Handbook of Genetic Counseling/Ovarian Cancer
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- Before we get started, I want to give you a chance to ask any questions or express any concerns that you may have.
- What issues do you want to make sure we discuss? What do you want to gain from our session today?
- Our plan:
- talk about your medical history and diagnosis
- discuss your family history in a little more detail
- talk about the genetics of hereditary cancers
- we'll explain what we see and discuss your risks
- talk about genetic testing - what it tests, limitations
- discuss ways for you to stay healthy
- Tell me how you got to this point. How was your ovarian cancer diagnosed?
- Fill out intake with details.
- Any other medical illnesses, surgeries, or hospitalizations?
- Update pedigree with details. A pedigree is our "physical exam". Gives us clues as to whether the cancer is hereditary. It's important to know who has AND who doesn't have cancer.
- Very specific questions about the cancer in different family members
- Age at diagnosis
- Current age & screening practices
- Age at death & specific cause of death
- Primary site of cancer (type, location, stage, laterality)
- Metastasis or any new primary cancers
- Methods of treatment/surgery
- Any types of precancerous lesions
- Ethnic background
- Environmental exposures
- Lifestyle issues (diet, exercise, stress)
- Screening habits of "unaffected" relatives
- Any other medical conditions that may be associated with cancer
- any family hx of early heart attacks, blindness, deafness, birth defects, or multiple miscarriages
- Cancer is the uncontrolled growth of cells. All cancers are genetic, but not all are inherited. It is a multifactorial disorder, caused by both genetic and non-genetic factors.
- Cancer is a very common disease. 1 in 2 men and 1 in 3 women will develop some form of cancer in their lifetimes. The most common cancer sites are lung, breast, prostate, and colon.
- In the U.S., 1 in 55 women will develop ovarian cancer (1.8% lifetime risk)
- 5-10% of all ovarian cancer is hereditary (meaning that it runs in families)
- 90% of this is caused by a BRCA1 or BRCA2 mutation
- In the U.S., 1 in 8 women will develop breast cancer over their lifetimes.
- Average age of developing cancer is 62 (2/3 of the women will be over 55)
- 5-10% of all breast cancer is hereditary. Of this, 2/3 (66%) of it is due to a BRCA1 or BRCA2 mutation
- This gene is the link between breast and ovarian cancer.
- How do we know when a cancer is hereditary? We look for clues (red flags).
- What makes us suspicious:
- more than one generation affected
- multiple close relatives affected on the same side of the family
- early age of onset (before 50)
- bilateral cancer or more than one type of cancer in the same person
- rare or unusual cancers
Genes and Chromosomes
- Hereditary cancers are caused by a change in a specific gene that is passed on
through a family
- Genes are made of DNA. They have all the instructions for how our bodies grow and develop.
- When there is a change in a gene, it causes the cell to not work properly, so it can grow out of control and become cancerous.
- Genes are packaged on chromosomes. Chromosomes come in pairs, and we inherit one from mom and one from dad.
- This gene is autosomal dominant, so only need one copy of it to inherit a higher risk of cancer. There is a 50% chance of getting it from our parents. If we carry the gene, then we have a 50% chance of passing it on.
The information in this outline was last updated in 2002.