Treatment for low-grade and high-grade endometrial carcinoma after recurrence/relapse before the molecular targeted therapy era: A retrospective, propensity score-matched cohort study

Aim: To compare the prognosis of low-grade endometrial carcinoma (LG-EC) with that of high-grade endometrial carcinoma (HG-EC) after first recurrence/relapse before the molecular targeted therapy era.

Methods: Recurrent/relapsed endometrial cancer was diagnosed in 155 women at our hospital between January 26, 1999 and February 26, 2019. Fifty of these women received paclitaxel-carboplatin, two received doxorubicin-cisplatin, and one received docetaxel-carboplatin as postoperative chemotherapy. Two women who did not receive postoperative chemotherapy received paclitaxel-carboplatin for their first recurrence/relapse. The prognosis in these 55 women was retrospectively investigated using propensity score matching.

Results: Twenty-five women had LG-EC and 30 had HG-EC. Cox proportional hazards analysis identified response to chemotherapy for the first recurrence/relapse to be a statistically significant determinant of progression-free survival and HG-EC to be a significant determinant of overall survival. After propensity score matching, median overall survival was better in women with LG-EC than in those with HG-EC (82 months [95% CI 27-not reached] vs. 31 months [95% CI 2-47], p = 0.0127). Three women survived for at least 10 years without recurrence after completion of treatment. The interval between postoperative chemotherapy and first recurrence was more than 6 months. The recurrences resolved after multimodal treatment or aggressive chemotherapy followed by 5-12 cycles of chemotherapy other than paclitaxel-carboplatin if received postoperatively.

Conclusions: The prognosis was poorer in patients with recurrent/relapsed HG-EC than in those with recurrent/relapsed LG-EC before the molecular targeted therapy era. There were no long-term recurrence-free survivors after repeat paclitaxel-carboplatin chemotherapy.