Abstract

Lower Extremity Lymphedema in Gynecologic Cancer Patients: Propensity Score Matching Analysis of External Beam Radiation versus Brachytherapy

WonIck Chang 1,Hyun-Cheol Kang 1,*,Hong-GyunWu 1,2,3,HakJ ae Kim 1,Seung Hyuck Jeon 1, Maria Lee 4 , Hee Seung Kim 4, Hyun Hoon Chung 4, Jae Weon Kim 4, Noh Hyun Park 4, Yong Sang Song 4 and Kwan-Sik Seo. Cancers 2019, 11, 1471.

The goal of this study is to compare the risk of lower extremity lymphedema (LEL) between pelvic external beam radiation therapy (EBRT) and vaginal brachytherapy, and to identify risk factors for LEL in gynecologic cancer patients treated with adjuvant radiation therapy (RT) after radical surgery.

A total of 263 stage I–III gynecologic cancer patients who underwent adjuvant RT were retrospectively reviewed. One-to-one case-matched analysis was conducted with propensity scores generated from patient, tumor, and treatment characteristics. Using the risk factors found in this study, high- and low-risk groups were identified. With a median follow-up of 36.0 months, 35 of 263 (13.3%) patients developed LEL. In multivariate analysis, laparoscopic surgery (HR 2.548; p = 0.024), harvesting more than 30 pelvic lymph nodes (HR 2.246; p = 0.028), and para-aortic lymph node dissection (PALND, HR 2.305; p = 0.014) were identified as independent risk factors for LEL. After propensity score matching, the LEL incidence of the brachytherapy group was significantly lower than the EBRT group (p = 0.025).

In conclusion, high-risk patients with risk factors such as laparoscopic surgery, harvesting more than 30 pelvic lymph nodes, PALND, and adjuvant pelvic EBRT require closer observation for LEL.

Main findings

• The type of surgical approach was associated with LEL development.
  There is higher incidence of LEL in endometrial cancer patients after laparoscopic hysterectomy plus pelvic lymph node dissection (PLND) compared to laparotomy (10.6% vs. 1.6%).
• This may be due to longer surgery time, greater number of lymph nodes removed and increased insult to the lymphatics accompanying laparoscopy.
• hHrvesting more than 30 pelvic lymph nodes, para-aortic lymph node dissection, laparoscopic surgery, and pelvic EBRT were associated with a higher incidence of LEL in gynecologic cancer patients treated with adjuvant RT. Combining these risk factors, we developed a prediction model to estimate the probability of LEL. The high-risk group identified with this model may require closer observation for LEL in order to facilitate early diagnosis and management.