Table of Contents
Definition / general | Clinical features | Treatment | Gross images | Microscopic (histologic) description | Microscopic (histologic) images | Positive stains | Negative stains | Differential diagnosisCite this page: Handra-Luca A. Basal cell adenocarcinoma. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/salivaryglandsbasalcelladenocarcinoma.html. Accessed January 22nd, 2021.
Definition / general
- Low grade malignant counterpart of basal cell adenoma; infiltrative with perineurial invasion and vascular invasion (Mod Pathol 2002;15:298)
- Also called basaloid carcinoma
Clinical features
- 1 - 2% of salivary gland carcinomas
- Malignant counterpart of basal cell adenoma - 23% arise within preexisting basal cell adenomas
- Associated with dermal cylindromas
- Slow growing
- Usually parotid gland, adults, ages 50+, also in minor salivary glands
- No gender predilection
- Locally destructive
- 37% recur locally, 8% metastasize (solid pattern) to lymph nodes, 4% to lungs but death from disease is unusual
Treatment
- Excision with clear margins, radiotherapy for minor salivary gland lesions (Arch Pathol Lab Med 2007;131:1602)
Microscopic (histologic) description
- Low grade malignancy similar to basal cell adenoma but infiltrative with perineurial invasion and vascular invasion
- Multicentric, variable cytologic atypia and mitotic activity
- Two cell types: small cells with scant cytoplasm and dark nuclei (may show palisading pattern) and polygonal cells with eosinophilic / amphophilic cytoplasm and clear nuclei
- Patterns: solid, trabecular, tubular, membranous
- No myxoid matrix, no cyst formation
Positive stains
- CK7+ / CK20- (Mod Pathol 2004;17:407), p53, HER2, CD117 / c-kit (60%, heterogeneous, epithelial cells and not myoepithelial cells, Mod Pathol 2003;16:1224), BCL2, PS100, CEA, EMA, CK7
Negative stains
Differential diagnosis
- Adenoid cystic carcinoma: true cribriform structures, angular and hyperchromatic nuclei or prominent nucleoli, strong muscle marker staining
- Adenosquamous carcinoma
- Basaloid ameloblastoma
- Basaloid squamous cell carcinoma: dysplasia in mucosal epithelium
- Low grade pleomorphic adenocarcinoma
- Pleomorphic adenoma
- Small cell carcinoma