Sclerosing polycystic adenosis is a rare pathological lesion that affects salivary glands. The majority of cases involve the parotid and its occurrence in minor glands is exceedingly rare. Here, we report the first case of this lesion in the retromolar pad area and discuss its histological features and immunohistochemical reactivity with
To the best of our knowledge, 54 cases of sclerosing polycystic adenosis (SPA) of salivary glands have been reported. SPA characteristically arises in the major glands, and the majority of cases involve the parotid [
A 60-year-old male presented with swelling in his retromolar pad area with two months’ duration. There was no tenderness or ulceration. Excisional biopsy of the lesion was performed and a well-circumscribed soft tissue lesion was excised. Histopathologic examination showed lobules of hyalinized connective tissue with epithelial components of ductal and acinar differentiation. Ductal structures formed variably sized cysts or they were packed as small ducts similar to the sclerosing adenosis of the breast. Ducts were lined by flattened to cuboidal epithelial cells and some cells had apocrine metaplasia. Mucous cells were frequently seen (Figures
Large cystic spaces and cribriform structures were present throughout the lesion (×100).
Apocrine metaplasia was evident throughout the lesion (×400).
Mucous cells were frequently seen (×400).
Immunohistochemical staining for
Immunohistochemical examination with
Less than 1% of lesional cells were immunoreactive for Ki-67 antibody (×400).
There is a controversy whether SPA is a neoplasm or reactive lesion. Clonal nature of cells has been demonstrated in some cases [
Reports of cytological atypia or dysplasia within some SPA have added to controversies about the nature of this lesion. Atypia may be found within the ductal epithelial cells ranging from mild to severe dysplasia and carcinoma in situ. However, the lobular architecture is always maintained and invasive carcinoma has not been identified in SPA cases [
SPA has diverse histological features. This lesion has a strong resemblance to the fibrocystic disease of breast [
Some authors have investigated immunohistochemical staining profile of cells in SPA. A review of previous studies is presented in Table
A review of immunohistochemical investigations in SPA cases.
Investigators | Markers | Immunohistochemical reactivity |
---|---|---|
Fulciniti et al. (2010) [ |
Collagen IV | Enhanced lobular architecture |
Cytokeratin 14 | Enhanced the ratio of apocrine cells present in the epithelial lining of lobular structures | |
Gross cystic disease fluid protein (GCFDP) | Sebaceous cells | |
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Gurgel et al. (2010) [ |
Ki-67 | Positive in less than 1% of cells |
CKAE1/AE3, EMA, GCDFP-15 | Tubuloacinar elements | |
Estrogen, progesterone, and CK 34 |
Negative | |
SMA, S100 | Myoepithelial layer | |
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Swelam (2010) [ |
S100 | Lesional ductal and spindle-shaped cells |
Bcl-2 | Strong, diffuse cytoplasmic immunoreactivity in basal cells of neoplastic cells | |
Ki-67 | Sporadic positivity in Basal cells of neoplastic ductal epithelium | |
EBV | Expression in neoplastic S100 positive cells | |
HPV-1 | Negative | |
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Meer and Altini (2008) [ |
P63 | Peripheral layer of cells surrounding acini, ducts, and cystic spaces outlining these structures |
AE1/AE3 | In ductal lining cells of tubuloacinar elements | |
S100 | Ductal cells and spindled myoepithelial cells | |
AE1/AE3, CAM5.2, EMA, antimicrobial antibody, BRST-2, S100 | Luminal cells | |
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Bharadwaj et al. (2007) [ |
Cytokeratin | In ductal and acinar elements |
SMA, S100 | Myoepithelial layer | |
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|
CKAE1/AE3 | Positive in ductal and acinar cells |
EMA, S100, antimitochondrial antibody | Variably positive | |
CEA, p53, and HER-2/neu | Negative | |
GCDFP-15 | Acinar cells with coarse eosinophilic cytoplasm | |
Progesterone receptors | Positive in 15% to 20% of epithelial cells | |
Estrogen receptors | At least focally in 5% of ductal cells in dysplastic and hyperplastic foci | |
SMA, P63, and calponin | Myoepithelial layer | |
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Gnepp et al. (2006) [ |
Calponin, SMA, muscle specific actin, S100 | Myoepithelial layer |
SPA is treated with conservative surgical excision with tumor-free margins and recurrence is rarely encountered [
The authors declare that there is no conflict of interests regarding the publication of this paper.