Ipilimumab-induced hypophysitis in melanoma patients: an Australian case series

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.

AMERICAN ASSOCIATION OF CLINICAL ENDOCRINOLOGY (AACE) DISEASE STATE CLINICAL REVIEW EVALUATION AND MANAGEMENT OF IMMUNE CHECKPOINT INHIBITOR-MEDIATED ENDOCRINOPATHIES: A PRACTICAL CASE-BASED CLINICAL APPROACH

OBJECTIVE

The aim of this case-based clinical review is to provide a practical approach for clinicians regarding the management of patients with immune checkpoint inhibitor (ICI)-mediated endocrinopathies.

METHODS

A literature search was conducted using PubMed, Embase and Scopus, and appropriate keywords. The discussions and strategies for diagnosis and management of ICI-mediated endocrinopathies are based on evidence available from prospective randomized clinical studies, cohort studies, cross-sectional studies, case-based studies, and expert consensus.

RESULTS

Immunotherapy with ICIs has transformed the treatment landscape of diverse cancer types, but frequently results in immune-mediated endocrinopathies that can cause acute and persistent morbidity, and rarely, death. The patterns of endocrinopathies differ between inhibitors of the CTLA-4 and PD-1/PD-L1 pathways, but most often involve the thyroid and pituitary glands. Less common but important presentations include insulin-deficient diabetes mellitus, primary adrenal insufficiency, primary hypoparathyroidism, central diabetes insipidus, primary hypogonadism, and pancreatitis with or without subsequent progression to diabetes or exocrine insufficiency.

CONCLUSION

In recent years, with increasing numbers of cancer patients being treated with ICIs, more clinicians in a variety of specialties are called upon to diagnose and treat ICI-mediated endocrinopathies. Herein, we review case scenarios of various clinical manifestations, and emphasize the need for a high index of clinical suspicion by all clinicians caring for these patients including endocrinologists, oncologists, primary care providers, and emergency department physicians. We also provide diagnostic and therapeutic approaches for ICI-induced endocrinopathies, and we propose that patients on ICI-therapy be evaluated and treated in a multidisciplinary team in collaboration with endocrinologists.

The changing clinical spectrum of endocrine adverse events in cancer immunotherapy

Immune checkpoint inhibitors (ICIs) have revolutionized the treatment of several malignancies, improving patient survival and quality of life. Endocrinopathies have emerged as a clinically significant group of immune-related adverse events (IRAEs). Although the mechanism of ICI toxicities has not been clarified, inhibition of immune checkpoints reduces immune tolerance to autoantigens, resulting in the development of autoimmunity disorders. We report current evidence regarding endocrine IRAEs that may have diagnostic and therapeutic implications. Management should be focused on a multidisciplinary approach to reach a prompt diagnosis and an appropriate and safe treatment.

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.

Immune checkpoint inhibitor related hypophysitis: diagnostic criteria and recovery patterns

Data on the diagnosis, natural course and management of immune checkpoint inhibitor (ICI)-related hypophysitis (irH) are limited. We propose this study to validate the diagnostic criteria, describe characteristics and hormonal recovery and investigate factors associated with the occurrence and recovery of irH. A retrospective study including patients with suspected irH at the University of Texas MD Anderson Cancer Center from 5/2003 to 8/2017 was conducted. IrH was defined as: (1) ACTH or TSH deficiency plus MRI changes or (2) ACTH and TSH deficiencies plus headache/fatigue in the absence of MRI findings. We found that of 83 patients followed for a median of 1.75 years (range 0.6-3), the proposed criteria used at initial evaluation accurately identified 61/62 (98%) irH cases. In the irH group (n = 62), the most common presentation was headache (60%), fatigue (66%), central hypothyroidism (94%), central adrenal insufficiency (69%) and MRI changes (77%). Compared with non-ipilimumab (ipi) regimens, ipi has a stronger association with irH occurrence (P = 0.004) and a shorter time to irH development (P < 0.01). Thyroid, gonadal and adrenal axis recovery occurred in 24, 58 and 0% patients, respectively. High-dose steroids (HDS) or ICI discontinuation was not associated with hormonal recovery. In the non-irH group (n = 19), one patient had isolated central hypothyroidism and six had isolated central adrenal insufficiency. All remained on hormone therapy at the last follow-up. We propose a strict definition of irH that identifies the vast majority of patients. HDS and ICI discontinuation is not always beneficial. Long-term follow-up to assess recovery is needed.

The hypothalamus-pituitary-thyroid (HPT)-axis and its role in physiology and pathophysiology of other hypothalamus-pituitary functions

The hypothalamus-pituitary-thyroid axis is one of several hormone regulatory systems from the hypothalamus to the pituitary and ultimately to the peripheral target organs. The hypothalamus and the pituitary gland are in close anatomical proximity at the base of the brain and extended through the pituitary stalk to the sella turcica. The pituitary stalk allows passage of stimulatory and inhibitory hormones and other signal molecules. The target organs are placed in the periphery and function through stimulation/inhibition by the circulating pituitary hormones. The several hypothalamus-pituitary-target organ axis systems interact in very sophisticated and complicated ways and for many of them the interactive and integrated mechanisms are still not quite clear. The diagnosis of central hypothyroidism is complicated by itself but challenged further by concomitant affection of other hypothalamus-pituitary-hormone axes, the dysfunction of which influences the diagnosis of central hypothyroidism. Treatment of both the central hypothyroidism and the other hypothalamus-pituitary axes also influence the function of the others by complex mechanisms involving both central and peripheral mechanisms. Clinicians managing patients with neuroendocrine disorders should become aware of the strong integrative influence from each hypothalamus-pituitary-hormone axis on the physiology and pathophysiology of central hypothyroidism. As an aid in this direction the present review summarizes and highlights the importance of the hypothalamus-pituitary-thyroid axis, pitfalls in diagnosing central hypothyroidism, diagnosing/testing central hypothyroidism in relation to panhypopituitarism, pointing at interactions of the thyroid function with other pituitary hormones, as well as local hypothalamic neurotransmitters and gut-brain hormones. Furthermore, the treatment effect of each axis on the regulation of the others is described. Finally, these complicating aspects require stringent diagnostic testing, particularly in clinical settings with lower or at least altered à priori likelihood of hypopituitarism than in former obvious clinical patient presentations.

The side effects of immune checkpoint inhibitor therapy on the endocrine system

Immune checkpoint inhibitors (ICIs) are a relatively newer class of drugs approved for the treatment of malignancies such as melanoma, renal, bladder and lung cancer. Immune-related adverse events (IrAEs) involving the endocrine system are a common side effect of these drugs. The spectrum of endocrine adverse events varies by the drug class. Cytotoxic T-lymphocyte–associated antigen-4 inhibitors commonly cause hypophysitis/hypopituitarism, whereas the incidence of thyroid disease is higher with programmed cell death (PD)-1/ ligand (PD-L) protein 1 inhibitors. The focus of this review is to describe the individual endocrinopathies with their possible mechanisms, signs and symptoms, clinical assessment and disease management. Multiple mechanisms of IrAEs have been described in literature including type II/IV hypersensitivity reactions and development of autoantibodies. Patients with pre-existing autoimmune endocrine diseases can have disease exacerbation following ICI therapy rather than de novo IrAEs. Most of the endocrinopathies are relatively mild, and timely hormone replacement therapy allows continuation of ICIs. However, involvement of the pituitary–adrenal axis could be life-threatening if not recognized. Corticosteroids are helpful when the pituitary–adrenal axis is involved. In cases of severe endocrine toxicity (grade 3/4), ICIs should be temporarily discontinued and can be restarted after adequate hormonal therapy. Endocrinologists and general internists need to be vigilant and maintain a high degree of awareness for these adverse events.

Pituitary enlargement following ipilimumab without long term endocrine dysfunction

Ipilimumab, a monoclonal antibody against CTLA-4, is used in the treatment of melanoma and renal cell cancer. Hypophysitis is one of the more common adverse events, usually presenting with headache, pituitary enlargement and hypopituitarism, mostly ACTH deficiency, which is usually permanent. We describe a series of 3 cases developing pituitary enlargement in keeping with hypophysitis after ipilimumab without any long-term pituitary hormone deficiencies. This illustrates that a comprehensive endocrine assessment is required even when pituitary enlargement is present.

Primary and Ipilimumab-induced Hypophysitis: A Single-center Case Series

PURPOSE

To present a case series of primary and immunotherapy-related secondary hypophysitis.

METHODS

A single-center retrospective chart review was performed at the University of British Columbia, Vancouver, Canada. Eleven cases of primary hypophysitis and 2 cases of immunotherapy-related secondary hypophysitis were included. Of the 11 primary cases, 6 were diagnosed clinically without biopsy.

RESULTS

In primary hypophysitis, headache was the most common presenting symptom (6/11; 55%) and stalk enlargement the prevailing radiologic sign (8/11; 73%). Central adrenal insufficiency (4/11; 36%), central hypothyroidism (4/11; 36%), and central diabetes insipidus (CDI) (4/11; 36%) were the most common pituitary deficiencies at presentation. Initial management included surgery (4/11; 36%), supraphysiologic steroids (2/11; 18%), or observation (6/11; 55%). Outcomes assessed included radiologic improvement (8/9; 89%), improvement in mass symptoms (4/7; 57%), anterior pituitary recovery (1/7; 14%), and CDI recovery (0/4; 0%). In immunotherapy-related hypophysitis either under observation or supraphysiologic steroid therapy, the inflammatory mass resolved and pituitary dysfunction persisted.

CONCLUSIONS

In primary hypophysitis, the inflammatory pituitary mass typically resolves and hypopituitarism persists. In the absence of severe or progressive neurologic deficits, a presumptive clinical diagnosis and conservative medical management should be attempted. In the absence of severe features, immunotherapy-related hypophysitis may be managed effectively without the use of supraphysiologic steroids.

Autoimmune hypophysitis secondary to therapy with immune checkpoint inhibitors: Four cases describing the clinical heterogeneity of central endocrine dysfunction

INTRODUCTION

Immune checkpoint inhibitors are becoming increasingly important in oncology. Immune-related adverse events, including autoimmune hypophysitis, have been reported before.

CASE REPORT

We present a case series of three males and one female, suffering from either malignant melanoma or renal cell carcinoma, who developed hypophysitis under Nivolumab and/or Ipilimumab. A wide range of clinical manifestations from asymptomatic hypophysitis, headache, general weakness, loss of appetite, visual field impairment, and confusion to acute life-threatening Addison crisis was observed.Management and outcome: All patients received corticosteroids. Immune checkpoint inhibitors were discontinued in three cases until resolution of symptoms.

DISCUSSION

The objective of our report is to raise the awareness of physicians, regarding this rare clinical entity, which may become life-threatening, if not promptly recognized and properly treated.

Immunotherapy-induced endocrinopathies: assessment, management and monitoring

Immunotherapy with checkpoint inhibitors has transformed the treatment of cancer, but frequently results in immune-mediated adverse events affecting multiple organs, amongst which endocrine adverse events are frequent. The patterns of endocrine adverse events differ between inhibitors of the CTLA-4 and PD-1/PD-L1 pathways, but most frequently involve the thyroid and pituitary with insulin deficient diabetes also emerging as an important adverse event. These frequently result in long-lasting hormone deficiency requiring replacement. This review explores the mechanism of action of checkpoint inhibitors and details the expected endocrine adverse events and typical presentations. The effect of high-dose glucocorticoids therapy to treat nonendocrine adverse events is also discussed.

Cancer immunotherapy-associated hypophysitis

The advances in cancer therapy have included the development of drugs that inhibit immune checkpoint ligands. Two types of immune checkpoint inhibitors, both antibodies that target CTLA-4 and PD-1, have been approved for its use in NSCLC and melanoma as first-line or second-line therapy. Sadly, not desirable consequences of immunotherapy are immune-related adverse events. immune-related hypophysitis is the most common endocrine adverse event after thyroid disfunction. The particularity of endocrine immune-related adverse events is their non-reversibility, with incidence and prevalence destined to increase in the coming years, particularly if this form of therapy is used in the future for earlier stages of cancer. Therefore, hypophysitis represents a challenge for the physician, sometimes occurring without specific symptomatology and which should be considered for clinical management. In this review, we describe the current data regarding the pathophysiology and management for immune-related hypophysitis.

Hypophysitis in the era of immune checkpoint inhibitors and immunoglobulin G4-related disease

INTRODUCTION

Hypophysitis is a rare disorder, defined as inflammation of the pituitary gland that may result in pituitary enlargement and varying anterior and posterior pituitary hormonal deficits. It involves different histopathological subtypes and variable etiologies, with considerable overlap between classification systems. Histopathology is the gold standard diagnostic approach.

AREAS COVERED

In this article, we will review the major histopathological subtypes of hypophysitis with a special focus on immunoglobulin G4 (IgG4)-related hypophysitis and immune checkpoint inhibitor-induced hypophysitis, given their recent appearance and increasing incidence. We will summarize the similarities and differences between the different subtypes as it relates to epidemiology, pathogenesis, presentation, diagnosis, and management.

EXPERT OPINION

Hypophysitis is a heterogeneous and wide term used to describe different, possibly distinct diseases often with poorly understood pathogenesis. It involves a wide range of subtypes with certain differences in incidence rates, pathogenesis, and management. Management usually focuses on relieving the mass effect symptoms and replacing the deficient pituitary hormones. Spontaneous recovery is possible but recurrence is not uncommon.

Spectrum of immune checkpoint inhibitors-induced endocrinopathies in cancer patients: a scoping review of case reports

BACKGROUND

Since 2011 six immune checkpoint inhibitors (ICI) have been approved to treat patients with many advanced solid tumor and hematological malignancies to improve their prognosis. Case reports of their endocrine immune-related adverse events [irAEs]) are increasingly published as more real-world patients with these malignancies are treated with these drugs. They alert physicians of a drug's AEs (which may change during a drug's life cycle) and contribute to post-marketing safety surveillance. Using a modified framework of Arksey and O'Malley, we conducted a scoping review of the spectrum and characteristics of ICI-induced endocrinopathies case reports before and after ICIs are marketed.

METHODS

In July 2017, we searched, without date and language restrictions, 4 citation databases for ICI-induced endocrinopathies. We also hand-searched articles' references, contents of relevant journals, and ran supplemental searches to capture recent reports through January 2018. For this study, a case should have information on type of cancer, type of ICI, clinical presentation, biochemical tests, treatment plus temporal association of ICI initiation with endocrinopathies. Two endocrinologists independently extracted the data which were then summarized and categorized.

RESULTS

One hundred seventy nine articles reported 451 cases of ICI-induced endocrinopathies - 222 hypopituitarism, 152 thyroid disorders, 66 diabetes mellitus, 6 primary adrenal insufficiencies, 1 ACTH-dependent Cushing's syndrome, 1 hypoparathyroidism and 3 diabetes insipidus cases. Their clinical presentations reflect hormone excess or deficiency. Some were asymptomatic and others life-threatening. One or more endocrine glands could be affected. Polyglandular endocrinopathies could present simultaneously or in sequence. Many occur within 5 months of therapy initiation; a few occurred after ICI was stopped. Mostly irreversible, they required long-term hormone replacement. High dose steroids were used when non-endocrine AEs coexisted or as therapy in adrenal insufficiency. There was variability of information in the case reports but all met the study criteria to make a diagnosis.

CONCLUSIONS

The spectrum of ICI-induced endocrinopathies is wide (5 glands affected) and their presentation varied (12 endocrinopathies). Clinical reasoning integrating clinical, biochemical and treatment information is needed to properly diagnose and manage them. Physicians should be vigilant for their occurrence and be able to diagnose, investigate and manage them appropriately at onset and follow-up.

Fall in thyroid stimulating hormone (TSH) may be an early marker of ipilimumab-induced hypophysitis

PURPOSE

Hypophysitis develops in up to 19% of melanoma patients treated with ipilimumab, a cytotoxic T-lymphocyte antigen-4 antibody. Early detection may avert life-threatening hypopituitarism. We aimed to assess the incidence of ipilimumab-induced hypophysitis (IH) at a quaternary melanoma referral centre, and to determine whether cortisol or thyroid stimulating hormone (TSH) monitoring could predict IH onset.

METHODS

We performed a retrospective cohort study of ipilimumab-treated patients at a quaternary melanoma referral centre in Australia. The inclusion criteria were patients with metastatic or unresectable melanoma treated with ipilimumab monotherapy, and cortisol and TSH measurements prior to ≥ 2 infusions. The main outcomes were IH incidence and TSH and cortisol patterns in patients who did and did not develop IH.

RESULTS

Of 78 ipilimumab-treated patients, 46 met the study criteria and 9/46 (20%) developed IH at a median duration of 13.0 weeks (range 7.7-18.1) following ipilimumab initiation. All patients whose TSH fell ≥ 80% compared to baseline developed IH, and, in 5/9 patients with IH, TSH fell prior to cortisol fall and IH diagnosis. Pre-cycle-4 TSH was significantly lower in those who developed IH (0.31 vs. 1.73 mIU/L, P = 0.006). TSH fall was detected at a median time of 9.2 (range 7.7-16.4) weeks after commencing ipilimumab, and a median of 3.6 (range of - 1.4 to 9.7) weeks before IH diagnosis. There was no difference in TSH between the groups before cycles 1-3 or in cortisol before cycles 1-4.

CONCLUSIONS

TSH fall ≥ 80% may be an early marker of IH. Serial TSH measurement during ipilimumab therapy may be an inexpensive tool to expedite IH diagnosis.

Central hypothyroidism - a neglected thyroid disorder

Central hypothyroidism is a rare and heterogeneous disorder that is characterized by a defect in thyroid hormone secretion in an otherwise normal thyroid gland due to insufficient stimulation by TSH. The disease results from the abnormal function of the pituitary gland, the hypothalamus, or both. Moreover, central hypothyroidism can be isolated or combined with other pituitary hormone deficiencies, which are mostly acquired and are rarely congenital. The clinical manifestations of central hypothyroidism are usually milder than those observed in primary hypothyroidism. Obtaining a positive diagnosis for central hypothyroidism can be difficult from both a clinical and a biochemical perspective. The diagnosis of central hypothyroidism is based on low circulating levels of free T₄ in the presence of low to normal TSH concentrations. The correct diagnosis of both acquired (also termed sporadic) and congenital (also termed genetic) central hypothyroidism can be hindered by methodological interference in free T₄ or TSH measurements; routine utilization of total T₄ or T₃ measurements; concurrent systemic illness that is characterized by low levels of free T₄ and normal TSH concentrations; the use of the sole TSH-reflex strategy, which is the measurement of the sole level of TSH, without free T₄, if levels of TSH are in the normal range; and the diagnosis of congenital hypothyroidism based on TSH analysis without the concomitant measurement of serum levels of T₄. In this Review, we discuss current knowledge of the causes of central hypothyroidism, emphasizing possible pitfalls in the diagnosis and treatment of this disorder.

Glucocorticoids did not reverse type 1 diabetes mellitus secondary to pembrolizumab in a patient with metastatic melanoma

Immune checkpoint inhibitors offer patients with advanced melanoma substantial improvements in survival. Unlike chemotherapy, immune checkpoint inhibitors such as ipilimumab and pembrolizumab cause unique immune-related adverse events (irAEs), including the development of endocrinopathies. We report a case of a man aged 60 years who developed diabetic ketoacidosis (DKA) following the use of pembrolizumab for the treatment of metastatic melanoma. He received four cycles of ipilimumab, before proceeding to pembrolizumab. Five weeks after initiating pembrolizumab, he presented in DKA with a pH of 7.0, bicarbonate of 7 mmol/L, blood glucose of 27 mmol/L and serum ketones of 5.9 mmol/L. Antibodies to glutamic acid decarboxylase (anti-GAD) and Islet antigen 2 (IA-2) were negative and C-peptide was low at 57 pmol/L (300-2350 pmol/L). There was no personal or family history of autoimmune conditions. Standard immunosuppression for irAEs was started using prednisolone in an attempt to salvage β cell function but was unsuccessful. To the best of our knowledge, this is the first reported attempt at reversing pembrolizumab-induced type 1 diabetes using glucocorticoids.