Other Diagnostic Tests for NHL
Imaging Studies to Diagnose NHL
After reviewed the findings from preliminary x-rays, the physician may want to conduct additional imaging studies. Computed tomography (CT or CAT scan), a computer-assisted x-ray that produces cross-sectional images of the body, and magnetic resonance imaging (MRI scan), a technique that uses electromagnets and radio waves to create computer-generated pictures of the internal organs, are particularly useful for detecting enlarged lymph nodes or lymphoma-related abnormalities of the spleen or other organs.
A newer imaging test, called CT/PET fusion imaging, combines the technology of CT scan with the technology of PET (positive emission tomography) scan. PET scans involve injecting a sugar-based radiopharmaceutical, which travels through the body and collects in organs and tissues. The PET scan is used to detect cancer cells in the body and the CT scan provides detailed images that can determine the location and size of the cancer. When the results of these tests are "fused" (brought together), the images provide more complete diagnostic information.
In addition, the physician may request a lymphangiogram, a form of x-ray in which pictures are made of the lymphatic system. The patient is injected with a special dye that helps to highlight the lymph nodes and their vessels. Imaging studies also are significant tools for the staging of HD and NHL.
Bone Marrow Tests to Diagnose NHL
If lymphoma has been diagnosed, the physician may want to sample the bone marrow to assist with cancer staging, that is, determining the extent of disease. The bone marrow is sampled by a technique known as bone marrow aspiration. During this procedure, a thin, hollow needle with a syringe attachment is used to aspirate (suction up) a teaspoon-sized sample of liquid bone marrow from the back of the hip bone. A larger needle then is employed to obtain a bone marrow biopsy (core biopsy), which removes roughly a 1/16 inch cylindrical piece of bone marrow from the hip site.
After the bone marrow samples are obtained, they are examined by many physician specialists, including a pathologist (disease diagnosis specialist), hematologist (blood specialist), and oncologist (cancer specialist). In the past, biopsy of both hip bones was standard procedure, but it now typical to perform the procedure on only one side.
Lumbar Puncture to Diagnose NHL
Lumbar puncture, also known as a spinal tap, is a procedure in which a thin needle is inserted through the lumbar (lower) backbone, below the level of the spinal cord. Cerebrospinal fluid (CSF) is withdrawn through the needle, and is then analyzed for the presence of lymphoma cells. This test is performed to see whether lymphoma has spread to the central nervous system.