Objectives many studys may concentrate on concervative surgery just because of the younger age and good survival rate of BOT patients, but their high recurrence rate can’t be ignored. among many kinds of surgery methods, lymphadenectomy is till on controversy, is lymphadenectomy necessary for BOT patients, in other word, is it good for reducing recurrence rate? So my study just focus on analyzing the relationship between lymphadenectomy and recurrence rate of BOT patients.

Methods We performed a retrospective cohort study of women with BOT at our hospital between September2014 and September 2017. The chi-square testmethod was used to calculate the correlation of variables, and Cox regression analysis was performed to define the effects of risk factors on recurrence.

Results A total of 74 BOT patients were included in the study. The median follow-up time was 45 months., the median time to recurrence is 25 months after first surgery, the 3-year RFS is 2.7%.Cox regression analysis showed thatpathological typesand pelvic lymphadenectomy was associated with favorable RFS ((hazard ratio 7.806; 95% CI1.349–45.160; P=0.022;hazard ratio 0.077; 95% CI 0.009–0.624; P=0.016,respectively). Sub-grouped by pathological types, there is no relationship between pelvic lymphadenectomy and RFS, either mBOT or sBOT.

Conclusions Hisotological type is definitely one of factors which effects recurrence rate, sBOT is more likely to recurrence than mBOT.But for sBOT, mBOT separately in my study, lymphadenectomy is not related with lower recurrence rate, this part may need to be further studied.