Volume localized in vivo proton MR spectroscopy of breast carcinoma: variation of water-fat ratio in patients receiving chemotherapy

Results are reported on in vivo volume localized proton magnetic resonance spectroscopy (MRS) of patients (n = 44) suffering from carcinoma of the boa st, using a bilateral boast surface coil. Localized proton MR spectra of th e unaffected contralateral breast of these patients are dominated by resona nces arising from fat and are similar to the breast tissue from normal volu nteers (controls, n = 13), while in the malignant breast tissues the water resonance dominates. On the other hand, the water suppressed proton MR spec tra of malignant breast tissue reveal several metabolites of low concentrat ion including the choline peak around 3.2 ppm and other resonances attribut able to purine and pyrimidine nucleotides, in the 8.5 ppm region. Elevated water-fat (W-F) ratios are measured in the malignant tissues, compared with the normal breast tissue of controls and from the contralateral unaffected breast tissue of the patients (n = 11). In the case of patients receiving chemotherapy resulting in the reduction of primary tumor size, the W-F rati o shows a statistically significant (P < 0.01) decrease compared with the p re-therapy value, thus providing a non-invasive indicator of favourable cli nical outcome of neoadjuvant chemotherapy for locally advanced breast cance r. The method provides the potential for non-invasively monitoring and asse ssing the response of breast cancer to neoadjuvant chemotherapy. (C) 1998 J ohn Wiley & Sons, Ltd.