Bilateral pheochromocytomas: clinical presentation and morbidity rate related to surgery technique and genetic status.

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.