Evaluating probability of cancer among older people with unexplained, unintentional weight loss.

Unexplained, unintentional weight loss (UUWL) in older people is usually multi-factorial and poses a diagnostic challenge, with cancer being the major concern. The main purpose of this study was to evaluate the effectiveness of a cancer scoring system for predicting cancer in elderly UUWL patients. From 2006 to 2007, 50 patients (mean age, 78.8+/-4.7 years, 82% male) who lost > 5% of usual body weight were enrolled. The subjects' mean body weight loss was 14.1%+/-6.6% (8.7+/-4.6 kg). After evaluation, the common diagnoses were non-malignant organic disorder (22/50, 44%), neuropsychiatric disorder (17/50, 34%), unknown (8/50, 16%), and cancer (3/50, 6%). The most rapid weight loss occurred with cancer (6.5% per month), followed by non-malignant organic disorders (5.6% per month), neuropsychiatric disorders (2.8% per month), and unknown causes (2.4% per month); the difference among the groups was significant (p = 0.023). Using a previously proposed scoring system, 42 patients (84%) had a low probability of cancer; all three cancer patients were in this category. In conclusion, the annual incidence of cancer among elderly UUWL patients was 6%, and the previously developed cancer scoring system did not effectively predict cancer occurrence. Further study is needed to develop an effective instrument to predict cancer in elderly UUWL patients.