Heredity
Most forms of cancer are "sporadic", and have no basis in
heredity. There are, however, a number of recognised syndromes
of cancer with a hereditary component, often a defective tumor
suppressor allele. Famous examples are:
certain inherited mutations in the genes BRCA1 and BRCA2 are
associated with an elevated risk of breast cancer and ovarian
cancer
tumors of various endocrine organs in multiple endocrine
neoplasia (MEN types 1, 2a, 2b)
Li-Fraumeni syndrome (various tumors such as osteosarcoma,
breast cancer, soft tissue sarcoma, brain tumors) due to
mutations of p53
Turcot syndrome (brain tumors and colonic polyposis)
Familial adenomatous polyposis an inherited mutation of the APC
gene that leads to early onset of colon carcinoma.
Hereditary nonpolyposis colorectal cancer (HNPCC, also known as
Lynch syndrome) can include familial cases of colon cancer,
uterine cancer, gastric cancer, and ovarian cancer, without a
preponderance of colon polyps.
Retinoblastoma, when occurring in young children, is due to a
hereditary mutation in the retinoblastoma gene.
Down syndrome patients, who have an extra chromosome 21, are
known to develop malignancies such as leukemia and testicular
cancer, though the reasons for this difference are not well
understood.
Other causes
A few types of cancer in non-humans have been found to be caused
by the tumor cells themselves. This phenomenon is seen in
Sticker's sarcoma, also known as canine transmissible venereal
tumor. The closest known analogue to this in humans is
individuals who have developed cancer from tumors hiding inside
organ transplants.
Pathophysiology >>
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Cancer
Classification
1. Nomenclature
2. Adult cancers
3. Childhood cancers
Signs and symptoms
Diagnosis
1. Investigation
2. Biopsy
Treatment
1. Surgery
2. Radiation therapy
3. Chemotherapy
4. Targeted therapies
5. Immunotherapy
6. Hormonal therapy
7. Symptom control
8. Complementary and alternative
9. Treatment trials
Prognosis
1. Emotional impact
Causes
1. Chemical carcinogens
2. Ionizing radiation &
Infectious diseases
3. Hormonal imbalances & Immune system dysfunction
4. Heredity & Other causes
Pathophysiology
1. Epigenetics
2. Oncogenes
3. Tumor suppressor genes
4. Cancer cell biology
4.1 Clonal evolution
4.2 Biological properties of cancer cells
Prevention
1. Modifiable ("lifestyle") risk factors
2. Diet
3. Vitamins
4. Chemoprevention
5. Genetic testing
6. Vaccination
7. Screening
Epidemiology
History
Research |
