Schwannoma retroperitoneal sincrónico con carcinoma renal de células claras

Background

Schwannomas are well-encapsulated tumors arising from the peripheral nerve sheaths and they appear in young or middle-aged adults. These tumors make up 0.5-2.7% of retroperitoneal tumors. The majority of schwannomas are benign and single, although multiple tumors have been described. There are reports of malignant cases associated with von Recklinghausen's disease and melanocytic nevus in children, with hypercalcemia of parathyroid origin.

Clinical case

A 54-year-old woman had a past history of tubular adenoma of the colon. Her current illness began with lower urinary tract symptoms, mainly of storage, along with total gross hematuria with no clots. An abdominal tomography scan revealed a 21 mm contrast-enhanced left kidney upper pole lesion and a 53 × 48 × 32 mm solid lesion adjacent to the left adrenal gland. The latter had well-defined regular edges that anteriorly displaced the pancreas and splenic artery, with punctiform intraparenchymal calcifications. Left partial nephrectomy of the upper pole was performed and the histopathology study reported clear cell carcinoma limited to the kidney, Fuhrman 2, with no lymphovascular invasion.

Discussion

Schwannomas in the retroperitoneum are rare, making up approximately 1% of retroperitoneal tumors. Patient age at the time of diagnosis varies from 20 to 50 years. Incidence has been observed to be slightly more frequent in women than in men. When symptoms present, the most frequent are abdominal pain, abdominal distension, and lumbalgia.

Conclusions

Retroperitoneal schwannoma is a rare disease. Its presentation is nonspecific and it is generally an incidental finding. Computed tomography and magnetic resonance are useful for the preoperative approach.