Chemotherapy for the treatment of single-system and multisystem disease
Chemotherapy is generally used for skin LCH associated with multisystem disease in adults.
A single-center, retrospective review of 58 adult patients with LCH reported on the efficacy and toxicities of treatment with vinblastine/prednisone, cladribine, and cytarabine. Patients treated with vinblastine/prednisone had the worst outcome, with 84% not responding within 6 weeks or relapsing within a year. The no-response/relapse rate was 59% for cladribine and 21% for cytarabine. Grade 3 or 4 neurologic toxic effects occurred in 75% of patients treated with vinblastine. Grade 3 or 4 neutropenia occurred in 37% of patients treated with cladribine and in 20% of patients receiving cytarabine.
Etoposide has been used with some success in single-system and multisystem LCH. Use of prolonged oral etoposide in adults with skin LCH has been reported with minimal toxicity, while 3-day courses of intravenous etoposide (100 mg/m2 /day) achieved complete remission in a small number of patients with resistant single-system and multisystem disease. Another study at the same center found that azathioprine was the most successful drug for localized disease in adults, with the addition of etoposide for refractory and multisystem disease.
For patients who do not respond to front-line therapy with etoposide, cladribine is effective for adults with skin, bone, lymph node, and probably pulmonary and central nervous system (CNS) disease.[24,25] The first study that used cladribine to treat refractory and recurrent skin LCH disease reported on three patients (aged 33, 51, and 57 years) who received two to four courses of cladribine at 0.7 mg/kg intravenously over 2 hours/day for 5 days. In a series of five adults (one untreated and four with refractory LCH treated with cladribine at the same dose noted above), three patients achieved a complete remission and two patients achieved a partial remission.
An adult lymphoma treatment regimen, methotrexate, doxorubicin, cyclophosphamide, vincristine, prednisone and bleomycin (MACOP-B), was used in three patients with multisystem LCH and four with single-system multifocal bone LCH from 1995 to 2007. Total duration of therapy was 12 weeks; response was seen in all patients, two with partial response and five with complete response. Three recurrences were seen after stopping therapy. Despite the small number of patients and the retrospective nature of the study, MACOP-B may be useful as salvage therapy in adult patients with LCH and deserves further study.
Anecdotal reports have described the successful use of the bisphosphonate pamidronate in controlling severe bone pain in patients with multiple osteolytic lesions.[8,9,10]
A case report suggests some benefit to treating neurodegenerative CNS LCH disease with infliximab, a tumor necrosis factor-alpha inhibitor.
A report of stereotactic radiosurgery for the treatment of pituitary LCH in adults showed efficacy in reducing the masses. However, radiation therapy is not considered the standard of care for children with pituitary involvement. Systemic chemotherapy with cytarabine and cladribine have been the preferred treatments.[30,31]