31P magnetic resonance spectroscopic profiles of neoplastic human breast tissues.

Phosphorus-containing metabolites of human breast tissues from malignant, benign, and noninvolved breast parenchymal specimens were examined by using techniques of perchloric acid extraction and 31P magnetic resonance spectroscopy. Twenty-four separate resonances arising from the established phosphorylated metabolites of high-energy- and low-energy-phosphate intermediary metabolism were identified and quantitated. Subsequent to magnetic resonance spectroscopic analysis, the data from the three tissue groups were compared and contrasted on a statistical basis by using Scheffé simple and complex contrast procedures. Theories of tumor metabolism and biochemical interactions were invoked, including the tissue high-energy-/low-energy-phosphate modulus, the phosphomonoester/Pi ratio, and 10 other metabolic indices. The data demonstrated the ability of 31P magnetic resonance spectroscopy to differentiate among the three tissue groups. Both benign and malignant tumors demonstrated comparable Warburg effects. Phosphomonoester metabolism was shown to be altered in neoplastic tissues relative to the noninvolved tissues. Phosphocreatine was elevated in benign tumors. This elevation in phosphocreatine plus a parallel elevation in an uncharacterized phosphate resonating at a chemical shift of 3.66 delta permits the important differentiation between malignancy and benignancy in human breast disease. The tissue energy modulus indicated that benign tissue is relatively more aerobic than noninvolved tissue and significantly more aerobic than malignant tissue.