[Consideration of the prognostic factors influencing survival after lung metastasectomy of renal cell carcinoma].

From 1989 to 2002, 9 patients with metastatic renal cell carcinoma to lung underwent lung resections for curative removal of metastatic disease in our department. Disease free interval (DFI), number and size of metastases resected (at first metastasectomy), and number of metastasized regional lymph nodes were studied after resection of pulmonary metastases. DFI were 0 to 60 months with mean value of 23 months. At first operation, single metastases accounted for 4 cases and multiple lesions more than 2 metastases accounted for 5 cases with mean value of 2.1. Maximal diameter of metastases was 10 to 50 mm with mean value of 24 mm. Regional lymph nodes metastases were demonstrated only 1 patient in 2 of No. 12 lymph nodes adjacent to metastases. At subsequent relapse, 1 patient had second-stage metastasectomy, 2 patients went on to a third phase. Four patients were lost, 2 are under treatment for newly relapsed lesions, and 3 are now free of metastases. Analysis was performed by Cox proportional hazards model of survival using these factors. Though lacking the statistical significance, only maximal diameter of metastases was prone to have influencing factor on prognosis. Survival was not related to DFI between 0 to 21 months and more than 21 months and numerous lung metastases between single metastasis and with 2 or more. In general, estimated survival rate of these patients according to Kaplan-Meier was 0% at 67 months. Considering the above results, surgical treatment for patients with metastatic renal cell carcinoma to lung should be planned carefully.

[Current status of clinical diagnosis and DNA test of von Hippel-Lindau disease in Japan].

An outline of the clinical diagnosis including the DNA testing in von Hippel-Lindau (VHL) disease is briefly explained. The current status of the diagnosis and treatment of VHL disease in Japan is also compared with those in European countries. According to the current experience in the world, DNA testing of VHL disease is regarded as one of the important references for the clinical diagnosis of this disease. We have to improve various points in the Japanese status of the clinical diagnosis, genetic counseling, treatment and follow-up in patients with VHL disease.

[A preliminary study to determine the activity of topoisomerase II in human kidney cancer cells with DNA unknotting method].

For the purpose of examining the Topoisomerase II (Topo II) activity in human kidney cancer cells, we performed experiments with using DNA unknotting method. This method check relative Topo II activity with its conversion of knotted form P4 phage DNA to unknotted form. Our preliminary results demonstrate remarkable activity of Topo II with specific conversion of knotted form P4 DNA to unknotted form in human kidney cancer cells, YCR and ACHN. Moreover, addition of etoposide to the same experiment suppressed Topo II activity in a dose dependent manner. Our results suggest that kidney cancer has a certain amount of Topo II, a target for etoposide. We believe this method is useful to measure Topo II activity in cancer cells and to estimate chemotherapeutic potential of Topo II inhibitors including etoposide in human kidney cancers.