Large cell lymphocytoma.

We studied nine cases of cutaneous lymphoproliferative disease that shared a distinct histologic pattern. The lesions consisted of red-to-violaceous, single or clustered, deep papules or nodules. They proved to be benign on long-term evaluation. Nodular infiltrates of large, pleomorphic lymphocytes, sometimes appearing to be histiocytic and often associated with frequent mitoses, led to the diagnosis of lymphoma or reticulum cell sarcoma in seven of the cases. Sharply marginated, dense clusters of small lymphocytes surrounded or infiltrated the large cell component, a juxtaposition that characterizes large cell lymphocytoma. This pattern was not found in patients with progressive malignant lymphoma. At times, multiple biopsies must be done to establish the diagnosis. All patients are alive, and none has malignant lymphoma. The follow-up periods for six of the patients have been five years or longer.