which blood test is the best to check for cancer

just wanted to know which blood test can confirm or is/are almost accurate if you have cancer in the body,

i know there are blood tests to specify certain cancers in certain areas for example the prostrate in men to have a PSA blood test, so the blood test i want to know about is a test that simply tells you if there's cancer in the body or not.

i have heard  cea,crp,esr, fbc u &e (i know other conditions then cancer can give positive results on these) if they are negative would that almost cross out cancer? Anyone have anymore ideas,
or do blood tests not gints of cancer in anyway?

[glycojim]

I know of one test that has relevance to specific cancers.  It is a serum beta 2 microglobulin (B2M); easy blood test.  It is used as a cell surface marker in leukemia / lymphoma / multiple myeloma; also in some kidney situations; also in HIV; elevated levels can indicate cancer and it is on the move.

[glycojim]

Forgot to mention, I was diagnosed with CLL 5 years ago

[peteranjane]

thanks for the reply,

i will have a look into that, (b2b(, thank you very much, wanted to know what blood tests my husband could have to check for colon cancer apart from a colonscopy

so far the below results were normal
cea,crp,esr, fbc u &e,psa