Radiography has been the foundation for cancer screening for many years. Its accessibility and generally lower cost makes it often the first step of imaging when screening for cancer. Although it is very useful in screening for cancer, it is often followed by more precise diagnostic imaging if any areas of concern are found. Radiography is also used in clinical staging of cancer to determine the instance of distant metastasis.
Computed Tomography (CT)
Computed Tomography scans (CT Scan) can be used to locate and measure tumors that may not be able to be fully visible through radiographs. CT allows for slices of the patient to be rendered as an image. This allows the doctor interpreting the results to identify certain tissues without obstruction from bones, muscles, or fluids. CT is generally more sensitive than radiography, and can generally provide a more detailed image of the tumor suspected.
Ultrasonography can be used to determine the extent of localized tumors. Ultrasounds can be useful diagnostic tools when evaluating areas where fluid may interfere with radiographic images/content. In fact, it is now become commonplace as the first choice of diagnostic imaging for abdominal evaluation. Ultrasonography can also be a useful tool for guidance in obtaining biopsies or fluids for flow cytometry.
Magnetic Resonance Imaging (MRI)
Magnetic Resonance Imaging can be used to acquire well-defined soft tissue images/content. Unlike the CT, which only takes “slices” of the area being imaged, an MRI can allow the veterinarian to view the area of concern from any plane. Magnetic Resonance images/content are especially helpful for cancer patients where neurologic involvement is a concern.