Because cancer is a complex disorder that often progresses over long periods of time -- including long periods before an actual diagnosis can be made -- it is very useful to medical practitioners to identify various stages in the progression of the disease. Diagnosis may occur as the result of presenting complaints that cause a patient to seek medical help, or diagnosis may occur when routine check-ups lead to a suspicion by a physician or a laboratory specialist that a more thorough investigation is indicated. Indeed, one of the reasons why certain procedures are included in routine annual physicals is because these tests result in a diagnosis at sufficiently high rates to make them worth conducting. As medical technology advances, the procedures are modified accordingly -- and sometimes the frequency standards for these procedures are modified, as well.
The nomenclature used to indicate the progression of cancer growth and spread is quite easy to understand, remember, and communicate. Basically, the nomenclature uses the first letter of the feature that is being measured or gauged, and then adds a second letter -- or sometimes a number -- to relay additional information to the medical practitioners who will develop a treatment plan. The system of nomenclature also provides a very important method for tracking and communicating changes -- not only at the time when a patient is first seen for the disease, but also as interventions are carried out.
The TNM staging system is the most commonly used approach to staging. The TNM staging system is reviewed and revised as needed every 6 to 8 years as advances in cancer treatment are made ("American Cancer Society," 2014). The TNM system describes the tumor, the node, and metastases of each cancer ("American Cancer Society," 2014). The letter T. stands for tumor and is used to describe the original tumor and any growth into nearby tissues. The letter N. stands for node and it is used to indicate if the cancer has spread to nearby lymph nodes. The letter M. stands for metastasis and is used to tell whether the cancer has spread to other more distant parts of the body. Within the T. category, tumor size is described in terms of centimeters (21/2 cm = about 1 inch) or millimeters (10 mm = 1 cm). The letters TX mean the tumor can't be measured. The letters TO mean that there is no evidence of a primary tumor: the original tumor can't be found. The letters Tis indicate that the cancer cells are growing only in superficial layers of tissue and that it is not growing into deeper tissue; Tis also stands for in situ or pre-cancer. Numbers just after the T. describe the tumor size or amount of spread; the higher the T. number, the larger the tumor and/or the more it has spread, according to this configuration: T1, T2, T3, and T4.
The N. category describes the extent to which the cancer may have spread into nearby lymph nodes ("American Cancer Society," 2014). The letters NX means the nearby lymph nodes can't be evaluated. The letters N0 means that the nearby lymph nodes do not contain any cancer. Numbers just after the N. describe the size, location, and number of lymph nodes involved; the higher the N. number, the more lymph nodes contain cancer, according to this configuration: N1, N2, N3, and N4.
The M. category tells if there are distant metastases, a term that means the cancer has spread to other parts of the body ("American Cancer Society," 2014). The letters MX means metastasis can't be evaluated ("American Cancer Society," 2014). The letters M0 means that no distant cancer spread was found. The letters M1 mean that the cancer has spread to distant organs or tissues; that is, distant metastases were found in the body. It is important to recognize that each type of cancer has its own version of the classification system; therefor, the letters and numbers will not always stand for the same condition in each type of cancer.
The values for T, N, and M. are combined in order to assign an overall stage. The conventional stage groups are stage I through stage IV, with the Roman numeral IV standing for the most cancer present than in the lower numbered stages ("American Cancer Society," 2014). Also, the stages may be further subdivided by letters A and B. Stage 0 means the cancer is at a very early stage, has not spread, and is confined only to the area of the primary tumor; this is also called carcinoma in situ. Stage I cancers are the least advanced and often carry a good prognosis. Although more advanced stage cancers are also treated, the prognosis is usually not as good as for cancers in the lower stages ("American Cancer Society," 2014).
Some cancers are also given a grade in a process called differentiation, which is a measure of how abnormal the cancer cells appear under the microscope ("American Cancer Society," 2014). Grade can be an indicator of severity since cancers cells that look more abnormal also tend to spread and grow faster ("American Cancer Society," 2014). The grade is assigned a number from 1 to 4 ("American Cancer Society," 2014). Cancer cells with lower numbers look more like normal tissue than do cancer cells with higher numbers ("American Cancer Society," 2014). Cancer cells that are higher grade typically have a worse prognosis and may require different types of treatments than low-grade cancers ("American Cancer Society," 2014). The grade of a cancer can affect the treatment and the prognosis even when it does not change the stage of the cancer ("American Cancer Society," 2014).
Some cancers use a different grading system. For instance, prostate cancer is assessed using a Gleason score, which is a composite assigned to the two areas that contain most of the cancer ("American Cancer Society," 2014). Added together, these number make up the Gleason score -- a number from 2 to 10 ("American Cancer Society," 2014). For some sarcomas, the grade is based on differentiation and the numb er of cells that appear to be dividing, and how much of the tumor consists of dying tissue ("American Cancer Society," 2014). These attributes provide information about the speed of the cancer growth and how quickly the cancer is likely to spread ("American Cancer Society," 2014).
The type of cell that makes up a cancer is also important since the type of cancer cell can affect the outlook, the treatment, and the staging determination ("American Cancer Society," 2014). For instance, cancers in squamous cells and in adenocarcinoma cells are staged differently ("American Cancer Society," 2014). The location of a tumor may also affect the outlook and is a factor in staging ("American Cancer Society," 2014). For example, cancer of the esophagus is staged differently depending on where in the esophagus the cancer is located: upper, middle, or lower third ("American Cancer Society," 2014). Tumor marker (prostate specific antigen or PSA) levels also affect stage determination in prostate cancer.
Complications Of Cancer and Side Effects of Treatment
The complications of cancer and the treatment of cancer include the following: Pain, fatigue, difficulty breathing, nausea, diarrhea or constipation, weight loss, chemical changes in the body, brain and nervous system problems, unusual immune system changes (paraneoplastic syndromes), low blood count, anemia, bleeding, lymphedema, and fatigue ("Mayo Clinic," 2014).
Medical clinics and hospitals that treat cancer patients are aware of the delicate balance that must be achieved between treatment of the disease and maintenance of the bodily systems. Aggressive treatments of some disease have given way to more moderate treatments or to combinations of treatments that have less overall negative impact on the physiology of the patients receiving treatment.