Prognostic significance of the Heidelberg classification of renal cell carcinoma

OBJECTIVE: The specific genetic alterations characterising renal cell carcinoma (RCC) have lead to the recognition of distinctive types of tumours. In a large material of patients, the prognostic and clinical information of these different tumour types were evaluated. METHODS: Tumours from 186 patients were evaluated retrospectively according to the guidelines given by the Heidelberg Classification Conference. All patients were primarily nephrectomised and TNM staged, and the follow-up times for alive patients varied between 44 and 174 months. RESULTS: The material consisted of 145 conventional (non-papillary), 25 papillary, 12 chromophobe and 4 unclassified RCCs. There was no difference in tumour size between the different RCC types. Among patients with conventional RCC, 37% had distant metastases at the time of diagnosis, significantly more frequently than 16% in patients with papillary and 8% in chromophobe RCC (p = 0.044 and 0.048, respectively). Conventional RCC more frequently had vein invasion compared with papillary RCC (p = 0.009). Patients with chromophobe and papillary RCC survived significantly longer than patients with conventional RCC (p = 0.017 and 0.031, respectively). CONCLUSIONS: A significant difference in clinical behaviour between the different RCC types was found. Patients with conventional RCC had a higher incidence of metastases, vein invasion and had adverse survival compared with papillary and chromophobe RCCs. Thus, the RCC types recognised by specific genetic alterations seem to represent different malignant phenotypes.