M. K. Srour1, A. Chung1 1Cedars-Sinai Medical Center,Surgical Oncology,Los Angeles, CA, USA
Introduction: BioZorb® fiducial marker (BZ) is an implantable device made of 6 clips to mark the surgical site of tissue removal in three dimensions to allow for focused radiation therapy, while allowing for tissue in-growth during the healing process with resorption by the body overtime. Current literature investigating the use of the BZ is limited and focused on its value for radiation treatment.
Objective: To investigate the feasibility and surgical complications associated with the BZ in breast conserving surgery.
Methods: From April 2015 to June 2018, 89 patients who underwent 91 partial mastectomies with planned adjuvant radiation therapy and placement of BZ were followed prospectively.
Results: 89 patients who were a median age of 59 years old (range 34 – 84) underwent 91 operations with BZ placement – 86.8% underwent a segmental mastectomy (n=79) and 13.2% underwent a breast wide re-excision for margins at the time of BZ placement (n=12) [Figure 1]. Of the 79 segmental mastectomies, 21.5% (n=17) were palpable tumors. Location of the tumor and subsequent BZ placement was most often in the upper outer quadrant (43.3%), followed by upper inner (26.8%), lower outer (22.5%), and lower inner quadrant (9.9%). 93.4% (n=85) had a single BZ placed, 4.4% (n=4) had two BZs placed in a single lumpectomy cavity, and 2.2% (n=2) had two BZs placed in separate lumpectomy cavities of the same breast. Of the 10 different tissue marker sizes used, a 2x3cm BZ was most commonly used (37/98, 37.8%), followed by 3x4cm (25/98, 25.5%), and 1x3x2 (9/98, 9.2%). 5 patients underwent immediate bilateral breast reduction following placement of the BZ. Of the 91 operations, 21 patients had a subsequent re-operation for positive margins after initial placement of the BZ, of which 86.4% retained the BZ [Figure 1]. During these re-operations, only 1 patient had the BZ removed due to discomfort (4.5%) and 2 had it removed due to subsequent mastectomy (9.1%). At a median time of 1.1 years, the BZ continued to be palpable on clinical breast exam in 63.6% of patients. The longest time that the BZ continued to be palpable was 2.8 years. Additional imaging was ordered because a clinician palpated a mass, unaware it was the BZ 8.8% of the time (n=8). 30 day complications include 3.3% of patients with an infection requiring antibiotics (n=3) and 2.2% with an abscess requiring aspiration and antibiotics without removal of the BZ. 1 patient had migration of the BioZorb® from the breast to the axilla which required surgical explant at 9 months post-op.
Conclusion: BZ is feasible to use in breast conserving surgery with few short and long-term complications, but will result in a palpable mass that may persist for more than 1 year. Explantation is rare.
