Prognosis of Japanese metastatic renal cell carcinoma patients in the cytokine era: a cooperative group report of 1463 patients.

BACKGROUND

Incidence rate of renal cell carcinoma (RCC) differs among countries. The rates of Asian countries are lower than those of countries in North America or Europe but are exceptionally high in Japanese males. Approximately 30% of patients with RCC have metastasis at initial diagnosis, and another 30% have metastasis after nephrectomy. Clinical studies of risk factors in patients with metastatic RCC (mRCC) are mainly based on data from non-Asian patients.

OBJECTIVES

We aimed to investigate the prognosis of Japanese patients and their prognostic factors.

DESIGN, SETTING, AND PARTICIPANTS: The subjects of this study were 1463 patients who were clinically diagnosed with RCC with metastasis in 40 Japanese hospitals between January 1988 and November 2002.

MEASUREMENTS

The primary end point was overall survival calculated from first diagnosis of mRCC to death or last follow-up. We also investigated the relationship between survival and clinical features.

RESULTS AND LIMITATIONS

The median overall survival time was 21.4 mo. The estimated survival rates at 1, 3, 5, and 10 yr were 64.2%, 35.2%, 22.5%, and 9.1%, respectively; they contrasted with data from the United States of 54%, 19%, 10%, and 6%, respectively for the same periods. A high percentage of patients had undergone nephrectomy (80.5%) and metastasectomy (20.8%), both of which were shown to prolong survival.

CONCLUSIONS

The median survival time in the present study was approximately twice as long as that of previous studies from North America or Europe. Early diagnosis of metastasis, nephrectomy, metastasectomy, and cytokine-based therapy seemed to improve the prognosis of RCC patients in the present study.