Reduced risk of lymphedema after immediate breast reconstruction in breast cancer: a retrospective nationwide study.

This study assessed the impact of immediate breast reconstruction on lymphedema incidence in women diagnosed with breast cancer. We included 45,734 women aged ≥ 30 years treated for breast cancer (ICD-10 primary diagnostic code C50) since 2017. Propensity score-matched analysis compared patients who underwent immediate reconstruction (n = 5,256; stratified into implant and autologous groups), with those who did not (n = 5,256). Multivariate-adjusted extended Cox regression was used to assess lymphedema outcomes. Lymphedema incidences were similar between the immediate reconstruction (22.50%; 95% confidence interval [CI]: 19.60-25.30%) and no reconstruction groups (25.30%; 95% CI: 22.50-28.00%; P = 0.180). After adjusting for age, surgery type, treatments, and comorbidities, immediate reconstruction showed an inverse association with lymphedema (adjusted hazard ratio [HR], 0.76; 95% CI, 0.69-0.85). When stratified by reconstruction method, implant reconstruction exhibited a reduced risk (adjusted HR, 0.74; 95% CI, 0.67-0.82), while autologous reconstruction showed a higher risk (adjusted HR, 1.96; 95% CI, 1.39-2.78) for lymphedema. Immediate implant-based reconstruction may lower lymphedema risk, but interpretation requires caution due to potential selection bias, missing data on BMI, breast size, and applicability beyond East Asian populations. Further research with detailed patient information is needed to confirm clinical implications.