of immune-related PAI. Finally, heightened suspicion of immune-related PAI in case of hyponatremia without hyperkalemia and constant vigilance for diagnosis of rare, but real, reversibility of immune-related PAI are of paramount importance.

Immune Checkpoint Inhibitor-Associated Primary Adrenal Insufficiency: WHO VigiBase Report Analysis

BACKGROUND

Immune checkpoint inhibitors (ICIs) have transformed cancer therapy but may also trigger autoimmune adverse drug reactions (ADRs) referred to as immune-related adverse events (irAEs). Although endocrinopathies are among the most common form of irAEs, primary adrenal insufficiency (PAI) is infrequent and has only been published in case reports. The aim of this study was to identify and characterize the main features of PAI-irAE.

MATERIALS AND METHODS

Suspected PAI-irAE cases were identified using VigiBase, the World Health Organization's pharmacovigilance database of individual case safety reports.

RESULTS

From September 2, 2008, through October 5, 2018, a total of 50,108 ICI-associated ADRs were reported. Since 2008, there were 451 cases of PAI-irAE identified of which 45 were "definite PAI" and 406 "possible PAI." Patients were mainly male (58.1%) with a median age of 66 years (range, 30-95). Indications of ICI were predominantly for melanoma (41.2%) and lung cancer (28.6%). The majority of patients were treated with ICI monotherapy (nivolumab: 44.3%, pembrolizumab: 11.7%, ipilimumab: 23.6%), and 17.9% were treated with ICI combination therapy. These events occurred with a median time to onset of 120 days (range, 6-576). ICI-associated PAI was associated with significant morbidity (≥90% severe) and mortality (7.3%). Fatality rates were similar in the subgroups of combination therapy versus monotherapy. There were no relevant differences in clinical or demographical characteristics and outcomes between "definite" versus "possible" PAI group.

CONCLUSION

Our study represents the largest clinical description and characterization of PAI-irAE. Although ICI-associated PAI is a rare adverse event, early recognition is important to implement corticosteroid treatment. Further studies are required to elucidate risk factors and reversibility of this rare but severe irAE. Clinical trial identification number. NCT03492242 IMPLICATIONS FOR PRACTICE: Immune checkpoint inhibitor (ICI)-associated primary adrenal insufficiency (PAI) is a rare adverse event that is important to recognize because it may be severe and life-threatening, requiring emergent and often lifelong hormonal replacement therapy. Awareness regarding this ICI-related endocrinopathy is strongly encouraged among clinicians in addition to patient education about common PAI symptoms that should prompt urgent medical evaluation. In clinical practice, close monitoring and investigation for PAI is crucial to allow for early management and to further define the pathophysiology and prognosis of ICI-PAI. Corticotrophin (adrenocorticotrophic hormone) circulating level evaluation may be often lacking but should be considered as part of the diagnostic workup to differentiate PAI from secondary (central) adrenal insufficiency.

Endocrine adverse events related with immune checkpoint inhibitors: an update for clinicians

Designated as scientific breakthrough of current decade, immune checkpoint inhibitors attenuate the cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) and the programmed cell death 1 (PD-1)/ligand 1 (PD-L1) pathways, depriving cancer cells of a key strategy of evasion from immunosurveillance. The reinvigoration of immune response translates into clinical success, inevitably entwined with a novel constellation of immune-related adverse events. The present review dissects the endocrine immune-related adverse events, emphasizing their unique profile featured by unpredictable onset, irreversibility, nonspecific symptoms, wide clinical spectrum and sophisticated diagnostic work-up. Guidelines advocate individualized decision-making process guided by clinicians' judgement. Future perspective should be governed by five principles - prevention, anticipation, detection, treatment, monitoring - aiming to gain the optimal profit diminishing immunotoxicity.

Biointerface engineering nanoplatforms for cancer-targeted drug delivery

Over the past decade, nanoparticle-based therapeutic modalities have become promising strategies in cancer therapy. Selective delivery of anticancer drugs to the lesion sites is critical for elimination of the tumor and an improved prognosis. Innovative design and advanced biointerface engineering have promoted the development of various nanocarriers for optimized drug delivery. Keeping in mind the biological framework of the tumor microenvironment, biomembrane-camouflaged nanoplatforms have been a research focus, reflecting their superiority in cancer targeting. In this review, we summarize the development of various biomimetic cell membrane-camouflaged nanoplatforms for cancer-targeted drug delivery, which are classified according to the membranes from different cells. The challenges and opportunities of the advanced biointerface engineering drug delivery nanosystems in cancer therapy are discussed.

Epidemiology, pathogenesis, and diagnosis of Addison's disease in adults

BACKGROUND

Addison's disease (AD) is a rare disorder and among adult population in developed countries is most commonly caused by autoimmunity. In contrast, in children genetic causes are responsible for AD in the majority of patients.

PURPOSE

This review describes epidemiology, pathogenesis, genetics, natural history, clinical manifestations, immunological markers and diagnostic strategies in patients with AD. Standard care treatments including the management of patients during pregnancy and adrenal crises consistent with the recent consensus statement of the European Consortium and the Endocrine Society Clinical Practice Guideline are described. In addition, emerging therapies designed to improve the quality of life and new strategies to modify the natural history of autoimmune AD are discussed.

CONCLUSIONS

Progress in optimizing replacement therapy for patients with AD has allowed the patients to lead a normal life. However, continuous education of patients and health care professionals of ever-present danger of adrenal crisis is essential to save lives of patients with AD.

French Endocrine Society Guidance on endocrine side effects of immunotherapy

The management of cancer patients has changed due to the considerably more frequent use of immune checkpoint inhibitors (ICPIs). However, the use of ICPI has a risk of side effects, particularly endocrine toxicity. Since the indications for ICPI are constantly expanding due to their efficacy, it is important that endocrinologists and oncologists know how to look for this type of toxicity and how to treat it when it arises. In view of this, the French Endocrine Society initiated the formulation of a consensus document on ICPI-related endocrine toxicity. In this paper, we will introduce data on the general pathophysiology of endocrine toxicity, and we will then outline expert opinion focusing primarily on methods for screening, management and monitoring for endocrine side effects in patients treated by ICPI. We will then look in turn at endocrinopathies that are induced by ICPI including dysthyroidism, hypophysitis, primary adrenal insufficiency and fulminant diabetes. In each chapter, expert opinion will be given on the diagnosis, management and monitoring for each complication. These expert opinions will also discuss the methodology for categorizing these side effects in oncology using 'common terminology criteria for adverse events' (CTCAE) and the difficulties in applying this to endocrine side effects in the case of these anti-cancer therapies. This is shown in particular by certain recommendations that are used for other side effects (high-dose corticosteroids, contraindicated in ICPI for example) and that cannot be considered as appropriate in the management of endocrine toxicity, as it usually does not require ICPI withdrawal or high-dose glucocorticoid intake.

Sick sinus syndrome associated with anti-programmed cell death-1

Background

Use of anti-programmed cell death-1 (anti-PD-1) has been successful in treating many types of cancers. Despite its promising efficacy, immune-related adverse events are still a major concern. Immune-related cardiotoxicity, which is rare but fatal, has recently become a focus of attention. Cardiotoxicities including myocarditis, cardiomyopathy, cardiac fibrosis, heart block and cardiac arrest have been reported. Of these toxicities, myocarditis is often accompanied by dysrhythmia. The presentation of sick sinus syndrome as an immune-related adverse event has not yet been reported. Here, we reported the first case of sick sinus syndrome, a rare toxicity induced by anti-PD-1.

Case presentation

A 42-year-old male patient who had metastatic hepatocellular carcinoma failed treatment with sorafenib. Pembrolizumab at a fixed dose of 100 mg every three weeks was given. His heart rate gradually slowed down and he presented sick sinus syndrome with a lowest heart rate of 38 bpm after six cycles of pembrolizumab. He denied chest tightness, cold sweating, palpitation and dyspnea. Lab data including cardiac enzyme, electrolytes and thyroid function were all within a normal range. Simultaneously, he complained of fatigue, dizziness and anorexia with hypotension. Lab data revealed low cortisol and ACTH levels. Anti-PD-1 induced adrenal insufficiency was suspected. Low-dose cortisone (12.5 mg) was prescribed, and the patient’s symptoms, hypotension and sick sinus syndrome showed rapid improvement. Cortisone was gradually titrated and discontinued three weeks later. His sick sinus syndrome did not relapse and the cortisol and ACTH level returned to normal.

Conclusions

Sick sinus syndrome caused by anti-PD-1 treatment is a rare adverse event. With the development of sick sinus syndrome, myocarditis should be the first differential diagnosis because of its lethality. From this case, we learned that sick sinus syndrome may be a presentation of immune- or adrenal insufficiency-mediated sinus node dysfunction, both could be reversed with a glucocorticoid supplement.

Expert opinions on adrenal complications in immunotherapy

Primary adrenal insufficiency during immunotherapy is rare and does not warrant systematic screening during treatment. It should be suspected in case of typical clinical and biological presentation, but also in case of subclinical presentation with impaired general health status and/or hyponatremia. Diagnosis is based on low cortisol levels, measured at any time in case of emergency or else at 8 am, associated to elevated ACTH to rule out pituitary origin. Secondarily, anti-21-hydroxylase antibody assay may be performed, with screening for mineralocorticoid deficiency. Imaging is recommended, although not urgent, to screen for "adrenalitis" or adrenal atrophy and rule out differential diagnosis of adrenal metastasis. Primary adrenal insufficiency during immunotherapy is a medical emergency requiring hydrocortisone replacement adapted to the clinical and biological context. Management by an endocrinologist is essential, in order to adapt hydrocortisone and fludrocortisone replacement therapy and to educate both patient and oncologist in hydrocortisone dose adaptation. Current data suggest that treatment needs to be life-long, even after termination of immunotherapy. The present article does not deal with secondary adrenal insufficiency, which is included in the section on "Pituitary toxicity".