Dictionary

blast An immature blood cell.

blast crisis A phase of advanced leukemia, usually chronic myelogenous leukemia (CML), in which the number of immature, abnormal white blood cells (blasts) in the bone marrow and blood is extremely high. Also known as the blast phase. See also leukemia.

blastoma A tumor thought to arise in embryonic tissue. This term is commonly used as part of the name for a tumor, as in glioblastoma and medulloblastoma (types of brain tumors), hepatoblastoma (a liver tumor), nephroblastoma (a Wilms tumor of the kidney), neuroblastoma (a childhood tumor of neural origin), osteoblastoma (a bone tumor), and retinoblastoma…

bleb See blister.

bleeding Hemorrhaging. Losing blood, typically because of injury to blood vessels. With simple bleeding, cleaning the site of injury and applying mild pressure or a bandage is sufficient treatment. If bleeding is caused by injury to a major blood vessel, emergency care is necessary. Spontaneous bleeding in the skin can represent a serious underlying illness…

biomarker A biologic feature that can be used to measure the presence or progress of disease or the effects of treatment. For example, prostate specific antigen (PSA) is a biomarker for cancer of the prostate.

biopsy The removal of a sample of tissue for examination under a microscope to check for cancer cells or other abnormalities.

biopsy, endometrial A procedure for sampling the lining of the uterus (the endometrium). Endometrial biopsy is usually done to detect the cause of abnormal uterine bleeding, but it may be used to determine the cause of infertility, test for uterine infections, and even monitor responses to certain medications. The procedure can be done in a…

biopsy, excisional A surgical procedure in which an entire abnormal area is removed for diagnostic examination under a microscope.

biopsy, incisional A surgical procedure in which only a portion of an abnormal area is removed for diagnostic examination under a microscope. An incisional biopsy is used when the abnormal area is too large for excisional biopsy or when excision would destroy important tissue or pose a cosmetic problem. See also biopsy, excisional.

biopsy, needle A procedure in which a small amount of tissue is taken for examination by using a hollow needle. See also biopsy; biopsy, stereotactic needle.

biopsy, punch See punch biopsy.