Benign adrenal and suprarenal retroperitoneal schwannomas can mimic aggressive adrenal malignancies: case report and review of the literature

Abstract

The suprarenal retroperitoneum and adrenal gland is a rare site of origin for benign schwannomas which frequently present as larger and more aggressive lesions than schwannomas identified elsewhere. These tumors are often surgically excised. We present a case of an 81-year-old asymptomatic man presenting with an incidental 10 cm left suprarenal retroperitoneal mass identified on CT. The mass was indiscernible from the adrenal gland, demonstrating heterogeneous enhancement with a centrally cystic/necrotic core, and punctate calcifications. Subsequent core needle biopsy demonstrated a benign adrenal schwannoma. The lesion has been managed conservatively with imaging follow up and without complication. DISCUSSION: Our review of the literature identifies 121 reported in vivo benign adrenal and suprarenal schwannomas published to date with imaging features available for 90 cases (74%). All cases were encapsulated with the average size measuring over 6.5 cm. Fifteen percent (13/84) of reported lesions measured over 10 cm at presentation. Punctate calcification was present in 50% (26/52) of reporting cases. Nearly 50% (40/86) of cases demonstrate cystic/necrotic appearances on imaging. Despite aggressive appearances, our case demonstrates that biopsy and surveillance may represent a reasonable alternative to surgery in suboptimal surgical candidates.

An unusual finding after adrenal surgery: a case series of adrenal schwannomas

“…Hormonal inactivity of these masses may not be helpful to clinicians for their differential diagnosis; nevertheless, imaging findings may confuse clinicians for preoperative diagnosis. Heterogeneous imaging findings such as thick walls, mixed cystic solid components, calcification, and necrosis may cause suspicion of pheochromocytoma and adrenocortical carcinoma ( 5 ). In MRI studies, intensity characteristics of adrenal schwannomas may be low in T1-weighted images and high in T2-weighted images.…”

“…Adrenal schwannomas may be confused with adrenocortical cancer, adrenal metastasis, or pheochromocytoma due to their imaging findings ( 5 ). In this case series, we present characteristics, preoperative clinical, radiologic, and postoperative findings of three different adrenal schwannomas with suspicious findings in imaging studies for malignancy or pheochromocytoma; however, after adrenal surgery, the diagnosis of benign adrenal schwannoma was revealed in pathological evaluation.…”

Clinical presentation, management, and research progress of adrenal schwannoma

“…The diagnosis of AS during pregnancy has been reported in the literature. Retroperitoneal schwannoma can mimic the characteristics of female genital masses during pregnancy, such as adnexal mass, ectopic pregnancy, and so on ( 11 ). However, because we cannot use contrast media during pregnancy, this will make our diagnosis more difficult.…”

“…Benign schwannoma has a good prognosis, but there is the possibility of recurrence and malignant transformation. Wilson et al ( 11 ) recently reviewed and identified 121 reported ASs in the literature, of which the average size of the tumor was about 6.5 cm, about 50% of the reported cases had punctate calcification, and about 50% of the cases showed cystic/necrotic changes on imaging. In our case group, the incidence of tumor necrosis/cystic changes in imaging findings was 87.5%, which was much higher than the average level.…”