Phenobarbital (Anticonvulsant

At a Glance

Cancer and tumors occur when normal controls on cell growth and repair fail, allowing abnormal cells to multiply and survive. Some tumors form localized masses that are benign, while malignant tumors are cancers that can invade and spread. Not all cancers create a discrete lump; blood and lymphoid cancers can involve bone marrow, blood, or lymph nodes without a single solid mass.