Anatomy clinical correlates: Breast

The breasts, formally known as the mammary glands, are situated in the subcutaneous tissue overlying our pectoralis muscles.

There are many conditions that can affect the breast, the most well known being breast cancer. Breast cancer, as well as other conditions that can affect the breast, can often go unnoticed, which has serious clinical consequences; so It is important to understand and recognize these conditions as early as possible.So let’s start with breast cancer, which causes changes to the structure and appearance of the breasts.

One of the classic changes is the presentation of a palpable breast mass, which is typically a hard, immobile lesion with irregular borders most commonly found in the upper outer quadrants.Another indication of more advanced disease are skin changes, specifically the orange-peel appearance, also called the peau d’orange sign, which happens when there’s prominent edema and dimpling of the overlying skin.

Larger dimpling of the skin can result from cancerous invasion of the glandular tissue and fibrosis, which may also pull on the suspensory ligaments of the breast and can cause retraction of the nipple.If the cancer interferes with the lymphatic drainage this can lead to lymphedema, which is when there’s excess fluid in the subcutaneous tissue.

This in turn results in deviation of the nipple and the skin appears thickened and leather-like. Cancer cells can spread through contiguity, which is when the adjacent tissue is invaded.When breast cancer cells invade the retromammary space or the pectoral fascia, or when they metastasize to the interpectoral nodes, the breast elevates when the muscle contracts, and this usually signals advanced cancer.

Furthermore, the local cancerous invasion to the pectoral fascia and pectoralis major muscle below may result in deep fixation of the breast tissue.Breast cancer usually spreads through lymphatic vessels, which basically carry cancer cells from the breast to the lymph nodes, especially those in the axilla.

Communications among lymphatic pathways and among axillary, cervical and parasternal nodes can cause metastases from the breast to develop in the supraclavicular lymph nodes, in the opposite breast or in the abdomen, but the most common site of metastasis of breast cancer remains the axillary lymph nodes.Cancer cells can also spread from the breast through venous routes.

For example, the posterior intercostal veins drain into the azygos system of veins alongside the bodies of the vertebrae.

As a consequence, cancer cells can spread to the vertebrae and from there to the cranium and brain.Breast cancer mainly affects biological females, and it is the most commonly diagnosed malignancy in women in the United states.

However, up to 1.5% of cases occur in biological males.In males, the cancer also usually metastasizes to the axillary lymph nodes in addition to bone, pleura, lung, liver and skin.

In male individuals, a visible or palpable subareolar mass or secretion from a nipple can suggest breast cancer.In males, breast cancer tends to infiltrate the pectoral fascia, pectoralis major muscle and apical lymph nodes in the axilla.

Unfortunately, it frequently goes undetected until there are already metastases.A less worrisome breast clinical condition is polymastia or supernumerary breasts.

They are smaller than the usual breasts and consist of only a rudimentary nipple and areola, which can be mistaken for a mole until they change their color during pregnancy.

They might even have glandular tissue that can develop during lactation.Supernumerary breasts can appear anywhere along a line that extends from the axilla to the groin.

That’s because this is the location of the embryonic mammary crest from which the breasts develop and along which breasts develop in animals with multiple breasts, such as female dogs.Now, amastia is when there’s no breast development or when nipples and areolas are present, but there’s no glandular tissue.

And finally, polythelia is when accessory nipples are present, just like Chandler Bing’s third nipple.Last subject on the breasts is gynecomastia, which is a benign proliferation of the breast tissue in biological males, and it is typically caused by an imbalance between estrogenic and androgenic hormones.

It is age dependent, and it most frequently affects males going through puberty, in which case it resolves spontaneously.Less frequently, it affects older males and it can be caused by liver cirrhosis or testicular cancer, medications like spironolactone, cimetidine, and ketoconazole, among others, and other conditions such as Klinefelter syndrome.Okay, as a quick recap… Breast cancer can change the appearance of the breast.

Signs include a palpable, irregular mass, peau d’orange, retraction of the nipple, lymphedema, and a leather-like appearance.

It mainly affects females, though up to 1.5% of cases occur in males.Polymastia is a condition where an individual has an additional smaller than usual breasts consisting of only a rudimentary nipple and areola, amastia is when there is no breast development, and polythelia is an accessory nipple.

Finally, gynecomastia is when breast tissue becomes visibly enlarged in males, and it can happen because of drugs like spironolactone, or conditions such as liver cirrhosis or testicular cancer.