How do we diagnose Colorectal Cancer?
Since early diagnosis is key, we perform screening examination to find the polyps as early as possible.
CT colonography, sometimes called CT Colonoscopy (CTC) or Virtual Colonoscopy (VC). This can be done purely as a screening exam or on those who have failed an optical colonoscopy exam or are at increased risk for complications from optical colonoscopy. Low-radiation CT images of the abdomen and pelvis are obtained after the large bowel is gently inflated with carbon dioxide. Subsequently, special software is used to create a 3-D images of the bowel. Specialist radiologists then interpret these images and reconstructions to find polyps and other abnormalities. This information can be provided to your doctor for further evaluation if necessary.
If tumor is found then the following examinations can be performed to “stage” (determine the extent of) the disease.
PET-CT (Positron Emission Tomography and Computed Tomography): We can tag a special molecule with a small amount of radioactive material, inject it into the body and then scan the body to detect cancer. This gives us an idea of where and how extensive the cancer is, either at the time of diagnosis or to determine if a particular treatment is having an effect.
MRI: High-resolution images of the abdomen and/or pelvis are obtained without radiation, using a combination of magnetic field and radio-frequency pulses. This is very helpful for accurate detection of cancer (particularly of the rectum). At Mecklenburg Radiology, we prioritize patient comfort and use high strength magnets to obtain this study – a rectal coil is therefore not necessary. We also often use MRI of the liver to detect if disease has spread to that order with high accuracy.
Regular CT (or CAT scan): Can be used in combination with the above exams to scan the body and determine areas of abnormality. This is the workhorse study in the vast majority of cases, and offers a very good overview of the disease process.