Adrenal ganglioneuromas: incidentalomas with misleading clinical and imaging features

Ganglioneuromas are benign neoplasms of the neural crest, occurring rarely in the adrenal glands. This study presents our experience regarding diagnostic and therapeutic management of these neoplasms and a review of the relevant literature.

Among 150 patients with of incidentalomas, we had 7 primary ganglioneuromas. Their clinical, imaging, and operative data were collected retrospectively, and the literature was reviewed using MEDLINE. There were 4 females and 3 males, with mean age of 50 years (range, 39-64). All neoplasms were discovered incidentally with ultrasonography and were evaluated subsequently with computed tomography (CT). One patient was studied further with (131)I-MIBG due to asymptomatic increased in urine vanillylmandelic acid, and 1 patient with history of breast cancer underwent additional FDG-PET/CT.

All but 2 patients were asymptomatic. Two patients complained of epigastric pain and hypertension, respectively. The preoperative mean size on CT was 6.8 cm, whereas the postoperative true mean histologic size was 7.7 cm. Both patients who were evaluated with radionuclide studies had false positive results, suggestive of pheochromocytoma and adrenal metastasis, respectively. Three patients underwent open adrenalectomy due to preoperative suspicion of carcinoma, and the remaining 4 underwent laparoscopic anterior adrenalectomy. Histologically, all 7 neoplasms were completely differentiated, mature ganglioneuromas. We had no mortality or significant morbidity. No recurrence occurred during a mean follow-up of 6 years (range, 1-18).

Adrenal ganglioneuromas are rare incidentalomas that can mimic primary or secondary adrenal malignancies as well as pheochromocytomas. Despite their usually large size, resection via laparoscopic approach is safe and effective.