Hyperglycaemia following immune checkpoint inhibitor therapy-Incidence, aetiology and assessment

AIMS

We systematically studied the presence of hyperglycaemia during treatment with Immune Checkpoint Inhibitors (ICPI) for cancer, in those with and without diabetes at baseline, and determined the cause of new-onset hyperglycaemia, METHODS: Retrospective review of electronic records of those receiving an ICPI for melanoma, lung or renal cancer.

RESULTS

Overall, 959 participants were included. In this study, 103 had diabetes at baseline (10.7%). Those with lung cancer had the highest frequency of diabetes; 131 people had hyperglycaemia (defined as at least one glucose ≥11.1 mmol/L) in the year after starting an ICPI. The incidence was 55% in those with diabetes at baseline, and 8.6% in those without baseline diabetes. Among 74 with new-onset hyperglycaemia (without pre-existing diabetes) 76% was attributable to steroid induced diabetes, with 9.5% due to ICPI Induced diabetes resembling type 1 diabetes.

CONCLUSIONS

Hyperglycaemia is common in persons receiving an ICPI for cancer, including 8.6% of those without known diabetes. While much of this is due to glucocorticoid use, care is needed to avoid missing those with ICPI-induced diabetes who are at risk of diabetic ketoacidosis, which is a medical emergency.

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.

Thyroid abnormalities following the use of cytotoxic T-lymphocyte antigen-4 and programmed death receptor protein-1 inhibitors in the treatment of melanoma

CONTEXT

Checkpoint inhibitors are emerging as important cancer therapies but are associated with a high rate of immune side effects, including endocrinopathy.

OBJECTIVE

To determine the burden of thyroid dysfunction in patients with melanoma treated with immune checkpoint inhibitors and describe the clinical course.

DESIGN AND PATIENTS

Consecutive patients with melanoma treated with either ipilimumab, nivolumab, pembrolizumab or the combination of ipilimumab and nivolumab were identified. Baseline thyroid function tests were used to exclude those with pre-existing thyroid abnormalities, and thyroid function tests during treatment used to identify those with thyroid dysfunction.

RESULTS

Rates of overt thyroid dysfunction were in keeping with the published phase 3 trials. Hypothyroidism occurred in 13·0% treated with a programmed death receptor-1 (PD-1) inhibitor and 22·2% with a combination of PD-1 inhibitor and ipilimumab. Transient subclinical hyperthyroidism was observed in 13·0% treated with a PD-1 inhibitor, 15·9% following a PD-1 inhibitor, and 22·2% following combination treatment with investigations suggesting a thyroiditic mechanism rather than Graves' disease, and a high frequency of subsequent hypothyroidism. Any thyroid abnormality occurred in 23·0% following ipilimumab, 39·1% following a PD-1 inhibitor and 50% following combination treatment. Abnormal thyroid function was more common in female patients.

CONCLUSION

Thyroid dysfunction occurs commonly in patients with melanoma treated with immune checkpoint inhibitors, with rates, including subclinical dysfunction, occurring in up to 50%.

Prevalence of diabetes in patients admitted to a cancer hospital

Cancer rates are increased in people with diabetes. There is also recent evidence that outcomes from cancer treatment are worse in those with diabetes. There is a need to assess the prevalence of diabetes in cancer patients in order to tailor resources and improve clinical outcomes. This study examined the prevalence of diabetes and hyperglycaemia and specific referrals amongst hospitalised patients in a specialist cancer hospital.

In a cancer hospital 11% of in-patients had either identified diabetes or hyperglycaemia (random blood glucose >11mmol/l.) Consecutive referrals to a diabetes consultant confirmed that over half of patients had gastro-intestinal tract primary cancers, over 20% had poor glycaemic control whilst on steroids, and 18% had poor glycaemic control during artificial nutrition. Referrals came from both medical and surgical teams.

Thus diabetes and hyperglycaemia are common problems amongst in-patients with cancer, and these patients have complex diabetes requirement. Patients with cancer and diabetes need access to specialist diabetes care.

Human fetal mesenchymal stem cells differentiate into brown and white adipocytes: a role for ERRalpha in human UCP1 expression

We investigated the ability of fetal mesenchymal stem cells (fMSCs) to differentiate into brown and white adipocytes and compared the expression of a number of marker genes and key regulatory factors. We showed that the expression of key adipocyte regulators and markers during differentiation is similar to that in other human and murine adipocyte models, including induction of PPARgamma2 and FABP4. Notably, we found that the preadipocyte marker, Pref-1, is induced early in differentiation and then declines markedly as the process continues, suggesting that fMSCs first acquire preadipocyte characteristics as they commit to the adipogenic lineage, prior to their differentiation into mature adipocytes. After adipogenic induction, some stem cell isolates differentiated into cells resembling brown adipocytes and others into white adipocytes. Detailed investigation of one isolate showed that the novel brown fat-determining factor PRDM16 is expressed both before and after differentiation. Importantly, these cells exhibited elevated basal UCP-1 expression, which was dependent on the activity of the orphan nuclear receptor ERRalpha, highlighting a novel role for ERRalpha in human brown fat. Thus fMSCs represent a useful in vitro model for human adipogenesis, and provide opportunities to study the stages prior to commitment to the adipocyte lineage. They also offer invaluable insights into the characteristics of human brown fat.

Conditionally immortalized white preadipocytes: a novel adipocyte model

This study describes a novel approach to generate conditionally immortalized preadipocyte cell lines from white adipose tissue (IMWAT) that can be induced to differentiate into white adipocytes even after expansion in culture. Such adipocytes express markers of white fat such as peroxisome proliferator-activated receptor gamma and aP2 but not brown fat markers, have an intact insulin signaling pathway, and express proinflammatory cytokines. They can be readily transduced with adenoviral vectors, allowing them to be used to investigate the consequences of the depletion of specific adipocyte factors using short hairpin RNA. This approach has been used to study the effect of reduced expression of the nuclear receptor corepressor receptor interacting protein 140 (RIP140), a regulator of adipocyte function. The depletion of RIP140 results in changes in metabolic gene expression that resemble those in adipose tissue of the RIP140 null mouse. Thus, IMWAT cells provide a novel model for adipocytes that are derived from preadipocytes rather than fibroblasts and provide an alternative system to primary preadipocytes for the investigation of adipocyte function.

Isolated B-cell lymphoma of the pituitary region: a rare clinical entity

Metastatic carcinoma in the pituitary region is a well-recognized clinical entity (Teears and Silverman, 1975), and lymphomatous involvement as part of systemic disease is well documented (Mathiasen et al, 2000). This article describes the unusual case of a B-cell lymphoma localized to the pituitary region without systemic involvement.