RENAL-CELL CARCINOMA IN NEW-ZEALAND - A NATIONAL SURVIVAL STUDY

Objective. To determine clinical and pathologic prognostic factors for renal cell carcinoma (RCC) using cases reported to a population-based cancer registry. Methods. All cases of RCC reported to the New Zealand Cancer Registry between 1976 and 1986 were retrieved and data analyzed to determine parameters of prognostic importance. Results. In eleven years, 1,308 cases of RCC (66.7% males and 33.3% females) were reported to the New Zealand Cancer Registry. The age-standardized incidence rate was 3.78 per 105 person-years and showed no significant trend over the period of the study. There was a significant difference in the age at presentation between the largest racial groups (Maori 52.2 years; non-Maori 63.2 years), which is accounted for by increased predisposing risk factors among Maori. The five-year actuarial survival rate was 42.4 percent with 63 percent of patients reported dead in follow-up to December 1990. In the series, patient gender (female > male), tumor laterality (right > left), stage (intrarenal > localized > disseminated), grade (1 > 2 > 3 > 4), and treatment modality (surgery > nonsurgery) were found to be significant prognostic factors, although only tumor stage and treatment modality were of independent significance. Tumor laterality was of prognostic significance for Stage II (localized) surgically treated tumors only. Conclusions. The results of the study emphasize the paramount importance of tumor stage as a prognostic parameter for RCC. The prognostic significance of laterality for localized, surgically treated tumors suggests that radical nephrectomy is less likely to result in tumor clearance for left-sided RCC than for tumors on the right side.