Assessment of cell cycle state may facilitate the histopathological diagnosis of malignant mesothelioma.
OBJECTIVE
The differentiation of benign pleural conditions from malignant mesothelioma may be difficult, especially with a small biopsy. We have tested the hypothesis that assessment of the cell cycle status is of value in the histopathological diagnosis of such biopsies, by comparing 33 malignant mesotheliomas with 36 cases of reactive mesothelial hyperplasia and reactive pleural fibrosis.


RESULTS
Biopsies were investigated for proliferative status by immunostaining for a novel antibody, MCM2, all of which showed nuclear expression of MCM2 at higher frequency than Ki67 (P < 0.0001). Counts in areas of maximum tumour staining showed significantly higher labelling indices (LIMax) in epithelioid and sarcomatoid mesotheliomas compared with reactive mesothelial hyperplasia and reactive pleural fibrosis (P < 0.0001 for both). Average counts (LIAve) revealed a significant increase in epithelioid mesothelioma compared with reactive mesothelial hyperplasia (P < 0.0001).


CONCLUSIONS
We consider MCM2 to be a useful adjunct in the differential diagnosis of malignant mesothelioma.
Sington
J D
JD
Department of Cellular Pathology, Stoke Mandeville Hospital, Aylesbury, UK. jamiesington@yahoo.co.uk
Morris
L S
LS
Nicholson
A G
AG
Coleman
N
N
D014408:Biomarkers, Tumor / Q000378:metabolism; D001706:Biopsy; D002452:Cell Count; D002453:Cell Cycle; D003937:Diagnosis, Differential; D004848:Epithelium / Q000473:pathology*; D005355:Fibrosis / Q000473:pathology; D006801:Humans; D006965:Hyperplasia / Q000473:pathology; D007124:Immunoenzyme Techniques; D019394:Ki-67 Antigen / Q000378:metabolism; D008654:Mesothelioma / Q000378:metabolism / Q000473:pathology*; D064111:Minichromosome Maintenance Complex Component 2; D009687:Nuclear Proteins / Q000378:metabolism; D010994:Pleura / Q000473:pathology*; D010997:Pleural Neoplasms / Q000473:pathology*
D014408:Biomarkers, Tumor; D019394:Ki-67 Antigen; D009687:Nuclear Proteins; D064111:Minichromosome Maintenance Complex Component 2