Hypoxia-inducible factors (HIF) 2α and 1α are the major oxygen-sensing molecules in eukaryotic cells. HIF2α has been pathogenically linked to paraganglioma and pheochromocytoma (PPGL) arising in sympathetic paraganglia or the adrenal medulla (AM), respectively. However, its involvement in the pathogenesis of paraganglioma arising in the carotid body (CB) or other parasympathetic ganglia in the head and neck (HNPGL) remains to be defined. Here, we retrospectively analyzed HIF2α by immunohistochemistry in 62 PPGL/HNPGL and human CB and AM, and comprehensively evaluated the HIF-related transcriptome of 202 published PPGL/HNPGL. We report that HIF2α is barely detected in the AM, but accumulates at high levels in PPGL, mostly (but not exclusively) in those with loss-of-function mutations in VHL and genes encoding components of the succinate dehydrogenase (SDH) complex. This is associated with upregulation of EPAS1 and the HIF2α-regulated genes COX4I2 and ADORA2A. In contrast, HIF2α and HIF2α-regulated genes are highly expressed in CB and HNPGL, irrespective of VHL and SDH dysfunctions. We also found that HIF2α and HIF1α protein expressions are not correlated in PPGL nor HNPGL. In addition, HIF1α-target genes are almost exclusively overexpressed in VHL-mutated HNPGL/PPGL. Collectively, the data suggest that involvement of HIF2α in the physiology and tumor pathology of human paraganglia is organ-of-origin-dependent and HIF1α-independent.

Introduction: It is estimated that 30–40% of patients with apparently sporadic pheochromocytomas (PHEOs) have an inherited predisposition syndrome. The aim of our study was to develop a predictive model of hereditary PHEO based on the clinical, hormonal, and radiological features present at the diagnosis of patients with PHEOs. Methods: A retrospective multicenter cohort study of patients with PHEOs with available genetic study from 18 tertiary hospitals. Clinical, biochemical, and radiological features were used to build a multivariate logistic regression model. The estimation of all possible equations was used to select the model with the best diagnostic accuracy (lower Akaike index). Results: A total of 245 patients were included: 169 (69.0%) patients with sporadic PHEOs and 76 (31%) with hereditary PHEOs. The parsimonious predictive model with the highest diagnostic accuracy for the prediction of hereditary PHEO combined the variables age, non-cardiovascular disease, urinary norepinephrine levels, and tumor size. The area under the ROC curve of this model was 0.800 (0.705–0.887). Based on the predictive model, the probability of hereditary PHEO in patients older than 60 years with cardiovascular disease, high levels of urinary norepinephrine and unilateral PHEOs >60 mm was <2%. And if the age was above 80 years, lower than 1%. The probability of sporadic PHEO linearly increased with age (MH Test for linear Trend: χ2 (1) = 30.05; p < 0.001). Conclusion: In certain populations such as old patients with cardiovascular disease, with high levels of urinary norepinephrine and large tumors in which the probability of hereditary PHEO is very low, genetic testing could be avoided in the absence of specific suspicion.

Introduction: Historically, Multiple Endocrine Neoplasia type 1 (MEN1)-related pituitary adenomas (PAs) were considered more aggressive and treatment-resistant than sporadic PAs. However, recent studies suggest similarities in their behavior. This study aimed to evaluate the long-term outcomes of MEN1 PAs and identify predictive factors.Methods: Nationwide multicenter retrospective cohort study of MEN1-related PAs with a minimum 1-year follow-up, collecting patient demographics, germline MEN1 pathogenic variants (PV), PA size, secretory profile, radiological characteristics, treatments, and outcomes.Results: We analyzed 84 PAs, 69%in females and 31% in males (P<0.001), diagnosed at a mean age of 35.2±14.9 years, mostly through screening (60.7%). Median follow-up was 9 years (IQR:4-16). Prolactin-secreting PAs (PRLomas) (53.5%) and microadenomas (65.5%) were most common. Dopamine agonist treatment was first line for 16 macroPRLomas and 25 microPRLomas, 60.9% of them achieved PRL normalization. There was no significant association observed with tumor size, sex, treatment duration or MEN1 PV. The risk of progression from micro-PA to invasive macro-PA was 7.2% (4/55), after 8 years (IQR:4-13), all of them were microPRLomas. Kaplan-Meier estimation curve showed significantly higher progression probability in microPRLomas than in other microadenomas subtypes (P=0.017) or microNFPAs (P=0.032). No differences were found between sex, age, or germline MEN1 PV.Conclusion: MEN1-related micro-PAs have a low risk of progressing to invasive macro-PAs, regardless of sex, age at diagnosis, or MEN1 germline PV. The risk is higher for microPRLomas over the long term. Therefore, long-term surveillance with reduced frequency, rather than intensive short-term monitoring, may be appropriate for patients with MEN1-related PAs.

Context: Adrenocortical carcinoma (ACC) is a rare, aggressive malignancy with a high risk of postoperative recurrence. Although adjuvant mitotane is commonly used, its potential for achieving cure rather than simply postponing inevitable recurrence remains uncertain. Objective: This study investigates whether mitotane impacts ACC recurrence patterns by preventing or delaying recurrence. Methods: This retrospective analysis used data from the ICARO-GETTHI/SEEN registry, which includes 36 Spanish hospitals. Recurrence in nonmetastatic ACC patients after resection was analyzed using Cox models, flexible longitudinal models, and mixture cure models to evaluate the impact of mitotane. Results: Among 244 patients, 133 (52%) received adjuvant mitotane, with therapeutic levels monitored in 84%. Findings suggest a possible “cure fraction” with a 32.5% estimated 30-year cure rate (95% CI, 23.4%-45.0%). Cox regression indicated a 39% reduced recurrence risk (HR 0.61; 95% CI, 0.39-0.95) for mitotane-treated patients, with effects diminishing over 24 months. Mixture cure models suggest mitotane primarily delays rather than prevents recurrence. Effect modification analysis showed significant benefit in male patients (HR 0.33; 95% CI, 0.16-0.69), younger patients, tumors with higher Ki-67% (modeled as a continuous variable), and those with venous invasion (HR 0.47; 95% CI, 0.27-0.82), with potential synergy when combined with radiotherapy. Conclusion: This study underscores the intriguing possibility that adjuvant mitotane delays recurrence, yet questions remain as to its curative capacity. The early benefit suggests a cytostatic effect, but certain subgroups—especially males, younger individuals, and those with high-risk tumors—may experience a more durable outcome. Further research is needed to explore mitotane's curative potential in ACC management.

Purpose: to perform an external validation of our predictive model to rule out pheochromocytoma (PHEO) based on unenhanced CT in a cohort of patients with PHEOs and adenomas who underwent adrenalectomy. Methods: The predictive model was previously developed in a retrospective cohort of 1131 patients presenting with adrenal lesions. In the present study, we performed an external validation of the model in another cohort of 214 patients with available histopathological results. Results: For the external validation, 115 patients with PHEOs and 99 with adenomas were included. Our previously described predictive model combining the variables of high lipid content and tumor size in unenhanced CT (AUC-ROC: 0.961) had a lower diagnostic accuracy in our current study population for the prediction of PHEO (AUC: 0.750). However, when we excluded atypical adenomas (with Hounsfield units (HU) > 10, n = 39), the diagnostic accuracy increased to 87.4%. In addition, in the whole cohort (including atypical adenomas), when MRI information was included in the model, the diagnostic accuracy increased to up to 85% when the variables tumor size, high lipid content in an unenhanced CT scan, and hyperintensity in the T2 sequence in MRI were included. The probability of PHEO was <0.3% for adrenal lesions 10 HU and without hyperintensity in T2. Conclusion: Our study confirms that our predictive model combining tumor size and lipid content has high reliability for the prediction of PHEO when atypical adrenal lesions are excluded. However, for atypical adrenal lesions with >10 HU in an unenhanced CT scan, MRI information is necessary for a proper exclusion of the PHEO diagnosis.

Introduction: This study explores the under-investigated area of obesity-related discrimination and stigmatization across different countries, specifically comparing Spain (Europe) and Egypt (Middle East). Methods: We conducted a cross-sectional observational study involving 2,090 participants from both countries. Participants completed three well-validated questionnaires to assess their attitudes toward obesity, experiences of weight-related stigma, and internalization of weight bias: Antifat Attitudes Scale (AFA), Stigmatizing Situations Inventory (SSI), and Weight Bias Internalization Scale (WBIS). Participants were categorized into four groups based on body mass index (BMI) and history bariatric surgery. Results: Egyptian participants (BMI = 30.2 ± 6.7 kg/m2 [range: 18.5–69.0 kg/m2]) showed significantly higher aversion toward obesity, as indicated by higher AFA score, compared to their Spanish counterparts (BMI = 35.4 ± 10.1 kg/m2 [18.5–71.9 kg/m2]). In contrast, Spanish participants reported higher levels of weight bias internalization with increasing BMI, while in Egypt, this association was negative. The association of bariatric surgery on stigma reduction also differed between the countries. Multivariate analysis revealed that residing in Egypt was an independent risk factor for higher scores in AFA and WBIS (odds ratio 8.20 [95% confidence interval: 6.78–9.62], p < 0.001 and odds ratio (OR) 6.28 [95% CI: 4.78–7.78], p < 0.001, respectively). In contrast, Spaniards experienced more stigmatizing situations than Egyptians (OR −2.54 [95% CI: 6.78–9.62], p < 0.001). Conclusion: Our study underscores the complex and diverse nature of obesity-related attitudes across cultures. Understanding these cultural differences is crucial for developing effective, culturally sensitive strategies to tackle weight stigma. This research opens avenues for further studies and interventions tailored to cultural contexts.