KEY BISCAYNE, FLA. — Laboratory tests indicated the patient had diabetes insipidus. A bone scan was negative. MRI of his head showed pituitary stalk infiltration and plaques typical of multiple sclerosis. A chest CT scan revealed multiple pulmonary nodules. Both biopsies indicated Langerhans cell histiocytosis (LCH). The patient was diagnosed with stage III LCH with skin, lung, and CNS involvement.
Assess hematologic, pulmonary, hepatic, renal, and skeletal systems to determine extent of disease, Paul A. Krusinski, M.D., suggested at the annual meeting of the Noah Worcester Dermatological Society. Treatment is guided by extent of disease and number of systems involved, added Dr. Krusinski, professor of medicine at the University of Vermont in Burlington.
In cases of single-system skin disease, treatment options include topical steroids, psoralen-ultraviolet-light treatment, and topical nitrogen mustard.
With multisystem involvement, combination therapy with vinblastine and a steroid is most common. Vinblastine plus etoposide, prednisone, and mercaptopurine is more effective than monotherapy. A failure to respond to therapy by 6 weeks indicates a poorer prognosis.
The patient was treated with desmopressin acetate for his diabetes insipidus. He also received six monthly cycles of 2-chlorodeoxyadenosine (cladribine) for the histiocytosis. Cladribine destroys resting and dividing lymphocytes and is approved for treatment of hairy cell leukemia. Cladribine trials for LCH are ongoing; it may be effective at blocking the clonal proliferation of Langerhans cells responsible for the disease. Principal toxicity is from myelosuppression, but long-term malignancy effects are unknown. Another potential treatment is imatinib mesylate.
With single-system disease, 5-year survival is 100%. With multisystem involvement, 5-year survival is 92%. If there is lung disease, 5-year survival drops to 87%.