A typical cancer diagnosis begins with an unusual symptom. The doctor will ask you about your medical history and any symptoms you are experiencing. He will also order tests to determine the cause of your symptoms. Unfortunately, many people with cancer have no symptoms. In these cases, cancer is diagnosed during a medical test for another problem. Screening tests for cancer are important because they can detect the disease in otherwise healthy people. Mammograms and colonoscopies are two common screening methods.

A cancer cell begins with a normal cell that is not mutated. The normal cells in our bodies divide and die and replace themselves with new ones. When cancer cells don’t get the signal to apoptosis, they continue to divide and form a tumor. A tumor can be benign or malignant, depending on its characteristics. A malignant tumor can invade nearby tissues and spread to other parts of the body. In these cases, a treatment plan may not be effective.

Infections are another cause of cancer. Infections are responsible for up to 18% of all cancer deaths, ranging from 25% in Africa to just 10% in the developed world. Viruses are the usual culprits, but bacteria and parasites are also responsible for cancer. Taking measures to prevent or treat a cancer infection should be the first line of defense against this type of disease. It is important to note that most people with cancer have no family history of the disease.

A tumor develops when a normal cell breaks down. A tumor’s DNA is broken down, causing a mutation that makes it unable to survive. When cancer cells become resistant to these processes, they spread to other areas of the body. These abnormal cells eventually turn into a tumor and can invade nearby tissues and spread to other parts of the body. Despite these complications, many people are cured of cancer. The best cancer treatment strategies are a combination of chemotherapy and lifestyle changes.

While the cause of cancer is unknown, it is believed to be the result of a gene mutation. These mutations allow the cancer to escape the body’s repair systems. By dividing without stopping, cancer cells can become resistant to various treatments. The mutation can even make it difficult to distinguish the original source of the tumor. This is why the disease is so difficult to treat. While cancer is a highly contagious disease, it can be prevented.

Cancer starts in a cell. In order to cause a tumor, a cell must be large enough to form a centimeter-sized mass. The tumor must also contain at least one million cells in order to be considered a cancer. For these reasons, a cancer must grow to a centimeter in size before it can be diagnosed as a tumor. Luckily, these types of cancers are more common than you might think.