Treatment of bone LCH
As in children, adults with single-bone lesions should undergo curettage of the lesion followed by observation, with or without intralesional corticosteroids. Extensive or radical surgery leading to loss of function and disfigurement is contraindicated at any site, including the teeth or jaw bones. Systemic chemotherapy will cause bone lesions to regress and the involved teeth and jaw bones cannot reform. For those failing chemotherapy, low-dose radiation therapy may be indicated and should be tried before any radical surgery that leads to extensive loss of function and disfigurement. Radiation therapy is also indicated for impending neurological deficits from vertebral body lesions or visual problems from orbital lesions. A German cooperative radiation therapy group reported on a series of 98 adult patients with LCH, most of whom (60 of 98) had only bone lesions, and 24 had multisystem disease including bone, treated with radiation therapy.[Level of evidence: 3iiiDiv] Of 89 evaluable patients, 77% achieved a complete remission, 9% developed an infield recurrence, and 15.7% (14 of 89) experienced a progression outside the radiation field(s).
A variety of chemotherapy regimens, including cladribine, have been published in the treatment of a relatively limited number of patients. (Refer to the Chemotherapy section of this summary for more information.)
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] Successful use of oral bisphosphonates have also been described and may be a useful and relatively less toxic way of treating adult bone LCH. Because of the increased toxicity of chemotherapy in adults, bisphosphonate therapy could be used before chemotherapy in multifocal bone disease. Response of other organs, such as skin and soft tissue, to bisphosphonate therapy has been reported.
Another approach using anti-inflammatory agents (pioglitazone and rofecoxib) coupled with trofosfamide in a specific timed sequence was successful in two patients who had disease resistant to standard chemotherapy treatment.
Treatment of single-system skin disease
- Localized lesions can be treated by surgical excision, but as with bone, mutilating surgery, including hemivulvectomy, should be avoided unless the disease is refractory to available therapy.
- Topical therapies are described in greater detail in the childhood isolated skin involvement section of this summary and include topical or intralesional corticosteroid, topical tacrolimus, imiquimod, psoralen and long-wave ultraviolet A radiation (PUVA), and UVB. Therapies such as PUVA/UVB may be more useful in adults when consideration of long-term toxicity may be less.[15,16,17]
- Systemic therapy for severe skin LCH includes oral methotrexate, oral thalidomide, oral interferon-alpha, or combinations of interferon and thalidomide.[18,19] Recurrences after stopping treatment may occur but may respond to re-treatment.
- Oral isotretinoin has achieved remission in some refractory cases of skin LCH in adults.