Breast cancer is the most common cancer worldwide. It is the major cause of cancer-related deaths in most countries including the US. It is estimated that there is one breast cancer case detected every 14 seconds in the world. Early detection remains the primary way to prevent the development and spread of breast cancer. A cancer screening program, therefore, must carefully consider all the risks of developing breast cancer, the benefits, and harmful effects of the screening intervention, along with the cost involved. 

Time and again, National Comprehensive Cancer Network® (NCCN®) guidelines have helped healthcare providers and oncologists with strategies and treatment plans for cancer. With so many conflicting recommendations floating around for breast cancer screening, the new NCCN updated guidelines will help patients in getting a clear understanding of the disease condition, its screening procedures, and treatment suggestions.

According to these guidelines, breast cancer risk assessment is recommended for all women from 25 years of age with emphasis on annual mammography screening from the age of 40 years for those with average risk because it is a screening approach that has proven to offer the greatest mortality reduction. Women with increased risk include those with family history, and those exposed to thoracic radiation therapy (RT) between ages 10 and 30 years (5-year risk of invasive breast cancer ≥1.7% in individuals ≥35 y, atypical ductal hyperplasia, lobular neoplasia). These women must be referred to a genetic or other health professional with expertise and experience in cancer genetics (1).

Screening is also important for those who are pregnant or breastfeeding; the risk of ionizing radiation exposure with mammography is manyfold but still below the threshold of fetal teratogenesis. An earlier start is recommended for those who have additional risk factors (2). For palpable breast symptoms during pregnancy, an ultrasound is recommended. There may be a small theoretical concern regarding milk fistula biopsy, in such cases, an image-guided core needle biopsy is recommended following a BI-RADS 4 or BIRADS 5 imaging result during pregnancy. However, an MRI is not recommended during pregnancy. Pregnancy should not alter the management of follow-up in case of a BI-RADS 3 finding. It is recommended breastfeeding mothers should either pump or breastfeed just before imaging to improve sensitivity and comfort of the examination. Axillary mass development during lactation is not uncommon which could be due to normal lactational changes in accessory axillary breast tissue that are present in ~15% of individuals. However, if after clinical examination there remain concerns that the physical findings are not normal in the axillary breast tissue then the healthcare providers should proceed with the evaluations as already recommended.

The updated guidelines also address breast symptoms, such as a palpable lump, pain, or nipple discharge, and emphasize the need for prompt clinical and diagnostic evaluation. Women with persistent nipple discharge beyond 1 or 2 episodes should undergo evaluation. It is recommended that in case of persistent bloody nipple discharge without abnormal breast imaging, a breast surgical expert should be consulted to evaluate possible further course of action (e.g., duct excision). Contrast-enhanced mammography or whole breast ultrasound is recommended for those who qualify for MRI but cannot undergo it. 

In patients undergoing RT, an annual screening mammogram tomosynthesis is recommended. Evidence indicates tomosynthesis can decrease call-back rates and improve cancer detection compared with 2D mammography alone. Radiation exposure may be increased, as per FDA guidelines. Current evidence is not in support of the routine use of thermography as a screening procedure. 

The guidelines further emphasize that individuals with breast erythema or suspicious skin changes should be directed to undergo age-appropriate breast imaging evaluation. In case of clinically low suspicion for Paget's disease or high suspicion for eczema, a short trial of topical steroids is recommended. When imaging indicates possible abscess as the cause of focal pain, aspiration or surgical consultation is recommended. 

There is a lack of evidence and not enough clinical trials to enable the application of this screening guidance for transgender individuals. Transgender individuals should, therefore, consult with their primary care physician to determine an appropriate screening procedure.

References:

1. Updated Breast Cancer Screening Guidelines for Women Over 40 [Internet]. Cancer Health. 22AD. Available from: https://www.cancerhealth.com/article/updated-breast-cancer-screening-guidelines-women-40

2. New NCCN Guidelines for Mammography: All Women Over 40 [Internet]. MedScape. 22AD. Available from: https://www.medscape.com/viewarticle/978273#vp_2