Overview and Characteristics of Sclerosing Polycystic Adenosis
- Rare salivary gland tumor
- First described in 1996 by Dr. Brion Smith
- Most commonly affects parotid gland (70% of cases) and submandibular gland
- Presents as mass or swelling in salivary glands in the 5th decade of life
- More common in females than males
- Nearly all cases have a benign behavior
- Rare case reported with malignant transformation
- Histopathological findings similar to fibrocystic changes of the breast
- Well-circumscribed lesions with haphazardly arranged ducts, myoepithelial cells, and acini
- Ducts range from small ductules to cystically dilated spaces, often containing secretion products
Eosinophilic Granules in Sclerosing Polycystic Adenosis
- Presence of bright pink (eosinophilic) acinar granules in all lesions
- Acinar granules are altered zymogen
- Characteristic finding in sclerosing polycystic adenosis
- High power H&E stained image shows eosinophilic granules
- Granules contribute to the unique histopathological appearance of the tumor
Studies and Research on Sclerosing Polycystic Adenosis
- Clinicopathologic analysis of nine cases by Smith et al. (1996)
- Report of 16 cases by Gnepp et al. (2006)
- Examination of three cases with immunohistochemical and ultrastructural analysis by Skalova et al. (2002)
- Case report of invasive carcinoma arising from sclerosing polycystic adenosis by Canas Marques and Felix (2014)
- Demonstration of clonal nature of the tumor using the polymorphism of the human androgen receptor (HUMARA) locus by Skalova et al. (2006)
Review and Emphasis on Intraductal Epithelial Proliferations
- Review of sclerosing polycystic adenosis with emphasis on intraductal epithelial proliferations by Petersson (2013)
- Intraductal epithelial proliferations are a notable feature of the tumor
- Head Neck Pathol journal published a review on this topic
- The review provides additional insights into the nature of intraductal epithelial proliferations
- The review discusses the significance of these proliferations in the diagnosis and management of the tumor.
Miscellaneous
- None of the concepts in this content fall under this category.
Sclerosing polycystic adenosis (also abbreviated SPA) is a rare salivary gland tumor first described in 1996 by Dr. Brion Smith. The major salivary glands, specifically the parotid gland (about 70% of cases) and the submandibular gland, are affected most commonly. Patients usually come to clinical attention with a mass or swelling in their salivary glands in the 5th decade of life, with females affected much more commonly than males. Nearly all of the cases reported so far have a benign behavior (no recurrence and no metastasis), although there is a single case that has had an associated malignant transformation (becoming an invasive cancer).
When reviewed by a pathologist, the findings are quite similar to fibrocystic changes of the breast, although they are different enough, that it is now recognized to actually represent a true neoplasm (clonal proliferation) through various studies. Specifically, the lesions are usually well-circumscribed, containing lobules of haphazardly arranged ducts, myoepithelial cells, and acini that have abundant sclerosing or hyalinized fibrosis. Apocrine change is quite common in the ductal cells. The ducts range from small ductules to cystically dilated spaces (more than 4 striated duct-widths across), often containing products of secretion or reactive histiocytes. A very curious and characteristic finding in all of the lesions is the presence of bright pink (eosinophilic) acinar granules (which are altered zymogen).
