Application of small-angle X-ray scattering for differentiation among breast tumors.

Small-angle X-ray scattering (SAXS) is an X-ray diffraction-based technique where a narrow collimated beam of X-rays is focused onto a sample and the scattered X-rays recorded by a detector. The pattern of the scattered X-rays carries information on the molecular structure of the material. As breast cancer is the most widespread cancer in women and differentiation among its tumors is important, this project compared the results of coherent X-ray scattering measurements obtained from benign and malignant breast tissues. The energy-dispersive method with a setup including X-ray tube, primary collimator, sample holder, secondary collimator and high-purity germanium (HpGe) detector was used. One hundred thirty-one breast-tissue samples, including normal, fibrocystic changes and carcinoma, were studied at the 6 degrees scattering angle. Diffraction profiles (corrected scattered intensity versus momentum transfer) of normal, fibrocystic changes and carcinoma were obtained. These profiles showed a few peak positions for adipose (1.15 +/- 0.06 nm(-1)), mixed normal (1.15 +/- 0.06 nm(-1) and 1.4 +/- 0.04 nm(-1)), fibrocystic changes (1.46 +/- 0.05 nm(-1) and 1.74 +/- 0.04 nm(-1)) and carcinoma (1.55 +/- 0.04 nm(-1), 1.73 +/- 0.06 nm(-1), 1.85 +/- 0.05 nm(-1)). We were able to differentiate between normal, fibrocystic changes (benign) and carcinoma (malignant) breast tissues by SAXS. However, we were unable to differentiate between different types of carcinoma.