Clinical Characteristics, Management, and Potential Biomarkers of Endocrine Dysfunction Induced by Immune Checkpoint Inhibitors

Combined use of tyrosine kinase inhibitors with PD-(L)1 blockade increased the risk of thyroid dysfunction in PD-(L)1 blockade: a prospective study

BACKGROUND

Anti-programmed cell death-1 (ligand-1) antibody [PD-(L)1-Ab] can cause destructive thyroiditis and/or hypothyroidism. In addition, tyrosine kinase inhibitors (TKIs) frequently induce hypothyroidism. The aim of this prospective study is to examine the incidence and clinical characteristics of thyroid dysfunction induced by combination therapy of a PD-(L)1-Ab and TKI [PD-(L)1-Ab/TKI].

METHODS

A total of 757 patients treated with PD-(L)1-Ab or PD-(L)1-Ab/TKI were evaluated for anti-thyroid antibodies (ATAs) at baseline and for thyroid function for 48 weeks after treatment initiation and then observed until the last visit.

RESULTS

The cumulative incidences of destructive thyroiditis [4/23 (17.4%) vs. 45/734 (6.1%) patients, p < 0.001], isolated hypothyroidism [10/23 (43.5%) vs. 29/734 (4.0%) patients, p < 0.001], and all thyroid dysfunction [14/23 (60.9%) vs. 74/734 (10.1%) patients, p < 0.001] were significantly higher in the PD-(L)1-Ab/TKI group than PD-(L)1-Ab group, respectively. All patients positive for ATAs at baseline developed thyroid dysfunction after PD-(L)1-Ab/TKI treatment, a significantly higher incidence than that in those negative for ATAs at baseline [4/4 (100%) vs. 10/19 (52.6%) patients, p = 0.026].

CONCLUSIONS

The addition of TKIs increased the risk of thyroid dysfunction induced by PD-(L)1-Ab, with the risk being higher in patients positive for baseline ATAs.

Endocrinopathies Associated With Immune Checkpoint Inhibitor Use

OBJECTIVE

To provide a clinical approach towards immune checkpoint inhibitor (ICI)-associated endocrinopathies, their link with cancer outcomes, factors which differentiate them from other immune related adverse events, and health systems innovation to improve care for these patients.

METHODS

A literature search for articles pertaining to ICIs and endocrinopathies was performed and supplemented by expert opinions of the authors.

RESULTS

While immune related adverse events can affect almost any organ, they frequently target the endocrine glands, most commonly thyroid. Different classes of ICIs have varying frequencies of endocrinopathies related to hypophysitis, thyroiditis, diabetes mellitus, and rarely hypoadrenalism and hypoparathyroidism. ICI-associated endocrinopathies share some features with classic endocrine autoimmunity but appear to be a distinct entity. They can be challenging to diagnose and manage due to nonspecific clinical features, use of exogenous glucocorticoids, and at times rapid and severe hormone deficiency. The role of anti-inflammatory high-dose glucocorticoids is minimal, and the ICI does not usually require permanent discontinuation. ICI-associated endocrinopathies usually cause permanent hormone deficiency necessitating long-term management and patient engagement. ICI-thyroiditis has been associated with improved survival, while other endocrinopathies have not shown a significant association with outcomes in cancer patients receiving ICIs. Oncoendocrinology teams can improve the care of patients with ICI-associated endocrinopathies.

CONCLUSION

This narrative review provides guidance to clinicians prescribing ICIs and those managing ICI-associated endocrinopathies, and complements the frameworks provided by major scientific societies in this field.

Changes in TgAb and TPOAb titers are greater in thyrotoxicosis than isolated hypothyroidism induced by PD-1 blockade

Anti-thyroglobulin antibodies (TgAb) and/or anti-thyroid peroxidase antibodies (TPOAb) positivity at baseline is a risk marker for thyroid immune-related adverse events (thyroid-irAEs) in anti-programmed cell death-1 antibody (PD-1-Ab) treatment; however, it is unknown if TgAb and TPOAb titers are associated with clinical characteristics of thyroid-irAEs. Among 586 patients treated with PD-1-Ab at Nagoya University Hospital between 2 November 2015 and 30 September 2021, 57 patients developed thyroid-irAEs (thyrotoxicosis [n = 38]; hypothyroidism without prior thyrotoxicosis {isolated hypothyroidism} [n = 19]) in whom thyroid function, and TgAb and TPOAb titers were determined at baseline and at the onset. The changes in TgAb (median, 54.8 vs. 0.2 IU/mL; p = 0.002) and TPOAb titers (31.6 vs. 0 IU/mL; p = 0.032) from baseline to onset of developing thyroid-irAEs were greater in patients with thyrotoxicosis than patients with isolated hypothyroidism. Higher TgAb and TPOAb titers, and the TgAb titer at baseline were associated with an earlier onset of thyrotoxicosis and higher peak free thyroxine levels, respectively. Twenty-eight patients who developed hypothyroidism after thyrotoxicosis had higher TgAb (54.5 vs. 10.7 IU/mL; p = 0.011) and TPOAb titers at baseline (46.1 vs. 9.0 IU/mL; p < 0.001) and greater changes in TgAb (61.7 vs. 7.8 IU/mL; p = 0.025) and TPOAb titers (52.8 vs. -0.8 IU/mL; p < 0.001) than patients who did not develop hypothyroidism. The TgAb titer at baseline and changes in the TgAb and TPOAb titers were greater in patients with thyrotoxicosis than patients with isolated hypothyroidism, suggesting that the magnitude of the thyroid autoimmune response reflects the clinical types of thyroid-irAEs.

Adrenal Insufficiency and Thyrotoxicosis Following Combined Immune Checkpoint Inhibitor Use: A Case Report and Literature Review

Destructive thyroiditis and secondary adrenal insufficiency are major endocrinological immune-related adverse events of immune checkpoint inhibitors (ICIs). However, the timing at which each event occurs most frequently after drug administration varies, and cases where multiple events occur simultaneously are rare. We encountered a patient who concurrently suffered from thyrotoxicosis and adrenal insufficiency. An 80-year-old woman with a history of type 2 diabetes mellitus (DM) was diagnosed with stage IVA squamous cell carcinoma of the lungs. Treatment with a combination of nivolumab and ipilimumab was initiated. Although she tested positive for thyroglobulin antibody and transient subclinical hyperthyroidism was observed after two courses, treatment with ICIs was continued. Four months later, treatment was discontinued due to drug-induced lung disease. One month after the last administration, the patient became unconscious and was admitted to another hospital, diagnosed with diabetic ketoacidosis, urinary tract infection, and sepsis. After acute-phase treatment, she was transferred to our hospital due to persistent fever and tachycardia. Thyrotoxicosis and adrenal insufficiency were observed, with high levels of free thyroxine, low thyroid-stimulating hormone (TSH), and cortisol levels. Treatment with extracellular fluids, potassium iodide, beta-blockers, and hydrocortisone was initiated, and the patient's condition improved. No other pituitary hormone deficiencies were observed. She was diagnosed with painless thyroiditis and secondary adrenal insufficiency based on the positive thyroglobulin antibody, negative TSH receptor antibody, decreased Doppler flow in thyroid ultrasonography, low adrenocorticotrophic hormone (ACTH), and low response of ACTH and cortisol to corticotropin-releasing hormone loading test. MRI revealed no abnormalities. We report a case of thyrotoxicosis and secondary adrenal insufficiency five months after the first administration of nivolumab and ipilimumab. Careful follow-up and early detection of endocrine disorders are critical in patients treated with a combination of ICIs.

Immune-related thyroid dysfunction in patients with non-small cell lung cancer

Background

Immune-related thyroid dysfunction (irTD) is a common immune-related adverse event (irAE). The potential biomarkers of irTDs and their impact on the clinical outcomes of patients with non-small cell lung cancer (NSCLC) treated with immune checkpoint inhibitors (ICIs) remain unclear. We aimed to identify potential biomarkers of irTDs and reveal the association between irTDs and the clinical outcomes in patients with NSCLC treated with ICIs.

Methods

We conducted a retrospective study on 126 patients with NSCLC, who were treated with pembrolizumab, sintilimab, atezolizumab, or camrelizumab, as first-line therapy, at the First Affiliated Hospital, College of Medicine, Zhejiang University, between July 2019 and February 2023. Anti-thyroid antibodies (ATAs), thyroid peroxidase antibody (TPOAb), thyroglobulin antibody (TGAb), serum interleukin-6 (IL-6), thyroid ultrasonography, overall survival (OS), and progression-free survival (PFS) were the main indicators.

Results

Most (92.9%) irTD cases occurred no later than one year after ICIs initiation. Patients with irTDs had higher positive rates for ATAs and TPOAb [33.3% vs. 1.3%, and 30.3% vs. 1.3%, both P<0.01, odds ratio (OR) =39.81, and OR =35.46, respectively]. Irregular echo pattern and diffuse changes were more common in patients with irTDs (70.7% vs. 47.2%, and 19.5% vs. 1.4%, P<0.05 and P<0.01, OR =2.70, and OR =17.21, respectively). OS and PFS were similar in patients with and without irTDs (P>0.05).

Conclusions

The ATAs, TPOAb, and abnormal thyroid ultrasonographic findings (irregular echo patterns and diffuse changes) are potential biomarkers of irTDs. Patients with NSCLC treated with ICIs (pembrolizumab, sintilimab, atezolizumab, and camrelizumab) who developed irTDs had no advantage in terms of clinical outcomes compared to euthyroid patients.

Life-Threatening Endocrinological Immune-Related Adverse Events of Immune Checkpoint Inhibitor Therapy

Malignant neoplasms are currently one of the leading causes of morbidity and mortality worldwide, posing a major public health challenge. However, recent advances in research in cancer biology and immunity have led to the development of immunotherapy, which is now used on an everyday basis in cancer treatment in addition to surgical treatment, classical cytostatics, and radiotherapy. The efficacy of immunotherapy has promoted the great popularity of this treatment among patients, as well as significant research interest. The increasing number of patients being treated with immunotherapy not only reassures physicians of the efficacy of this technique but also shows the wide spectrum of side effects of this therapy, which has not been considered before. Immune-related adverse events may affect many systems and organs, such as digestive, cardiovascular, respiratory, skin, or endocrine organs. Most complications have a mild or moderate course, but there are life-threatening manifestations that are essential to be aware of because if they are not properly diagnosed and treated on time, they can have fatal consequences. The purpose of this paper was to present the results of a literature review on the current state of knowledge on life-threatening endocrine side effects (such as adrenal crisis, thyroid storm, myxoedema crisis, diabetic ketoacidosis, and severe hypocalcaemia) of immune checkpoint inhibitors to provide information on symptoms, diagnostics, and management strategies.

Severe thyrotoxicosis induced by tislelizumab: a case report and literature review

Immune checkpoint inhibitors (ICIs) have made significant breakthroughs in the treatment of a variety of malignancies. As its use increases, the unique immune-mediated toxicity profile of ICls are becoming apparent. We report a case of immune-related endocrine adverse events (irAE) in a patient with hepatocellular carcinoma treated with anti-programmed cell death protein 1 (PD-1) (tislelizumab). Although many irAEs have been reported, few cases of severe thyrotoxicosis have been described after immunotherapy in the literature. We present the case of a 49-year-old male who experienced a Grade 3 tislelizumab-related adverse reaction according to Common Terminology Criteria for Adverse Events (CTCAE5.0) and received methylprednisolone, thiamazole, and levothyroxine sodium tablets. Early identification of irAEs, risk factors, regular monitoring, use of steroids and/or immunoglobulins, and adjuvant supportive care are critical to the clinical prognosis of patients. It should be underlined that the tumor benefits of ICI therapy outweigh the risks associated with ICI-induced endocrine disorders, and ICI treatment should not be stopped or delayed except in rare cases (adrenal crisis, severe thyrotoxicosis). The familiarity of healthcare professionals with irAEs of the thyroid when thyrotoxicosis occurs is important to facilitate an effective diagnosis and appropriate treatment of this increasingly common thyroid disorder.

Risk of Thyroid Dysfunction in PD-1 Blockade Is Stratified by the Pattern of TgAb and TPOAb Positivity at Baseline

CONTEXT

Positive antithyroglobulin (TgAb) and/or antithyroid peroxidase antibodies (TPOAb) at baseline indicate a high risk of thyroid immune-related adverse events (irAEs) induced by antiprogrammed cell death-1 antibodies (anti-PD-1-Ab). However, whether the positivity patterns of both antibodies are associated with the risk of thyroid irAEs is unknown.

OBJECTIVE

The aim of the present study was to clarify the association of the pattern of TgAb and TPOAb positivity at baseline with the risk of thyroid irAEs induced by anti-PD-1-Ab.

METHODS

Patients (n = 516) were evaluated for TgAb and TPOAb at baseline and prospectively for thyroid function every 6 weeks for 24 weeks after initiating anti-PD-1-Ab.

RESULTS

Fifty-one (9.9%) patients developed thyroid irAEs (thyrotoxicosis in 34, hypothyroidism without prior thyrotoxicosis in 17). Twenty-five patients subsequently developed hypothyroidism following thyrotoxicosis. The cumulative incidence of thyroid irAEs differed among 4 groups classified by the presence of TgAb/TPOAb at baseline (group 1: TgAb-(-)/TPOAb-(-), 4.6% [19/415]; group 2: TgAb-(-)/TPOAb-(+), 15.8% [9/57]; group 3: TgAb-(+)/TPOAb-(-), 42.1% [8/19]; group 4: TgAb-(+)/TPOAb-(+), 60.0% [15/25]) as follows: groups 1 vs 2-4 (P ≤ .001) and groups 2 vs 3 (P = .008) and 4 (P < .001). There were different incidences of thyrotoxicosis (groups 1-4, 3.1%, 5.3%, 31.6%, 48.0%, respectively; P < .001) in groups 1 vs 3 and 4, and groups 2 vs 3 and 4, and of hypothyroidism (groups 1-4: 2.9%, 15.8%, 31.6%, 60.0%, respectively; P < .001) in groups 1 vs 2 to 4, and groups 2 vs 4.

CONCLUSION

The risk of thyroid irAEs was affected by the pattern of TgAb and TPOAb positivity at baseline; there were high risks of thyrotoxicosis in patients with TgAb-(+) and of hypothyroidism in patients with TgAb-(+) and those with TPOAb-(+).

Preconditioning of the immune system modulates the response of papillary thyroid cancer to immune checkpoint inhibitors

BACKGROUND

The response of solid tumors such as papillary thyroid cancer (PTC) to immune checkpoint inhibitors (ICIs) is highly variable. The biological basis of this variability remains unknown.

METHODS

To test the hypothesis that preconditioning of the immune system modulates the therapeutic effect of ICIs, we used a murine model where PTC and iodine exacerbated thyroiditis (IET) can be induced in a temporally predictable fashion. A total of 122 mice were divided into 3 experimental groups. In the first one, named concomitant IET and PTC (No.=40), IET, and PTC were induced at the same time; in the second one, named pre-existing IET (No.=44), IET was induced prior to the induction of PTC; in the third one, named no IET (No.=38), only PTC was induced. Following disease induction, mice of each group were treated with anti-PD-1 antibody, anti-lymphocyte activation gene 3 antibody (anti-Lag3), anti-T-cell immunoglobulin and mucin domain 3 antibody (anti-Tim3), or IgG control. Ten weeks after the initial ICI injection, mice were sacrificed to collect the thyroid gland for histological analysis, to quantify the incidence and burden of PTC, and to perform high-throughput single-cell RNA sequencing of infiltrating CD45⁺ cells.

RESULTS

In the concomitant IET and PTC group, ICI treatment reduced PTC incidence (p=0.002 comparing treatment with any ICI vs control), while it had no effect in the pre-existing IET and no IET groups. Single-cell sequencing of thyroidal CD45⁺ cells showed that the different ICIs tested had both specific and shared effects on all the components of the thyroidal immune cell infiltrate. The shared effect of the tested ICIs was dependent on the presence of pre-existing versus concomitant IET. In the context of concomitant IET, ICI treatment resulted in the modulation of a greater number of pathways related to both innate and adaptive immunity.

CONCLUSIONS

Response to ICIs depends on the status of the immune system of the treated individual. Modulation of the immune system should be explored as a tool to improve response to ICIs in patients with PTC or other forms of cancer.

Recovery from insulin dependence in immune checkpoint inhibitor-associated diabetes mellitus: A case report

Immune checkpoint inhibitor-associated diabetes mellitus (ICI-DM) is a rare immune-related adverse event and is usually considered permanent. Here, we report the first case of a 54-year-old man with ICI-DM who recovered from insulin dependence. He was diagnosed with lung cancer and started pembrolizumab therapy. After seven cycles, he developed ICI-associated secondary adrenal insufficiency and started hydrocortisone supplementation. Subsequently, he complained of fatigue, and blood examinations showed hyperglycemia with ketosis. A glucagon challenge test indicated insulin dependence. He was diagnosed with ICI-DM and insulin therapy was initiated. Pembrolizumab therapy was discontinued due to concomitant ICI-associated hepatitis. Six months later, a glucagon challenge test result showed an improvement in insulin secretion, and insulin therapy was discontinued. The lung cancer lesions continued to shrink. Even if ICI-DM develops, it might be possible to control the underlying cancer while avoiding lifelong insulin therapy through early discontinuation of ICI.

Elevated TSH Level, TgAb, and Prior Use of Ramucirumab or TKIs as Risk Factors for Thyroid Dysfunction in PD-L1 Blockade

BACKGROUND

Thyroid dysfunction is frequently caused by treatment with antiprogrammed cell death-1 ligand 1 antibodies (PD-L1-Abs) and anticancer drugs, including ramucirumab (RAM) and multitargeted tyrosine kinase inhibitors (multi-TKIs), which are often used prior to PD-L1-Ab treatment in cancer patients.

METHODS

A total of 148 patients treated with PD-L1-Abs were evaluated for antithyroid antibodies at baseline and for thyroid function every 6 weeks for 24 weeks after treatment initiation and then were observed until the visits stopped.

RESULTS

Of the 148 patients, 15 (10.1%) developed thyroid dysfunction after PD-L1-Ab treatment (destructive thyroiditis in 8 and hypothyroidism without preceding thyrotoxicosis in 7). The prevalence of an elevated thyroid-stimulating hormone (TSH) level at baseline (3/15 [20.0%] vs 4/133 [3.0%], P < .05), positive antithyroglobulin antibodies (TgAbs) at baseline (4/15 [26.7%] vs 5/133 [3.8%], P < .05) and prior treatment with RAM or multi-TKIs (3/15 [20.0%] vs 5/133 [3.8%], P < .05) were significantly higher in patients with vs without thyroid dysfunction. In a multivariate analysis, elevated TSH level at baseline, TgAb positivity at baseline, and prior treatment with RAM or multi-TKIs were significantly associated with the development of thyroid dysfunction, with ORs of 7.098 (95% CI 1.154-43.638), 11.927 (95% CI 2.526-56.316), and 8.476 (95% CI 1.592-45.115), respectively.

CONCLUSION

The results of this real-world study suggest that the risk of thyroid dysfunction induced by PD-L1-Abs can be predicted by the TSH level at baseline, TgAb positivity at baseline, and prior treatment with RAM or multi-TKIs.

[Pituitary immune-related adverse events induced by programmed cell death protein 1 inhibitors in advanced lung cancer patients: A report of 3 cases]

Pituitary immune-related adverse events induced by programmed cell death protein 1 inhibitors in advanced lung cancer patients: A report of 3 cases SUMMARY Programmed cell death protein 1 (PD-1) and its ligand 1 (PD-L1) have been widely used in lung cancer treatment, but their immune-related adverse events (irAEs) require intensive attention. Pituitary irAEs, including hypophysitis and hypopituitarism, are commonly induced by cytotoxic T lymphocyte antigen 4 inhibitors, but rarely by PD-1/PD-L1 inhibitors. Isolated adrenocorticotropic hormone(ACTH) deficiency (IAD) is a special subtype of pituitary irAEs, without any other pituitary hormone dysfunction, and with no enlargement of pituitary gland, either. Here, we described three patients with advanced lung cancer who developed IAD and other irAEs, after PD-1 inhibitor treatment. Case 1 was a 68-year-old male diagnosed with metastatic lung adenocarcinoma with high expression of PD-L1. He was treated with pembrolizumab monotherapy, and developed immune-related hepatitis, which was cured by high-dose methylprednisolone [0.5-1.0 mg/(kg·d)]. Eleven months later, the patient was diagnosed with primary gastric adenocarcinoma, and was treated with apatinib, in addition to pembrolizumab. After 17 doses of pembrolizumab, he developed severe nausea and asthenia, when methylprednisolone had been stopped for 10 months. His blood tests showed severe hyponatremia (121 mmol/L, reference 137-147 mmol/L, the same below), low levels of 8:00 a.m. cortisol (< 1 μg/dL, reference 5-25 μg/dL, the same below) and ACTH (2.2 ng/L, reference 7.2-63.3 ng/L, the same below), and normal thyroid function, sex hormone and prolactin. Meanwhile, both his lung cancer and gastric cancer remained under good control. Case 2 was a 66-year-old male with metastatic lung adenocarcinoma, who was treated with a new PD-1 inhibitor, HX008, combined with chemotherapy (clinical trial number: CTR20202387). After 5 months of treatment (7 doses in total), his cancer exhibited partial response, but his nausea and vomiting suddenly exacerbated, with mild dyspnea and weakness in his lower limbs. His blood tests showed mild hyponatremia (135 mmol/L), low levels of 8:00 a.m. cortisol (4.3 μg/dL) and ACTH (1.5 ng/L), and normal thyroid function. His thoracic computed tomography revealed moderate immune-related pneumonitis simultaneously. Case 3 was a 63-year-old male with locally advanced squamous cell carcinoma. He was treated with first-line sintilimab combined with chemotherapy, which resulted in partial response, with mild immune-related rash. His cancer progressed after 5 cycles of treatment, and sintilimab was discontinued. Six months later, he developed asymptomatic hypoadrenocorticism, with low level of cortisol (1.5 μg/dL) at 8:00 a.m. and unresponsive ACTH (8.0 ng/L). After being rechallenged with another PD-1 inhibitor, teslelizumab, combined with chemotherapy, he had pulmonary infection, persistent low-grade fever, moderate asthenia, and severe hyponatremia (116 mmol/L). Meanwhile, his blood levels of 8:00 a.m. cortisol and ACTH were 3.1 μg/dL and 7.2 ng/L, respectively, with normal thyroid function, sex hormone and prolactin. All of the three patients had no headache or visual disturbance. Their pituitary magnetic resonance image showed no pituitary enlargement or stalk thickening, and no dynamic changes. They were all on hormone replacement therapy (HRT) with prednisone (2.5-5.0 mg/d), and resumed the PD-1 inhibitor treatment when symptoms relieved. In particular, Case 2 started with high-dose prednisone [1 mg/(kg·d)] because of simultaneous immune-related pneumonitis, and then tapered it to the HRT dose. His cortisol and ACTH levels returned to and stayed normal. However, the other two patients' hypopituitarism did not recover. In summary, these cases demonstrated that the pituitary irAEs induced by PD-1 inhibitors could present as IAD, with a large time span of onset, non-specific clinical presentation, and different recovery patterns. Clinicians should monitor patients' pituitary hormone regularly, during and at least 6 months after PD-1 inhibitor treatment, especially in patients with good oncological response to the treatment.

Increased Risk of Thyroid Dysfunction by PD-1 and CTLA-4 Blockade in Patients Without Thyroid Autoantibodies at Baseline

BACKGROUND

Previous studies showed that although the risk of thyroid dysfunction [thyroid immune-related adverse events (irAEs)] induced by anti-programmed cell death-1 antibodies (PD-1-Ab) was as low as 2% to 7% in patients negative for anti-thyroid antibodies (ATAs) at baseline, it was much higher (30%-50%) in patients positive for ATAs. However, whether a similar increase occurs with combination therapy using PD-1-Ab plus anti-cytotoxic T-lymphocyte antigen-4 antibody (CTLA-4-Ab) is unknown.

METHODS

A total of 451 patients with malignancies treated with PD-1-Ab, CTLA-4-Ab, or a combination of PD-1-Ab and CTLA-4-Ab (PD-1/CTLA-4-Abs) were evaluated for ATAs at baseline and for thyroid function every 6 weeks for 24 weeks after treatment initiation and then observed until the last clinical visit.

RESULTS

Of the 451 patients, 51 developed thyroid irAEs after immunotherapy [41 of 416 (9.9%) treated with PD-1-Ab, 0 of 8 (0%) treated with CTLA-4-Ab, and 10 of 27 (37.0%) treated with PD-1/CTLA-4-Abs]. The cumulative incidence of thyroid irAEs was significantly higher in patients who were positive vs negative for ATAs at baseline after both PD-1-Ab [28/87 (32.2%) vs 13/329 (4.0%), P < 0.001] and PD-1/CTLA-4-Abs [6/10 (60.0%) vs 4/17 (23.5%), P < 0.05] treatments. The risk of thyroid irAEs induced by PD-1/CTLA-4Abs, which was significantly higher than that induced by PD-1-Ab, in patients negative for ATAs at baseline was not statistically different from that induced by PD-1-Ab in patients positive for ATAs at baseline.

CONCLUSIONS

This study showed that the incidence of thyroid irAEs was high and not negligible after PD-1/CTLA-4-Abs treatment even in patients negative for ATAs at baseline.

Immune Checkpoint Inhibitors as a Threat to the Hypothalamus-Pituitary Axis: A Completed Puzzle

Immune checkpoint inhibitors (ICI) prolong the survival in an increasing number of patients affected by several malignancies, but at the cost of new toxicities related to their mechanisms of action, autoimmunity. Endocrine toxicity frequently occurs in patients on ICI, but endocrine dysfunctions differ based on the ICI-subclass, as follows: agents targeting the CTLA4-receptor often induce hypophysitis and rarely thyroid dysfunction, which is the opposite for agents targeting the PD-1/PD-L1 axis. Recently, few cases of central diabetes insipidus have been reported as an adverse event induced by both ICI-subclasses, either in the context of anterior hypophysitis or as selective damage to the posterior pituitary or in the context of hypothalamitis. These new occurrences demonstrate, for the first time, that ICI-induced autoimmunity may involve any tract of the hypothalamic-pituitary axis. However, the related pathogenic mechanisms remain to be fully elucidated. Similarly, the data explaining the endocrine system susceptibility to primary and ICI-induced autoimmunity are still scarce. Since ICI clinical indications are expected to expand in the near future, ICI-induced autoimmunity to the hypothalamic-pituitary axis presents as a unique in vivo model that could help to clarify the pathogenic mechanisms underlying both the dysfunction induced by ICI to the hypothalamus-pituitary axis and primary autoimmune diseases affecting the same axis.

Biomarkers and risk factors for the early prediction of immune-related adverse events: a review

In recent years, immunotherapy has been widely used to treat patients with malignant tumors. While immune checkpoint inhibitors (ICIs) significantly improve the prognosis of cancer patients, the incidence of immune-related adverse events (irAEs) is increasing. Not only can irAEs accumulate in multiple organ systems throughout the body, but rare adverse reactions may also occur continuously. In severe cases, irAEs can be life-threatening or even lead to death. Therefore, the early identification, diagnosis and treatment of irAEs are very important. Early identification of patients with high-risk irAEs as well as the reduction or avoidance of severe irAEs have important clinical significance. This article will review the research progress of early predictive biomarkers and risk factors for the occurrence of irAEs and propose potential future directions for follow-up research and clinical applications.

Survival benefit of endocrine dysfunction following immune checkpoint inhibitors for nonthyroidal cancers

PURPOSE OF REVIEW

Our goal is to review pertinent data evaluating the association between immune checkpoint inhibitor (ICI)-induced endocrine dysfunction and survival in cancer patients as well as to understand the potential molecular links between these.

RECENT FINDINGS

ICIs have revolutionized cancer therapy but have also led to multiple immune-related adverse events (irAEs). Studies have demonstrated a link between the development of irAEs and improved survival, suggesting that ICI-induced antitumor immunity and autoimmunity are coupled. Thyroid irAEs are most frequently and strongly associated with improved survival, particularly in the context of overt thyroid dysfunction. Other endocrine irAEs, such as hypophysitis and diabetes are quite rare wherein the treatment approach or the disease process itself may mitigate improvement in survival. Preclinical and translational data indicate a role for CD4+ T cells, regulatory T cells and/or cytokines mediating irAEs, including thyroiditis.

SUMMARY

The development of irAEs is associated with improved tumor responses and survival in cancer patients. Thyroid irAEs, alone or in combination with other irAEs, are most strongly associated with improved outcomes. Biomarkers of response to ICIs are lacking, despite well-characterized pathologic and genomic susceptibilities predicting ICI efficacy. Early detection of thyroid irAEs may identify patients most likely to have durable antitumor response to ICIs. Although irAEs and antitumor immunity appear 'coupled', translational studies indicate the potential for their 'uncoupling', which could enable antitumor efficacy with greater safety margins.