Friend just diagnosed with mixed glioblastoma... stage 2. surgery removed 90% tumor. what could his prognosis be like?

Not clear: Not certain if you mean glioma-grade 2. By definition, if you say glioblastoma (gbm), that is grade 4. There is a big difference in prognosis. Gbm have a mean survival of 14 months with maximum surgery, radiation and chemotherapy, although there are many surviving 3-4 years with newer treatments. With grade 2, the average survival is on the order of 10-12 years depending on molecular markers.