Spectroscopic tools for the elucidation of disease specific changes in breast cancer

Summary form only given. Microcalcifications are the unique early marker of breast cancer. However, the relationship between their occurrence and malignancy is still unknown. Vibrational spectroscopy techniques are label-free and chemically specific. They have been used to characterize these calcifications based on their composition, e.g. content of carbonates, phosphates and proteins. The first step of the study was to characterise standard minerals with different percentage of carbonate substitution and their spectral signatures in breast calcifications (hydroxyapatite, calcium oxalate) by Attenuated Total Reflection (ATR) FTIR spectroscopy and Raman micro-spectroscopy (Fig. 1). Then, the second step was to determine the carbonate content and the carbonated calcium hydroxyapatite amount in breast tissue by using micro-FTIR imaging. These data will be used to elaborate a predictive model based on Partial Least Square-Discriminant Analysis (PLS-DA) classification in order to determine the level of carbonate substitution in each breast biopsy microcalcifications and any correlation with pathology. Novel mid-IR source and detector technologies are also being explored to develop rapid imaging methods that may be suitable for clinical diagnostics.