[Histiocytic lymphoma and pulmonary fibrosis in a female patient with essential thrombocythemia].

The case of a patient with the diagnosis of essential thrombocythemia is presented. Following treatment with melphalan during three years the patient presented clinical and radiologic data of pulmonary fibrosis. Thoracotomy with lung biopsy histologically proving fibrosis was performed. The patient developed a true histiocytic lymphoma afterwards. The rarity of pulmonary fibrosis induced by melphalan and the exceptional association of essential thrombocythemia and histiocytic lymphoma is emphasized. The characteristics of the latter disease, diagnostic difficulties and possible treatment are commented upon.