GENETICS OF BREAST CANCER Genetic relationships to cancer BRCA1 and BRCA2 Tumor suppressor genes Involved in repairing damaged DNA and maintaining genomic instability. BRCA1 also increase the risk of ovarian cancers, pancreatic, prostate and melanoma. Women with BRCA1 have a higher lifetime risk. BRCA2 are also linked to ovarian cancer. Peutz-Jegherns syndrome: Autosomal dominant Hamartomata’s polyposis syndrome characterised by the presence of less than 20 polyps. Associated with a mutation in the STK11 gene. Mucocutaneous pigmentation Dark spots on the lips, oral mucosa and skin. Manifests with: Hematochezia Constipation Diarrhea Mucocutaneous hyperpigmentation Increased risk of: Colorectal cancer Ovarian cancer Breast cancer Pancreatic cancer Screening for breast cancers Women over 40 every 2 years. May be recommended for this woman, if they have a moderate risk. Women aged 50 to 74 are actively invited to screen. Advantages Finds cancers early Screening prevents death Disadvantages A small number of cancers are missed Some women will be offered unnecessary treatment Small exposure to radiation Early breast cancer The cancer has not spread beyond the breast or the axillary lymph nodes one same side. Usually, stage 1 or 2. Stage 1 -> earliest stage of invasive breast cancer. Cancer has spread from its original location, but still in a small area. Tumor is less than 2 cm. No cancer cells in the lymph nodes. Stage 2 Larger than stage 1 May have spread to a few nearby lymph nodes. Can be categorised into 2A or 2B: 2A -> only one of the following applies: Less than 2cm and spreads to 1 to 3 lymph nodes in the axilla. Tumor is between 2 to 5 cm in size but have not yet spread to lymph nodes. No tumor has found in the breast, but breast cancer cells have been found in 1 to 3 lymph nodes in the axilla. 2B -> on of the following applies: Tumor is 2 to 5cm in size and cancer cells have spread to 1 to 3 lymph nodes. Tumor is larger than 5cm but no spread to lymph nodes.