Quiz-summary
0 of 1 questions completed
Questions:
- 1
Information
Presented by Dr. Cimino-Mathews and prepared by Dr. Armen Khararjian
This case talks about:
A 60 year-old female presents with a palpable breast mass
You have already completed the quiz before. Hence you can not start it again.
Quiz is loading...
You must sign in or sign up to start the quiz.
You have to finish following quiz, to start this quiz:
Results
Time has elapsed
Categories
- breast 0%
- 1
- Answered
- Review
-
Question 1 of 1
1. Question
Week 632: Case 3
A 60 year-old female presents with a palpable breast mass
Correct
Answer: A. Adenoid cystic carcinoma
Histology: Histologic examination of the breast mass on excision reveals a primarily well circumscribed but focally infiltrative cribriform proliferation of uniform basaloid cells. The cribriform spaces contain pink and blue/myxoid, matrix-like material. Close examination reveals a dual cell population; the basaloid cells comprisethe most numerous cell population, with a smaller population of luminal cells with more eosinophilic cytoplasm that are forming small ducts. There is minimal mitotic activity and no necrosis.
Discussion: The histologic features of this tumor are characteristic of adenoid cystic carcinoma (ACC), which is morphologically identical to ACC in the salivary glands. ACC of the breast is a rare “special subtype” of breast carcinoma. They are typically triple negative tumors (negative for ER, PR and HER2), comprising <0.1% of primary breast carcinomas. By molecular phenotyping, breast ACC classifies as a “basal-like” carcinoma. However, in stark contrast to both salivary ACC and other triple negative breast ductal carcinomas, breast ACC has a favorable long-term prognosis and is generally cured with complete excision. A recurrent translocation t(6;9) between the MYB proto-oncogene and the NFIB transcription factor gene has been described in both salivary and breast ACC, and this translocation can be detected with fluorescence in situ hybridization.
ACC of the breast and salivary gland are comprised of a mixture of myoepithelial/basal cells (p63+, SMA+) and ductal/luminal cells (CK7+, CD117+). They are most commonly cribriform in architecture, but can also be tubular or solid. In the salivary gland, the histologic grading parallels the architecture, such that grade I tumors are primarily tubular/cribriform, grade II tumors have <30% solid architecture, and grade III tumors have >30% solid architecture. The differential diagnosis of cribriform proliferations in the breast includes atypical ductal hyperplasia and ductal carcinoma in situ, invasive cribriform carcinoma (DCIS), collagenous spherulosis, usual hyperplasia, and pseudocribriform adenosis. The diagnosis can be challenging because “myoepithelial markers” such as p63, SMMHC and SMA will be positive in the myoepithelial/basal cells of ACC; the positivity of this immunostains may lead to the mis-diagnosis of a benign or in situ lesion, rather than an invasive carcinoma. The key is to recognize that the basal cells are lining the cribriform spaces containing the basement membrane material. In addition, breast ACC are typically ER-, whereas low grade DCIS and invasive cribriform carcinoma are typically ER+.
References
1. Wetterskog D, Lopez-Garcia MA, Lambros MB, et al. Adenoid cystic carcinomas constitute a genomically distinct subgroup of triple-negative and basal-like breast cancers. J Pathol. 2012 Jan;226(1):84-96.
2. Persson M, Andrén Y, Mark J, et al. Recurrent fusion of MYB and NFIB transcription factor genes in carcinomas of the breast and head and neck. Proc Natl Acad Sci U S A. 2009 Nov 3;106(44):18740-4.Incorrect
Answer: A. Adenoid cystic carcinoma
Histology: Histologic examination of the breast mass on excision reveals a primarily well circumscribed but focally infiltrative cribriform proliferation of uniform basaloid cells. The cribriform spaces contain pink and blue/myxoid, matrix-like material. Close examination reveals a dual cell population; the basaloid cells comprisethe most numerous cell population, with a smaller population of luminal cells with more eosinophilic cytoplasm that are forming small ducts. There is minimal mitotic activity and no necrosis.
Discussion: The histologic features of this tumor are characteristic of adenoid cystic carcinoma (ACC), which is morphologically identical to ACC in the salivary glands. ACC of the breast is a rare “special subtype” of breast carcinoma. They are typically triple negative tumors (negative for ER, PR and HER2), comprising <0.1% of primary breast carcinomas. By molecular phenotyping, breast ACC classifies as a “basal-like” carcinoma. However, in stark contrast to both salivary ACC and other triple negative breast ductal carcinomas, breast ACC has a favorable long-term prognosis and is generally cured with complete excision. A recurrent translocation t(6;9) between the MYB proto-oncogene and the NFIB transcription factor gene has been described in both salivary and breast ACC, and this translocation can be detected with fluorescence in situ hybridization.
ACC of the breast and salivary gland are comprised of a mixture of myoepithelial/basal cells (p63+, SMA+) and ductal/luminal cells (CK7+, CD117+). They are most commonly cribriform in architecture, but can also be tubular or solid. In the salivary gland, the histologic grading parallels the architecture, such that grade I tumors are primarily tubular/cribriform, grade II tumors have <30% solid architecture, and grade III tumors have >30% solid architecture. The differential diagnosis of cribriform proliferations in the breast includes atypical ductal hyperplasia and ductal carcinoma in situ, invasive cribriform carcinoma (DCIS), collagenous spherulosis, usual hyperplasia, and pseudocribriform adenosis. The diagnosis can be challenging because “myoepithelial markers” such as p63, SMMHC and SMA will be positive in the myoepithelial/basal cells of ACC; the positivity of this immunostains may lead to the mis-diagnosis of a benign or in situ lesion, rather than an invasive carcinoma. The key is to recognize that the basal cells are lining the cribriform spaces containing the basement membrane material. In addition, breast ACC are typically ER-, whereas low grade DCIS and invasive cribriform carcinoma are typically ER+.
References
1. Wetterskog D, Lopez-Garcia MA, Lambros MB, et al. Adenoid cystic carcinomas constitute a genomically distinct subgroup of triple-negative and basal-like breast cancers. J Pathol. 2012 Jan;226(1):84-96.
2. Persson M, Andrén Y, Mark J, et al. Recurrent fusion of MYB and NFIB transcription factor genes in carcinomas of the breast and head and neck. Proc Natl Acad Sci U S A. 2009 Nov 3;106(44):18740-4.
