I was wondering what are commonest methods of clinical examination in principles of diagnoctics for cancer?

Wow, need a book..: ..To answer but in a nutshell: we start with a good interview (including family history, exposure to toxins, etc) and a thorough physical exam. Any and all imaging studies may be used on different circumstances, from the good old x-ray to the very sensitive pet scan. All sorts of labs may be ordered depending on the situation. Ultimately, a biopsy is needed most of times to make the diagnosis.