title: Using DRS during breast conserving surgery: identifying robust optical parameters and influence of inter-patient variation.
abstract: Successful breast conserving surgery consists of complete removal of the tumor while sparing healthy surrounding tissue. Despite currently available imaging and margin assessment tools, recognizing tumor tissue at a resection margin during surgery is challenging. Diffuse reflectance spectroscopy (DRS), which uses light for tissue characterization, can potentially guide surgeons to prevent tumor positive margins. However, inter-patient variation and changes in tissue physiology occurring during the resection might hamper this light-based technology. Here we investigate how inter-patient variation and tissue status (in vivovsex vivo) affect the performance of the DRS optical parameters.In vivoandex vivomeasurements of 45 breast cancer patients were obtained and quantified with an analytical model to acquire the optical parameters. The optical parameter representing the ratio between fat and water provided the best discrimination between normal and tumor tissue, with an area under the receiver operating characteristic curve of 0.94. There was no substantial influence of other patient factors such as menopausal status on optical measurements. Contrary to expectations, normalization of the optical parameters did not improve the discriminative power. Furthermore, measurements takenin vivowere not significantly different from the measurements takenex vivo. These findings indicate that DRS is a robust technology for the detection of tumor tissue during breast conserving surgery.
authors.affiliation: Netherlands Cancer Institute - Antoni van Leeuwenhoek, Amsterdam The Netherlands.
authors.forename: Lisanne L
authors.initials: LL
authors.lastname: de Boer
authors.affiliation: Philips Research, Eindhoven, The Netherlands; Biomechanical Engineering Department, Delft University of Technology, Delft, The Netherlands.
authors.forename: Benno H W
authors.initials: BH
authors.lastname: Hendriks
authors.affiliation: Netherlands Cancer Institute - Antoni van Leeuwenhoek, Amsterdam The Netherlands.
authors.forename: Frederieke
authors.initials: F
authors.lastname: van Duijnhoven
authors.affiliation: Netherlands Cancer Institute - Antoni van Leeuwenhoek, Amsterdam The Netherlands.
authors.forename: Marie-Jeanne T F D Vrancken
authors.initials: MT
authors.lastname: Peeters-Baas
authors.affiliation: Netherlands Cancer Institute - Antoni van Leeuwenhoek, Amsterdam The Netherlands.
authors.forename: Koen
authors.initials: K
authors.lastname: Van de Vijver
authors.affiliation: Netherlands Cancer Institute - Antoni van Leeuwenhoek, Amsterdam The Netherlands.
authors.forename: Claudette E
authors.initials: CE
authors.lastname: Loo
authors.affiliation: Netherlands Cancer Institute - Antoni van Leeuwenhoek, Amsterdam The Netherlands.
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Jóźwiak
authors.affiliation: Netherlands Cancer Institute - Antoni van Leeuwenhoek, Amsterdam The Netherlands; Academic Medical Center, Department of Biomedical Engineering and Physics, Meibergdreef 9, 1105AZ, Amsterdam, Netherlands.
authors.forename: Henricus J C M
authors.initials: HJ
authors.lastname: Sterenborg
authors.affiliation: Netherlands Cancer Institute - Antoni van Leeuwenhoek, Amsterdam The Netherlands; MIRA Institute, University Twente, The Netherlands.
authors.forename: Theo J M
authors.initials: TJ
authors.lastname: Ruers
keywords: (060.2310) Fiber optics; (170.6935) Tissue characterization; (300.0300) Spectroscopy