bromochloroacetic-acid and Pleural-Diseases

We report a rare case of pleural multicystic mesothelial proliferation occurring in a 62-year-old Japanese woman. Macroscopically, the lesion consisted of multiple thin wall cysts containing clear serous fluid. Histologic studies, including hematoxin-eosin stain, as well as the immunohistochemical method, revealed that the lesion was mesothelial in origin and consistent with a reactive change.

Topics: Antigens; Connective Tissue; Cysts; Epithelium; Female; Humans; Keratins; Membrane Glycoproteins; Middle Aged; Mucin-1; Pleural Diseases; Vimentin

The usefulness of tumor marker assay in pleural effusions for differential diagnosis is still debated. From the observation of common antigens on tissue polypeptide antigen (TPA) and keratins 8, 18 and 19 and vimentin, all substances contained in normal and neoplastic mesothelium, we felt it opportune to evaluate the use of TPA assay in 105 pleural effusions (46 benign and 59 malignant). The values were much higher than those found in blood. In hydrothorax the median value was 454 U/l (range, 59-1923), in exudative effusions 846 U/l (range, 258-4485), in metastatic pleural effusions 1277 U/l (range, 58-32352) and in mesotheliomas 7705 (range, 759-16000). The maximum value found in nonmalignant effusions was 4485 U/l; this value was taken as a cutoff level, so only 29.9% of the tumors were positive to the test. Our results showed this assay to be not very important for a differential diagnosis of malignant and nonmalignant pleural effusions. Nevertheless, the different TPA patterns in mesotheliomas (66.6% positive) and metastatic pleural effusions (15.9%) suggest that further studies are warranted.

Topics: Adult; Aged; Aged, 80 and over; Antigens, Neoplasm; Diagnosis, Differential; Female; Humans; Keratins; Male; Mesothelioma; Middle Aged; Neoplasm Proteins; Peptides; Pleural Diseases; Pleural Effusion; Pleural Neoplasms; Tissue Polypeptide Antigen; Vimentin

The histological diagnosis of malignant mesothelioma of the pleura, especially the distinction from peripheral adenocarcinoma of the lung, may be difficult. The immunohistochemical reports previously published on this subject show diverging results mainly because a variety of antibodies and staining techniques have been used by the different authors. To obtain comparable and reproducible results standard techniques and commercialized antibodies should be applied in routine pathology. In order to investigate the value of immunohistochemistry for the separation of the two entities formalin fixed and paraffin embedded blocks of 47 mesotheliomas and 22 adenocarcinomas were investigated with the PAP technique and commercially available antibodies to carcino-embryonic antigen (CEA), keratin, vimentin, epithelial membrane antigen (EMA), pregnancy specific antigen (SP1), S-100 protein and monoclonal antibody lu-5 (mAB lu-5). CEA positivity was found in all 22 adenocarcinomas examined, but only 2/47 (4%) of all mesotheliomas showed a positive result. SP1 was positive in 13/22 (59%) of the adenocarcinomas, whereas only 3/47 (6%) mesotheliomas were positive for this marker. No significant difference in the rate of positive cases in the adenocarcinoma and mesothelioma group could be found with the other above mentioned antigens. The results of our study indicate that especially CEA, but also SP1 are valuable markers in the diagnosis of malignant mesothelioma.

Topics: Adenocarcinoma; Antibodies, Monoclonal; Carcinoembryonic Antigen; Diagnosis, Differential; Histocytochemistry; Humans; Immunochemistry; Keratins; Lung Neoplasms; Membrane Proteins; Mesothelioma; Mucin-1; Pleural Diseases; Pregnancy-Specific beta 1-Glycoproteins; Vimentin