Venous invasion in renal cell carcinoma: A correlative clinical and radiologic study

Angiography, cavography, ultrasound (US), computed tomography (CT), and low-field magnetic resonance imaging (MRI) were used to explore venous tumor invasion in 86 patients with renal cell carcinoma. The findings confirm previous experience that ultrasound and dynamic CT are reliable methods for the evaluation of venous invasion. Low-field magnetic resonance imaging does not improve tumor staging. In case of equivocal findings, vena cavography should be used as a complementary examination.     

Venous invasion in renal cell carcinoma: a correlative clinical and radiologic study

Angiography, cavography, ultrasound (US), computed tomography (CT), and low-field magnetic resonance imaging (MRI) were used to explore venous tumor invasion in 86 patients with renal cell carcinoma. The findings confirm previous experience that ultrasound and dynamic CT are reliable methods for the evaluation of venous invasion. Low-field magnetic resonance imaging does not improve tumor staging. In case of equivocal findings, vena cavography should be used as a complementary examination.     

Imaging of fat thrombus in the inferior vena cava originating from an angiomyolipoma

A rare case of fat thrombus in the inferior vena cava originating from an angiomyolipoma is reported. Diagnostic imaging including ultrasonography, CT, MRI, and cavography was performed preoperatively. MRI allowed the most complete preoperative staging because of specific fatty signal intensity and good assessment of renal vein involvement.     

Imaging of solid renal masses

Detection of renal cell carcinoma is still a major task for the radiologist. Ultrasonography has replaced excretory urography as the most cost-effective means of detecting early renal cell carcinoma. Detection of small tumors confined to the renal parenchyma has made partial nephrectomy a safe therapeutic alternative, but a longer life expectancy has not been proved. Doppler ultrasonography and MR imaging are used to help distinguish between benign and malignant renal tumors with initial equivocal results. However, accurate diagnostic criteria for CT have been developed and CT remains the standard diagnostic method for characterizing and staging renal tumors. MR imaging has one major advantage: it depicts the degree of tumor involvement of the renal vein and inferior vena cava. Percutaneous fine-needle aspiration biopsy is still important for discriminating between benign and malignant tumors as well as enlarged lymph nodes.     

Magnetic resonance imaging in the staging of renal cell carcinoma

A prospective study has been carried out to examine the role of magnetic resonance imaging (MRI) in the investigation of renal cell carcinoma in 24 patients. In all cases the inferior vena cava (IVC) was well demonstrated with MRI. In 14 out of 15 patients where surgical correlation was available, the MRI and operative staging were in agreement. Magnetic resonance imaging and computed tomographic (CT) staging were in agreement in 16 out of the 17 patients where both were performed. In one case, CT suggested hepatic invasion but this was found not to be present on MRI and at operation. Magnetic resonance imaging also provided substantial additional information in three patients, including two cases where MRI demonstrated a patent IVC that appeared occluded on CT (one of which also had vertebral metastases seen on MRI but missed on CT) and one case where CT failed to demonstrate minimal involvement of the IVC. Magnetic resonance imaging is an accurate means of staging renal cell carcinoma with clear advantages over CT. In no case in this series was inferior vena cavography found to be necessary.     

Clinical staging of malignant tumors by the TNM system. Contribution of modern imaging procedures in patients with testicular tumors

For classification of testicular tumors in the TNM-System several modern imaging methods are available: sonography, conventional radiography, lymphography, computer-tomography, nuclear magnetic resonance and scintigraphy. Sonography--usually the first method to be used for reasonable classification--is significantly inferior to lymphography and CT for N and M staging. It remains to be seen if the NMR-methods will reach the good informative standard of CT. Only in the case of extensive lymphatic metastasis (bulky disease) are i.v. pyelogram and cavography still used to verify displacement of the ureter or infiltration of the tumor into the cava. In the nuclear medical field bone scintigraphy plays the main role for testicular tumor metastases.     

Digital subtraction angiography in the preoperative evaluation of patients with a renal tumor

Inguinal intravenous digital subtraction angiography (DSA) was performed in 14 patients referred for preoperative evaluation of a renal tumor previously diagnosed by CT and ultrasound. Conventional cavography and aortography were used as reference methods for comparison. Both DSA and conventional angiography were carried out following selective arterial injection to the abnormal kidney. The diagnostic value of DSA in examination of the inferior vena cava was generally comparable to that of conventional cavography. Intravenous aortography was unsuccessful in 2 patients due to motion artifacts. In all other patients, the information provided by DSA regarding the aorta, renal arteries and renal veins was similar to that of conventional aortography. Intrarenal vascular detail, however, was far superior on conventional films and was only useful with DSA when intra-arterial injection was implemented. In one of the 12 diagnostic examinations, localization of the renal mass could not be established by intravenous DSA, but was possible in all others. The inguinal approach advocated permits simultaneous inferior vena cavography and intravenous aortography with one single injection of contrast medium; the method is less traumatic than aortography , and does not require hospitalization of the patient. DSA may also be of value in those cases still requiring selective catheterization of the renal arteries, i.e. for angiotherapy . Intra-arterial DSA then allows reduction of the amount of contrast medium and a rapid processing of the images without detriment to the quality of the examination.     

肾盂癌19例CT诊断临床分析

目的探讨CT检查对肾盂癌的诊断价值。方法回顾性分析经CT检查及手术病理证实的19例肾盂癌患者的CT表现和临床资料。结果根据CT表现分为肾盂内肿块型10例,肿块浸润型6例,肾盂壁厚型3例;CT分期为Ⅰ～Ⅱ期8例,Ⅲ期7例,Ⅳ期4例。结论 CT检查在肾盂癌的诊断及鉴别诊断中有一定的价值,是诊断肾盂癌的主要检查方法。     

Percutaneous aspiration of retroperitoneal lymph nodes in ovarian cancer

Nine percutaneous lymph node aspirations were performed on six patients with ovarian carcinoma. Two aspirations were performed for initial staging, while seven were done as part of the restaging evaluation. Seven of the aspirations were positive for tumor. Two aspirations were negative, one of which was surgically confirmed. In five instances the percutaneous aspiration saved the patient an operative procedure. Percutaneous lymph node aspiration is valuable when tissue is required to confirm metastatic disease during staging evaluation, especially with equivocal or atypical lymphograms. The procedure is also useful in assessing abnormal lymphograms that persist after therapy.     

Vena cavography with CO(2) versus with iodinated contrast material for inferior vena cava filter placement: a prospective evaluation

PURPOSE: To determine whether carbon dioxide (CO(2)) vena cavography can safely guide the placement of inferior vena cava (IVC) filters. MATERIALS AND METHODS: One hundred nineteen patients were prospectively enrolled in this study. CO(2 )cavograms were obtained and evaluated for IVC diameter, location of renal veins, and presence of thrombus and venous anomalies. If CO(2 )cavography was judged to be adequate, an IVC filter was deployed. After filter placement, cavography was performed with iodinated contrast material; these images were compared with the CO(2) cavograms. RESULTS: Two patients experienced mild side effects related to venous CO(2) injection. Comparison of cavograms obtained with CO(2) and iodinated contrast-enhanced material showed the caval size to be within 3 mm in all 119 patients. In 116 patients (97.5%), CO(2) cavography was judged to be adequate, and in 115 patients, filters were placed. In three (2.5%) patients, it was necessary to perform iodinated contrast-enhanced cavography before filter deployment. All six cases of venous anomaly and 11 (78.6%) of 14 cases of thrombosis were clearly identified with CO(2) cavography. One filter was maldeployed owing to misinterpretation of the CO(2) cavogram. CONCLUSION: CO(2) cavography is well tolerated, safe, and adequate for identification of the parameters necessary for filter deployment. It is especially valuable in patients with a history of reaction to iodinated contrast material or renal insufficiency.     

Gadolinium-based contrast agents as an alternative at vena cavography in patients with renal insufficiency--early experience.

The authors reviewed results of digital subtraction vena cavography with a gadolinium-based contrast agent in 14 patients with serum creatinine levels greater than or equal to 1.5 mg/dL (133 mumol/L). All cavograms were diagnostic. In 11 patients, there was no impairment of renal function. In three patients, a rise in serum creatinine level of greater than or equal to 0.5 mg/dL (44 mumol/L) was attributable to concurrent medical problems. Gadolinium-based contrast agents may be suitable for digital subtraction vena cavography in patients with renal insufficiency.     

Renal carcinoma: detection of venous extension with gradient-echo MR imaging.

Magnetic resonance (MR) imaging has been proposed as a noninvasive alternative to vena cavography and computed tomography for the detection of venous extension of renal adenocarcinoma. However, spin-echo MR images may be compromised by the presence of flow-related artifacts, extrinsic compression, and respiratory or cardiac motion artifacts. Use of gradient-recalled echo (GRE) sequences is advantageous for imaging of vascular structures. To investigate the detection of vascular extension of tumor with the GRE technique, findings in the preoperative GRE MR images of 26 patients with renal adenocarcinoma were compared with findings at surgery and pathologic examination. Vena cava thrombus was correctly identified in 13 of 13 patients (100%). Renal vein thrombus was correctly identified in 23 of 26 patients (88%), and right atrial thrombus was correctly identified in four of five patients (80%). Use of GRE sequences allows accurate assessment of vascular structures that is sufficient for surgical planning.     

Renal adenocarcinoma: CT staging of 100 tumors

The preoperative CT scans of 100 pathologically proven renal adenocarcinomas were retrospectively reviewed to assess the accuracy of CT for staging the tumor. Regardless of tumor stage, perinephric extension was assessed with a sensitivity of 46% and a specificity of 98%. The sensitivity of CT in detecting venous invasion (either venous enlargement or thrombus) was 78%, with a specificity of 96%. For detection of metastatic adenopathy, CT had a sensitivity of 83% and specificity of 88%. Adjacent organ invasion was correctly identified in 60% of patients, with a specificity of 100%. Overall, CT correctly staged 91% of patients. If errors associated with perinephric invasion were excluded, CT staging accuracy improved to 96%. CT is useful in staging renal adenocarcinoma. If the renal vein is not well seen, angiography or sonography may be necessary to determine the presence of venous tumor extension.     

Magnetic resonance imaging in the diagnosis and staging of renal and perirenal neoplasms

Thirty-one adult patients underwent magnetic resonance (MR) imaging after CT scans had demonstrated findings consistent with renal cell carcinoma. MR images were interpreted prospectively and independently of the CT findings. Because the CT scanning was performed at multiple institutions by many examiners, this study was not a direct comparison of CT versus MR. The preoperative diagnoses and staging of the neoplasms, as judged by MR, were compared with those obtained at laparotomy (n = 28), autopsy (n = 1), or biopsy (n = 2). Correct preoperative diagnoses were rendered in 31 patients (100%) on the basis of MR findings. The anatomic staging of 27 renal cell carcinomas was correctly performed by MR in 26 patients (86%). When compared with results of previous studies of the value of CT in the diagnosis and staging of renal neoplasms, MR appears to have several advantages in determination of the origin of the mass; the evaluation of vascular patency; the detection of perihilar lymph node metastases; and the evaluation of direct tumor invasion of adjacent organs. MR is sensitive in determining the extent of tumor thrombus and in evaluating invasion of the inferior vena caval wall. MR should assume an important role in the diagnosis and staging of renal neoplasms.     

Detection and staging of renal neoplasms: a reassessment of MR imaging

The use of magnetic resonance (MR) imaging in the detection and staging of renal neoplasms was investigated in 104 patients with 106 renal cell carcinomas confirmed at surgery or autopsy. Overall, MR imaging demonstrated 101 of 106 lesions (95%), including all 93 tumors that were larger than 3 cm in diameter but only eight of the 13 smaller tumors (62%). MR imaging enabled accurate staging of 82% of all detected lesions but led to the understaging of nine lesions and the overstaging of nine. At present, MR imaging cannot be used as a screening modality for renal tumors. However, its negative predictive values of 98% and 99%, respectively, for the evaluation of tumor vascular extension and tumor spread to adjacent structures makes it an excellent staging modality that should be used when the CT findings are equivocal. MR imaging is not accurate in indicating bowel and mesentery involvement, but rapid technical advances and the introduction of bowel contrast medium may improve this present limitation.     

Intracaval extension of renal cell carcinoma

Intravenous extension occurs in many patients with renal cell carcinoma. Preoperative recognition is essential as venous involvement alters the surgical approach and clinical staging of the tumors. The venous extension of tumor has a characteristic arteriographic appearance, the recognition of which should prompt venacavography. Computerized body tomography (CBT) may also detect renal vein and caval extension and provide evidence of early ascites from the Budd Chiari syndrome associated with hepatic vein obstruction from intracaval tumor extension. However, it may be difficult to distinguish intracaval blood clot and tumor on the basis of CBT criteria alone. Of the four patients with intracaval growth of renal cell carcinoma, three received preoperative therapeutic tumor embolization, a procedure that carried no additional risk of tumor detachment and embolization.     

Urographic signs of thrombosis of the inferior vena cava and renal veins

The case history of a 39 year old male with abdominal pain is described. Intravenous urography showed, during the late vascular period, collateral venous drainage around kidneys. Bilateral venous impressions on the ureters were observed at the excretory time. Inferior vena cavography and venous phase of selective renal arteriography confirmed the expected diagnosis of inferior vena cava thrombosis with bilateral renal vein involvement. Urographic signs of inferior vena cava thrombosis are discussed.     

正电子放射性核素显像在肾癌诊断中的研究进展

肾细胞癌（RCC）是最常见的肾脏恶性肿瘤，其分期和分型对患者的治疗和生存有重要影响，对原发肿瘤和转移部位的早期检测和准确定位是临床诊疗的关键需求。笔者就正电子放射性核素显像在RCC分期和分型、转移性RCC的检测以及RCC治疗疗效的监测等方面的应用和进展作简要综述。     

Asymptomatic leiomyosarcoma of the inferior vena cava. Incidental finding at ultrasonography

A case of leiomyosarcoma of the inferior vena cava is presented. The tumor was incidentally found at ultrasonography of a patient who underwent a follow-up examination after surgery for carcinoma of the colon. The tumor was resected and the patient was alive and well one year postoperatively at which time repeat ultrasonography and inferior vena cavography showed no remaining tumor.     

Diagnostic accuracy of staging renal cell carcinomas using multidetector-row computed tomography and magnetic resonance imaging: a prospective study with histopathologic correlation

OBJECTIVE: The aim of this prospective study is to compare the diagnostic accuracy of multidetector-row computed tomography (CT) and magnetic resonance imaging (MRI) in tumor staging of renal cell carcinomas. METHODS: In a prospective study, 82 renal cell carcinomas were assessed for tumor staging before surgery using multidetector-row CT and MRI, the results of which were then correlated to histopathologic staging. Triphasic CT (noncontrast, arterial phase, and parenchymal phase) imaging was performed using multidetector-row CT with a reconstructed slice thickness of 2 mm. In MRI, a transverse T1-weighted gradient echo sequence with and without administration of Gd-DTPA, a transverse T2-weighted respiratory-gated turbo spin echo (TSE) sequence, and a coronal T1-weighted gradient echo sequence with Gd-DTPA were used. In addition, multiphasic 3-dimensional angiography after Gd-DTPA injection and a transverse T1-weighted fat-suppression sequence were performed. RESULTS: With MRI, readers 1 and 2 correctly staged 71 and 64 tumors (overall accuracy of 0.87 and 0.78, respectively) and achieved Mantel-Haenszel chi(2) values of 66 and 63 (P < 0.0001). Computed tomography allowed correct staging of 68 and 66 tumors (readers 1 and 2, overall accuracy of 0.83 and 0.80, respectively) with Mantel-Haenszel chi(2) values of 54 and 54 for CT staging (P < 0.0001). No statistically significant difference between overall accuracy was found in the chi(2) test (P > 0.15). CONCLUSION: Magnetic resonance imaging and multidetector-row CT with its multiplanar reconstruction capabilities achieve similar accuracy in tumor staging of renal cell carcinomas.