Hypophysitis induced by monoclonal antibodies to cytotoxic T lymphocyte antigen 4: challenges from a new cause of a rare disease

Drawbacks of immune checkpoint inhibition and rigorous management for immune-related adverse events along with a mathematical model to assess therapy success and optimum therapy duration and a strategy against tumor plasticity

PURPOSE

Immune checkpoint inhibition therapy (ICIT) is an emerging field in oncology especially opening new horizons to chemotherapy refractory patients. However, immune-related adverse events (irAEs) and undesired response patterns such as progression after the initial good response in a subset of patients pose a major challenge and drawback to ICIT. This paper provides deep insight into ICIT related bottlenecks and corresponding effective management and combat strategies for very complex complications.

METHODS

The relevant literatures from PubMed have been reviewed. Based on obtained information, rigorous and exhaustive analyses have been made to present novel methods and strategies against ICIT drawbacks and bottlenecks.

RESULTS

The results show that baseline biomarker tests are very crucial to identify suitable candidates for ICIT and frequent assessments throughout ICIT help to recognize possible irAEs at early stages. Equally important are the necessity for mathematical definitions for the ICIT success rate and optimum duration, and the development of combat mechanisms against loss of sensitivity within the tumor microenvironment (TME).

CONCLUSION

Rigorous management approaches are presented for mostly observed irAEs. Furthermore, for the first time in the literature, a non-linear mathematical model is invented to measure the ICIT success rate and to decide about the optimum ICIT duration. Finally, a strategy against tumor plasticity is introduced.

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.

Immunopathological basis of immune-related adverse events induced by immune checkpoint blockade therapy

Despite the considerable success of cancer immunotherapy with immune checkpoint inhibitors, their nonspecific release of the immunosuppressive mechanism is often associated with immune-related adverse events (irAEs). irAEs significantly disturb patients' quality of life and can even be life-threatening. Therefore, the appropriate management of irAEs is crucial for the development of further reliable cancer immunotherapies. irAEs have the appearance of ordinary autoimmune diseases in one aspect but often have distinct features. Although the detailed pathogenesis of irAEs remains unclear, increasing numbers of studies have provided numerous clues. Here, we review the current knowledge on irAEs, particularly from an immunopathological basis.

Hypophysitis related to immune checkpoint inhibitors: An intriguing adverse event with many faces

INTRODUCTION

The incorporation of immune checkpoint inhibitors in the oncologists' arsenal is a milestone in cancer therapeutics, though not being devoid of toxicities.Areas covered: The present review provides a comprehensive and up-to-date overview of the immune-related hypophysitis with focus on the elusive biological background, the wide spectrum of the epidemiological profile, the varying clinical aspects, and the diagnostic and therapeutic challenges.Expert opinion: Historically considered distinctive of anti-cytotoxic T-lymphocyte antigen 4 (CTLA-4) monoclonal antibodies (mAbs), the immune-related hypophysitis is increasingly correlated with the anti-programmed cell-death (PD) protein 1 (PD-1)/anti-PD ligand 1 (PD-L1) mAbs. The distinct phenotype of hypophysitis related to anti-PD1/anti-PD-L1 mAbs is highlighted with focus on the immune-related isolated adrenocorticotropic (ACTH) deficiency. The immune-related central diabetes insipidus is discussed as a rare aspect of anti-CTL-A4 mAbs-induced hypophysitis, recently related to anti-PD1/anti-PD-L1 mAbs as well. The present review builds on existing literature concerning immune-related hypophysitis underscoring the pending issues still to be addressed, including (i) pathogenesis; (ii) correlation with preexisting autoimmunity; (iii) predictive value; (iv) utility of high-dose glucocorticoids; and (v) establishment of evidence-based diagnostic and therapeutic protocols. Increased awareness and constant vigilance are advocated as cornerstone of a multidisciplinary approach to ensure optimal patients' care.

Endocrine toxicity of cancer immunotherapy: clinical challenges

Immune checkpoint inhibitors are now widely used in the treatment of multiple cancers. The major toxicities of these treatments are termed immune-related adverse events and endocrine dysfunction is common. Thyroid disease, hypopituitarism and a form of diabetes resembling type 1 diabetes are now all well described, with different patterns emerging with different checkpoint inhibitors. We review the presentation and management of the common endocrine immune-related adverse events, and discuss a number of recent advances in the understanding of these important, potentially life threatening toxicities. We also discuss some remaining dilemmas in management.

How we treat endocrine complications of immune checkpoint inhibitors

Immune checkpoint inhibitors (ICIs) are antibodies that target certain immune checkpoints (ICs), such as cytotoxic T-lymphocyte-associated protein 4 (CTLA-4), programmed death 1 (PD-1) or its ligand (PD-L1), and have emerged as a powerful new tool for oncologists. As these immune checkpoints are crucial for immunological self-tolerance, such therapies can trigger autoimmune adverse effects. Endocrine complications are among the most common, including hypophysitis, thyroid dysfunction, diabetes mellitus and primary adrenal insufficiency, while autoimmune polyendocrine syndrome type 2 (APS-2) may also present. The aim of this article is to critically appraise the literature and present (i) the biological role and function of the main ICs, (ii) the use of ICIs in the treatment of various cancer types, (iii) the endocrine complications of cancer immunotherapy with ICIs and (iv) practical recommendations for screening and management of patients with such endocrinopathies in everyday clinical practice.

Predicting development of ipilimumab-induced hypophysitis: utility of T4 and TSH index but not TSH

PURPOSE

Ipilimumab, a monoclonal antibody inhibiting CLTA-4, is an established treatment in metastatic melanoma, either alone or in combination with nivolumab, and results in immune mediated adverse events, including endocrinopathy. Hypophysitis is one of the most common endocrine abnormalities. An early recognition of hypophysitis may prevent life threatening consequences of hypopituitarism; therefore, biomarkers to predict which patients will develop hypophysitis would have clinical utility. Recent studies suggested that a decline in TSH may serve as an early marker of IH. This study was aimed at assessing the utility of thyroid function tests in predicting development of hypophysitis.

METHODS

A retrospective cohort study was performed for all patients (n = 308) treated with ipilimumab either as a monotherapy or in combination with nivolumab for advanced melanoma at the Royal Marsden Hospital from 2010 to 2016. Thyroid function tests, other pituitary function tests and Pituitary MRIs were used to identify those with hypophysitis.

RESULTS AND CONCLUSIONS

Ipilimumab-induced hypophysitis (IH) was diagnosed in 25 patients (8.15%). A decline in TSH was observed in hypophysitis cohort during the first three cycles but it did not reach statistical significance (P = 0.053). A significant fall in FT4 (P < 0.001), TSH index (P < 0.001) and standardised TSH index (P < 0.001) prior to cycles 3 and 4 in hypophysitis cohort was observed. TSH is not useful in predicting development of IH. FT4, TSH index and standardised TSH index may be valuable but a high index of clinical suspicion remains paramount in early detection of hypophysitis.

Diagnosis and management of immune-related adverse effects of immune checkpoint therapy in the emergency department

Rapid advances in cancer immunotherapy using immune checkpoint inhibitors have led to significantly improved survival. Rapid identification of the toxicity syndromes associated with these therapeutic agents is very important for emergency physicians because the population of patients diagnosed with cancer is increasing and cancer therapies including immune checkpoint inhibitors have become the first-line treatment for more and more types of cancer. The emergency medicine literature lags behind rapid advances in oncology, and oncology guidelines for rapid recognition and management of these emerging toxicity syndromes are not familiar to emergency physicians. In this review article, we discuss the clinical presentation and management of immune-related adverse effects during the critical first hours of emergency care. We also suggest a workflow for the recognition and treatment of emergencies arising from serious immune-related adverse effects, including but not limited to colitis, adrenal crisis, myocarditis, pneumonitis, myasthenic crisis, diabetic ketoacidosis, bullous pemphigus, and hemophagocytic lymphohistiocytosis. Rapid advances in cancer therapy are bringing new diagnostic and therapeutic challenges to emergency providers, and therefore it is crucial to raise awareness and provide guidelines for the management of new treatment-related toxicities.

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.

Management of endocrine immune-related adverse events of immune checkpoint inhibitors: an updated review

Immune checkpoint inhibitors (ICIs) belong to a new group of anticancer drugs targeting T-cell proteins involved in the activation of immune response toward malignancies. Their introduction into clinical practice was a milestone in modern cancer treatment. However, the significant advantage of ICIs over conventional chemotherapy in terms of therapeutic efficacy is accompanied by new challenges related to specific side effects. ICI-induced immune system activation could lead to the loss of self-tolerance, presenting as autoimmune inflammation and dysfunction of various tissues and organs. Thus, the typical side effects of ICIs include immune-related adverse events (irAEs), among which endocrine irAEs, affecting numerous endocrine glands, have been commonly recognized. This review aimed to outline the current knowledge regarding ICI-induced endocrine disorders from a clinical perspective. We present updated information on the incidence and clinical development of ICI-induced endocrinopathies, including the most frequent thyroiditis and hypophysitis, the rarely observed insulin-dependent diabetes mellitus and primary adrenal insufficiency, and the recently described cases of hypoparathyroidism and lipodystrophy. Practical guidelines for monitoring, diagnosis, and treatment of ICI-related endocrine toxicities are also offered. Rising awareness of endocrine irAEs among oncologists, endocrinologists, and other health professionals caring for patients receiving ICIs could contribute to better safety and efficacy. As immunotherapy becomes widespread and approved for new types of malignancies, increased incidences of endocrine irAEs are expected in the future.

A Novel Etiology of Hypophysitis: Immune Checkpoint Inhibitors

Checkpoint inhibitors trigger an immune process against cancer cells while causing cytotoxicity and self-antibody production against normal cells. Hypophysitis is a common endocrine toxicity. Hypophysitis may occur at any time during and after therapy, necessitating close clinical monitoring and screening for pituitary deficiencies. Treatment with high-dose glucocorticoids and temporary cessation of immunotherapy is indicated for severe hypophysitis with intractable headaches and vision changes, and for adrenal crisis. Increased awareness about this novel hypophysitis and multidisciplinary collaboration are needed to improve outcomes. This article reviews the function of immune checkpoint inhibitors and pituitary adverse effects with immune checkpoint inhibitor use.

Immuno-related endocrinopathy in patients treated with immune checkpoint inhibitors

Recently immune checkpoint inhibitors amazingly changed the landscape of cancer therapy worldwide. The number of immune checkpoint molecules in clinical practice is constantly increasing. There are some monoclonal antibodies recently registered in the Russian Federation: anti-PD1 antibodies (nivolumab, pembrolizumab), anti-PD-L1 (atezolizumab, durvalumab), anti-CTLA-4 (ipilimumab). Immune-mediated endocrinopathies are some of the most common complications of immunotherapy. According to the results of clinical studies, the incidence of serious endocrine immuno-mediated adverse events with anti-PD1 monoclonal antibodies is low (3.5–8%). The use of anti-CTLA4 antibodies, combined regimens, and the use of immunotherapy after chemoradiotherapy significantly increase the incidence of serious adverse events to 30%. In clinical practice of N.N. Blokhin Cancer Research Center among 245 non-small cell lung cancer and hepatocellular carcinoma patients treated with immunotherapy, 22 (8,9%) developed an immune-mediated endocrinopathy. Most patients developed adverse events of 1–2 degrees, in two patients – 3 degrees, requiring discontinuation of treatment. The aim of this article was to provide useful information and recommendations regarding the management of common immuno-related endocrine adverse events (including hypothyroidism, hyperthyroidism, pituitary, adrenal insufficiency) for clinical oncologists.

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.

Immunotoxicity from checkpoint inhibitor therapy: clinical features and underlying mechanisms

Immune checkpoint inhibition with monoclonal antibodies is becoming increasingly commonplace in cancer medicine, having contributed to a widening of therapeutic options across oncological indications. Disruption of immune tolerance is the key mechanism of action of checkpoint inhibitors and although immune-related adverse events are a typical class effect of these compounds, the relationship between toxicity and response is not fully understood. Awareness and vigilance are paramount in recognizing potentially life-threatening toxicities and managing them in a timely manner. In this review article, we provide an overview of the clinical features, pathological findings and management principles of common immune-related toxicities, attempting to provide mechanistic insight into an increasingly common complication of cancer therapy.

Ipilimumab-induced hypophysitis, a single academic center experience

BACKGROUND

Immune checkpoint inhibitors, single or in combination, have recently become a cornerstone for the treatment of many malignancies. Ipilimumab, a CTLA-4 inhibitor, was initially FDA approved for treatment of unresectable or metastatic melanoma and subsequently in combination therapy for other cancers. Ipilimumab-induced hypophysitis (IH) risk of development varies in different studies between 0 and 17%. Furthermore, little is known on how to predict which patients will develop IH and its impact on efficacy of Ipilimumab and survival for these patients. Here we reviewed IH and its impact on progression-free survival (PFS) and overall survival (OS).

METHODS

Retrospective, IRB- approved review of consecutive 117 melanoma patients who received ipilimumab between 2011 and 2016 was undertaken. Demographic and clinical characteristics, treatment timing and doses, time to progression after therapy, and survival data were reviewed. Patients were predefined in two groups: patients with and without IH. Descriptive statistics were used to summarize the demographic and clinical characteristics of the study sample. All values are shown as means and standard deviation [mean (SD)] unless indicated otherwise. P < 0.05 was considered to be statistically significant.

RESULTS

Of the 117 patients, 15 (12.8%) with a median age of 62.1 years developed IH. In the IH cohort, 10 (66.7%) were male and were significantly older than females (median 67.7 vs. 50.8; P = 0.009). This difference was not seen in non-IH group. Male patients with IH were significantly older than males without IH (67.7 vs. 56.4 years, P = 0.020), however this difference was not observed in females. No patient who received prior cancer systemic therapy (0/30) developed IH vs. 17.2% (15/72) without prior therapy developed IH (OR 0.00; 95% CI 0.00 to 0.73, P = 0.011). Between IH and non-IH patients, there was no difference in gender, race, ethnicity, BMI, diabetes or autoimmune disease at baseline, number of administered ipilimumab cycles, presence of primary melanoma lesion, or BRAF status. IH and non-IH patients had a similar median PFS (8.1 vs. 6.8 months, HR = 0.51, 95% CI 0.24 to 1.05 P = 0.062) and OS (53.3 vs. 29.5 months; HR 0.66, 95% CI 0.30 to 1.46; P = 0.307).

CONCLUSION

In this study of melanoma patients treated with Ipilimumab, risk of developing IH was high (almost 13%). Older age in men and no prior cancer therapy were associated with IH higher risk. Development of IH was not associated with PFS or OS. Increased use of immune checkpoint inhibitors in the future will impact IH overall risk, thus awareness is needed. Given the lack of reliable identifiable risk factors, close monitoring of signs and symptoms after each therapy cycle is critical for early detection and treatment of hypophysitis.

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.

Immune checkpoint inhibitor therapy for pediatric cancers: A mini review of endocrine adverse events

In recent years, immune checkpoint inhibitor therapy has attracted a great deal of attention in the field of cancer treatment. In the clinical setting, antibodies targeting programmed cell death-1 (PD-1) and cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) have been successfully used to treat adult patients with various types of intractable cancer. However, in a substantial number of patients, ICI therapy is associated with autoimmune toxicities known as immune-related adverse events (IRAEs). Endocrinopathies, such as hypophysitis or autoimmune thyroid disease, may occur and can present unique clinical features that have not been documented with traditional chemotherapies. A Japanese clinical trial evaluating the anti-PD-1 antibody nivolumab for the treatment of pediatric patients with refractory malignant solid tumors and Hodgkin lymphoma has been ongoing since 2017. Moreover, tumors associated with Lynch syndrome, a hereditary form of mismatch repair deficiency, are being focused and represent the next target for ICI therapy in Japan. For the safe management of pediatric cancer patients treated with ICIs, pediatric endocrinologists must be aware of the risk of autoimmune endocrinopathies and perform relevant screening tests at appropriate stages of growth and development.

Endocrine Toxicity of Cancer Immunotherapy Targeting Immune Checkpoints

Immune checkpoints are small molecules expressed by immune cells that play critical roles in maintaining immune homeostasis. Targeting the immune checkpoints cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) and programmed death 1 (PD-1) with inhibitory antibodies has demonstrated effective and durable antitumor activity in subgroups of patients with cancer. The US Food and Drug Administration has approved several immune checkpoint inhibitors (ICPis) for the treatment of a broad spectrum of malignancies. Endocrinopathies have emerged as one of the most common immune-related adverse events (irAEs) of ICPi therapy. Hypophysitis, thyroid dysfunction, insulin-deficient diabetes mellitus, and primary adrenal insufficiency have been reported as irAEs due to ICPi therapy. Hypophysitis is particularly associated with anti-CTLA-4 therapy, whereas thyroid dysfunction is particularly associated with anti-PD-1 therapy. Diabetes mellitus and primary adrenal insufficiency are rare endocrine toxicities associated with ICPi therapy but can be life-threatening if not promptly recognized and treated. Notably, combination anti-CTLA-4 and anti-PD-1 therapy is associated with the highest incidence of ICPi-related endocrinopathies. The precise mechanisms underlying these endocrine irAEs remain to be elucidated. Most ICPi-related endocrinopathies occur within 12 weeks after the initiation of ICPi therapy, but several have been reported to develop several months to years after ICPi initiation. Some ICPi-related endocrinopathies may resolve spontaneously, but others, such as central adrenal insufficiency and primary hypothyroidism, appear to be persistent in most cases. The mainstay of management of ICPi-related endocrinopathies is hormone replacement and symptom control. Further studies are needed to determine (i) whether high-dose corticosteroids in the treatment of ICPi-related endocrinopathies preserves endocrine function (especially in hypophysitis), and (ii) whether the development of ICPi-related endocrinopathies correlates with tumor response to ICPi therapy.

An unsuspected complication with immune checkpoint blockade: a case report

Background

Immunotherapy treatment with immune-checkpoint blockade has become a new paradigm in cancer treatment. Despite its efficacy, it has also given rise to a new class of adverse events, immune-related adverse events, which may affect any organ, including the thyroid and the pituitary.

Case presentation

We present a case of a 77-year-old Caucasian man with metastatic renal cell carcinoma on immunotherapy treatment who was admitted to our hospital with a severe persistent headache of sudden onset. He had been on corticosteroid therapy for 10 days for suspected immune-related thyroiditis. The patient had tachycardia and mild diarrhea, and his thyroid function tests were compatible with subclinical hyperthyroidism with a suppressed thyroid-stimulating hormone level of 0.01 μIU/ml (0.4–4.5), a raised free T4 level of 2.17 ng/dl (0.7–1.9), and a free T3 level of 4.66 pg/ml (2.27–5). Computed tomography and magnetic resonance imaging revealed an enlargement of the pituitary gland compatible with macroadenoma. In the face of a probable immune-related hypophysitis, high-dose corticosteroid treatment was started. A posterior hormonal evaluation revealed secondary hypothyroidism with a suppressed thyroid-stimulating hormone level of 0.11 μIU/ml (0.4–4.5) and low thyroid hormones, a normal free T4 level of 1.02 ng/dl (0.7–1.9), and a low free T3 level of 1.53 pg/ml (2.27–5). These new findings suggested central hypothyroidism possibly due to pituitary apoplexy as a complication of the macroadenoma. Therefore, levothyroxine substitution was started along with the previously started corticosteroid therapy. The patient’s headache and asthenia gradually resolved, and after a few days, he was released from the hospital with levothyroxine substitution and corticosteroid tapering.

Conclusions

This case emphasizes the importance of the differential diagnosis when dealing with patients on immune checkpoint inhibitors because other non-immune-related events may present. Our patient was finally diagnosed with immune-related hyperthyroidism and a concurrent pituitary macroadenoma. This case also highlights the importance of a prompt start of corticosteroid therapy once immune-related adverse events such as hypophysitis are suspected, because otherwise the outcome would be fatal.

Long-term and late treatment consequences: endocrine and metabolic effects

PURPOSE OF REVIEW

Cancer therapies often result in the 'late effect of cancer treatment' whereby secondary health complications emerge years after radiotherapy and chemotherapy. This review focuses on endocrine and metabolic consequences in adult cancer survivors as late treatment effects.

RECENT FINDINGS

Endocrine and metabolic disorders are among the most common late effects. Endocrine disorders include hypopituitarism, which leads to growth hormone deficiency, hypogonadism, adrenal insufficiency and hypothyroidism and related clinical manifestations. Hypogonadism in particular is associated with a wide range of health complications requiring input from the like of endocrine and fertility specialists. Immune checkpoint inhibitors are novel anticancer agents, some of which are uniquely associated with hypophysitis which requires early recognition and management, including steroid replacement. Metabolic syndrome, a significant risk for cardiovascular disease, is highly prevalent. Although the effects of cranial irradiation on the hypothalamic-pituitary system are more apparent, the relationship between chemotherapy and endocrine/metabolic disorders remains to be elucidated. There exist published guidelines for monitoring endocrine and cardiometabolic risk in cancer survivors, but the extent of monitoring appears insufficient.

SUMMARY

Regular monitoring and early management of endocrine/metabolic disorders is required to prevent the elevated rates of health complications after cancer treatment, and thereby improve cancer survivorship.

The spectrum, incidence, kinetics and management of endocrinopathies with immune checkpoint inhibitors for metastatic melanoma

OBJECTIVE

Endocrine immune-related adverse events (endocrinopathies) are increasingly prevalent with the use of immune checkpoint inhibitors for the treatment of metastatic melanoma and other malignancies. There are no evidence-based guidelines for the screening or management of such patients. To describe the spectrum, incidence, kinetics and management of endocrinopathies with immune checkpoint inhibitors.

DESIGN

A prospective study conducted at Melanoma Institute Australia between April 2014 and October 2015.

METHODS

A total of 177 patients were treated with (a) ipilimumab (n = 15), (b) anti-PD-1 (nivolumab, pembrolizumab) (n = 103) or (c) combination ipilimumab and anti-PD-1 (n = 59) and were screened and managed for the subsequent endocrinopathies. The main outcome measures were the incidence and kinetics of endocrinopathy by immunotherapy drug class.

RESULTS

Thirty-one patients (18%) developed an endocrine immune-related adverse event (thyroid dysfunction: 14%, hypophysitis: 6% and autoimmune diabetes: 0.6%). Combination immunotherapy was more likely to result in a single or multiple endocrinopathy compared to anti-PD-1 monotherapy (27% vs 9% and 7% vs 0% respectively, P < 0.01). Endocrinopathies occurred after a median of 8 weeks from treatment commencement (range: 12-225 days), with combination immunotherapy resulting in significantly earlier onset compared to ipilimumab (median: 30 vs 76 days, P = 0.046). The majority of endocrinopathies were identified in asymptomatic patients with hormonal screening. There were no baseline predictors for endocrinopathy.

CONCLUSIONS

Combination immunotherapy has a greater risk of development of endocrinopathy compared to anti-PD-1 monotherapy. Regular biochemical profiling of patients, particularly within the first twelve weeks, results in early detection of endocrinopathy to minimise morbidity.

Hypophysitis: Nursing Management of Immune-Related Adverse Events

Immunotherapy can treat cancer and prevent future cancer relapse by enhancing the body's immune system. With novel immunotherapeutic agents like checkpoint inhibitors come unique immune-related adverse events. Hypophysitis, one of the lesser known immune-related complications, may be observed in patients receiving checkpoint inhibitors. Although the acute symptoms of immune-related hypophysitis may be managed with attentive monitoring and high-dose corticosteroids, lifelong hormone substitution therapy may be warranted. Oncology nurses are responsible for educating themselves and their patients on the complications of immunotherapy.
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Cancer immunotherapy - immune checkpoint blockade and associated endocrinopathies

Advances in cancer therapy in the past few years include the development of medications that modulate immune checkpoint proteins. Cytotoxic T-lymphocyte antigen 4 (CTLA4) and programmed cell death protein 1 (PD1) are two co-inhibitory receptors that are expressed on activated T cells against which therapeutic blocking antibodies have reached routine clinical use. Immune checkpoint blockade can induce inflammatory adverse effects, termed immune-related adverse events (IRAEs), which resemble autoimmune disease. In this Review, we describe the current data regarding immune-related endocrinopathies, including hypophysitis, thyroid dysfunction and diabetes mellitus. We discuss the clinical management of these endocrinopathies within the context of our current understanding of the mechanisms of IRAEs.

Xanthomatous Hypophysitis Is Associated with Ruptured Rathke's Cleft Cyst

Xanthomatous hypophysitis is a rare inflammatory disease of the pituitary gland that can mimic a neoplastic lesion clinically and radiologically. Its pathogenesis remains largely unknown, although recent evidence suggests that pituitary inflammation may occur as a secondary reaction to mucous content released from a ruptured cyst. In a series of 1221 pituitary specimens, we identified seven cases of xanthomatous hypophysitis. Six patients had complete radiological and biochemical workup preoperatively: a cystic-appearing pituitary mass was identified in all six patients (100%) with a mean size of 2.0 cm (range 1.4-2.5 cm) on imaging, and pituitary endocrine dysfunction was noted in five patients (83.3%). In all cases, the pituitary mass was resected through an endoscopic transsphenoidal approach. Pathological examination revealed the presence of foamy macrophages admixed with variable amounts of giant cells and chronic inflammatory cells, confirming the diagnosis of xanthomatous hypophysitis. Additionally, all cases presented with concurrent findings of ruptured Rathke's cleft cyst, with the exception of one patient who had previous surgery for a Rathke's cleft cyst, followed by recurrence and diagnosis of xanthomatous hypophysitis. While accurate distinction of hypophysitis from a pituitary neoplasm can be problematic in the preoperative setting, the identification of a cystic lesion in the sella turcica should raise the possibility of such an entity in the clinical and radiological differential diagnosis. The current series provides further evidence that xanthomatous hypophysitis predominantly occurs as a secondary reaction to a ruptured Rathke's cleft cyst; thus, it is best classified as a secondary (reactive) hypophysitis.

Genetic risk analysis of a patient with fulminant autoimmune type 1 diabetes mellitus secondary to combination ipilimumab and nivolumab immunotherapy

BACKGROUND

Checkpoint inhibitor immunotherapy is becoming an effective treatment modality for an increasing number of malignancies. As a result, autoinflammatory side-effects are also being observed more commonly in the clinic. We are currently unable to predict which patients will develop more severe toxicities associated with these treatment regimens.

CASE PRESENTATION

We present a patient with stage IV melanoma that developed rapid onset autoimmune type 1 diabetes (T1D) in response to combination ipilimumab and nivolumab immunotherapy. At the time of the patient's presentation with diabetes ketoacidosis, a confirmed anti-GAD antibody seroconversion was noted. Longer-term follow-up of this patient has demonstrated a durable complete response based on PET CT imaging along with a persistently undetectable C-peptide level. Single nucleotide polymorphism gene sequencing and HLA risk allele analysis has revealed the patient to lack any established genetic predisposition to the development of autoimmune T1D.

CONCLUSIONS

While larger studies are necessary to better understand the role of genetic risk factors for the development of autoimmune toxicities in those patients undergoing checkpoint inhibitor immunotherapy, these results suggest that pre-screening patients for known T1D risk alleles may not be indicated. Additional investigation is needed to determine whether an approach such as T cell receptor clonotypic analysis to identify the presence of autoreactive T cell clones may be an effective approach for predicting which patients are at risk for the development of autoinflammatory toxicities while undergoing checkpoint inhibitor immunotherapy.

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

BACKGROUND

Ipilimumab (Yervoy; Bristol-Myers Squibb) is a novel fully humanised monoclonal antibody that blocks cytotoxic T-lymphocyte antigen 4, an immune checkpoint molecule, to augment anti-tumour T-cell responses. It is associated with significant immune-related side-effects including hypophysitis.

AIM

We reviewed the clinical and biochemical characteristics of 10 patients with ipilimumab-induced hypophysitis (IH), and developed guidelines for the early detection and management of IH based on our experiences at three major teaching hospitals in Sydney.

METHODS

All patients were evaluated at the Crown Princess Mary Cancer Centre and Department of Endocrinology, Westmead Hospital, Department of Endocrinology, Royal Prince Alfred Hospital, the Melanoma Institute Australia and Macarthur Cancer Therapy Centre, Campbelltown Hospital from 2010 to 2014. Relevant data were extracted by review of medical records. Main outcome measures included clinical features, hormone profile and radiological findings associated with IH, and presence of pituitary recovery.

RESULTS

Ten patients were identified with IH. In four patients who underwent monitoring of plasma cortisol, there was a fall in levels in the weeks prior to presentation. The pituitary-adrenal and pituitary-thyroid axes were affected in the majority of patients, with the need for physiological hormone replacement. Imaging abnormalities were identified in five of 10 patients, and resolved without high-dose glucocorticoid therapy. To date, all patients remain on levothyroxine and hydrocortisone replacement, where appropriate.

CONCLUSIONS

There is significant morbidity associated with development of IH. We suggest guidelines to assist with early recognition and therapeutic intervention.

Metastatic melanoma: Pathologic characterization, current treatment, and complications of therapy

Metastatic melanoma (MM) has the potential to involve virtually any anatomical site, and it also has a wide spectrum of histological appearances. General clinicopathologic data pertaining to MM are presented in this review, together with a discussion of its differential diagnosis and therapy. "Biological" agents used in the treatment of melanoma are considered, along with the pathological features of the complications that they may cause.

Immune-mediated adverse events of anticytotoxic T lymphocyte-associated antigen 4 antibody therapy in metastatic melanoma

Ipilimumab, an antibody that blocks cytotoxic T lymphocyte-associated antigen 4 (CTLA-4; CD152), was approved by the Food and Drug Administration in 2011 for the treatment of unresectable stage III or IV malignant melanoma. Although the addition of this particular immunotherapy has broadened treatment options, immune-related adverse events (irAEs) are associated with ipilimumab therapy, including dermatologic effects, colitis and diarrhea, endocrine effects, hepatotoxicity, ocular effects, renal effects, neurologic effects, and others. In this article, a critical evaluation of the underlying mechanisms of irAEs associated with anti-CTLA-4 therapy is presented. Additionally, potentially beneficial effects of combinational therapies to alleviate ipilimumab-induced irAEs in malignant melanoma are discussed. Future research is warranted to elucidate the efficacy of such combination therapies and specific biomarkers that would help to predict a clinical response to ipilimumab in patients with malignant melanoma.

Ipilimumab-induced hypophysitis: review of the literature

PURPOSE

Ipilimumab is a human monoclonal antibody against cytotoxic T-lymphocyte antigen 4 available as an immunotherapy mainly for advanced melanoma. It induces an activation of T cells, resulting in an immune-mediated anti-tumor response and also immune-related adverse events, including hypophysitis. The aim of this review is to identify and discuss features concerning ipilimumab-induced hypophysitis (IIH).

DESIGN

A MEDLINE research of all years of publication of IIH was conducted. We gathered information regarding clinical, radiologic and laboratory features of 71 cases recorded in the literature.

RESULTS

In our review, IIH was more frequent among older and male patients. Fatigue and headache were the most frequent initial clinical manifestations of IIH and enlargement of the pituitary gland at MRI was present in the majority of patients. Those who received more than 3 cycles of ipilimumab had more fatigue (p = 0.04) and arthritis (p = 0.04). Adrenal insufficiency was more prevalent in men (p = 0.007). Glucocorticoid therapy and hormone replacement were required in most patients and pituitary function recovery was uncommon. Low prolactin at diagnosis tended to predict permanent pituitary dysfunction (p = 0.07).

CONCLUSION

Hypopituitarism as a consequence of IIH, if not promptly recognized, can lead to potentially fatal events, such as adrenal insufficiency. IIH can be easily managed with glucocorticoids and hormonal replacement; therefore, physicians should be familiar with the key aspects of this condition. More studies to develop screening protocols and therapeutic intervention algorithms should be performed to decrease morbidity related to IIH.

(18)F-FDG PET/CT and Melanoma: Staging, Immune Modulation and Mutation-Targeted Therapy Assessment, and Prognosis

OBJECTIVE

Monoclonal antibodies that target the programmed cell death 1 (PD-1) immune checkpoint protein and its associated ligands, PD-L1 and PD-L2, and targeted inhibitors of mutated signal transduction molecules such as BRAF inhibitors show immense promise in treating patients with melanoma. We discuss the use of (18)F-FDG PET/CT for assessing therapy effectiveness, staging advanced disease, and determining prognosis of patients with melanoma.

CONCLUSION

FDG PET/CT is useful in staging disease, assessing therapy, and determining prognosis in patients with melanoma.

Hypophysitis: a single-center case series

PURPOSE

The authors review their treatment experience and summarize clinical outcomes for patients with hypophysitis over the past 15 years.

METHODS

A retrospective analysis was conducted on patients with lymphocytic, granulomatous or IgG4-related hypophysitis treated from 1997 to 2014 at a single academic center. Patients' medical records were reviewed and binary logistic regression analysis was used to assess whether various clinical parameters were associated with improved outcomes including endocrine function, radiographic appearance and disease recurrence.

RESULTS

Twenty-one patients (13 women and 8 men) were identified with a median diagnosis age of 37.4 years. All but two patients (90%) were diagnosed histopathologically and the remaining two were diagnosed clinically with lymphocytic hypophysitis. 16 patients (76%) had lymphocytic hypophysitis, 3 (14%) had granulomatous hypophysitis, 1 (5%) had IgG4-related hypophysitis and 1 (5%) had mixed lymphocytic-granulomatous. Patients presented with various symptoms of expanding sellar mass with most common signs including headache (57%), polyuria/polydipsia (52%), vision changes (52%) and amenorrhea or decreased libido (48%). Pre-treatment endocrine evaluation revealed that 12 (57%) patients had complete anterior hypopituitarism, 11 patients (52%) had diabetes insipidus, ten patients (48%) had mild hyperprolactinemia and three patients (14%) had isolated endocrine axis deficiencies with partial gland function. We observed a broad diversity in pre-treatment imaging with common findings including uniform contrast enhancement (62%), thickened infundibulum (57%) and loss of hypophysis bright spot on T1 imaging (43%). Patients were treated with steroids and hormone supplementation as needed. 16 patients (76%) had recorded post-treatment MRI scans which revealed that half had radiographic improvement and half had stable or worsened post-treatment imaging. Only female gender was found to significantly predict improved odds of post-steroid radiographic improvement. For post-treatment endocrine evaluation, six patients (29%) did not have an evaluation on record, four patients (19%) had some improvement in at least one axis, seven patients (33%) had stable but non-worsened endocrine function and four patients (19%) had worsened endocrine function post-steroids.

CONCLUSIONS

Hypophysitis is an increasingly recognized diagnosis that can present with a broad array of radiographic and clinical features. Surgical biopsy can be helpful to make definitive diagnosis and may guide treatment decision-making.

The Essential Role of Circulating Thyroglobulin in Maintaining Dominance of Natural Regulatory T Cell Function to Prevent Autoimmune Thyroiditis

Several key findings from the late 1960s to mid-1970s regarding thyroid hormone metabolism and circulating thyroglobulin composition converged with studies pertaining to the role of T lymphocytes in autoimmune thyroiditis. These studies cemented the foundation for subsequent investigations into the existence and antigenic specificity of thymus-derived natural regulatory T cells (nTregs). These nTregs prevented the development of autoimmune thyroiditis, despite the ever-present genetic predisposition, autoantigen (thyroglobulin), and thyroglobulin-reactive T cells. Guided by the hypothalamus-pituitary-thyroid axis as a fixed set-point regulator in thyroid hormone metabolism, we used a murine model and compared at key junctures the capacity of circulating thyroglobulin level (raised by thyroid-stimulating hormone or exogenous thyroglobulin administration) to strengthen self-tolerance and resist autoimmune thyroiditis. The findings clearly demonstrated an essential role for raised circulating thyroglobulin levels in maintaining the dominance of nTreg function and inhibiting thyroid autoimmunity. Subsequent identification of thyroglobulin-specific nTregs as CD4(+)CD25(+)Foxp3(+) in the early 2000s enabled the examination of probable mechanisms of nTreg function. We observed that whenever nTreg function was perturbed by immunotherapeutic measures, opportunistic autoimmune disorders invariably surfaced. This review highlights the step-wise progression of applying insights from endocrinologic and immunologic studies to advance our understanding of the clonal balance between natural regulatory and autoreactive T cells. Moreover, we focus on how tilting the balance in favor of maintaining peripheral tolerance could be achieved. Thus, murine autoimmune thyroiditis has served as a unique model capable of closely simulating natural physiologic conditions.

Effect of cancer treatment on hypothalamic-pituitary function

The past 30 years have seen a great improvement in survival of children and young adults treated for cancer. Cancer treatment can put patients at risk of health problems that can develop many years later, most commonly affecting the endocrine system. Patients treated with cranial radiotherapy often develop dysfunction of the hypothalamic-pituitary axis. A characteristic pattern of hormone deficiencies develops over several years. Growth hormone is disrupted most often, followed by gonadal, adrenal, and thyroid hormones, leading to abnormal growth and puberty in children, and affecting general wellbeing and fertility in adults. The severity and rate of development of hypopituitarism is determined by the dose of radiotherapy delivered to the hypothalamic-pituitary axis. Individual growth hormone deficiencies can develop after a dose as low as 10 Gy, whereas multiple hormone deficiencies are common after 60 Gy. New techniques in radiotherapy aim to reduce the effect on the hypothalamic-pituitary axis by minimising the dose received. Patients taking cytotoxic drugs do not often develop overt hypopituitarism, although the effect of radiotherapy might be enhanced. The exception is adrenal insufficiency caused by glucocorticosteroids which, although transient, can be life-threatening. New biological drugs to treat cancer can cause autoimmune hypophysitis and hypopituitarism; therefore, oncologists and endocrinologists should be vigilant and work together to optimise patient outcomes.

Adverse events of monoclonal antibodies used for cancer therapy

In 1997, the first monoclonal antibody (MoAb), the chimeric anti-CD20 molecule rituximab, was approved by the US Food and Drug administration for use in cancer patients. Since then, the panel of MoAbs that are approved by international regulatory agencies for the treatment of hematopoietic and solid malignancies has continued to expand, currently encompassing a stunning amount of 20 distinct molecules for 11 targets. We provide a brief scientific background on the use of MoAbs in cancer therapy, review all types of monoclonal antibodies-related adverse events (e.g., allergy, immune-related adverse events, cardiovascular adverse events, and pulmonary adverse events), and discuss the mechanism and treatment of adverse events.

Early recognition of ipilimumab-related autoimmune hypophysitis in patients with metastatic melanoma: Case studies and recommendations for management

Ipilimumab is a human anti-CTLA-4 monoclonal antibody recently approved for the treatment of advanced melanoma. Stimulation of T-cell activity unmasks antitumor activity, but can cause immune-related adverse events. Autoimmune hypophysitis is of particular importance because its presentation can be subtle but life threatening. We present two cases where early recognition of ipilimumab-related autoimmune hypophysitis led to timely intervention and low subsequent morbidity, without compromise of antitumor effects. We provide recommendations for detection and management of this potentially life-threatening complication of ipilimumab.

Long-term follow-up of ipilimumab-induced hypophysitis, a common adverse event of the anti-CTLA-4 antibody in melanoma

OBJECTIVE

Few data are published on the long-term follow-up of ipilimumab-induced hypophysitis, a cytotoxic T-lymphocyte antigen 4 antibody. We characterized hypophysitis in terms of clinical signs, endocrinological profile, and imaging at diagnosis and during a long-term follow-up.

DESIGN AND PATIENTS

Fifteen patients, treated for malignant melanoma and who presented ipilimumab-induced hypophysitis, were observed between June 2006 and August 2012 in Timone Hospital, Marseille.

METHODS

Symptoms, pituitary function, and pituitary imaging at diagnosis of hypophysitis and during the follow-up were recorded.

RESULTS

Of 131 patients treated with ipilimumab or a placebo, 15 patients (10 mg/kg in 11/15) presented with hypophysitis (≥11.5%) at 9.5±5.9 weeks (mean±s.d.) after treatment start, occurring in 66% after the third infusion. The main initial symptoms were headache (n=13) and asthenia (n=11). All patients but one had at least one hormonal defect: thyrotroph (n=13), gonadotroph (n=12), or corticotroph (n=11) deficiencies. None had diabetes insipidus. Pituitary imaging showed a moderately enlarged gland in 12 patients. Clinical symptoms improved rapidly on high-dose glucocorticoids (n=11) or physiological replacement doses (n=4). At the end of follow-up (median 33.6 months, range 7-53.5), corticotroph deficiency remained in 13 patients, 11 recovered thyrotroph and ten gonadotroph functions. Pituitary imaging remained abnormal in 11 patients.

CONCLUSION

Ipilimumab-induced hypophysitis is a common side-effect with frequent hormonal deficiencies at diagnosis. Usually, hormonal deficiencies improved, except for corticotroph function. Patients receiving these immunomodulatory therapies should be closely monitored especially by systematic baseline hormone measurements after the third infusion and remain at a risk of adrenal insufficiency in the long-term.

Anticytotoxic T-lymphocyte antigen-4 induced autoimmune hypophysitis: a case report and literature review

Objective. We describe a case of autoimmune hypophysitis induced by the anticytotoxic T-lymphocyte antigen-4 (CTLA-4) agent, ipilimumab. Methods. Case presentation and review of the literature. Results. Autoimmune hypophysitis, a previously described rare disorder, is being recognized more frequently as a side effect of novel immunomodulatory agents used in the treatment of malignancies such as melanoma. CTLA-4 agents are associated with immune-related adverse effects (irAE) which occur as a result of activation (or lack of inactivation) of the immune response. This impacts not only malignant cells but also different host organ-systems. Autoimmune hypophysitis is one of several endocrinopathies associated with these agents. Conclusion. It is important that endocrinologists become familiar with the endocrinopathies, such as autoimmune hypophysitis, associated with new immunomodulator agents which are being used with increasing frequency to treat a variety of malignancies.

Ipilimumab, not just another anti-cancer therapy: hypophysitis as side effect illustrated by four case-reports

Ipilimumab is a monoclonal antibody that blocks cytotoxic T-lymphocyte antigen4 (CTLA-4), an inhibitory molecule typically expressed on T cells. Blockade of CTLA-4 induces an overall activation of T cells, including an immune-mediated anti-tumour response. Unfortunately, this broad T cell stimulation also causes immune-related adverse events (irAEs), such as dermatitis, colitis, hepatitis and hypophysitis. Ipilimumab is currently available in Belgium as a second line of treatment for patients with advanced melanoma, and is used at a dose of 3 mg/kg of body weight, although higher doses were previously used (up to 10 mg/kg). We performed a retrospective analysis to identify melanoma patients treated with ipilimumab at the Ghent University Hospital between 2010 and 2013. Data on symptoms, stage and timing of ipilimumab, response and adverse events were collected with a special attention to endocrine disturbances, going from a limited involvement of one endocrine axis to development of a hypophysitis. We identified a total of 39 patients with stage III (No. = 7) or stage IV (No. = 32) melanoma, who received a dose of 3 (No. = 31) or 10 (No. = 8) mg/kg. Six patients developed a severe form of irAEs, including one case of colitis (2 %), one case of sarcoidosis (2 %) and 4 cases (10 %) of hypophysitis. Hypophysitis developed between the second and fourth cycle of ipilimumab administration and was independent of the dose used. We describe four cases of involvement of the pituitary gland during treatment with ipilimumab. When managed with vigilant monitoring and high-dose corticosteroids, the acute symptoms resolve, but lifelong hormone substitution therapy can be necessary. Involvement of the pituitary axes is a severe side effect of treatment with ipilimumab with an urgent need for the correct medical intervention.

Ipilimumab-induced autoimmune hypophysitis: a differential for sellar mass lesions

Autoimmune hypophysitis (AH) has been previously described in a typical demographic population, primarily women in the reproductive age group and perinatal period. The era of immune modulation using anti-cytotoxic T-lymphocyte-associated antigen 4 biological therapy (ipilimumab) against advanced cancers like metastatic melanomas has now resulted in a new form of hypophysitis being increasingly recognised under a spectrum of immune-related adverse events. Drug-related AH often presents with subtle symptoms and a pituitary mass, with the potential for fatality necessitating wide awareness and a high index of clinical suspicion given that it is usually treatable. We describe below two cases of AH within the last three months at our centre, which were treated with different regimens and produced good endocrine outcomes.

64Cu-DOTA-anti-CTLA-4 mAb enabled PET visualization of CTLA-4 on the T-cell infiltrating tumor tissues

Cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) targeted therapy by anti-CTLA-4 monoclonal antibody (mAb) is highly effective in cancer patients. However, it is extremely expensive and potentially produces autoimmune-related adverse effects. Therefore, the development of a method to evaluate CTLA-4 expression prior to CTLA-4-targeted therapy is expected to open doors to evidence-based and cost-efficient medical care and to avoid adverse effects brought about by ineffective therapy. In this study, we aimed to develop a molecular imaging probe for CTLA-4 visualization in tumor. First, we examined CTLA-4 expression in normal colon tissues, cultured CT26 cells, and CT26 tumor tissues from tumor-bearing BALB/c mice and BALB/c nude mice by reverse transcription polymerase chain reaction (RT-PCR) analysis and confirmed whether CTLA-4 is strongly expressed in CT26 tumor tissues. Second, we newly synthesized ⁶⁴Cu-1,4,7,10-tetraazacyclododecane-N,N′,N″,N‴-tetraacetic acid-anti-mouse CTLA-4 mAb (⁶⁴Cu-DOTA-anti-CTLA-4 mAb) and evaluated its usefulness in positron emission tomography (PET) and ex-vivo biodistribution analysis in CT26-bearing BALB/c mice. High CTLA-4 expression was confirmed in the CT26 tumor tissues of tumor-bearing BALB/c mice. However, CTLA-4 expression was extremely low in the cultured CT26 cells and the CT26 tumor tissues of tumor-bearing BALB/c nude mice. The results suggested that T cells were responsible for the high CTLA-4 expression. Furthermore, ⁶⁴Cu-DOTA-anti-CTLA-4 mAb displayed significantly high accumulation in the CT26 tumor, thereby realizing non-invasive CTLA-4 visualization in the tumor. Together, the results indicate that ⁶⁴Cu-DOTA-anti-CTLA-4 mAb would be useful for the evaluation of CTLA-4 expression in tumor.

Update on benefit of immunotherapy and targeted therapy in melanoma: the changing landscape

Malignant melanoma is on the rise. There have been recent advances in targeted agents and immunotherapies that have improved the management and treatment of patients with advanced melanoma. This review discusses the clinical efficacy and unique side effects of targeted immunotherapy and the role of predictive biomarkers in better selection of patients who would derive most benefit from specific treatments. Additionally, this review addresses concerns about the best sequencing algorithms for the currently available targeted agents. By thoroughly and extensively researching through PubMed and the American Society of Clinical Oncology, 69 published articles and abstracts were identified as addressing topics related to malignant melanoma and immunotherapy. The research was divided into subcategories discussing cytokine-based therapy, immunotherapy, molecularly targeted agents, other novel targeted agents, and combination regimens for malignant melanoma. New immune checkpoint inhibitors and targeted agents are able to improve immune-mediated regulatory effects against tumors and, specifically in advanced melanoma, are associated with improvement in overall survival. These new agents have distinct side effects that are often controlled and reversed with dose reductions and/or use of corticosteroids. Currently, there are clinical trials underway to assess the role of combination therapy, whereas other trials are focusing on devising algorithms to delineate how best to sequentially administer these drugs. Although there has been tremendous progress in the management of advanced melanoma with immunotherapy and targeted agents, there is still much to be learned about clinically useful predictive biomarkers and combination therapies as well as how to administer these agents safely.

Opportunistic Autoimmune Disorders Potentiated by Immune-Checkpoint Inhibitors Anti-CTLA-4 and Anti-PD-1

To improve the efficacy of immunotherapy for cancer and autoimmune diseases, recent ongoing and completed clinical trials have focused on specific targets to redirect the immune network toward eradicating a variety of tumors and ameliorating the self-destructive process. In a previous review, both systemic immunomodulators and monoclonal antibodies (mAbs), anti-CTLA-4, and anti-CD52, were discussed regarding therapeutics and autoimmune sequelae, as well as predisposing factors known to exacerbate immune-related adverse events (irAEs). This review will focus on immune-checkpoint inhibitors, and the data from most clinical trials involve blockade with anti-CTLA-4 such as ipilimumab. However, despite the mild to severe irAEs observed with ipilimumab in ~60% of patients, overall survival (OS) averaged ~22-25% at 3-5 years. To boost OS, other mAbs targeting programed death-1 and its ligand are undergoing clinical trials as monotherapy or dual therapy with anti-CTLA-4. Therapeutic combinations may generate different spectrum of opportunistic autoimmune disorders. To simulate clinical scenarios, we have applied regulatory T cell perturbation to murine models combined to examine the balance between thyroid autoimmunity and tumor-specific immunity.

Endocrine side-effects of anti-cancer drugs: mAbs and pituitary dysfunction: clinical evidence and pathogenic hypotheses

mAbs are established targeted therapies for several diseases, including hematological and solid malignancies. These agents have shown a favorable toxicity profile, but, despite their high selectivity, new typical side-effects have emerged. In cancer patients, pituitary dysfunction may be mainly due to brain metastases or primary tumors and to related surgery and radiotherapy. Anticancer agents may induce hypopituitarism in patients cured for childhood cancers. These agents infrequently affect pituitary function in adult cancer patients. Notably, hypophysitis, a previously very rare disease, has emerged as a distinctive side-effect of ipilimumab and tremelimumab, two mAbs inhibiting the cytotoxic T-lymphocyte antigen-4 receptor, being occasionally seen with nivolumab, another immune checkpoint inhibitor. Enhanced antitumor immunity is the suggested mechanism of action of these drugs and autoimmunity the presumptive mechanism of their toxicity. Recently, ipilimumab has been licensed for the treatment of patients affected by metastatic melanoma. With the expanding use of these drugs, hypophysitis will be progressively encountered by oncologists and endocrinologists in clinical practice. The optimal management of this potentially life-threatening adverse event needs a rapid and timely diagnostic and therapeutic intervention. Hypopituitarism caused by these agents is rarely reversible, requiring prolonged or lifelong substitutive hormonal treatment. Further studies are needed to clarify several clinical and pathogenic aspects of this new form of secondary pituitary dysfunction.

Thyroid dysfunction as an unintended side effect of anticancer drugs

BACKGROUND

Several of the currently used anticancer drugs may variably affect thyroid function, with impairment ranging from modified total but not free concentration of thyroid hormones to overt thyroid disease.

SUMMARY

Cytotoxic agents seem to alter thyroid function in a relatively small proportion of adult patients. Anticancer hormone drugs may mainly alter serum levels of thyroid hormone-binding proteins without clinically relevant thyroid dysfunction. Old immunomodulating drugs, such as interferon-α and interleukin-2, are known to induce variably high incidence of autoimmune thyroid dysfunction. Newer immune checkpoint inhibitors, such as anti-CTLA4 monoclonal antibodies, are responsible for a relatively low incidence of thyroiditis and may induce secondary hypothyroidism resulting from hypophysitis. Central hypothyroidism is a well-recognized side effect of bexarotene. Despite their inherent selectivity, tyrosine kinase inhibitors may cause high rates of thyroid dysfunction. Notably, thyroid toxicity seems to be restricted to tyrosine kinase inhibitors targeting key kinase-receptors in angiogenic pathways, but not other kinase-receptors (e.g., epidermal growth factor receptors family or c-KIT). In addition, a number of these agents may also increase the levothyroxine requirement in thyroidectomized patients.

CONCLUSIONS

The pathophysiology of thyroid toxicity induced by many anticancer agents is not fully clarified and for others it remains speculative. Thyroid dysfunction induced by anticancer agents is generally manageable and dose reduction or discontinuation of these agents is not required. The prognostic relevance of thyroid autoimmunity, overt and subclinical hypothyroidism induced by anticancer drugs, the value of thyroid hormone replacement in individuals with abnormal thyrotropin following anticancer systemic therapy, and the correct timing of replacement therapy in cancer patients need to be defined more accurately in well-powered prospective clinical trials.

Update on hypophysitis and TTF-1 expressing sellar region masses

This article reviews recent literature on sellar region masses that most closely mimic nonsecretory pituitary adenomas: hypophysitis, pituicytoma, spindle cell oncocytoma, and granular cell tumor of neurohypophysis. Even today, these four entities often cannot be confidently distinguished from each other clinically or by preoperative neuroimaging features. Thus, they often come to biopsy/surgical resection and require tissue confirmation of diagnosis. Causes of secondary and primary hypophysitis will be discussed, including two newly described types, IgG4 plasma cell hypophysitis and hypophysitis caused by anti-cytotoxic T-lymphocyte antigen 4 antibody therapy for cancer. For the neoplastic conditions, emphasis will be placed on literature that has emerged since these entities were first codified in the 2007 World Health Organization fascicle. The finding that immunohistochemical staining for thyroid transcription factor-1 is shared by pituicytoma, spindle cell oncocytoma, and granular cell tumor of neurohypophysis suggests common lineage and explains why histological overlap can be encountered. We incorporate our own experiences over the last 30 years from two referral institutions with specialty practices in pituitary region masses.