Los Angeles Society Of PathologistsLos Angeles Society Of Pathologists

Dr. Shobha Castelino PrabhuDr. Shobha Castelino PrabhuLoma Linda University Medical CenterLoma Linda University Medical Center

June 12, 2007June 12, 2007

CASE 1CASE 176 year-old gentleman

Status post right parotidectomy 1 year ago for a

“rare tumor”

Presents with a right 5 cm pre-auricular and a 3 cm post-auricular mass - both are firm and immobile

Right facial nerve partial paralysis with tingling sensations

Fine needle aspiration was performed

Followed by excision of both masses

FNA

FNA CYTOLOGYFNA CYTOLOGY

Biphasic cell population around tubule-like structures: inner small dark cells

outer large pale cells

Dense refractile ground substance within tubules

Acellular myxoid/hyaline material present

Multinodular growth

Well circumscribed

Excision

DIAGNOSISDIAGNOSIS

Recurrent epithelial-myoepithelial carcinoma of the parotid gland,

intermediate grade

CASE 2CASE 271 year-old lady awaiting renal transplant

Found to have an irregular spiculated soft tissue density in the left upper lungCT guided needle core biopsy followed by left lung resection

Touch prep

Cytokeratin cocktail

S100

GFAP

S100

DIAGNOSISDIAGNOSIS

Epithelial-myoepithelial carcinoma of salivary gland type, arising in the lung

CASE 3CASE 3

57 year-old gentleman

History of radiation for lung cancer, 2003

Now with large heterogenous liver massCT guided liver biopsy was performed

Touch prep

Liver biopsy

H&E SMA

CK20CK7

DIAGNOSISDIAGNOSIS

Metastatic carcinoma consistent with epithelial-myoepithelial carcinoma

REVIEW OF NORMAL SALIVARY GLAND ANATOMY AND HISTOLOGY

• Major salivary glands: 3 pairs of exocrine secretory glands

• Minor salivary glands: numerous (up to 1000), unencapsulated, distributed throughout mouth, oropharynx, upper respiratory, sinonasal and paranasal tracts

• Function: production and secretion of saliva

• Functional unit: tubuloacinar gland = secretory acinus (sero-mucinous) + duct + myoepithelial cells

Atlas of Tumor Pathology- AFIP

WHO classification of tumoursAtlas of Tumor Pathology- AFIP

Mac DeMay, Practical Princ.of Cytopathology

AFIP classification of salivary gland tumors, third series fascicle

MALIGNANT EPITHELIAL NEOPLASMS BENIGN EPITHELIAL NEOPLASMSMucoepidermoid carcinoma Mixed tumor (pleomorphic adenoma)Adenocarcinoma MyoepitheliomaAcinic cell adenocarcinoma Warthin’s tumorAdenoid cystic carcinoma Basal cell adenomaPolymorphous low-grade adenocarcinoma Canalicular adenomaMalignant mixed tumor Oncocytoma

Carcinoma ex mixed tumor CystadenomaCarcinosarcoma Ductal papillomasMetastasizing mixed tumor Lymphadenomas, sebaceous adenomas

Squamous cell carcinoma SialoblastomaBasal cell adenocarcinomaEpithelial-myoepithelial carcinoma MESENCHYMAL NEOPLASMSClear cell adenocarcinoma BenignCystadenocarcinoma MalignantUndifferentiated carcinomas

Small cell, large cell, lymphoepithelial MALIGNANT LYMPHOMASOncocytic carcinomaSalivary duct carcinoma METASTATIC TUMORSSebaceous adenocarcinoma & lymphadenocarcinomaMyoepithelial carcinoma NON-NEOPLASTIC TUMOR-LIKEAdenosquamous carcinoma CONDITIONSMucinous adenocarcinoma

EPITHELIALEPITHELIAL––MYOEPITHELIAL CARCINOMAMYOEPITHELIAL CARCINOMA

Uncommon (~1%), mainly parotid, primarily in adults (6th -7th decade)

Female > male

Clinically: swelling, pain, facial weakness (palsy)

Gross: well-circumscribed, firm

Micro: biphasic, PAS + material in lumen & cytoplasm (glycogen), <2 mitoses per hpf

EPITHELIALEPITHELIAL––MYOEPITHELIAL CARCINOMAMYOEPITHELIAL CARCINOMA

Immunostains: ductal cells are CK, EMA +clear cells are S100, SMA, HHF35,

GFAP, p63, calponin +EM: electron dense epithelial cells surrounded by electron lucent myoepithelial cellsBehavior: low grade malignancy

40% recurrence14% metastasize (periparotid and cervical nodes, lung, liver, kidney)

Margin statusPoor prognosis- minor salivary gland tumors, atypia (>20%), dedifferentiation, aneuploidy

Treatment: surgical excision +/- radiation

“Biphasic Tumors” :Pleomorphic adenomaAdenoid cystic CAPLGA

“Clear Cell Tumors”:Clear cell carcinoma, NOSMucoepidermoid CAAcinic cell CASebaceous CAOncocytomaMetastatic renal cell, thyroid CA

DIFFERENTIAL DAGNOSISDIFFERENTIAL DAGNOSIS

Bland epithelial cells, and fibrillar, metachromatically staining stroma (“troll’s hair”)

Pleomorphic Adenoma/ Benign Mixed Tumor

www.ym.edu.tw/pat

www. pathology2.jhu.eduepithelial & mesenchymal cells, chondromyxoid stroma

Commonest salivary gland tumor

Follows the rule of 80’s

25% recur if enucleated

www.pathology.uth.tmc.edu

2nd most common malignant parotid tumor, ? commonest malignant minor salivary gland tumor (palate)

Cytology- 3D tight rings surrounding hyaline globules of basement membrane-like material, few bare nuclei/ large myoepithelial cells in background

Cribriform pattern-pseudoglandular spaces filled with cylinders of PAS+ material

Loves nerves!!!

Lung metastases

CD117 positive

Adenoid cystic carcinoma

Rosai and Ackerman’s Surg.Path.Silverberg’s Prin.&Pract. Of Surg. Path

SUMMARYSUMMARY

Rare, low grade carcinomaUsually arising in the parotid glandThree cases of EMC

One typical location (parotid)Two apparently primary in the lung

one metastatic to liver

Important to distinguish from: pleomorphic adenoma because of its potential for metastasisadenoid cystic carcinoma because of its less aggressive nature

REFERENCESREFERENCES

Atlas of Tumor Pathology (Tumors of the Salivary Glands)- AFIP WHO classification of tumours- Head and Neck tumoursElsevier Inc 2004 Rosai and Ackerman’s Surgical Pathology 9th ed.Sternberg's Diagnostic Surgical Pathology 4th ed.Silverberg's Principles and Practice of Surgical Pathology and CytopathologyPathologic Basis of Disease, 7th ed., Robbins and Cotran

Special thanksDr. Craig Zuppan

Dr. Anwar Sultana RazaDr. Wesley Stevens

Dr. Jeff CaoDr. Daniel BuxtonDr. Mingyi Chen

Loma Linda Histology