Invasive recurrent pleomorphic adenoma of the palate: A case report and literature review

Pleomorphic adenoma (PA) is a salivary gland tumour characterised microscopically by architectural rather than cellular pleomorphism. The neoplasm also has finger-like projections into the pseudocapsule, which clinically has attributed to the high recurrence rate associated with the neoplasm. Vascular and neural invasion have been reported and are regarded as atypical features of the neoplasm. Review of the literature suggests that invasion of bone without malignant transformation by the neoplasm is very rare.

A 28-year-old female was diagnosed with an invasive recurrent PA of the palate, which required en-bloc resection of the left maxilla. The computed tomography scan showed a homogeneous, well-defined, multilocular lesion which extended from the anterior to the posterior of the maxilla. The histological analysis did not report any malignant transformation of the lesion. Although bone erosion is a known feature of this lesion, bone invasion is atypical. This case represents a rare occurrence of an invasive recurrent pleomorphic adenoma.