As there are so few studies for low-grade glioma, it is noteworthy whenever anything is published. A new study on Gamma knife for low-grade glioma is being prepared for publication:
2.7cm3 (mean tumor volume in the study) is tiny for low-grade gliomas. I suspect those are the ones found accidentally (e.g., MRI done because of a car accident), rather than due to symptoms caused by the tumor.
Keep in mind that anything larger than 4 cm in diameter isn't eligible for Gamma knife, so the small average volume makes more sense when you realize the larger tumors aren't eligible.
That's not so tiny! And it also depends entirely on location; my daughter has a tumour on her hypothalamus - if that's allowed to progress to that size, then she will likely become blind.
Yep, that seems pretty tiny. Its a little unclear if what they are calling mean tumor volume is the mean residual volume, or mean initial volume. But even then it seems tiny for LGG. 2.7cm mean width would make way more sense, but that is not what it says. A typical study boundary between small and large LGG is >5cm max width. So that would be roughly over 100cm^3 is considered large.
And another side note: there were a lot of grade 1 astrocytomas included.
2,7 cm^3 volume means mean tumor width of approx. 1,7 cm, if you assume the tumor is a sphere. Volume of a sphere = (4/3)*π*radius^3, so "large" LGG with 5cm max width is approx 66 cm^3. The relation between radius and volume is ^3, so every cm makes a big difference in volume - for example if radius is 1 cm -> V=4,19cm^3, if radius is 2cm -> V=33,5cm^3.
2.7cm3 (mean tumor volume in the study) is tiny for low-grade gliomas. I suspect those are the ones found accidentally (e.g., MRI done because of a car accident), rather than due to symptoms caused by the tumor.
ReplyDeleteKeep in mind that anything larger than 4 cm in diameter isn't eligible for Gamma knife, so the small average volume makes more sense when you realize the larger tumors aren't eligible.
DeleteThat's not so tiny! And it also depends entirely on location; my daughter has a tumour on her hypothalamus - if that's allowed to progress to that size, then she will likely become blind.
DeleteYep, that seems pretty tiny. Its a little unclear if what they are calling mean tumor volume is the mean residual volume, or mean initial volume. But even then it seems tiny for LGG. 2.7cm mean width would make way more sense, but that is not what it says. A typical study boundary between small and large LGG is >5cm max width. So that would be roughly over 100cm^3 is considered large.
ReplyDeletePretty puzzling though.
Thanks for sharing that, Stephen.
ReplyDeleteAnd another side note: there were a lot of grade 1 astrocytomas included.
ReplyDelete2,7 cm^3 volume means mean tumor width of approx. 1,7 cm, if you assume the tumor is a sphere. Volume of a sphere = (4/3)*π*radius^3, so "large" LGG with 5cm max width is approx 66 cm^3. The relation between radius and volume is ^3, so every cm makes a big difference in volume - for example if radius is 1 cm -> V=4,19cm^3, if radius is 2cm -> V=33,5cm^3.