Tumors can be classifed as benign or malignant. Benign tumors are simply excessive cell growths that will not cause any significant harm. Malignant tumors , that is cancers , are cell growths where the cells are replicating without any inhibition of cell growth, and they will cause death to the organism if allowed to continue growing. Here are the naming conventions used for the more common tumors. Sarcomas are cancers of connective tissues.
Leukemias are cancers of white blood cells.
Lymphomas are tumors of the lymph nodes. Osteomas are tumors of bone. Osteosarcomas are sarcomas of bone tissue. Neuromas are benign tumors of nerve tissue. Leiomyomas are benign tumors of smooth muscle tissue.