Immune checkpoint inhibitor related hypophysitis: diagnostic criteria and recovery patterns

Managing Select Immune-Related Adverse Events in Patients Treated with Immune Checkpoint Inhibitors

The increased use of immune checkpoint inhibitors (ICIs) across cancer programs has created the need for standardized monitoring and management of immune-related adverse events (irAEs). Delayed recognition without appropriate treatment can have serious and life-threatening consequences. The management of irAEs presents a unique set of challenges that must be addressed at a multidisciplinary level. Although various national and international guidelines and working groups provide high-level recommendations for the management of irAEs, practical guidance is lacking. Furthermore, timely collaboration between specialists requires institutional protocols that enable the early recognition, assessment, and treatment of irAEs. Such protocols should be developed by institution specialists and include algorithms for all healthcare providers involved in the care of patients treated with ICIs. At William Osler Health System in Brampton, Ontario, practical step-by-step multidisciplinary treatment approaches with recommendations for the management of irAEs were developed in collaboration with experts across Canada. Here, we provide an in-depth description of the approaches, outlining baseline investigations prior to the initiation of ICIs, as well as the monitoring and management of irAEs based on symptoms, severity, and involved organ systems. We encourage other centres to adapt and modify our approaches according to their specific needs and requirements.

An Update on Advances in Hypopituitarism: Etiology, Diagnosis, and Current Management

This article provides an updated review of hypopituitarism (HP), an endocrine disorder characterized by a deficiency of one or more pituitary hormones. The various etiologies are reviewed, including pituitary neuroendocrine tumors (PitNETs), hypothalamic lesions, genetic mutations, and acquired factors such as head trauma, medications, neoplasms, and infiltrative diseases. It is noted that PitNETs are responsible for approximately half of the cases in adults, whereas in children the causes are predominantly congenital. Diagnosis is based on clinical evaluation and hormonal testing, with identification of the specific hormonal deficiencies essential for effective treatment. Laboratory tests present challenges and limitations that must be understood and addressed. Hormone replacement therapy is the mainstay of treatment, significantly improving patients' quality of life. It is important to know the possible interactions between hormone replacement therapies in HP. Recent advances in understanding the pathophysiology of HP and the importance of a multidisciplinary approach to the management of associated complications are discussed. This article emphasizes the need for comprehensive evaluation and continuous follow-up to optimize outcomes in patients with HP and highlights the importance of ongoing research to improve diagnostic and treatment strategies.

Differences in checkpoint-inhibitor-induced hypophysitis: mono- versus combination therapy induced hypophysitis

Objective

Immune checkpoint inhibitors (ICIs) are revolutionary in oncology but may cause immune-related (IR) side effects, such as hypophysitis. Treatment with anti-PD-(L)1, anti-CTLA-4 or anti-CLTA-4/PD-1 may induce hypophysitis, but little is known about the differences in clinical presentation or need for different treatment. We analyzed the differences of anti-PD-(L)1, anti-CTLA-4 and anti-CTLA-4/PD-1 induced hypophysitis.

Methods

retrospective analysis of 67 patients (27 anti-PD-(L)1, 6 anti-CLTA-4 and 34 anti-CTLA-4/PD-1 induced hypophysitis).

Results

The median time between starting ICIs and IR-hypophysitis was longer after anti-PD(L)-1) therapy (22 weeks versus 11 and 14 weeks after anti-CTLA-4 and anti-CTLA-4/PD-1 therapy, respectively). The majority of patients (>90%), presented with atypical complaints such as fatigue, nausea, and muscle complaints. Headache, TSH or LH/FSH deficiency were more common in anti-CTLA-4 and anti-CLTA-4/PD-1 versus anti-PD-(L)1 induced hypophysitis (83% and 58% versus 8%, 67% and 41% versus 11%, and 83% and 48% versus 7%, respectively). Pituitary abnormalities on MRI (hypophysitis or secondary empty sella syndrome) were only seen in patients receiving anti-CTLA-4 or anti-CTLA-4/PD-1 therapy. Recovery from TSH, LH/FSH and ACTH deficiency was described in 92%, 70% and 0% of patients after a mean period of 14 and 104 days, respectively, and did not differ between patients who did or did not receive high-dose steroids.

Conclusion

The clinical presentation of IR-hypophysitis varies depending on the type of ICIs. MRI abnormalities were only seen in anti-CTLA-4 or anti-CTLA-4/PD-1 induced hypophysitis. Endocrine recovery is seen for LH/FSH and TSH deficiency but not for ACTH deficiency, irrespective of the corticosteroid dose.

Hypopituitarism

Partial or complete deficiency of anterior or posterior pituitary hormone production leads to central hypoadrenalism, central hypothyroidism, hypogonadotropic hypogonadism, growth hormone deficiency, or arginine vasopressin deficiency depending on the hormones affected. Hypopituitarism is rare and likely to be underdiagnosed, with an unknown but rising incidence and prevalence. The most common cause is compressive growth or ablation of a pituitary or hypothalamic mass. Less common causes include genetic mutations, hypophysitis (especially in the context of cancer immunotherapy), infiltrative and infectious disease, and traumatic brain injury. Clinical features vary with timing of onset, cause, and number of pituitary axes disrupted. Diagnosis requires measurement of basal circulating hormone concentrations and confirmatory hormone stimulation testing as needed. Treatment is aimed at replacement of deficient hormones. Increased mortality might persist despite treatment, particularly in younger patients, females, and those with arginine vasopressin deficiency. Patients with complex diagnoses, pregnant patients, and adolescent pituitary-deficient patients transitioning to adulthood should ideally be managed at a pituitary tumour centre of excellence.

Endocrinopathies Associated With Immune Checkpoint Inhibitor Use

OBJECTIVE

To provide a clinical approach towards immune checkpoint inhibitor (ICI)-associated endocrinopathies, their link with cancer outcomes, factors which differentiate them from other immune related adverse events, and health systems innovation to improve care for these patients.

METHODS

A literature search for articles pertaining to ICIs and endocrinopathies was performed and supplemented by expert opinions of the authors.

RESULTS

While immune related adverse events can affect almost any organ, they frequently target the endocrine glands, most commonly thyroid. Different classes of ICIs have varying frequencies of endocrinopathies related to hypophysitis, thyroiditis, diabetes mellitus, and rarely hypoadrenalism and hypoparathyroidism. ICI-associated endocrinopathies share some features with classic endocrine autoimmunity but appear to be a distinct entity. They can be challenging to diagnose and manage due to nonspecific clinical features, use of exogenous glucocorticoids, and at times rapid and severe hormone deficiency. The role of anti-inflammatory high-dose glucocorticoids is minimal, and the ICI does not usually require permanent discontinuation. ICI-associated endocrinopathies usually cause permanent hormone deficiency necessitating long-term management and patient engagement. ICI-thyroiditis has been associated with improved survival, while other endocrinopathies have not shown a significant association with outcomes in cancer patients receiving ICIs. Oncoendocrinology teams can improve the care of patients with ICI-associated endocrinopathies.

CONCLUSION

This narrative review provides guidance to clinicians prescribing ICIs and those managing ICI-associated endocrinopathies, and complements the frameworks provided by major scientific societies in this field.

Iatrogenic adrenal insufficiency in adults

Iatrogenic adrenal insufficiency (IAI) is the most common form of adrenal insufficiency in adult patients, although its overall exact prevalence remains unclear. IAI is associated with adverse clinical outcomes, including adrenal crisis, impaired quality of life and increased mortality; therefore, it is imperative that clinicians maintain a high index of suspicion in patients at risk of IAI to facilitate timely diagnosis and appropriate management. Herein, we review the major causes, clinical consequences, diagnosis and care of patients with IAI. The management of IAI, particularly glucocorticoid-induced (or tertiary) adrenal insufficiency, can be particularly challenging, and the provision of adequate glucocorticoid replacement must be balanced against minimizing the cardiometabolic effects of excess glucocorticoid exposure and optimizing recovery of the hypothalamic-pituitary-adrenal axis. We review current treatment strategies and their limitations and discuss developments in optimizing treatment of IAI. This comprehensive Review aims to aid clinicians in identifying who is at risk of IAI, how to approach screening of at-risk populations and how to treat patients with IAI, with a focus on emergency management and prevention of an adrenal crisis.

Clinical and translational attributes of immune-related adverse events

With immune checkpoint inhibitors (ICIs) becoming the mainstay of treatment for many cancers, managing their immune-related adverse events (irAEs) has become an important part of oncological care. This Review covers the clinical presentation of irAEs and crucial aspects of reversibility, fatality and long-term sequelae, with special attention to irAEs in specific patient populations, such as those with autoimmune diseases. In addition, the genetic basis of irAEs, along with cellular and humoral responses to ICI therapy, are discussed. Detrimental effects of empirically used high-dose steroids and second-line immunosuppression, including impaired ICI effectiveness, call for more tailored irAE-treatment strategies. We discuss open therapeutic challenges and propose potential avenues to accelerate personalized management strategies and optimize outcomes.

PD-1/PD-L1 inhibitors associated hypophysitis: An analysis from the FAERS database and case reports

To get a thorough understanding of PD-1/L1 inhibitor-related hypophysitis (PD-1/L1-irH), we utilized a combination of disproportionality analysis and case analysis to comprehensively characterize the clinical features of PD-1/L1-irH. Significant signals of hypophysitis were detected for all PD-1/PD-L1 inhibitors in the FAERS (FDA Adverse Event Reporting System). As revealed by both FAERS and the case analysis, PD-1/L1-irH occurred more commonly in males, PD-1 inhibitors users and patients older than 65 years. The median onset time was 101 days in FAERS and 8 cycles in the case analysis. In the case analysis, eight late-onset PD-1/L1-irHs occurred even after a discontinuation of several months (4-15 months). As revealed in FAERS, the outcome of PD-1/L1-irH tended to be poor, generally resulting in 64.66% hospitalization and 12.59% death. Fatigue was the most prominent symptom of PD-1/L1-irH, followed by anorexia, hyponatremia, and hypotension, as revealed by the analysis of 84 cases. Meanwhile isolated adrenocorticotropic (ACTH) deficiency was particularly prevalent for PD-1/L1-irH (85.71%), while gonadal hormones or posterior pituitary hormones deficiencies were rare. Glucocorticoids were administered to almost all cases (81/84), with a physiologic or stress dosage in 61.9% of cases, and a high-dose in 26.2% of cases. Most cases (58.3%) showed a favorable tumor response before diagnosis of PD-1/L1-irH. PD-1/L1-irH may occur throughout the whole therapy period even after discontinuation. Clinicians should pay more attention to PD-1 inhibitor users, males and older patients. Early diagnosis and prompt managements are crucial for PD-1/L1-irH as its potentially life-threatening nature.

Adrenal crisis mainly manifested as recurrent syncope secondary to tislelizumab: a case report and literature review

As an immune checkpoint inhibitor (ICI), tislelizumab is an anti-programmed cell death protein 1 (PD-1) drug. With the extensive application of ICIs, there is an ever-increasing proportion of immune-related adverse events (irAEs) in clinical settings, some of which may even be life-threatening. Herein, we present a patient with tislelizumab-induced adrenal crisis. The main clinical manifestation was recurrent syncope accompanied by high-grade fever. Timely identification and hormone replacement therapy helped the patient overcome the crisis well. Finally, the patient discontinued tislelizumab and switched to antibody-drug conjugate (ADC) therapy. We report this case to improve our understanding of this situation, identify this kind of disease, and prevent adrenal crisis in time. Eventually, limiting toxicities reduces the interruption of immunotherapy. Since irAEs are multisystem damage with more non-specific symptoms, except for oncologists, general practitioners who endorse the need for taking a holistic approach to the patient should play a vital role in the management of cancer treatment.

Good Gone Bad: Complications of Chemotherapy, Immunotherapy, and Radiotherapy on the CNS

With recent advancements in cancer therapy, especially immunotherapy, overall survival of many cancers has increased and patient toxicity has been reduced. However, many complications of traditional cancer therapy are still prevalent and complications of novel therapies are just beginning to appear. The neuroradiologist may be the first to visualize signs of these complications on imaging. This article describes the notable imaging findings of several unique and characteristic complications of CNS cancer therapy, including toxicities of chemotherapies, immunotherapies, and radiotherapy. Complications of chemotherapeutic agents covered include methotrexate-induced and disseminated necrotizing leukoencephalopathy, and chemotherapy-induced myelopathy. Immunotherapy complications included are Tacrolimus-related Optic Neuropathy, Rituximab and Immune reconstitution inflammatory syndrome-associated Progressive Multifocal Leukoencephalopathy, Bevacizumab-associated late radiation-induced neurotoxicity, and Ipilimumab-induced hypophysitis. Lastly, radiation-induced neurotoxicities are covered, including myelopathy, radiation necrosis, cerebral atrophy, leukoencephalopathy, optic neuropathy, mineralizing microangiopathy, stroke-like migraine attacks, osteonecrosis, and vasculopathies. Neuroradiologists will increasingly encounter patients who have undergone treatment with more than 1 therapeutic modality, resulting in overlapping findings as well. Recognition of the common complications of these therapies on imaging is critical to minimizing the effects of these potential short- and long-term complications.

Hypophysitis Induced by Sintilimab in the Treatment of Bladder Cancer: A Case Report

BACKGROUND

Immune checkpoint inhibitors (ICIs), as novel antitumor drugs, have been widely used in the clinic and have shown good antitumor effects. However, their widespread use has also led to the emergence of various immune-related adverse events (IrAEs). Hypophysitis is a rare but serious IrAE. Due to its complex and changeable clinical manifestations, hypophysitis may be easily overlooked, leading to delayed diagnosis and treatment.

CASE PRESENTATION

A 68-year-old male patient was diagnosed with bladder cancer (T2bNXM0) in October 2021. He received two cycles of immunotherapy with sintilimab and chemotherapy with gemcitabine and cisplatin (GC). One month after the second treatment, he gradually developed recurrent fever, anorexia, drowsiness, and delirium. Laboratory examination revealed hyponatremia, decreased adrenocorticotropic hormone, and hypocortisolemia. The pituitary MRI showed no abnormality. The patient was diagnosed with immunotherapy-induced hypophysitis (IH) caused by sintilimab, leading to downstream endocrine disorders. With hormone replacement therapy, he was in a good mood, had a good appetite, and made an overall recovery.

CONCLUSION

Immunotherapy-induced hypophysitis (IH) can result in a severe adrenal crisis, and prompt recognition and diagnosis are crucial. Clinicians must remain vigilant for the possibility of IH in patients who exhibit recurrent fever, anorexia, cognitive decline, and personality changes following ICI treatment. It is imperative to consider this diagnosis early to initiate appropriate management promptly.

Updates in toxicities associated with immune checkpoint inhibitors

INTRODUCTION

Immune checkpoint inhibitors (ICIs) have become a pillar of treatment for numerous cancers with increasing use in combination with other ICIs and in earlier stages of disease treatment. Although effective, ICI use is accompanied by a milieu of potentially bothersome or even life-threatening toxicities known as immune-related adverse events (irAEs), necessitating careful monitoring and early intervention.

AREAS COVERED

In this review, we provide an overview of recent advances surrounding toxicity pathophysiology and treatment in the context of relevant organ systems. An emphasis on current treatments by toxicity, as well as updates on steroid-refractory toxicities, chronic toxicities, and biomarkers will be a focus of this update on the current understanding of irAEs.

EXPERT OPINION

ICI toxicities are a major limitation on the deployment of multi-agent ICI regimens and are thus a major priority to understand, treat, and prevent. Recent developments have led to greater understanding of the pathophysiology of these events, which may lead to improved prevention or mitigation strategies. Further, early studies have also suggested steroid-sparing approaches that may be useful. Ultimately, preventing and managing irAEs will be a key goal toward successful ICI treatment across a broader range of patients with cancer.

Recent Therapeutic Advances in Pituitary Carcinoma

Pituitary carcinoma (PC) is a rare, aggressive malignancy that comprises 0.1-0.2% of all pituitary tumors. PC is defined anatomically as a pituitary tumor that metastasizes outside the primary intrasellar location as noncontiguous lesions in the central nervous system or as metastases to other organs. Similar to pituitary adenoma, PC originates from various cell types of the pituitary gland and can be functioning or nonfunctioning, with the former constituting the majority of the cases. Compression of intricate skull-based structures, excessive hormonal secretion, impaired pituitary function from therapy, and systemic metastases lead to debilitating symptoms and a poor survival outcome in most cases. PC frequently recurs despite multimodality treatments, including surgical resection, radiotherapy, and biochemical and cytotoxic treatments. There is an unmet need to better understand the pathogenesis and molecular characterization of PC to improve therapeutic strategies. As our understanding of the role of signaling pathways in the tumorigenesis of and malignant transformation of PC evolves, efforts have focused on targeted therapy. In addition, recent advances in the use of immune checkpoint inhibitors to treat various solid cancers have led to an interest in exploring the role of immunotherapy for the treatment of aggressive refractory pituitary tumors. Here, we review our current understanding of the pathogenesis, molecular characterization, and treatment of PC. Particular attention is given to emerging treatment options, including targeted therapy, immunotherapy, and peptide receptor radionuclide therapy.

Endocrine Dysfunction From Immune Checkpoint Inhibitors: Pearls and Pitfalls in Evaluation and Management

Immune checkpoint inhibitors (ICPis) have proven extremely efficacious in cancer therapy but also lead to a plethora of immune-related adverse events (irAEs). The endocrine irAEs are not only quite common but also may pose a challenge to the clinician while managing a patient with cancer treated with ICPis. The clinical features of endocrine dysfunction are usually nonspecific and may overlap with concurrent illnesses, underlying the importance of accurate hormone testing and efforts toward case-finding. The management of endocrine irAEs is unique in the focus being on hormone replacement rather than curtailing the autoimmune process. Although the management of thyroid irAEs appears straightforward, adrenal insufficiency and insulin-dependent diabetes can be life-threatening if not promptly recognized and treated. This clinical review synthesizes the studies to provide pearls and pitfalls in the evaluation and management of endocrine irAEs with specific reference to guidelines from oncologic societies.

Autoantibodies involved in primary and secondary adrenal insufficiency following treatment with immune checkpoint inhibitors

Primary and secondary adrenal insufficiency (AI) are commonly known immune-related adverse events following treatment with immune checkpoint inhibitors (ICIs), and are clinically relevant due to their morbidity and potential mortality. For this reason, upfront identification of patients susceptible for ICI-induced AI could be a step in improving patient's safety. Multiple studies have focused on the identification of novel biomarkers for ICI-induced AI, including autoantibodies, which may be involved in ICI-induced AI as a result of the T-cell-mediated activation of autoreactive B cells. This review highlights the currently described autoantibodies that may be involved in either primary [e.g. anti-21-hydroxylase, anti-17α-hydroxylase, anti-P450scc, anti-aromatic L-amino acid decarboxylase (AADC), anti-interferon (IFN)α and anti-IFNΩ] or secondary AI [e.g. anti-guanine nucleotide-binding protein G(olf) subunit alpha (GNAL), anti-integral membrane protein 2B (ITM2B), anti-zinc finger CCHC-type containing 8 (ZCCHC8), anti-pro-opiomelanocortin (POMC), anti-TPIT (corticotroph-specific transcription factor), anti-pituitary-specific transcriptional factor-1 (PIT-1) and others], and discusses the current evidence concerning their role as biomarker for ICI-induced AI. Standardized autoantibody measurements in patients (to be) treated with ICIs would be a clinically accessible and patient-friendly screening method to identify the patients at risk, and could change the management of ICI-induced AI.

APPROACH TO THE PATIENT WITH IMMUNE CHECKPOINT INHIBITOR-ASSOCIATED ENDOCRINE DYSFUNCTION

Immune checkpoint inhibitors (ICI) are cancer therapies that are approved in at least 19 different cancers. They function by stimulating immune cell responses against cancer, and their toxicities comprise a host of autoinflammatory syndromes that may impact any organ system. Endocrine toxicities occur in as high as 25-50% of ICI recipients, depending on the treatment regimen used. These toxicities vary in severity from mild, asymptomatic cases of subclinical hypothyroidism to severe, fatal cases of adrenal crisis, thyroid dysfunction, or diabetic ketoacidosis. Thus, timely recognition and treatment is critical. Herein, we present clinical cases of ICI-induced thyroid dysfunction, hypophysitis, and insulin-dependent diabetes mellitus. We use these cases to discuss the screening, diagnosis, and management of ICI-associated endocrine dysfunction.

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.

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.

Routine Screening for Central and Primary Adrenal Insufficiency during Immune-Checkpoint Inhibitor Therapy: An Endocrinology Perspective for Oncologists

Background: Immune checkpoint inhibitor (ICI)-associated hypothalamic–pituitary–adrenal axis disruption can lead to hypocortisolism. This is a life-threatening but difficult to diagnose condition, due to its non-specific symptoms that overlap with symptoms of malignancy. Currently, there is no consensus on how to best screen asymptomatic patients on ICI therapy for hypophysitis with serum cortisol. Methods: A retrospective chart review of patients treated with ICI in a tertiary care centre was conducted to assess the rate of screening with cortisol and whether this had an impact on diagnosis of ICI-hypophysitis in the preclinical stage. Patients were identified as having hypophysitis with an adrenocorticotropin hormone (ACTH) deficiency based on chart review of patients with cortisol values ≤ 140 nmol/L (≤5 mcg/dL). We also assessed what proportion of cortisol values were drawn at the correct time for interpretation (between 6 AM and 10 AM). Results: Two hundred and sixty-five patients had 1301 cortisol levels drawn, only 40% of which were drawn correctly (between 6 and 10 AM). Twenty-two cases of hypophysitis manifesting with ACTH deficiency were identified. Eight of these patients were being screened with cortisol following treatment and were detected in the outpatient setting. The remaining 14 patients were not screened and were diagnosed when symptomatic, after an emergency room visit or hospital admission. Sixty percent of the cortisol tests were uninterpretable as they were not drawn within the appropriate time window. Conclusion: Measuring morning serum cortisol in asymptomatic patients on ICI therapy is a fast and inexpensive way to screen for hypophysitis and should become the standard of care. Random serum cortisol measurement has no clinical value. Education needs to be provided on when to correctly perform the test and how to interpret it and we provide an algorithm for this purpose. The adoption and validation of such an algorithm as part of routine practice could significantly reduce morbidity and mortality in patients, especially as ICI therapy is becoming increasingly commonplace.

Hypophysitis

OBJECTIVE

Hypophysitis is considered a rare inflammatory disease of the pituitary gland. For a long time, primary autoimmune hypophysitis has stood out as the most relevant type of hypophysitis. However, with the advent of immunotherapy for the treatment of malignancies and identification of hypophysitis as an immune-related adverse event, hypophysitis has garnered increasing interest and recognition. Therefore, awareness, early recognition, and appropriate management are becoming important as the indication for immunomodulatory therapies broaden.

METHODS

In this review, we discuss the epidemiology, diagnosis, and treatment of hypophysitis with a focus on recent data and highlight subtypes of particular interest while recognizing the gaps in knowledge that remain.

RESULTS

Regardless of cause, symptoms and signs of hypophysitis may be related to mass effect (headache and visual disturbance) and hormonal disruption that warrant prompt evaluation. In the vast majority of cases, a diagnosis of hypophysitis can be made presumptively in the appropriate clinical context with radiologic findings consistent with hypophysitis and after the exclusion of other causes.

CONCLUSION

Although subtle differences currently exist in management and outcome expectations between primary and secondary causes of hypophysitis, universally, treatment is aimed at symptom management and hormonal replacement therapy.

Thyroid Dysfunction from Treatments for Solid Organ Cancers

In recent years, cancer care has been transformed by immune-based and targeted treatments. Although these treatments are effective against various solid organ malignancies, multiple adverse effects can occur, including thyroid dysfunction. In this review, the authors consider treatments for solid organ cancers that affect the thyroid, focusing on immune checkpoint inhibitors, kinase inhibitors, and radioactive iodine-conjugated treatments (I-131-metaiodobenzylguanidine). They discuss the mechanisms causing thyroid dysfunction, provide a framework for their diagnosis and management, and explore the association of thyroid dysfunction from these agents with patient survival.

Immune checkpoint inhibitor-related hypophysitis

Immune checkpoint inhibitors (ICIs) have been recently proposed as a strategy for treating anti-malignant neoplasms. However, this treatment leads to immune-related adverse events (irAEs) such as autoimmune endocrinopathy. Early diagnosis and appropriate treatment of ICI-related hypophysitis are essential as it can manifest as a life-threatening condition due to an adrenal crisis. In this review, we summarize the pathogenesis, risk factors, diagnostic processes, clinical characteristics, and its current management. In particular, we discuss the different aspects of anti-CTLA-4 antibody-related and anti-PD-1/anti-PD-L1 antibody-related hypophysitis. We also propose key points for early detection and diagnosis by identifying the target group that should be monitored more carefully. Specific methods of hormone replacement therapy have also been described. We hope that this review will lead to a better understanding and management of this rare but serious condition during cancer treatment and further elucidate the pathophysiology of pituitary autoimmunity.

[Pituitary immune-related adverse events induced by programmed cell death protein 1 inhibitors in advanced lung cancer patients: A report of 3 cases]

Pituitary immune-related adverse events induced by programmed cell death protein 1 inhibitors in advanced lung cancer patients: A report of 3 cases SUMMARY Programmed cell death protein 1 (PD-1) and its ligand 1 (PD-L1) have been widely used in lung cancer treatment, but their immune-related adverse events (irAEs) require intensive attention. Pituitary irAEs, including hypophysitis and hypopituitarism, are commonly induced by cytotoxic T lymphocyte antigen 4 inhibitors, but rarely by PD-1/PD-L1 inhibitors. Isolated adrenocorticotropic hormone(ACTH) deficiency (IAD) is a special subtype of pituitary irAEs, without any other pituitary hormone dysfunction, and with no enlargement of pituitary gland, either. Here, we described three patients with advanced lung cancer who developed IAD and other irAEs, after PD-1 inhibitor treatment. Case 1 was a 68-year-old male diagnosed with metastatic lung adenocarcinoma with high expression of PD-L1. He was treated with pembrolizumab monotherapy, and developed immune-related hepatitis, which was cured by high-dose methylprednisolone [0.5-1.0 mg/(kg·d)]. Eleven months later, the patient was diagnosed with primary gastric adenocarcinoma, and was treated with apatinib, in addition to pembrolizumab. After 17 doses of pembrolizumab, he developed severe nausea and asthenia, when methylprednisolone had been stopped for 10 months. His blood tests showed severe hyponatremia (121 mmol/L, reference 137-147 mmol/L, the same below), low levels of 8:00 a.m. cortisol (< 1 μg/dL, reference 5-25 μg/dL, the same below) and ACTH (2.2 ng/L, reference 7.2-63.3 ng/L, the same below), and normal thyroid function, sex hormone and prolactin. Meanwhile, both his lung cancer and gastric cancer remained under good control. Case 2 was a 66-year-old male with metastatic lung adenocarcinoma, who was treated with a new PD-1 inhibitor, HX008, combined with chemotherapy (clinical trial number: CTR20202387). After 5 months of treatment (7 doses in total), his cancer exhibited partial response, but his nausea and vomiting suddenly exacerbated, with mild dyspnea and weakness in his lower limbs. His blood tests showed mild hyponatremia (135 mmol/L), low levels of 8:00 a.m. cortisol (4.3 μg/dL) and ACTH (1.5 ng/L), and normal thyroid function. His thoracic computed tomography revealed moderate immune-related pneumonitis simultaneously. Case 3 was a 63-year-old male with locally advanced squamous cell carcinoma. He was treated with first-line sintilimab combined with chemotherapy, which resulted in partial response, with mild immune-related rash. His cancer progressed after 5 cycles of treatment, and sintilimab was discontinued. Six months later, he developed asymptomatic hypoadrenocorticism, with low level of cortisol (1.5 μg/dL) at 8:00 a.m. and unresponsive ACTH (8.0 ng/L). After being rechallenged with another PD-1 inhibitor, teslelizumab, combined with chemotherapy, he had pulmonary infection, persistent low-grade fever, moderate asthenia, and severe hyponatremia (116 mmol/L). Meanwhile, his blood levels of 8:00 a.m. cortisol and ACTH were 3.1 μg/dL and 7.2 ng/L, respectively, with normal thyroid function, sex hormone and prolactin. All of the three patients had no headache or visual disturbance. Their pituitary magnetic resonance image showed no pituitary enlargement or stalk thickening, and no dynamic changes. They were all on hormone replacement therapy (HRT) with prednisone (2.5-5.0 mg/d), and resumed the PD-1 inhibitor treatment when symptoms relieved. In particular, Case 2 started with high-dose prednisone [1 mg/(kg·d)] because of simultaneous immune-related pneumonitis, and then tapered it to the HRT dose. His cortisol and ACTH levels returned to and stayed normal. However, the other two patients' hypopituitarism did not recover. In summary, these cases demonstrated that the pituitary irAEs induced by PD-1 inhibitors could present as IAD, with a large time span of onset, non-specific clinical presentation, and different recovery patterns. Clinicians should monitor patients' pituitary hormone regularly, during and at least 6 months after PD-1 inhibitor treatment, especially in patients with good oncological response to the treatment.

Immune Checkpoint Inhibitor-Induced Hypophysitis and Patterns of Loss of Pituitary Function

Background

Immune checkpoint inhibitors (ICI) are clinically active across multiple tumor types but the associated immune-related adverse events (irAEs) lead to treatment delays or discontinuation and negatively impact quality-of-life. Hypophysitis is often a permanent irAE that may affect multiple pituitary hormonal axes. Here we comprehensively characterize our institution's clinical experience with ICI-induced hypophysitis and the associated patterns of pituitary function loss.

Methods

Patients with solid tumors, mostly melanoma and renal cell carcinoma (RCC), treated with ICI at Yale Cancer Center were prospectively enrolled from October 2016-May 2021. Demographics and clinical data were obtained from the medical record including type and timing of irAEs. Patients were included in this cohort if hypophysitis was diagnosed by pre-specified biochemical and clinical parameters.

Results

The overall incidence of hypophysitis was 69/490 (14%) in patients with melanoma (n=58, 84%), RCC (n=10,14%), and merkel cell carcinoma (n=1, 1%) who received ipilimumab plus nivolumab (77%; 53/69), anti-PD-(L)1 (17%; 12/69), or ipilimumab monotherapy (6%; 4/69). Of the 69 patients analyzed, median time to hypophysitis on combination ICI versus anti-PD-1 was 2.8 vs. 4.1 months. The incidence of hypophysitis in patients with melanoma was 25% (46/187) with ipilimumab plus nivolumab and 5% (7/129) with anti-PD-(L)1 compared to 9% (7/77) and 8% (3/37), respectively, in patients with RCC. Patients who developed hypophysitis on combination ICI had a higher rate of headache (p=0.05) and co-occurring irAEs (p=0.01) compared anti-PD-(L1)1 monotherapy. At a median follow-up of 2.2 years, 77% of patients were alive. Objective response rates to ICI in melanoma patients were higher than previously reported for unselected populations. Central hypothyroidism and hypogonadism were the most common pituitary axes affected after the adrenal axis. In select cases, there was evidence of spontaneous rebound in free testosterone levels after an initial decline.

Conclusions

We demonstrate a higher rate of ICI-induced hypophysitis than previously reported, which may be reflective of real-world practice due to increased awareness as experience with ICI has grown. In select cases, there was evidence of rebound in free testosterone and/or gonadotropins but not in adrenal axis hormones.

Risk assessment, diagnosis, and treatment of cancer treatment-related adrenal insufficiency

INTRODUCTION

Adrenal insufficiency (AI) is an easily treatable, potentially life-threatening condition, which is increasingly recognized in malignancy. The recent introduction of immune checkpoint inhibitors, in particular, and increasing use of tyrosine kinase inhibitors have increased the frequency of AI in patients with malignancy. A review is therefore warranted to summarize current knowledge on the topic and guide safe clinical practices.

AREAS COVERED

Malignancy may directly impact the hypothalamic-pituitary-adrenal axis and cause AI, or their treatment including surgery, radiotherapy and medication. In this narrative review, we discuss new causes of AI, recognition of suggestive clinical features, diagnosis and subsequent treatment, aiming to avoid potentially fatal adrenal crisis (AC). Standard literature searching and authors assessment of clinical applicability were used.

EXPERT OPINION

Adrenal insufficiency can be easily treated once identified but life threatening if unrecognized. While use of new agents such as immune checkpoint inhibitors (ICIs) is increasing, greater understanding of the mechanism of AI is needed to target prediction tools and enhance risk stratification.

Immune checkpoint inhibitor-induced hypophysitis: lessons learnt from a large cancer cohort

Immune checkpoint inhibitors (ICIs) can cause pituitary dysfunction due to hypophysitis. We aimed to characterize ICI-induced hypophysitis and examine its association with overall survival in this single-center retrospective cohort study of adult patients with cancer who received an ICI from January 1, 2012 through December 31, 2016. A total of 896 patients were identified who received ipilimumab alone (n=120); ipilimumab and nivolumab (n=50); ipilimumab before or after pembrolizumab (n=70); pembrolizumab alone (n=406); and nivolumab alone (n=250). Twenty-six patients (2.9%) developed hypophysitis after a median of 2.3 months. Median age at the start of ICI was 57.9 years and 54% were men. Hypophysitis occurred in 7.9% of patients receiving ipilimumab alone or in combination or sequence with a programmed cell death protein 1 inhibitor; 1.7% after pembrolizumab alone, never after nivolumab alone. Secondary adrenal insufficiency occurred in all hypophysitis cases. Use of ipilimumab alone or in combination was associated with pituitary enlargement on imaging and mass effects more frequently than pembrolizumab alone. Occurrence of hypophysitis was associated with improved overall survival by univariate analysis (median 50.7 vs 16.5 months; p=0.015) but this association was not observed in multivariable landmark survival analysis (HR for mortality 0.75; 95% CI 0.38 to 1.30; p=0.34) after adjusting for age, sex and malignancy type. To conclude, hypophysitis occurred most frequently after ipilimumab and manifested as anterior hypopituitarism affecting the corticotrophs more commonly than thyrotrophs and gonadotrophs. Mass effects and pituitary enlargement occurred more frequently in ipilimumab-induced hypophysitis. The association of hypophysitis with overall survival needs further investigation.

Survival benefit of endocrine dysfunction following immune checkpoint inhibitors for nonthyroidal cancers

PURPOSE OF REVIEW

Our goal is to review pertinent data evaluating the association between immune checkpoint inhibitor (ICI)-induced endocrine dysfunction and survival in cancer patients as well as to understand the potential molecular links between these.

RECENT FINDINGS

ICIs have revolutionized cancer therapy but have also led to multiple immune-related adverse events (irAEs). Studies have demonstrated a link between the development of irAEs and improved survival, suggesting that ICI-induced antitumor immunity and autoimmunity are coupled. Thyroid irAEs are most frequently and strongly associated with improved survival, particularly in the context of overt thyroid dysfunction. Other endocrine irAEs, such as hypophysitis and diabetes are quite rare wherein the treatment approach or the disease process itself may mitigate improvement in survival. Preclinical and translational data indicate a role for CD4+ T cells, regulatory T cells and/or cytokines mediating irAEs, including thyroiditis.

SUMMARY

The development of irAEs is associated with improved tumor responses and survival in cancer patients. Thyroid irAEs, alone or in combination with other irAEs, are most strongly associated with improved outcomes. Biomarkers of response to ICIs are lacking, despite well-characterized pathologic and genomic susceptibilities predicting ICI efficacy. Early detection of thyroid irAEs may identify patients most likely to have durable antitumor response to ICIs. Although irAEs and antitumor immunity appear 'coupled', translational studies indicate the potential for their 'uncoupling', which could enable antitumor efficacy with greater safety margins.

Nivolumab induced hypophysitis in a patient with recurrent non-small cell lung cancer

Nivolumab is a programmed death receptor-1 blocking monoclonal antibody which has been approved by United States Food and Drug Administration for patients with metastatic non-squamous non-small cell lung cancer. Endocrinopathies like thyroid dysfunction and adrenal insufficiency are its known immune related adverse effects. Hypophysitis is very rare and usually presents with minimal symptoms. We report development of hypophysitis in an 84-year-old female patient who developed a range of symptoms (fatigue, headache, nausea) as well as laboratory confirmation of both central hypothyroidism and central adrenal deficiency which is unusual in cases of nivolumab induced hypophysitis. The patient had well differentiated adenocarcinoma of the left upper lobe of the lung. She underwent wedge resection followed by chemotherapy and was started on nivolumab due to recurrence. After 14 cycles of nivolumab, she started complaining of intense fatigue. She was found to have central thyroid deficiency and was started on levothyroxine. But her symptoms did not improve. Then she underwent adrenocorticotropic hormone stimulation test which showed central adrenal deficiency, but her brain magnetic resonance imaging did not reveal any pituitary or sellar changes. A diagnosis of nivolumab induced hypophysitis was made, based on clinical grounds and hormonal profile and she was started on oral steroids. She responded dramatically to this steroidal therapy within four weeks of its initiation and her immunotherapy with nivolumab was restarted.