<s>[INST] A friend of mine was diagnosed with stage 4 cancer... she said she has a tumor on her brain and a small lesion on her lung.  She said the brain tumor is not cancer, but the lung is and that the dr. was calling it stage 4 because she has 2 tumors..   Is that an accurate statement or is there something she isnt clearly understanding.  (really a friend of mine, not me) [/INST] Dear Friend.It's nice to see your concern for your friend. We would be able to tell you accurately if you could send us the Scans done. But for your query purpose, I can tell you that lesions at 2 different places can be because of metastasis. Tumour from one organ can spread to others through blood, lymphatics or direct contact. So it might be possible that she has metastatic growth in her brain. A PET scan would help. Hope she gets well soon. ChatDoctor </s>