Can lung cancer resist treatment and move to the brain?

Unfortunately Yes: Both of the common types (non-small cell type or small cell type) very often spread into the brain. The rate of spread ranges from 20-50% depending on type and stage of cancer.

You bet!: There are 100k brain metastasis per year, and lung cancer patients compose about half of them. It is a very common first site of relapse, and can have serious consequences. Preventitive brain radiotherapy is indicated in all responders in small cell, but the trial in non-sclc showed reduction in frequency of brain metastases, but no survival benefit. Thus, many insurers will not pay for it.