Acinic cell carcinoma on the lower lip resembling a mucocele.
A 64-year-old woman presented with a 2-week history of an asymptomatic mass involving the lower lip. Histopathological examination showed a well-circumscribed tumour composed of many lobules separated by thin, fibrous connective tissue. Individual lobules were composed of round or polyhedral tumour cells, which had a characteristic finely granular and vacuolated cytoplasm and eccentric hyperchromatic nuclei. Positive staining was observed with Periodic acid-Shiff, and immunohistochemistry for cytokeratin, alpha-1 antitrypsin, and S-100 protein resulting in a final diagnosis of acinic cell carcinoma. Acinic cell carcinoma represents a well-established, although uncommon, entity in the classification of neoplasms of salivary gland origin. The parotid salivary gland is the most frequent site of acinic cell carcinoma, whereas the lip is a particularly unusual site. The unusual presentation of this tumour may lead to confusion with a mucocele. Given these findings, we suggest that acinic cell carcinoma should be considered in the differential diagnosis of any mucocele-like mass on the lower lip.
Cho
J H
JH
Department of Dermatology, Our Lady of Mercy Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea. drchosh@hotmail.com
Yoon
S Y
SY
Bae
E Y
EY
Lee
C N
CN
Lee
J D
JD
Cho
S H
SH
D014408:Biomarkers, Tumor / Q000378:metabolism; D018267:Carcinoma, Acinar Cell / Q000473:pathology*; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008048:Lip Neoplasms / Q000473:pathology*; D008875:Middle Aged; D009078:Mucocele / Q000473:pathology*
D014408:Biomarkers, Tumor