-
Archives of Pathology & Laboratory... Jan 2020Microglandular adenosis is a rare borderline neoplastic lesion of the breast composed of haphazardly located small, round tubules with a single cell layer interspersed... (Review)
Review
CONTEXT.—
Microglandular adenosis is a rare borderline neoplastic lesion of the breast composed of haphazardly located small, round tubules with a single cell layer interspersed within breast stroma and/or adipose tissue. Microglandular adenosis is devoid of a myoepithelial cell layer, and has a characteristic immunophenotype, being positive for S100 and negative for estrogen receptor, progesterone receptor, and HER2/. When associated with cancer, microglandular adenosis and associated invasive carcinoma share the same molecular alterations, including mutation; therefore, microglandular adenosis is considered a nonobligate precursor of triple (HER2/, estrogen and progesterone receptors)-negative breast carcinoma. Microglandular adenosis is an important diagnostic pitfall as it can be easily mistaken for a low-grade invasive carcinoma.
OBJECTIVE.—
To provide a review of the clinicopathologic features of microglandular adenosis and associated invasive carcinoma, with emphasis on key features separating entities in the differential diagnosis.
DATA SOURCES.—
Review of current literature on microglandular adenosis and associated invasive carcinoma and personal experience of authors.
CONCLUSIONS.—
Microglandular adenosis can mimic breast carcinoma; attention to key features, including morphologic-immunophenotypic correlation, is essential in establishing the diagnosis.
Topics: Breast Neoplasms; Female; Fibrocystic Breast Disease; Humans; Precancerous Conditions; Triple Negative Breast Neoplasms
PubMed: 31116044
DOI: 10.5858/arpa.2019-0049-RA -
Human Pathology Dec 2018Microglandular adenosis (MA) of the breast, a benign glandular proliferation, was originally described approximately 35 years ago. The lesion is constituted by small... (Review)
Review
Microglandular adenosis (MA) of the breast, a benign glandular proliferation, was originally described approximately 35 years ago. The lesion is constituted by small glands, all of the same size. Glands are lined by one layer of cuboidal epithelial cells encircled by basal lamina without any evidence of interposed myoepithelial elements. Cells are positive for low-weight keratins and S-100 protein and negative for estrogen receptor, progesterone receptor, and HER-2. Since then, in the years that followed, several malignant lesions all showing microglandular architecture have been regarded either as a precursor or as an equivalent manifestation of MA. The latter has been associated with a large number of malignancies that include ductal carcinoma in situ, lobular carcinoma in situ, ademyoepithelioma, high-grade basal-like carcinoma, adenoid cystic carcinoma, matrix-producing carcinoma, invasive duct carcinoma not otherwise specified, and spindle cell carcinoma, not to mention acinic cell carcinoma. None of the above tumors were identical to MA. Differences mainly rested not only on the specific structure of the small glands but also on the cytological composition and immunohistochemical features of different lesions. Here, a review of the features of MA together with the differential diagnosis with lesions showing microglandular structure is discussed. MA shows similarities to a lesion named microglandular hamartoma/adenosis of the nasal cavity. The relation of the 2 similar lesions is discussed.
Topics: Adult; Aged; Aged, 80 and over; Biomarkers, Tumor; Biopsy; Breast Neoplasms; Cell Proliferation; Diagnosis, Differential; Female; Fibrocystic Breast Disease; Humans; Immunohistochemistry; Mammary Glands, Human; Middle Aged; Precancerous Conditions; Predictive Value of Tests
PubMed: 29949742
DOI: 10.1016/j.humpath.2018.06.025 -
Arkhiv Patologii 2023The presented case describes the difficulties of diagnosis of the breast microglandular adenosis (MGA), taken by clinicians for a malignant process due to the nature of...
The presented case describes the difficulties of diagnosis of the breast microglandular adenosis (MGA), taken by clinicians for a malignant process due to the nature of growth and large size. Criteria for histological and immunohistochemical diagnosis and differentiation of MGA with malignant neoplasms, in particular, with tubular breast carcinoma, are presented. Taking into account the rarity of the pathology and the absence of described cases in the Russian-language literature, the observation is of interest to pathologists and clinicians.
Topics: Female; Humans; Fibrocystic Breast Disease; Immunohistochemistry; Carcinoma, Ductal, Breast; Diagnosis, Differential; Breast Neoplasms
PubMed: 37053352
DOI: 10.17116/patol20238502140 -
Histology and Histopathology Sep 2013Microglandular adenosis is a rare glandular lesion of the breast, which can mimic well-differentiated invasive carcinoma, and is characterized by a haphazard... (Review)
Review
Microglandular adenosis is a rare glandular lesion of the breast, which can mimic well-differentiated invasive carcinoma, and is characterized by a haphazard proliferation of uniform small round glands with open lumina and lacking a myoepithelial cell layer. This lesion has a rather unique immunohistochemical profile characterized by expression of cytokeratins and S-100, and lack of estrogen receptor (ER) and progesterone receptor (PR). The role of microglandular adenosis as a potential precursor of invasive breast cancer has long been a matter of controversy; however, recent molecular analyses have demonstrated that these lesions are heterogeneous at the genetic level, and that at least a subset of microglandular adenosis are clonal and display gene copy number alterations. Importantly, the pattern of genetic aberrations found in microglandular adenosis differs from that of other non-obligate precursors of ER-positive breast cancer. Carcinomas arising in microglandular adenosis are mostly of triple-negative phenotype (i.e. lack of ER, PR and HER2) and express S100, similar to microglandular adenosis. Genetic alterations found in microglandular adenosis have been shown to be similar to those found in synchronous invasive carcinomas. Here we review the clinical, morphological, and molecular features of microglandular adenosis, with an emphasis on its role as a non-obligate precursor of triple-negative breast cancer, and discuss areas for future research endeavors to clarify the clinical and biological significance of these fascinating lesions.
Topics: Breast; Carcinoma, Ductal, Breast; Cell Proliferation; Female; Fibrocystic Breast Disease; Gene Expression Regulation, Neoplastic; Humans; Immunohistochemistry; Precancerous Conditions; Triple Negative Breast Neoplasms
PubMed: 23584829
DOI: 10.14670/HH-28.1099 -
Archives of Pathology & Laboratory... Sep 2007Microglandular adenosis is widely known as a benign breast lesion that can produce a mass. It differs from other types of adenosis by having an infiltrative pattern of... (Review)
Review
Microglandular adenosis is widely known as a benign breast lesion that can produce a mass. It differs from other types of adenosis by having an infiltrative pattern of growth and glands lacking a myoepithelial layer. Although in every other aspect the cells lining the glands are epithelial, they stain strongly with S100 protein. Most cases of microglandular adenosis are resolved after adequate excision, but more recent data suggest that this lesion may be a precursor for carcinoma, with atypical microglandular adenosis being an intermediate lesion. Carcinomas arising in a background of microglandular adenosis, although they may be low grade, are commonly estrogen and progesterone receptor negative, in contrast to most conventional low-grade carcinomas unrelated to microglandular adenosis. They also show immunopositivity for S100 protein, similar to microglandular adenosis. Diagnostic problems include differentiating microglandular adenosis from carcinoma and assessing the extent of the carcinoma component. In this review, we discuss the histomorphologic and immunophenotypic characteristic of the spectrum of microglandular adenosis lesions with emphasis on diagnostic features distinguishing microglandular adenosis from well-differentiated carcinoma, in particular, tubular carcinoma, and assessment of surgical margins of excision in such lesions.
Topics: Breast; Breast Neoplasms; Diagnosis, Differential; Female; Fibrocystic Breast Disease; Gene Expression Regulation, Neoplastic; Humans; S100 Proteins
PubMed: 17824796
DOI: 10.5858/2007-131-1397-BCAIMA -
Radiologic Technology Jan 2022Fibrocystic changes in the breasts are the most common benign breast condition globally, with as many as 50% of women experiencing symptoms during their lifetime. This...
Fibrocystic changes in the breasts are the most common benign breast condition globally, with as many as 50% of women experiencing symptoms during their lifetime. This article explores the types of changes associated with fibrocystic breasts along with signs and symptoms, etiology and possible risk factors, diagnostic techniques, and treatments of fibrocystic breast changes, including lifestyle modifications, cyst drainage, and medications.
Topics: Breast; Breast Neoplasms; Female; Fibrocystic Breast Disease; Humans; Risk Factors
PubMed: 35017277
DOI: No ID Found -
International Journal of Surgical... Oct 2019Microglandular adenosis (MGA) of the breast is exceedingly rare, with only a few case reports and series published to date. Previous studies have elegantly demonstrated...
Microglandular adenosis (MGA) of the breast is exceedingly rare, with only a few case reports and series published to date. Previous studies have elegantly demonstrated the progression of benign MGA to atypical MGA to MGA-in situ carcinoma to invasive carcinoma and therefore suggest MGA as a possible non-obligate precursor lesion to a subset of breast carcinomas. Immunohistochemically, MGA is negative for estrogen receptor (ER), progesterone receptor (PR), and HER2-neu oncoprotein expression, and carcinomas arising in the setting of MGA are often reported to be triple negative. In this article, we present a unique case of an ER+/PR+/HER2- invasive carcinoma associated with MGA and atypical MGA. Our case highlights the diagnostic pitfall of MGA and suggests that MGA is a heterogeneous group of lesions with potential for either luminal-type or basal-type differentiation during progression to breast carcinoma.
Topics: Biomarkers, Tumor; Breast; Breast Neoplasms; Carcinoma, Ductal, Breast; Disease Progression; Female; Fibrocystic Breast Disease; Humans; Mammography; Mastectomy; Middle Aged; Precancerous Conditions
PubMed: 31046496
DOI: 10.1177/1066896919845493 -
Cancer Treatment and Research... 2020Microglandular adenosis (MGA) is a rare benign proliferative lesion lacking a myoepithelial cell layer; 27% of all reported cases have progressed to invasive carcinoma.... (Review)
Review
INTRODUCTION
Microglandular adenosis (MGA) is a rare benign proliferative lesion lacking a myoepithelial cell layer; 27% of all reported cases have progressed to invasive carcinoma. Salivary gland-type carcinomas of the breast are also uncommon, representing 2% of all breast cancers. This wide spectrum of neoplasms tends to be triple negative and generally has an excellent prognosis. Given the rarity of salivary gland-type carcinomas of the breast arising from MGA, there are few reports of these cases in literature. As such, there is uncertainty regarding their diagnosis and treatment strategies.
PRESENTATION OF CASE
We report the rare case of a 66-year-old woman who presented with a triple negative, invasive carcinoma with salivary gland-type features, arising from MGA. The patient underwent mastectomy with sentinel lymph node biopsy, followed by Taxotere and Cyclophosphamide (TC) chemotherapy and 50 Gy in 25 fractions of radiation to her chest wall. We reviewed the available literature on salivary gland-type breast carcinomas arising from MGA.
DISCUSSION
Despite the generally unfavourable characteristics associated with carcinoma arising in microglandular adenosis (MGACA), most patients with MGACA have favourable outcomes.
CONCLUSIONS
The findings of the present case and reviewed cases are consistent with the literature on MGA, atypical MGA (AMGA), and MGACA. Future study of this rare entity is warranted to establish a consensus surrounding its clinical significance and treatment methods.
Topics: Aged; Antineoplastic Combined Chemotherapy Protocols; Breast; Carcinoma, Ductal, Breast; Chemoradiotherapy, Adjuvant; Cyclophosphamide; Diagnosis, Differential; Docetaxel; Dose Fractionation, Radiation; Female; Fibrocystic Breast Disease; Humans; Mastectomy; Sentinel Lymph Node Biopsy; Treatment Outcome; Triple Negative Breast Neoplasms
PubMed: 32454386
DOI: 10.1016/j.ctarc.2020.100178 -
The Breast Journal 2009Microglandular adenosis of the breast is an extremely rare, benign lesion. Carcinoma arising in microglandular adenosis has been reported in up to 27% of patients with... (Review)
Review
Microglandular adenosis of the breast is an extremely rare, benign lesion. Carcinoma arising in microglandular adenosis has been reported in up to 27% of patients with microglandular adenosis. We reported a case of invasive carcinoma arising in microglandular adenosis. A lumpectomy was performed on a 42-year-old female because of a mass in the right breast. Grossly, the lesion was ill-defined with thickened areas. Histologically, this case was consistent with carcinoma arising in microglandular adenosis and showed clear transition from microglandular adenosis through atypical microglandular adenosis to in situ and invasive carcinoma. All the epithelial cells were positive for cytokeratin7, S-100 protein, but negative for estrogen receptor, progesterone receptor, and Her2/Neu. No myoepithelial cells were demonstrable with immunohistochemical staining for smooth muscle actin, muscle-specific antigen or P63. Periodic acid-Schiff staining showed the presence of a basement membrane in microglandular adenosis, atypical microglandular adenosis, in situ carcinoma and the absence in invasive carcinoma. To the best of our knowledge, this is the first reported case of carcinoma arising in microglandular adenosis in China.
Topics: Adult; Breast Neoplasms; Carcinoma, Ductal, Breast; Female; Fibrocystic Breast Disease; Humans; Immunohistochemistry
PubMed: 19824997
DOI: 10.1111/j.1524-4741.2009.00839.x -
The Journal of Pathology Jun 2016Microglandular adenosis (MGA) and atypical MGA (AMGA) are unusual lesions of the breast. They were once regarded as benign proliferative lesions and innocent bystanders....
Microglandular adenosis (MGA) and atypical MGA (AMGA) are unusual lesions of the breast. They were once regarded as benign proliferative lesions and innocent bystanders. Several lines of evidence suggested that they could be neoplastic, clonal lesions and a non-obligate precursor for triple-negative breast cancers (TNBC). Recent work published in The Journal of Pathology by Guerini-Rocco and colleagues provided further evidence regarding the precursor-product relationship between MGA/AMGA and TNBC. Using a massively parallel sequencing approach, they demonstrated that MGA/AMGA, particularly those associated with TNBC, could be clonal neoplastic lesions showing clonal non-synonymous mutations, but none in pure MGA. Importantly, those alterations were observed in the associated TNBC. They were also able to identify recurrent alterations in TP53 in those MGA/AMGA cases as well as their associated TNBC. The findings, in conjunction with others, underscore the significance for MGA in clinical diagnosis. The potential of a benign lesion to progress into an aggressive malignant tumour implies that modification of the current management approach may be necessary. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Topics: Breast; Breast Neoplasms; Carcinoma, Ductal, Breast; Female; Fibrocystic Breast Disease; Humans; Triple Negative Breast Neoplasms; United Kingdom
PubMed: 27061094
DOI: 10.1002/path.4726