Value of Claudin-4 Immunostaining in distinguishing Adenocarcinoma from Reactive mesothelium in Effusion fluid Cytology

Dr. Amit Pal; Dr. Jayati Chakraborty; Dr.Biswajit Biswas

Volume : VI, Issue : VIII, August - 2017

Value of Claudin-4 Immunostaining in distinguishing Adenocarcinoma from Reactive mesothelium in Effusion fluid Cytology

Dr. Amit Pal, Dr. Jayati Chakraborty, Dr. Biswajit Biswas

Abstract :

BACKGROUND- Morphological distinction between metastatic carcinoma cells & reactive mesothelial cells is difficult in many occasions in effusion cytology. Immunohistochemistry plays important role in distinguishing the two. Immunohistochemistry for claudin-4, has shown to distinguish adenocarcinoma from reactive mesothelium effectively.

AIMS- Our aim was to validate and assess the Immunoreactivity profile of claudin-4 in a series of malignant and benign effusions.

MATERIALS AND METHODS:- Total 84 samples were taken, 38 containing reactive mesothelial cells & 46 containing adenocarcinoma cells. Claudin-4 immunohistochemistry was performed on cell-block paraffin sections and scored for staining intensity, staining pattern and percentage of positive tumor cells.

RESULTS- In 46 cases of metastatic adenocarcinomas, 44 cases were positive for

Claudin-4 & among the 38 non-malignant effusion cases where the fluid contained

reactive mesothelial cells, none of them were positive for Claudin-4. Sensitivity & specificity of claudin-4 in diagnosing adenocarcinoma were 95.6% & 100% respectively.Positive Predictive Value & Negative Predictive Value of claudin-4 in diagnosing adenocarcinoma were 100% & 95% respectively.

CONCLUSIONS: Claudin-4 immunohistochemistry effectively distinguishes adenocarcinoma from reactive mesothelium with high sensitivity and specificity.