Oral Lichenoid Lesions Associated With Mediastinal Mass and Hypogammaglobulinemia in a Middle-aged Man

A White man in his 50s with a clinical history of recurrent respiratory infections and diarrhea presented with painful oral erosions that began 2 years before. Results of a previous intestinal biopsy had shown unspecific findings and absence of apoptosis. He reported a 5-kg weight loss that he attributed to impaired intake owing to the oral lesions. He was also being evaluated for a mediastinal mass detected in radiography of the chest performed for pneumonia. Physical examination revealed whitish edematous lacy patches with erosions on the dorsal and lateral aspects of the tongue and buccal mucosa (Figure, A); skin and nails were not involved. A lingual biopsy specimen was obtained for pathologic evaluation and direct immunofluorescence (DIF; Figure, B and C). The result of indirect immunofluorescence (IIF) testing, using monkey esophagus, salt-skin split, and rat bladder as substrates, was negative. Enzyme-linked immunosorbent assay (ELISA) and immunoblot analysis did not detect any desmoglein-1 or -3, bullous pemphigoid-180 or -230, collagen VII, desmocollin-1 to -3, laminin-332, envoplakin, or periplakin antibodies. Results were normal for liver function; negative for hepatitis B and C; indicative of hypogammaglobulinemia, with a decreased immunoglobulin (Ig) G serum level of 465 mg/dL (normal, 750-1600 g/L; for g/L, multiply by 0.01); and normal for IgA and IgM levels. Positron emission tomography revealed a 10-cm hypercapturing extrapulmonary mass (Figure, D). Surgical excision of the mediastinal mass was performed; its histopathologic features were consistent with a type AB thymoma, Masaoka-Koga stage 2A.