History 47-year-old female who presented with left ear pain. P/E showed a firm lump behind her left ear. Initially she was treated with antibiotics and steroids without effect.
Diagnostic Work-up MRI
of the head and neck showed an enhancing mass in the superficial lobe of the left parotid gland measuring 2.6 x 1.9 x 0.9 cm.
Diagnostic Work-up Two
attempts of FNA were done but no diagnostic material was obtained.
Surgical Treatment The
patient underwent left total parotidectomy.
Gross Exam 2-cm
mass, tan-brown, firm, with infiltrative borders.
PAS-D
Diagnosis:
Comment:
Abluminal cells
Luminal cells
CK19: stains the luminal cells of ducts
CK14: stains the basal cells
p63
S100: strongly stains the myoepithelial cells
Calponin: stains the myoepithelial cells
SMA: stains the myoepithelial cells
cKit: patchy weak staining
cKit: patchy weak staining
Ki67
Criteria for Differential Diagnosis Tumors
with tubular/gland-like pattern Tumors with dual luminal-abluminal cell differentiation.
Polymorphous Low Grade Adenocarcinoma
The tubules are NOT lined myoepithelial cells
Basal Cell Adenoma
Salivary duct carcinoma
Salivary duct carcinoma
Addendum:
Addendum/ Cont’d:
Clinical Follow-up: The
patient underwent postoperative radiotherapy. The most recent CT scan (9/08) showed no evidence of tumor recurrence.
Clear myoepithelial cells
Clear cells & typical morphology Although
the myoepithlial cells typically show clear cytoplasm, they have also been noted to have amphophilic cytoplasm or to appear oncocytic AS WE HAVE IN THIS CASE.
Without clear cells? Epi-myoepithelial
carcinoma without clear
cells Revision
of the classical definition?
Differential Diagnosis
Epi-Myoepi Tumors Adenocarcinoma Tumors with Clear cell Tubualr/glandular tumors pattern
Learning Objectives The
DDx of salivary gland tumors with tubular or gland-like pattern of growth. The significance of dual cell differentiation (luminal and abluminal) in the diagnosis of salivary gland tumors. The significance of cytomorphology and IHC in the distinction between these tumors.
Acknowledgement Dr.
M. Merzianu.