Risk factors for lower limb lymphedema in gynecologic cancer patients after initial treatment

BACKGROUND: Most studies on lower limb lymphedema have been conducted in gynecologic cancer patients who underwent surgery for gynecologic malignancy. This study aimed to evaluate the risk factors for lower limb lymphedema development in gynecologic cancer patients who underwent initial treatment. METHODS: A retrospective cohort design was used to follow 903 gynecologic cancer patients who underwent treatment at Kurume University Hospital between January 1, 2013 and December 31, 2015. Data analyses were performed in 356 patients, and the patients were followed up until December 31, 2017. The model comprised two components to facilitate statistical model construction. Specifically, a discrete survival time model was constructed, and a complementary log–log link model was fitted to estimate the hazard ratio. Associations between risk factors were estimated using generalized structural models. RESULTS: The median follow-up period was 1083 (range 3–1819) days, and 54 patients (15.2%) developed lower limb lymphedema, with a median onset period of 240 (range 3–1415) days. Furthermore, 38.9% of these 54 patients developed lower limb lymphedema within 6 months and 85.2% within 2 years. International Federation of Gynecology and Obstetrics stage, radiotherapy, and number of lymph node dissections (≥ 28) were significant risk factors. CONCLUSION: Simultaneous examination of the relationship between lower limb lymphedema and risk factors, and analysis among the risk factors using generalized structural models, enabled us to construct a clinical model of lower limb lymphedema for use in clinical settings to alleviate this condition and improve quality of life.