Incidence and long-term prognosis of papillary renal cell carcinoma

Papillary renal cell carcinoma (pRCC) represents the largest subgroup of non-clear-cell kidney cancer. In this study, we assessed tumour characteristics and long-term prognosis of patients with pRCC in comparison with conventional clear-cell cancer (ccRCC). We evaluated 744 patients who had undergone renal surgery for RCC between 1990 and 2005. The mean follow-up was 5.6 years, the patients being followed-up until December 2007. Both groups, pRCC and ccRCC, were alike concerning age, body mass index, and the incidence of regional lymph node or distant metastasis at diagnosis. The percentage of male patients was higher in pRCC than in ccRCC (73.8 vs. 60.3%, p = 0.006). Even though patients with pRCC presented more often with smaller (p = 0.039) and low-grade tumours (p = 0.006), there was no statistically significant difference in tumour recurrence or tumour related death. Kaplan-Meier curves revealed no differences regarding tumour specific survival between pRCC and ccRCC (p = 0.94; 5-year survival 78 vs. 77%). Even though pRCC and ccRCC differ significantly in many aspects including histology and genetic alterations, their long term prognosis is comparable. As we could not confirm a favourable clinical course for pRCC in general, standardised aftercare programmes and-if necessary-systemic treatment, especially in the era of novel targeted drugs, are also needed for this common RCC subtype.