Abstract P4-02-03: Breast biopsy histology relationships with opto-acoustic imaging of breast masses
Authors: van de Vijver M , Lavin PT , Stavros AT 
Published: March 2017

Abstract
Purpose: The Imagio® breast imaging system, a diagnostic opto-acoustic (OA) imaging device bearing the CE Mark, is in the U.S. FDA Premarket Approval process. OA provides both functional (relative oxygenation/de-oxygenation) and anatomic (angiogenesis) information that is co-registered and temporally interleaved in real time with gray-scale ultrasound that may improve distinction between benign and malignant masses. OA imaging pathology correlation was performed to elucidate the histologic features of OA features of breast cancers.
Methods and Materials: A multicenter postmarket surveillance and clinical follow-up study was conducted in five Dutch sites in which 209 women with breast masses underwent OA prior to biopsy. Histopathology examination of the biopsies revealed 146 benign masses (mostly fibroadenomas) and 76 malignant masses (mostly invasive ductal carcinomas). For invasive ductal carcinomas, histologic grade and the features used to assess histologic grade (nuclear pleomorphism, tubule formation, and mitotic count) were assessed. For each mass, 5 pre-determined OA features, 3 internal features, and 2 external features were evaluated. The 3 internal scores (vessels, blush, and hemoglobin) and 2 external features (capsular boundary zone and peripheral boundary zone) were separately and collectively summed for testing relationships with traditional histopathology measures using a two-sided Jonckheere-Terpstra test of ordered outcomes. Distribution differences between benign and malignant masses were performed using a Wilcoxon Rank Sum test for each internal, external, and summed total internal, external, and total score.
Results: The mean differences were significantly higher for malignant vs. benign for internal vessels (p=0.0009), internal blush (p=0.0085), external boundary zone (p&lt;0.0001), and external peripheral zone (p&lt;0.0001), but not internal hemoglobin. Mean Total Internal Score, Total External Score, and Total Internal and External Score were all significantly higher (all p&lt;0.01) for malignant vs. benign. Among invasive carcinomas, Total Internal Score and Total Internal and External Score were significantly higher for higher histologic tumor grade (p=0.04, 0.02), significantly higher Total External Score and Total Internal and External Score for higher tubule score (p=0.06, 0.03), slightly higher Total Internal Score and Total Internal and External Score for higher nuclear pleomorphism score (p=0.04, 0.05), and slightly higher Total Internal Score for higher mitotic score (p=0.03).
Conclusion: OA feature summary scores appear to differentiate between benign vs. malignant and correspond to histologic grade and scoring components of histologic grade. The U.S. investigational PIONEER pivotal study (n=2,095) may further confirm these results.
Citation Format: van de Vijver M, Lavin PT, Stavros AT. Breast biopsy histology relationships with opto-acoustic imaging of breast masses [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P4-02-03.