Salivary glands
Primary salivary gland neoplasms
Benign
Basal cell adenoma
Author: Adriana Handra-Luca, M.D.
Topic Completed: 1 September 2012
Minor changes: 19 February 2021
Copyright: 2003-2021, PathologyOutlines.com, Inc.
PubMed Search: Basal cell adenoma[TI] salivary gland
See also: Dermal analogue tumor
Table of Contents
Definition / general | Terminology | Clinical features | Treatment | Case reports | Gross description | Gross images | Microscopic (histologic) description | Microscopic (histologic) images | Cytology images | Positive stains | Differential diagnosis | Dermal analogue tumorCite this page: Handra-Luca A. Basal cell adenoma. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/salivaryglandsbasalcelladenoma.html. Accessed February 27th, 2021.
Definition / general
- Benign tumor resembling pleomorphic adenoma but with basaloid cells and peripheral palisading
- First described by Kleinasser and Klein in 1967
- Also called monomorphic adenoma; excludes canalicular adenoma
Terminology
- Also called dermal analog tumor
Clinical features
- 1 - 2% of epithelial tumors of salivary glands; 2% of benign salivary gland tumors
- Solitary or part of turban tumor, Brooke-Spiegler syndrome
- Usually adults, 2/3 female, mean age 58 years
- Rarely is congenital and resembles embryoma
- Parotid gland or periparotid lymph nodes
- Low recurrence rate
- Rarely transforms; more likely if dermal analogue variant (4% malignant transformation)
- Usually some myoepithelial differentiation using immunostains (Arch Pathol Lab Med 2000;124:401)
Treatment
- Excision
Case reports
- 51 year old man with 6 cm parotic mass of 8 years duration (Case #375)
Gross description
- Encapsulated, often cystic, relatively small
Gross images
Case #375
Microscopic (histologic) description
- Solid, trabecular, trabecular-tubular, membranous or tubular growth of epithelial cells (morphological types) resembling pleomorphic adenoma but with peripheral palisading (Mod Pathol 2002;15:298)
- Basaloid cells, bland cytology, occasional peripheral palisading
- Fibrous stroma present
- Occasionally has acinar cells, squamous whorls or keratinization
- No invasion, no mesenchymal component, no perineurial invasion, no myxoid matrix, no cystic change
Microscopic (histologic) images
Case #375
Various images
Cytology images
Case #375
Various images
Positive stains
- Ductal cells: keratin, alpha-1-antichymotrypsin, CEA, S100 (alpha subunit)
- Basaloid cells: vimentin, actin, S100 (beta subunit)
- Also IL6 (Hum Pathol 1995;26:501)
Differential diagnosis
Dermal analogue tumor
Definition / general
Clinical features
Gross description
Cytology description
Positive stains
Molecular / cytogenetics description
Differential diagnosis
- Uncommon subtype of basal cell monomorphic adenoma with clinical and histological resemblance to dermal cylindroma
- First described in 1974 by Drut and in 1977 by Headington and Reingold (Cancer 1977;39:2460, Cancer 1977;40:1702)
- Also called membranous tumor
Clinical features
- Usually in parotid gland or intranodal parotid gland, ectopic salivary gland in lymph nodes (periparotid, cervical, Cancer 1987;59:1165)
- Sporadic or familial
- Histogenesis: germinal epithelium of ectodermal origin
- Usually men, mean age 60 years old
- 25 - 38% have cutaneous tumors
- Occasionally coexists with multiple dermal cylindromas (Brooke-Spiegler syndrome, autosomal dominant salivary gland - skin adnexal tumor syndrome, Head Neck 2010;32:684), Warthin tumor
- Multicentricity and multiple recurrencies
- Long period of followup required
- Treat with resection but 25 - 37% recur, 28% undergo malignant transformation to basaloid adenocarcinoma with destructive infiltrative growth beyond gland margins and perineurial or vascular invasion but not necessarily pleomorphism, necrosis or mitotic activity
Gross description
- Usually unencapsulated, 50% multifocal, up to 3.5 cm
Cytology description
- Geographic pattern, aggregates of uniform epithelial cells, ill defined cytoplasm, basement membrane-like material (Acta Cytol 2004;48:78, Acta Cytol 1997;41:1015)
Positive stains
Molecular / cytogenetics description
- 16q12-13 abnormality (cylindromatosis gene, CYLD, Am J Surg Pathol 2002;26:778)
Differential diagnosis
- Adenoid cystic carcinoma: more cytologic atypia, hyperchromatic angular nuclei or distinct nucleoli; true cribriform pattern with basophilic matrix
- Basal cell adenocarcinoma
- Basal cell adenoma, solid variant (Acta Otolaryngol 1998;118:588)
- Basaloid squamous cell carcinoma
- Canalicular adenoma
