Salivary glands
Primary salivary gland neoplasms
Malignant
Sialoblastoma
Author: Adriana Handra-Luca, M.D., Ph.D.
Last author update: 1 September 2012
Last staff update: 28 December 2022
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PubMed Search: Sialoblastoma salivary glands
Table of Contents
Definition / general | Clinical features | Case reports | Treatment | Microscopic (histologic) description | Microscopic (histologic) images | Cytology description | Positive stains | Differential diagnosisCite this page: Handra-Luca A. Sialoblastoma. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/salivaryglandssialoblastoma.html. Accessed January 16th, 2025.
Definition / general
- Rare malignant tumor, diagnosed at or near birth, resembling epithelial anlage of salivary glands but in arrested state of differentiation (Ann Otol Rhinol Laryngol 1992;101:958, Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2010;109:109)
Clinical features
- Childhood epithelial salivary gland tumor; common among the perinatal tumors
- Occurs in submandibular, parotid or minor salivary glands; also ectopic salivary gland tissue
- Uni or multinodular, 2 - 7 cm, rapid growth
- May recur locally or involve regional lymph nodes; also lung metastases
Case reports
- Girl infant with tumor arising in ectopic salivary gland tissue in cheek (J Plast Reconstr Aesthet Surg 2009;62:e241)
- Boy infant with congenital tumor arising in minor salivary gland of buccal mucosa (Fetal Pediatr Pathol 2011;30:32)
- 3 month old boy with submandibular swelling of insidious onset (J Pediatr Surg 2008;43:e11)
- 3 month old girl with recurrent and metastatic tumor (Rare Tumors 2011;3:e13)
- 18 month old girl with parotid gland tumor (Pediatr Blood Cancer 2010;55:1427)
- 2 year old with 2 cm mass in parotid gland with increasing anaplasia (Am J Surg Pathol 1999;23:342)
- 6 year old girl with recurrent tumor (Acta Cytol 2003;47:1123)
Treatment
- Excision; chemotherapy if cannot completely excise (Pediatr Blood Cancer 2010;55:374); possibly brachytherapy
Microscopic (histologic) description
- Ductules and solid organoid nests of basaloid cells with fine chromatin and cuboidal epithelial cells
- 2 histological patterns: favorable pattern with semiencapsulation of benign basaloid cells with intervening stroma; unfavorable pattern with anaplastic basaloid cells, broad pushing to infiltrative periphery and minimal stroma (Ann Diagn Pathol 2006;10:320)
- Variable necrosis, variable mitotic activity, variable nuclear atypia, no perineurial invasion
Microscopic (histologic) images
Images hosted on other servers:
Recurrent and metastatic tumor
Nests of basaloid cells
Cytology description
- Tight, solid clusters of atypical basaloid cells plus dispersed epithelial and myoepithelial cells with metachromatic magenta hyaline globular material
Positive stains
- Cytokeratin (ductal structures), S100, smooth muscle actin, calponin, p63
- Also AFP, cytoplasmic HER2, p53; Ki67 index increases with recurrence and may predict behavior (Pediatr Dev Pathol 2010;13:32)
Differential diagnosis
- Adenoid cystic carcinoma
- Basal cell adenoma
- Pleomorphic adenoma: may have embryonal structures
- Teratoma
