Pseudolymphomatous tumid lupus erythematosus of the oral mucosa.

Oral lesions are frequent complications of systemic lupus erythematosus, but only ulceration is included in the 1982 American College of Rheumatology revised criteria. Because the lack of a uniform classification, a range of ulcerative and keratotic lesions are typically described. In this report we describe a unique progressive irregularly cobblestoned and vegetating plaque of the oral mucosa with clinical and histological features mimicking a cutaneous lymphoma. Despite the papillomatous and extensive nature of the lesions and the dense lymphoid infiltrate with follicle formation suggesting a malignant lymphoproliferative process, the slow progression coupled with a mixed cell infiltrate and polyclonality supported a diagnosis of pseudolymphoma. Recognition of this entity is important to prevent diagnosing them as a malignant lymphoma. As well as with the other mucosal lesions in lupus erythematosus, this pseudolymphomatous variant should be added to the disease spectrum.