Go back to the index of this complete glossary to find the definition of all medical terms for cancers, treatments and health.
Cancer Glossary - O
- Omaya reservoir : A device which is surgically inserted under the scalp for
direct injection of chemotherapy throughout the spinal fluid. Drugs can be administered
into the reservoir, rather than through the back during a spinal tap.
- Oncology : The branch of medicine that studies cancer or malignant diseases.
An Oncologist is a doctor who treats cancer.
- Oligodendroglioma : A type of brain tumor.
- Oophorectomy : Removal of the ovaries.
- Ophthalmoscope : A lighted instrument used to examine the
inside of the eye, including the retina and the optic nerve.
- Optic nerve : The nerve that carries messages from the retina to the brain.
- Orchiectomy : surgical removal of testicles.
- Osteosarcoma : Cancer of the bone that is most common
in children. Also called osteogenic sarcoma.
- Ostomy : Operation to create an opening from an area inside the
body to the outside. See colostomy.
- Ovaries : The pair of female reproductive organs that produces eggs (ova) and hormones. They are located in the lower abdomen, one on each side of the uterus.