Hereditary Cancer Clinic

A patient must meet the current provincial guidelines for offering mutation analysis of BRCA1 and BRCA2 and must meet either of the following criteria:

1) Patient is currently receiving treatment for breast cancer. Expedited testing would allow the patient and her doctor the option of proceeding with prophylactic mastectomy, instead of radiation therapy, if she is found to carry a BRCA1 or BRCA2 mutation. If mastectomy is chosen, the patient can avoid unnecessary radiation and have the full range of options for reconstructive surgery.

And, the patient’s surgery or radiation therapy is to begin no sooner than 8 weeks from the date of blood draw, and before the results are expected, based on the current TAT for testing in the province.

Please note: this criterion excludes elective reconstruction and/or prophylactic surgery
as a reason for expedited testing, unless it is being done at the same time as surgery to treat
the patient’s cancer

2) Patient requires surgery for other urgent medical reasons (eg. A hysterectomy for uterine bleeding causing anemia) and may use the information to alter surgical decisions (eg. salpingo-oophorectomy to be done with hysterectomy).

And, the patient’s surgery is to take place no sooner than eight weeks from the date of blood draw, and before the results are expected, based on the current TAT for testing in the province.

Please note: this does not include unaffected patients who want to make a decision about prophylactic surgery only.

• Multiple cases of breast cancer (particularly where diagnosis occurred at less than 50 years) and/or ovarian cancer at any age in the family — especially in closely related relatives in more than one generation.
• Age at diagnosis of breast cancer less than 35 years.
• A family member diagnosed with both breast and ovarian cancer.
• Breast and/or ovarian cancer in Jewish families.
• Family member or members with primary cancer occurring in both breasts — especially if one or both cancers were diagnosed before age 50.
• A family member diagnosed with invasive serous ovarian cancer.
• Presence of male breast cancer in the family
• Family member with an identified BRCA1 or BRCA2 mutation
• Presence of other associated cancers or conditions suggestive of an inherited cancer syndrome

Please note: Ovarian cancer includes cancer of the fallopian tubes and primary peritoneal cancer.

At least one case of cancer:

• Ashkenazi Jewish and breast cancer under 50 years, or ovarian cancer at any age. Note: testing limited to ethnic specific mutations, unless other criteria given in this list are met.
• Breast cancer at less than 35 years
• Male breast cancer at any age
• Invasive serous ovarian cancer at any age

At least two cases of cancer on the same side of the family with:

• Breast cancer at under 60 years, and a first or second-degree relative with ovarian cancer or male breast cancer
• Breast and ovarian cancer in the same individual, or bilateral breast cancer with the first case under 50 years.
• Two cases of breast cancer, both under 50 years, in first or second degree relatives
• Two cases of ovarian cancer, at any age, in first or second degree relatives
• Ashkenazi Jewish and breast cancer at any age, and any family history of breast or ovarian cancer. Note: testing limited to ethnic specific mutations, unless other criteria given in this list are met.

At least three cases of cancer on the same side of the family:

• Three or more cases of breast or ovarian cancer at any age.

Testing for unaffected individuals (should only be done if affected individuals are unavailable, eg. deceased)

• Relative of individual with known BRCA1 or BRCA2 mutation. Note: specific family mutation only tested
• Ashkenazi Jewish and first or second-degree relative of individual with one of the following:
  • Breast cancer under 50 years
  • Ovarian cancer at any age
  • Male breast cancer
  • Breast cancer at any age, with positive family history of breast or ovarian cancer.

Note: testing limited to ethnic specific mutations, unless other criteria given in this list are met.
• A pedigree strongly suggestive of hereditary breast or ovarian cancer, ie. Risk of carrying a mutation for the individual being tested is more than 10%

Multiple cases in the family of the following cancers related to the hereditary non-polyposis colorectal cancer (HNPCC) spectrum, with at least one relative affected with colorectal or endometrial cancer. Age of onset less than 50 years, in closely related relatives and in more than one generation, would raise the index of suspicion.
Note: cancers related to the HNPCC spectrum include: colorectal, endometrial, gastric, small bowel, hepatobiliary, pancreatic, ovarian, kidney, ureter, sebaceous carcinoma of the skin and brain cancers.

• Age at diagnosis of colorectal cancer less than 35 years
• Multiple primary cancers in one family member (see note above for tumour sites)
• Family member with family adenomatous polyposis (FAP), or 10 or more adenomatous polyps (suggestive of attenuated FAP)
• Family member with a colonic adenoma or cancer with high microsatellite instability (MSA)
• Family member with a known mutation causing either HNPCC or FAP

If a tumour sample is unavailable, germline testing may proceed on the youngest living, affected individuals from families meeting the first two criteria’s only.

• Affected and unaffected individuals from families with a known HNPCC causing mutation.
• Affected individuals from Amsterdam I and Ii families. Family must meet all of the following criteria:

a. Three affected relatives with any combination of colorectal, endometrial, small bowel, ureter, transitional cell kidney cancer (urothelial), sebaceous adenoma/carcinoma and or keratoacanthoma. One should be a first degree relative of the other two. At least two successive generations should be affected/ At least one diagnosis must be made before the age of 50. FAP should be excluded. Tumours should be verified by pathological examination.

• Affected individuals from families with: three affected individuals, one with colorectal cancer, and the other two with any combination of colorectal, endometrial, small bowel, ureter, sebaceous adenoma/carcinoma, ovarian, pancreatic, kidney (transitional cell cancer only), gastric, primary brain or primary hepatobiliary cancer. Two of the three family members must be a first degree relationship. At least one diagnosis must be under the age of 50. FAP should be excluded. Tumours should be verified by pathological examination.
• Individuals affected with CRC and a second primary HNPCC-associated cancer (as listed in the above bullet). This includes synchronous and metachronous colorectal cancers. At least one primary cancer must be diagnosed under the age of 55. Families are eligible with or without family history of HNPCC-associated cancer, and tumours should be verified by pathological examination.
• Individuals diagnosed with CRC under the age of 35. Families are eligible with or without family history of HNPCC-associated cancer, and tumours should be verified by pathological examination.
• One case of CRC under 50 years, with a first or second degree relative with one of the following HNPCC-related cancers diagnosed at under 50 years: colorectal, endometrial, small bowel, ureter, urothelial, sebaceous adenoma/carcinoma or keratoacanthoma.
• Individuals with immunodeficient tumours (regardless of family history) as follows: MSH2 deficient tumour +/- MSH6 deficiency (sequence and MLPA of MSH2 gene only). MSH6 (only) deficient tumour (sequence and MLPA of MSH6 gene only). MLH1 deficient tumour in individual less than 60 years (sequence and MLPA of MLH1 gene only).

Testing for familial adenomatous polyposis (FAP):

• Affected and unaffected individuals from families with a known FAP causing mutation
• Individuals with clinical confirmed FAP (100 or more adenomas)
• Individuals with putative attenuated FAP, that is, 10 or more histologically confirmed adenomas. Cumulative pathology and endoscopy reports are required to confirm that the total number and histology are appropriate. A referral with less than 10 adenomas (including hyperplastic polyps) will be excluded. Testing for HNPCC will precede APC testing if individuals meet HNPCC testing criteria.

Medical information about you and your family will be reviewed, using the family history questionnaire you completed ahead of time. We will give you information about your cancer risk and your options for cancer screening.

Your appointment may be a group information session with other individuals who have a family history of cancer. Or your appointment may be a one-on-one session. If you receive an appointment for a group information session, a genetic counsellor will be available to answer questions if needed.

Appointments usually last one tot wo hours, which gives you plently of time to ask the physician or genetic counsellor questions.

Please bring your health card and arrive 20 minutes before your appointment so that registration can be completed first.

Hereditary cancer is typically suspected in families when several members of more than one generation develop cancer, and these cancers are diagnosed at a relatively young age (less than 50). Hereditary cancer is also suspected if a particular type of cancer, or a recognizable pattern of cancers, cluster in a family. About 5-10% of all cancer cases are thought to be due to an inherited gene mutation. Therefore, most cancer is not hereditary.

Hereditary breast and ovarian cancer syndromes are associated with mutations in one of two genes, BRCA1 and BRCA2. Approximately 20-30% of families that are suggestive of a hereditary breast and ovarian cancer syndrome will test positive for a mutation in BRCA1 or BRCA2. However, there may be other genes that predispose to breast cancer.

If your family and/or personal history of cancer suggests that an inherited mutation may be involved, the possibility of genetic testing will be discussed during your genetic counseling appointment. Due to the complexities of genetic testing, it is most useful to begin testing on a family member who has been diagnosed with breast or ovarian cancer. Genetic test results can take many months to obtain.

There are three possible results from initial testing for a BRCA1 or BRCA2 mutation:
Mutation Detected: A gene change (mutation) known to increase cancer risk has been identified. This likely explains the family history of cancer. Genetic testing for this mutation would be available to other family members.

No Mutation Detected: A gene change in BRCA1 or BRCA2 has not been identified. This does not rule out a hereditary cancer predisposition. It is still possible that the individual carries a mutation that the testing cannot detect or a mutation in another, as yet undiscovered, cancer predisposition gene. Screening and management decisions should be based on family history and other personal risk factors.

Uncertain Variant: A gene change that has not been well described. Additional studies would be required to determine whether this gene change is part of normal gene variation or is a mutation which increases cancer risk.

We have two copies of every gene in our body, one from our mother and the other from our father. Having one nonworking copy of a BRCA1 or BRCA2 gene is enough to increase one’s predisposition to cancer. When an individual (male or female) has a BRCA1 or BRCA2 mutation, he/she has a 50% chance of passing it on to each child. This is known as autosomal dominant inheritance.

All women can consider monthly breast self-exams and have clinical breast exams annually by their physician. Annual mammograms beginning at age 40, or 10 years before the earliest diagnosis of breast cancer in the family, are recommended. Women with ≥ 25% lifetime risk for developing breast cancer are also eligible for MRI (where available). Screening recommendations may change over time as our knowledge of breast cancer increases. Personalized screening recommendations will be provided as part of your genetic counselling appointment.

Ovarian cancer screening is not routinely recommended. The available screening methods have not been proven to reliably detect ovarian cancer at an early stage. All women should be aware of the symptoms of ovarian cancer and should approach their doctor promptly if they have any unusual abdominal, gynecological or urinary symptoms.

Women
Breast cancer: BRCA1: 50% to 85%. BRCA2: 50%-85%. General population risk: 11%.
Ovarian cancer: BRCA1: 20-60%. BRCA2: 10% to 30%. General population risk: 1.5%.

Men
Prostate cancer: BRCA1: increased risk. BRCA2: Increased risk. General population risk: 10% to 15%.
Breast cancer: BRCA: Increased risk. BRCA2: 6%. General population risk: 0.1%.

Men and women who carry a BRCA1 or BRCA2 mutation may have a slightly increased risk for other cancers as well, such as melanoma, gallbladder/bile duct, pancreatic, gastrointestinal and hematologic cancers. The exact risk figures have not yet been calculated.

Hereditary cancer is typically suspected in families when several members over multiple generations develop cancer, often at a relatively young age (less than 50). Hereditary cancer is
also suspected if a particular type of cancer, or a recognizable pattern of cancers, cluster in a
family. About 5-10% of all cancer cases are thought to be due to an inherited gene mutation. Therefore, most cancer is not hereditary.

Lynch syndrome (previously known as Hereditary Non-Polyposis Colorectal Cancer - HNPCC)
is the most common hereditary colon cancer syndrome and accounts for approximately 2% to 3% of cases. Lynch syndrome is associated with mutations in 1 of 5 genes; MLH1, MSH2, MSH6, PMS2 and EPCAM. These genes are involved in correcting DNA damage.

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Men and women who carry a Lynch syndrome mutation have a smaller (<10%) increased risk for other cancers such as urinary tract, small bowel, pancreas, hepatobiliary tract brain and specific types of skin cancer.

MLH1 and MSH2 gene changes are the most common cause of LS. Cancer risks differ between mutation types, men and women and within and between families

Due to the complexities of genetic testing, it is most useful to begin testing on a family member who has been diagnosed with colorectal cancer. For the first part of Lynch Syndrome testing, screening tests are performed on a tumor sample.

Mutation Detected: A gene change (mutation) known to increase cancer risk has been identified. This likely explains the family history of cancer. Genetic testing for this mutation would be available to other family members.

No Mutation Detected: A gene change in the specific Lynch Syndrome gene tested has not been identified. This does not rule out a hereditary cancer predisposition. It is still possible that the individual carries a mutation that the testing cannot detect or in another cancer predisposition gene. Screening and management decisions should be based on family history and other personal risk factors.

Uncertain variant: Testing identified a gene change, but the significance of the change has not yet been determined. Additional studies by researchers would be required to determine whether this gene change is part of normal gene variation or is a mutation which increases cancer risk.