Mucoepidermoid Carcinoma of the Lacrimal Sac: Clinical-Pathologic Analysis, Including Molecular Genetics.

PURPOSE

The aim of this study was to assess whether mucoepidermoid carcinoma of the lacrimal sac is a counterpart of gene fusion-related salivary gland mucoepidermoid carcinoma.

METHODS

In this retrospective observational case series, pathology records were searched for all cases of lacrimal sac mucoepidermoid carcinoma diagnosed between 1990 and 2018. Data collected included demographics, clinical findings, management, and follow-up. Pathologic parameters assessed included tumor morphology, immunohistochemistry, and and fluorescence in situ hybridization (FISH) studies.

RESULTS

Six patients with mucoepidermoid carcinoma of the lacrimal sac, 5 males and 1 female, with a median age of 63 years (range 24-66) were identified. Five tumors were managed with radical resection and 1 patient underwent orbital exenteration. None of the patients developed recurrence or metastases with an average follow-up of 18 months (range 13-23). All tumors had morphologic and immunohistochemical features of mucoepidermoid carcinoma and overexpressed EGFR. FISH was negative for rearrangement in all tumors. FISH demonstrated amplification in 1 tumor.

CONCLUSIONS

Mucoepidermoid carcinoma of the lacrimal sac is not a lacrimal sac counterpart of gene fusion-related salivary gland mucoepidermoid carcinoma. pathway activation and amplification in a subset of these neoplasms suggest the potential role for anti-EGFR agents.