Spectral differences in the 31P NMR of normal and malignant tissue.
High-resolution 31P NMR spectra of normal and malignant muscle tissue from mice were obtained at 100 MHz. The spectrum of normal muscle was found to resemble that obtained by Hoult et al. for normal rat skeletal muscle. But the spectrum of malignant muscle tumor (rhabdomyosarcoma) was found to comprise only the inorganic phosphate and sugar phosphate peaks, which indicates potential usefulness of this NMR method for diagnosis. Moreover, the inorganic phosphate peak was observed to be shifted downfield 70 Hz from the location seen in normal muscle. This identification of an NMR absorption frequency different in cancer tissue than in normal, singles out what may be the first of many absorption frequencies that could be utilized as target frequencies for delivery of cancer-destructive radiation.