Breast cancer

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Breast cancer

Reproductive system


Breast cancer


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USMLE® Step 1 questions

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High Yield Notes

12 pages


Breast cancer

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USMLE® Step 1 style questions USMLE

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A 50-year-old woman comes for a follow-up meeting after she was diagnosed with invasive ductal carcinoma breast cancer. A 2-cm spiculated lesion was seen on mammography and confirmed with biopsy. She would like to know what the prognosis is for her condition. Which of the following findings is the worse prognostic factor for her conditions?  

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Aromatase inhibitors p. 680

breast cancer p. 727

Axillary lymph nodes

breast cancer and p. 674

BRCA1/BRCA2 genes p. 222

breast cancer and p. 674

Breast cancer

hypercalcemia and p. 221

incidence/mortality of p. 202

key associations p. 731

oncogenes and p. 222

paclitaxel for p. 449

paraneoplastic cerebellar degeneration and p. 221

postmenopausal women p. 727

tamoxifen for p. 450

trastuzumab for p. 450

tumor suppressor genes and p. 222

Breast tumors (malignant) p. 674-675

aromatase inhibitors for p. 680

breastfeeding and p. 652

hormonal contraception contraindication p. 681

Estrogen p. 654, 680

benign breast tumors p. 673

breast cancer p. 674

Inflammatory breast carcinoma p. 674

Lymph drainage

malignant breast tumors p. 674


breast cancer risks p. 674

Tamoxifen p. 450, 680

for breast cancer p. 727


Breast cancer, or breast carcinoma, is an uncontrolled growth of epithelial cells within the breast. It’s the second most common cancer in women, but can also, on rare occasion, affect men as well.

Breast cancer is also the second leading cause of cancer deaths in women after lung cancer. This is largely due to the fact that oftentimes breast cancers don’t cause any pain or discomfort until they’ve spread to nearby tissues.

The breasts are milk-producing glands that sit on the chest wall, on either side of the breast-bone. They lie on top of the ribs and the pectoral muscles, and they’re divided into three main parts.

The glandular tissue that makes the milk, is made up of 15 to 20 lobules. Inside each of these lie a bunch of grape-like structures called the alveoli, which are modified sweat glands surrounded by a basement membrane made largely of collagen.

Zooming in on the alveoli, there’s a layer of alveolar cells that secrete breast milk into the lumen which is the space in the center of the gland.

Wrapping around the alveolus are special myoepithelial cells that squeeze down and push the milk out of the lumen of the alveolus, down the lactiferous ducts, and out one of the pores on the nipple.

Now, surrounding the glandular tissue is the stroma, which contains adipose or fat tissue, and this makes up the majority of the breast.

Suspensory ligaments called Cooperʼs ligaments, run through the stroma and help keep it in place. These ligaments attach to the inner surface of the breast skin on one end and the pectoralis muscles on the other.

Just below the skin over the breast, there’s a network of tiny lymphatic vessels that drain the lymph, which is a fluid containing cellular waste products and white blood cells. These lymphatic vessels mainly drain into a group of lymph nodes in the axilla, or the armpit.


  1. "Robbins Basic Pathology" Elsevier (2017)
  2. "Harrison's Principles of Internal Medicine, Twentieth Edition (Vol.1 & Vol.2)" McGraw-Hill Education / Medical (2018)
  3. "Pathophysiology of Disease: An Introduction to Clinical Medicine 8E" McGraw-Hill Education / Medical (2018)
  4. "CURRENT Medical Diagnosis and Treatment 2020" McGraw-Hill Education / Medical (2019)
  5. "Mammographic Density and the Risk and Detection of Breast Cancer" New England Journal of Medicine (2007)
  6. "Effect of physical inactivity on major non-communicable diseases worldwide: an analysis of burden of disease and life expectancy" The Lancet (2012)

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