Multicoloured flow cytometry to detect metastatic carcinoma in lymph node by epithelial cell adhesion molecule.

Abstract

The metastatic carcinoma in the lymph node may be missed in routine fine needle aspiration cytology (FNAC). There are limited studies on the role of epithelial cell adhesion molecule (EpCAM) in detecting metastatic carcinoma in the FNAC of lymph nodes by flow cytometry (FCM). To evaluate the role of EpCAM in flow cytometry detecting metastatic carcinoma in the fine needle aspiration cytology (FNAC) of the lymph node. In this prospective study, successive 42 cases of lymph nodes were subjected to FNAC followed by flow cytometry to detect the EpCAM positive cell population. The sample was used for cytology and FCM (CD45, CD14, and EpCAM antibodies tagged with fluorochromes). The percentage of EpCAM positive cell population in each case was calculated and compared in the metastatic carcinomas and reactive lymphoid hyperplasia (RLH) cases. There were 29 cases of metastatic carcinoma and 13 non-neoplastic cases (12 RLH and one granulomatous inflammation). The average percentages of EpCAM in metastatic carcinoma and reactive lymphoid cells were 11.37 and 1.24, respectively. The independent sample t-test showed a significant difference (0.001) in the percentage of EpCAM in the two groups. The cut of value of 3% EpCAM in FCM showed 97% sensitivity and 92% specificity to detect metastatic carcinoma in FNAC of the lymph node. The percentage of EpCAM in FCM may be helpful in detecting metastatic carcinoma in the lymph node. The FCM is a rapid and quantitative test with high sensitivity and specificity.