Abstract OT2-1-04: Intraoperative assessment of tumor margins with a new optical imaging technology: A multi-center, randomized, blinded clinical trial

Abstract

Abstract Background: Partial mastectomy is the most commonly performed procedure for invasive breast cancer and is associated with a reexcision rate commonly ranging from 20% to 40% in the literature. This high rate of reexcision is associated with significant additional cost (estimated over $4,000 per reexcision) and lower quality outcomes. Optical coherence tomography (OCT) is a high-resolution imaging technology that images tissue structure with micron-scale resolution – on the same scale as histopathology. It is similar to ultrasound except it uses near infra-red light waves instead of sound waves to create detailed images several millimeters deep into tissue. Although widely used in ophthalmology with growing use in cardiovascular imaging, high-resolution OCT imaging has a narrow depth of focus and requires instrumentation that is not well suited for intraoperative use. Drawing from OCT technology, interferometric synthetic aperture microscopy (ISAM) is a computational imaging technique that creates high-resolution, always in-focus images in software with basic optical instrumentation. A high-resolution ISAM probe and imaging system has been developed for intraoperative imaging of tissue structure and has the potential to broadly impact intraoperative assessment of tumor margins. Intraoperative ISAM imaging of the excised breast cancer specimen margins and in vivo imaging within the surgical cavity may reduce the high rate of reexcision associated with partial mastectomy. Trial Design: The trial design is a prospective, multi-center, randomized, double arm study comparing the reexcision rate of standard of care partial mastectomy versus the reexcision rate of standard of care partial mastectomy plus intraoperative ISAM imaging. Inclusion Criteria: Women histologically diagnosed with invasive carcinoma of the breast (invasive ductal or lobular)Undergoing partial mastectomy (lumpectomy) procedureAge 18 years or more Exclusion Criteria Multicentric diseaseBilateral diseaseNeoadjuvant systemic therapyAll T4 tumorsPrevious radiation in the operated breastPrior surgical procedure in the same quadrantImplants in the operated breastPregnancyLactationParticipating in any other investigational study which can influence collection of valid data Primary Endpoints Measure of surgical reexcision rateRate of tumor at final surgical marginsSecondary EndpointsVolume of tissue excisedClinical and economic measures of addressing asymmetry Statistical Methods: The trial is designed to show superiority of the ISAM imaging arm to the standard of care. Statistical design is two group, continuity corrected chi-squared test of equal proportions with 90% power and alpha=0.05. The trial design assumes a baseline reoperation rate in the standard of care arm of 24% with at least a 50% reduction in the ISAM imaging arm. Present Accrual and Target Accrual Not yet recruiting. Target accrual is 230 patients in the partial mastectomy + imaging arm and 230 patients in the standard of care partial mastectomy arm. Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr OT2-1-04.