Answer:
It is important to remember that statistics are just an estimation of survival, even if an evidence-based guess. There are important factors that can influence survival in this disease: your age, the location of the tumor in the brain, how much of the tumor was removed, your functional state now, and molecular alterations that predict for better survival or response to chemotherapy.
For example, if you are under age 40, have a frontal tumor, gross total removal of the tumor, are now high functioning, and have MGMT promoter methylation - these are all good. If you have some or all of these factors, your survival with additional treatment will be significantly longer than the estimated average you quoted.
If you have none of these good signs, then your question of whether to forgo therapy for better quality of remaining life is an excellent one.
For example, if you are under age 40, have a frontal tumor, gross total removal of the tumor, are now high functioning, and have MGMT promoter methylation - these are all good. If you have some or all of these factors, your survival with additional treatment will be significantly longer than the estimated average you quoted.
If you have none of these good signs, then your question of whether to forgo therapy for better quality of remaining life is an excellent one.