What are the chances of surviving brain tumor after it has been treated?

Depends . Difficult to answer as it depends on multiple factors. Prognosis for primary brain tumors is based on tumor type and grade, patient's performance status, patient age. Rpa prognostic index. Curran wj et al. J natl cancer inst. 1993 may 5;85(9):704-10. Prognosis for metastatic age, kps, ecm, number of brain mets. Sperduto pw, int j radiat oncol biol phys. 2009 nov 24. Hope that is helpful.
Depends. Unfortunately your question is difficult to answer without knowing the kind of brain tumor you had and the extent of the tumor's effects in you brain and whether radiation &/or chemotherapy was used adjunctly. Many tumors can be removed fully and have great prognoses, whereas others may be too malignant and carry an extremely poor prognosis. Hopefully that helps.