The purpose of this study is to study the effects of EPA-enriched supplement compared with conventional supplement in malnourished head and neck cancer patients undergone surgery. Primary outcome is perioperative weight changing.

To study the effects of EPA-enriched supplement compared with conventional supplement in malnourished head and neck cancer patients undergone surgery. The patients are divided into 2 groups receiving the different formula supplements. The both supplements are isocaloric. The patients receive the supplement for 3 weeks (1 week prior to surgery and 2 weeks post surgery) Primary outcome is perioperative weight changing. Secondary outcomes are body compositions, hospital stay days, complication and co-morbidity.

Inclusion Criteria:

1. Patients diagnosed as Head an Neck cancer with pathological confirmation
2. Receiving surgery as a primary treatment
3. Malnutrition screening tool(MST) is 2 or more

Exclusion Criteria:

1. Previously irradiated patient in the Head and Neck region
2. Previously receiving chemotherapy
3. Renal insufficiency with serum creatinine > 2.5 mg/dL
4. Liver function abnormality with total serum bilirubin > 3.0 mg/dL
5. Pregnancy