Comparative value of ultrasonography, computerized tomography, angiography and excretory urography in the staging of renal cell carcinoma

Imaging renal cell carcinoma with ultrasonography, CT and MRI

The increased use of abdominal imaging techniques for a variety of indications has contributed to more-frequent detection of renal cell carcinoma (RCC). Ultrasonography has been used to characterize the solid versus cystic nature of renal masses. This modality has limitations, however, in further characterization of solid tumors and in staging of malignancy, although contrast-enhanced ultrasonography has shown promise. Cross-sectional imaging with multiplanar reconstruction capability via CT or MRI has become the standard-bearer in the diagnosis, staging and surveillance of renal cancers. The use of specific protocols and the exploitation of different imaging characteristics of RCC subtypes, including variations in contrast agent timing, MRI weighting and digital subtraction, have contributed to this diagnostic capability. Cystic renal masses are a special case, evaluation of which can require multiple imaging modalities. Rigorous evaluation of these lesions can provide information that is crucial to prediction of the likelihood of malignancy. Such imaging is not without risk, however, as radiation from frequent CT imaging has been implicated in the development of secondary malignancies, and contrast agents for CT and MRI can pose risks, particularly in patients with compromised renal function.

Renal cell carcinoma: diagnosis, staging, and surveillance

OBJECTIVE

This educational review focuses on the staging and radiologic evaluation of renal cell carcinoma. It includes discussion of the epidemiology, pathology, and therapeutic options of renal cell carcinoma and the implications for radiologic follow-up.

CONCLUSION

The incidence of renal cell carcinoma has been increasing. Imaging plays a central role in its detection, staging, and treatment evaluation and follow-up.

Imaging approach to staging of renal cell carcinoma

Current imaging techniques, especially CT and MR imaging, make accurate preoperative staging of renal cell carcinoma possible. Because surgery provides the only effective therapy and because survival depends on local and distant extent, precise staging is critical for preoperative planning and prognosis. This article reviews the advantages, limitations, accuracy, and pitfalls of each of the imaging approaches to staging renal cell carcinoma, concentrating on CT and MR imaging. This information then is summarized in a suggested overall approach to staging renal cell carcinoma.

Comparative study of cystic variations of the kidneys in haemodialysis and continuous ambulatory peritoneal dialysis patients

In recent years, many complications of renal cell carcinoma accompanying the increase in the number of peritoneal dialysis cases have been studied more often. Clinicopathologically, we studied comparatively cystic changes of the kidney, considered to be a background factor of cancerous development in 69 patients on peritoneal dialysis without past history of haemodialysis and in 192 patients on long-term haemodialysis. From the results, differences with respect to the duration of dialysis until the development of cysts and primary diseases commonly associated with cysts were not found between the two groups. Moreover, in the extirpated kidneys examined for cancerous development, cysts were found in both the peritoneal dialysis and the haemodialysis cases, and proliferative changes were found in the cystic epithelium. A relationship between cystic and cancerous development in the peritoneal dialysis cases was strongly suggested by these findings. Therefore, it was considered that careful follow-up studies for complications such as renal cell carcinoma would be necessary in both the peritoneal dialysis and the haemodialysis cases.

The utility of transesophageal echocardiography in the management of renal cell carcinoma with intracardiac extension

The accurate assessment of the distal extent of vena caval invasion of renal cell carcinoma into the hepatic veins, inferior vena cava, and right atrium is critical before surgical resection. We present two cases of renal carcinoma with vena caval extension in which preoperative transesophageal echocardiography accurately assessed tumor extent and guided surgical therapy. The role of transesophageal echocardiography in comparison to other diagnostic modalities is discussed.

Intraoperative ultrasound in the evaluation of tumor involvement of the inferior vena cava

The successful excision of genitourinary malignancies extending to the inferior vena cava relies heavily on accurate preoperative imaging. For the majority of these patients magnetic resonance imaging, inferior venacavography, abdominal ultrasound or abdominal computerized tomography will reliably predict the extent of inferior vena caval involvement by tumor. However, occasionally the results of these studies will conflict or be called into question intraoperatively. We report on 8 patients considered to be at risk for inferior vena caval involvement by tumor and for whom intraoperative ultrasound was obtained to clarify the presence or extent of thrombus. Five patients had renal cell carcinoma and 3 had adrenal carcinoma. In all patients concern as to the extent or presence of tumor was based on either inconclusive preoperative studies or unexpected intraoperative findings. In each case intraoperative ultrasound clearly visualized the inferior vena cava and established the presence or extent of tumor invasion. In 4 patients venacavotomy was avoided as a consequence of these findings. Intraoperative ultrasound is a useful tool that can accurately assess the inferior vena cava for possible tumor invasion, especially when the presence or extent of tumor involvement is not definitively established preoperatively.

Analysis of imaging modalities, staging systems, and prognostic indicators for renal cell carcinoma

A retrospective analysis of 314 patients with renal cell carcinoma was done focusing mainly on imaging modalities and prognostic significance of tumor stage using both the Robson and TNM systems. Computerized tomography (CT) scan proved to be the most effective modality for staging. Overall staging accuracy was 62 and 68 percent for TNM and Robson staging, respectively, and understaging was more frequent than overstaging. The actuarial five-year survival using the Robson system was 73 percent for Stage A, 68 percent Stage B, 51 percent Stage C, and 20 percent Stage D. The main limitation of the Robson system is the heterogeneity of the Stage C group which includes patients with renal vein and those with nodal involvement with a significant difference in survival. The survival by the TNM system showed no difference in those with T1, T2, T3a and T3b disease but a significant difference in those with T3c or T4a. One hundred sixteen patients (37%) presented with metastatic disease with a median survival of seventeen months (range 2-204) for those with solitary metastasis and six months (range 1-132) for those with multiple metastases (the difference was not statistically significant). Except for anecdotal cases, nephrectomy with or without treatment of the metastases did not seem to affect survival significantly. The presence of spindle cell, alone or in association with clear or granular cell, affected the prognosis adversely. Thirty-one patients had their tumors identified incidentally. Their stage at diagnosis was earlier than the symptomatic group (Stage T1-T2: 77% vs 34%), and there was a significant difference in the disease-free survival at fifty-four months between the two groups (79% vs 57%, respectively).

Accuracy in staging of renal cell carcinoma involving vena cava

Accurate preoperative staging of renal cell carcinoma is necessary to determine patient prognosis and surgical approach, particularly when tumor thrombus invades the vena cava. The pathologically-confirmed tumor stage was compared with the radiographic preoperative stage in 44 patients undergoing surgery for renal cell carcinoma invading the vena cava (T3cNxMx). Nine patients (20%) were upstaged as the result of extracapsular tumor extension. Twelve patients (27%) were upstaged due to unrecognized regional lymphadenopathy, and 1 patient was downstaged. Only 1 patient was upstaged as the result of unrecognized metastases. The level of tumor thrombus extension for surgical approach was accurately determined in all but 2 patients. Overall, 15 patients (34%) were upstaged as a result of pathologic studies, 28 patients (64%) were correctly staged, and 1 patient was downstaged. Radiographic staging of extracapsular tumor extension and regional lymphadenopathy is unreliable, but current radiographic techniques delineate the level of thrombus extension for surgical approach with high accuracy.

Magnetic resonance imaging of renal carcinoma with extension into the vena cava: staging accuracy and recent advances

In 16 patients with surgical confirmation of inferior vena cava thrombi from renal carcinoma, magnetic resonance imaging (MRI) and computed tomography (CT) were compared to assess the ability of non-invasive, cross-sectional imaging techniques to detect tumour thrombus, the level of its extension, and vessel wall invasion. MRI accurately detected tumour thrombus in the inferior vena cava in all 16 cases (CT in 14) and demonstrated the cephalad extent of tumour thrombi in 15 of 16 (CT in 11). The level of extension was more easily seen on MRI, as was the presence of extension into the hepatic veins--a finding not detected by CT. Tumour invasion of the wall of the inferior vena cava was correctly demonstrated in 7 cases on MRI and in 1 case on CT. In 8 of 16 patients, gradient recall acquisition in steady state (GRASS imaging) was performed in addition to conventional spin echo sequences and it correctly identified the composition of thrombus in all: tumour in 6 patients, blood clot in 1 and both tumour and blood clot in the remaining patient. MRI and CT are excellent for detection of tumour but MRI is superior in the evaluation of vascular extension. In addition, the use of GRASS imaging allows differentiation of tumour from blood thrombus.

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.

Comparison of excretory urography, angiography, ultrasound and computed tomography for T category staging of renal cell carcinoma

The diagnostic significance of excretory urography, renal angiography, ultrasound and computed tomography for predicting the stage of tumours was evaluated by comparing their results with peroperative and histopathological findings. Thirty-nine out of 178 patients operated on for renal cell carcinoma from 1981 to 1988 were subjected to all four diagnostic procedures. The T stage was determined correctly by computed tomography in 80% of the cases, by ultrasound in 74.5%, by renal angiography in 64% and by excretory urography in 56.5%. Excretory urography did not give any significant additional information on the T category compared with the other imaging methods. Angiography is still of value in that it gives preoperative information on the collateral circulation and the number of renal arteries and their location.

Genitourinary cancer in the elderly

The subject of genitourinary cancer in the elderly becomes increasingly more important as our population of patients older than 50 years expands. Carcinoma of the kidney, bladder, and prostate all have an increasing incidence over the age of 50 and have a predilection for afflicting men more commonly than women. Etiologic factors, especially with bladder and kidney carcinomas, are well documented and in some cases preventable. Screening the urine for hematuria and careful digital rectal examinations may uncover a higher percentage of these malignancies in earlier, more curable stages. Recent advances in the treatment of all of these malignancies have improved survival and quality of life for these patients.

Vascular metastatic renal carcinoma of the maxilla. Report of two cases

Metastatic lesions of the jaws are unusual and the maxilla is rarely affected. Because of their vascular nature metastases from renal cell carcinoma may be embolized in order to palliate the patient. Two cases of renal carcinoma metastasizing to the maxilla are reported. Management of the condition is reviewed.

The detection of renal carcinoma extension into the renal vein and inferior vena cava: a prospective comparison of venacavography and magnetic resonance imaging

Accurate preoperative evaluation of the inferior vena cava and renal vein in patients with renal cell carcinoma is mandatory to plan a successful surgical approach. The presence of venous extension may alter transfusion and anesthetic requirements, as well as require the addition of a vascular surgeon to the operative team. Venacavography traditionally has been considered the most reliable method to identify tumor thrombus, although magnetic resonance imaging has been proposed as a possible noninvasive alternative. We compared prospectively the accuracy of these 2 methods in 44 consecutive patients with renal cell carcinoma who subsequently underwent nephrectomy. Of the 44 patients 11 (25%) had tumor extension into the inferior vena cava and 17 (39%) had involvement of the renal vein at operation. Venacavography and magnetic resonance imaging correctly identified 9 of the 11 patients (82%) with inferior vena caval thrombus. When the results of both tests were combined, all 11 cases of vena caval extension were identified. Venacavography was slightly more sensitive (71%) in identifying the presence of renal vein thrombus than magnetic resonance imaging (65%) but these differences were not statistically significant. Magnetic resonance imaging better localized the thrombus within the renal vein. We conclude that venacavography and magnetic resonance imaging offer equal diagnostic accuracy in the identification of venous extension of renal cell carcinoma. The combination of both tests results in higher diagnostic yield than either test alone. Neither test by itself is reliable in the presence of a large, bulky adenopathic lesion that compresses the inferior vena cava.

A prospective study of the value of conventional CT, dynamic CT, ultrasonography and arteriography for staging renal carcinoma

The value of dynamic CT scanning for staging renal carcinoma was studied prospectively in 28 patients and the results compared with those of ultrasonography, arteriography and conventional CT. Arteriography correctly staged 48% of tumours; ultrasonography and conventional CT correctly staged 50% and dynamic CT correctly staged 72%. Dynamic CT staged renal carcinoma more accurately than ultrasonography, conventional CT or arteriography and it is suggested that arteriography should be restricted to specific indications such as the mapping of arterial anatomy and therapeutic renal artery embolisation.