Prediction of nuclide accumulation spread based on the volume of enhancing magnetic resonance imaging lesion in glioblastoma patients.

Background: 11C-methionine-PET (MET) and Thallium-201 chloride-SPECT (TL) are useful for predictive proliferation ability and tumor invasion range identification in glioma patients, however they are not always possible in any hospital or country. Our study aimed to assess whether the range of MET and Tl accumulation could be predicted from the contrast-enhanced lesions in Gadolinium (Gd)-T1 weighted magnetic resonance image in glioblastoma multiforme (GBM) patients.

Methods: In 25 cases, the MET-area, TL-area, O-area where MET and TL overlap, and all accumulation area (AA-area) were measured in the same axial cross section as the Gd enhanced maximum area (Gd-area). This tracing operation was repeated with all axial fusion slices, and each volume was also measured (Gd-V, MET-V, TL-V, O-V, AA-V).

Results: The maximum accumulation distance of MET and TL beyond the Gd-area was limited to within 30 mm, 35 mm, respectively. Significant positive correlations were showed in all combinations with Gd-area: MET-area (r=0.851, P<0.0001), TL-area (r=0.955, P<0.0001), O-area (r=0.935, P<0.0001) and AA-area (r=0.893, P<0.0001), respectively. All combinations with Gd-V showed significant positive correlation: MET-V (r=0.867, P<0.0001), TL-V (r=0.952, P<0.0001), O-V (r=0.935, P<0.0001) and AA-V (r=0.897, P<0.0001), respectively.

Conclusions: Approximate tumor volume Gd-V can be calculated using the formula A * B * C / 2, where A, B, and C represent the dimensions of Gd-enhanced lesion in 3 axes perpendicular to each other. The nuclide accumulation predictive table created using the obtained linear approximation functions can be used to predict the average tumor invasion range from the Gd-V without preoperative nuclear examinations.