Background: Recently, a number of clinical studies have clarified the IL-6 response to trauma, burns and elective 
surgery. This study was carried out to evaluate the correlation of the serum IL-6 level with the injury severity in surgical 
cases and its value in prediction of the postoperative course and the patients outcome. 
Material and methods: This clinical study included 60 patients, 40 of them (GI) were subjected to elective surgery 
[non-complicated inguinal hernia (G I a, n = 10) chronic calcular cholecystitis (GI b, n = 20) and non -complicated colorectal cancer (GI c, n=10)] and the remaining 20 patients (GII) underwent emergency surgery (intra – abdominal sepsis of non – malignant causes (GII a, n=12) and complicated colorectal cancer (GII a, n = 8). 
All patients were subjected to clinical and conventional laboratory evaluation as well as estimation of serum IL-6 two 
hours preoperatively and on the days ½, 1, 2, 3, 4, 5, 7, and 10 postoperatively. 
Results: Group I (elective cases): The preoperative serum IL- 6 levels in GI a & b & c were 7.95 + 1.6, 8.31 + 1.5 and 20. 8 + 5.9 pg / ml respectively. Their levels started to increase 12 hours postoperatively and reached their peaks one day after operation with significant higher levels in oncological compared to non – malignant cases. Then the levels started to decrease 2 and 3 days postoperatively to reach about the preoperative levels 3 and 4 days after operation in non – malignant and oncological patient respectively. 
Group II (emergency cases): The preoperative serum IL6 levels were 225.99 + 25.30 and 260 .22 + 30.5 pg / ml in GII a & b respectively. These values started to increase postoperatively to reach their peaks one day after operation The serum levels started to decrease in the 4th and 5th days postoperatively to reach near the preoperative levels of group I. 
Conclusion: The present study proved that serum IL-6 is a sensitive non specific quantitative parameter in preoperative 
evaluation of surgical patients. 
- It also reflected the magnitude of operative trauma and could predict the outcome of these patients.