Serum S100B in patients with brain tumours undergoing craniotomy.

OBJECTIVE To determine pre- and postoperative serum S100B concentrations in patients with intracranial tumours that underwent craniotomy and compare the values with healthy controls. STUDY DESIGN An observational, comparative study. PLACE AND DURATION OF STUDY Neurosurgical Ward, Jinnah Postgraduate Medical Centre. Karachi, from May 2007 to April 2008. METHODOLOGY Serum S100B was measured pre- and postoperatively on days 1, 2 and 7 in 18 healthy controls and similar number of patients who underwent craniotomy for intracranial tumours. Mean pre-operative patients and control values were compared using Mann-Whitney (unpaired) or Wilcoxon (paired) tests for comparing between pre- and postoperative values. The p-value was considered significant at < 0.05. RESULTS Serum S100B concentrations were significantly higher in patients with mean value of 0.19 ± 0.12 μg/L than in healthy controls (mean 0.03 ± 0.01, p < 0.0005). Significantly raised serum S100B concentrations were observed in all postoperative samples when compared with pre-operative samples. S100B concentrations significantly increased on postoperative day 1 (mean = 0.90 ± 1.07 μg/L, p < 0.0005), decreased on day 2 (mean = 0.84 ± 0.57 μg/L, p < 0.0005). The concentrations further declined on day 7 (mean = 0.44 ± 0.43 μg/L, p = 0.005). CONCLUSION The significantly high postoperative concentrations of S100B in patients appear as a consequence of tissue damage due to surgical procedures. The absence of fall of the S100B concentration in serum from the peak value on postoperative day 1 and day 2 could provide early warning of brain tissue damage leading to neurological deterioration.