Objectives: We investigated the role of cytokines tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) in cachexia development in newly diagnosed nonsmall cell lung cancer (NSCLC) patients.
Methods: : We evaluated 44 (M/F:41/3) NSCLC patients and 12 (M/F:10/2) age matched healthy smokers. NSCLC cases with a weight loss of > or =10% consisted the cachectic group (n:23, M/F:21/2) and the ones with <10% weight loss consisted the noncachectic group (n:21, M/F:19/2).
Results: Body mass index (BMI) of cachectics was significantly lower than that of noncachectics (21.0 +/- 2.9 versus 24.5 +/- 3.6, P = 0.02) and controls (21.0 +/- 2.9 versus 25.5 +/- 2.6, P = 0.01). Serum TNF-alpha level did not differ between cachectic and noncachectics (37.3 +/- 39.1 and 51.6 +/- 84.2 pg/mL, respectively). However, it was significantly higher in NSCLC patients compared with controls (44.1 +/- 64.3 and 15.1 +/- 14.3 pg/mL, P = 0.03). Serum IL-6 level was not different between 3 groups (6.4 +/- 4.1, 8.9 +/- 16.3, and 4.1 +/- 3.5 pg/mL, respectively) but it correlated significantly with TNF-alpha (r = 0.4, P = 0.006) and BMI (r = -0.3, P = 0.03). Erythrocyte sedimentation rate (ESR) correlated significantly with TNF-alpha (r = 0.4, P = 0.003) and BMI (r = -0.3, P = 0.03). Among 44 cases, survival of 12 and 17 patients was recorded in cachectics and noncachectics, with no statistical difference (12.2 +/- 3.7 and 11.2 +/- 1.0 months, respectively).
Conclusions: TNF-alpha and IL-6 levels did not differ significantly between cachectics and noncachectics. However, significant correlations between IL-6, BMI, and TNF-alpha suggested that these cytokines acted as cofactors in weight loss. Survival was neither influenced by BMI, nor the cytokine levels in the present study. The significant correlation of ESR with TNF-alpha suggested that ESR could provide valuable clue for considerable weight loss in the follow-up of NSCLC patients.