TNM system for esophageal cancer
The stages of esophageal cancer are assigned based on The American Joint Committee on Cancer’s (AJCC) TNM system, a commonly accepted method based on three key components:
- Tumor (T) describes the size of the original tumor.
- Node (N) indicates whether the cancer is present in the lymph nodes.
- Metastasis (M) refers to whether cancer has spread to other parts of the body.
A number (0-4) or the letter X is assigned to each factor. In esophageal cancer staging, as in all cancer staging, a higher number indicates increasing severity. For instance, a T1 score indicates a smaller tumor than a T2 score. The letter X means the information could not be assessed.
Once the T, N and M scores have been assigned, an overall stage is assigned.