SUO 2017: Long Term Outcomes For Patients With Von Hippel Lindau And Pheochromocytoma: Defining The Best Candidates For Active Surveillance

Washington, DC (UroToday.com) Introduction: Patients with a germline mutation in the Von Hippel-Lindau (VHL) gene have a 7-18% lifetime risk of developing pheochromocytoma. In this study the authors aimed to evaluate the oncologic and functional outcomes of patients with VHL associated pheochromocytoma who underwent a period of active surveillance.

Methods: Patients were included in the study if they met the following criteria: 1) Confirmed mutation in the VHL tumor suppressor gene, 2) History of surgery for either pheochromocytoma or paraganglioma, 3) At least 10 years of follow-up at the NIH. The active surveillance cohort consisted of any patients who underwent repeat imaging at the NIH. The surveillance cohort was split into three subsets based on mass size: less than 1 cm, 1-2 cm, and greater than 2cm and the growth rate per year was calculated using the following formula: (size [end of surveillance period]- size [beginning of surveillance period])/ time(years).

Results: In total, there were 72 patients who met all inclusion criteria from 54 families with median length of follow up of 17 years. There were 38 masses that underwent a period of surveillance in 26 patients. The median age at which surveillance was began was 30 (range 7-61). The median time on surveillance was 4.3 years (range 0.3 -20.1). The median size of mass when starting surveillance was 1.0 cm (range 0.3-2.5 cm) and the median size when the mass was resected was 2.0 (range 0.3-4.5). The median growth rate for all masses was 1mm per year (range -0.23-1.06). The median growth rate for masses under 1.0 cm was 0.3mm per year. The median growth rate for masses between 1.0 and 2.0 cm was 1.2 mm per year. The median growth rate for masses larger than 2.0 cm was 3.2 mm per year (p=0.018). No patients on surveillance developed metastatic disease.

Conclusion: The authors concluded that active surveillance is a safe strategy for the management of pheochromocytoma in patients with germline VHL alterations. Growth rates appear to increase dramatically with increasing size of the tumors. It appears that patients with masses smaller than 2 cm are the optimal candidates for active surveillance.

Presented by: Thomas Sanford, NCI, Bethesda, USA

Written by: Hanan Goldberg, MD, Urologic Oncology Fellow (SUO), University of Toronto, Princess Margaret Cancer Centre, @GoldbergHanan, at the 18th Annual Meeting of the Society of Urologic Oncology, November 29-December 1, 2017 – Washington, DC