Incidence and long-term prognosis of papillary compared to clear cell renal cell carcinoma--a multicentre study.

AIM OF THE STUDY

Papillary renal cell carcinoma (pRCC) is the second most common subtype of RCC after the conventional clear cell type (cRCC). However, its characteristics and prognosis have been less intensively investigated. The aim of our study was to examine the tumour characteristics and long-term prognosis of pRCC compared to clear cell RCC (cRCC).

METHODS

In total, 4941 evaluable patients were subjected to either radical nephrectomy or nephron-sparing surgery for pRCC or cRCC at five centres in Germany (University Hospitals of Hannover, Homburg/Saar, Mainz, Ulm and Marburg) between 1990 and 2010.

RESULTS

pRCC (n=565) and cRCC (n=4376) patients were comparable with regard to mean age, clinical symptoms, tumour differentiation and regional lymph node metastases. Patients with pRCC had a significantly higher rate of organ confined tumours (pT1-2, N/M0; 74.9% versus 62.9%), less synchronic visceral metastases (9.6% versus 15.2%), and a higher 5-year CSS rate than those with cRCC (85.1% versus 76.9%). Multivariate analysis identified the papillary subtype as a significant positive prognostic factor in localised (HR, 0.45) but as a negative prognostic factor in metastatic tumour stages (HR, 1.37).

CONCLUSION

pRCC can apparently be differentiated into two subgroups: an organ-confined/localised subgroup with a significantly better prognosis and an advanced/metastatic subgroup with a worse prognosis compared to cRCC.