Go to the website http://www.cancer.gov and select 'Cancer Types'...

Question

Go to the website http://www.cancer.gov and select 'Cancer Types' on the top menu bar. Scroll down to 'Breast Cancer' and click. Select 'Cases & Prevention' from the options. Click 'More information' and select 'BRCA Mutations: Cancer Risk and Genetic Testing'. Use the information on this page to answer the following questions.

What are the approximate percentage increases in risk of having breast cancer and of having ovarian cancer for women inheriting harmful mutations of BRCA1 and BRCA2 compared with the risks in the general population?

Accepted Answer

Hi, everybody. Here's our next question. It says, and we have two statements here. Statement A by age 70 approximately 50 out of 100 women with a BRC A one or BRC A two mutation will develop breast cancer. Statement B, ovarian cancer affects about 70 out of 100 women who carry the BRC A one or BRC A two mutation by the age of 70. Which of the following is accurate. Choice. A both statements are correct. B both statements are incorrect. C only statement A is correct or B only statement B is correct. So let's look at our statements and see which one is true or ones are true. Statement A says that by age 70 approximately 50 out of 100 women with those BRCA mutations will develop breast cancer. That is true. So, statement A is correct. So that could mean that C is correct or that A is our answer. Both statements are correct. So we'll go ahead and eliminate choice B both are correct in both are incorrect. Excuse me and choice D only statement B is correct. So let's look at statement B which says ovarian cancer affects about 70 out of 100 women who carry those mutations by the age of 70. Well, this is too high. Uh When you look at women with this mutation for the BRC A one mutation, uh approximately 10 to 27% of women with that mutation go on to develop ovarian cancer. And in the case of the BRC A two mutation, 6 to 12% of them go on to develop ovarian cancer by age 70. So that's 30% or less, much lower than the 70 out of 100 that statement B states. So statement B is definitely incorrect. So we can eliminate choice. A, both statements are correct and our answer choice must be choice. C only statement A is correct. In this case, see you in the next video.

Key Concepts

BRCA1 and BRCA2 Genes

Cancer Risk Assessment

Genetic Testing

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