NMR studies of tumours

31p nuclear magnetic resonance (NMR) spectra have been obtained from animal and human tumours grown in laboratory rodents. The tumour cells are only slightly more acid than the surrounding muscle but they tend to have large Pi and sugar phosphate peaks, suggesting anoxia, and large but variable phosphodiester peaks. The results indicate that NMR will be an important tool for studying tumours in the laboratory, and for their diagnosis, assessment, and monitoring in clinical practice.