Studies of human tumors by MRS: A review

Abstract

The literature describing ³¹P, ¹H, ¹³C, ²³Na and ¹⁹F MRS in vivo in human cancers is reviewed. Cancers have typical metabolic characteristics in ³¹P and ¹H 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. ¹⁹F MRS examines pharmacokinetics of 5‐fluorouracil and by demonstrating its retention predicts response of a cancer to treatment. Current needs include improvement of diagnostic specificity by use of techniques like multivoxel MRS, proton decoupling of ³¹P, short echo time and fat‐suppressed ¹H MRS, ¹³C MRS direct or via ¹H‐observe, and statistical analysis of multiple spectral features. Trials in large populations in well defined clinical settings are needed to determine if MRS can provide independent prognostic indices useful in cancer management.