Economic impact of omitting sentinel lymph node biopsy in early breast cancer: a secondary analysis of the randomized venus trial

Abstract

Introduction: The omission of sentinel lymph node biopsy (SLNB) in early breast cancer patients who are clinically node-negative has been explored. However, data regarding the economic implications of this strategy remain limited. The VENUS trial is designed to evaluate SLNB omission. Objective: This report presents a preplanned secondary endpoint consisting of a cost analysis comparing SLNB with ultrasound-based axillary staging. Methods: This prospective, multicenter, non-inferiority randomized controlled trial included patients with T1–2, cN0 (clinical and ultrasound), M0 breast cancer, randomized to SLNB or no axillary surgery. A cost comparison was conducted between the two staging strategies: surgical and imaging-based. The surgical approach included lymphoscintigraphy, SLNB and histopathological analysis. The imaging-based strategy consisted of axillary ultrasound with percutaneous biopsy and histopathological evaluation of suspicious lymph nodes. Costs were calculated using Brazilian reimbursement systems (SIGTAP/DATASUS and TUSS/CBHPM) and expressed in US dollars (USD). Results: A total of 713 patients were included: 371 imaging-based and 342 surgical. Ultrasound-based staging was associated with substantially lower costs. In the public system, the cost per patient was USD 12.24 in the imaging group versus USD 158.48 in the surgical group (92.3% reduction), whereas in the private system, costs were USD 84.06 versus USD 391.20 (78.5% reduction), respectively. Surgical staging was 12-fold more expensive in the public system and 4.3-fold in the private system. In a subgroup analysis aligned with the American Society of Clinical Oncology (ASCO) and the National Comprehensive Cancer Network (NCCN) guidelines for SLNB omission (age ≥50 years, T1, G1–2, estrogen receptor/progesterone receptor positive, human epidermal growth factor receptor 2 [HER2]-negative), costs per patient were 13.8-fold higher in the public system and 4.8-fold higher in the private system. Conclusion: Axillary ultrasound-based staging demonstrates a substantial economic advantage over surgical staging in both public and private healthcare systems, with a more pronounced benefit observed in the public setting.