Clinical presentation, management, and research progress of adrenal schwannoma

To assess the accuracy of a dedicated adrenal computed tomographic (CT) protocol. One hundred sixty-six adrenal masses were evaluated with a protocol consisting of unenhanced CT, and, for those with attenuation values greater than 10 HU, contrast material-enhanced and delayed enhanced CT. Attenuation values and enhancement washout calculations were obtained. An adenoma was diagnosed if a mass had an attenuation value of 10 HU or less at unenhanced CT or a percentage enhancement washout value of 60% or higher. The final diagnosis was adenoma in 127 masses and non-adenoma in 39. Masses measuring more than 10 HU on unenhanced CT scans were confirmed at biopsy (n = 28) or were examined for stability or change in size at follow-up CT performed at a minimum interval of 6 months (n = 33). Thirty-six (92%) of 39 non-adenomas and 124 (98%) of 127 adenomas were correctly characterized. The sensitivity and specificity of this protocol were 98% and 92%, respectively. This protocol correctly characterized 160 (96%) of 166 masses. With a combination of unenhanced and delayed enhanced CT, nearly all adrenal masses can be correctly categorized as adenomas or non-adenomas.

Retroperitoneal schwannomas are rare, benign tumors. The aim of this study is to present our surgical experience with 7 such tumors. Between 1989 and 2004, 7 patients with pathologically proven retroperitoneal schwannomas were reviewed retrospectively. There were 6 male patients and 1 female patient, with a mean age of 43 years (range, 23 to 58 years). Two patients were symptomatic and presented with abdominal discomfort, and none of the patients suffered from von Recklinghausen's disease. All the patients underwent computed tomography scanning, which showed a heterogenous retroperitoneal mass, 4 of which were thought to arise from the adrenals. In 2 patients, calcification was seen in the tumors. All 7 of the patients had a preoperative diagnosis of a retroperitoneal tumor including 3 patients who were thought to have adrenal neoplasms (1 patient had a diagnosis of an adrenal neoplasm excluded on magnetic resonance imaging). Laparotomy and complete excision of tumors were performed in all the patients, and there was no morbidity or mortality. The schwannomas had a mean maximum diameter of 7.3 cm (range, 4 to 14 cm), and they were all benign. At a mean follow-up of 17 months (range, 3 to 48 months) postresection, all the patients remained free from recurrence. Retroperitoneal schwannomas are rare tumors that are difficult to diagnose preoperatively. Radiologic findings are usually nondiagnostic. The treatment of choice is complete surgical excision.