Table of Contents
Definition / general | Clinical features | Case reports | Treatment | Gross description | Microscopic (histologic) description | Microscopic (histologic) images | Positive stains | Negative stains | Differential diagnosisCite this page: Handra-Luca A. Canalicular adenoma. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/salivaryglandscanalicularadenoma.html. Accessed January 22nd, 2021.
Definition / general
- Distinct monomorphic adenoma with bilayered strands or ribbons of columnar cells with pure luminal ductal epithelial differentiation and loose, well vascularized stroma (Oral Surg Oral Med Oral Pathol 1983;56:608, Cancer 1973;31:1511)
- 1% of salivary gland tumors; 4 - 6% of minor salivary gland tumors (J Oral Pathol Med 2007;36:207)
- 20% of benign minor salivary gland tumors
Clinical features
- Usually arises from minor salivary glands of upper lip or palate (Ann Diagn Pathol 1998;2:224); also parotid gland (Mod Pathol 2002;15:298)
- Female predominance for palate tumors
- Usually ages 50+ years
- Recurrence is uncommon
- Symptoms: pain, multifocal swelling or synchronous bilateral tumors, ulceration
Case reports
- 55 year old woman with tumor of upper lip (Med Oral Patol Oral Cir Bucal 2007;12:E1)
- 61 year old man with tumor of upper lip (Bull Tokyo Dent Coll 2004;45:229)
- 78 year old woman with multiple, bilateral tumors with synchronous occurrence (Clin Exp Dermatol 2009;34:e587)
Treatment
- Excision, radiotherapy
Gross description
- Often encapsulated, 22% multifocal
- Tumor may be received as fragmented specimen
Microscopic (histologic) description
- Bilayered strands or ribbons of columnar cells with loose, well vascularized stroma
- Often basaloid cells or trabecular features
- May infiltrate capsule and exhibit extracapsular tumor islands
- Often cystic change, apocrine, mucous or pigmented cells (Histopathology 1999;35:502)
Positive stains
- S100, AE1 / AE3, CK19, CK7 (Oral Oncol 2001;37:365, Oral Surg Oral Med Oral Pathol 1994;78:761), EMA, vimentin
- Distinctive linear immunoreactive pattern of GFAP among cells in proximity to connective tissue interface (Head Neck Pathol 2007;1:27)
- Focal GFAP, focal CK8; PCNA
Negative stains
Differential diagnosis
- Adenocarcinoma, NOS
- Adenoid cystic carcinoma: destructive infiltration, cribriform pattern, strong muscle markers+
- Pleomorphic adenoma
- Polymorphous low grade adenocarcinoma: vimentin- (Ann Diagn Pathol 2003;7:278), lack of linear GFAP at the tumor / connective tissue interface