Several different systems are used for ranking cancers by stage in the process of developing a treatment program. Staging this disease is important, because it allows a medical professional to assess it and use standardized terminology to describe it, so that the medical team can work together to develop the best course of treatment. Stages are ranked in order of severity, with slow or non-aggressive ones at the bottom of the scale, and fast-moving, severe cancers at the top.
One very common system for staging cancers runs from zero to four, with a stage zero being the least severe, while four is the most aggressive. An alternate numbered staging system is depicted in Roman numerals, with the option of I, II, III, and IV. Some physicians break the Roman numeral staging system down even further, with classifications like IIa and IIb to describe conditions that fall slightly between the stages.
Some medical professionals use the TNM system, which ranks a cancer with three separate parameters: tumor size, lymph node involvement, and metastasis. For example, someone could have a T3, N0, M1 cancer, meaning that the tumor was medium-sized, no lymph nodes are involved, and it has begun to metastasize slightly.
Other oncologists refer to in situ, localized, regional, and distant cancers when they talk about staging. In situ cancers are those that only involve a few cells, meaning that they are caught early or they develop slowly. Localized ones affect a larger area, while regional cancers are those that have begun to spread to neighboring organs and lymph nodes. In a distant cancer, it has spread to remote areas of the body, reflecting a widespread metastasis. This system is essentially interchangeable with the Roman numeral system of staging.
All types of cancer can be ranked under a staging system, including breast, colon, lung, and cervical cancers. Lower stages usually require less aggressive treatment, because the tumor is confined to a small area, and it may be able to be excised and eliminated. Higher stages require more serious treatment, and in some cases, it may be deemed untreatable as a result of how much it has spread.
Medical professionals sometimes disagree over the staging of a particular case, and seeking a second opinion can sometimes generate conflicting information. If healthcare providers do give different answers, it is a good idea for the patient to ask about why they disagree on their staging assessment, and how their treatment approaches might differ.