Pilot study of freshly excised breast tissue response in the 300 – 600 GHz range

Quentin Cassar,Ullrich R Pfeiffer,Laven Mavarani,Thomas Zimmer,Patrick Mounaix,Janusz Grzyb,Jean-Paul Guillet,Philipp Hillger,Amel Al-Ibadi,Gaëtan Macgrogan

doi:10.1364/boe.9.002930

Abstract

The failure to accurately define tumor margins during breast conserving surgery (BCS) results in a 20% re-excision rate. The present paper reports the investigation to evaluate the potential of terahertz imaging for breast tissue recognition within the under-explored 300 - 600 GHz range. Such a frequency window matches new BiCMOS technology capabilities and thus opens up the opportunity for near-field terahertz imaging using these devices. To assess the efficacy of this frequency band, data from 16 freshly excised breast tissue samples were collected and analyzed directly after excision. Complex refractive indices have been extracted over the as-mentioned frequency band, and amplitude frequency images show some contrast between tissue types. Principal component analysis (PCA) has also been applied to the data in an attempt to automate tissue classification. Our observations suggest that the dielectric response could potentially provide contrast for breast tissue recognition within the 300 - 600 GHz range. These results open the way for silicon-based terahertz subwavelength near field imager design, efficient up to 600 GHz to address ex vivo life-science applications.

Highlights

Ranging between far infrared and microwaves, the development of terahertz science and technology comes from both the electronic and optic sides and terahertz (THz) technology takes advantages from these two fields
In an attempt to develop a new way to detect tumor margins, we have investigated the responses of freshly excised breast tissue through 16 different samples in the 300 – 600 GHz band, using a terahertz time-domain spectroscopy (THz-TDS) system situated in a hospital
Results may suggest the ability of THz spectroscopy to differentiate the margins of both ILC and IBC from surrounding fibro glandular tissue and fat within the 300 – 600 GHz

Summary

Introduction

Ranging between far infrared and microwaves, the development of terahertz science and technology comes from both the electronic and optic sides and terahertz (THz) technology takes advantages from these two fields. The catalog of applications has increased and includes for example quality control, non-destructive testing for 3D imaging [1], spectroscopic characterization of materials [2] and chemical recognition [3]. Many of these applications rely on the unique spectral fingerprints, in the terahertz range, of chemicals and materials. The precision with which are delineated tumor margins remains weak and periodically leads to a second surgery to assess the entire breast cancer removal. Fitzgerald et al [26], were the first to investigate the ability of THz-TDS to map the breast tumor margins. Image processing techniques are studied and developed to improve the visualization of THz-images [31]

Methods

Results

Conclusion