Tumour
A tumour[1] is formed by accelerated cell cycle which leads to uncontrollable growth of cell. This results into abnormal growth of mass tissue with no purposeful function. Tumour is also referred to as neoplasm. Tumours can either be benign, premalignant or malignant.
Benign Tumours
Benign tumours are not cancerous tumours and do not invade surrounding tissue. Despite not being cancerous they can be harmful if they are pressing on blood vessels or nerves.
Premalignant Tumours
Premalignant tumours are tumours that are not yet cancerous but gruadually developing properties of malignant tumours.
Malignant Tumours
Malignant tumours are cancerous tumours. These tumours metastasise and invade surrounding tissue. One key feature of malignant tumours is that they divide uncontrollably.