Seasonal AMH variability implies a positive effect of UV exposure on the deterioration of ovarian follicles.

Anti-Müllerian hormone (AMH) is produced exclusively by granulosa cells of ovarian follicles and is an indicator of ovarian reserve which declines with age. Seasonality in AMH levels have been reported to be correlated with variations in Vitamin D levels, which is dependent on sunlight exposure. However, the effects of age and its association with solar radiation intensity with respect to AMH was never studied before. In this study, we investigated the relationship between AMH levels with season and with solar radiation intensity in a cohort of 2235 women aged 19-40 years undergoing hormonal work-up over a four-year period. Our findings revealed that among women aged 20-29 years, there was no significant association between AMH levels and either season or solar radiation intensity. However, for women aged 30-40 years, a seasonal pattern was observed, with higher AMH levels during spring and autumn months characterized by moderate solar radiation intensity. Women in their declining ovarian reserve age were found to be more sensitive to the effects of moderate solar radiation. Moderate solar radiation exposure positively impacted AMH levels, whereas low and high intensity exposure had a negative effect. Our findings indicate that age and solar radiation intensity must be considered when assessing AMH levels and provide valuable insights into the intricate relationship between AMH, seasonality, and UVB exposure in the context of reproductive health.

Isolated autoimmune adrenocorticotropic hormone deficiency: A positive predictor of survival among cancer patients treated with checkpoint inhibitors.

OBJECTIVE: We aimed to characterize cancer patients who developed isolated adrenocorticotrophic hormone (ACTH) deficiency (IAD) after treatment with checkpoint-inhibitors (CPIs), including clinical manifestations, laboratory findings and risk factors, and to evaluate the prognostic significance of this complication. DESIGN: A retrospective case-control study. METHODS: We conducted a retrospective analysis of 2225 cancer patients treated with CPIs between 2015 and 2021 in our institute. We identified a subgroup of patients with sub-normal cortisol levels due to ACTH deficiency, and comprehensively extracted all relevant data. We compared the patients survival rates using a log-rank test and a multi-variable Cox regression. RESULTS: Among 2225 patients, hypocortisolemia was documented in 99 (4.45%) patients, and 19 of them were diagnosed with IAD (0.85%). Asthenia and diarrhea were the most reported complaints (36.8%), and melanoma was the most common malignancy (68.42%) within the IAD group. In multivariable analysis, IAD was associated with better survival rates (p = .018), female gender (63.2% vs 40%, p = .041), treatment with Ipilimumab (57.9% vs. 19.4%, p < .001), and younger age (median 56 IQR 51-69, vs. median 69 IQR 60-76, p = .004). CONCLUSIONS: IAD is the dominant autoimmune etiology for cortisol deficiency among patients receiving immunotherapy and is reported for the first time as a positive predictor of survival among cancer patients treated with CPIs. In our patients, IAD development was associated with female gender, treatment with ipilimumab, and younger age.

Treating Alpelisib-Induced Hyperinsulinemia in Patients with Advanced Breast Cancer - A Real-Life Experience.

PIK3CA activating mutations are found in 40% of advanced breast cancer and are associated with worse prognosis. PI3K blockage is associated with insulin resistance, leading to hyperglycemia and hyperinsulinemia. Alpelisib is the first PI3K inhibitor used in cancer treatment. Laboratory evidence indicated that alpelisib-induced hyperinsulinemia offsets the drug's efficacy, but insulin levels were not tested in the clinical trials that evaluated alpelisib for breast cancer. Hyperglycemia could also interfere with anti-tumor effects of PI3K inhibitors by inducing Immune tolerance and altered mitochondrial metabolism. We have monitored insulin levels in 4 breast cancer patients with concomitant metabolic syndrome treated with alpelisib, and pre-treated patients with baseline increased insulin levels with pioglitazone, a potent insulin sensitizer, to target both hyperinsulinemia and hyperglycemia, and we report the treatment course of these patients. All patients achieved glycemic control and were able to maintain alpelisib dose intensity. Duration of response to alpelisib was longer than anticipated in this treatment setting. Insulin dynamics confirmed the efficacy of pioglitazone as a specific on-target hypoglycemic and hypo-insulinemic agent in the unique setting of PI3K blockade. Our experience suggests that targeting hyperinsulinemia in patients with is safe and feasible and results in good metabolic and oncologic outcomes.

Diagnostic criteria and proposed management of immune-related endocrinopathies following immune checkpoint inhibitor therapy for cancer.

Checkpoint inhibitors are now widely used in the management of many cancers. Endocrine toxicity is amongst the most common side effects. These endocrinopathies differ from most other immune-related toxicities in frequently being irreversible and rarely requiring cessation of checkpoint inhibitor therapy. This review considers an approach to the presentation and diagnosis of endocrinopathies, compared to classical endocrine diagnosis, suggesting improvements to classification and treatment based on fundamental endocrine principles. These will help to align management with other similar endocrine conditions and standardise the diagnosis and reporting of endocrine toxicity of checkpoint inhibitors to improve both endocrine and oncological care. In particular, the importance of considering any inflammatory phase (such as painful thyroiditis or hypophysitis resulting in the pituitary enlargement), from the endocrine consequences (transient hyperthyroidism followed by hypothyroidism, pan-hypopituitarism or isolated adrenocorticotrophic hormone deficiency), is highlighted. It is also important to consider the potential confounder of exogenous corticosteroids in adrenal suppression.

An Exercise-Induced Metabolic Shield in Distant Organs Blocks Cancer Progression and Metastatic Dissemination.

Exercise prevents cancer incidence and recurrence, yet the underlying mechanism behind this relationship remains mostly unknown. Here we report that exercise induces the metabolic reprogramming of internal organs that increases nutrient demand and protects against metastatic colonization by limiting nutrient availability to the tumor, generating an exercise-induced metabolic shield. Proteomic and ex vivo metabolic capacity analyses of murine internal organs revealed that exercise induces catabolic processes, glucose uptake, mitochondrial activity, and GLUT expression. Proteomic analysis of routinely active human subject plasma demonstrated increased carbohydrate utilization following exercise. Epidemiologic data from a 20-year prospective study of a large human cohort of initially cancer-free participants revealed that exercise prior to cancer initiation had a modest impact on cancer incidence in low metastatic stages but significantly reduced the likelihood of highly metastatic cancer. In three models of melanoma in mice, exercise prior to cancer injection significantly protected against metastases in distant organs. The protective effects of exercise were dependent on mTOR activity, and inhibition of the mTOR pathway with rapamycin treatment ex vivo reversed the exercise-induced metabolic shield. Under limited glucose conditions, active stroma consumed significantly more glucose at the expense of the tumor. Collectively, these data suggest a clash between the metabolic plasticity of cancer and exercise-induced metabolic reprogramming of the stroma, raising an opportunity to block metastasis by challenging the metabolic needs of the tumor. SIGNIFICANCE: Exercise protects against cancer progression and metastasis by inducing a high nutrient demand in internal organs, indicating that reducing nutrient availability to tumor cells represents a potential strategy to prevent metastasis. See related commentary by Zerhouni and Piskounova, p. 4124.

The predictive potential of autoimmune-inflammatory syndrome induced by adjuvants (ASIA) criteria to assess the risk of adverse events and efficacy of immune checkpoint inhibitor therapy.

At the moment, there are no approved predictive markers of immune adverse events (irAES) induced by immune checkpoint inhibitors (ICIs) and the treatment efficacy. The early stages of irAES have some similarities with adjuvant-induced autoimmune/pro-inflammatory syndrome (ASIA). This study aims to assess the predictive possibility of using the "ASIA questionnaire" in patients on immune checkpoint inhibitor therapy in comparison with determination of PD-L1 expression to predict the risk of irAES development and therapy efficacy. We examined patients (n = 91) being treated for solid tumors. The signs of ASIA were found in 74% (66/91), while ASIA syndrome was diagnosed in 54% of cases (49/91). No statistically significant difference in the frequency of ICI-dependent complication development regarding the presence of previous ASIA clinical manifestations, hereditary factors, sex, different trigger factors was found. Index based on combination of PD-L1 determination and ASIA index was created. With reference > 2.5 units, the disease control rate (DCR) could be predicted with sensitivity 100.0% and specificity 70.00%, p = 0.007. The study did not reveal the diagnostic value of ASIA questionnaire to assess the risk of adverse events; however, in early stages, the development of ASIA symptoms diagnosed with the questionnaire in complex with PD-L1 expression allowed to predict a treatment efficacy.

Food-seeking behavior is triggered by skin ultraviolet exposure in males.

Sexual dimorphisms are responsible for profound metabolic differences in health and behavior. Whether males and females react differently to environmental cues, such as solar ultraviolet (UV) exposure, is unknown. Here we show that solar exposure induces food-seeking behavior, food intake, and food-seeking behavior and food intake in men, but not in women, through epidemiological evidence of approximately 3,000 individuals throughout the year. In mice, UVB exposure leads to increased food-seeking behavior, food intake and weight gain, with a sexual dimorphism towards males. In both mice and human males, increased appetite is correlated with elevated levels of circulating ghrelin. Specifically, UVB irradiation leads to p53 transcriptional activation of ghrelin in skin adipocytes, while a conditional p53-knockout in mice abolishes UVB-induced ghrelin expression and food-seeking behavior. In females, estrogen interferes with the p53-chromatin interaction on the ghrelin promoter, thus blocking ghrelin and food-seeking behavior in response to UVB exposure. These results identify the skin as a major mediator of energy homeostasis and may lead to therapeutic opportunities for sex-based treatments of endocrine-related diseases.

RCC Real-World Data: Prognostic Factors and Risk Stratification in the Immunotherapy Era.

Immunotherapy has transformed the landscape of treatment in metastatic renal cell carcinoma (mRCC) in the last decade. Currently, prognostic risk stratification is based on the model developed in the era of vascular endothelial growth factor receptor inhibitors (VEGFRi) by Heng in 2009. Our study aims to find the most relevant risk criteria for mRCC patients treated with checkpoint inhibitors (CPI). In a retrospective cohort study, laboratory, pathology, demographic, and clinical data were retrieved from electronic medical records of consecutive mRCC patients treated with CPI in a tertiary center between 2015 and 2020. An unbiased multivariate analysis was performed to define predictive variables with a bootstrap validation step. We analyzed data on 127 patients with a median follow-up of 60 months. The median overall survival (OS) since the diagnosis of metastatic disease was 57 months. The response rate for CPI was 39%. Five risk factors were correlated with worse OS: intact primary kidney tumor (HR 2.33, p = 0.012), liver metastasis (HR 3.33, p = 0.001),

Sexual dysfunction among adolescent and young adult cancer patients: diagnostic and therapeutic approach.

PURPOSE OF REVIEW: We present a review for healthcare professionals, formulated by a multidisciplinary team, for screening and interventions, describing common sexual impairments encountered by adolescent and young adult cancer patients (AYACP), and suggest a comprehensive evidence-based assessment approach and interventions for treatment of sexual dysfunction (SD). RECENT FINDINGS: We discuss the various aspects of SD in AYACP, including causes, challenges and etiologies, and then go on to recommend increased awareness and guidance in healthcare workers, in order to optimize diagnosis and treatment of SD. SUMMARY: Although the extent of SD among AYACP is widely recognized, oncological clinicians rarely address SD in their routine practice, lacking a clear approach of interdisciplinary diagnostic and therapeutic interventions. Here, we suggest guiding clinical management to optimize treatment quality.

Management Strategies for Hyperglycemia Associated with the α-Selective PI3K Inhibitor Alpelisib for the Treatment of Breast Cancer.

Alpelisib is an α-selective phosphatidylinositol 3-kinase inhibitor used for treating hormone receptor-positive (HR+), human epidermal growth receptor 2-negative (HER2-), PIK3CA-mutated locally advanced or metastatic breast cancer following disease progression on or after endocrine therapy. Hyperglycemia is an on-target effect of alpelisib affecting approximately 60% of treated patients, and sometimes necessitating dose reductions, treatment interruptions, or discontinuation of alpelisib. Early detection of hyperglycemia and timely intervention have a key role in achieving optimal glycemic control and maintaining alpelisib dose intensity to optimize the benefit of this drug. A glycemic support program implemented by an endocrinology-oncology collaborative team may be very useful in this regard. Lifestyle modifications, mainly comprising a reduced-carbohydrate diet, and a designated stepwise, personalized antihyperglycemic regimen, based on metformin, sodium-glucose co-transporter 2 inhibitors, and pioglitazone, are the main tools required to address the insulin-resistant hyperglycemia induced by alpelisib. In this report, based on the consensus of 14 oncologists and seven endocrinologists, we provide guidance for hyperglycemia management strategies before, during, and after alpelisib therapy for HR+, HER2-, PIK3CA-mutated breast cancer, with a focus on a proactive, multidisciplinary approach.

Immune-Related Thyroiditis as a Predictor for Survival in Metastatic Renal Cell Carcinoma.

Immune checkpoint inhibitors (CPI) are indicated for metastatic renal cell carcinoma (mRCC). Immune-related thyroiditis (irT), an immune-related adverse event (irAE), affects up to 30% of patients. We aimed to determine whether irT is associated with overall survival in mRCC. A retrospective cohort study of 123 consecutive patients treated with CPI for mRCC in a single center between 2015 and 2020 was conducted. Disease risk stratification was assessed by two methods: Heng criteria and a novel dichotomic stratification system to "Low risk" versus "High risk" adding number of metastatic sites. Thirty-eight percent of patients developed irT. In the general cohort, irT was not associated with a survival benefit. However, irT was associated with better survival in the poor risk group per Heng criteria (n = 17, HR = 0.25, p = 0.04) and in the novel "High risk" group (HR = 0.28, n = 42, p = 0.01), including after accounting for covariates in multivariate analysis (HR = 0.27, p = 0.003). Having any irAE was associated with improved survival in the whole cohort, with no significant correlation of any specific irAE, in either the whole cohort or the "High risk" group. We conclude that irT is an early and prevalent irAE, associated with prolonged survival in patients with poor/"High" risk mRCC.

Plasma Hemoglobin and Red Blood Cell Mass Levels as Dynamic Prognostic Markers for Progression and Survival in Pancreatic Neuroendocrine Tumors.

There are scarce data on readily available markers enabling immediate risk stratification and personalized management in patients with advanced pancreatic neuroendocrine tumors. This study explores the association of red blood cells-related parameters as prognostic markers in patients harboring pancreatic neuroendocrine tumors. Retrospective analysis of a tertiary medical center database, acquiring data of patients with pancreatic neuroendocrine tumors including demographics, tumor-related parameters and consecutive imaging results, vital status at last follow-up, and red blood cells parameters at baseline, last follow-up, and dynamics (last/baseline ratio). Univariate and multivariable analyses were performed. Sixty-seven patients were identified (mean age at diagnosis of 63±11 years, 56.7% males). Patients with disease progression had lower hemoglobin, red blood cells mass values and hematocrit at the last evaluation (p<0.001 for all comparisons), with red blood cells mass level<3.9 m/µl and a 6% and 9% relative reduction in hemoglobin and hematocrit levels, respectively, associated with an increased risk for disease progression. Similarly, patients deceased during the study period had lower hemoglobin, red blood cells mass values and hematocrit (p<0.03 for all) than those alive, at last follow-up. Eleven percent reduction in hemoglobin level was noted indicating a higher mortality risk (p=0.04). Negative hemoglobin and hematocrit dynamics were independently associated with increased risk for disease progression (p=0.03 and 0.049, respectively). In conclusion, decrease in red blood cells mass, hemoglobin and/or hematocrit levels are all associated with poor prognosis in patients with pancreatic neuroendocrine tumors. We suggest utilizing these parameters as complementary follow-up prognostic markers to radiologic imaging in this patients population.

Cardiorespiratory fitness and survival following cancer diagnosis.

AIMS: Data on the association of cardiorespiratory fitness with survival of cancer patients are limited. This study aimed to evaluate the association between midlife cardiorespiratory fitness and survival after a subsequent cancer diagnosis. METHODS: We evaluated 19,134 asymptomatic self-referred adults who were screened in preventive healthcare settings. All subjects were free of cardiovascular disease and cancer at baseline and completed a maximal exercise stress test. Fitness was categorised into age-specific and sex-specific quintiles according to the treadmill time and dichotomised to low (quintiles 1-2) and high fitness groups. RESULTS: The mean age was 50 ± 8 years and 72% were men. During a median follow-up of 13 years (interquartile range 7-16) 517 (3%) died. Overall, 1455 (7.6%) subjects developed cancer with a median time to cancer diagnosis of 6.4 years (interquartile range 3-10). Death from the time of cancer diagnosis was significantly lower among the high fitness group (Plog rank = 0.03). Time-dependent analysis showed that subjects who developed cancer during follow-up were more likely to die (P < 0.001). The association of cancer with survival was fitness dependent such that in the lower fitness group cancer was associated with a higher risk of death, whereas among the high fitness group the risk of death was lower (hazard ratio 20 vs. 15; Pfor interaction = 0.047). The effect modification persisted after applying a 4-year blanking period between fitness assessment and cancer diagnosis (Pfor interaction = 0.003). CONCLUSION: Higher midlife cardiorespiratory fitness is associated with better survival among cancer patients. Our findings support fitness assessment in preventive healthcare settings.

Skin exposure to UVB light induces a skin-brain-gonad axis and sexual behavior.

Ultraviolet (UV) light affects endocrinological and behavioral aspects of sexuality via an unknown mechanism. Here we discover that ultraviolet B (UVB) exposure enhances the levels of sex-steroid hormones and sexual behavior, which are mediated by the skin. In female mice, UVB exposure increases hypothalamus-pituitary-gonadal axis hormone levels, resulting in larger ovaries; extends estrus days; and increases anti-Mullerian hormone (AMH) expression. UVB exposure also enhances the sexual responsiveness and attractiveness of females and male-female interactions. Conditional knockout of p53 specifically in skin keratinocytes abolishes the effects of UVB. Thus, UVB triggers a skin-brain-gonadal axis through skin p53 activation. In humans, solar exposure enhances romantic passion in both genders and aggressiveness in men, as seen in analysis of individual questionaries, and positively correlates with testosterone level. Our findings suggest opportunities for treatment of sex-steroid-related dysfunctions.

Thyroid dysfunction and survival in cancer patients treated with immune checkpoint inhibitors: analyses from a large single tertiary cancer center database.

PURPOSE: We aimed to assess the incidence, clinical and biochemical course of immunotherapy-induced thyroiditis and its implication on patients' survival, based on an extensive clinical experience from a tertiary cancer center. METHODS: Analyses were based on data from the electronic medical records of cancer patients treated with CPIs. Data included demographic characteristics, cancer type, Thyroid function tests (TFT), and survival. RESULTS: Thyroid function tests were available for 934 patients. After excluding patients with impaired baseline TFT or levothyroxine treatment, 754 euthyroid patients were included in the core analyses. Of those, 301 (39.9%) patients developed thyroid dysfunction ('thyroiditis'). Thyroiditis was more prevalent in patients with renal cell carcinoma than other types of cancer. Survival rates were comparable in patients who developed thyroiditis and in those who did not. during the 5 years follow-up period, there was a non-significant trend toward improved survival in patients who developed TD in four predefined groups: melanoma, lung cancer, renal cell carcinoma, and transitional cell carcinoma. Nevertheless, we observed a highly significant survival benefit for patients with renal cell carcinoma who developed TD (HR = 0.19, 95% CI 0.06-0.60; p = 0.005). CONCLUSIONS: Thyroiditis is common, often asymptomatic, and is more prevalent in patients treated with combinations of nivolumab and PD-L1 inhibitors, and in patients with renal cell carcinoma. Thyroiditis was associated with a trend for a survival benefit, particularly in patients with renal cell carcinoma.

Low risk for all-cause mortality among patients with lung neuroendocrine tumors co-diagnosed with pituitary adenomas.

PURPOSE: Lung neoplasms often co-occur with pituitary adenoma (PA). However, whether co-diagnosis of lung neuroendocrine tumors (LNETs) and PA constitute a unique entity and the impact of such co-diagnosis on patients' outcome is yet to be defined. The study objective was to compare patients' clinical characteristics with LNET to patients co-diagnosed with PA. METHODS: A Retrospective, case-control study based on the Surveillance, Epidemiology, and End Results (SEER) registry database between 2000 and 2016. A total of 2947 patients with LNET, including 2913 with LNET alone ("Sporadic") and 34 patients with both LNET and PA ("LNET-PA"). RESULTS: PA preceded LNET diagnosis in 85.3% of patients and had higher rates among LNET patients (34/2947) than with any cancer (p < 0.00001) and compared to patients with non-small cell lung cancer (NSCLC) (15/2378, p = 0.047). LNET-PA patients were younger at diagnosis compared with NSCLC patients and PA (p = 0.04). Among patients <60 years with LNET, co-diagnosis with PA was associated with lower all-cause mortality (ACM) risk (Log-rank test, p = 0.03). Adjusted ACM risk of patients with LNET-PA was lower than sporadic LNET (hazard ratio 0.553, 95% confidence interval 0.309-0.99, p = 0.046), especially among Caucasians, and lower overall-mortality risk in patients <60 years with borderline statistical significance (p = 0.071). CONCLUSIONS: Patients with both LNET and PA constitute a distinct morbidity and mortality profile than sporadic LNET, possibly suggesting an undefined MEN syndrome. Additional studies to further investigate patients' natural course and genetic profile with these neoplasms are needed.

Capillary-leak syndrome: an unrecognized early immune adverse effect of checkpoint-inhibitors treatment.

Capillary-leak syndrome is strongly associated with cytokine activity states. It is an ill-recognized adverse effect of checkpoint inhibitors treatment, which are typically associated with cellular immune response. We describe two patients with capillary leak syndrome following immune checkpoint inhibitors treatment. We present linking mechanisms between checkpoint inhibitors, cellular immunity, cytokine action and endothelial damage. We suggest that capillary-leak syndrome is a unique adverse effect of immunotherapy, resulting from complex interactions between cellular and cytokine activation and that its expression is probably depending on inherent host immune variabilities.

Lay abstract Modern cancer treatment increasingly relies on means that encourage the patient's immune system to attack and destroy existing cancer cells. These means are very effective compared with standard treatments. However, the activation of the immune system is sometimes associated with untoward effects as a result of an attack of bystanding healthy tissues by the overactivated immune system and excessive inflammatory processes that accompany the immune response. We describe here two patients treated with immune checkpoint inhibiting drugs that developed transient extensive edema attributed to leakage of serum proteins and water from small blood vessels into the surrounding tissues (so-called 'capillary-leak syndrome'), after the drug-induced activation of the immune system. In both patients, the edema subsided following specific interventions.

Distinct Prognostic Factors in Sporadic and Multiple Endocrine Neoplasia Type 1-Related Pancreatic Neuroendocrine Tumors.

Pancreatic neuroendocrine tumors (PNET) may develop sporadically or in the context of hereditary syndromes. In patients with multiple endocrine neoplasia type 1 (MEN1), PNET is the leading cause of death. Our aim was to compare the mortality risk in sporadic and MEN1-related PNETs and identify high-risk populations. A retrospective Surveillance, Epidemiology, and End Results database analysis of patients with PNET was used. Patients with MEN1 were defined by syn/metachronous pituitary adenoma. Clinical data were retrieved, and all-cause mortality (ACM) risk was compared in univariate and multivariable analyses. The cohort included 569 patients (46.6% males) with sporadic (n=542) and MEN1-related (n=27) PNETs. Age at diagnosis of MEN1-related PNET was significantly younger than with sporadic PNETs (mean age 49.2±16.7 vs. 61.6±12.7 years, respectively; p < 0.001). Survival analysis showed a trend for a better outcome in patients with MEN1-related vs. sporadic PNET (Log-rank, p=0.09) and in subgroup analysis for patients with advanced disease (p=0.08). Furthermore, among patients followed expectantly, those with MEN1-related PNET had lower ACM risk than their sporadic counterparts (p=0.08). Multivariable analysis demonstrated lower ACM risk in patients diagnosed with MEN1 (hazard ratio 0.35, 95% confidence interval 0.11-1.2, p=0.09), further supporting the trend detected in the univariate analysis. In conclusion, our study demonstrates the distinct clinical profile of patients with MEN1-related PNET compared to sporadic disease and emphasizes the expertise required to accurately manage patients with PNET in this rare context. The cautious decision-making required before embarking on surgical intervention is further emphasized in this robust analysis of a large cancer database.

Sick Euthyroid Syndrome on Presentation of Patients With COVID-19: A Potential Marker for Disease Severity.

OBJECTIVE: Precise risk stratification and triage of coronavirus disease 2019 (COVID-19) patients are essential in the setting of an overwhelming pandemic burden. Clinical observation has shown a somewhat high prevalence of sick euthyroid syndrome among patients with COVID-19. This study aimed to evaluate the predictive value of free triiodothyronine (FT3) at the clinical presentation of COVID-19 for disease severity and death. METHODS: This retrospective cohort study was based on electronic medical records. The study was conducted at Sheba Medical Centre, a tertiary hospital where several acute and chronic wards have been dedicated to the treatment of patients with COVID-19. The primary outcome measure was death during hospitalization; secondary outcomes included hospitalization in intensive care, mechanical ventilation, and length of hospitalization. RESULTS: Of a total of 577 polymerase chain reaction-positive patients with COVID-19 hospitalized between February 27 and July 30, 2020, 90 had at least 1 measurement of thyroid-stimulating hormone, free thyroxine, and FT3 within 3 days of presentation. After applying strict exclusion criteria, 54 patients were included in the study. Patients in the lowest tertile of FT3 had significantly higher rates of mortality (40%, 5.9%, and 5.9%, P = .008), mechanical ventilation (45%, 29.4%, and 0.0%; P = .007) and intensive care unit admission (55%, 29.4%, and 5.9%, P = .006). In multivariate analyses adjusted for age, Charlson comorbidity index, creatinine, albumin, and white blood cell count. FT3 remained a significant independent predictor of death. CONCLUSION: FT3 levels can serve as a prognostic tool for disease severity in the early presentation of COVID-19.