Rong Tang
Massachusetts General Hospital, USA
Title: A New Method for Intraoperative Breast Specimen Imaging at Massachusetts General Hospital-Micro-computed Tomography (Micro-CT)
Biography
Biography: Rong Tang
Abstract
Intraoperative specimen imaging is commonly performed to confirm complete excision breast lesions, but has false positive
and false negative rates that lead to incorrect specimen assessment in 21-44% of cases.Micro-CT provides non-invasive,
highly quantitative imaging in small specimens within a few minutes.We explored the use of micro-CT for intraoperative
assessment of a variety of breast specimens.
Excised breast specimens, including lumpectomy specimens, shaved cavity margins(SCM), mastectomy specimens and
axillary lymph nodes, were evaluated with a table top micro-CT scanner, Skyscan 1173 (Skyscan, Belgium), with a 40-130kV,8W
X-ray source. Scanning for 7 minutes and reconstruction for another 7 minutes provided desired resolution in breast specimens.
In lumpectomy specimens, micro-CT could clearly visualize orienting sutures and see the location of tumor masses and
associated calcifications relative to specimen margins. In separately excised cavity margin specimens, micro-CT visualized
tumor masses and calcifications that indicated the need for additional tissue excision. Micro-CT provided detailed images
of axillary lymph nodes and their vessels’ 3D structure. 103 SCM from 26 lumpectomies were scanned and compaired with
histopathology results. Margin status by micro-CT was concordant with histopathology in 86/103 (83%) SCM. Micro-CT
had 73% sensitivity, 85% specificity, 46% positive predictive value, and 95% negative predictive value of SCM. 5/26(19%) case
required a re-excision based on the final margin status, micro-CT could identify 3 out of these 5 cases intraoperatively.
Micro-CT is a potentially useful tool for assessment of breast cancer specimens, allowing real-time analysis of breast
lumpectomy specimens or cavity shaved margins.