An immunohistochemical and ultrastructural study of an unusual case of multiple non-X histiocytoma.

An immunohistochemical and ultrastructural study of an atypical case of multiple non-X histiocytoma was done. There was involvement of the skin, lungs, and liver in a 3-month-old male infant. Microscopic examination of the cutaneous tumors revealed a dense infiltration of cells with polymorphous large nuclei and abundant eosinophilic cytoplasm in the entire dermis. Both immunohistochemical and electron microscopic studies suggested that the tumors were non-X histiocytomas. The patient's condition deteriorated with dyspnea due to rapid enlargement of tumor masses in the liver and lungs. However, at 5 months of age, the cutaneous nodules and pulmonary and hepatic lesions showed a tendency to involute. Furthermore, at 12 months of age, they were no longer detectable. The patient at 24 months of age was well with normal development. To date, no recurrence of the disease has been observed.