World Brain Tumour Day 2018 is on June 8 Brain tumour is a life threatening medical condition which is caused by the abnormal growth of brain cells. Not all tumours are cancerous. There are two main types of brain tumours—noncancerous(benign) and cancerous(malignant). Brain tumours are usually graded depending on how fast they grow and what are the chances of it growing back. Noncancerous(benign): Noncancerous tumour are those tumours that grows slowly and they are less likely to grow back. Thus they are known as low-grade tumours (grade one or two). Cancerous(malignant): These tumours either start in the primary area i.e.