Cancer Dictionary – H
heart cancer (hart KAN-ser) A rare cancer that develops in tissues of the heart. Also called cardiac sarcoma.
hematogenous (HEE-muh-TAH-jeh-nus) Originating in the blood or spread through the bloodstream.
hematologic cancer (HEE-muh-tuh-LAH-jik KAN-ser) A cancer of the blood or bone marrow, such as leukemia or lymphoma.
hematologist (HEE-muh-TAH-loh-jist) A doctor who specializes in treating blood disorders.
hematoma (HEE-muh-TOH-muh) A pool of clotted or partially clotted blood in an organ, tissue, or body space, usually caused by a broken blood vessel.
hematopoiesis (hee-MA-toh-poy-EE-sus) The formation of new blood cells.
hematopoietic growth factor (hee-MA-toh-poy-EH-tik …) A group of proteins that causes blood cells to grow and mature.
hematopoietic tissue (hee-MA-toh-poy-EH-tik TIH-shoo) Tissue in which new blood cells are formed.
hematuria (HEE-muh-TOOR-ee-uh) Blood in the urine.
hemoptysis (hee-MOP-tih-sis) Coughing or spitting up blood from the respiratory tract.
high-dose chemotherapy (hy-dose kee-moh-THAYR-uh-pee) An intensive drug treatment to kill cancer cells, but that also destroys the bone marrow and can cause other severe side effects. High-dose chemotherapy is usually followed by bone marrow or stem cell transplantation to rebuild the bone marrow.
high-dose radiation (hy-dose RAY-dee-AY-shun) An amount of radiation that is greater than that given in typical radiation therapy. High-dose radiation is precisely directed at the tumor to avoid damaging healthy tissue, and may kill more cancer cells in fewer treatments. Also called HDR.
high-risk cancer Cancer that is likely to recur (come back), or spread.
histologic examination (HIS-tuh-LAH-jik ig-ZA-mih-NAY-shun) The examination of tissue specimens under a microscope.
histology (his-TAH-loh-jee) The study of tissues and cells under a microscope.
histopathology (HIS-toh-puh-THAH-loh-jee) The study of diseased cells and tissues using a microscope.
historic cohort study A research study in which the medical records of groups of individuals who are alike in many ways but differ by a certain characteristic (for example, female nurses who smoke and those who do not smoke) are compared for a particular outcome (such as lung cancer). Also called a retrospective cohort study.
hospice (HOS-pis) A program that provides special care for people who are near the end of life and for their families, either at home, in freestanding facilities, or within hospitals.
hypersensitivity (HY-per-SEN-sih-tih-vih-tee) An exaggerated response by the immune system to a drug or other substance.