Cancer is mainly causing by unregulated cell growth. When some cells are out of order in human body, they start to grow uncontrollably and divide quicker than standard. They started to convert into malignant tumors after some stages. After growth enough, they start to invade other parts of body. Also cancer use bloodstream or lymphatic system and spread to other parts of body. Also there are some benign tumors which are not growing uncontrolled. According to researcher, there are now 200 different types of cancer in the world. Scientists divide cancer periods into stages. How many stages of cancer are there?
There are 4 stages of cancer. First stage of cancer is known as “Stage 0” Scientist call this stage as ‘in situ’ It’s the stage that some cells tend to be a tumor but all cells in this position are not converting into tumors. Some of the cells in this position poses little. Also some of them grows but don’t threat life. This stage is called as “in situ cancer” . According to researchers, it’s an important stage for early diagnosis and treatment. Also many tumor types grow only in “Stage 0” and they don’t go over.
“Stage 1” is also known as “localized cancer” because cancer tumors are only possible in some local areas in this stage and they are easier to identify. If early diagnosis and treatment of tumor is not possible, tumors grow and pass the ‘basement membrane’. It’s a thin but very important tissue boundary for the body. Because when tumor pass the ‘basement membrane’, tumor starts to invade neighboring tissues and cancer starts. Diagnosing the tumor in this stage is still early diagnosis because growing cancer cells may still not threat the life. But when invasion starts, it also starts to threat life.
Some scientists divide the Stage 2 and Stage 3 but they are commonly believed as one stage. These stages are known as “regional spread” stage If early diagnosis and treatment of cancer tumor is not possible, cells start to invade other cells and goes others. They start to go up to lymph vessel. Lymph vessels are very similar to blood vessels and they carry clear fluid. This is the last step before tumor cells goes into blood stream. In this stage, there’s a last stop of immune system. Body can detect tumor cell in lymph node and immune system starts to give a response. In some cases, immune system detects tumor cells totally and destroys all of them. This stage is called as “regional spread” because cancer cells mainly spread in one part of body and they are still not influenced the other parts.
Stage 4 is the latest stage of cancer. It’s known as “distant spread” This stage may vary from person to person. Most of the tumor cells use lymph vessels to spread over the bloodstream and goes to most distant parts of body. Also some cancer tumors invades capillary. When they invaded a capillary, they use this way to enter the bloodstream. When cancer cells totally spread into bloodstream, it’s possible to see that they form new colonies in the other parts of body. They can also spread further.
According to researcher, risk of cancer increases by age but there are only some cancer types mostly possible in children. In 2007, cancer resulted 13% of total 7.9 million human deaths in the world. There are some cancer types starting with effect of radiation or other environmental events but according to researches, averagely %7 of all cancers are hereditary and faults in gene are causing the disease.