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Subcapsular hemorrhage of adult wilms’ tumor
SUBCAPSULAR HEMORRHAGE OF ADULT WILMS’ TUMOR ˘ , OG ˘ UZ DI˙CLE, ENIS ˙IG ˘ CI˙, NAMI˙K ERDAG ˘ LU, AND TUG ˘ RUL PI˙RNAR MERAL KOYUNCUOG
Wilms’ tumor is a rare malignancy of kidney in adults. It usually cannot be differentiated from other renal masses preoperatively. This is a presentation of a case of adult Wilms’ tumor who developed spontaneous hemorrhage during radiological evaluation. As tumor rupture can change the stage of the tumor and alter the prognosis of the patient, urgent work-up and treatment is advised. Elsevier Science Inc., 1999 KEY WORDS:
Adult Wilms’ tumor; Hemorrhage; Radiography; Computed tomography; Magnetic resonance imaging.
INTRODUCTION Wilms’ tumor (nephroblastoma) is a malignant tumor of the kidney thought to arise from embryonic metanephric blastemal cells or stromal and epithelial derivatives. Although it accounts for 50% of all abdominal tumors in children, only 1% of all cases is encountered in adults (1). Necrosis and hemorrhage within the tumor are common features of renal malignancy. There are scattered reports of hemorrhage caused by Wilms’ tumor (2–4). We describe a case of adult Wilms’ tumor developing spontaneous subcapsular renal hematoma. CASE A 22-year-old woman was admitted to our hospital with a 4-week history of right flank pain. Two weeks before admission she experienced gross hematuria
which resolved spontaneously. On physical examination, a large nontender mass was palpated in the right upper quadrant of the abdomen. There was a right costovertebral angle tenderness. She denied any trauma. An abdominal sonogram demonstrated a 6 3 5 3 4-cm solid tumor in the lower pole of the right kidney. A computed tomography (CT) scan of the abdomen showed a well-defined heterogeneous renal mass on the right side causing calyceal distortion (Figure 1). Two days later, magnetic resonance imaging (MRI) study showed a subcapsular hematoma, 5 cm in thickness, in the right kidney in addition to the mass lesion (Figure 2). No tumor thrombus was seen in renal vein or inferior vena cava. Contrastenhanced MRI with fat-saturation did not reveal an enhancement in right renal pelvis indicating blood clot. Preoperative angiography depicted a hypovascular tumor at the same location. A right radical nephrectomy was performed. Histological examination revealed an anaplastic tumor consisting of blastemal cells with hyperchromatic nuclei and scanty cytoplasm. Tumor cells showed marked polymorphism, abnormal mitotic figures, and necrosis (Figure 3). The renal vascular pedicle and peripelvic fat tissue were invaded but right ureter was spared. Lymph nodes removed from renal hilum were intact. A diagnosis of undifferentiated anaplastic Wilms’ tumor (Stage II) was made. A metastatic work-up was negative. A postoperative radiotherapy and chemotherapy regimen was instituted.
DISCUSSION From the Dokuz Eylu¨l University School of Medicine, ˙Izmir, Turkey. Address correspondence to: Dr. Namık Erdag˘, Oyak Sitesi A-5 Blok 8/5, 35350 ˙Izmir-Turkey. Received July 21, 1998; accepted August 10, 1998. CLINICAL IMAGING 1999;23:44–46 Elsevier Science Inc., 1999. All rights reserved. 655 Avenue of the Americas, New York, NY 10010
Wilms’ tumor is a disease most common in children. The occurrence in adults is rare. A literature review revealed approximately 250 cases of adult Wilms’ tumor (5). However the exact number of cases is proba0899-7071/99/$–see front matter PII S0899-7071(98)00076-X
JANUARY/FEBRUARY 1999
SUBCAPSULAR HEMORRHAGE OF ADULT WILMS’ TUMOR
FIGURE 1. CT section through the lower portion of the right kidney shows a large heterogeneous mass replacing normal renal tissue and distorting pelvicalyceal structures.
bly fewer due to confusions in diagnostic criteria or inadequate documentation. Kilton et al. reviewed 192 cases in literature and only one quarter of them met the established criteria (6). Adult Wilms’ tumor has similar epidemiological and pathological features as in children. But prognosis is much poorer in adults. Survival rates for children and adults are 95% and 25%, respectively. This is probably due to more advanced stage of cases encountered in the latter age group. Wilms’ tumor usually presents as a large, fastgrowing abdominal mass with or without hematuria.
FIGURE 2. After contrast material administration, fatsaturated MRI scan (TR/TE 5 570/15) show hypointense hematoma against heavily enhanced normal renal parenchyma. Hematoma occupies subcapsular area. No pararenal invasion is noted. Right renal pelvis remains hypointense consistent with clot. Note the tumor is enhancing heterogeneously (arrowhead).
45
FIGURE 3. Polygonal cells with large nuclei represent primitive blastema. Proglomerular or tubular structures are not observed. Undifferentiated tumor cells show marked pleomorphism and cellular atypia. (H&E stain 3 400.)
Ultrasound shows a solid, well-defined inhomogeneous mass originating from cortical layer of kidney. CT reveals a globoid lesion enhancing less than surrounding renal parenchyma and a pseudocapsule consisting of compressed renal tissue. Calcification and fat are rarely seen in Wilms’ tumor. Large tumors originating from the right kidney can mimic hepatic masses. MRI better delineates renal capsule and extension of the tumor. It allows us to assess vascular invasion. Angiography demonstrates a hypovascular mass in contrast to renal carcinoma which is usually hypervascular. Some small wavy arteries can be seen entering the tumor (7). Kioumehr et al. reported that 75%–80% of patients have characteristic clinical and radiological findings (8). Although specimens from a renal tumor often demonstrate necrosis and hemorrhage, spontaneous renal or retroperitoneal hematoma formation caused by tumor rupture is rarely seen. Three percent of patients had preoperative tumor rupture in First National Wilms’ Tumor Study (NWTS). Of 94 patients who had spontaneous rupture of renal malignancies, two were Wilms’ tumor (4). In our case, no rupture was present in the initial radiological evaluation of the tumor. However, the mass evolved a spontaneous rupture and then a subcapsular hematoma formed. This was seen on MRI. Anaplastic type with unfavorable histology render the tumor more likely to bleed. Early diagnosis and treatment are important in Wilms’ tumor. Hemorrhage may progress rapidly and extend to the peritoneal cavity leading to tumor cell spillage. This complication changes the stage of the disease and alters the prognosis of the patient.
46
˘ ET AL. ERDAG
Therefore, Wilms’ tumor warrants urgent evaluation of the patient and an appropriate therapy.
REFERENCES 1. Babaian RJ, Skinner DG, Waisman J. Wilms’ tumor in the adult patient. Cancer 1980;45:1713–1719. 2. Heyns CF, Rossouw DJ. Spontaneous rupture of adult Wilms’ tumor. Cancer 1989;64:173–177. 3. Mishriki Y, D’Amore J, Harris M, Nathanson L. Bilateral adult Wilms’ tumor. Cancer 1987;59:1210–1213.
CLINICAL IMAGING VOL. 23, NO. 1
4. McDougal SW, Kursh ED, Pursky L. Spontaneous rupture of the kidney with perirenal hematoma. J Urol 1975;114:181–184. 5. Mydlo JH, Horowitz M, Del Rosario C, Cosgrove J, Macchia RJ. An unusual presentation of adult Wilms’ tumor. Urol Int 1996; 57(2):104–107. 6. Kilton L, Matthews MJ, Cohen MH. Adult Wilms’ tumor: a report of prolonged survival and review of literature. J Urol 1980; 124:1–5. 7. Kumar R, Amparo EG, David R, Fagan CJ, Morettin LB. Adult Wilms’ tumor: clinical and radiographic features. Urol Radiol 1984;6:164–169. 8. Kioumehr F, Cochran ST, Layfield L, Yaghmai I, Ngo C, Smith SR. Wilms’ tumor (nephroblastoma) in the adult patient. AJR 1989;152:299–302.
Wilms’ tumor is a rare malignancy of kidney in adults. It usually cannot be differentiated from other renal masses preoperatively. This is a presentation of a case of adult Wilms’ tumor who developed spontaneous hemorrhage during radiological evaluation. As tumor rupture can change the stage of the tumor and alter the prognosis of the patient, urgent work-up and treatment is advised. Elsevier Science Inc., 1999 KEY WORDS:
Adult Wilms’ tumor; Hemorrhage; Radiography; Computed tomography; Magnetic resonance imaging.
INTRODUCTION Wilms’ tumor (nephroblastoma) is a malignant tumor of the kidney thought to arise from embryonic metanephric blastemal cells or stromal and epithelial derivatives. Although it accounts for 50% of all abdominal tumors in children, only 1% of all cases is encountered in adults (1). Necrosis and hemorrhage within the tumor are common features of renal malignancy. There are scattered reports of hemorrhage caused by Wilms’ tumor (2–4). We describe a case of adult Wilms’ tumor developing spontaneous subcapsular renal hematoma. CASE A 22-year-old woman was admitted to our hospital with a 4-week history of right flank pain. Two weeks before admission she experienced gross hematuria
which resolved spontaneously. On physical examination, a large nontender mass was palpated in the right upper quadrant of the abdomen. There was a right costovertebral angle tenderness. She denied any trauma. An abdominal sonogram demonstrated a 6 3 5 3 4-cm solid tumor in the lower pole of the right kidney. A computed tomography (CT) scan of the abdomen showed a well-defined heterogeneous renal mass on the right side causing calyceal distortion (Figure 1). Two days later, magnetic resonance imaging (MRI) study showed a subcapsular hematoma, 5 cm in thickness, in the right kidney in addition to the mass lesion (Figure 2). No tumor thrombus was seen in renal vein or inferior vena cava. Contrastenhanced MRI with fat-saturation did not reveal an enhancement in right renal pelvis indicating blood clot. Preoperative angiography depicted a hypovascular tumor at the same location. A right radical nephrectomy was performed. Histological examination revealed an anaplastic tumor consisting of blastemal cells with hyperchromatic nuclei and scanty cytoplasm. Tumor cells showed marked polymorphism, abnormal mitotic figures, and necrosis (Figure 3). The renal vascular pedicle and peripelvic fat tissue were invaded but right ureter was spared. Lymph nodes removed from renal hilum were intact. A diagnosis of undifferentiated anaplastic Wilms’ tumor (Stage II) was made. A metastatic work-up was negative. A postoperative radiotherapy and chemotherapy regimen was instituted.
DISCUSSION From the Dokuz Eylu¨l University School of Medicine, ˙Izmir, Turkey. Address correspondence to: Dr. Namık Erdag˘, Oyak Sitesi A-5 Blok 8/5, 35350 ˙Izmir-Turkey. Received July 21, 1998; accepted August 10, 1998. CLINICAL IMAGING 1999;23:44–46 Elsevier Science Inc., 1999. All rights reserved. 655 Avenue of the Americas, New York, NY 10010
Wilms’ tumor is a disease most common in children. The occurrence in adults is rare. A literature review revealed approximately 250 cases of adult Wilms’ tumor (5). However the exact number of cases is proba0899-7071/99/$–see front matter PII S0899-7071(98)00076-X
JANUARY/FEBRUARY 1999
SUBCAPSULAR HEMORRHAGE OF ADULT WILMS’ TUMOR
FIGURE 1. CT section through the lower portion of the right kidney shows a large heterogeneous mass replacing normal renal tissue and distorting pelvicalyceal structures.
bly fewer due to confusions in diagnostic criteria or inadequate documentation. Kilton et al. reviewed 192 cases in literature and only one quarter of them met the established criteria (6). Adult Wilms’ tumor has similar epidemiological and pathological features as in children. But prognosis is much poorer in adults. Survival rates for children and adults are 95% and 25%, respectively. This is probably due to more advanced stage of cases encountered in the latter age group. Wilms’ tumor usually presents as a large, fastgrowing abdominal mass with or without hematuria.
FIGURE 2. After contrast material administration, fatsaturated MRI scan (TR/TE 5 570/15) show hypointense hematoma against heavily enhanced normal renal parenchyma. Hematoma occupies subcapsular area. No pararenal invasion is noted. Right renal pelvis remains hypointense consistent with clot. Note the tumor is enhancing heterogeneously (arrowhead).
45
FIGURE 3. Polygonal cells with large nuclei represent primitive blastema. Proglomerular or tubular structures are not observed. Undifferentiated tumor cells show marked pleomorphism and cellular atypia. (H&E stain 3 400.)
Ultrasound shows a solid, well-defined inhomogeneous mass originating from cortical layer of kidney. CT reveals a globoid lesion enhancing less than surrounding renal parenchyma and a pseudocapsule consisting of compressed renal tissue. Calcification and fat are rarely seen in Wilms’ tumor. Large tumors originating from the right kidney can mimic hepatic masses. MRI better delineates renal capsule and extension of the tumor. It allows us to assess vascular invasion. Angiography demonstrates a hypovascular mass in contrast to renal carcinoma which is usually hypervascular. Some small wavy arteries can be seen entering the tumor (7). Kioumehr et al. reported that 75%–80% of patients have characteristic clinical and radiological findings (8). Although specimens from a renal tumor often demonstrate necrosis and hemorrhage, spontaneous renal or retroperitoneal hematoma formation caused by tumor rupture is rarely seen. Three percent of patients had preoperative tumor rupture in First National Wilms’ Tumor Study (NWTS). Of 94 patients who had spontaneous rupture of renal malignancies, two were Wilms’ tumor (4). In our case, no rupture was present in the initial radiological evaluation of the tumor. However, the mass evolved a spontaneous rupture and then a subcapsular hematoma formed. This was seen on MRI. Anaplastic type with unfavorable histology render the tumor more likely to bleed. Early diagnosis and treatment are important in Wilms’ tumor. Hemorrhage may progress rapidly and extend to the peritoneal cavity leading to tumor cell spillage. This complication changes the stage of the disease and alters the prognosis of the patient.
46
˘ ET AL. ERDAG
Therefore, Wilms’ tumor warrants urgent evaluation of the patient and an appropriate therapy.
REFERENCES 1. Babaian RJ, Skinner DG, Waisman J. Wilms’ tumor in the adult patient. Cancer 1980;45:1713–1719. 2. Heyns CF, Rossouw DJ. Spontaneous rupture of adult Wilms’ tumor. Cancer 1989;64:173–177. 3. Mishriki Y, D’Amore J, Harris M, Nathanson L. Bilateral adult Wilms’ tumor. Cancer 1987;59:1210–1213.
CLINICAL IMAGING VOL. 23, NO. 1
4. McDougal SW, Kursh ED, Pursky L. Spontaneous rupture of the kidney with perirenal hematoma. J Urol 1975;114:181–184. 5. Mydlo JH, Horowitz M, Del Rosario C, Cosgrove J, Macchia RJ. An unusual presentation of adult Wilms’ tumor. Urol Int 1996; 57(2):104–107. 6. Kilton L, Matthews MJ, Cohen MH. Adult Wilms’ tumor: a report of prolonged survival and review of literature. J Urol 1980; 124:1–5. 7. Kumar R, Amparo EG, David R, Fagan CJ, Morettin LB. Adult Wilms’ tumor: clinical and radiographic features. Urol Radiol 1984;6:164–169. 8. Kioumehr F, Cochran ST, Layfield L, Yaghmai I, Ngo C, Smith SR. Wilms’ tumor (nephroblastoma) in the adult patient. AJR 1989;152:299–302.