Benign Breast Diseases (Mastitis, Fibrocystic changes, etc.)
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Benign Breast Diseases
The female and male breasts are anatomically similar, though adult female breasts have more adipose tissue and a more developed ductal system; this is particularly true in those who are pregnant or lactating.
The physiological role of the breast is to produce and transport milk during the hormonally regulated process of lactation (for more on hormonal regulation, click here: prolactin).
"Benign breast disease" is an umbrella term for non-malignant lesions; it is more common in premenopausal women, whereas malignant lesions are more common in postmenopausal women.
Lesions may be discovered via imaging, or patients may present with pain, masses, or nipple discharge.
Symptoms may be cyclical, due to changes in estrogen levels during the menstrual cycle.
To diagnose non-malignant lesions and rule out the possibility of breast cancer, we can use imaging (such as mammograms and MRI), biopsy, and conduct nipple discharge analyses.
Breast anatomy & lesion locations
First, we show the outline of the breast, which is covered in skin.
The majority of the breast tissue comprises adipose and connective tissues.
The ductal system:
- Lobular stroma surrounds the lobules, which are the glands that produce milk.
- Lobuless drain to terminal ducts, which drain to the main ducts that carry milk to the nipple.
- The lactiferous sinus is in the nipple; the sinus is a dilation of the duct. We also show some smooth muscle tissue to the sides of the nipple.
Pathologies by location:
- In the lobular stroma we find fibroadenomas and phyllodes tumors.
- In the lobules and terminal ducts, we find fibrocystic changes and carcinomas.
- In the lactiferous sinus and main ducts, we find mastitis, intraductal papilloma, and Paget disease of the breast.
- In the Interlobular stroma and fat, we find fat necrosis.
Benign Breast Diseases
Fibrocystic changes:
Fibrocystic changes are the most common benign breast condition; about half of premenopausal women over age 30 have some degree of fibrocystic change in their breast tissues.
Fibrocystic changes are classified as nonproliferative and proliferative:
Nonnproliferative changes include simple fluid-filled cysts in the terminal ducts and papillary apocrine metaplasia with stromal fibrosis. Dark spots of calcifications often appear in fibrocystic changes.
Proliferative changes, are associated with an increased risk of breast cancer, can present with or without atypia:
Sclerosing adenosis represents proliferative changes without atypia – we show an enlarged terminal lobule duct unit with proliferation of the glandular tissue.
Proliferative changes with atypia are represented by epithelial hyperplasia, in which overgrowth of epithelial cells crowds the lumen of the duct.
In general, fibrocystic changes do not require treatment; if painful, cysts can be drained and over-the-counter pain relievers are recommended.
Inflammatory processes of the breast
Fat necrosis occurs in response to trauma or breast surgery; we see necrotic fat tissue, often with giant cells (multinucleated macrophages formed by the union of several cells). Fat necrosis often resolves on its own, and does not require surgical intervention unless its persistence causes pain.
Mastitis occurs when the milk ducts become blocked and/or when there is bacterial infection in the ducts (usually associated with S. aureus). Patients often present with swollen, painful breasts with erythema; infection can also cause flu-like symptoms with fever.
Mastitis most often occurs during breastfeeding, when the skin of the nipple becomes dry and cracked, allowing easy pathogen entry.
We can treat infections with antibiotics.
Benign Breast Tumors:
Fibroadenomas are common, particularly in women younger than 35 years old. Masses are usually small with a round or oval shape and well-defined borders; they can be soft or firm.
Fibroadenomas are often larger when estrogen levels are higher, so they grow during pregnancy and shrink after menopause.
Phyllodes tumors are rare, and most often diagnosed in women in their 40s or 50s. These fibro-epithelial tumors have a leaf-like lobulation pattern with stromal proliferation ("phyllode"s refers to their leaf-like appearance).
These tumors can be malignant, and can rapidly grow to large sizes (over 10 cm), which stretches the skin of the breast.
Tumors can be surgically removed, and, if borderline or malignant, radiation therapy may be recommended.
Intraductal papilloma is a cancer precursor lesion that grows in the lactiferous ducts, often under the areola; intraductal papilloma a common cause of serous or bloody nipple discharge.
These small fibroepithelial tumors have a characteristic "wart-like" appearance in histological samples of affected ducts.
Gynecomastia
Enlarged breasts in males; this is physiologic in prepubertal and older males (when estrogen to testosterone ratios are naturally higher).
However, in post-pubertal males, gynecomastia may be a sign of cirrhosis, hypogonadism, testicular tumors; gynecomastia can also be caused by some medications (for example, spironolactone).
References
- "Breast Fibroadenoma - StatPearls - NCBI Bookshelf." Accessed November 17, 2022. https://www.ncbi.nlm.nih.gov/books/NBK535345/.
- Chen, Shu-Tian, Satoko Okamoto, Bruce L Daniel, James Covelli, Wendy B DeMartini, and Debra M Ikeda. "Pure Fibrocystic Change Diagnosed at MRI-Guided Vacuum-Assisted Breast Biopsy: Imaging Features and Follow-up Outcomes." Journal of Breast Imaging 2, no. 2 (March 25, 2020): 141–46. https://doi.org/10.1093/jbi/wbz090.
- Genova, Rafaella, and Robert F. Garza. "Breast Fat Necrosis." In StatPearls. Treasure Island (FL): StatPearls Publishing, 2022. http://www.ncbi.nlm.nih.gov/books/NBK542191/.
- Li, Allen, and Lindsey Kirk. "Intraductal Papilloma." In StatPearls. Treasure Island (FL): StatPearls Publishing, 2022. http://www.ncbi.nlm.nih.gov/books/NBK519539/.
- Malherbe, Kathryn, Myra Khan, and Saira Fatima. "Fibrocystic Breast Disease." In StatPearls. Treasure Island (FL): StatPearls Publishing, 2022. http://www.ncbi.nlm.nih.gov/books/NBK551609/.
- Nephron. English: Very High Magnification Micrograph of Fibrocystic Change of the Breast, Also Fibrocystic Breast Changes and Fibrocystic Disease, with Apocrine Metaplasia. H&E Stain. Own work. Accessed November 22, 2022. https://commons.wikimedia.org/wiki/File:Fibrocystic_change_-_very_high_mag.jpg.
- "Nonproliferative Fibrocystic Changes." Accessed November 22, 2022. https://www.pathologyoutlines.com/topic/breastfcc.html.
- "Phyllodes Tumor." Accessed November 22, 2022. https://www.pathologyoutlines.com/topic/breastphyllodesgeneral.html.
- "Phyllodes Tumors of the Breast | American Cancer Society." Accessed November 17, 2022. https://www.cancer.org/cancer/breast-cancer/non-cancerous-breast-conditions/phyllodes-tumors-of-the-breast.html.
Ramji, Ashwath Narayan. "Fibrocystic Disease of the Male Breast: A Case Report and Literature Review of the Rare Entity," n.d., 2.
- "Sclerosing Adenosis." Accessed November 22, 2022. https://www.pathologyoutlines.com/topic/breastsclerosingadenosis.html.
- Stachs, Angrit, Johannes Stubert, Toralf Reimer, and Steffi Hartmann. "Benign Breast Disease in Women." Deutsches Ärzteblatt International 116, no. 33–34 (August 2019): 565–74. https://doi.org/10.3238/arztebl.2019.0565.
Images:
- Fibrocystic breast: https://commons.wikimedia.org/wiki/File:Fibrocystic_change_-_intermed_mag.jpg
- Fibrocystic breast with epithelial hyperplasia: https://commons.wikimedia.org/wiki/File:Proliferative_fibrocystic_changes_--_intermed_mag.jpg
- Mastitis: https://wikem.org/wiki/File:Mastitis_in_breast.jpg
- Phyllodes tumor: https://en.wikipedia.org/wiki/Phyllodes_tumor#/media/File:Phyllodes_tumour_-_very_low_mag.jpg
- Intraductal papilloma: https://commons.wikimedia.org/wiki/File:Breast_IntraductalPapilloma_LP_PA.JPG
- Gynecomastia: https://commons.wikimedia.org/wiki/File:Breast_IntraductalPapilloma_LP_PA.JPG