Cancer is a multifaceted disease requiring various treatments. Treatment decisions are made after an assessment of the tumor has been completed.
Assessing Cancer Stage
Assessments are made through the use of diagnostic imaging (e.g., PET/CT, MRI, bone scan), biopsies and other testing procedures. Based on these assessments, most cancers are classified into a staging group.
The 4-Stage System
There are usually four stages of cancer. However, it depends on which cancer you are talking about and which staging system the doctor is using. There are different ways of grouping cancers. Some staging systems have more groups and some less.
The simplest of groups include four categories of stage: in situ, local, regional and distant. Here is a brief summary of what the stages mean:
Stage 1: In Situ
Usually means a cancer is relatively small and contained within the organ in which it began.
Stage 2: Local
Usually means the cancer is localized, but the tumor is larger than in stage 1. Sometimes stage 2 means there are nearby lymph nodes that contain cancer cells.
Stage 3: Regional
Usually means the cancer is larger and cancer cells are in lymph nodes in the area.
Stage 4: Distant
Means the cancer has spread from where it started to another body organ, such as the liver, bones or lungs.
The American Joint Committee on Cancer System (TNM)
Physicians also use a staging system from the American Joint Committee on Cancer (AJCC). This staging methodology is also referred to as the TNM staging system because it is based on the size of the Tumor, Lymph Node involvement and Metastasis (spread of the disease to distant sites).