Lymphomatoid granulomatosis.

The clinical and pathologic appearance of seven patients with lymphomatoid granulomatosis who had skin lesions when first seen is reviewed. Six patients subsequently developed systemic disease. Although the gross morphology of the skin lesions is variable, the pathology is distinctive. An adequate deep biopsy shows the characteristic lymphohistiocytic infiltrate with variable numbers of atypical cells. Angiodestruction is less evident in the skin compared to other organs. The infiltrate surrounds and invades not only vessels but also nerves and epidermal appendages. The skin biopsy specimen can be differentiated from the lymphomatous infiltrates and Wegener's granulomatosis. Two of the patients who developed systemic disease were diagnosed by skin biopsy but clinicians failed to institute therapy, preferring to wait for other organ involvement. In addition, two patients developed lymphoma, one of which was confirmed at autopsy and one on subcutaneous and bone marrow biopsy 5 years after the initial skin diagnosis. Lymphomatoid granulomatosis can be diagnosed by performing a skin biopsy. Appropriate chemotherapy may result in a high percentage of complete remissions and therefore the dermatopathologist can play an important role in the early diagnosis of this potentially fatal disease.