Predictive factors of trophoblastic invasion into the ampullary region of the tubal wall in ectopic pregnancy

BACKGROUND: Predictive factors of damage to the Fallopian tube may guide the treatment for patients with tubal pregnancy. The aim of this study was to assess the predictive value of the following parameters: gestational age, serum beta-hCG concentrations and ultrasound findings. METHODS: A total of 105 patients with ampullary pregnancy undergoing salpingectomy were analysed. Trophoblastic invasion was histologically classified as stage I when limited to the tubal mucosa, stage II when extending to the muscle layer and stage III in the case of complete tubal wall infiltration. We correlated the depth of trophoblastic infiltration into the tubal wall with gestational age, beta-hCG concentration on the day of surgery and the type and size of the ectopic mass upon ultrasound. RESULTS: No association was observed between the depth of trophoblastic invasion and gestational age (P = 0.53) or tubal mass diameter (P = 0.43). Trophoblastic invasion was, however, associated with beta-hCG concentration (P < 0.001) and with the type of ultrasonographic image (P = 0.001). beta-hCG levels of 2400 mIU/ml showed 82.8 % sensitivity and 85.5 % specificity for stage 1, and levels of 5990 mIU/ml showed 82.6 % sensitivity and 74.6 % specificity for stage III. CONCLUSIONS: Depth of trophoblastic penetration into the tubal wall of the ampullary region of Fallopian tube is correlated with beta-hCG concentration and the type of ultrasonographic image; serum beta-hCG is the best predictor of the depth of penetration.