The development of cancer takes place in stages, which are clearly defined by the medical professionals to maintain uniformity in diagnosis. In order to determine the right approach for treatment, the stage needs to be identified first. Uncontrolled division of the body's cells results in the formation of malignant tumors, which if not removed promptly, can metastasize (spread) to other parts of the body, and can invade several organs, eventually leading to death. The Stages This illness may take decades to develop. It is usually divided in 3 - 4 stages. The stage is determined, taking into consideration the original site of the primary tumor, the size of the tumor, the number of tumors, and its metastasis into the lymph nodes, nearby organs and distant organs, cell type(,) and tumor grade. Sometimes, the stages are further subdivided into sub-stages like stage 2A, 2B or 3A, 3B, etc. Here's some information on the stages of carcinoma. Taking into consideration the original site of the primary tumor, the size of the tumor, the number of tumors, spreading of it into the lymph nodes, nearby organs and distant organs, cell type and tumor grade, the stage is determined. Here, we are going to discuss 4 stages of the development of cancer. Sometimes, the stages are further subdivided into sub-stages like stage 2A, 2B or 3A, 3B, etc. Carcinoma in Situ: If this initial phase is not taken into consideration, then the development is described in 3 stages. This stage is also known as 'stage 0'. Abnormal cells (the cells which may turn into cancerous cells) are detected in the body, but they are present only in the layer of cells in which they had developed. Blood tests and imaging studies can help detect malignant growth. Stage I: This describes 'localized' cancer, wherein the tumor is in its nascent stage. The growth of tumor is restricted to the organ in which it is found. This means, the cancer has not spread beyond the primary site. It might be possible to remove it surgically, yet not always. Stage II: At this stage, the growth is described as 'regional'. Stage II suggests that the cancer has been detected beyond the primary site. The size of the tumor increases, and the number of tumors might also increase. When the disease spreads to the nearby lymph nodes, tissues or organs, it is described as 'stage II '. It is still possible to curb the growth with proper treatment. Stage III: When size of the tumor is significantly large and/or when number of tumors has increased considerably, the stage is described as stage III. During this stage, the carcinoma usually spreads to nearby lymph nodes, organs, or even to distant lymph nodes and organs. It is difficult to decide where stage III ends and stage IV starts. Stage IV: When the cancer is detected in distant organs, it is termed as 'stage IV' . At this phase, the different organs might get affected, and it becomes difficult to control it. Dealing with the very real probability of death is quite difficult. Patients are provided with drugs that help alleviate pain. Stage 4 prognosis is unfavorable, and the survival rate for this stage is very low. Regular checkups help in detecting the carcinoma in the early stages, which in turn can cause the disease to go into remission. Blood tests such as tumor marker, CA 19-9 can used as preemptive steps in understanding the stage. After the diagnostic procedures, the patient can undergo chemotherapy, radiation therapy or surgery. TNM System The description of the stage of the cancer does not help estimate the intensity. With TNM classification, doctors get an exact idea about the size, extent of the tumor, and whether it has metastasized to nearby lymph nodes, nearby organs, and distant organs. T mainly describes the size of the tumor. TX indicates that the tumor cannot be assessed, T0 indicates that there's no evidence of tumor, and Tis is used for carcinoma in situ. T1, T2, T3, and T4 (depending upon the size of the tumor) are used to describe the tumor. N represents regional lymph nodes and NX, N0, N1, N2, and N3 are used to describe the number of lymph nodes affected, and/or extent of spread of malignant growth to lymph nodes. M represents distant metastasis. MX, M0, and M1 are used to describe distant metastasis. For example: Breast cancer reported with T3 N2 M0 indicates that a large tumor (T3) that has spread beyond the breast to nearby lymph nodes (N2), but it has not yet spread to other parts of the body (M0). Thus, the staging system helps in determining a person's prognosis and appropriate treatment. Though cancer is a serious disease, affected individuals should not lose hope. Each case is unique, and there are examples of survivors of this disease. Disclaimer: The information provided in this article is solely for educating the reader. It is not intended to be a substitute for the advice of a medical expert.