NMR in cancer, XIII: application of the NMR malignancy index to human mammary tumours.

One hundred and nineteen specimens of human mammary tissue taken from 112 individuals, were inspected by pulsed proton magnetic-resonance techniques (at 22.5 MH2). The purpose of the study was to evaluate the diagnostic capabilities of the nuclear magnetic resonance (NMR) technique with regard to the recognition of malignancy. The combination of two NMR parameters (spin lattice (T1) and spin-spin(T2) relaxation times) into a malignancy index produced better than 95% discrimination between the 2 populations of tissue on a case-by-case basis. The mean and standard deviations obtained were 2.002 +/- 0.351 for normal tissue, and 3.137 +/- 0.667 for malignant specimens. The probability that this difference is not significant is considerably less than 0.01. In addition, specimens of fibrocystic disease and fibrous mastopathy had indices of 2.263 +/- 0.503 and 2.151 +/- 0.505 respectively. Both groups yielded P values less than 0.01 when compared to the malignant specimens.