Wednesday, 25 January 2017

How common is it for GBM to metastasize to other parts of the brain?

3 comments:

  1. A good source of information on this is a study called "Evaluation of pseudoprogression rates and tumor progression patterns in a phase III trial of bevacizumab plus radiotherapy/temozolomide for newly diagnosed glioblastoma" published online last August. This study was based on patients in the phase 3 AVAglio trial in which patients were randomized to upfront Avastin or placebo combined with standard radiochemotherapy.

    Table 3 of the study shows that out of 333 patients in the placebo arm (no Avastin), 64.6% had "local" (single focus) tumors at baseline and at progression, 18.9% had multifocal tumors at baseline and at progression, 9% had local tumors at baseline which became multifocal at recurrence, 4.5% had local tumors which recurred in a distant location (but were not multifocal). So altogether 13.5% had local tumors at baseline which recurred as either multifocal or distant recurrences. About the same percentage (~10%) in the Avastin arm went from local tumor at baseline to multifocal/distant recurrence.

    "Distant" in this study was defined as "a single new focus of enhancement or nonenhancing tumor centered outside a 30 mm margin around the primary site or margin of the resection cavity." 30 mm = 3 cm. Recurrence at a far distant site in the brain is probably even less common.

    http://www.brainlife.org/fulltext/2016/_Wick_W160811.pdf

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    1. Mike - would you mind dropping me a line at logan607 at hotmail? I'm in this exact same situation as of this week and would like to trade notes if at all possible. Thanks!

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  2. Regarding extracranial metastasis, there are only few surveys. Some papers suggest are very rare occurrence of 2% outside the CNS, but glioblastoma are expected to metastasize in 10-25% of the cases inside the CNS. This might be of importance to longterm survivors

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