Development of a new supplementary diagnostic method for endometrial cancer by flow cytometry employing anti-endometrial cancer antibody, MSN-1 and MSN-3

In cytology, it is often difficult to make a definite diagnosis of endometrial cancer. In order to devise a new supplementary method, using flow cytometry we analyzed the reactivities of endometrial cells with two monoclonal antibodies (MSN-1 and MSN-3), both of which are strongly reactive to endometrial cancer cells. Employing either or both antibodies in flow cytometry, we investigated the usefulness of this analysis for distinguishing endometrial cancer cells from normal endometrial cells. Results revealed a low positive rate for normal endometrium: 9.2% with MSN-1 and 5.0% with MSN-3. In contrast, for endometrial cancer the positive rate was high: 81.2% with MSN-1 and 43.8% with MSN-3. Combined analysis with both antibodies increased the positive rate for endometrial cancer to 93.7%. These results suggest that analysis by flow cytometry employing MSN-1 and MSN-3 may have a diagnostic value for endometrial cancer. We are also investigating the usefulness of two-color analysis using these antibodies.