Lymphomatoid papulosis: A challenge in the differential diagnosis of ulcerative lesions of the oral mucosa

Lymphomatoid papulosis (LyP) is a primary cutaneous CD30+ lymphoproliferative disorder, with a higher incidence in males. Despite its benign and self-resolving clinical course, it exhibits histological features that may mimic other conditions. Mucosal involvement in LyP represents an atypical presentation. We report the case of a 50-year-old man with oral and genital mucosal lesions, initially diagnosed as Behçet's disease. Following a systematic review, 35 additional cases of LyP with mucosal involvement were identified, more frequently in women and with a predilection for the tongue. In 55% of patients, mucosal involvement constituted the initial manifestation of the disease, leading to diagnostic delays and misdiagnosis in one-third of cases. The prognosis was similar to that of classic LyP, with no increased risk of secondary neoplasms. Regarding therapeutic management, methotrexate and topical corticosteroids emerged as the main treatment options.