Cavity Shaving in Breast Conserving Surgery for Breast Cancer Patients
Condition: Breast Cancer
MeSH terms: Breast Neoplasms
Study type: Interventional

Summary: 
      This randomized controlled trial is to evaluate the impact of additional cavity shaving (CS)
      on pathological cavity margin (CM) status in breast cancer patients. Patients receiving
      standard breast-conserving surgery (BCS) will be randomized to intra-operative CM assessment
      versus intra-operative CS followed by CM assessment. The primary objective of this study is
      to assess the impact of CS on intra-operative CM status, intra-operative re-excision rate,
      post-operative CM status and re-excision rate, cosmetic outcomes, and on intraoperative time
      and medical costs.
    

Detailed description: 
      After stratified and blocked randomization, the patients' name, admission ID and treatment
      assignment will be written on a slip of paper, and will be placed in a sealed envelop. A
      label with the patients' name and admission ID will be placed on the sealed envelop, which
      will be kept in a locked file. On the day of surgery, a research coordinator will bring the
      sealed envelope to the operation room. During the standard-of-care BCS, the tumor was excised
      with a rim of grossly normal tissue. Additional resections are allowed when any of the
      margins of the tumor-containing specimen were suspected to be inadequate on the basis of
      standard gross evaluation by surgeons. Prior to intra-operative CM assessment, the research
      co-ordinator will unseal the envelop and determine which procedure has been designated to the
      patient. The cosmetic outcome and the quality of life will be evaluated at the day of
      discharge, after completion of radiotherapy and one year by the patient herself, her partner
      and a research co-ordinator.
    

Intervention name(s): Cavity shaving; Standardized BCS+CM assessment.
Intervention type(s): Procedure; Procedure
Intervention description(s): Resect the residual cavity circumferentially (superior, inferior, medial, lateral) and the thickness of the cavity shaving depends on the surgeon's discretion (Recommended 0.5-1.0cm). The principles of the cavity shaving includes: 1) do not compromise the cosmetic outcomes; 2) covers the entire cavity;; For standardized BCS(Chen K, et al. Ann Surg Oncol. 2012), we resect a rim of 1 cm macroscopically normal tissue around the tumor. The anterior and posterior margins of the tumor-containing specimen extended up to the subdermal plane of the skin and down to the pectoralis major fascia, respectively. The anterior and posterior CMs assessment will not be needed. A surgical blade was used for resecting the CMs (superior, inferior, medial and lateral) to render the thickness of the CMs as thin as possible. No procedures were required for distinguishing the inner and outer surface. They were then frozen and cut parallel, but not perpendicular to the largest surface area. CMs were defined as positive when in situ or invasive carcinoma was found intraoperatively by frozen-section analysis.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single (Participant)
Primary purpose: Treatment
Keywords: breast-conserving surgery(BCS); Cavity shave margin; Proportion of positive margins