Clinical evaluation of four tumor markers in malignant and benign pleural effusions.

Total sialic acid (TSA), lipid-bound sialic acid (LSA), ferritin and carcinoembryonic antigen (CEA) were evaluated in 55 patients with malignant pleural effusions and in 32 patients with benign (exudative) pleural effusions. No significant differences were found in the pleural fluid TSA, LSA and ferritin levels between malignant and benign conditions. CEA levels in malignant effusions were significantly higher than those in benign effusions (43.13 +/- 72.8 ng/ml versus 2.6 +/- 5.56 ng/ml, p less than 0.01). At a cut-off level of 5 ng/ml, 60% of the patients with cancer showed elevated pleural fluid CEA levels. The specificity and diagnostic accuracy of CEA in distinguishing malignant from benign pleural exudates were both very high (91% and 71% respectively). Therefore, of the four markers investigated, only CEA could be a valuable tool in the detection of pleural malignancy.

Five tumor markers in lung cancer: significance of total and "lipid"-bound sialic acid.

Total sialic acid (TSA) and "lipid-bound" sialic acid (LSA) were evaluated in comparison to carcinoembryonic antigen (CEA) and ferritin and neuron specific enolase (NSE) in 152 untreated patients with primary lung cancer, 107 benign pulmonary disease patients and 207 notmal controls. The mean concentrations of TSA, LSA and CEA in lung cancer patients, were significantly higher than in benign and normal controls (p less than 0.001), while the mean ferritin and NSE levels were significantly higher than in normal controls only (p less than 0.001). At the designated cut-off serum levels, sensitivities of the five markers for lung cancer were in decreasing order: TSA 86.5% (greater than 80 mg/dL), LSA 77% (greater than 20 mg/dL), CEA 46.4% (greater than 5 ng/mL), ferritin 36% (greater than 300 ng/mL) and NSE 34.5% (greater than 12.5 ng/mL). Using the benign pulmonary values as negative controls the specificity of each marker was as follows: CEA 88%, ferritin 72%, NSE 58%, TSA 44% and LSA 44%. In small cell lung cancer (SCLC) patients, NSE mean concentrations and sensitivity were significantly higher than in non-small lung cancer (NSCLC) patients (9.63 +/- 4.4 versus 23.54 +/- 16.9, p less than 0.001 and 74% versus 21.4% respectively). While in NSCLC patients only CEA levels correlated well with the stage of the disease, in SCLC patients concentrations of TSA, LSA and ferritin were significantly higher in extensive than in limited disease stages. These preliminary data suggest that, although TSA and LSA are highly sensitive markers in lung cancer, their specificity is low.

Total and lipid-bound sialic acid in the cerebrospinal fluid of patients with brain tumors.

Total sialic acid (TSA) and lipid-bound sialic acid (LSA) were determined in the cerebrospinal fluid (CSF) from 63 patients with various neurological diseases. Of these, 27 had brain tumors: 20 had glioma, and 7 pituitary adenoma. TSA levels were significantly increased in the CSF of 18 of the 20 glioma patients (p less than 0.001), while in the adenoma patients were indistinguishable from the controls; with a 90 and 0% test sensitivity respectively. Conversely, the LSA concentrations were significantly elevated, both, in the glioma and pituitary adenoma patients (p less than 0.001), with a 68 and 100% test sensitivity respectively. These preliminary data suggest that measurement of TSA and LSA in the CSF should prove useful for the diagnosis of brain tumors and, perhaps, in the follow-up of patients undergoing treatment for brain tumors.