Predictors of recurrence in pheochromocytoma.

Background: The recurrence rate of pheochromocytoma after adrenalectomy is 6.5-16.5%. This study aims to identify predictors of recurrence and optimal biochemical testing and imaging for detecting the recurrence of pheochromocytoma.

Methods: In this retrospective study we reviewed all patients who underwent adrenalectomy for pheochromocytoma during a 14-year period at a single institution.

Results: One hundred thirty-five patients had adrenalectomy for pheochromocytoma. Eight patients (6%) developed recurrent disease. The median time from initial operation to diagnosis of recurrence was 35 months. On multivariate analysis, tumor size >5 cm was an independent predictor of recurrence. One patient with recurrence died, 4 had stable disease, 2 had progression of disease, and 1 was cured. Recurrence was diagnosed by increases in plasma and/or urinary metanephrines and positive imaging in 6 patients (75%), and by positive imaging and normal biochemical levels in 2 patients (25%).

Conclusion: Patients with large tumors (>5 cm) should be followed vigilantly for recurrence. Because 25% of patients with recurrence had normal biochemical levels, we recommend routine imaging and testing of plasma or urinary metanephrines for prompt diagnosis of recurrence.