Benign breast conditions: Pathology review

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Case Study0:00–1:21

A 40-year-old musician named Anne-Marie comes to the primary care clinic. She mentions that multiple lumps in her breast would come and go at different times during her menstrual cycles.
For the past year, she has also experienced premenstrual breast pain in both breasts. On physical exam, multiple lumps were found on the upper, outer quadrant of the right breast.
At the same time, Ashley, who is a 32-year-old Rehabilitation Technician, comes to the clinic because of a breast lump that she noticed 8 weeks ago.
She reports that a lump seems to become more tender and increase in size during her period. Physical examination shows a palpable, mobile, firm mass in the right upper outer quadrant of the right breast.
At first glance, you’d think Anne-Marie and Ashley both have similar problems, but the fact is, they have different forms of benign breast conditions.
Now these include fibrocystic breast changes; benign tumors, such as fibroadenoma, intraductal papilloma, and phyllodes tumor; inflammatory processes, such as fat necrosis and lactational mastitis; and gynecomastia.
On your exams, it’s important to differentiate these from possible malignancy based on presentation, history, and other findings.First, let’s start with fibrocystic breast changes, which are the most common benign lesions of the breast that are typically found in premenopausal women between 20 to 50 years of age.

Fibrocystic change1:21–3:12

These individuals usually complain about premenstrual breast pain, which is a very high yield fact and the hallmark symptom of this condition; and multiple lumps, which are typically located in the upper lateral quadrant of the breast.
But often, these lesions can be bilateral and multifocal. Another high yield fact is that the breast pain and lumps are associated with the phases of the menstrual cycle and cyclic ovarian hormonal stimulation.
Fibrocystic breast changes can include simple cysts, which are dilated and fluid-filled ducts; papillary apocrine change or metaplasia; and stromal fibrosis.
Now cysts in fibrocystic breast changes can be clear or blue-domed, due to a light yellow fluid that gives the cyst a blue color when seen through the surrounding tissue.
Remember that fibrocystic breast changes are generally not associated with an increased risk of breast cancer, but there are two subtypes of this condition that are linked with a slightly increased risk for cancer.
The first one is sclerosing adenosis, which is the subtype characterized by calcifications and proliferation of small ductules and acini in the lobules.
The second one is epithelial hyperplasia of cells in terminal ducts and lobular epithelium, which is associated with an increased risk of breast cancer only if there’s a presence of atypical cells.
Either way, you should always order mammography to rule out malignant disease in these individuals. Finally, the mainstay of the management of fibrocystic breast changes is conservative treatment, while iodine supplementation is thought to be of benefit in some individuals with this condition.Now let’s focus on benign breast tumors!

Benign Breast Tumor3:12–7:56

First, there are fibroadenomas, which are the most common breast tumors. They arise from the periductal stromal tissue and are typically seen in premenopausal women, under 35 years of age.
Fibroadenomas are usually asymptomatic and they are discovered on screening exams. On your exam, you should suspect fibroadenoma in a young woman with a small, well-defined, spherical, painless, mobile breast mass.
Moreover, it’s so mobile that is often referred to as the breast “mouse”. On the other hand, in older women, the tumor is usually identified as a mammographic density with possible calcifications.
Generally, these tumors are solitary lesions, but some individuals can present with multiple fibroadenomas, which can occur in both breasts.
Histologically, fibroadenoma of the breast is characterized by an overgrowth of cellular, and often myxoid stroma that surrounds and occasionally compresses epithelium-lined glandular and cystic spaces.
As women age, stroma becomes more hyalinized, while the glandular epithelium atrophies. These tumors can range in size from 1 to more than 10 centimeters.
A high yield fact to remember is that due to their estrogen sensitivity, they can increase in size and tenderness during the luteal phase of the menstrual cycle and lactation.
Individuals with fibroadenoma are usually not at risk for developing breast cancer, but they should undergo mammography and ultrasound to exclude malignancy.
Therapy is often unnecessary because these tumors typically regress with menopause; so the mainstay of the management is observation and reassurance.
On the other hand, some individuals can undergo cryoablation, which is a noninvasive method of treatment that utilizes low temperature to decrease the size of the tumor.Next, we have intraductal papilloma, which is a small benign fibroepithelial papillary tumor within the lactiferous ducts of the breast.
This tumor is most commonly found just beneath the areola, but according to its site of origin, it can be classified into central intraductal papilloma, which typically presents as a single lesion; and peripheral intraductal papilloma, which usually presents as multiple lesions.
Typically these lesions are small and can not be seen on the skin or palpated. However, you have to remember that intraductal papilloma is the most common cause of serous or bloody discharge from the female breast.
This discharge is usually unilateral and not associated with breast masses or regional lymphadenopathy. Another high-yield fact to know is that young, premenopausal women, under 35 years of age, are at increased risk of developing intraductal papilloma.
Unlike the previous conditions, intraductal papillomas is associated with a slightly increased risk of developing breast cancer.
So remember, in a woman with bloody nipple discharge you need to perform a biopsy to rule out papillary carcinoma, which is an important differential diagnosis of intraductal papilloma.
As far as diagnosis goes, mammography is not used for visualizing the site of intraductal papilloma since it’s too small to be detected.
Instead, the most specific imaging modality for the diagnosis is galactogram, which is a diagnostic procedure used to visualize the breast ducts.
Finally, microdochectomy is the procedure performed for the management of intraductal papilloma and excision of the lactiferous duct.Moving on to phyllodes tumor!
The name of this tumor comes from the Greek word phullon, which means leaf. Histologically, it’s characterized by a large mass of connective tissue and cysts with “leaf-like” projections.
It typically arises from the periductal stromal cells. This tumor typically presents as a painless mass in the breast and it’s most commonly seen in postmenopausal women.
Moreover, the breast mass associated with phyllodes tumor can resemble a fibroadenoma but has a faster growth rate, often showing noticeable growth from week to week.
For your exam, you have to know that phyllodes tumor can become malignant! They appear as well circumscribed lesions on mammogram but the diagnostic tool of choice is a core needle biopsy; axillary lymph node dissection is not indicated for individuals with this tumor.
Finally, the best initial management of phyllodes tumor is surgical excision.Now, switching gears and moving on to inflammatory processes!

Inflammatory Condition7:56–11:28

First let’s start with fat necrosis of the breast, which is a benign non-suppurative inflammatory lesion that occurs when an area of fatty tissue gets damaged.
It’s important to note that up to 50% of individuals with fat necrosis of the breast, don’t report breast trauma, but on your exams, this could be the best clue.
On physical exam, you will detect a breast lesion that presents as a painless fixed mass with possible skin or nipple retraction.
Fat necrosis of the breast is diagnosed by mammography, which shows calcified oil cysts; and biopsy, which shows partially necrotic adipose tissue with foamy macrophages and multinucleated giant cells.
The next one is mastitis, which is an inflammation of the breast parenchyma. This usually leads to swollen, red and painful areas on the breast, and sometimes fever.
Lactational mastitis occurs during breastfeeding and it’s most commonly caused by Staphylococcus aureus entering through cracks in the nipple.
For your exam, it’s crucial to remember that breastfeeding should continue during an episode of mastitis. Next, there’s periductal mastitis, a type of mastitis that involves vitamin A deficiency that results in squamous cell metaplasia of the lactiferous ducts, causing blockage of the duct and subsequent inflammation.
This type of mastitis is commonly seen in smokers. Finally, mammary duct ectasia is a rare cause of mastitis where inflammation and fibrosis cause blockages in subareolar ducts, causing them to dilate.
This blockage causes fluid build up in the duct which can lead to bacterial mastitis. Individuals with mammary duct ectasia present with a periareolar mass and a green-brown nipple discharge that is a result of inflammatory debris and bacteria.
Since S. aureus is the most common pathogen causing lactational mastitis, antibiotics such as amoxicillin/clavulanate, cephalexin, ciprofloxacin, clindamycin, and trimethoprim/sulfamethoxazole are often used to treat these individuals.
The last condition is gynecomastia, which is benign breast enlargement in males due to increased estrogen activity and decreased androgen activity.
This enlargement is caused by proliferation of glandular tissue and it can be unilateral, bilateral, or present as a mass around the nipple area.
Based on the cause, gynecomastia can be classified into idiopathic gynecomastia, where the cause is unknown; physiologic gynecomastia, which is commonly seen in newborn males due to the mother’s estrogen, or the elderly males due to decreased androgen production, but it can be also seen during puberty.
Pathological gynecomastia can be seen in cirrhosis where there’s increased conversion of androstenedione to estrogen, and testicular germ cell tumors can secrete hCG that also has a similar effect.
Next hypogonadism, like in people with Klinefelter syndrome, can decrease androgen production. Also, pathological gynecomastia can be caused by medications such as spironolactone which converts testosterone to estrogen.
Next, hormone therapy for prostate cancer uses antiandrogen agents like bicalutamide which can also cause gynecomastia. All right, as a quick recap.
Fibrocystic breast changes arise from within the glands and are the most common benign lesions of the breast, which are typically found in premenopausal women, 20 - 50 years of age.

Review11:28–13:01

Key findings include premenstrual breast pain and single or multiple lumps, which are typically located in the upper lateral quadrant of the breast.
Fibroadenoma is the most common breast tumor, which is most commonly seen in premenopausal women, under 35 years of age.
This tumor presents as a small, well-defined, spherical, painless breast mass that’s highly mobile in younger individuals.
Intraductal papilloma is a small benign fibroepithelial papillary tumor within the lactiferous ducts of the breast, usually found just beneath the areola; while phyllodes tumor is histologically characterized by a large mass of connective tissue and cysts with “leaf-like” projections.
Next, inflammatory processes of the breast include fat necrosis, which is a benign non-suppurative inflammatory lesion that occurs when an area of fatty breast tissue gets damaged; and mastitis, which refers to an inflammation of the breast parenchyma.
Moreover, lactational mastitis occurs during breastfeeding and it’s most commonly caused by Staphylococcus aureus entering through cracks in the nipple.
Finally, gynecomastia is benign breast enlargement in males due to increased estrogen activity and decreased testosterone activity.
Now let’s go back to our case! Anne-Marie noticed multiple lumps in her breast that would come and go at different times during her menstrual cycles.

Summary13:01–13:52

Also, she complained about premenstrual breast pain, therefore we should assume that Anne-Marie has fibrocystic breast changes.
On the other hand, Ashley noticed a breast lump that becomes more tender and increases in size during her period. In other words, she has an estrogen-sensitive breast condition!
In combination with a physical examination, which showed a palpable, mobile, firm mass in the right upper outer quadrant of the right breast, we can assume Ashley has fibroadenoma.
Finally, we should explain to Anne-Marie and Ashley, that their conditions are not associated with an increased risk of breast cancer, but either way, we should order mammography to rule out any breast malignancies.
Benign breast conditions: Video, Causes, Symptoms | Osmosis