Table of Contents
Definition / general | Terminology | Epidemiology | Sites | Clinical features | Prognostic factors | Case reports | Treatment | Gross description | Microscopic (histologic) description | Microscopic (histologic) images | Cytology description | Cytology images | Positive stains | Molecular / cytogenetics description | Differential diagnosisCite this page: Handra-Luca A, Fernandez N. Cystadenocarcinoma. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/salivaryglandscystadenocarcinoma.html. Accessed March 5th, 2021.
Definition / general
- First described in 1968 by Bookbinder (J Am Osteopath Assoc 1968;67:672)
- Rare, invasive tumor with predominantly cystic growth pattern, usually conspicuous papillary component
- Lacks specific histopathologic features of other cystic salivary carcinomas (Barnes: Pathology and Genetics of Head and Neck Tumours, 1st Edition, 2005)
Terminology
- Also called papillary cystadenocarcinoma, mucus producing adenopapillary (nonepidermoid) carcinoma, malignant papillary cystadenoma and low grade papillary adenocarcinoma of palate
- 2005 WHO classification considered low grade salivary duct carcinoma to be a variant of cystadenocarcinoma, designated as low grade cribriform cystadenocarcinoma (LGCCC)
Epidemiology
- < 1% of all salivary gland tumors
- No sex predilection
- Mean age 59 years
Sites
- 65% occur in major salivary glands (mainly parotid)
- Minor salivary gland sites: buccal mucosa, lips, palate are most frequent
Clinical features
- Mean age 59 years, range 20 - 86 years
- Male gender predominance
- Slow growing, compressible, asymptomatic mass
- Often major salivary glands but also lips, buccal mucosa, palate, tongue, retromolar area, floor of mouth, ectopic salivary glands
- Tumors of palate may erode bone
- Usually indolent behavior but occasionally recurs locally or metastasizes to lymph nodes (Ear Nose Throat J 2011;90:E6)
Prognostic factors
- 8% recur locally, 10% have regional lymph node metastases (Ellis: Tumors of the Salivary Glands, 4th Edition, 2008, Am J Surg Pathol 1996;20:1440)
Case reports
- 61 year old man with slow growing mass in floor of the mouth (J Oral Maxillofac Surg 2006;64:864)
- 67 year old man with slowly enlarging sublingual mass (J Oral Maxillofac Surg 2007;65:1223)
Treatment
- Superficial parotidectomy, glandectomy of submandibular and sublingual tumors and wide excision of minor gland tumors
- Bone resection performed only when it is directly involved by tumor
- Radiotherapy for high grade tumors
Gross description
- Multiple cystic spaces, 0.4 to 6 cm, that are variable in size and often filled with mucin
- At least partially circumscribed
Microscopic (histologic) description
- Well circumscribed but not encapsulated
- Invasive, cystic growth pattern, 75% with conspicuous papillary component
- Irregularly arranged cysts filled with mucin
- Ruptured cysts with hemorrhage and granulation tissue are common
- Intervening fibrous stroma
- Small solid neoplastic islands or duct-like structures may be seen
- Well or poorly differentiated, composed of small cuboidal cells, large cuboidal cells, tall columnar cells or mixture (Am J Surg Pathol 1996;20:1440)
- Cell types of lining epithelium include, most often, small and large cuboidal and columnar cells, occasionally mucous, clear and oncocytic cells
- Typically bland nuclei with conspicuous nucleoli and rare mitoses
- Does not involve the native duct system
- Diagnostic criteria: cysts and smaller duct-like structures at least focally infiltrate the salivary parenchyma and surrounding connective tissue
- Variants include mucinous (aggressive, Auris Nasus Larynx 2005;32:301, Acta Cytol 2001;45:605), oncocytic (children), papillary (low grade, often in minor salivary glands, Int J Surg Pathol 2008;16:341, Auris Nasus Larynx 2007;34:259)
Microscopic (histologic) images
Cytology description
- Ball-like, cohesive, overlapping cells, vacuolated cytoplasm (Diagn Cytopathol 2010;38:377)
Positive stains
- Tumor is composed of cells with ductal differentiation: pancytokeratin+, EMA+
- Carcinoembryonic antigen, variable CA19-9 and CA125
- Vimentin (usually), NSE (usually) (Int J Oncol 1994;4:587)
- S100 (variable intensity)
- MAM6, MAM3, lysozyme, lactoferrin, alpha-1-antichymotrypsin
Molecular / cytogenetics description
- Usually no HER2 amplification (Pathology 2011;43:459)
Differential diagnosis
- Cystadenoma: lacks infiltrative growth into salivary parenchyma or surrounding tissues
- Low grade mucoepidermoid carcinoma: usually has variety of cell types and areas that are more solid than cystic
- Papillary cystic variant of acinic cell carcinoma: acinar differentiation and a greater degree of epithelial proliferation