Hemangiopericytoma: report of a case involving the kidney

Renal hemangiopericytoma secondary to refractory hypertension in a child: A case report

Hemangiopericytoma is a rare perivascular tumor that often involves the extremities, pelvis, head and neck, and meninges, but rarely occurs in the kidney. The differentiation from renal cancer prior to surgery is extremely challenging; therefore, almost all cases of renal hemangiopericytoma are diagnosed by pathological examination. The majority of cases are identified in patients between the ages of 20 and 50 years of age, and a considerable proportion of patients exhibit hypertension, hypoglycaemia or additional paraneoplastic syndromes. The current study reports a rare case of renal hemangiopericytoma with drug refractory hypertension in a 14-year-old female. Following the complete resection of the tumor, the patient’s blood pressure returned to normal. No evidence of recurrence or metastasis was observed during a follow-up of 12 months following surgery. The present case indicated that surgery provides satisfactory outcomes and appears to be the most effective modality of treatment for renal hemangiopericytoma. Furthermore, this case also demonstrated that secondary hypertension may also recover following tumor excision.

Bilateral renal hemangiopericytoma

The first reported case of bilateral renal hemangiopericytoma is presented. The 19 previous renal hemangiopericytomas that have been reported in the world literature are reviewed. This lesion has afflicted patients ranging in age from sixteen to sixty-eight years (mean 41 years) with an equal sex distribution. Mortality from hemangiopericytoma of the kidney has been 50 percent, and the primary mode of therapy remains surgical.

Renal hemangiopericytoma: surgical, radiological and pathological implications

The first case of renal hemangiopericytoma presenting radiologically as a hypovascular mass is described. Preoperative diagnostic evaluation included ultrasonography, retrograde pyeloureterography, computerized tomography and angiography. Electron microscopy is helpful to distinguish this lesion from histologically similar juxtaglomerular cell tumors. Although renal hemangiopericytoma may appear benign on pathological examination it should be treated as a low grade malignancy and followed carefully.

Juxtaglomerular cell tumor of the kidney

The authors describe a juxtaglomerular cell tumor (JGCT) which caused severe hypertension in a 58-year-old man. Light microscopy showed a circumscribed tumor composed of interlacing cords and occasional nodules of relatively uniform cells with no mitotic activity. Rhomboid crystals characteristic of "prerenin" were present within the cytoplasm of tumor cells, and there was a close relationship between the tumor and unmyelinated nerve axons. Intracytoplasmic renin was demonstrated by immunofluorescence, and tumor granules were shown to contain zinc by electron-beam microanalysis. Review of 14 prior cases, with additional follow-up of 9, showed that no patient had developed recurrence, metastasis, or another tumor. Four patients, however, are hypertensive but probably because of secondary tumor effects rather than recurrent hyperreninism. The distinction of JGCT from hemangiopericytoma with renal involvement is important because of the high mortality associated with the latter. The authors conclude that JGCT is benign, but patients with JGCT may remain hypertensive postnephrectomy because of hypertensive angiopathy.

Spontaneous hypoglycemia associated with hemangiopericytoma of the kidney

We report the third case of renal hemangiopericytoma associated with spontaneous hypoglycemia. The clinical and pathological features suggest that excessive glucose storage by the tumor is an important factor in the pathogenesis of the hypoglycemia. Other possible mechanisms producing hypoglycemia associated with mesenchymal tumors are reviewed.