Advances in our ability to diagnose mesothelioma in its earlier stages are among the most important developments in the recent fight against the disease. Along with the development of more effective treatment agents, these diagnostic advances have allowed physicians to begin treatment earlier than they have previously been able to—which is a key factor in their ability to extend patient survival and to improve issues related to a patient’s quality-of-life.

These advances in these diagnostic and treatment techniques have been the result of innovative research into the disease’s underlying biological activity. As scientists and physicians have learned more about mesothelioma, they have also been able to identify prognostic indicators that have enabled them to better identify the patient classes that will respond best to aggressive treatments and those whose disease requires a more palliative therapeutic protocol. This distinction is important because aggressive treatment protocols require highly invasive surgical techniques and a significant recovery time, so patients who present with specific disease characteristics that indicate poor treatability should not be burdened with such regimens.

The quest to identify more precise prognostic indicators for mesothelioma patients has taken many forms and the variety of research that is being conducted shows the interest that international researchers are now taking in studies of pleural mesothelioma and peritoneal mesothelioma. The latest example of this research is a paper that that has been published from researchers in Turkey. In an articled entitled “Pleural Fluid Findings as Prognostic Factors for Malignant Pleural Mesothelioma,” published in the Journal of Clinical Laboratory Analysis, they report the results of a retrospective study they conducted that analyzed the characteristics of pleural fluid in patients with pleural mesothleioma for any prognostic indicators it may contain regarding overall patient survival.

Overview of the Study

The researchers report that only one previous study had analyzed pleural fluid for its prognostic benefits, but only 26 patients had been enrolled in that study. In this study, they examined 71 patient records. There were 33 males and 38 females in the study population, with a mean age of 59 years. 23 people were smokers. Even though smoking has not been shown to have any causative affect on mesothelioma genesis, it is known to be a causative factor for a number of other cardiovascular diseases.

The patients were diagnosed by cytological or histological analysis, usually with a immunohistochemical panel that tested for combinations of calretinin, epithelial membrane antigen (EMA), thrombomodulin, HBME-1, CD15, B72.3 or carcinoembryonic antigen (CEA). Pleural fluid was analyzed for a number of specific characteristics, including pleural fluid glucose levels, lactate dehydrogenase (LDH), albumin, protein-to-serum levels and pleural fluid leukocyte counts. For their reported survival figures, the authors defined survival from date of thoracentesis to time of death.

Results

When the authors analyzed the results of the entire patient cohort, they found two independent prognostic factors that were indicative of survival: the ratio of pleural fluid to serum LDH > 1.0 and total leukocyte count in the fluid. They found a mean leukocyte count of 648+-860/mm³ for the entire cohort, but a significant increase in survival for those patients with a count of >700/mm³. When patients who used diuretics were excluded from these results, they found that fluid glucose levels also achieved statistical significance as a predictor of survival.

Conclusion

This study has indicated another set of prognostic tests that physicians can use in their determination of survival and overall prognosis for patients with pleural mesothelioma. These results will need to be independently verified before their scientific and medical value can be fully validated, but this study provides valuable information about specific biological factors involved with mesothelioma. The authors also note that the low leukocyte mean suggests a “weak inflammatory reaction against the tumor” and they suggest the “stimulation of antitumor response” is a possible treatment avenue for mesothelioma patients.

Labels: diagnosis, mesothelioma, pleuralmesothelioma