RESUMO
Background: Pheochromocytomas (PHEOs) are rare catecholamine-secreting adrenal tumors. Approximately 60-90% of bilateral PHEOs are hereditary. We retrospectively analyzed the clinical characteristics of patients with bilateral PHEOs and the morbidity rate (malignancy, tumor recurrence and adrenal insufficiency (AI) rate) related to surgery technique and genetic status of the patients. Results: Fourteen patients (12.5%, nine women, five men) had synchronous or metachronous bilateral PHEOs (out of 112 PHEO patients who underwent surgery between 1976 and 2021). The median age at diagnosis was 32 years (9-76) (three were children). Nine patients (64.2%) presented synchronous bilateral tumors, five (35.7%) contralateral metachronous tumors, 2-12 years after the first surgical intervention; three (21.4%) were metastatic. Median follow-up: 5 years (1-41), IQR 19 months. A total of 78.5% had a germline mutation (eight RET gene with MEN2A syndrome, three VHL syndrome, three not tested). Post-surgery recurrence was noted in 16.6% of patients (one with MEN2A syndrome and metastatic PHEOs, one with VHL syndrome), with similar rates after total adrenalectomy or cortical-sparing adrenal surgery. AI was avoided in 40% after cortical-sparing surgery. Conclusion: Bilateral PHEOs are usually associated with genetic syndromes. The surgical technique for patients with hereditary bilateral PHEOs should be chosen based on a personalized approach, as they are at higher risk for developing new adrenal tumors requiring additional surgeries.
RESUMO
BACKGROUND/AIM: Vitamin D deficiency and vitamin D receptor (VDR) gene polymorphisms are involved in a variety of biological processes including cell proliferation, apoptosis, and adhesion in malignant tumors. This study investigated whether vitamin D levels and genetic variations of VDR are risk factors for thyroid cancer. PATIENTS AND METHODS: Patients who underwent surgery for differentiated thyroid carcinoma (n=113) and those with benign thyroid pathology (n=150) were genotyped for VDR gene polymorphisms (ApaI, TaqI, FokI, and BsmI) and their 25(OH)D levels were simultaneously measured. Demographic data and histopathologic reports were also acquired for all patients. RESULTS: Vitamin D levels were significantly lower in the thyroid cancer group (p=0.03). FokI and TaqI polymorphisms were more frequent in the thyroid cancer patients (p<0.001). Compared to control, the proportion of the FokI Ff genotype was increased (p<0.0006) and the proportion of the TaqI Tt genotype was also higher among patients with thyroid cancer (p<0.0001). The Ff genotype of FokI was also associated with multifocality, invasive pattern, and risk for local metastasis. CONCLUSION: The VDR gene polymorphism FokI may be associated with the risk of thyroid cancer and its more aggressive forms.
