Follicular lymphoid hyperplasia of the hard palate and oral mucosa: reportof three cases and a review of the literature

Aims: To bring to wider attention this uncommon, poorly understood entity w hich may closely resemble, clinically and morphologically, follicular lymph oma. Methods and results: We report three cases of follicular lymphoid hyperplas ia of the hard palate and oral mucosa which caused diagnostic difficulties for the referring pathologists. The clinicopathological features are descri bed and integrated into a review of the 16 previously recorded cases. The c ondition most commonly presents as a slowly growing mass situated in the po sterior hard palate but may present with multicentric oral lesions and lymp hadenopathy. Morphologically, it is characterized by a dense follicular lym phoid infiltrate within the lamina propria which may show the classical fea tures of benign reactive hyperplasia, but not uncommonly, indistinct germin al centres, ill-defined mantles and a lack of tingible-body macrophages are features which may lead to an erroneous diagnosis of follicular lymphoma. Conclusions: Follicular lymphoid hyperplasia of the palate is a poorly reco gnized entity which is frequently confused with follicular lymphoma. Awaren ess of the entity combined with the use of immunohistochemistry for immunog lobulin light chains and bcl-2 protein allows a correct diagnosis to be mad e avoiding extensive investigation and aggressive treatment to the patient.