Risk factors for lower extremity lymphedema after cervical cancer treatment: a systematic review and meta-analysis

Background: The main risk factors for the development of lower extremity lymphedema after cervical cancer treatment are controversial. Our aim was to evaluate the main risk factors of lower extremity lymphedema after cervical cancer treatment. Methods: We searched the English database PubMed, Embase, Medline, Central and the Chinese database CNKI to obtain relevant studies. Inclusion criteria: (I) the subjects were cervical cancer patients receiving treatment; (II) cohort studies or case-control studies; (III) exposure factors were not limited; (IV) the outcome was lower extremity lymphedema after treatment; (V) the odds ratio (OR) value and 95% confidence interval of exposure factors can be obtained. The chi-square test was used to test for heterogeneity. The Egger test was used to test for publication bias. OR (95% CI) was calculated using inverse variance. Results: A total of 12 retrospective studies with a total of 3,401 patients were included in this literature review. The incidence of lower extremity lymphedema after cervical cancer treatment was between 12.6% and 43.1%. Meta-analysis results demonstrated that the main risk factors were: body mass index (BMI) (OR =1.37, 95% CI: 1.10-1.71, P=0.005), age (OR =1.68, 95% CI: 1.07-2.64, P=0.02), International Federation of Gynecology and Obstetrics (FIGO) stage (OR =1.50, 95% CI: 1.24-1.82, P<0.001), radiotherapy (OR =2.87, 95% CI: 1.71-4.82, P<0.001), lymph node (LN) dissection (OR =3.24, 95% CI: 1.44-7.31, P=0.005), and the number of LNs dissected (OR =2.34, 95% CI: 1.80-3.05, P<0.001). Egger's test showed that there was no publication bias among the literatures (P>0.05). Conclusions: BMI, age, FIGO stage, radiotherapy, LN dissection and the number of LNs removed are the main risk factors for lower extremity lymphedema after cervical cancer treatment. When treating patients with cervical cancer, effective interventions should be sought to reduce the risk of lower extremity edema.