Tumour Markers in the Differential Diagnosis of Patients With Isolated Involuntary Weight Loss.

BACKGROUND/AIM: Paraneoplastic syndrome symptoms include isolated involuntary weight loss (IIWL). The differential diagnosis of cancer from other diseases may require a significant number of tests. Tumour markers (TMs) can be used for the diagnosis and stratification of patients according to cancer risk. PATIENTS AND METHODS: This study included 606 patients (48% females) seen at the rapid diagnostic unit for IIWL. We determined the levels of TMs carcinoembryonic antigen, carbohydrate antigen 19-9, soluble fragments of cytokeratin 19, carbohydrate antigen 15-3, carbohydrate antigen 125, neuron specific enolase, alpha-fetoprotein, prostatic specific antigen using the multiparametric analyser COBAS 601. Two cut-off points were established, the upper reference limit described by the manufacturer and a high cut-off point suggested by Molina et al., to stratify patients according to cancer risk. RESULTS: Patients were classified according to TM levels as follows: I) all TMs below the upper reference limit; II) highest number of TMs between the two cut-offs; III) at least one TM above the higher cut-off. The odds ratio for malignancy was 4.3 for group II and 248 for group III. These results indicate that when at least one TM is above the higher cut-off, neoplasia is highly probable. CONCLUSION: TM determination allowed to establish cancer risk in patients with IIWL.

Etiologies and 12-month mortality in patients with isolated involuntary weight loss at a rapid diagnostic unit.

BACKGROUND: Numerous studies on involuntary weight loss (IWL) have been published since the 1980s, although most of them have included small samples of patients with specific symptoms. The aim of the present study was to determine the causes, demographic and clinical characteristics and mortality at 12 months in patients attended at a rapid diagnostic unit (RDU) for isolated IWL. METHODS: A single-center retrospective observational study including all patients presenting to the RDU for isolated IWL between 2005 and 2013. The following data were recorded: demographic and clinical variables, results of complementary tests (blood tests, x-rays, computed tomography scan and digestive endoscopy), main diagnosis and vital status at 12 months. RESULTS: Seven hundred and ninety-one patients met the criteria for IWL. Mean age was 67.9 years (SD 4.7), 50.4% were male and mean weight loss was 8.3 kg (SD 4.7). The cause for IWL was malignant disease in 23.6% of patients, non-malignant organic disease in 44.5%, psychiatric disorder in 29.0% and unknown in 3.2%. Overall mortality at 12 months was 18.6% (95%CI: 16.1-21.6). The mortality rate was highest in the group with malignancy (61.1%; 95%CI: 54.2-68.2). CONCLUSIONS: Almost a quarter of all patients attended at the RDU for IWL were diagnosed with cancer. Mortality at 12 months was higher in this group than in the other three. Malignancy should therefore be ruled out during the first visit for patients attended for IWL.

Comparative Assessment of Two Strategies for Interpreting Tumor Markers in Ascitic Effusions.

BACKGROUND/AIM: There are two strategies for the interpretation of tumor markers (TM) in fluid effusions: i) high cut-off and ii) fluid/serum ratio (F/S) and low cut-off. The objective of this study is to compare these two strategies and to determine whether diagnostic accuracy improves by the identification of possible false positives using Adenosine deaminase (ADA), C reactive protein (CRP) and % of polymorphonuclear cells (%PN). PATIENTS AND METHODS: We studied 157 ascitic fluids, 74 of which were malignant. ADA, CRP and %PN were determined in ascitic fluid, and Carcinoembryonic antigen (CEA), Cancer antigen 72-4 (CA72-4), Cancer antigen CA19-9 and Cancer antigen 15-3 (CA15-3) in both fluid and serum. RESULTS: The strategy of high cut-off showed 59.5% sensitivity at 100% specificity. The F/S strategy showed 75.7% sensitivity at 95.2% specificity. Subclassifying cases with ADA, CRP and %PN negative showed 67.5% sensitivity at 100% specificity for high cut-off and for the F/S strategy was 81.7% sensitivity at 98.7% specificity. CONCLUSION: The strategy of F/S with negative ADA, CRP and %PN allow the best interpretation for TM in the ascitic fluid.

Diagnostic Accuracy of CYFRA21-1 in the Differential Diagnosis of Pleural Effusions.

BACKGROUND/AIM: Approximately 20% of pleural effusions are associated with cancer; about 50% require invasive procedures to perform diagnosis. Determination of the concentration of soluble cytokeratin 19-fragments (CYFRA21-1) may help identify patients with malignant effusions. However, pathologies other than cancer can increase its concentration. The identification of these possible false positives with routine tests CRP, ADA, % polymorphonuclear cells (PN) may improve diagnostic accuracy. This study aimed to determine the diagnostic accuracy of CYFRA21-1 in the detection of malignant pleural effusions and the possible false positives. MATERIALS AND METHODS: Analysis of CYFRA21-1, adenosine deaminase (ADA), C-reactive protein (CRP), and the percentage of polymorphonuclear leukocytes (PN%) in the fluid from 643 consecutive undiagnosed pleural effusions was performed. RESULTS: CYFRA21-1 showed 38.7% sensitivity and 97.3% specificity at 175 ng/ml cut-off. Effusions not suspicious of a false-positive showed 39.0% sensitivity and 98.2% specificity, while effusions suspicious of false positive showed lower sensitivity (36.4%) and specificity (95.0%). CONCLUSION: The diagnostic accuracy of CYFRA21-1 in pleural effusions can be improved by classification according to the possibility of false positives.

Evaluation of two strategies for the interpretation of tumour markers in pleural effusions.

BACKGROUND: Pleural effusions present a diagnostic challenge. Approximately 20% are associated with cancer and some 50% require invasive procedures to perform diagnosis. Determination of tumour markers may help to identify patients with malignant effusions. Two strategies are used to obtain high specificity in the differential diagnosis of malignant pleural effusions: a) high cut-off, and b) fluid/serum (F/S) ratio and low cut-off. The aim of this study is to compare these two strategies and to establish whether the identification of possible false positives using benign biomarkers - ADA, CRP and % of polymorphonuclear cells - improves diagnostic accuracy. METHODS: We studied 402 pleural effusions, 122 of them malignant. Benign biomarkers were determined in pleural fluid, and CEA, CA72-4, CA19-9 and CA15-3 in pleural fluid and serum. RESULTS: Establishing a cut-off value for each TM for a specificity of 100%, a joint sensitivity of 66.5% was obtained. With the F/S strategy and low cut-off points, sensitivity was 77% and specificity 98.2%, Subclassifying cases with negative benign biomarkers, both strategies achieved a specificity of 100%; sensitivity was 69.9% for single determination and 80.6% for F/S ratio. CONCLUSIONS: The best interpretation of TM in the differential diagnosis of malignant pleural effusions is obtained using the F/S ratio in the group with negative benign biomarkers.

Clinical utility of determining tumor markers in patients with signs and symptoms of cancer.

BACKGROUND: Diagnosing patients with signs or symptoms suggestive of cancer is difficult. Serum tumor markers (TM) may be useful, but it is known that a range of pathologies other than cancer can increase their concentrations and so TM data must be interpreted with caution. The aim of this study is to determine the diagnostic accuracy of TMs in patients with signs or symptoms of cancer. METHODS: We prospectively studied 234 patients seen at rapid diagnostic units who presented signs or symptoms suggestive of cancer. Ninety patients had wasting syndrome, 74 had pulmonary symptoms and 70 other presentations. CYFRA21-1, CEA, CA19-9, total bilirubin and creatinine were determined. The final diagnosis was obtained after 6 months' follow-up. Patients were classified according to the absence (group A) or presence (group B) of abnormal bilirubin or creatinine. RESULTS: Of the 234 patients studied, 103 (44.0%) had tumors diagnosed. Cut-off points for each TM were calculated for a specificity of 100%. For the total group, the values were CYFRA21-1, 15 µg/L, CEA, 43.8 µg/L and CA19-9, 7428 KU/L, with an overall sensitivity of 46.6%. For group A (n=142), the following cut-off points were established: CYFRA21-1, 7.8 µg/L, CEA, 13.8 µg/L and CA19-9, 101 KU/L, obtaining a sensitivity of 68.6%. For group B (n=92), the values were the same as for the whole group, and a sensitivity of 42.4% was achieved. CONCLUSIONS: We conclude that TMs can aid diagnosis in these patients with signs or symptoms suggestive of cancer. Their sensitivity can be improved by using different cut-off points in the presence and absence of renal and hepatic dysfunction.