Cancer-Related Dictionary

Oligodendroglioma is a type of brain tumor arising from oligodendrocytes, cells that produce myelin - an insulating layer around neurons. This slow-growing tumor generally affects adults and is often found in the frontal lobe of the brain. Symptoms include persistent headaches, seizures, and changes in personality or mental capacity. Treatment typically involves surgery, chemotherapy, and radiation therapy.

Oncogenes are genes that can potentially cause cancer. When they are normal, they help to regulate cell growth and division. However, when they are altered or mutated, they can lead to abnormal cell growth and proliferation, eventually fostering the development of cancer.

An oncogenic virus is a type of virus that can cause cancer by altering the genetic material of the host cells it infects. These viruses can disrupt normal cell regulation and lead to uncontrolled cell growth.

An oncologist is a specialized medical doctor who diagnoses and treats cancers. This expert is involved in the patient's care from diagnosis to treatment, utilizing therapies like chemotherapy, radiation, and surgeries to manage the disease. Oncologists often collaborate with a team of healthcare professionals to provide personalized care for each patient.

Oncology is a branch of medicine that specializes in the diagnosis, treatment, and prevention of various types of cancer. It includes medical professionals known as oncologists who use various therapies like chemotherapy, radiation, and surgery to combat cancerous cells.

An oncovirus is a type of virus that can cause cancer. This happens when the viruses alter the cell regulatory genes, leading to uncontrolled cell growth and division, which eventually forms a malignant tumor. Oncoviruses are responsible for approximately 12% of all human cancers.

Oral cancer refers to any cancerous tissue growth located in the mouth. It may arise as a primary lesion originating in any of the oral tissues, by metastasis from a distant site of origin, or by extension from a neighboring anatomic structure, such as the nasal cavity or the maxillary sinus. Early detection significantly increases the chances of a successful treatment.

Orchiectomy is a surgical procedure carried out to remove one or both testicles in males. This operation is typically utilized as a treatment method for testicular cancer or prostate cancer. The procedure can also be employed in cases of severe trauma to the testicles or as part of gender affirmation surgery.

Osteosarcoma is a type of cancer that originates in the bones. It most commonly affects adolescents and young adults, but can occur at any age. This aggressive malignant neoplasm leads to abnormal, uncontrollable growth of osteoblasts, the cells responsible for bone formation. It predominantly occurs in long bones like the femur, tibia, and humerus, consequently causing pain and swelling in the affected area.

An ovarian germ cell tumor is a type of cancer that originates from the cells in the ovaries responsible for producing eggs. These tumors are rare and primarily affect young women and adolescents. While most ovarian germ cell tumors are benign, some can be malignant and require medical treatment.

Current ovarian reserve tests include hormonal markers and ultrasonographic markers.  Hormonal markers: are determined in the blood after a blood sample is taken. Suitable markers are FSH (follicle-stimulating hormone), estradiol, inhibin-B, and antimullerian hormone (AMH).  The measurement of FSH levels at 2 or 3 days after the onset of full menstrual flow has been used as a marker of ovarian reserve since the 1980s, based on its association with reproductive outcome. Elevated FSH values are associated with but not always predictive of poor ovarian response and failure to conceive. Estradiol is the natural estrogen of the woman and is responsible for the expression of the female secondary sexual characteristics. It is produced by granulosa cells of the ovarian follicles. Estradiol levels are commonly assessed during the early follicular phase and high levels indicate normal functioning. Inhibin is a peptide hormone with 2 subunits (Alpha and Beta). Inhibin-B is produced by granulosa cells of ovarian follicles and its levels vary during the menstrual cycle. Concentrations of inhibin-B decrease with age and during premature ovarian failure. AMH is a proteohormone and is produced by granulosa cells of the follicles. AMH shows little cycle fluctuation and correlates negatively with the progression of follicle loss and with a woman's age: the higher the AMH, the higher the follicle count.  Ultrasonographic markers: include the antral follicle count (AFC) and the measurement of ovarian volume, both assessed through ultrasound of the ovaries. The AFC describes the number of antral follicles in the ovaries measuring between 2–10mm. The greatest advantage of ultrasonographic markers of ovarian reserve is their non-invasiveness. Both markers exhibit an age-related decline.

Ovarian cancer is a type of cancer that begins in the ovaries, the female reproductive glands that produce eggs or ova. It often goes undetected until it has spread within the pelvis and abdomen, making it difficult to treat and often fatal. Symptoms can include abdominal bloating, discomfort, weight loss, and frequent urination. It is the fifth most common cause of cancer-related death among women.