Composite Pheochromocytoma-Paraganglioma With Ganglioneuroma: A Dual-Center Clinical Experience.

Context: Cells derived from neural crest populate several organs. A particular precursor cell, sympathogonia, gives rise to pheochromoblasts and neuroblasts. Due to common origin, tumors originating from pheochromoblasts, such as pheochromocytoma (PHEO) and paraganglioma (PGL), may rarely coexist with ganglioneuroma (GN).

Objective: We evaluated clinical, biochemical, and radiological characteristics of patients with composite PHEO/PGL and GN (PPGL-GN) and compared them to patients with PHEO.

Methods: In this retrospective, dual-center, observational, case-control study, we identified patients with PPGL-GN. Similarly, we identified a control group of patients with PHEO who underwent laparoscopic adrenalectomy. All diagnoses were confirmed on histology. Descriptive statistics were used to summarize demographic and clinical data.

Results: We identified 19 consecutive patients with PPGL-GN and 86 patients with PHEO. Patients with PPGL-GN, compared to those with PHEO, were younger (aged 46.0 vs 50.8 years; = .03), had higher rate of underlying genetic disorders (47.4% vs 23.2%; = .03), and had fewer functioning tumors (89.5% vs 100%; = .002). There was no difference in the median radiological tumor size or the precontrast computed tomography density. Disease recurrence (at another site) was noted in 15.8% of PPGL-GN patients who had a median follow up of 14.6 months, as opposed to no disease recurrence in patients with PHEO. There was no documented recurrence at the tumor bed and no metastasis in both groups.

Conclusion: Patients with PPGL-GN were younger and had a higher occurrence of underlying genetic disorders compared to PHEO. However, PPGL-GN was radiologically indistinguishable from PHEO. The higher observed disease recurrence of PPGL-GN reinforces vigilant postoperative follow-up.