F

False negative: Test result implying a condition does not exist when in fact it does.

False positive: Test result implying a condition exists when in fact it does not.

Familial adenomatous polyposis (FAP) fa-mil-e-uhl ad-ehn-NO-mah-tus poly-po-sis: Hereditary condition that is a risk factor for colorectal cancer. People with FAP syndrome develop polyps in the colon and rectum. These often become cancerous.

Fascia: Sheet or thin band of fibrous tissue covering muscles and some organs.

Fecal occult blood test (FOBT): Test for blood in the stool. The presence blood could be a cancer sign.

Femara: Brand name of recently FDA-approved drug for use as a "first line" treatment for metastatic breast cancer in post and pre operative protocols. Similar, but more effective than Tamoxifen at delaying tumor growth.

Fibrocystic changes: Benign changes in the breast with such symptoms as breast swelling or pain. Examiners look for the presence of nodules, lumpiness, or a discharge from the nipples. Because these symptoms (and other signs) can mimic breast cancer, a mammogram or a biopsy of breast tissue may be needed to show there is no cancer.

Fibrosis: Formation of scar-like (fibrous) tissue. This can occur anywhere in the body.

Fine needle aspiration (FNA): Procedure in which a thin needle is used to draw up (aspirate) samples for examination under a microscope. Also called . (See: Biopsy.)

First degree relative: A parent, sibling, or child.

FISH (fluorescence in situ hybridization): A physical mapping approach that uses fluorescein tags to detect hybridization of probes with metaphase chromosomes and with the lesscondensed somatic interphase chromatin.

Five-year survival rate: Percentage of people expected to survive five years or longer with a given type of cancer. Note: Advances in cancer treatment often occur quickly. Five-year survival rates, while statistically valid, may not reflect these advances. They should not be seen as a predictor in an individual case. 

Flexible sigmoidoscopy: Test to help find cancer or polyps on the inside of the rectum and part of the colon. A slender, hollow, lighted tube is placed into the rectum enabling the doctor to look for polyps or other abnormalities.

Flow cytometry: Tumor tissue test to see how quickly tumor cells are reproducing and whether they contain normal or abnormal amounts of DNA. This test is used to help predict how aggressive a cancer is. (See: Ploidy, DNA, S-phase fraction.)

Frozen section: Thin slice of tissue that has been quick-frozen and then examined under a microscope. This provides for a quick diagnosis, sometimes even while the surgeon is waiting to complete a procedure. The diagnosis is confirmed in a few days by more detailed studies - called a "permanent section". (See: Permanent section.) 

Flow cytometry: Analysis of biological material by detection of the lightabsorbing or fluorescing properties of cells or subcellular fractions (i.e., chromosomes) passing in a narrow stream through a laser beam. An absorbance or fluorescence profile of the sample is produced. Automated sorting devices, used to fractionate samples, sort successive droplets of the analyzed stream into different fractions depending on the fluorescence emitted by each droplet.

Flow karyotyping: Use of flow cytometry to analyze and separate chromosomes on the basis of their DNA content.