The Prognostic Impact of Tumor Size on Cancer-Specific and Overall Survival Among Patients With Pathologic T3a Renal Cell Carcinoma

BACKGROUND: We aimed to determine the prognostic role of tumor size in patients with stage pT3a renal cell carcinoma (RCC). PATIENTS AND METHODS: We analyzed our database of patients who underwent radical nephrectomy for RCC between July 2000 and December 2013. Clinical and pathologic data were obtained for each patient. Patients with stage pT3a disease were divided into 2 subgroups according to the most informative threshold for pathologic tumor dimension that was able to predict survival outcomes (group 1, ≤ 8 cm; group 2, > 8 cm). RESULTS: Globally, 185 consecutive patients were evaluated. The median (interquartile range [IQR]) follow-up was 32 months (18-62 months). The median (IQR) pathologic tumor size was 7.5 cm (5.7-10 cm). Seventy (34.3%) patients died of RCC during the follow-up period. Patients in group 2 experienced worse cancer-specific survival (CSS) rates compared with those in group 1, (5- and 10- year CSS, 52% and 40% vs. 67% and 63%, respectively; P = .001). Overall survival (OS) rates were significantly lower for patients included in group 2 compared with patients in group 1 (5- and 10- year OS rates, 46% and 38% vs. 60% and 57%, respectively; P = .01). Subgroup stratification (hazard ratio [HR], 3.65; P < .001), presence of positive surgical margins (HR, 3.86; P = .22), high Fuhrman grade (HR, 4.33; P < .001), and the presence of sarcomatoid cells (HR, 2.61; P = .02) were found to be independent predictors of CSS. CONCLUSION: Worse oncologic outcomes are observed in patients with stage pT3a RCC tumors > 8 cm. The current TNM classification still does not precisely correlate with CSS. Tumor size should be taken into account in a future revision of the TNM staging system.