Pathological Upstaging of Clinical T1 to pT3a Renal Cell Carcinoma: A Multi-Institutional Analysis of Short-Term Outcomes

OBJECTIVE - To determine the oncological impact of pathological upstaging among patients with clinical T1 disease treated by partial (PN) or radical nephrectomy (RN).

MATERIALS AND METHODS - The Canadian Kidney Cancer Information System comprises a prospectively maintained multi-institutional database for patients with RCC.

Non-metastatic, clinical T1 (cT1) RCC cases were evaluated. Upstaging was defined as pathological T3a (pT3a) disease. Multivariate cox regression analysis identified predictors for recurrence (local recurrence/metastatic disease) while logistic regression identified predictors of pathological upstaging. Kaplan-Meir methods estimated survival.

RESULTS - Of 1448 eligible cT1 patients, upstaging was observed in 134 (9%). 1058 (73%) were treated by PN. After a median follow-up of 23 months, the 3-year recurrence free survival (RFS) was 76% in upstaged patients compared with 93% in those not upstaged (p<0.001). Controlling for age, gender, year of surgery, histology, tumor size, surgical approach and margin status, pathological upstaging was independently associated with disease recurrence (HR 2.03, 95% CI 1.12-3.68). Increasing age (OR 1.02, 95% CI 1.00-1.05), Furhman grade (OR 2.47, 95% CI 1.47-4.14) and trended towards tumor size (OR 1.16, 95% CI 1.00-1.36).

CONCLUSIONS - Pathological upstaging confers a negative prognosis and highlights the importance of accurate clinical staging. A number of factors have been identified, including some attainable by renal biopsy, that may predict upstaging and provide valuable adjunct information to inform risk stratification and management decisions among patients with clinical T1 renal masses.

Urology. 2016 Mar 31 [Epub ahead of print]

Jasmir G Nayak, Premal Patel, Olli Saarela, Zhihui Liu, Anil Kapoor, Antonio Finelli, Simon Tanguay, Ricardo Rendon, Ron Moore, Peter C Black, Louis Lacombe, Rodney H Breau, Jun Kawakami, Darrel E Drachenberg

Section of Urology, University of Manitoba, Winnipeg, Manitoba, Canada; Department of Urology, University of Washington, Seattle, Washington, USA., Section of Urology, University of Manitoba, Winnipeg, Manitoba, Canada., Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada., Cancer Care Ontario, Toronto, Ontario, Canada., Division of Urology, McMaster University, Hamilton, Ontario, Canada., Department of Urology, University of Toronto., Division of Urology, McGill University, Montreal, Quebec, Canada., Department of Urology, Dalhousie University, Halifax, Nova Scotia, Canada., Division of Urology, University of Alberta, Edmonton, Alberta, Canada., Department of Urologic Sciences, University of British Columbia, Vancouver, BC, Canada., Centre hospitalier universitaire de Québec, Quebec City, Quebec, Canada., The Ottawa Hospital Research Institute, Division of Urology, University of Ottawa, Ottawa, Ontario, Canada., Southern Alberta Institute of Urology, University of Calgary, Calgary, Alberta, Canada., Section of Urology, University of Manitoba, Winnipeg, Manitoba, Canada.