Single-incision endoscope-assisted breast-conserving surgery and sentinel lymph node biopsy: prospective SINA-BCS cohort study

The current consensus on surgical treatment for early breast cancer is to ensure oncological safety during surgery while preserving functions and aesthetics1–3. Minimally invasive endoscopic surgery has become widely used in modern surgery4–6. Endoscope-assisted surgery allows incision concealment and scar minimization, thereby optimizing aesthetic outcomes and patient satisfaction7–10. The shortcomings of endoscope-assisted surgery are, however, also prominent, including limited working space, increased surgical difficulty11, prolonged operating time, need for additional laparoscopic instruments, and increased costs9,10,12. This study describes single-incision, non-lipolytic, endoscope-assisted breast-conserving surgery (BCS) and sentinel lymph node biopsy (SLNB), the SINA-BCS technique, and compares its perioperative outcomes and cosmetic properties with those of conventional BCS and SLNB (C-BCS). This single-centre prospective cohort study evaluated the efficacy and benefits of SINA-BCS in patients with breast cancer. The study was approved by ChiECRCT (ChiECRCT20200410) and registered at Chictr.org.cn (ChiCTR2100043403). Written informed consent was obtained from all patients. Women aged 20–80 years with pathologically diagnosed cTis–2 N0 breast cancer, who were treated at the West China Hospital of Sichuan University from July 2020 to September 2022, were included. The decision to perform either SINA-BCS or C-BCS was made jointly by the patients and surgeons. Lumpectomy procedures were the same for SINA-BCS and C-BCS. Dual tracers with radioisotope and blue dye were used for SNLB. The operating space of the axilla was established using a non-liposuction method. A subcutaneous tunnel was gradually created through the lumpectomy incision, and expanded by subcutaneous dissociation of the breast tissue toward the axilla. SLNB of SINA-BCS was performed by means of polar diathermy scissors and ultrasonic scalpels, using the working space established through the subcutaneous tunnel and a specifically designed retractor system (Fig. 1). The radionucleotide probe was also inserted through the same incision to detect hot nodes. For C-BCS, an additional 3–4cm axillary incision was made for SLNB (Fig. S1).