Diagnosing Head and Neck Cancer
Sentinel Lymph Node Biopsy
In certain cases, we may perform a sentinel lymph node biopsy to determine if the cancer has spread to the lymph nodes. During a sentinel lymph node biopsy, radioactive dye is injected and used to identify the sentinel lymph node, the first lymph node to which cancer is likely to spread from that tumor. In some cases, there can be more than one sentinel lymph node. The sentinel lymph node or nodes are removed and tested to determine if the cancer has spread.
Radiology to Diagnose Head, Neck and Skull Base Cancers
Radiology or imaging is a critical part of the diagnosis and treatment process for patients with head, neck and skull base cancers. Many patients seen at Froedtert & the Medical College of Wisconsin have been diagnosed somewhere else and referred to us because of our expertise in treating these complicated cancers. With a variety of imaging options at our fingertips, we have the tools to diagnose and treat our patients quickly and effectively.
- PET/CT — PET/CT combines positron emission tomography (PET) with a high-quality CT scanner in one machine. A PET scan is a nuclear medicine study which detects the metabolism of a tumor. The PET scan uses a glucose solution “labeled” with a radioactive tracer. The glucose goes to the most metabolically active areas, and tumors tend to be very metabolically active. So, even if a tumor might be hard to see in other scans, the PET scan can detect its metabolic activity. The patient can have both scans (PET and CT) done on the same table, which improves accuracy, and the images can be quickly fused to create a more comprehensive picture of the tumor.
PET/CT is especially effective when the primary tumor is unknown, when dealing with adenopathy (abnormal lymph nodes), and when evaluating for metastatic disease (cancer that has spread from somewhere else). The PET/CT scan is also helpful after treatment to see how the tumor is responding to treatment and to evaluate recurrence in certain situations.
- 64-Slice Multidetector CT – The latest CT (computed tomography) technology available, the 64-slice multidetector CT, allows clinicians to take very high quality, thin section images very quickly. Known as the LightSpeed VCT, or volume CT, this scan gives a highly detailed look at the anatomy, and can be especially effective in detecting head, neck and skull base cancers. The VCT also allows technicians to do more with images in post processing. The images can be reformatted in any plane, creating images that are helpful for planning surgical and radiation therapy treatments.
Froedtert & the Medical College of Wisconsin have three dedicated, specially trained technologists working in a separate 3-D computer workroom. These skilled technologists do all of the post work on the VCT studies, and can produce a higher level of processing. They work closely with physicians to highlight important anatomy and produce detailed views. This allows the physicians to answer specific questions and develop optimal therapies.
- MRI – Magnetic resonance imaging (MRI) plays an important role in diagnosing head, neck and skull base cancers. MRI can effectively differentiate soft tissue, map the extent of tumors and evaluate the spread of a tumor along nerves. When tumors spread into the skull, MRI is superior for evaluating the extent of that spread. Froedtert & the Medical College of Wisconsin have a 3 Tesla MRI scanner, the highest field strength used in clinical practice. (The tesla is the unit used to measure the strength of a magnetic field.)
Each of these imaging options has different, complementary strengths and each plays an important role in diagnosing head, neck and skull base cancers. Some patients may have all three kinds of scans at different points in their evaluation, treatment and follow-up care. Our extensive radiology choices are an example of our commitment to offering the latest technology available.