Small-angle x-ray scattering studies of human breast tissue samples

Abstract

Small-angle x-ray scattering (SAXS) patterns are recorded from thin breast tissue samples containing healthy and cancerous regions. The SAXS patterns are compared with histo-pathological observations. The information available from SAXS is reviewed, and a model for scattering from collagen is presented. Scattering patterns of collagen at regions far from the tumours are essentially different from those at tumours. The axial period of collagen fibrils is 65.0 +/- 0.1 nm in healthy regions, and 0.3 nm larger in cancer-invaded regions. The average intensity of scattering from cancerous regions is an order of magnitude higher than the intensity from healthy regions. This is interpreted to arise from an increase of the specific surface area of the scatterers, which is due to a disruption of the molecular and supra-molecular structures in cancerous regions and invasion of new types of cells. The differences of the SAXS patterns are large and distinctive enough to suggest that these phenomena may be utilized in mammography.

Response to P. Suorttiet al.'s and K. D. Rogerset al.'sComments onSynchrotron fibre diffraction identifies and locates foetal collagenous breast tissue associated with breast carcinomaby V. J. James (2002).J. Synchrotron Rad.9, 71–76

“…Since the ®brillar collagen is aligned along the ducts, the quality of the images was much improved when compared with earlier samples taken from other sections of the breast or from random biopsy material. We found that a certain deterioration occurred to some samples when stored in liquid nitrogen as were the samples studied in the report of Ferna  ndez et al (2002). Such samples still gave a pattern but the patterns were not as sharp.…”

Model predictions for the wide-angle x-ray scatter signals of healthy and malignant breast duct biopsies

“…There are two regimes of interest: small-angle x-ray scatter (SAXS) (x < 0.1 nm −1 ) [21][22][23][24][25][26][27][28] for studying supramolecular structures and wide-angle x-ray scatter (WAXS) (0.5 nm −1 < x < 5 nm −1 ) 29-41 conventionally used to study crystallographic structures. The momentum transfer variable x ¼ sinðθ∕2Þ∕λ combines the dependence of scatter on x-ray wavelength (λ) and scatter angle (θ).…”

X-ray dark-field imaging modeling

“…Moreover, carcinoma invasion is accompanied by destruction as well as synthesis of fibrillary and nonfibrillary matrix proteins. The tumor growth induces density fluctuation on the micrometer and submicrometer scale and small-angle scattering behaviors of tumors are significantly different from that of healthy tissues [5][6]. Hence, x-ray dark-field imaging is able to reveal detailed structural features in soft tissues and offers a superior contrast resolution for characterization of cancerous tissues.…”