Cell-to-Disease Map

Cells combine to form tissues, and abnormal new growth is a neoplasm. A tumor can be benign or malignant; cancer is malignant disease, and cancer that has spread to another site is metastatic.

Pathology studies disease and examines cells and tissues. Necrosis means tissue death. Sepsis is a dangerous whole-body response to infection; it should never be reduced to the casual phrase "blood infection." The immune system and white blood cells help defend against microbes such as bacteria and viruses.