Intranuclear inclusions in fine needle aspirates of bronchial low grade mucoepidermoid carcinoma with clear cell change: a report of two cases.
BACKGROUND
Mucoepidermoid carcinoma of the bronchus is a rare neoplasm that can be recognized on histology as well as cytology by the presence of three characteristic cell types: mucus secreting, epidermoid and intermediate. We encountered two cases displaying unusual cytologic features, including clear intranuclear inclusions.


METHODS
Two females, aged 33 and 39, presented with an intrabronchial tumor and pulmonary parenchymatous mass, respectively. Fine needle aspiration of both tumors showed similar cytologic features, with a dominant population of cells with bland nuclei and wide cytoplasm, and frequent intranuclear inclusions. A minor component of mucus-secreting cells was also recognized. Histologically, both tumors corresponded to the clear cell variant of mucoepidermoid carcinoma.


CONCLUSIONS
The cytologic picture in our cases has not been described previously in fine needle aspirates of mucoepidermoid carcinoma, in neither the bronchus nor salivary gland. The differential diagnosis of a monotonous population of epithelial cells with intranuclear inclusions involves bronchioloalveolar carcinoma, but the absence of the characteristic sheet pattern, as well as the clinical and image findings, excludes this possibility. The lack of atypia and intrabronchial location limits the scope to carcinoid and salivary gland-type tumors of the bronchus. Since we were aware of the possibility of unusual cytologic presentations of mucoepidermoid carcinomas, search for different cellular populations suggested the precise diagnosis.
Romagosa
Cleofé
C
Department of Pathology, Hospital Clinic, University of Barcelona, Spain.
Morente
Vanesa
V
Ramírez
José F
JF
Esteve
Roser
R
Alós
Llúcia
L
Cardesa
Antonio
A
Solé
Manel
M
D000328:Adult; D001707:Biopsy, Needle; D001984:Bronchial Neoplasms / Q000473:pathology* / Q000648:ultrastructure; D018277:Carcinoma, Mucoepidermoid / Q000473:pathology* / Q000648:ultrastructure; D002467:Cell Nucleus / Q000648:ultrastructure; D005260:Female; D006801:Humans; D002479:Inclusion Bodies