LCH-III was a multicenter, prospective, open, phase-III, randomized clinical trial for patients with MS-LCH. Previously untreated patients with MS-LCH were stratified into a “high risk” and a “low risk” group, depending on presence of RO involvement at diagnosis.1
The “high-risk” Stratum aimed to improve initial response and survival by randomized addition of intermediate-dose (500 mg/m2) intravenous methotrexate (MTX) at weeks 1, 3 and 5 to the standard arm of vinblastine and prednisolone. In both randomization arms, a second 6-week course of initial therapy was given in case of insufficient response. Both randomization arms received continuation therapy consisting of prednisolone/vinblastine pulses every 3 weeks and daily oral mercaptopurine for total treatment duration of 12 months, whereas weekly oral methotrexate was added to the experimental arm. Altogether 235 patients were randomized in the “high-risk” Stratum.
In the “low-risk” Stratum the standard combination of prednisolone/vinblastine was randomized for duration of the continuation therapy, namely total treatment duration of 6 months versus 12 months. In the “low-risk” Stratum were randomized 187 patients.
MAIN FINDINGS OF LCH-III:
The cumulative findings of those trials formed the current standard front-line treatment for pediatric-onset multisystem LCH.2,3