Stromal p16 expression differentiates endometrial polyp from endometrial hyperplasia

Area of Science:

• Gynecologic Pathology
• Oncology
• Cellular Biology

Background:

• Endometrial polyps are common benign lesions with unclear pathogenesis.
• Distinguishing endometrial polyps from endometrial hyperplasia on biopsy is challenging.
• No reliable immunohistochemical markers currently exist for this differential diagnosis.

Purpose of the Study:

• To investigate the utility of p16 expression as an immunohistochemical marker.
• To differentiate between endometrial polyps and endometrial hyperplasia.
• To assess p16 expression in both stromal and glandular compartments.

Main Methods:

• Examined p16 expression in 35 endometrial polyps and 33 endometrial hyperplasia cases.
• Included simple, complex, and complex atypical hyperplasia subtypes.
• Analyzed stromal and glandular p16 immunoreactivity.

Main Results:

• Stromal p16 expression was significantly higher in endometrial polyps (89%) compared to hyperplasia (3%).
• Glandular p16 expression showed no significant difference between polyps and hyperplasia.
• Stromal p16 positivity in polyps was predominantly around glands.

Conclusions:

• Stromal p16 expression is a potential diagnostic marker for endometrial polyps.
• This marker may improve diagnosis, especially in fragmented biopsy samples.
• Stromal p16 expression could be linked to p16-induced cellular senescence.