Quantification of SPECT with <sup>99m</sup>Tc-technetryl and of contrast-enhanced MRI scans in survival prognosis of patients with glial brain tumors after combined chemo – radiation treatment

Abstract

Purpose of study. The possibility of simultaneous and combined use of magnetic resonance imaging (MRI) with paramagnetic contrast enhancement (CE-MRI) and single-photon emission computed tomography (SPECT) with 99mTc-MIBI in assessing the prognosis in patients with glial brain tumors after complex chemo – and radiotherapy treatment was studied.Material and methods. Contrast-enhanced MRI of the brain and SPECT with 99mTc-Technetril were performed in 19 patients who were observed after complex chemoradiotherapy of brain tumors (gliomas of grade 3 and 4). The treatment included remote gamma irradiation and chemotherapy with temozolomide. The radiation dose was 60 Gy (30 fractions of 2 Gy × 1 once a day). The drug Temodal was prescribed in a single dose of 75 mg/sq. m. (120–140 mg) an hour before gamma therapy for up to 40 days (in a total dose of 5000–5900 mg) and in the post – radiation period according to the scheme – 6 courses of the drug for 5 days every 23 days in a single dose of 200 mg/sq.m. (280–400 mg). The total dose of Temodal for 1 course was 1400–2000 mg. In everybody, after the study, the time period of subsequent survival of patients was registered from to the primary health care data.Results. The survival time was over 20 months in case of patients after surgical removal of glial tumor and with subsequent adjuvant chemotherapy if simultaneous low values of “Tumor-to Normal Tissue” index for both 99mTc-Technetryl SPECT and CE-MRI were met, i.e. if < 1,15 for 99mTc-Technetryl SPECT and < 1,19 for CE-MRI. If index “Tumor-to Normal Tissue” was over > 1,25 99mTc-Technetryl SPECT and > 1,35 for CE-MRI then the survival time was below one year. If the “Tumor-to Normal Tissue”ratio on 99mTc-Technetryl SPECT scan was in benefit ranges whereas the on CE-MRI kept itself in high pathologic ranges the survival time was also over 19 months.Conclusion. Thus, the concomitant quantification and fusion of uptake of 99mTc-Technetryl and paramagnetic contrast agents on SPECT and MRI scans provides prognostic data on survival of patients and is worth routine use for therapy control.