Comparison of Local Recurrence Outcomes between Breast Conservation Therapy and Mastectomy for the Treatment of Breast Cancer among Young Women: A Systematic Review and Meta-Analysis.

Abstract

Background: Recent clinical trials comparing local recurrence rates in young breast cancer (BC) patients after breast-conserving therapy (BCT) versus mastectomy are limited. The local recurrence (LR) rate in young BC patients is notably higher than in other age groups, whether the recurrence rates after the two surgical options are comparable remains unclear. This meta-analysis aimed to assess the safety of BCT and mastectomy for young age BC patients by comparing LR rates between the two procedures.

Methods: We conducted a systematic search of four electronic databases (Medline, PubMed, Cochrane Library, and Web of Science) for relevant studies comparing LR rates in BC patients aged 40 years or younger who were treated with BCT or mastectomy. Studies that met the inclusion criteria were synthesized using a random-effects model, with a primary focus on LR rates. Sensitivity analyses and meta-regression were performed to evaluate bias and heterogeneity, ensuring a thorough assessment of the available evidence.

Results: Among the 2,936 studies screened, 10 studies encompassing 9,215 patients were included, with 5,236 undergoing BCT and 5,803 undergoing mastectomy. The summary odds ratio (OR) indicated a significantly greater risk of LR for BCT compared to mastectomy among young BC patients (OR = 1.48; 95% CI: 1.12-1.96). In subgroup analysis, the BCT group exhibited a higher 5-year LR rate (OR = 1.67; 95% CI: 1.13-2.46) compared to the mastectomy group. This trend persisted across tumor stages, with the BCT group showing an increased LR risk in both the T1-2 (OR = 1.84; 95% CI: 1.44-2.36) and T1-4 (OR = 1.74, 95% CI: 1.50-2.03) stages. Nodal status analysis indicated a higher LR risk for BCT in the N0-1 (OR = 2.549, 95% CI: 1.79-3.46) stages. Among very young women (aged ≤35), the difference in LR rates between BCT and mastectomy was even more pronounced (OR = 2.04, 95% CI: 1.47-2.82).

Conclusion: Our meta-analysis found that young BC patients undergoing BCT had a significantly higher risk of LR, with a 48% increased risk compared to those who underwent mastectomy (OR = 1.48; 95% CI: 1.12-1.96). This difference was even more pronounced in patients aged 35 years or younger. While the elevated LR risk with BCT in young patients is well documented, individualized treatment planning should weigh this against potential survival advantages and quality-of-life preservation.