A tumour 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.
Premalignant tumours are tumours that are not yet cancerous but gruadually developing properties of 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.