Endocrine Abstracts

Background: Several new gene mutations have been reported in recent years to be associated with a risk of familial phaeochromocytomas (PHAEOs). However, it is unclear as to whether extensive genetic testing is required in all patients (pts).

Methods: Clinical data of consecutive patients operated for PHAEO over a decade in a tertiary referral centre were reviewed. Genetic screening was performed using a ten-gene panel: RET, VHL, SDHB, SDHD, SDHA, SDHC, SDHAF2, MAX, TMEM127, (NF1 when indicated; TMEM127 and SDHB if > 45 years and isolated PHAEO).

Results: A total of 157 patients (68 M: 43.3%, 89 F: 56.7%, age range 6–86 years, median 50.3±17.4 years) underwent laparoscopic (85%), open (10.5%), or laparoscopic converted to open (4.5%) adrenalectomy for unilateral (92%) or bilateral (8%) adrenal PHAEOs: 90 pts underwent genetic screening, in particular 60/90 (66.7%) pts presented with apparently sporadic tumours and 30/90 (33.3%) pts had genetic mutations. These were more frequently seen with bilateral PHAEOs (P=0.02). Mutations were seen in 12.2% pts for VHL, 10% NF1, 5.6% MEN2, 1.1% MEN3, 2.2% SDHD and 2.2% MAX. During a median follow-up of 50.4 months, 8% showed recurrent and 7% had metastatic disease. Younger pts showed a significant higher percentage of mutations compared to older pts (44% vs 17%). Twenty-seven percent of mutations were identified in pts with unilateral-non-recurrent PHAEOs within 5 years vs 62.5% in the recurrent-bilateral-metastatic group. Eighty-six of pts with bilateral disease had germline mutations (2 VHL, 2 RET, 1 NF1, 1 MAX).

Conclusions: The advent of rapid genetic screening for a ten-gene panel makes it feasible to screen large cohorts of pts, and allows for the prediction of bilateral and malignant disease and the screening of family members.