Improved outcome in the treatment of pediatric multifocal Langerhans cell histiocytosis: Results from the Japan Langerhans Cell Histiocytosis Study Group-96 protocol study.
BACKGROUND
The treatment outcome of multifocal childhood Langerhans cell histiocytosis (LCH) has not been satisfactory and has resulted in poor therapeutic responses with high mortality and a high incidence of reactivation with late sequelae. To overcome these issues, the Japan LCH Study Group-96 (JLSG-96) protocol was conducted prospectively from 1996 to 2001 in Japan.


METHODS
Newly diagnosed children with multifocal LCH were classified into 2 groups: a single-system multisite (SS-m) group and a multisystem (MS) group. All patients initially were treated on Protocol A, which consisted of 6 weeks of induction therapy with combined cytosine arabinoside, vincristine (VCR), and prednisolone (PSL) followed by 6 months of maintenance therapy. Patients who had a poor response to the induction of Protocol A were switched to a salvage regimen (Protocol B), which consisted of an intensive combination of doxorubicin, cyclophosphamide, VCR, and PSL.


RESULTS
In total, 91 patients were treated, including 32 patients in the SS-m group and 59 patients in the MS group. At the median 5-year follow-up, 96.9% of patients in the SS-m group and 78.0% of patients in the MS group had good response status. Diabetes insipidus developed in 3.1% of patients in the SS-m group and in 8.9% of patients in the MS group. The overall survival rate at 5 years for the SS-m and MS groups was 100% and 94.4% +/- 3.2%, respectively.


CONCLUSIONS
The JLSG-96 protocol attained very low mortality for pediatric patients with multifocal LCH.
Morimoto
Akira
A
Department of Pediatrics, Kyoto Prefectural University of Medicine, Graduate School of Medical Science, Kyoto, Japan. akira@koto.kpu-m.ac.jp
Ikushima
Satoshi
S
Kinugawa
Naoko
N
Ishii
Eiichi
E
Kohdera
Urara
U
Sako
Masahiro
M
Fujimoto
Junichiro
J
Bessho
Fumio
F
Horibe
Keizo
K
Tsunematsu
Yukiko
Y
Imashuku
Shinsaku
S
D000293:Adolescent; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006646:Histiocytosis, Langerhans-Cell / Q000188:drug therapy* / Q000453:epidemiology; D006801:Humans; D007223:Infant; D007564:Japan; D008297:Male; D015996:Survival Rate; D016896:Treatment Outcome