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Strategy for management of retroperitoneal tumors with caval tumor thrombus
Journal of Pediatric Surgery (2011) 46, 2065–2070
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Strategy for management of retroperitoneal tumors with caval tumor thrombus Nini Khozeimeh a , Pranava Sinha b , Jeffrey S. Dome c , Philip C. Guzzetta Jr a,⁎ a
Department of Pediatric Surgery, Children's National Medical Center, Washington, DC 20010, USA Department of Cardiac Surgery, Children's National Medical Center, Washington, DC 20010, USA c Department of Hematology and Oncology, Children's National Medical Center Washington, DC b
Received 18 March 2011; revised 8 June 2011; accepted 25 June 2011
Key words: Retroperitoneal tumors; Intracaval tumor extension
Abstract The surgical management of retroperitoneal tumors extending into the inferior vena cava (IVC) can be challenging. Although Wilms' tumor is the most common retroperitoneal tumor extending into the IVC, one must approach these tumors systematically as other diagnoses are possible. We present 4 consecutive cases of retroperitoneal tumors with IVC extension as a basis for a management strategy in approaching these patients. Despite similar presentations, these cases illustrate the nuances in surgical management and need for multidisciplinary care with the pediatric oncologists, pediatric surgeons, and pediatric cardiac surgeons. © 2011 Elsevier Inc. All rights reserved.
The management of tumors that extend into the inferior vena cava (IVC) is determined by multiple factors including [1] extent of tumor thrombus, [2] possibility of tumor embolus, [3] tumor histology, [4] responsiveness of the tumor to chemotherapy, and [5] tumor stage at presentation. Imaging studies can accurately delineate the extent of vascular invasion and often suggest the diagnosis of these tumors. Both factors may modify the surgical approach and consideration of the administration of neoadjuvant therapy. Wilms' tumor is the most common retroperitoneal tumor extending into the IVC in a child, but other diagnoses are also possible. One must approach these tumors systematically. Management of these patients is best done with cooperation between the pediatric oncologists, pediatric
surgeons, and pediatric cardiac surgeons. We present 4 cases of retroperitoneal tumors with caval extension as a basis for developing a management strategy for these patients.
1. Case reports Under institutional review board approval (no. 5091), the records of 4 consecutive patients with retroperitoneal tumors and intravascular extension into the IVC were reviewed. Table 1 summarizes each patient and the characteristics of their disease.
1.1. Patient 1 ⁎ Corresponding author. Childrens National Medical Center, 111 Michigan Avenue, NW Washington, DC 20010. Tel.: +1 202 476 2151; fax: +1 202 476 4174. E-mail address: [email protected] (P.C. Guzzetta). 0022-3468/$ – see front matter © 2011 Elsevier Inc. All rights reserved. doi:10.1016/j.jpedsurg.2011.06.041
A 4-year-old previously healthy girl presented to an outside hospital with vomiting and abdominal pain. A computed tomographic (CT) scan and abdominal ultrasound showed a left renal mass measuring 10.4 × 8.9 × 6.7 cm with
2066 Table 1
N. Khozeimeh et al. Characteristics of each patient's disease
Age/sex Diagnosis Extent of caval thrombus PreOp biopsy Neoadjuvant treatment CPB required Pathology
Pathology of thrombus IVC radiation? Follow-up (mo) Patency of IVC Disease relapse Alive
Patient 1
Patient 2
Patient 3
Patient 4
4 y/F Left renal mass Left renal vein to retrohepatic cava Yes—favorable histology Wilms' 6 weeks Regimen DD4A No Favorable histology Wilms'
3 y/F Left renal mass Left renal vein to the hepatic veins Yes—favorable histology Wilms' 10 weeks Regimen DD4a No Favorable histology Wilms'
6 y/F Right adrenal mass Right renal vein to right atrium No
6 y/M Left renal mass Left renal vein to right atrium No
No
6 weeks Regimen DD4a Yes + circulatory arrest Clear cell sarcoma of the kidney
Viable tumor present Yes 17 Thrombosed suprarenal IVC No Yes
Viable tumor present Yes 16 Thrombosed suprarenal IVC No Yes
extension into the left renal vein and retrohepatic vena cava (Fig. 1). Bilateral lower lobe pulmonary metastases were also noted. Percutaneous tumor biopsy at our institution revealed Wilms' tumor with favorable histology. With a diagnosis of clinical stage IV disease, the patient underwent 6 weeks of neoadjuvant chemotherapy with vincristine, dactinomycin, and doxorubicin according to National Wilms' Tumor Study (NWTS) Regimen DD4A [1]. A repeat CT scan after chemotherapy showed the mass had decreased in size (5.2 × 6.3 × 5 cm). However, there was persistent tumor extension into the retrohepatic IVC and near occlusion of the IVC.
Yes Undifferentiated neuroblastoma, unfavorable histology Viable tumor present Yes 11 Patent IVC
Viable tumor present Yes 13 Patent IVC
No Yes
No Yes
The patient was taken to the operating room for a joint procedure between the pediatric surgeons and the pediatric cardiac surgeons. A transesophageal echocardiogram (TEE), done under anesthesia, confirmed that the tumor thrombus extended to the level of the diaphragm but not into the right atrium. The patient underwent laparotomy through a midline incision so that the incision could be extended into the chest. A left nephrectomy was performed. Via a partial lower sternotomy, the intrapericardial IVC was found to be free of tumor, confirming the TEE findings. Control and temporary occlusion of the porta hepatis and suprarenal IVC was obtained. The intrapericardial IVC was then occluded with a vascular clamp without a decrease in blood pressure. A cavotomy and thrombectomy were performed to remove the tumor thrombus completely. The IVC was repaired primarily and intraoperative TEE showed no residual IVC tumor. Histologic examination of the IVC thrombus identified viable tumor. The primary tumor was confirmed to be favorable histology Wilms' tumor. The patient completed 25 weeks of adjuvant chemotherapy, whole lung radiation, and left flank radiation with a boost to the IVC. Postoperative imaging revealed no residual tumor; however, a thrombosed suprarenal IVC was noted.
1.2. Patient 2
Fig. 1 Patient 1 CT showing a left renal mass measuring 10.4 × 8.9 × 6.7 cm with extension into the retrohepatic vena cava.
A 3-year-old previously healthy girl presented with a 2week history of increasing abdominal girth following a fall. A CT scan showed a left renal mass measuring 11.5 × 11.6 × 17.3 cm extending into the left renal vein and retrohepatic vena cava to the hepatic veins (Fig. 2). Multiple pulmonary metastases were also noted. Percutaneous tumor biopsy revealed Wilms' tumor with favorable histology. The patient
Management of retroperitoneal tumor with caval tumors
Fig. 2 Patient 2 CT showing a left renal mass measuring 11.5 × 11.6 × 17.3 cm with extension into the retrohepatic vena cava.
underwent 10 weeks of neoadjuvant chemotherapy of vincristine, dactinomycin, and doxorubicin according to the NWTS Regimen DD4A. A repeat CT scan showed the mass had decreased in size (13.3 × 8.4 × 7.8 cm), but the IVC tumor thrombus was unchanged. The patient was taken to the operating room and a TEE was done under anesthesia. This confirmed extension of the tumor thrombus to the hepatic veins, but not into the right atrium. Through a midline laparotomy incision, so that it could be extended into the chest, the patient underwent a left nephrectomy. Similar to Patient 1, the intrapericardial IVC was accessed by extending the midline laparotomy to a partial lower sternotomy. It was found to be free of tumor, confirming the TEE findings. Control and temporary occlusion of the porta hepatis and suprarenal IVC was obtained. The intrapericardial IVC was then occluded with a vascular clamp without a decrease in blood pressure. A cavotomy and thrombectomy were performed to remove the tumor thrombus completely. Intraoperative TEE showed no residual IVC tumor. Histologic examination of the IVC thrombus identified viable tumor. The primary tumor was confirmed to be favorable histology Wilms' tumor. The patient completed 6 months of adjuvant chemotherapy, whole lung radiation, and left flank radiation. Postoperative imaging showed no evidence of recurrent disease, but the inferior vena cava remained thrombosed from the renal veins to the retrohepatic segment.
2067 intraperitoneal fluid (Fig. 3). The patient was tachycardic, but normotensive. She was also febrile and having significant abdominal and flank pain. Tumor thrombus was seen extending into the IVC and right atrium. Echocardiogram showed a large mobile tumor thrombus occupying almost half the volume of the right atrium. This crossed the tricuspid valve in each diastole. Homovanillic acid and vanillylmandelic acid levels were slightly elevated at 21.4 mg/g (normal 0-15.7) and 17.9 mg/g (0-11.2). Presumptive diagnoses were either an adrenal neuroblastoma or an adrenocortical carcinoma. Pediatric surgery, pediatric cardiology, pediatric oncology and pediatric cardiac surgery met to discuss her treatment plan. It was agreed that the large atrial thrombus posed a serious risk of causing a fatal pulmonary embolus and surgical resection was her best option. A TEE done under anesthesia confirmed that the tumor thrombus extended from the IVC into the right atrium and across the tricuspid valve. Through a long midline incision, access to the chest and abdomen was obtained. Porta hepatis and suprarenal IVC control was obtained without manipulation of the tumor mass before heparinization. Cardiopulmonary bypass (CPB) was instituted by cannulation of the ascending aorta and venous cannulae in the superior vena cava (SVC) and left femoral vein. After snaring of the SVC, a right atriotomy revealed a large, well encapsulated tumor. The mass was seen to be an extension of the intracaval mass, without any intracardiac attachments. The tumor thrombus was dissected caudally into the IVC as far as possible and divided. The right kidney was found to be normal. The adrenal tumor was invading the right adrenal vein and had ruptured into the retroperitoneal space. The intrapericardial dissection had freed the IVC of all tumor except the adrenal vein invasion. This was milked out before ligation of the vein. The patient was weaned off CPB
1.3. Patient 3 A 6-year-old previously healthy girl presented to an outside hospital with abdominal pain after a fall. CT scan showed a right retroperitoneal suprarenal mass measuring 8.2 × 7.7 × 9.6 cm with a surrounding hematoma and
Fig. 3 Patient 3 CT showing a right retroperitoneal mass measuring 8.2 × 7.7 × 9.6 cm with extension into the right atrium.
2068 after completion of the intraabdominal resection. Repeat intraoperative TEE did not reveal any residual intracardiac tumor, although imaging of the retrohepatic IVC was limited because there was not a good acoustic window. Histology revealed undifferentiated neuroblastoma with unfavorable histology according to the Shimada classification system. There was no amplification of the MYCN gene. Because of the extensive manipulation of the IVC, the patient was therapeutically anticoagulated with low molecular weight heparin for 3 months. A follow- up ultrasound and CT scan 2 months postoperatively showed a tumor thrombus measuring 1.8 × 1.4 × 1.0 cm within the ligated right adrenal vein extending into the IVC. Five months postoperatively, a CT scan revealed that the tumor thrombus had resolved and the IVC was patent. Given the patient's age, extent of disease, and unfavorable histology, she was classified as having highrisk neuroblastoma. Postoperatively, she was given six cycles of induction chemotherapy with vincristine, doxorubicin, and cyclophosphamide alternating with cisplatin and etopside. She received consolidation high-dose chemotherapy with autologous stem cell rescue using a melphalan, carboplatin and etopside preparative regimen. She then was given external beam radiation therapy with a field inclusive of the extent of the initial disease which included the whole abdomen and inferior vena cava. Currently, she is 11 months post operation and has begun the final phase of therapy with cis-retinoic and immunotherapy with anti-GD2 antibody, interleukin-2, and granulocyte-monocyte colony stimulating factor.
1.4. Patient 4 A 6-year-old previously healthy boy presented to a hospital in his home country in the Middle East with abdominal pain. On imaging, he was found to have a left renal mass extending into the IVC and right atrium with lung and liver metastases. According to the International Society of Pediatric Oncology (SIOP) protocol guidelines, he was treated for presumed Wilms' tumor with 6 weeks of chemotherapy with vincristine, dactinomycin and doxorubicin without tumor biopsy. Repeat imaging showed no change in the tumor burden and he was transferred to our care. Imaging showed a left renal mass measuring 10.8 × 8.5 × 9.7 cm extending into the left renal vein, IVC, right atrium, and across the tricuspid valve (Fig. 4). Multiple hepatic and pulmonary lesions were also noted. Because of the risk of emboli from the intracardiac tumor extension and the lack of tumor responsiveness to chemotherapy, the patient was taken to the operating room for nephrectomy and tumor thrombus excision. TEE under anesthesia confirmed intracardiac extension of the tumor thrombus. Through a long midline incision, which provided access to the chest and abdomen, porta hepatis and suprarenal IVC control were obtained. CPB was established via ascending aortic and single venous cannulation through
N. Khozeimeh et al.
Fig. 4 Patient 4 CT showing a left renal mass measuring 10.8 × 8.5 × 9.7 cm extending into the inferior vena cava. The arrows highlight the thrombus extension into the vena cava in each figure.
the right atrial appendage, with minimal manipulation of the heart. Deep hypothermic circulatory arrest (DHCA) and exsanguination were instituted and the circulation was stopped. The right atrial cannula was removed and a right atriotomy revealed a large well encapsulated tumor. It was found to be attached to the eustachian valve and had twisted into a spiral shape across the tricuspid valve. After dissection as far caudally into the IVC as possible, the tumor was removed. The atriotomy was closed and CPB resumed. The intrapericardial IVC was controlled with a vascular clamp. During rewarming, while still on CPB, the intraabdominal dissection was completed. An intraabdominal cavotomy was made, the tumor excised, and a left nephrectomy was performed. The left adrenal gland was invaded by tumor and perirenal lymph nodes were obviously enlarged and also resected. Histology revealed clear cell sarcoma of the kidney (CCSK) with lymph node involvement. Viable tumor was also identified in the atrial tumor thrombus. Because of the extensive surgical manipulation of the IVC, the patient was therapeutically anticoagulated with low molecular weight heparin for 3 months. Follow-up imaging at 3 months after surgery revealed a patent vena cava. Postoperatively, the patient received chemotherapy according the Children's Oncology Group AREN0321 protocol with vincristine, doxorubicin, cyclophosphamide alternating with cyclophosphamide, carboplatin, and etoposide. He also received whole lung radiation, flank radiation, and liver radiation. His course was complicated by severe hepatopathy with marked abdominal distention and ascites, necessitating placement of a peritoneal catheter. During this episode, abdominal ultrasound and CT scan revealed a new thrombus below the level of the renal veins. This thrombus
Management of retroperitoneal tumor with caval tumors
2069
was considered to be a result of venous stasis from increased abdominal pressure. Low molecular weight heparin therapy was reinitiated, with near complete resolution of the new thrombus after 2 weeks. At his most recent visit, the patient remained on anticoagulation therapy.
embolism in one patient, tumor progression in one patient, and acute respiratory distress syndrome in 3 patients, one of which was fatal. In patients with Wilms' tumor IVC thrombus, when all types of complications were taken into account, there was no difference in complication rate between the initial surgery group and the neoadjuvant chemotherapy group [2]. Thus, which approach is best should be determined on a case-by-case basis. In Patient 3 of our report, the risk of lethal pulmonary embolus and uncertainty of the histology led us to perform initial resection. In patient 4, initial surgery was performed after the tumor did not respond to chemotherapy, and with the thrombus traversing the tricuspid valve, we believed the child was at high risk for massive pulmonary embolus. In Patients 1 and 2, after histologic confirmation of favorable histology Wilms' tumor, the treatment team elected to proceed with neoadjuvant chemotherapy and then surgery. Concern regarding endothelial adherence of tumor thrombus from preoperative therapy was expressed by deLorimier [16], who found an increased rate of thrombus fibrosis in patients so treated. In the NWTS-4 series, tumor was adherent to the blood vessel in 43.7% of initial surgery cases versus 61.7% of neoadjuvant chemotherapy cases (P = .04) [2]. Viable tumor in intravascular thrombus extensions have been found in 83% of cases in the NWTS-4 study [2] and in all patients in our series. Interestingly, incomplete thrombus resection was not found to be an adverse prognostic factor in the NWTS-4 study, which raises the question of whether heroic surgical attempts to remove all tumor thrombi are necessary. Preoperative identification of caval tumor thrombus in patients with retroperitoneal tumors is imperative to surgical planning. In addition to CT and MRI, Doppler ultrasonography is reliable in identifying the presence and extent of IVC tumor thrombus [17-19]. Pediatric cardiac surgeons have extensive experience with intraoperative TEE and believe it is a valuable adjunct in determining tumor extent, as well as completion of tumor thrombectomy. However, imaging of retrohepatic and lower segments of IVC is limited by TEE, which can miss residual disease as demonstrated in Patient 3. IVC control above the tumor thrombus is essential and can be obtained transperitoneally if the tumor thrombus is infrahepatic. In our experience, retrohepatic or suprahepatic extension is most safely managed by entry into the chest for intrapericardial IVC control as previously described [20]. In the absence of intracardiac extension, suprahepatic IVC control can be done easily via a lower mini-sternotomy (patients 1 and 2). In the event of large, mobile atrial extension, CPB with DHCA is often needed (patient 4), to decrease the risk of tumor embolization and allow complete extraction of the tumor thrombus. In patients with complete occlusion of the IVC and relatively immobile tumor thrombus, DHCA can be avoided by use of SVC and peripheral venous cannulation (Patient 3). Difficult intraabdominal dissection of the IVC thrombus should be done
2. Discussion Intravascular invasion occurs in 3-8% of patients with pediatric renal tumors [2-4] with Wilms' tumor representing 98% of patients with IVC tumor thrombi in the NWTS-4 [2]. Intracaval tumor thrombi may be classified according to the upper extent of the tumor thrombus in relation to the hepatic veins (modified Skinner classification of renal cell carcinoma): level 1, infrahepatic thrombus; level 2, retrohepatic thrombus; and level 3, suprahepatic or atrial thrombus [5,6]. For Patient 3, imaging indicated that the tumor was suprarenal, raising the suspicion of an adrenal tumor. Because urine catecholamines were only mildly elevated, adrenocortical carcinoma and extra-renal Wilms' tumor were considered in addition to neuroblastoma. Pathology revealed neuroblastoma, which very rarely presents with tumor thrombus. In our review of the literature, we found only six cases of neuroblastoma with tumor thrombus and only 2 had atrial extension [7-9]. In patient 4, histology revealed CCSK. Although previously reported in adults [10-12], intravascular extension with CCSK is rare [13], comprising only 2% of cases of tumor thrombus in the NWTS-4 [14]. However, the incidence of tumor thrombus among all cases of CCSK (6%) is similar to the incidence in Wilms' tumor (3-8%) [2,4]. IVC tumor thrombus has also been reported with pediatric renal cell carcinoma and malignant rhabdoid tumor [4]. When confronted with a patient with intravascular tumor extension, the treatment team faces the difficult decision of whether to perform initial surgical resection or to administer neoadjuvant chemotherapy. The SIOP group recommends neoadjuvant chemotherapy for most patients with a presumed diagnosis of Wilms' tumor. The Children's Oncology Group/NWTS studies indicate that in a child with Wilms' tumor and an intracaval thrombus above the level of the hepatic veins, preoperative chemotherapy should be given. This recommendation was based on the observation that most patients experience shrinkage of the tumor thrombus in response to chemotherapy. In some cases, shrinkage can avoid CPB [2]. Surgical complications in patients with intravascular tumor extension treated with initial surgery were as high as 43% in NWTS-3, which decreased to 26% (17.2% with IVC extension; 36.7% with atrial extension) in NWTS-4 [2,15]. Neoadjuvant chemotherapy lowered the complication rate to 13.2%, a difference trending towards statistical significance (P = .053). However, this approach has risks. Five patients receiving neoadjuvant chemotherapy had complications before surgery including pulmonary
2070 while the patient is still on CPB to avoid hemodynamic consequences of severe hemorrhage (patient 3). Based upon the authors' collective experience, we recommend in a patient with a renal tumor and retrohepatic tumor thrombus but without atrial extension, percutaneous tumor biopsy and neoadjuvant chemotherapy should be performed first. If the IVC tumor thrombus persists after neoadjuvant chemotherapy, IVC thrombectomy with intrapericardial IVC, porta hepatis, and suprarenal IVC control should be done at the time of nephrectomy. For large intraatrial tumor thrombi that are at risk for pulmonary embolus, initial surgical therapy is recommended. Postoperatively, patients 1 and 2 were not anticoagulated and their IVC developed occlusive thrombi. Based on this observation and the intimal disruption of the IVC wall that occurs during thrombectomy, we elected to anticoagulate patients 3 and 4 with low molecular weight heparin for 3 months postoperatively. The surgically manipulated portions of the IVC in both of these patients are currently without thrombi. Although we cannot draw firm conclusions regarding the efficacy of anticoagulation after IVC thrombectomy, our experience suggests that anticoagulation should be done unless contraindicated. Despite the surgical challenges associated with retroperitoneal tumors with intravascular extension, the large series from the NWTS, the United Kingdom, and SIOP demonstrated that patients with tumor thrombus have excellent relapse-free and overall survival rates. These results are comparable to patients without thrombus [2-4]. With appropriate imaging, tailored surgical therapy, multidisciplinary involvement, and appropriate postoperative surveillance, operative risks can be minimized and the outcomes favorable for these children.
References [1] Dome JS, Cotton CA, Perlman EJ, et al. Treatment of anaplastic histology Wilms' tumor: Results from the fifth National Wilms' Tumor Study. J Clin Oncol 2006;24:2352-8. [2] Shamberger RC, Ritchey ML, Haase GM, et al. Intravascular extension of Wilms' tumor. Ann Surg 2001;234:116-21.
N. Khozeimeh et al. [3] Lall A, Pritchard-Jones K, Walker J, et al. Wilms' tumor with intracaval thrombus in the UK Children's Cancer Study Group UKW3 trial. J Pediatr Surg 2006;41:382-7. [4] Szavay P, Luithle T, Semler O, et al. Surgery of cavoatrial tumor thrombus in nephroblastoma: A report of the SIOP/SPOH study. Pediatr Blood Cancer 2004;43:40-5. [5] Thompson WR, Newman K, Seibel N, et al. A strategy for resection of Wilm's tumor with vena cava or atrial extension. J Pediatr Surg 1992;27:912-5. [6] Skinner DG, Pritchett TR, Liekovsky G, et al. Vena caval involvement by renal cell carcinoma. Ann Surg 1989;210:387-94. [7] Bagatell R, Morgan E, Cosentino C, et al. Two cases of pediatric neuroblastoma with tumor thrombus in the inferior vena cava. J Pediatr Hematol Oncol 2002;24:397-400. [8] Day DL, Johnson R, Cohen MD. Abdominal neuroblastoma with inferior vena caval thrombus: report of three cases (one with right atrial extension). Pediatr Radiol 1991;21:205-7. [9] Nagda SN, Lo SS, Melian E, et al. Unusual thoracic problems in patients with malignancies: case 1. Neuroblastoma presenting with intracardiac tumor thrombus. J Clin Oncol 2005;23:2856-61. [10] Toyoda Y, Yamashiota C, Sugimoto T, et al. Clear cell sarcoma of the kidney with tumor extension into the right atrium. J Cardiovasc Surg (Torino) 1998;39:489-91. [11] Tsuji Y, Yamashita C, Wakiyama H, et al. Surgical treatment for transvenous tumor extension into the heart: four cases. J Vasc Surg 1998;27:740-4. [12] Bhayani SB, Liapis H, Kibel AS. Adult clear cell sarcoma of the kidney with atrial tumor thrombus. J Urol 2001;165:896-7. [13] Zigman A, Shen I. Clear cell sarcoma of the kidney with cavo-atrial tumor thrombus: complete resection in a child. J Pediatr Surg 2006;41: 1464-6. [14] Argani P, Perlman EJ, Breslow NW, et al. Clear cell sarcoma of the kidney: a review of 351 cases from the National Wilms' Tumor Study group pathology center. Am J Surg Pathol 2000;24:4-18. [15] Nakayama DK, DeLorimier AA, O'Neil Jr JA, et al. Intracardiac extension of Wilms' tumor: a report of the National Wilms' Tumor Study. Ann Surg 1986;204:693-7. [16] DeLorimier AA. Surgical treatment of Wilms' tumor. In: Pochedly C, Miller D, editors. Wilms' tumor. New York, NY: John Wiley and Sons; 1976. p. 167-88. [17] Ritchey ML, Kelalis PP, Breslow N, et al. Intracaval and atrial involvement with nephroblastoma: Review of the National Wilms' Tumor Study 3. J Urol 1988;140:1113-8. [18] Ritchey ML, Kelalis PP, Haase GM, et al. Preoperative therapy for intracaval and atrial extension of Wilms' tumor. Cancer 1993;71: 4104-10. [19] Reimant AH, Siegel MJ, Shackelford GD. Wilms' tumor in children: Abdominal CT and US evaluation. Radiology 1986;160:501-5. [20] Lodge AJ, Jaggers J, Adams D, et al. Vascular control for resection of suprahepatic intracaval Wilms' tumor: Technical considerations. J Pediatr Surg 2000;35:1836-7.
www.elsevier.com/locate/jpedsurg
Strategy for management of retroperitoneal tumors with caval tumor thrombus Nini Khozeimeh a , Pranava Sinha b , Jeffrey S. Dome c , Philip C. Guzzetta Jr a,⁎ a
Department of Pediatric Surgery, Children's National Medical Center, Washington, DC 20010, USA Department of Cardiac Surgery, Children's National Medical Center, Washington, DC 20010, USA c Department of Hematology and Oncology, Children's National Medical Center Washington, DC b
Received 18 March 2011; revised 8 June 2011; accepted 25 June 2011
Key words: Retroperitoneal tumors; Intracaval tumor extension
Abstract The surgical management of retroperitoneal tumors extending into the inferior vena cava (IVC) can be challenging. Although Wilms' tumor is the most common retroperitoneal tumor extending into the IVC, one must approach these tumors systematically as other diagnoses are possible. We present 4 consecutive cases of retroperitoneal tumors with IVC extension as a basis for a management strategy in approaching these patients. Despite similar presentations, these cases illustrate the nuances in surgical management and need for multidisciplinary care with the pediatric oncologists, pediatric surgeons, and pediatric cardiac surgeons. © 2011 Elsevier Inc. All rights reserved.
The management of tumors that extend into the inferior vena cava (IVC) is determined by multiple factors including [1] extent of tumor thrombus, [2] possibility of tumor embolus, [3] tumor histology, [4] responsiveness of the tumor to chemotherapy, and [5] tumor stage at presentation. Imaging studies can accurately delineate the extent of vascular invasion and often suggest the diagnosis of these tumors. Both factors may modify the surgical approach and consideration of the administration of neoadjuvant therapy. Wilms' tumor is the most common retroperitoneal tumor extending into the IVC in a child, but other diagnoses are also possible. One must approach these tumors systematically. Management of these patients is best done with cooperation between the pediatric oncologists, pediatric
surgeons, and pediatric cardiac surgeons. We present 4 cases of retroperitoneal tumors with caval extension as a basis for developing a management strategy for these patients.
1. Case reports Under institutional review board approval (no. 5091), the records of 4 consecutive patients with retroperitoneal tumors and intravascular extension into the IVC were reviewed. Table 1 summarizes each patient and the characteristics of their disease.
1.1. Patient 1 ⁎ Corresponding author. Childrens National Medical Center, 111 Michigan Avenue, NW Washington, DC 20010. Tel.: +1 202 476 2151; fax: +1 202 476 4174. E-mail address: [email protected] (P.C. Guzzetta). 0022-3468/$ – see front matter © 2011 Elsevier Inc. All rights reserved. doi:10.1016/j.jpedsurg.2011.06.041
A 4-year-old previously healthy girl presented to an outside hospital with vomiting and abdominal pain. A computed tomographic (CT) scan and abdominal ultrasound showed a left renal mass measuring 10.4 × 8.9 × 6.7 cm with
2066 Table 1
N. Khozeimeh et al. Characteristics of each patient's disease
Age/sex Diagnosis Extent of caval thrombus PreOp biopsy Neoadjuvant treatment CPB required Pathology
Pathology of thrombus IVC radiation? Follow-up (mo) Patency of IVC Disease relapse Alive
Patient 1
Patient 2
Patient 3
Patient 4
4 y/F Left renal mass Left renal vein to retrohepatic cava Yes—favorable histology Wilms' 6 weeks Regimen DD4A No Favorable histology Wilms'
3 y/F Left renal mass Left renal vein to the hepatic veins Yes—favorable histology Wilms' 10 weeks Regimen DD4a No Favorable histology Wilms'
6 y/F Right adrenal mass Right renal vein to right atrium No
6 y/M Left renal mass Left renal vein to right atrium No
No
6 weeks Regimen DD4a Yes + circulatory arrest Clear cell sarcoma of the kidney
Viable tumor present Yes 17 Thrombosed suprarenal IVC No Yes
Viable tumor present Yes 16 Thrombosed suprarenal IVC No Yes
extension into the left renal vein and retrohepatic vena cava (Fig. 1). Bilateral lower lobe pulmonary metastases were also noted. Percutaneous tumor biopsy at our institution revealed Wilms' tumor with favorable histology. With a diagnosis of clinical stage IV disease, the patient underwent 6 weeks of neoadjuvant chemotherapy with vincristine, dactinomycin, and doxorubicin according to National Wilms' Tumor Study (NWTS) Regimen DD4A [1]. A repeat CT scan after chemotherapy showed the mass had decreased in size (5.2 × 6.3 × 5 cm). However, there was persistent tumor extension into the retrohepatic IVC and near occlusion of the IVC.
Yes Undifferentiated neuroblastoma, unfavorable histology Viable tumor present Yes 11 Patent IVC
Viable tumor present Yes 13 Patent IVC
No Yes
No Yes
The patient was taken to the operating room for a joint procedure between the pediatric surgeons and the pediatric cardiac surgeons. A transesophageal echocardiogram (TEE), done under anesthesia, confirmed that the tumor thrombus extended to the level of the diaphragm but not into the right atrium. The patient underwent laparotomy through a midline incision so that the incision could be extended into the chest. A left nephrectomy was performed. Via a partial lower sternotomy, the intrapericardial IVC was found to be free of tumor, confirming the TEE findings. Control and temporary occlusion of the porta hepatis and suprarenal IVC was obtained. The intrapericardial IVC was then occluded with a vascular clamp without a decrease in blood pressure. A cavotomy and thrombectomy were performed to remove the tumor thrombus completely. The IVC was repaired primarily and intraoperative TEE showed no residual IVC tumor. Histologic examination of the IVC thrombus identified viable tumor. The primary tumor was confirmed to be favorable histology Wilms' tumor. The patient completed 25 weeks of adjuvant chemotherapy, whole lung radiation, and left flank radiation with a boost to the IVC. Postoperative imaging revealed no residual tumor; however, a thrombosed suprarenal IVC was noted.
1.2. Patient 2
Fig. 1 Patient 1 CT showing a left renal mass measuring 10.4 × 8.9 × 6.7 cm with extension into the retrohepatic vena cava.
A 3-year-old previously healthy girl presented with a 2week history of increasing abdominal girth following a fall. A CT scan showed a left renal mass measuring 11.5 × 11.6 × 17.3 cm extending into the left renal vein and retrohepatic vena cava to the hepatic veins (Fig. 2). Multiple pulmonary metastases were also noted. Percutaneous tumor biopsy revealed Wilms' tumor with favorable histology. The patient
Management of retroperitoneal tumor with caval tumors
Fig. 2 Patient 2 CT showing a left renal mass measuring 11.5 × 11.6 × 17.3 cm with extension into the retrohepatic vena cava.
underwent 10 weeks of neoadjuvant chemotherapy of vincristine, dactinomycin, and doxorubicin according to the NWTS Regimen DD4A. A repeat CT scan showed the mass had decreased in size (13.3 × 8.4 × 7.8 cm), but the IVC tumor thrombus was unchanged. The patient was taken to the operating room and a TEE was done under anesthesia. This confirmed extension of the tumor thrombus to the hepatic veins, but not into the right atrium. Through a midline laparotomy incision, so that it could be extended into the chest, the patient underwent a left nephrectomy. Similar to Patient 1, the intrapericardial IVC was accessed by extending the midline laparotomy to a partial lower sternotomy. It was found to be free of tumor, confirming the TEE findings. Control and temporary occlusion of the porta hepatis and suprarenal IVC was obtained. The intrapericardial IVC was then occluded with a vascular clamp without a decrease in blood pressure. A cavotomy and thrombectomy were performed to remove the tumor thrombus completely. Intraoperative TEE showed no residual IVC tumor. Histologic examination of the IVC thrombus identified viable tumor. The primary tumor was confirmed to be favorable histology Wilms' tumor. The patient completed 6 months of adjuvant chemotherapy, whole lung radiation, and left flank radiation. Postoperative imaging showed no evidence of recurrent disease, but the inferior vena cava remained thrombosed from the renal veins to the retrohepatic segment.
2067 intraperitoneal fluid (Fig. 3). The patient was tachycardic, but normotensive. She was also febrile and having significant abdominal and flank pain. Tumor thrombus was seen extending into the IVC and right atrium. Echocardiogram showed a large mobile tumor thrombus occupying almost half the volume of the right atrium. This crossed the tricuspid valve in each diastole. Homovanillic acid and vanillylmandelic acid levels were slightly elevated at 21.4 mg/g (normal 0-15.7) and 17.9 mg/g (0-11.2). Presumptive diagnoses were either an adrenal neuroblastoma or an adrenocortical carcinoma. Pediatric surgery, pediatric cardiology, pediatric oncology and pediatric cardiac surgery met to discuss her treatment plan. It was agreed that the large atrial thrombus posed a serious risk of causing a fatal pulmonary embolus and surgical resection was her best option. A TEE done under anesthesia confirmed that the tumor thrombus extended from the IVC into the right atrium and across the tricuspid valve. Through a long midline incision, access to the chest and abdomen was obtained. Porta hepatis and suprarenal IVC control was obtained without manipulation of the tumor mass before heparinization. Cardiopulmonary bypass (CPB) was instituted by cannulation of the ascending aorta and venous cannulae in the superior vena cava (SVC) and left femoral vein. After snaring of the SVC, a right atriotomy revealed a large, well encapsulated tumor. The mass was seen to be an extension of the intracaval mass, without any intracardiac attachments. The tumor thrombus was dissected caudally into the IVC as far as possible and divided. The right kidney was found to be normal. The adrenal tumor was invading the right adrenal vein and had ruptured into the retroperitoneal space. The intrapericardial dissection had freed the IVC of all tumor except the adrenal vein invasion. This was milked out before ligation of the vein. The patient was weaned off CPB
1.3. Patient 3 A 6-year-old previously healthy girl presented to an outside hospital with abdominal pain after a fall. CT scan showed a right retroperitoneal suprarenal mass measuring 8.2 × 7.7 × 9.6 cm with a surrounding hematoma and
Fig. 3 Patient 3 CT showing a right retroperitoneal mass measuring 8.2 × 7.7 × 9.6 cm with extension into the right atrium.
2068 after completion of the intraabdominal resection. Repeat intraoperative TEE did not reveal any residual intracardiac tumor, although imaging of the retrohepatic IVC was limited because there was not a good acoustic window. Histology revealed undifferentiated neuroblastoma with unfavorable histology according to the Shimada classification system. There was no amplification of the MYCN gene. Because of the extensive manipulation of the IVC, the patient was therapeutically anticoagulated with low molecular weight heparin for 3 months. A follow- up ultrasound and CT scan 2 months postoperatively showed a tumor thrombus measuring 1.8 × 1.4 × 1.0 cm within the ligated right adrenal vein extending into the IVC. Five months postoperatively, a CT scan revealed that the tumor thrombus had resolved and the IVC was patent. Given the patient's age, extent of disease, and unfavorable histology, she was classified as having highrisk neuroblastoma. Postoperatively, she was given six cycles of induction chemotherapy with vincristine, doxorubicin, and cyclophosphamide alternating with cisplatin and etopside. She received consolidation high-dose chemotherapy with autologous stem cell rescue using a melphalan, carboplatin and etopside preparative regimen. She then was given external beam radiation therapy with a field inclusive of the extent of the initial disease which included the whole abdomen and inferior vena cava. Currently, she is 11 months post operation and has begun the final phase of therapy with cis-retinoic and immunotherapy with anti-GD2 antibody, interleukin-2, and granulocyte-monocyte colony stimulating factor.
1.4. Patient 4 A 6-year-old previously healthy boy presented to a hospital in his home country in the Middle East with abdominal pain. On imaging, he was found to have a left renal mass extending into the IVC and right atrium with lung and liver metastases. According to the International Society of Pediatric Oncology (SIOP) protocol guidelines, he was treated for presumed Wilms' tumor with 6 weeks of chemotherapy with vincristine, dactinomycin and doxorubicin without tumor biopsy. Repeat imaging showed no change in the tumor burden and he was transferred to our care. Imaging showed a left renal mass measuring 10.8 × 8.5 × 9.7 cm extending into the left renal vein, IVC, right atrium, and across the tricuspid valve (Fig. 4). Multiple hepatic and pulmonary lesions were also noted. Because of the risk of emboli from the intracardiac tumor extension and the lack of tumor responsiveness to chemotherapy, the patient was taken to the operating room for nephrectomy and tumor thrombus excision. TEE under anesthesia confirmed intracardiac extension of the tumor thrombus. Through a long midline incision, which provided access to the chest and abdomen, porta hepatis and suprarenal IVC control were obtained. CPB was established via ascending aortic and single venous cannulation through
N. Khozeimeh et al.
Fig. 4 Patient 4 CT showing a left renal mass measuring 10.8 × 8.5 × 9.7 cm extending into the inferior vena cava. The arrows highlight the thrombus extension into the vena cava in each figure.
the right atrial appendage, with minimal manipulation of the heart. Deep hypothermic circulatory arrest (DHCA) and exsanguination were instituted and the circulation was stopped. The right atrial cannula was removed and a right atriotomy revealed a large well encapsulated tumor. It was found to be attached to the eustachian valve and had twisted into a spiral shape across the tricuspid valve. After dissection as far caudally into the IVC as possible, the tumor was removed. The atriotomy was closed and CPB resumed. The intrapericardial IVC was controlled with a vascular clamp. During rewarming, while still on CPB, the intraabdominal dissection was completed. An intraabdominal cavotomy was made, the tumor excised, and a left nephrectomy was performed. The left adrenal gland was invaded by tumor and perirenal lymph nodes were obviously enlarged and also resected. Histology revealed clear cell sarcoma of the kidney (CCSK) with lymph node involvement. Viable tumor was also identified in the atrial tumor thrombus. Because of the extensive surgical manipulation of the IVC, the patient was therapeutically anticoagulated with low molecular weight heparin for 3 months. Follow-up imaging at 3 months after surgery revealed a patent vena cava. Postoperatively, the patient received chemotherapy according the Children's Oncology Group AREN0321 protocol with vincristine, doxorubicin, cyclophosphamide alternating with cyclophosphamide, carboplatin, and etoposide. He also received whole lung radiation, flank radiation, and liver radiation. His course was complicated by severe hepatopathy with marked abdominal distention and ascites, necessitating placement of a peritoneal catheter. During this episode, abdominal ultrasound and CT scan revealed a new thrombus below the level of the renal veins. This thrombus
Management of retroperitoneal tumor with caval tumors
2069
was considered to be a result of venous stasis from increased abdominal pressure. Low molecular weight heparin therapy was reinitiated, with near complete resolution of the new thrombus after 2 weeks. At his most recent visit, the patient remained on anticoagulation therapy.
embolism in one patient, tumor progression in one patient, and acute respiratory distress syndrome in 3 patients, one of which was fatal. In patients with Wilms' tumor IVC thrombus, when all types of complications were taken into account, there was no difference in complication rate between the initial surgery group and the neoadjuvant chemotherapy group [2]. Thus, which approach is best should be determined on a case-by-case basis. In Patient 3 of our report, the risk of lethal pulmonary embolus and uncertainty of the histology led us to perform initial resection. In patient 4, initial surgery was performed after the tumor did not respond to chemotherapy, and with the thrombus traversing the tricuspid valve, we believed the child was at high risk for massive pulmonary embolus. In Patients 1 and 2, after histologic confirmation of favorable histology Wilms' tumor, the treatment team elected to proceed with neoadjuvant chemotherapy and then surgery. Concern regarding endothelial adherence of tumor thrombus from preoperative therapy was expressed by deLorimier [16], who found an increased rate of thrombus fibrosis in patients so treated. In the NWTS-4 series, tumor was adherent to the blood vessel in 43.7% of initial surgery cases versus 61.7% of neoadjuvant chemotherapy cases (P = .04) [2]. Viable tumor in intravascular thrombus extensions have been found in 83% of cases in the NWTS-4 study [2] and in all patients in our series. Interestingly, incomplete thrombus resection was not found to be an adverse prognostic factor in the NWTS-4 study, which raises the question of whether heroic surgical attempts to remove all tumor thrombi are necessary. Preoperative identification of caval tumor thrombus in patients with retroperitoneal tumors is imperative to surgical planning. In addition to CT and MRI, Doppler ultrasonography is reliable in identifying the presence and extent of IVC tumor thrombus [17-19]. Pediatric cardiac surgeons have extensive experience with intraoperative TEE and believe it is a valuable adjunct in determining tumor extent, as well as completion of tumor thrombectomy. However, imaging of retrohepatic and lower segments of IVC is limited by TEE, which can miss residual disease as demonstrated in Patient 3. IVC control above the tumor thrombus is essential and can be obtained transperitoneally if the tumor thrombus is infrahepatic. In our experience, retrohepatic or suprahepatic extension is most safely managed by entry into the chest for intrapericardial IVC control as previously described [20]. In the absence of intracardiac extension, suprahepatic IVC control can be done easily via a lower mini-sternotomy (patients 1 and 2). In the event of large, mobile atrial extension, CPB with DHCA is often needed (patient 4), to decrease the risk of tumor embolization and allow complete extraction of the tumor thrombus. In patients with complete occlusion of the IVC and relatively immobile tumor thrombus, DHCA can be avoided by use of SVC and peripheral venous cannulation (Patient 3). Difficult intraabdominal dissection of the IVC thrombus should be done
2. Discussion Intravascular invasion occurs in 3-8% of patients with pediatric renal tumors [2-4] with Wilms' tumor representing 98% of patients with IVC tumor thrombi in the NWTS-4 [2]. Intracaval tumor thrombi may be classified according to the upper extent of the tumor thrombus in relation to the hepatic veins (modified Skinner classification of renal cell carcinoma): level 1, infrahepatic thrombus; level 2, retrohepatic thrombus; and level 3, suprahepatic or atrial thrombus [5,6]. For Patient 3, imaging indicated that the tumor was suprarenal, raising the suspicion of an adrenal tumor. Because urine catecholamines were only mildly elevated, adrenocortical carcinoma and extra-renal Wilms' tumor were considered in addition to neuroblastoma. Pathology revealed neuroblastoma, which very rarely presents with tumor thrombus. In our review of the literature, we found only six cases of neuroblastoma with tumor thrombus and only 2 had atrial extension [7-9]. In patient 4, histology revealed CCSK. Although previously reported in adults [10-12], intravascular extension with CCSK is rare [13], comprising only 2% of cases of tumor thrombus in the NWTS-4 [14]. However, the incidence of tumor thrombus among all cases of CCSK (6%) is similar to the incidence in Wilms' tumor (3-8%) [2,4]. IVC tumor thrombus has also been reported with pediatric renal cell carcinoma and malignant rhabdoid tumor [4]. When confronted with a patient with intravascular tumor extension, the treatment team faces the difficult decision of whether to perform initial surgical resection or to administer neoadjuvant chemotherapy. The SIOP group recommends neoadjuvant chemotherapy for most patients with a presumed diagnosis of Wilms' tumor. The Children's Oncology Group/NWTS studies indicate that in a child with Wilms' tumor and an intracaval thrombus above the level of the hepatic veins, preoperative chemotherapy should be given. This recommendation was based on the observation that most patients experience shrinkage of the tumor thrombus in response to chemotherapy. In some cases, shrinkage can avoid CPB [2]. Surgical complications in patients with intravascular tumor extension treated with initial surgery were as high as 43% in NWTS-3, which decreased to 26% (17.2% with IVC extension; 36.7% with atrial extension) in NWTS-4 [2,15]. Neoadjuvant chemotherapy lowered the complication rate to 13.2%, a difference trending towards statistical significance (P = .053). However, this approach has risks. Five patients receiving neoadjuvant chemotherapy had complications before surgery including pulmonary
2070 while the patient is still on CPB to avoid hemodynamic consequences of severe hemorrhage (patient 3). Based upon the authors' collective experience, we recommend in a patient with a renal tumor and retrohepatic tumor thrombus but without atrial extension, percutaneous tumor biopsy and neoadjuvant chemotherapy should be performed first. If the IVC tumor thrombus persists after neoadjuvant chemotherapy, IVC thrombectomy with intrapericardial IVC, porta hepatis, and suprarenal IVC control should be done at the time of nephrectomy. For large intraatrial tumor thrombi that are at risk for pulmonary embolus, initial surgical therapy is recommended. Postoperatively, patients 1 and 2 were not anticoagulated and their IVC developed occlusive thrombi. Based on this observation and the intimal disruption of the IVC wall that occurs during thrombectomy, we elected to anticoagulate patients 3 and 4 with low molecular weight heparin for 3 months postoperatively. The surgically manipulated portions of the IVC in both of these patients are currently without thrombi. Although we cannot draw firm conclusions regarding the efficacy of anticoagulation after IVC thrombectomy, our experience suggests that anticoagulation should be done unless contraindicated. Despite the surgical challenges associated with retroperitoneal tumors with intravascular extension, the large series from the NWTS, the United Kingdom, and SIOP demonstrated that patients with tumor thrombus have excellent relapse-free and overall survival rates. These results are comparable to patients without thrombus [2-4]. With appropriate imaging, tailored surgical therapy, multidisciplinary involvement, and appropriate postoperative surveillance, operative risks can be minimized and the outcomes favorable for these children.
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N. Khozeimeh et al. [3] Lall A, Pritchard-Jones K, Walker J, et al. Wilms' tumor with intracaval thrombus in the UK Children's Cancer Study Group UKW3 trial. J Pediatr Surg 2006;41:382-7. [4] Szavay P, Luithle T, Semler O, et al. Surgery of cavoatrial tumor thrombus in nephroblastoma: A report of the SIOP/SPOH study. Pediatr Blood Cancer 2004;43:40-5. [5] Thompson WR, Newman K, Seibel N, et al. A strategy for resection of Wilm's tumor with vena cava or atrial extension. J Pediatr Surg 1992;27:912-5. [6] Skinner DG, Pritchett TR, Liekovsky G, et al. Vena caval involvement by renal cell carcinoma. Ann Surg 1989;210:387-94. [7] Bagatell R, Morgan E, Cosentino C, et al. Two cases of pediatric neuroblastoma with tumor thrombus in the inferior vena cava. J Pediatr Hematol Oncol 2002;24:397-400. [8] Day DL, Johnson R, Cohen MD. Abdominal neuroblastoma with inferior vena caval thrombus: report of three cases (one with right atrial extension). Pediatr Radiol 1991;21:205-7. [9] Nagda SN, Lo SS, Melian E, et al. Unusual thoracic problems in patients with malignancies: case 1. Neuroblastoma presenting with intracardiac tumor thrombus. J Clin Oncol 2005;23:2856-61. [10] Toyoda Y, Yamashiota C, Sugimoto T, et al. Clear cell sarcoma of the kidney with tumor extension into the right atrium. J Cardiovasc Surg (Torino) 1998;39:489-91. [11] Tsuji Y, Yamashita C, Wakiyama H, et al. Surgical treatment for transvenous tumor extension into the heart: four cases. J Vasc Surg 1998;27:740-4. [12] Bhayani SB, Liapis H, Kibel AS. Adult clear cell sarcoma of the kidney with atrial tumor thrombus. J Urol 2001;165:896-7. [13] Zigman A, Shen I. Clear cell sarcoma of the kidney with cavo-atrial tumor thrombus: complete resection in a child. J Pediatr Surg 2006;41: 1464-6. [14] Argani P, Perlman EJ, Breslow NW, et al. Clear cell sarcoma of the kidney: a review of 351 cases from the National Wilms' Tumor Study group pathology center. Am J Surg Pathol 2000;24:4-18. [15] Nakayama DK, DeLorimier AA, O'Neil Jr JA, et al. Intracardiac extension of Wilms' tumor: a report of the National Wilms' Tumor Study. Ann Surg 1986;204:693-7. [16] DeLorimier AA. Surgical treatment of Wilms' tumor. In: Pochedly C, Miller D, editors. Wilms' tumor. New York, NY: John Wiley and Sons; 1976. p. 167-88. [17] Ritchey ML, Kelalis PP, Breslow N, et al. Intracaval and atrial involvement with nephroblastoma: Review of the National Wilms' Tumor Study 3. J Urol 1988;140:1113-8. [18] Ritchey ML, Kelalis PP, Haase GM, et al. Preoperative therapy for intracaval and atrial extension of Wilms' tumor. Cancer 1993;71: 4104-10. [19] Reimant AH, Siegel MJ, Shackelford GD. Wilms' tumor in children: Abdominal CT and US evaluation. Radiology 1986;160:501-5. [20] Lodge AJ, Jaggers J, Adams D, et al. Vascular control for resection of suprahepatic intracaval Wilms' tumor: Technical considerations. J Pediatr Surg 2000;35:1836-7.