PROBLEM: Tumor necrosis factor-alpha (TNFα) is produced by the endometrium, and it has been shown that this cytokine has cyclic variations through the menstrual cycle.
METHOD OF STUDY: In this study we assessed TNFα, estradiol and progesterone levels in the endometrium and serum of 21 patients with recent abnormal uterine bleeding (AUB). Eleven women showed histological diagnosis of endometrial hyperplasia, and ten women showed normal endometrium.
RESULTS: The TNFα value in the serum of patients with hyperplasia and in normal endometrium did not show significant differences (64.8±21.4 vs 77.6±14.8 pg). The amounts of TNFα released by hyperplastic endometrial tissue were significantly higher than in control patients (258.8±78.0 vs 140.6±79.8 pg/g; P<0.001). Immunohistochemistry of hyperplastic endometria showed a stronger staining than normal ones. Serum E2 levels in patients with hyperplastic endometrium were 49.5±31.6 ng/mL, and in controls were 107.3±66.0 ng/mL. The levels of estradiol released by hyperplastic endometria were significantly lower than in normal endometria (152.7±60.0 vs 279.9±178.7 ng/g; P<0.003).
CONCLUSIONS: Hyperplastic endometria produce higher amounts of TNFα with respect to controls. These findings may explain the frequent bleeding observed in the patients with endometrial hyperplasia, since TNFα promotes apoptosis and endometrial shedding.