Clinical features and outcomes of adrenal schwannoma: a study of 13 cases from a single centre.

Background Adrenal schwannomas (AS) are extremely rare neoplasms. This study shares our experience regarding the diagnosis and operative management of AS. Methods Clinical details, radiologic, laboratory, and pathologic findings as well as follow-up data were analysed retrospectively for 13 AS patients who accepted surgery at a tertiary referral hospital in China between 1 January 1996, and 31 December 2017. Results The mean age of the patients at diagnosis was 44.7 ± 13.7 years (range 19-62 years; male: female ratio, 1:1.16), of whom seven patients had unilateral AS on the right side, and the remaining six on the left side. None of the cases were hormonally active. None of the 13 cases were diagnosed as AS by CT imaging before the operation. Among the patients, ten were asymptomatic. The mean preoperative size was 7.1 ± 3.2 cm (range 1.6-12.6 cm). All patients underwent surgery, with open adrenalectomy in five patients and laparoscopy in eight patients. The mean tumor size on pathologic examination was 6.8 ± 3.0 cm (range 3.0-11.7 cm). The surgical specimens were confirmed by pathological examination. During a median follow-up of 60.8 ± 17.7 months, no patients showed recurrence or metastasis. Conclusion The preoperative diagnosis of AS remains difficult despite the advances in imaging examinations. After complete resection, the prognosis of AS is excellent.