Biopsy specimens of the skin lesions and lungs showed a granulomatous, angiocentric, angiodestructive infiltrate composed of an admixture of epithelioid histiocytes, small lymphocytes, and medium to large pleomorphic lymphocytes. Cultures of the tissue were negative for fungi, bacteria, and mycobacteria. Immunostaining of the skin and lung biopsy tissue was positive for CD45 (large anaplastic cells), CD20 (large anaplastic cells), CD3 (reactive T cells), and CD43. Taken together, the biopsy findings were consistent with a malignant lymphoma of the large-cell type with B-cell phenotype, associated with numerous reactive T cells and extensive necrosis, so-called lymphomatoid granulomatosis.
A Pig Farmer With Pruritic Pink Papules and Plaques—Diagnosis. Arch Dermatol. 2003;139(6):803-808. doi:10.1001/archderm.139.6.803-a