My Choice v Oncologists Choice

Hey people, im new here and a first time poster so please bare with.

After draining an empyema doctors found a cancer mass, after a lot of hassle and messing around from doctors, I.E originally it wasn't cancer, then it was (apparently a ultrasound missed the mass) i was fitted with a stoma for a bowel obstruction and given a colonoscopy.

Numerous mris and ct scans later didnt 100% prove cancer but rather a high grade dysplasia, but also a mri showed a solitary liver met (which I know in terms of mets is great news) so this clearly indicates stage 4.

I was sent home and told a flexible sigmoidoscopy would be arranged, this happens tomorrow. Today I had a conversation with a clinical nurse who all but confirmed cancer, telling me they're sure it's 99.9% cancer, and they're hoping to cure.

My issue is, she also also told me they want to start chemo and surgery in the future to cut part of the liver and eventually the bowel, however, after doing months of research (I originally went into hospital early april and researched since) myself I have decided I would prefer a non-sugery approach, by combining capecitabine pills and SBRT, as opposed to their more aggressive approach.

I suffer anxiety as well as agoraphobia so that treatment plan suits me much better (even though I know id have to.leave home for the SBRT). Do you think I should advocate for this or go along with what im told?

Also to compound matters further, despite an already flexible sigmoidoscopy and the colonoscopy (tomorrow is a 2nd sigmoidoscopy) they still dont hage enough tissue for a biopsy result.

Should i tell them to use what they already have in terms of getting tissue or is there an alternative route I can take..such as blood tests or something 

Apologies if in wrong forum. 

Many thanks