Lymphopenia is an independent predictor of inferior outcome in papillary renal cell carcinoma

Abstract

PurposeLymphopenia as a likely index of poor systemic immunity is an independent predictor of inferior outcome in patients with clear cell renal cell carcinoma (RCC). We sought to evaluate the prognostic relevance of preoperative absolute lymphocyte count (ALC) in a cohort of patients with papillary RCC (PRCC). Materials and methodsA prospectively maintained, renal cancer database was analyzed. Patients with preoperative ALC, within 3 months before surgery, were eligible for the study. Those with multifocal or bilateral renal tumors were excluded. Correlations between ALC and age, gender, smoking, Charlson comorbidity index, pathologic T category, PRCC subtype, and TNM stage were evaluated. Differences in overall survival (OS) and cancer-specific survival by ALC status were assessed using the log-rank test and cumulative incident estimators, respectively. Cox proportional hazards model was used for multivariable analyses. ResultsA total of 192 patients met the inclusion criteria. As a continuous variable, preoperative ALC was associated with higher TNM stage (P = 0.001) and older age (P = 0.01). As a dichotomous variable, lymphopenia (<1,300cells/µl) was associated with higher TNM stage (P = 0.003). On multivariable analyses, controlling for covariates, after a median follow-up of 37.3 months, lymphopenia was associated with inferior OS (hazard ratio = 2.3 [95% CI: 1.2–4.3], P = 0.011) and trended to significance for cancer-specific survival (P = 0.071). Among patients with nonmetastatic disease and lymphopenia, OS at 37.5 months was shorter compared with those with normal ALC (83% vs. 93%, P = 0.0006). ConclusionsIn patients with PRCC, lymphopenia is associated with lower survival independent of TNM stage, age, and histology. ALC may provide an additional preoperative prognostic factor.