Involuntary weight loss without specific symptoms: a clinical prediction score for malignant neoplasm.

Department of Internal Medicine, University Hospital Marqués de Valdecilla, University of Cantabria, Santander, Spain. joseluishernandez@ono.com

BACKGROUND: Involuntary weight loss (IWL) is a non-specific symptom frequently found in the setting of a malignant neoplasm. There is no established diagnostic approach for patients presenting with isolated IWL, i.e. without data suggesting a particular organ involvement or system disorder. AIM: To assess the clinical probability of cancer in patients with isolated IWL by means of a score based on simple clinical and laboratory parameters. DESIGN: Retrospective analysis, followed by prospective model validation. METHODS: We analysed data from 328 patients who were treated at our Internal Medicine Department because of isolated IWL from January 1991 to December 1997. A predictive model for cancer was developed and validated. For use in clinical practice, a prediction score was derived from the regression model. RESULTS: There were 236 in-patients (72%) and 92 out-patients (28%). Malignancies were the most frequent cause of isolated IWL (35%), followed by psychiatric disorders (24%). Age, white blood count, and serum albumin, alkaline phosphatase, and lactate dehydrogenase levels were selected as the best predictors. The regression model discriminated relatively well between patients with or without a malignant neoplasm (area under the ROC curve 0.90, 95%CI 0.88-0.92). Model sensitivity was 69%, specificity 93% and positive likelihood ratio 9.9 (using a cut-off point of 0.5). DISCUSSION: We believe this to be the first study to attempt a systematic approach to the diagnosis of isolated IWL. The approach, based on very simple clinical and laboratory data, should assist the physician in a rational approach to such patients.

PMID: 12925720 [PubMed - indexed for MEDLINE]