Masakazu Kato

OBSERVATIONS ON THE GROWTH RATE OF RENAL CELL CARCINOMA

We retrospectively reviewed the records of 18 patients to investigate the growth rate of renal cell carcinoma (RCC). Growth rates were calculated from two or more gross measurements of neoplastic foci in the kidney (6 cases) and lung (12 cases). RCCs in primary sites grew slowly and the tumor volume doubling time (DT) raged from 372 to 579 days (468 ± 84.6). Pulmonary metastases present in 12 cases grew rapidly, with a DT ranging from 20 to 154 days (89.4 ± 43.0). Tumors in both the kidney and lung were composed of cancer cells with equal proliferative activity, as determined by immunohisto chemical analysis of argyrophilic nucleolar organizer regions and proliferating cell nuclear antigen activity. Thus, our results suggest that, in addition to the proliferative activity of cancer cells, the microenvironment of the specific region is an important determinant of the growth rate of cancer cells.

Ultrasonic Diagnosis of Renal Cell Carcinoma in Hemodialysis Patients

Abdominal ultrasonic examination (US) was performed in 1556 patients on hemodialysis for 7 years and 6 months from April 1955 to September 1992. Renal cell carcinoma (RCC) proved histologically by operation was found in 36 patients (41 kidneys). Among the 36, RCC developed from the contracted kidney in 15, the individual kidney after renal transplantation in 3, and from ACDK (acquired cystic disease of the kidney) in 18. Among the 18 (ACDK), multiple tumors were found in the unilateral kidney in 8 and in bilateral kidney in 5. RCC was detected at the rate of 2.3% in patients on hemodialysis (1 out of 43). It was 29 time as high as in healthy persons (RCC was found in 22 out of 27933 at our Health Check-up Center, 0.079%). RCC was diagnosed 100% by US, 68% by CT, and 55% by angiography. US is the most excellent examination for the diagnosis of RCC in patients on hemodialysis.