Fallopian tubes (fa-LO-pee-in): Part of the female reproductive tract. The long slender tubes through which eggs pass from the ovaries to the uterus.

Familial dysplastic nevi (fa-MI-lee-yul dis-PLAS-tik NEE-vye): A condition that runs in certain families in which at least two members have dysplastic nevi (atypical moles) and have a tendency to develop melanoma.

Familial milial polyposis (pah-li-PO-sis): An inherited condition in which numerous polyps (tissue masses) develop on the inside walls of the colon and rectum. It increases the risk for colon cancer.

Fanconi anemia: A rare and often fatal inherited disease in which the bone marrow fails to produce red blood cells, white blood cells, platelets, or a combination of these cells. The disease may transform into myelodysplastic syndrome or leukemia. Also called Fanconi's syndrome.

Fanconi's syndrome: A rare and often fatal inherited disease in which the bone marrow fails to produce red blood cells, white blood cells, platelets, or a combination of these cells. The disease may transform into myelodysplastic syndrome or leukemia. Also called Fanconi anemia.

Fatty acids: A major component of fats that are used by the body for energy and tissue development.

Faelopment: A major component of fats that are used by the body for energy and tissue development.

Fazarabine: An anticancer drug that belongs to the family of drugs called antimetabolites.

Fenretinide: A drug being studied for cancer prevention; it belongs to the family of drugs called retinoids.

Fentanyl: A narcotic opioid drug that is used in the treatment of pain.

Fertility (fer-TIL-i-tee): The ability to produce children.

Fetus (FEET-us): The unborn offspring from the end of the 8th week after conception (when the major structures have formed) until birth.

Fiber: The parts of fruits and vegetables that cannot be digested. Also called bulk or roughage. Fiber may be effective in preventing cancer.

Fibroid (FYE-broyd): A benign smooth muscle tumor, usually in the uterus or gastro gastrointestinal tract. Also called leiomyoma.

Fibrosarcoma: A type of soft tissue sarcoma that begins in fibrous tissue, which holds bones, muscles, and other organs in place.

Fibrosis: The growth of fibrous tissue.

Filgrastim: A colony-stimulating factor that stimulates the production of neutrophils (a type of white blood cell). It is a cytokine that belongs to the family of drugs called hematopoietic (blood-forming) agents. Also called granulocyte colony-stimulating factor (G-CSF).

Filgrastim-SD/01: A substance that is being studied for its ability to increase numbers of white blood cells in people who are receiving chemotherapy. It belongs to the family of drugs called colony-stimulating factors.

Filler: An inactive substance used to make a product bigger or easier to handle. For example, fillers are often used to make pused to make pills or capsules because the amount of active drug is too small to be handled conveniently.

Finasteride: A drug (Proscar) that is used alone or in combination with another medication (doxazosin [Cardura]) to treat benign prostatic hypertrophy (BPH, enlargement of the prostate gland).

Fine-needle aspiration: The removal of tissue or fluid with a needle for examination under a microscope. Also called needle biopsy.

FK463: An antibiotic/antifungal drug used to treat infection.

Flavopiridol: Belongs to the family of anticancer drugs called flavinols.

Flecainide: A drug that is used to treat abnormal heart rhythms. It may also relieve neuropathic pain, the burning, stabbing, or stinging pain that may arise from damage to nerves caused by some types of cancer or cancer treatment.

Floxuridine: An anticancer drug that belongs to the family of drugs called antimetabolites.

Flt3L: A drug that increases the number of immune cells and may stimulate the immune system to kill cancer cells.

Fluconazole: A drug that treats infections caused by fungi.