The role of adenomyosis in uterine endometrial cancer (Em Ca) invasion to myometrium

5179 Background: It is unclear what adenomyosis play roles in Em Ca invasion. Methods: Eighty five patients with Em Ca (stage 0=31, 1a=15, 1b=21, 1c=8, 2b=2, 3a=3, 3c=4, 4a=1, Age 22–82 years old, mean 54.1) received operative therapy with hysterectomy between January 2001 and November 2004. Evaluation of stromal reaction using immunohistochemical method with alpha-smooth muscle actin and h-caldesmon antibody. In case of alpha-smooth muscle actin had immunoreactivity and h-caldesmon had not immunoreactivity, there was stromal reaction with myofibroblast. Immunoreactivity scored from zero to four degrees. Results: Forty seven patients had adenomyosis in 85 Em Ca patients. In nine cases, Em Ca invaded near to adenomyosis lesion. In thirty nine cases with myometrial invasion (stage 1b-), all cases had stromal reaction with myofibloblast in myometrial invasion area (scored 1–10 cases, 2–15 cases, 3–10 cases, 4–4 cases). In contrast, nine cases with Em Ca invasion near to adenomyosis, stromal reaction with myofibloblast score were more high (scored 1–0 cases, 1–0 case, 2–3 cases, 3–3 cases, 4–3 cases). Conclusions: When Em Ca invaded around the adenomyosis in myometrium, stromal rection with myofibloblasts appeared stronger than in myometrium without adenomyosis. This may be the adenomyosis reaction of protection from Em Ca invasion. No significant financial relationships to disclose.