Positron emission tomography with 11C-methionine in primary brain tumor diagnosis

OBJECTIVE To investigate the variations in 11C-methionine uptake in the intact brain tissue and in glial brain tumors of different types. MATERIAL AND METHODS Forty patients (21 men, 19 women) with gliomas, Grade I-IV, underwent 11C-methionine PET-CT and contrast-enhanced MRI. Standardized uptake value (SUV), tumor-to-normal (T/N) ratios and tumor volume were analyzed. RESULTS The high inter-subject variability was detected in the intact brain tissue (SUV in the frontal lobe (FL) varies from 0.47 to 1.73). Amino acid metabolism was more active in women than in men (FL SUV 1.32±0.22 and 1.05±0.24, respectively). T/N ratio better differentiates gliomas by the degree of anaplasia compared to SUV. Gliomas of Grade III (T/N=2.64±0.98) were significantly different (p