1981 Volume 72 Issue 1 Pages 1-9
Preoperative determination of the staging of renal cell carcinoma is extremely important for decision of treating methods including operative techniques. In the present study we classified the stages of renal cell carcinoma by means of computed tomography (CT), which proved to be of great value as diagnostic aid. The results obtained are described below.
The subjects of the present study consisted of 20 patients with renal cell carcinoma who were seen at the Jikei University Hospital during the 15 months period from January 1979 to March 1980. Their age ranged from 44 to 76 years. There were 13 men and 7 women. The affected side was left in 14 cases and right in 6 cases. CT was carried out using Somatom, with scanning time 4.5sec and section thickness 0.7 or 0.8cm. In each of the 20 cases the stage was classified according to the system of Robson. Five cases were rated as stage 1, 4 cases as stage 2, 3 cases as stage 3A, 2 cases as stage 3B, one case as stage 3C, 2 cases as stage 4A, and 4 cases as stage 4B. In 18 of these cases, thus diagnosed stage was compared with the findings obtained at the time of operation, while in one case it was compared with autopsy findings.
In 5 cases the tumor was found to be confined to the renal capsule by CT, which revealed no prominence of renal contour or, if it was present at all, it had a smooth outer surface. In 4 of these 5 cases, the diagnosis as determined by CT could be confirmed by operation, while in the remaining one case the pathological findings revealed infiltration of tumor extending into the perinephric fat.
In 4 cases infiltration of tumor was shown to be extending to the perinephric fat, which was corresponding to the pathological findings in all of the 4 cases. The findings obtained in these cases included remarkably irregular contour of the tumor, blurring of perinephric fat, and thickening of Gerota's fascia.
CT showed an invasion into the renal vein or the inferior vena cava by tumor in 5 cases. These were detected by dilatation of veins and filling defects after contrast enhancement. In 4 of these 5 cases, the diagnosis as determined by CT could be confirmed by operation, while in the remaining one case the operative findings revealed no venous tumor thrombus. In addition, in other one case, in which invasion of the right vein by tumor was noted at autopsy, diagnosis could not be established by CT. Enlarged regional lymph nodes were detected by CT in 5 cases, where metastasis of tumor was confirmed pathologically also.
In 2 cases it was shown by CT that the tumor extended over Gerota's fascia to infiltrate adjacent organs, which could be confirmed by operation. CT revealed hepatic and vertebral metastasis in each one case.
A comparison of the findings obtained at operation and those at autopsy demonstrated that the stage diagnosed by CT was correct in 16 of 19 cases (84%). Therefore, it can be said that CT enables one to diagnose the staging of renal cell carcinoma easily and accurately and provide informations useful for deciding the treating method.
