KEY TAKEAWAYS
- The study aimed to investigate the contemporary evidence on survival outcomes between breast-conserving surgery with adjuvant RT and mastectomy for patients with early-stage BC.
- Researchers noticed a survival advantage for breast-conserving surgery with adjuvant RT over mastectomy for early-stage BC.
Breast-conserving surgery with adjuvant radiotherapy (RT) and mastectomy have historically been considered equivalent surgical options for early-stage breast cancer (BC), largely based on randomized controlled trials (RCTs) conducted in the 1970s and 1980s. However, evolving treatment approaches and recent observational studies have suggested a potential survival advantage for breast-conserving surgery with adjuvant radiotherapy.
Kiran K Rajan and the team conducted a systematic review and meta-analysis to comprehensively evaluate the contemporary evidence regarding survival outcomes following breast-conserving surgery with adjuvant RT compared to mastectomy for women diagnosed with early-stage BC.
They performed an inclusive analysis by systematically searching MEDLINE, the Cochrane Central Register of Controlled Trials (CENTRAL), and Embase for studies published between January 1, 2000, and December 18, 2023. These studies compared overall survival (OS) after breast-conserving surgery with adjuvant RT versus mastectomy for patients diagnosed with unilateral stage 1-3 BC.
Exclusion criteria included studies focusing on neoadjuvant chemotherapy, rare BC subtypes, and specific BC populations. The risk of bias was assessed using the ROBINS-I tool, and the overall certainty of evidence was evaluated using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) tool. Studies with no critical risk of bias were included in a quantitative meta-analysis.
About 11,750 abstracts were screened, resulting in the identification of 108 eligible articles, including one article with two studies. Among these, 29 studies were excluded from the meta-analysis due to the critical risk of bias, while 42 studies were excluded due to overlapping study populations. Due to reporting incompatible results 3 additional studies were excluded.
A total of 35 observational studies provided survival data for 909,077 patients, comprising 362,390 patients who underwent mastectomy and 546,687 patients who underwent breast-conserving surgery with adjuvant radiotherapy. The pooled hazard ratio (HR) was 0.72 (95% confidence interval [CI] 0.68 to 0.75, P < 0.001), indicating improved OS for patients undergoing breast-conserving surgery with adjuvant radiotherapy. However, the overall certainty of the evidence was deemed very low.
The study concluded that there is evidence suggesting a survival advantage for women with early-stage BC undergoing breast-conserving surgery with adjuvant radiotherapy compared to mastectomy. These findings, although requiring cautious interpretation, underscore the importance of sharing them with patients to facilitate informed surgical decision-making.
The study was sponsored by the National Institute for Health and Care Research (NIHR) Biomedical Research Centre at University Hospitals Bristol and Weston NHS Foundation Trust and the University of Bristol. S.P. is an NIHR Clinician Scientist and K.F. is an NIHR Academic Clinical Lecturer. J.S. and R.W.’s time was partly supported by the NIHR Applied Research Collaboration West (ARC West) at University Hospitals Bristol and Weston NHS Foundation Trust.
Source: https://pubmed.ncbi.nlm.nih.gov/38758563/
Rajan KK, Fairhurst K, Birkbeck B, et al. (2024). “Overall survival after mastectomy versus breast-conserving surgery with adjuvant radiotherapy for early-stage breast cancer: meta-analysis.” BJS Open. 2024 May 8;8(3):zrae040. doi: 10.1093/bjsopen/zrae040. PMID: 38758563; PMCID: PMC11100524.
