Low-grade sinonasal adenocarcinomas: the association with and distinction from respiratory epithelial adenomatoid hamartomas and other glandular lesions.
Sinonasal adenocarcinomas (SNACs) are uncommon malignancies that show a variety of growth patterns. These lesions are classified as intestinal or nonintestinal, the latter subclassified as low grade or high grade. We have noted that some low-grade nonintestinal SNACs are associated with respiratory epithelial adenomatoid hamartomas (REAHs), also rare lesions that have recently been shown to be neoplastic. We reviewed 29 nonintestinal low-grade SNACs seen at our institution over a 20-year period, with particular attention to morphology and concomitant REAHs. Nine (31%) low-grade SNACs demonstrated a predominantly exophytic and papillary growth pattern, and 18 (72%) had a more tubular growth pattern. Two (7%) were categorized as "other." Six low-grade tubular SNACs were associated with REAHs. An immunohistochemical panel was performed on 2 of these cases; neoplastic cells were immunoreactive with antibodies to CK7 and S100 protein and nonreactive with antibodies to CK20, similar to other low-grade SNACs. No basal cells or myoepithelial differentiation was seen with immunohistochemical stains for p63 and 34betaE12. This association of low-grade tubular SNACs with REAHs suggests that REAHs may be related to some adenocarcinomas.
Jo
Vickie Y
VY
Department of Pathology, University of Virginia, Charlottesville, VA 22908, USA.
Mills
Stacey E
SE
Cathro
Helen P
HP
Carlson
Diane L
DL
Stelow
Edward B
EB
D000230:Adenocarcinoma / Q000150:complications / Q000378:metabolism / Q000473:pathology*; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003937:Diagnosis, Differential; D005260:Female; D006222:Hamartoma / Q000150:complications / Q000378:metabolism / Q000473:pathology*; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D009669:Nose Neoplasms / Q000150:complications / Q000378:metabolism / Q000473:pathology*; D010256:Paranasal Sinuses / Q000378:metabolism / Q000473:pathology*; D020545:Respiratory Mucosa / Q000378:metabolism / Q000473:pathology*