Many of the test results (as described in the diagnosing hypopharyngeal cancer section) are used to determine the extent, or stage, of the cancer. The stage of cancer describes how much cancer is in the body. It helps your doctor understand the seriousness of the cancer, how best to treat it, and what the chance of survival is.
For hypopharyngeal cancer, doctors mostly depend on the TNM system created by the American Joint Committee on Cancer (AJCC). The TNM system is based on three key pieces of information:
- How big the main tumor (T) is
- If the cancer has spread to nearby lymph nodes (N)
- The spread (metastasis) to distant parts of the body (M)
Numbers or letters after T, N, and M provide more details about each of these factors. Lower numbers mean that the cancer is in an early stage. Higher numbers mean the cancer is more advanced.
The standardized stages of hypopharyngeal cancer are:
- Stage 0 - abnormal cells in the top layer of cells lining of the hypopharynx that may become cancer.
- Stage 1 - cancer is only in one part of the hypopharynx and is no more than two centimeters.
- Stage 2 - tumor is between two and four centimeters and has grown into more than one part of the hypopharynx or it has grown into a nearby area; it has not spread to nearby lymph nodes or to distant parts of the body.
- Stage 3 - tumor is larger than four centimeters or it is affecting the movement of the vocal cords or it has grown to the esophagus; or it has spread to a single lymph node on the same side of the neck.
- Stage 4A - cancer has spread to the cartilage around the thyroid or trachea, bone under the tongue, the thyroid, or nearby soft tissue; spread to one lymph node on the same side of the neck (larger than three but smaller than six centimeters).
- Stage 4B - cancer spread to the muscles in the upper spinal column, carotid artery, chest cavity lining, and/or lymph nodes (any size).
- Stage 4C - any size tumor has spread to other parts of the body.