Does postoperative serum interleukin-6 influence early recurrence after curative pulmonary resection of lung cancer?

We examined the influence of inflammatory cytokine levels on postoperative early recurrence in patients who underwent curative lung cancer surgery. In 107 patients who underwent curative pulmonary resections for non-small cell lung cancer (NSCLC) from November 2007 to June 2008, we measured serum interleukin-6 (IL-6) levels preoperatively, and on postoperative day (POD) 0, 1, and 2. Between July 2009 and August 2009, 1 year after the date of enrollment of the last patient, we investigated survival status of each patient and identified a group with recurrence. Among 107 patients, 29 patients developed recurrence with a mean follow-up of 18.1 months (range 14 to 21). P-stage was significantly more advanced in the recurrence group than in the non-recurrence group (p = 0.005). Serum IL-6 levels on POD 1 were significantly higher in the recurrence group than in the non-recurrence group (p = 0.007). In Cox's proportional hazards regression, P-stage and serum IL-6 levels on POD 1 were significant independent predicting factors for postoperative early recurrence (p = 0.006, p = 0.003). The higher the serum IL-6 levels on POD 1, the higher the risk of early postoperative recurrence, even when curative pulmonary resection can be accomplished in lung cancer patients.