IPLab:Lab 7:Fibroadenoma

Clinical Summary

Four months prior to admission, this 25-year-old female became aware of a lump beneath the areola of her right breast. Physical examination confirmed the presence of an approximately 3 cm movable, rubbery mass. An aspiration was attempted but did not yield any fluid or cells. At the time of surgical exploration, a well-circumscribed mass was identified and removed.

Images

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  This low-power photomicrograph of the surgical specimen demonstrates three ovoid, well-circumscribed nodules surrounded by fibroadipose tissue.

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  This is a higher magnification of one of the three nodules. At this power, the nodule seems to be composed of a solid parenchyma with small glandular spaces. The adjacent breast parenchyma consists mostly of fat.

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  This is a higher magnification of the fibroadenoma showing the dense stroma of the tumor surrounding the irregularly shaped ducts. The adjacent fibrofatty tissue containing breast ducts and lobules has been compressed by the tumor.

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  This photomicrograph shows the compressed connective tissue (arrow) between two nodules of dense fibrous tissue and ducts.

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  This is a higher-power photomicrograph of fibroadenoma showing ducts embedded in connective tissue.

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  This is a high magnification of the fibroadenoma showing the dense stroma of the tumor surrounding the irregularly shaped duct. The ducts are lined by two cell layers, one of cuboidal, two columnar cells (inner layer) and an outer layer of flattened cells with hyperchromatic nuclei (myoepithelial cells).

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  This is a higher magnification of fibroadenoma showing irregularly shaped ducts lined by two layers of cells as previously described.

Study Questions

• What tissue makes up the neoplastic portion of the fibroadenoma?

Fibroadenomas are new growths of glandular and stromal tissues. Cytogenetic studies have shown that in some cases only the fibrous (stromal) component is clonal. These tumors appear to arise from the specialized intralobular stroma.

• At what age do fibroadenomas usually occur?

They occur at any age within the reproductive period of life, but they are somewhat more common before age 30.

• Why do fibroadenomas cause problems in pre-menopausal women?

The epithelium of the fibroadenoma is responsive to hormones. Slight increases in size may occur during the late phases of each menstrual cycle, and pregnancy may stimulate growth and lactation. Postmenopausally, regression or calcification may result. There is also a slightly increased risk for development of breast carcinoma.

Additional Resources

Reference

• eMedicine Medical Library: Breast Abscess and Masses
• Merck Manual: Evaluation of Breast Disorders