Changes of ³¹P-MR Spectroscopy in Experimental Tumors Following Radiotherapy Combined with 5-Fluorouracil Compound (UFT)

抄録

OHKUBO, M. Changes in ³¹P-MR Spectroscopy in Experimental Tumors Following Radiotherapy Combined with 5-Fluorouracil Compound (UFT). Tohoku J. Exp. Med., 1993, 169 (3), 215-223- The energy metabolism of FM3A tumors in C3H mice following radiotherapy (20 Gy or 40 Gy), 5-fluorouracil compound (UFT) chemotherapy or radiotherapy (20 Gy) combined with UFT was investigated by in vivo ³¹P-MR spectroscopy on day 2 after treatment. The effects were compared with the growth curves of the tumors and with the cytokinetic and histological changes in the tumors on day 5 after treatment. The combined group (20 Gy+UFT) showed growth curves similar to the 40 Gy group. Cytokinetic and histological changes of the combined group were also similar to those of the 40 Gy group, suggesting supra-additive effect of UFT. ³¹P-MR spectra of the combined group were similar to those of the 40 Gy group which were characterized by increase of intracellular pH(pHi), decrease of Pi/β-NTP and of PME/totalphosphorus -signal ratios. Spectra of the UFT group and the 20 Gy group, on the contrary, showed decrease of pHi, increase of Pi/β-NTP and of PME/totalphosphorus -signal ratios. Changes detected by ³¹P-MR spectroscopy on day 2 were considered to reflect early metabolic events which were correlated to the growth curve, cytokinetic and histological alterations observed on day 5 after treatment.- ³¹P-MRS; experimental tumor; irradiation; UFT