Chronic eosinophilic pneumonia associated with cutaneous T-cell lymphoma

Cutaneous T-cell lymphomas (CTCL) are diseases characterized by cutaneous infiltrates of malignant clonally expanded T cells. CTCL cells exhibit a cytokine profile consistent with T helper-2 type (TH₂) cells. Eosinophilic pneumonias are individual syndromes characterized by eosinophilic pulmonary infiltrates and commonly peripheral blood eosinophilia. CTCL and chronic eosinophilic pneumonia are rare clinical entities. We report a patient with the association of CTCL and chronic eosinophilic pneumonia. To understand the mechanism leading to the eosinophilia, we examined the patient's cytokine profile. This was consistent with a high TH₂ activity. Her interleukin (IL) 5, 6, and 10 levels were extremely high, while her IL-2 and interferon-γ (IFN-γ) levels (TH₁ profile) were low. We believe that eosinophilic pneumonia in this patient is probably secondary to high TH₂ cytokine levels induced by tumor cells. We suggest that eosinophilic pneumonia should be considered as a possible diagnosis in patients with CTCL who have respiratory complaints.