Immunohistochemistry does not Reliably Distinguish Malignant from Benign Hyperplastic Mesothelial C

Another interesting study is called, -Malignant mesothelioma: cytologic diagnosis with histologic, immunohistochemical, and ultrastructural correlation.- by Leong AS, Stevens MW, Mukherjee TM - Division of Tissue Pathology, Institute of Medical and Veterinary Science, Adelaide, South Australia. - Seminars in Diagnostic Pathology 1992, 9(2):141-50. Here is an excerpt: -Abstract - The differential diagnoses of malignant mesothelioma in serous effusions include adenocarcinoma and reactive mesothelial cells. While several cytologic features are of predictive value in separating these entities, immunostaining and ultrastructural examination are important adjuncts that increase the diagnostic yield. Many of the cytomorphologic features can be correlated with immunohistochemical and ultrastructural findings. Most important among these is the ultrastructural demonstration of long, often branching microvillous processes in malignant mesothelial cells. Corresponding microvilli can be visualized by immunostaining for ep ithelial membrane antigen in both cell block preparations from effusions and biopsy specimens, allowing the identification of malignant mesothelioma. In addition, the circumferential distribution of these immunostained microvilli in cells dispersed in stromal connective tissue identifies them as malignant mesothelial cells, corresponding to the ultrastructural appearance of aberrant microvilli, which project through deficiencies in the basal lamina. These microvilli show interdigitation with stromal collagen fibers, a phenomena not observed in adenocarcinoma.-

Another study is called, -Dose-Dependent Pulmonary Toxicity After Postoperative Intensity-Modulated Radiotherapy for Malignant Pleural MesotheliomaPresented at the 48th Annual Meeting of the American Society for Therapeutic and Radiation Oncology (ASTRO), Philadelphia, PA, November 5-9, 2006. - International Journal of Radiation Oncology Biology Physics - Volume 69, Issue 2 , Pages 350-357, 1 October 2007 by David C. Rice, M.B., B.Ch. Affiliations - Department of Thoracic and Cardiovascular Surgery, The University of Texas M. D. Anderson Cancer Center, Houston, TX. Here is an excerpt: -Purpose: To determine the incidence of fatal pulmonary events after extrapleural pneumonectomy and hemithoracic intensity-modulated radiotherapy (IMRT) for malignant pleural mesothelioma. Methods and Materials: We retrospectively reviewed the records of 63 consecutive patients with malignant pleural mesothelioma who underwent extrapleural pneumonectomy and IMRT at the University of Texas M. D. Anderson Cancer Center. The endpo ints studied were pulmonary-related death (PRD) and non-cancer-related death within 6 months of IMRT.

Results: Of the 63 patients, 23 (37%) had died within 6 months of IMRT (10 of recurrent cancer, 6 of pulmonary causes [pneumonia in 4 and pneumonitis in 2], and 7 of other noncancer causes [pulmonary embolus in 2, sepsis after bronchopleural fistula in 1, and cause unknown but without pulmonary symptoms or recurrent disease in 4]). On univariate analysis, the factors that predicted for PRD were a lower preoperative ejection fraction (p = 0.021), absolute volume of lung spared at 10 Gy (p = 0.025), percentage of lung volume receiving =20 Gy (V20; p = 0.002), and mean lung dose (p = 0.013). On multivariate analysis, only V20 was predictive of PRD (p = 0.017; odds ratio, 1.50; 95% confidence interval, 1.08-2.08) or non-cancer-related death (p = 0.033; odds ratio, 1.21; 95% confidence interval, 1.02-1.45).

Another study is called, -Prognostic value of the serum tumour markers Cyfra 21-1 and tissue polypeptide antigen in malignant Mesothelioma- - Volume 25, Issue 1, Pages 25-32 (July 1999) - International Journal for Lung Cancer. Here is an excerpt: -Abstract - In malignant mesothelioma, survival is claimed to be related to age, duration of symptoms, performance status, histological subtype, stage and platelet count. However the exact prognostic value of these factors is still a matter of debate. We studied the two cytokeratin markers, Cyfra 21-1 and Tissue polypeptide antigen (TPA) for their significance in predicting survival retrospectively in 52 patients. Cyfra 21-1 and TPA were elevated in 26 (50%) and 30 (58%) patients, respectively, and were highly correlated (r=0.98). Univariate analysis of data from 51 patients, showed a relation with survival for performance status (P=0.010), thoracic pain (P=0.014), platelet count (P=0.027), Cyfra 21-1 (P=0.002) and TPA (P=0.003). Multivariate analysis identified ind ependent prognostic significance for performance status, platelet count and Cyfra 21-1. In addition to performance status (80) the cytokeratin markers identified patients with good prognosis in a log rank test. Values of Cyfra 21-1 and TPA are significantly correlated.

We all owe a debt of gratitude to these fine researchers. If you found any of these excerpts interesting, please read the studies in their entirety.

Monty Wrobleski is the author of this article. For more information please click on the following links