Mathematical modeling via the fast Padé transform (FPT) is applied according to experimental NMR data encoded from (a) normal,
non-infiltrated breast tissue, (b) benign pathology (fibroadenoma) and (c) malignant breast tissue. At a partial signal length
N
P
= 1500, the FPT provided exact reconstruction of all the input spectral parameters for the time signals corresponding to
the normal, benign as well as to the malignant lesions. The converged parametric results remained stable at longer signal
lengths. The Padé absorption spectra yielded unequivocal resolution of all the extracted physical metabolites, even of those
that were nearly completely overlapping (phosphocholine and phosphoethanolamine at 3.22 ppm). The capacity of the FPT to resolve
and precisely quantify the physical resonances as encountered in normal versus benign versus malignant breast is demonstrated.
In particular, the FPT unambiguously delineated and quantified diagnostically important metabolites such as lactate, as well
as choline, phosphocholine and glycerophosphocholine that are very closely overlapping and may represent MR-retrievable molecular
markers of breast cancer. This was achieved by the FPT without any fitting or numerical integration of peak areas. We conclude
that these advantages of the FPT could be of definite benefit for breast cancer diagnostics via NMR and that this line of
investigation should continue with encoded data from benign and malignant breast tissue, in vitro and in vivo. We anticipate
that Padé-optimized MRS will reduce the false positive rates of MR-based modalities and further improve their sensitivity.
Once this is achieved, and given that MR entails no ionizing radiation, new possibilities for screening/early detection open
up, especially for risk groups, e.g. Padé-optimized MRS could be used with greater surveillance frequency among younger women
with high breast cancer risk.
Keywords Breast cancer - Magnetic resonance spectroscopy - Time signals - Quantification - Fast Padé transform