Localized in vivo proton spectroscopy of renal cell carcinoma in human kidney

In order to obtain proton magnetic resonance spectra from the renal tumor in human kidney we performed localized magnetic resonance spectroscopy using a saddle-type flexible surface coil. Five patients biopsy-proven as renal cell carcinoma at different stages were put in supine/lateral position to minimize motion artifacts while acquiring the spectrum. Water-suppressed 1H spectra were obtained with localized stimulated echo acquisition mode (STEAM) (20/13.7/2200; TE/TM/TR) and point resolved spectroscopy (PRESS) (288/2200; TE/TR) sequences. The principal resonances in the tumor STEAM spectrum were sorbitol (3.85 ppm), trimethylamines (TMA) (3.25 ppm), two unidentified signals (2.8 and 2.2 ppm), and lipid (0.9-1.8 ppm). In the PRESS spectrum using a long echo time (288 ms), two well localized signals, TMA at 3.25 ppm and lactate at 1.35 ppm were observed from a patient with a tumor at advanced stage. Interestingly only TMA at 3.25 ppm was observed from the patient with a low grade tumor. The spectral patterns of the tumor patients were different from those of normal kidney.