While the location of the tumor dictates the prognosis, treatment and severity of the cancer, these generalized stages of adenocarcinoma give an idea of the way in which doctors categorize the disease:
- Stage 0: the tumor is malignant, but has not spread
- Stage 1: the tumor is only present in the original organ (this stage may be separated into many stages depending on the organ)
- Stage 2: The cancer has invaded other organs, likely the lymph node
- Stage 3: The cancer has invaded other organs. This stage differs in definition according to the location of the cancer.
- Stage 4: The tumor has spread (metastasized) to organs farther away from the original affected organ. This may make it inoperable.
While the stages of adenocarcinoma vary depending on the location of the tumor, all stages use the TNM tumor staging system. In this system, the cancer is rated according to these three factors:
- T – Tumor is rated on its size/extent
- N – Nodes denotes the involvement of the lymph nodes
- M – Metastases indicates whether the tumor has spread