Abstrakt
MEC shows the richest histomorphological diversity among all malignant salivary gland malignancies, with several variants and differentiation features. The diverse morphology makes the diagnosis challenging, without adequate immunohistochemical workup and molecular testing.
This article reports an incidence of colliding two emerging subtypes of mucoepidermoid carcinoma in a 24-year-old male. MRI examination showed a solid ill-defined lesion affecting nearly the whole parotid gland, and it was permeated by the inhomogeneous expansion that was hypointense in T2.
The histologic examination of the excised lesion demonstrated typical histologic features of sclerosing mucoepidermoid carcinoma with tumor-associated lymphoid proliferation formation, colliding with equal proportions of typical Warthin-like mucoepidermoid carcinoma. The neoplastic mucoepidermoid carcinoma cells were immunopositive for p63 and negative for SOX10.
Although the neoplastic areas were not dominant, some areas of necroinflammation, and perineurial invasion were detected and showed positive translocation of MAML2. To conclude, salivary mucoepidermoid carcinoma is a histomorphologically heterogeneous malignancy in which two (or more) subtypes can be detected.
Seeking a second opinion of a surgical pathologist who is well versed in head and neck neoplasia should be considered if the examined lesion shows atypical histomorphologic features.