A RARE CASE OF RENAL HEMANGIOMA PRESENTING AS POLYCYTHEMIA BENJAMIN J. LEAK, JAVID JAVIDAN,
ABSTRACT Instances of renal cell carcinoma and erythropoietin-producing renal cysts presenting as polycythemia are well documented. To our knowledge, no case of hemangioma presenting as polycythemia has been reported. We present a case of a 39-year-old man with a 5-year history of polycythemia requiring phlebotomy every 3 months. Computed tomography revealed a 6 to 7-cm right upper pole renal mass. The patient underwent right radical nephrectomy, and pathologic examination revealed the mass to be a capillary hemangioma. The patient has not required phlebotomy for 1 year since the removal of the hemangioma. UROLOGY 57: 975iv–975v, 2001. © 2001, Elsevier Science Inc.
emangiomas of the kidney are rare, with only approximately 200 cases ever reported.1 To our knowledge, no other case of renal hemangioma presenting with polycythemia cured by nephrectomy has been reported. CASE REPORT
A 39-year-old man with a 5-year history of polycythemia had a normal physical examination and had no gross or microscopic hematuria present. The patient’s serum hemoglobin was greater than 22 g/dL (normal range 13.5 to 17.0), and he required phlebotomy every 3 months. He had a normal bone marrow biopsy, and his serum erythropoietin was 18.4 mU/mL (normal range 0 to 27). After searching on the Internet for the possible causes of polycythemia, the patient persuaded his internist to obtain a computed tomography scan. Computed tomography revealed a 6 to 7-cm, poorly defined, right upper pole, renal mass (Fig. 1), and renal carcinoma could not be excluded. Right radical nephrectomy was performed. His convalescence was uneventful, and the patient was discharged from the hospital 4 days later. One year after nephrectomy, the patient’s serum hemoglobin was 14.6 g/dL, and he no longer required phlebotomy. From the Department of Urology, Henry Ford Hospital, Detroit, Michigan Address for correspondence: Benjamin J. Leak, M.D., 26375 Halsted, No. 10, Farmington Hills, MI 48331 Submitted: September 27, 2000, accepted (with revisions): December 20, 2000
© 2001, ELSEVIER SCIENCE INC. ALL RIGHTS RESERVED
FIGURE 1. Computed tomography scan demonstrating a 6 to 7-cm, poorly defined mass of the upper pole of the right kidney.
Gross pathologic examination of the specimen revealed a 5.0 ⫻ 5.0 ⫻ 4.0-cm, well-circumscribed, centrally scarred, red-brown lesion in the right upper pole grossly abutting the renal capsule. Histologically, the tumor consisted primarily of a proliferation of small capillary vessels consistent with capillary hemangioma (Fig. 2). No significant adipose tissue component was noted, nor was there any spread into the perinephric fat or renal vein. The tumor stained positive for factor VIII, confirming its vascular nature, and negative for HMB-45, 0090-4295/01/$20.00 PII S0090-4295(01)00910-4
FIGURE 2. (A) Proliferation of small capillaries consistent with a hemangioma. (B) Positive stain with factor VIII, confirming the tumor’s vascular nature.
confirming the absence of modified smooth muscle, which would be present in renal angiomyolipoma. COMMENT Renal hemangiomas are rare occurrences. The tumors usually present in the fourth decade, are unilateral, and are between 1 and 2 cm. Renal hemangiomas most commonly occur in the lamina propria of the pelvis (48.7%), pyramid of the kidney (42.1%), or the renal cortex (9.2%), with hematuria the most common presenting complaint.2 Erythropoietin-producing renal cysts and renal cell carcinoma that cause polycythemia have been well described. Other tumors known to occasionally cause polycythemia include hepatoma, cerebellar hemangioblastoma, uterine fibromyoma, meningioma, pheochromocytoma, Wilms’ tumor, and liver hamartoma. Erythropoietin is a glycoprotein hormone produced primarily in adults by peritubular interstitial fibroblasts in the inner cortex of the kidney, but it is also produced in the liver in both hepatocytes and interstitial fibroblasts.3 To our knowledge, no previous references to polycythemia associated with renal hemangiomas have been reported. Differentiating renal cell carcinoma from a benign renal hemangioma is of great clinical signifi-
UROLOGY 57 (5), 2001
cance, but distinguishing between the two masses with preoperative imaging is difficult. Computed tomography, intravenous urography, and abdominal ultrasonography typically contribute little to discriminating between renal cell carcinoma and renal hemangioma.4 Selective renal angiography typically shows hypervascularity and a lack of staining on the nephrogram phase with renal hemangioma. However, hypovascularity may also occur, making it indistinguishable from renal cell carcinoma.2 Renal hemangiomas are slow growing, and a conservative approach has been recommended in their treatment.1,2,4 Therefore, as this case demonstrates, when polycythemia and a renal mass are both present, not only renal cell carcinoma but also renal hemangioma must be considered. This could alter the operative approach. REFERENCES 1. Wang T, Palazzo JP, Mitchell D, et al: Renal capsular hemangioma. J Urol 149: 1122–1123, 1993. 2. Jahn H, and Nissen HM: Haemangioma of the urinary tract: review of the literature. Br J Urol 68: 113–117, 1991. 3. Spivak J: Erythrocytosis, in Hoffman R, Benz E, Shattil S, et al (Eds): Hematology—Basic Principles and Practice, 3rd ed. New York, Churchill Livingstone, 2000, pp 388 –393. 4. Okuno T, Ando M, Arisawa C, et al: A case of perirenal hemangioma mimicking renal cell carcinoma. Int J Urol 6: 104 –106, 1999.