The literature describing 31P, 'H, "C, UNa and I%' MRS in vim in human cancers is reviewed. Cancers have typical metabolic characteristics in "P and 'H MRS including high levels of phospholipid metabolites and a cellular pH more alkaline than normal. These alone are not specific for cancer but are diagnostic in appropriate clinical settings. Some metabolic characteristics appear to be prognostic indices and correlation with treatment response is emerging as an important potentially cost-effective use of MRS in oncology. ' (PME) and phosphodiesters (PDE) 1, intracellular pH (pHNMR) and free cellular magnesium concentration (Mg+*). Natural abundance or enriched I3C MRS [Fig. l(b)] provides information about glycolysis, gluconeogenesis, amino acids and lipids. Water-suppressed 'H MRS [ Fig. 2(a)J shows total choline (TCHO), total creatine (TCR), lipids, glutamate, glutamine, inositols, lactate (LAC), and in brain, N-acetyl aspartate (NAA). =Na can be imaged to study its distribution within tissues. F MRS can be used to study pharmacokinetics of 5-fluorouracil(5-FU).Since 1983, when Griffiths et al. ' described 31P MRS of a sarcoma in a hand ( MS, multiple sclerosis; NAA, N-acetyl aspartate; NTP, nucleoside tnphosphate; p c , phosphocholine; PCR, phosphocreatine; PDE, phosphodiester; PE, phosphoethanolamine; PET, positron emission tomography; pHe, extracellular fluid pH; pHNMR, intracellular pH derived from the 3cP NMR spectrum; PI, phosphoinositol; PME, phosphomonoester; PMRFI, phase modulated rotating frame imaging; SE PRESS, spin echo point resolved spectroscopy; STEAM, Stimulated echo acquisition mode; TCHO, totd choline (freeechoh e , phosphocholine and other choline-containing metablltes) In. 'H MRS; TCR, total creatine (CR and PCR) in 'H MRS; TMR, ToPlcal Magnetic Resonance.MRS has been reported in over 200 brain t~m o r s .~* '~ 'H MRS of cancers outside the brain contains large signals from tissue fat making interpretation difficult and in only a few cases has water-suppressed 'H MRS been published.-'H NMR spectra without water suppression are used to examine bone marrow: since normal marrow contains 50% or more fatty tissue the ratio of the water to the methylene 'H peak is a Bottomley et al. in 1983' [Fig. l(b)) Its clinical use was established in diabetic muscle' and a 13C NMR spectrum of the prostate gland was obtained,% but only one cancer (in brain) has been reported.m23Na MRI of brain tumors, described by Feinberg et al. in 1985;' has been reported in ca 40 c a s e~.~' '~ '!T MRS was first used by Wolf er al. in 1987lO4 to examine 5-FU catabolism in the liver, and has been studied in the liver andor tumor of over 50 patients with cancer.'%"* Previous reviews of MRS in human cancers appeared in 1989.11-F'u Recent reviews of related topics include in uitro high-resolution NMR studies of cancer extracts,'= NMR studies of metabolism in tumor cells and perfused organs'24J25 and technical problems affecting reproducibility in clinical MRS.'% This paper reviews the literature of 31P, 'H, 13C, =...
