Cancer is a disease in which some of the body’s cells grow uncontrollably and spread to other parts of the body. Cancer can start almost anywhere in the human body, which is made up of numerous cells. Generally, human cells grow and multiply (through a process called cell division) to form new cells as the body needs them. Any cell of the body that are up in years or got desecrate and replaced by new cells upon cell death. At times this order of process is broken down and abnormal or damaged cells start growing. These cells form mass of tissues that forms tumours. Tumours are classified as cancerous and non-cancerous cells. Non -cancerous cells are called as benign tumours. Tumours that turn cancerous outspread into tissues and can travel into different parts of the body and form newly affected tumours, and this process is called Metastasis. This cancer affected tumours is also called as Malignant tumours. Cancer forms solid tumours in general except for blood cancer types such as Leukaemia as they do not form solid tumours in the body. The nearby tissues of the tumours are not affected benign tumours as they do not spread. Benign tumours do not grow back as they are less affecting to the body whereas cancerous tumours in rare cases do grow back. Benign tumours can be large quite sometimes and some of the benign tumours such as one that is formed in the brain can be a cause of life affecting situation.