An intriguing case report of follicular lymphoid hyperplasia of tongue with the detailed review of literature

Follicular lymphoid hyperplasia is a rare reactive benign lesion of the oral mucosa. This is also known as pseudolymphoma as the features mimic the malignant counterpart Follicular lymphoma. In present case, a 34 year old male patient came with a nodular swelling in the posterior–lateral left side of tongue. Medical or dental history was non contributory. Swelling was painless, well demarcated, and about peanut sized. The swelling was provisionally diagnosed as either neurilemmoma, mucocele, or traumatic fibroma. Complete excision was performed, and tissue was sent to a private laboratory. Histopathological findings seen were germinal centers having a core of monotonous cells of the same size and demarcated mantle area mimicking the lymphoma. Immunophenotyping revealed diffused positivity for kappa and lambda expressions. CD10 was diffusely positive in germinal centers and BCl 2 was positive in the mantle area while negative in germinal centers. The final diagnosis given was follicular lymphoid hyperplasia. The entity mentioned in the present paper is an unusual variant of the benign lymphoproliferative lesion and very few cases are reported in the tongue area. Thus, it is important to understand the nature of this benign lesion in all aspects to avoid diagnostic dilemmas due to its malignant mirroring characteristics.