Introduction to expert opinion on endocrine complications of new anticancer therapies

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.

Endocrine complications of immunotherapies: a review

Use of immune checkpoint inhibitors in cancer treatment has increased vastly over the past decade, as both single and combination agent therapies. While having a positive impact on survival rates, adverse effects have been noted, with endocrine effects in around 10% of patients. Thyroid disease and hypophysitis are the most commonly encountered, with diabetes mellitus and primary adrenal insufficiency also reported, as well as more rare endocrinopathies. Patient and clinician education to raise awareness of these effects, as well as regular monitoring to enable early recognition, diagnosis and prompt treatment of the immune side effects, are key. In this review, we discuss the aetiology, presentation and management of the endocrine complications of immunotherapies that are relevant to the general physician, as well as highlighting important areas where further research is still needed.

Endocrine complications of new anticancer therapies

Studying and analyzing of complex molecular mechanisms and immunological processes of cancer enables oncology to introduce new cancer therapies. In the treatment of cancer, we successively increase the use of targeted therapies with tyrosine kinase inhibitors and mTOR inhibitors and immunotherapy using checkpoint inhibitors CTLA-4 (cytotoxic T-cell antigen-4) and PD-1/PD-L1 (programmed death receptor 1/programmed death ligand 1). New anticancer drugs gradually replace conventional chemotherapy and have already found application in the treatment of many cancers, including thyroid cancer, hepatocellular carcinoma, non-small cell lung cancer, kidney cancer, bladder cancer, melanoma, breast cancer, acute and chronic myelogenous leukemia. The use of these drugs is less toxic than classical chemotherapy, but it can cause gastrointestinal, cardiovascular, respiratory, skin and endocrine complications. Most of the side effects of new cancer therapies are mild and moderate disorders, however some might be severe and life-threatening. Endocrinopathies are one of the more common side effects of these treatments. They can affect many endocrine glands (pituitary, thyroid, parathyroid, adrenal, pancreas) and cause both transient and permanent disorders.

[Thyroiditis: What's new in 2019?]

Thyroiditis is a frequent and mostly benign disease that can sometimes disrupt the thyroid balance. Their diagnosis, as well as their aetiology, is a necessary step in the management of the patients. Painful thyroiditis includes acute thyroiditis of infectious origin and subacute thyroiditis. The first one can be treated by antibiotics or antifungals depending on the germ found. The second one will be treated with non-steroidal anti-inflammatory drugs or corticosteroids. In cases of Hashimoto's thyroiditis with overt hypothyroidism, replacement therapy with L-thyroxine will be adapted to the TSH level. As amiodarone treatment provides dysthyroidism, the thyroid status should be monitored regularly. Hypothyroidism will be treated using thyroid replacement therapy. Hyperthyroidism imposes a stop of amiodarone when it is possible. Treatment with synthetic antithyroid drugs (propyl-thio-uracil) or corticosteroids could be used whether there is an underlying thyroid disease or not. Immunotherapies with anti-PD-1/PDL1 or anti-CTLA-4 can also provide dysthyroidism. A monitoring of the thyroid assessment needs to be done in these patients, even if there are no clinical signs, which are not very specific in this context. The treatment of hypothyroidism will be based on thyroid replacement therapy according to the TSH level and the presence or absence of anti-TPO antibodies. Treatment of symptomatic hyperthyroidism may involve a prescription of beta-blockers, or synthetic antithyroid drugs in case of positive anti-TSH receptor antibodies. In all cases, it is desirable to contact an endocrinologist to confirm the diagnosis hypothesis and to decide on a suitable treatment.

[Immunotherapy-induced endocrinopathies: Insights from the 2018 French Endocrine Society Guidelines]

The management of cancer patients has changed due to the considerably more frequent use of immune checkpoint inhibitors (ICPI). However, the use of ICPI has a risk of side-effects, particularly endocrine toxicity. Since the indications for ICPI are constantly expanding due to their efficacy, it is important that endocrinologists and oncologists know how to look for this type of toxicity and how to treat it when it arises. In view of this, the French Endocrine Society initiated the formulation of a guidance document on ICPI-related endocrine toxicity. In this paper, we summarize the main insights of experts' opinions, from an oncologist viewpoint: initial screening, monitoring, emergency situations for which immediate management by the oncologist is crucial, as well as the roles of the interactions between oncologists and endocrinologists. These points will be detailed for each endocrinopathy, i.e., dysthyroidism, hypophysitis, fulminant diabetes and primary adrenal insufficiency. In each chapter, expert opinion will be given on the diagnosis, management and monitoring for each complication. Finally, the CTCAE (Common terminology criteria for adverse events) recommendations will be discussed in view of the relatively easy management of such endocrine side-effects.

French Endocrine Society Guidance on endocrine side effects of immunotherapy

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