Is chronic kidney disease an adverse factor in lung cancer clinical outcome? A propensity score matching study.

BACKGROUND: Comorbidity has a great impact on lung cancer survival. Renal function status may affect treatment decisions and drug toxicity. The survival outcome in lung cancer patients with coexisting chronic kidney disease (CKD) has not been fully evaluated. We hypothesized that CKD is an independent risk factor for mortality in patients with lung cancer.

METHODS: A retrospective, propensity-matched study of 434 patients diagnosed between June 2004 and May 2012 was conducted. CKD was defined as estimated glomerular filtration rate <60 mL/minute. Lung cancer and coexisting CKD patients were matched 1:1 to patients with lung cancer without CKD.

RESULTS: Age, gender, smoking status, histology, and lung cancer stage were not statistically significantly different between the CKD and non-CKD groups. Kaplan-Meier survival analysis demonstrated a median survival of 7.26 months (95% confidence interval [CI] 6.06-8.46) in the CKD group compared with 7.82 months (95% CI 6.33-9.30) in the non-CKD group (P = 0.41). Lung cancer stage-specific survival is not affected by CKD. Although lung cancer patients with CKD presented with an increased risk of death of 6%, this result was not statistically significant (hazard ratio 1.06, 95% CI 0.93-1.22; P = 0.41).

CONCLUSION: According to our limited experience, CKD is not an independent risk factor for survival in lung cancer patients. Clinicians should not be discouraged to treat lung cancer patients with CKD.