목적: It has been reported that levels of circulating chromatin (CC) are associated with tumour burden. These levels have prognostic significance and help in assessing treatment response. Studies have shown dramatic rise in their levels following chemotherapy and/or radiotherapy. However, studies highlighting the effects of surgical removal of tumour on levels of CC are scarce. We studied the impact of surgical removal of tumour on the levels of CC in stage IV head & neck squamous cell carcinoma (HNSCC). 방법:5 ml blood was collected from 25 treatment nave patients of stage IV HNSCC. Blood was also collected from 5 patients undergoing surgery for benign conditions of thyroid & parotid glands who acted as controls in the study. Following time points were used for blood collection1) Pre-operative (after induction of anesthesia) 2) Immediate Post-operative (during reversal of anesthesia) 3) Post-operative day 1 4) Post-operative day 4 and 5) Post-operative day 7. The serum CC levels were measured using Cell Death Detection ELISA plus kit (Roche) based on quantitative sandwich-enzyme-immunoassay principle. 결과:In patients of HNSCC the pre-operative CC levels were high and decreased dramatically in the immediate post-operative period (p<0.039). Controls showed low pre-operative CC levels and the change after surgery was not significant (p< 0.109). Patients with primary tumour in tongue had reduced pre-operative chromatin level as compared to other sub-sites of oral cavity (p<0.020). Pre-operative CC did not show any statistically significant relation with grade of tumour diffrentaition (GTD) (p<0.565), extra-capsular spread (ECS) (p<0.853), lympho-vascular emboli (LVE) (p<0.261) and peri-neural invasion (PNI) (p<0.70). 결론:This study showed elevated level of pre-operative CC in HNSCC patients was largely derived from the tumour and its removal lead to a decline in their levels after surgery. Pre-operative CC level is not statistically related to GTD, ECS, LVE and PNI.