The giant of the giant schwannomas

Retroperitoneal malignant peripheral nerve sheath tumor replacing an absent kidney in a child

Malignant peripheral nerve sheath tumors (MPNSTs) are nonrhabdomyosarcoma soft tissue sarcomas with rare occurrence in children specially in the retroperitoneum. We describe a young child who presented with an abdominal mass. Both ultrasound and computed tomography revealed a large right-sided abdominal mass in the anatomic place of right kidney, while no kidney or ureter was observed at that side. He underwent surgical resection of the tumor with a primary impression of Wilms tumor. To the authors' knowledge, this is the first case of retroperitoneal malignant peripheral nerve sheath tumor and absent kidney. This case suggests the very rare probability of association of MPNSTs in children with genitourinary tract anomalies such as renal agenesis.

Atypical presentations of retroperitoneal giant schwannomas

Schwannomas are usually benign rare tumors that originating from Schwann cells of peripheral nerve sheaths. Presentation is generally varied and changed in a non-specific range from abdominal mass, flank pain to incidental findings. Herein we report 2 cases of retroperitoneal giant schwannomas with different clinical presentations, of whom one presented with vague abdominal pain, palpable abdominal mass for 4 years, swelling and bilateral hydronephrosis that caused by giant abdominal mass; the other one presented with right flank pain, rectal hemorrhage and lower extremities edema. Two patients were treated by complete surgical excision of masses. The histological and immunohistochemical diagnosis was reported as benign schwannoma. Both of patients are doing well and had no recurrence in 9 years and 28 months follow-up, respectively.

Low-back pain as the presenting sign in a patient with a giant, sacral cellular schwannoma: 10-year follow-up

Giant sacral tumors present unique challenges to surgeons because there is no established consensus regarding the best treatment options. The authors report on the care of and outcome in a patient presenting with low-back pain only, who underwent preoperative biopsy sampling and subsequent embolization of the feeding vessels of a giant, sacral cellular schwannoma. The main procedure was performed via a combined posterior-anterior approach with complete microsurgical removal of the tumor, without the use of instrumentation, bracing, or adjuvant radio- and chemotherapy. At the 10-year follow-up, no evidence of residual tumor, recurrence, or instability was recognizable. Giant, sacral cellular schwannomas can be aggressively completely removed without any significant morbidity, achieving long-term control of the disease.

[Benign presacral schwannoma producing obstructive uropathy. Clinical case and review of the literature]

We report a case of a presacral benign schwannoma which causes right hydroureteronephrosis without other clinical findings. After a fine-needle aspiration (FNA) biopsy under computed tomography (CT) guidance, a fusocellular tumour without athypia was demonstrated. With the initial diagnosis of benign schwannoma the patient was operated on, removing the tumour, and with the immunohistochemical examination (reactivity for S-100) this diagnosis was confirmed.