Acute Lower Limb Ischaemia and Diabetes in a Patient Treated with Anti-PD1 Monoclonal Antibody for Metastatic Melanoma

Clinically Approved Monoclonal Antibodies-based Immunotherapy: Association With Glycemic Control and Impact Role of Clinical Pharmacist for Cancer Patient Care

PURPOSE

Compared with more conventional, nonspecific therapy options, such as radiotherapy and chemotherapy, monoclonal antibodies (mAbs) constitute a crucial approach of cancer treatment. Multiple autoimmune diseases have been observed during treatment with mAb medications, including autoimmune diabetes mellitus (DM). This study provides a narrative review of clinically approved mAbs in cancer treatment and focuses on the development of hyperglycemia and DM arising from using these therapies. Furthermore, it highlights the critical role of oncology clinical pharmacists in the management of autoimmune DM and patient care while using these medications in an oncology setting.

METHODS

An extensive literature search was conducted using various sources of electronic databases, such as Scopus, Embase, Web of Science, and PubMed, and search engines, such as Google Scholar, for studies on mAb classification, types, mechanisms of action, pharmacokinetic properties, current clinical applications, and the associated common adverse effects with significant recommendations for patient care in an oncology setting, along with focusing on the proposed mechanisms and clinical studies that reported the association of DM after the use of these therapies.

FINDINGS

There are 4 types (murine, chimeric, humanized, and human) and 3 classes (unconjugated, conjugated, and bispecific) of mAbs with several mechanisms of action that can destroy cancer cells, including preventing tumor cell survival cascades, inhibiting tumor growth by interfering with tumor angiogenesis, evading programmed cell death, and bypassing immune checkpoints. However, multiple endocrinopathies, autoimmune diseases, and complications were reported from the use of these medications, including the development of autoimmune DM and diabetic ketoacidosis. These autoimmune disorders were reported most with the use of immune checkpoint inhibitors, including inhibitors of the programmed cell death protein 1 (nivolumab and pembrolizumab), its ligand (atezolizumab, avelumab, and durvalumab), and cytotoxic T-lymphocyte-associated protein 4 (ipilimumab).

IMPLICATIONS

mAbs are considered important approaches for the treatment of many cancer types. However, a high incidence of hyperglycemia, type 1 DM, and diabetic ketoacidosis is observed with the use of these medications, particularly immune checkpoint inhibitors. It is important for oncologic clinical pharmacists to be involved in addressing these autoimmune disorders from the use of these immunotherapies via the provision of patient education, medication adherence support, close monitoring, and follow-up, which will lead to better health-related outcomes and improved patient quality of life.

Immune checkpoint inhibitor-induced cutaneous toxicities: a review of histopathologic and clinical features

Immune checkpoint inhibitors (ICIs) represent an emerging treatment option for a variety of cancer types. Through inhibition of programmed cell death protein 1 (PD-1), programmed cell death ligand 1 (PD-L1), and/or cytotoxic lymphocyte-associated antigen-4 (CTLA-4), ICIs activate the host's immune system causing a heightened anti-tumor response. However, off-target effects of ICIs can result in numerous different immune-related cutaneous adverse events (irCAEs). Beyond impacting quality of life, irCAEs can lead to dose limitations or discontinuation of anti-cancer therapies. Correct diagnosis is necessary for expedient and appropriate management. Skin biopsies are often performed to increase diagnostic accuracy and guide clinical management. An extensive literature review was performed using the PubMed database to identify the reported clinical and histopathologic features of irCAEs. This comprehensive review primarily details the histopathologic features of various irCAEs reported to date. Clinical presentation and immunopathogenesis are also discussed in relation to histopathology.

Clinical characteristics and outcomes of immune checkpoint inhibitor-induced diabetes mellitus

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This article summarized a total of 172 published cases of immune checkpoint inhibitor (ICI)-induced diabetes mellitus (DM).

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Found that glutamic acid decarboxylase antibodies positivity is related to an earlier onset of ICI-induced diabetes and a higher frequency of diabetic ketoacidosis development.

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Presented a case of ICI-induced DM following obvious lipase and amylase elevation and discussed possible relationship between ICI-associated injuries to pancreatic exocrine function and endocrine function.

Objective

To better understand immune checkpoint inhibitor (ICI)-induced diabetes mellitus (DM) in cancer patients.

Design and method

We present a case of ICI-induced diabetic ketoacidosis (DKA) and conduct a systematic review of the PubMed and Web of Science databases up to September 2021 to identify all published cases of ICI-induced diabetes.

Results

In addition to our case, a total of 171 published cases were identified during the literature search. Summary and statistical analyzes were conducted for all 172 cases. The median onset time from ICI initiation to DM diagnosis was 12 weeks (range: 0–122). DKA was present in 67.4% (116/172) of the cases, and low C-peptide levels were detected in 91.8% (123/134), indicating an acute onset of diabetes. Patients with positive glutamic acid decarboxylase antibodies (GADA) had an earlier onset of ICI-induced diabetes (median time 7 weeks vs. 16 weeks for GADA-negative patients, p < 0.001) and a higher frequency of DKA development (82.8 vs. 62.1%, p = 0.006). All but two patients developed insulin-dependent diabetes permanently. Immunotherapy rechallenge was reported in 53 cases after glycemia was well controlled.

Conclusion

ICI-induced DM is a serious adverse event that often presents with life-threatening ketoacidosis. GADA positivity is related to an earlier onset of ICI-induced diabetes and a higher frequency of DKA development. Close monitoring of glucose levels is needed in patients receiving ICI treatment. ICI-induced DM is usually insulin-dependent since damage to β cells is irreversible. On the premise of well-controlled glycemia, immunotherapy rechallenge is feasible.

Is immune checkpoint inhibitor-associated diabetes the same as fulminant type 1 diabetes mellitus?

Pembrolizumab is an anti-cancer drug that targets programmed cell death protein-1 (PD-1) receptors on lymphocytes resulting in their activation against tumour cells. PD-1 receptors are also interspersed in endocrine organs and pembrolizumab use has long been associated with hypophysitis and thyroiditis. Since the introduction of immune checkpoint inhibitors (ICI), several cases of fulminant type 1 diabetes mellitus (FT1DM) have been reported. However, it is unclear if FT1DM and ICI-induced diabetes are the same pathology. We review the existing literature of ICI-induced diabetes to investigate its nature and to what extent it represents type 1A diabetes and/or FT1DM (type 1B diabetes) using an example case. Our review showed that ICI-induced diabetes may be a different entity to FT1DM. Furthermore, there is limited evidence for the management of ICI-induced T1DM. Further research into its pathophysiology will improve management and possibly prevent this burdensome complication.

Sintilimab induced diabetic ketoacidosis in a patient with small cell lung cancer: A case report and literature review

RATIONALE

Sintilimab is a novel programmed cell death receptor-1 (PD-1) inhibitor approved in the treatment of classical Hodgkin's lymphoma and undergoing clinical trials for various malignancies. As a PD-1 inhibitor, sintilimab is known to cause autoimmune adverse events similar to other PD-1 inhibitors. Diabetic ketoacidosis (DKA) is a rare but severe adverse event of this therapy.

PATIENT CONCERNS

We report a case of a 59-year-old man who developed DKA after 5 doses of sintilimab for small cell lung cancer. His fasting glycemia level was 14.07 mmol/L, urine ketone bodies were 4+, arterial blood pH was 7.271, bicarbonate was 12.3 mmol/L, and glycated hemoglobin (HbA1c) was 7.4%. Extended investigations revealed that fasting C-peptide was undetectable (<0.003 nmol/L).

DIAGNOSIS

These laboratory investigations supported the diagnosis of fulminant type 1 diabetes mellitus, but no β-cell related antibodies were positive.

INTERVENTIONS

After remission of DKA, he was treated with insulin therapy to acquire a normalization of glycemia and the disappearance of symptoms.

OUTCOMES

Sintilimab was withheld after 6 cycles and was converted to durvalumab to sustain the therapeutic effect.

LESSONS

This case and associated literature review illustrate the importance of educating and monitoring patients who start PD-1 inhibitor therapy regarding this potentially life-threatening complication.

Nivolumab-caused hyperprogression of diffuse large B-cell lymphoma of the testis and spontaneous remission of type 2 diabetes mellitus in an elderly patient: a case report

Nivolumab has been used in a variety of advanced malignant tumors. Cases of autoimmune diabetes associated with Nivolumab therapy have been reported gradually in recent years. This article reported a case of primary testicular lymphoma in an elderly patient with type 2 diabetes mellitus (T2DM). After treatment with Nivolumab, the primary disease was hyperprogressive disease but the blood glucose was relieved for a long time. Nivolumab may relieve the previous T2DM in diffuse large B-cell lymphoma patients; the potential mechanism needs to be further explored.

Incidence of thromboembolism in patients with melanoma on immune checkpoint inhibitor therapy and its adverse association with survival

BACKGROUND

Thromboembolism (TE) in cancer significantly contributes to morbidity and mortality. Little is known about the incidence of arterial TE (ATE) and venous TE (VTE) in patients with melanoma on immune checkpoint inhibitor (ICI) therapy.

METHODS

We conducted a retrospective cohort study of patients with melanoma receiving ICI from July 2015 through December 2017 at the Cleveland Clinic. TE, including VTE events of deep venous thrombosis, pulmonary embolism, visceral vein thrombosis, and ATE events of myocardial infarction, stroke, peripheral arterial embolism, or transient ischemic attack after ICI initiation were identified. Overall survival (OS) from ICI initiation was estimated by Kaplan-Meier and Cox hazard models; associations between TE, ICI regimen, and clinical risk factors were evaluated using log-rank test.

RESULTS

The study population comprised 228 patients with median age of 65 years (23-91 years), 67% male, and median follow-up of 27.3 months. Pembrolizumab was most commonly used (38.7%), followed by combination of ipilimumab plus nivolumab (29.4%), ipilimumab (20%), and nivolumab (12.3%). Most had stage IV disease (81.1%) and 11% had brain metastases (BM) at treatment initiation. Fifty-one TE events occurred in 47 patients (20.6%), including 37 (16.2%) VTE and 14 (6.1%) ATE. Cumulative incidence of TE after ICI initiation was 9.3% (95% CI: 6.0% to 13.6%) at 6 months, and 16.0% (95% CI: 11.6% to 21.2%) at 12 months. The 6-month and 12-month VTE cumulative incidence rates were higher with combination ICI than single agent (16.7% vs 5.0% and 21.3% vs 9.5%, respectively; p=0.02). Risk factors significantly associated with VTE in multivariate analysis included combination ICI (HR 2.70; 95% CI: 1.28 to 5.70; p=0.009), Khorana Score ≥1 (HR 2.24; 95% CI: 1.06 to 4.74; p=0.03), history of coronary artery disease (HR 2.71; 95% CI: 1.16 to 6.29); p=0.02), and anticoagulation at treatment start (HR 4.14; 95% CI: 1.60 to 10.7; p=0.003). Of patients without BM, OS was worse in patients with TE compared with those without (2-year OS 50.8% vs 71.3%; HR 2.27; 95% CI: 1.36 to 3.79; p=0.002), when adjusted for age and stage.

CONCLUSIONS

ICI is associated with a high incidence of TE in patients with melanoma, with higher rates with combination therapy; TE is associated with substantial worsening of survival. Further studies are needed to identify pathophysiology, biomarkers, and preventive approaches.

Diabetes mellitus induced by immune checkpoint inhibitors

Immune checkpoint inhibitors (ICIs) are widely used in oncology for their favourable antitumor efficacy. ICI therapy is associated with a unique toxicity profile known as immune-related adverse events (irAEs). One such irAE is ICI-related diabetes mellitus (DM), which is relatively uncommon but can become extremely severe, leading to irreversible impairment of β-cells, and even lead to death if not promptly recognised and properly managed. The precise mechanisms of ICI-related DM are not well understood. In this review, we summarise the clinical characteristics, pathophysiology, and management of this adverse effect caused by ICI therapy. Deeper investigation of ICI-related DM may contribute to elucidate the molecular mechanisms of classical type 1 DM.

Acral vascular syndrome during an immune checkpoint inhibitor

Immune checkpoint inhibitors, including antiprogrammed death cell protein 1 (anti-PD-1) and anti cytotoxic T-lymphocyte-associated protein 4 (anti-CTLA-4), have been associated with a range of autoimmune-related side effects since their introduction in cancer treatment. Small vessel digital necrosis, referred to as the acral vascular syndrome, is a rare but serious complication that can result in loss of digits. Here we present a case report of acral vascular syndrome and review possible aetiologies. A 45- year-old woman with invasive ductal carcinoma of the left breast presented to the emergency department during neoadjuvant treatment with carboplatin, docetaxel and pembrolizumab with complaints of severe pain in her right third digit. She had physical findings consistent with ischaemic necrosis and gangrene of the distal phalanx. Angiography demonstrated Raynaud's phenomenon in the distal portion of the digits. Laboratory testing showed a weakly positive RNA polymerase III antibody level. Her case resulted in surgical amputation of her affected digit after partial resolution of symptoms with prednisone, vasodilators and antibiotics.

Immune checkpoint inhibitors and type 1 diabetes mellitus: a case report and systematic review

OBJECTIVE

To better define the rare adverse event (AE) of diabetes mellitus associated with immune checkpoint inhibitors (ICIs).

DESIGN AND METHODS

We report the case of a lung cancer patient with diabetic ketoacidosis (DKA) and autoimmune thyroiditis during pembrolizumab treatment. We provide a systematic review of all published cases (PubMed/Web of Science/Cochrane, through November 2018) of autoimmune diabetes mellitus related to blockade of the cytotoxic T-lymphocyte antigen 4 (CTLA-4)-, programmed cell death 1 (PD-1) receptor or its ligand (PD-L1) or combination (ICI) therapy.

RESULTS

Our literature search identified 90 patient cases (our case excluded). Most patients were treated with anti-PD-1 or anti-PD-L1 as monotherapy (79%) or in combination with CTLA-4 blockade (15%). On average, diabetes mellitus was diagnosed after 4.5 cycles; earlier for combination ICI at 2.7 cycles. Early-onset diabetes mellitus (after one or two cycles) was observed during all treatment regimens. Diabetic ketoacidosis was present in 71%, while elevated lipase levels were detected in 52% (13/25). Islet autoantibodies were positive in 53% of patients with a predominance of glutamic acid decarboxylase antibodies. Susceptible HLA genotypes were present in 65% (mostly DR4). Thyroid dysfunction was the most frequent other endocrine AE at 24% incidence in this patient population.

CONCLUSION

ICI-related diabetes mellitus is a rare but often life-threatening metabolic urgency of which health-care professionals and patients should be aware. Close monitoring of blood glucose and prompt endocrine investigation in case of hyperglycemia is advisable. Predisposing factors such as HLA genotype might explain why some individuals are at risk.

Programmed Cell Death-1 Monoclonal Antibody Therapy and Type 1 Diabetes Mellitus: A Review of the Literature

Two Food and Drug Administration-approved programmed cell death-1 (PD-1) inhibitors, nivolumab (Opdivo®), and pembrolizumab (Keytruda®), are indicated for treatment-resistant malignancies. Inhibition of PD-1 also inhibits T-cell peripheral tolerance, enhancing autoimmunity. Various autoimmune conditions have been reported with the use of these agents, including type 1 diabetes mellitus (T1DM). This article reviews literature regarding the development of T1DM in patients treated with PD-1 inhibitors and identifies strategies for the appropriate identification, monitoring, and follow-up of these patients. Published cases of T1DM related to PD-1 inhibitor therapy were identified using PubMed. Eighty-three identified publications were reviewed, of which 37 publications involving 42 cases of anti-PD-1 therapy-induced T1DM were identified. The average age of patients at presentation was 62 years and 59.5% were male. The mean number of PD-1 inhibitor doses received was 5, with a mean time to presentation of 11 weeks. Initial presentation of diabetic ketoacidosis was reported in 69% of cases, with an average blood glucose of 660 mg/dL and an average HbA_1c of 8.7%. The exact mechanism PD-1 inhibitor therapy-induced T1DM is unknown. Blood glucose monitoring is recommended for all patients receiving anti-PD-1 therapy. Further research is needed to delineate the frequency of this adverse effect, as well as to evaluate potential risk factors and ideal management strategies.

Acral vascular necrosis associated with immune-check point inhibitors: case report with literature review

Background

Treatment of solid malignancies has been revolutionized with the introduction of immune checkpoint inhibitors (ICIs) and their use is being expanded in therapy of different cancers. However, immune related adverse events (IRAEs) can occur during treatment. These side effects occur due to stimulation of the innate and adaptive immune system and can lead to serious complications. Recently, acral ischemia has been reported in some cases during treatment with programmed death-1 (PD-1) and cytotoxic T lymphocyte associated antigen-4 (CTLA-4) inhibitors. Here, we discuss a case in which acral necrosis developed after initiation of a PD-1 inhibitor. We offer a review of the existing literature on the pathophysiology, clinical course and treatment outcomes.

Case presentation

A 68-year-old female was diagnosed with stage IV non-small cell lung adenocarcinoma and was started on pembrolizumab. The patient developed sudden onset numbness and discoloration of fingertips bilaterally at week 25 after initiation of ICI treatment. Extensive workup to rule out hypercoagulable, autoimmune and vascular disease was unremarkable except for mild elevation of ANA and ESR. The symptoms quickly progressed into dry gangrene within four weeks and did not respond to medical or surgical treatment. Pembrolizumab was subsequently discontinued due to progression of metastatic disease. The patient refused further interventions and transitioned to hospice care where she expired after two months.

Conclusion

Acral ischemia can develop during treatment of malignancies. This complication, although uncommon, canresult in digital amputation. Physicians should be aware of the possible progression of acral vascular necrosis when Raynaud’s like symptoms develop. Larger studies are needed to confirm the role of ICIs in the pathogenesis of acral vascular necrosis.

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.

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.

Anti-PD-1 pembrolizumab induced autoimmune diabetes in Chinese patient: A case report

RATIONALE

Programmed cell death-1 protein (PD-1) antibody is an immune-checkpoint inhibitor that triggers anti-tumor response by enhancing immune response. Although PD-1 antibody has been reported effective in some malignant tumor, it can also induce significant immune-related adverse events (irAEs) such as autoimmune diabetes.

PATIENT CONCERNS

A 67-year-old male patient with non-small cell lung cancer (NSCLS) presented with polydipsia, polyuria, weakness, and weight loss after use of anti-programmed cell death-1 antibody therapy. Hyperglycemia, high serum ketone, low bicarbonate and high anion gap were compatible with the criteria of diabetic ketoacidosis (DKA).

DIAGNOSES

Autoimmune diabetes and diabetic ketoacidosis (DKA). The presence of low serum titers of c-peptide, high blood glucose together with diabetic ketoacidosis (DKA) that occurs shortly after the use of pembrolizumab strongly supported the diagnosis of anti-PD-1 induced autoimmune diabetes.

INTERVENTIONS

The patient stopped using pembrolizumab while continuous subcutaneous insulin infusion (CSII) was started at the same time. The insulin infusion was switched to multiple daily injection (MDI) after he was discharged from hospital.

OUTCOMES

The patient is now a well-controlled insulin-dependent patient with palliative care of NSCLS.

LESSONS

Autoimmune diabetes induced by anti-programmed cell death-1 (PD-1)/programmed cell death 1 ligand 1 (PD-L1) therapy is a rare, but life threatening immune-related side effect. Physicians should closely monitor diabetes-related indexes of patients who have been undergoing the treatment of anti-PD-1/PD-L1 therapy.

Programmed Cell Death-1 Inhibitor-Induced Type 1 Diabetes Mellitus

CONTEXT

Pembrolizumab (Keytruda; Merck Sharp & Dohme) is a humanized IgG4 monoclonal antibody used in cancer immunotherapy. It targets the programmed cell death-1 (PD-1) receptor, which is important in maintaining self-tolerance. However, immune checkpoint blockade is associated with a risk for immune-related adverse events (irAEs) potentially affecting the endocrine organs. Type 1 diabetes mellitus is a rare irAE of PD-1 inhibitors, occurring in 0.2% of cases.

EVIDENCE ACQUISITION

Systematic search of four databases (MEDLINE, Embase, Web of Science, and Cochrane Library) using the search terms "diabetes" or "ketoacidosis" and "pembrolizumab," "nivolumab," "PD-1 inhibitor," or "immunotherapy." Included were articles published in English between 1 January 2012 and 1 January 2018. The search was supplemented by bibliographic searches of the complete reference lists of all included papers.

EVIDENCE SYNTHESIS

We provide an overview of all published cases (n = 42) of PD-1 inhibitor-induced type 1 diabetes mellitus to date, including a well-characterized case of islet cell antibody and glutamic acid decarboxylase antibody-positive diabetes mellitus, in a patient with a diabetes-prone HLA genotype. She presented with diabetic ketoacidosis during pembrolizumab therapy for a metastatic uveal melanoma. Furthermore, we discuss potential pathogenic mechanisms, clinical presentation, prognostic markers (β-cell antibodies and HLA type), treatment, and a screening protocol.

CONCLUSIONS

Because the use of immunotherapy will increase, it is essential that all clinicians are aware of diabetic ketoacidosis as a rare and life-threatening side effect of immunotherapy. Blood glucose monitoring during anti-PD-1 therapy is necessary.

Diabetes associated with immune checkpoint inhibition: presentation and management challenges

BACKGROUND

In recent years, immune checkpoint blockade has become a standard therapy for a wide range of cancers. Adverse events including endocrinopathies result from the induction of autoimmunity.

CASE REPORT

We report a case series of nine individuals who presented with immunotherapy-induced type 1 diabetes between 2015-2017.

DISCUSSION

Onset of diabetes occurred within 12 weeks of commencing therapy. Anti- GAD antibodies were present in six people. Retrospective testing of islet antibodies in pre-treatment samples was possible in two people and this revealed anti-GAD seroconversion in the first and high anti-GAD titres pre and post-treatment in the second person. Six people had high risk HLA haplotypes. Clinical and genetic factors are described and compared with previously published cases. This article is protected by copyright. All rights reserved.