Hyaluronan in serum as an indicator of progressive disease in hyaluronan-producing malignant mesothelioma

BACKGROUND. Malignant pleural mesothelioma is associated in up to 70% of ca ses with an elevated content of hyaluronan (HYA) in the pleural fluid. Incr eased levels of circulating HYA have also been described. The clinical cour se of the disease can be followed by computed tomography (CT), although the re are disadvantages with serial CT scans. An easily analyzed blood test, s uch as HYA in serum, would be of value for clinical follow-up. The purpose of this study was to relate changes in serum HYA to changes in quantitative estimations of tumor volume in cases of mesothelioma. METHODS. The content of HYA in the pleural fluid was analyzed in 19 men wit h mesothelioma. CT scans were performed about every third month. The tumor volume was estimated on transilluminated CT scans with a digital planimeter . Blood samples for HYA analyses were drawn every month. The impact of the tumor burden on HYA in serum was indicated in statistical analysis by a str aight line for each patient according to the restricted maximum likelihood method. RESULTS. An elevated content of HYA, i.e., >100 mg/L, in the pleural fluid was seen in 13 of 19 patients. There was a positive correlation, although l ow, between the initial level of HYA in serum and the concentration of INA in pleural fluid. Increasing levels of circulating HYA were on average acco mpanied by an increase in tumor volume in the HYA-producing group of mesoth eliomas (P = 0.01). This was not seen in the non-HVA-producing mesothelioma s (P = 0.10). CONCLUSIONS. These results provide evidence that it should be possible to f ollow the clinical course of malignant pleural mesothelioma patients by ana lysis of circulating HYA in the subgroup of HYA-synthesizing mesotheliomas. Cancer 1999;86:2000-2005. (C) 1999 American Cancer Society.