Keytruda and brain mets

Posted By
4/19/2017 8:06pm
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Replies: 3


I read several posts on this forum regarding pseudo progression of Keytruda when treating the brain mets.

In case of my husband - we had 3 infusions since middle of February . MRI has been performed in March and another one yesterday. Both of them showed decease progression with multiple new lesions and size increase of some existing lesions

i have read that Keytruda effect can sometimes be delayed and enlargement of existing lesions due to swelling is also common.

But what about new lesions? Is it the decease progression and we just have to be patient and continue with Keytruda?

Or it's better to stop and switch to ipi/novo?

I know that it's case by case basis, but wanted to hear from other members of this forum.


Hi, Sorry I don't have an answer for you - but my wife is in the exact same boat. Started Keytruda two months ago after BRAF inhibitors failed. First scan showed no progress - next scan mid-May. Let me know how your husband progresses - and we can compare notes.

zfishberg - (4/25/2017 - 12:15pm)


it's good that after 2 month there are no progresses.

what about existing lesions? Did they stay the same size/increased/decreased?

regarding the combo plus a Keytruda - our oncologist suggests it as well. And we might start the Taff/Mek combo again unless it gives serious side effects as previously 

Has he had any targeted brain radiation on the lesions? I was on Pembro for 20 months. It did a lovely job stopping new lesions after the 2nd infusion... but, any and every lesion that had previously cropped up had been zapped... including those that appeared after the start of Keytruda. Brain mets like to grow in an area where the immune system is more limited than it is in the body. Anti PD1 can work in the brain, but knowing its strength lies in use of the immune system, and that immune response is somewhat decreased in the brain (it's nature's safety mechanism), having the brain lesions radiated is still considered the most effective line of treatment.