Pilot trial assessing the feasibility of intra-ductal delivery of epirubicin (epi)-containing nanoparticles (NP) via InDuct@ Breast Microcatheter (IDBM)

828 Background: Over 95% of breast cancers (BC) originate in the epithelial cells lining the breast duct. We piloted the use of the IDBM as a targeted drug delivery tool to infuse epi-containing NP into the breast duct. Methods: Epi, a naturally fluorescent anthracycline, was encapsulated into biodegradable NP (diameter < 1μ), which could then be suspended in saline for injection. Informed consent was obtained from women with planned mastectomies. In the operating room, the mastectomy was performed and the tumor specimen was removed for pathologic assessment. Via the IDBM, 3–5 ml of NP (200 mg/ml suspended in saline), containing 6% epi, were injected into a breast duct that had been previously marked with vital blue dye. The duct was dissected, frozen intact, and subsequently “step-sectioned”. Sections were examined by fluorescent microscopy to assess presence of intact NP within the ductal lumen. “Success” was defined as the presence of intact NP within the lumen of the distal one-third of the dissected ...