Background: The choice of appropriate therapeutic plans for primary endocervical adenocarcinomas (ECA) and endometrial adenocarcinomas (EMA) depend on the tumor's site of origin. The purpose of this study was to compare the performances of the commonly used three-marker (ER/Vim/CEA), four-marker (ER/Vim/CEA/PR) and five-marker (ER/Vim/CEA/PR/p16INK4a) panels in distinguishing between primary ECA and EMA.
Methods: A tissue microarray was constructed using paraffin-embedded, formalin-fixed tissues from 35 hysterectomy specimens, including 14 ECA and 21 EMA. Utilizing the avidin-biotin (ABC) technique, tissue array sections were immunostained with five commercially available antibodies (ER, Vim, CEA, PR and p16INK4a) to evaluate the performances of their respective three-, four- and five-marker panels in distinguishing between primary ECA and EMA.
Results: ER, PR and Vim were more likely to be expressed in EMA, while CEA and p16INK4a were frequently expressed in ECA. The three-marker (ER/Vim/CEA) panel exhibits the most favorable performance in the distinction between these two gynecologic malignancies (ECA vs. EMA).
Conclusion: According to our data, when histomorphological and clinical doubt exists as to the primary site of origin, we recommend that the conventional three-marker (ER/Vim/CEA) panel is sufficient, appropriate and useful in distinguishing between primary ECA and EMA, instead of the four-marker (ER/Vim/CEA/PR) and five-marker (ER/Vim/CEA/PR/p16INK4a) panels. Ancillary PR and p16INK4a add no supplementary value to the performance of the conventional three-marker (ER/Vim/CEA) panel.