Background: Over-expression of fatty acid synthase (FAS), the enzyme involved in the anabolic conversion of dietary carbohydrates to fatty acid, has been reported in many human malignancies. This study investigated whether clinicopathological findings [histological grade, myometrial invasion, vessel permeation, lymphatic permeation, nodal metastasis, and Federation of International Gynecologic Obstetrics (FIGO) stage] and body fat distribution differ with the level of FAS expression in endometrial cancer.
Methods: Subjects were 73 postmenopausal women (mean age, 62.2 +/- 7.4 years; range, 49-75 years) with endometrioid adenocarcinoma. Baseline characteristics included age, height, body weight (BW), body mass index (BMI), and years since menopause (YSM). Percentage of body fat and the trunk-leg fat mass ratio were measured by dual-energy X-ray absorptiometry. FAS expression was determined using immunohistochemical methods in formalin-fixed and paraffin-embedded cancer specimens. FAS expression was defined as none, low, and high.
Results: Sixty-six (90.4%) cases showed positive FAS status. Sixty-nine percent of cases showed myometrial invasion > or =1/2, 50% of cases showed myometrial invasion <1/2, and 23% of cases without myometrial invasion demonstrated a positive FAS status. Lymphatic permeation, vessel permeation, nodal metastasis, and advancing FigO stage were associated with FAS status. The trunk-leg fat ratio and BMI in high and low FAS status groups were significantly greater than that in those not expressing FAS (p < 0.05). However, age, height, weight, YSM, and percentage of body fat did not differ with FAS status.
Conclusion: FAS expression in endometrial cancer is associated with cancer progression and upper body fat distribution.