It is now well known that chronic alcohol abuse is an important factor for developing head and neck squamous cell carcinoma (HNSCC). While hospitalized, these patients are at great risk for developing an unexpected alcohol-withdrawal syndrome. Compared to common markers of alcohol abuse, carbohydrate-deficient transferrin (CDT) has been found to be more sensitive and specific. It is therefore very useful for detecting alcoholism and controlling compliance of alcohol withdrawal. We analyzed the serum concentrations of CDT, liver enzymes and mean corpuscular volume in 49 male patients with HNSCC. Elevated CDT levels were found in more than 25% of patients who earlier denied a history of chronic alcohol abuse. Over one-third of these patients developed an alcohol-withdrawal syndrome. These findings demonstrated that analysis of elevated CDT serum levels was a valuable method for detecting chronic alcohol abuse and recognizing patients at risk for developing an alcohol-withdrawal syndrome post-operatively.