In vivo phosphorus-31 magnetic resonance spectroscopy of normal and pathological breast tissues.

In vivo phosphorus-31 magnetic resonance spectroscopy, at 1.5 T, in addition to magnetic resonance imaging and mammography, was performed on the breast tissue of 59 subjects, using a 40 mm or 80 mm surface coil for spectral localization. The patients were divided into three groups: Group 1, 46 control subjects; Group 2, nine patients with breast carcinoma; Group 3, four patients with benign breast disease. The relationship of age, menopausal status, breast size and pattern, use of contraceptive pill and history of breast disease to spectral characteristics of breast tissue was examined for the control group. In multivariate analysis, only menopausal status and age were found to be significantly related to tissue biochemistry. Pre-menopausal women had reduced phosphocreatine (PCr) (%) (p = 0.02), and increased phosphomonoesters (PMEs) and beta-nucleotide triphosphate (beta-NTP) (%) (p = 0.05), while the fat-to-water ratio was higher in older women (p = 0.02). No significant differences were identified between the control subjects and the patients with benign breast disease. When spectra from patients with breast carcinoma were compared with an age-matched volunteer group, alpha- and gamma-NTP (%) were found to be higher in the cancer tissue (p less than 0.01 and p = 0.01, respectively), while PCr (%) was reduced (p less than 0.01). The ratio beta-NTP:PCr was higher in the carcinoma group of patients (p less than 0.05). In vivo phosphorus-31 magnetic resonance spectroscopy is a non-invasive examination which may prove useful in the early differentiation of malignant breast disease from normal and benign conditions.