Cancer begins in your cells, which are the building blocks of your body. Normally, your body forms new cells as you need them, replacing old cells that die. Sometimes this process goes wrong. New cells grow even when you don't need them, and old cells don't die when they should. These extra cells can form a mass called a tumor. Tumors can be benign or malignant. Benign tumors aren't cancer while malignant ones are. Cells from malignant tumors can invade nearby tissues. They can also break away and spread to other parts of the body.
Cancer is not just one disease but many diseases. There are more than 100 different types of cancer. Most cancers are named for where they start. For example, lung cancer starts in the lung, and breast cancer starts in the breast. The spread of cancer from one part of the body to another is called metastasis. Symptoms and treatment depend on the cancer type and how advanced it is. Most treatment plans may include surgery, radiation and/or chemotherapy. Some may involve hormone therapy, biologic therapy, or stem cell transplantation.
NIH: National Cancer Institute
Cancer is a group of diseases characterized by uncontrolled reproduction and growth of abnormal cells. There are many types of cancers and they can be diagnosed through biopsy of the tumor, blood tests, bone marrow biopsy and x-rays among others. Due to the variability of types and locations, different tests are used to identify different types of cancer. A chest x-ray is commonly used in the diagnosis of lung cancer and other diseases. References 1. Cancer. MedlinePlus. URL: https://medlineplus.gov/ency/article/001289.htm. Accessed April 11, 2018. 2. Chest X-ray. MedlinePlus URL: https://medlineplus.gov/ency/article/003804.htm. Accessed April 11, 2018.
Cancer is not just one disease, is many diseases. Therefore, symptoms and their presentation differ depending on the cancer type and how advanced it is. Cancer is characterized by uncontrolled growth of abnormal cells in the body and this can occur in any organ or tissue in the body. Symptoms of cancer depend on the type and the location of cancer, some types of cancer might not have any symptoms while others might not have symptoms until the disease has reached a more advanced stage. References 1. Cancer. MedlinePlus. URL: https://medlineplus.gov/ency/article/001289.htm. Accessed April 11, 2018