Diagnostic utility of whole body CT scanning in patients with unexplained weight loss

Abstract

BackgroundUnexplained weight loss is a non-specific complaint with myriad potential etiologies. Increasingly, whole body CT studies are being performed in patients with unexplained weight loss to exclude organic etiologies such as malignancy. Our study aims to assess the diagnostic accuracy and yield of whole body CT in these patients.Methods and materialsPatients who had a whole body CT scan for investigation of unexplained weight loss as their primary complaint from 2009–2012 were retrospectively reviewed. CT scans were classified into 4 categories: (1) Definite/highly suspicious for underlying organic cause (2) Indeterminate for underlying organic cause (3) No findings accounting for weight loss and only incidental findings and (4) Normal study. Scan findings were correlated with the final diagnosis after all investigations. Univariate logistic regression was performed to determine associations between patient’s baseline variables and positive CT scan findings.ResultsOf 301 eligible patients during the study period, 101 patients were excluded due to known history of malignancy, inadequate follow-up or inadequate scan technique. 200 patients were included in the final analyses. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of CT for organic pathology were 72.0%, 90.7%, 87.0%, 78.9% and 82.0% respectively. Additional symptoms, abnormal physical examinations, anemia, and raised tumor markers were significantly correlated with positive CT findings. Overall, the diagnostic yield of whole body CT scan for patients with unexplained weight loss was 33.5%.ConclusionsWhole body CT imaging may be a useful investigation for the noninvasive workup of patients with unexplained weight loss, with diagnostic yield of 33.5% and good sensitivity, specificity, positive and negative predictive values for organic etiologies.

Is CT thorax, abdomen and pelvis a useful test in patients with weight loss?

“…Our findings differ somewhat from a previously published study by Goh et al 3 . on the role of whole‐body CT in the work up of unexplained weight loss.…”

“…Our findings differ somewhat from a previously published study by Goh et al 3 on the role of whole-body CT in the work up of unexplained weight loss. Goh's study of 301 patients in a different population group found that CT had a diagnostic yield of 33.5% in patients with unintentional weight loss, higher than in our study.…”

“…Goh et al 3 . also found a positive association between additional symptoms, anaemia and elevated tumour markers, and positive CT findings.…”

“…This is likely a reflection of the different population groups in the two studies. Goh et al 3 also found a positive association between additional symptoms, anaemia and elevated tumour markers, and positive CT findings. Our study did not identify such an association.…”

Deep Cancers in Uncontrolled Diabetes and Weight Loss

“…Although weight loss was not the primary reason to perform a scanner in Damiano's study, it was the only significant difference between the tumorbearers (-6.9±5.8 kg) and the others (-3.8±4.5 kg). Higher rates of cancers (28% to 36%) were reported in radiologic series using a CTscanner in patients with unexplained weight loss, not selected for uncontrolled diabetes [9,19], probably due to additional localizing symptoms, anemia and elevated tumor markers in these series. The detection of a deep cancer on 6.1% of CT-Scanners shows that this exam should be considered in subjects with uncontrolled diabetes and an unexpected weight loss.…”