Prognostic value of preoperative microscopic hematuria in patients with non-metastatic renal cell carcinoma who underwent nephrectomy.

BACKGROUND

Microscopic hematuria is associated with various urinary system diseases and is commonly used for the diagnosis of these conditions. Its prognostic role in non-metastatic renal cell carcinoma (RCC) patients who underwent nephrectomy remains unclear.

PATIENTS AND METHODS

A retrospective analysis of non-metastatic RCC patients who underwent nephrectomy in West China Hospital of Sichuan University from 2011 to 2013 was performed. Significant microscopic hematuria (SMH), defined as a threshold with a significant impact on disease-free survival (DFS) and overall survival (OS), was determined by Kaplan-Meier curves and the Maximally Selected Log-Rank Statistic. Kaplan-Meier curves were then used to estimate patients' DFS and OS, and the log-rank test was used to examine statistical significance. Logistic regression was utilized to identify clinical-pathological factors associated with SMH, while Cox regression was employed to determine independent factors of survival.

RESULTS

A total of 773 patients were included, and 20 red blood cells per high-power field was identified as the cutoff of SMH, of which 90 patients had preoperative SMH (11.6%) and 683 patients (88.4%) did not. Larger tumor size (OR = 1.10 [per cm], 95% CI 1.01-1.19, p = 0.036) and higher Fuhrman grade (grade 3 vs. grade 1-2, OR = 1.76, 95% CI 1.09-2.83, p = 0.02; grade 4 vs. grade 1-2, OR = 2.15, 95% CI 0.73-6.31, p = 0.164) were predictors of SMH. Compared to non-SMH patients, SMH patients had poorer DFS (HR = 3.16, 95% CI 2.07-4.83, p < 0.001) and OS (HR = 2.11, 95% CI 1.34-3.32, p = 0.001).

CONCLUSION

In summary, preoperative SMH is associated with larger tumor size and higher Fuhrman grade, and it is also independently correlated with poorer DFS and OS in non-metastatic RCC patients who underwent nephrectomy.