Practice question answers Pathology of breast III
Practice question answers
Pathology of breast III
© Jun Wang, MD, PhD
1. B. This lesion is characterized by stretched/compressed ducts in a background of markedly proliferated hypocellular fibrous tissue. These features are consistent with fibroadenoma. Diabetic mastopathy is commonly seen in patient with type I diabetes and is characterized by dense lymphocytic infiltration surrounding normal appearing ducts. Fibrocystic changes is a group of pathological processes including stromal fibrosis and cyst formation. Usual ductal hyperplasia has increased layers of benign ductal epithelial cells. Invasive ductal carcinoma has ducts with irregular shape and irregular arrangement, suggestive of stromal invasion. Invasive lobular carcinoma has atypical epithelial cells forming single files in stroma.
2. D. Benign ducts/lobules and non-invasive proliferations have intact myoepithelial layer located between luminal cells and basement membrane. Markers for myoepithelial cells including p63, CK5/6 and CD10 can highlight intact myoepithelial cells at the periphery of these benign ducts/lobules and non-invasive proliferations. Her2 overexpression can be seen in invasive ductal carcinoma and ductal carcinoma in situ. Loss of E-cadherin is seen in lobular carcinoma in situ and invasive lobular carcinoma. Expression of p53 is commonly seen in high grade cancers, including medullary carcinoma and ductal carcinoma and high grade ductal carcinoma in situ. Polyclonal B cells can be seen in non-specific chronic inflammation and diabetic mastopathy.
3. C. This case is characterized by stromal fibrosis and cyst formation. Apocrine metaplasia can be seen. These features are consistent with fibrocystic changes. Atypical ductal hyperplasia is usually less than 3 mm, and has cytological features of low grade, but not high grade ductal carcinoma in situ. Ductal carcinoma in situ has dilated ducts and atypical cells, and forming various patterns including solid, cribriform, papillary and micropapillary appearance. Invasive ductal carcinoma has ducts with irregular shape and irregular arrangement, suggestive of stromal invasion. Mucinous carcinoma is characterized by clusters of atypical cells floating in mucin pool.
4. B. Fibrocystic changes is a group of pathological processes including stromal fibrosis and cyst formation, usually associated with estrogen effects. BRCA1 mutation is seen in basal like carcinoma, including medullary carcinoma. Her2 amplification/overexpression can be seen in invasive ductal carcinoma and ductal carcinoma in situ. Loss of E-cadherin is seen in lobular carcinoma in situ and invasive lobular carcinoma. Trauma is commonly associated with fat necrosis.
5. E. This case is characterized by marked proliferation of hypercellular stroma, forming leag-like appearance. These features are consistent with phyllodes tumor. Fibroadenoma has hypocellular fibrous background. Ductal carcinoma in situ has dilated ducts and atypical cells, and forming various patterns including solid, cribriform, papillary and micropapillary appearance. Invasive ductal carcinoma has ducts with irregular shape and irregular arrangement, suggestive of stromal invasion. Intraductal papilloma usually located at retreareolar area, and has papillary growth with fibrovascular core covered by benign ductal cells.
6. C. This case is characterized by a prominent finger like growth without cytological atypia. Myoepithelial cells are intact by CD10 stain. These features are consistent with intraductal papilloma. Lobular carcinoma in situ is characterized by dilated terminal ducts filled with E-cadherin negative, loosely cohesive cells. Also see discussion of question 1.
7. A. The most commonly seen clinical presentation of intraductal papilloma is bloody nipple discharge, although the patient can be asymptomatic. Eczematous changes of nipple is commonly associated with Paget disease of breast. Mammographic finding of microcalcification is non-specific and can be seen in many proliferative diseases including usual ductal hyperplasia and ductal carcinoma in situ. Multiple nodular growth is most likely associated with fibrocystic changes. Palpable mass can be a presentation of many benign and malignant breast lesions, such as diabetic mastopathy, fat necrosis, phyllodes tumor, fibroadenoma and invasive carcinomas.
8. E. This cae is characterized by increased small ducts with intact myoepithelial layer in a fibrotic background, consistent with sclerosing adenosis. Radial scar is characterized by a central fibrous core with normal ducts regularly radiating toward periphery, also with intact myoepithelial layers that can be seen by CD10 or p63 stain. Intraductal papilloma usually located at retreareolar area, and has papillary growth with fibrovascular core covered by benign ductal cells. Also see discussions of question 1.
9. D. See discussion of question 8.
10. A. This case is characterized by dilated ducts/lobules filled with relatively monotonous cells with small round nuclei. The myoepithelial cells are intact. These are features of carcinoma in situ, either ductal, or lobular. E-cadherin is positive for ductal but negative for lobular carcinoma in situ. Other markers can be seen in both types, even though Her2 is more likely to be positive in ductal carcinoma in situ and invasive ductal carcinoma.
11. A. See discussions of questions 8 and 10.
12. A. This case is characterized by dilated ducts filled with relatively monotonous luminal cells forming round to oval spaces (cribriform pattern). The contour of these ducts are smooth. CD10 stain reveals the intact myoepithelial layer. These features are consistent with ductal carcinoma in situ. Also see discussion of question 8.
13. A. See discussion of question 10.
14. D. See discussion of question 10.
15. C. This case is characterized by irregular cords of atypical cells invading stroma. Focally there are ductal formation, consistent with invasive ductal carcinoma. Her2 overexpression can be seen in invasive ductal carcinoma and ductal carcinoma in situ, and its status needs to be evaluated due to relevant therapeutic approaches. CK5/6 marks myoepithelial cells. E-cadherin is always positive for invasive ductal carcinoma and ductal carcinoma in situ. P53 can be positive in some cancers. These 3 will not add any useful information, since the diagnosis can be confirmed by morphology already.
16. B. See discussion of question 1.
17. A. This case is characterized by sheets of markedly pleomorphic tumor cells in a background of dense lymphoplasmacytic infiltrate, consistent with medullary carcinoma, a basal like breast cancer that is associated with BRCA mutation and negative for ER, PR, and Her2.
18. E. See discussions of questions 1 and 17. Diffuse large B cell lymphoma do not have cords/sheets of epithelial cells. Indeed the mixed population of CD3+ T cells and CD20+ B cells is most consistent with a non-neoplastic process. Metastatic lung adenocarcinoma is TTF1 negative.
19. B. Medullary carcinoma is a basal like breast cancer that is associated with BRCA mutation and negative for ER, PR, and Her2. Bcl2 mutations are seen in certain lymphomas, including follicular lymphoma. CDH1 mutation is seen in lobular carcinoma, either in situ, or invasive. CHEK2 abnormality can be seen in breast cancer, but usually these cancers are ER positive. Cyclin D1 mutation can be seen some tumors, including mantle cell lymphoma, but not in basal like breast cancer.
20. C. This case is characterized by breast stroma infiltrated by atypical epithelial cells forming single files, consistent with invasive lobular carcinoma. Ductal carcinoma in situ has dilated ducts and atypical cells, and forming various patterns including solid, cribriform, papillary and micropapillary appearance. Invasive ductal carcinoma has ducts with irregular shape and irregular arrangement, suggestive of stromal invasion. Mucinous carcinoma is characterized by clusters of atypical cells floating in mucin pool. Small lymphocytic lymphoma is in the same category of chronic lymphocytic leukemia, characterized by sheets of small lymphocytes with “soccer ball” appearing nuclei, and expression CD5 and CD23, but not cyclin D1. Small lymphocytic lymphoma will not form single files.
21. C. Loss of E-cadherin due to CDH1 mutation is seen in lobular carcinoma in situ and invasive lobular carcinoma. Bcl2 mutations are seen in certain lymphomas, including follicular lymphoma. BRCA1 mutation is seen in basal like carcinoma, including medullary carcinoma. Her2 amplification/overexpression can be seen in invasive ductal carcinoma and ductal carcinoma in situ. MIR15A/MIR16A abnormality can be seen in chronic lymphocytic leukemia.
22. F. This case is characterized by clusters of large pale cytokeratin positive epithelial cells in epidermis, consistent with Paget disease of breast, a malignant tumor associated with underlying malignancies, especially ductal carcinoma in situ. Allergic contact dermatitis has spongiosis and vesicles but not pale atypical epithelial cells. Junctional nevus has nests of benign melanocytes at basal layer without bridges. Melanoma has malignant melanocytes spread in epidermal beyond basal layer. These melanocytes are positive for S-100 but negative for cytokeratin. Invasive ductal carcinoma has ducts with irregular shape and irregular arrangement, suggestive of stromal invasion. Invasive lobular carcinoma has atypical epithelial cells forming single files in stroma.
23. A. See discussion of question 22.
Back to pathology of breast
Back to contents
Comments
Post a Comment