To determine the positive rate of the CAGE questionnaire in an outpatient palliative radiotherapy clinic and to examine the association between problem drinking, pain control, and analgesic consumption, patients referred for palliative radiotherapy were screened with the CAGE questionnaire and asked to rate their symptom distress using the modified Edmonton Symptom Assessment System (ESAS). The latter instrument uses 11-point numeric scales (0 = best, 10 = worst). Their daily analgesic consumption in oral morphine equivalent was recorded. A total of 128 patients participated in the study. Only 9 patients answered one of the four CAGE questions affirmatively (positive group). All the rest answered negatively (negative group). The mean pain intensity at index site/overall pain was 4.97 +/- 3.31/3.27 +/- 2.76 for the negative group and 6.29 +/- 4.42/2.89 +/- 3.37 for the positive group. The mean total daily oral morphine equivalent for the negative and positive group were 112.35 +/- 233.58 mg and 36.82 +/- 58.85 mg, respectively. There was no significant difference found in other symptoms in the modified ESAS between these two groups. The positive rate of the CAGE in patients with advanced cancer attending an out-patient radiotherapy clinic was only 7%, and analyses were limited by the small sample size of those with a positive CAGE. Whether our observed low positive rate of CAGE represents the true prevalence of problem drinking or the CAGE questionnaire is an insensitive tool for screening problem drinking in an outpatient palliative radiotherapy clinic requires further investigation. We did not find a statistically significant worse pain intensity nor higher analgesic consumption in patients who screened positive for CAGE questionnaire.