Articles/clinical trials testing new therapies versus Saltz Regimen [the current gold standard]:
MedLinePlus only has illustrations of colon/colorectal cancers and staging [III - lymph node involvement]. For x-ray and other diagnostic imaging, suggest you try a CME [Continuous Medical Education] site designed for radiologists/radiation oncologists. The only CME I'm familiar with that occasionally includes x-ray images is at emedicine. Another option is med school radiology/radiation oncology departments - try the larger schools [Harvard, Yale, UCLA, Tufts, U. Penn, etc.]. Otherwise case studies.