Phase 2 study using low dose cytarabine for adult patients with newly diagnosed Langerhans cell histiocytosis.
Leukemia
; 38(4): 803-809, 2024 Apr.
Article
in En
| MEDLINE
| ID: mdl-38388646
ABSTRACT
Langerhans cell histiocytosis (LCH) lacks a standardized first-line therapy. This single-center, phase 2 prospective study (NCT04121819) enrolled 61 newly diagnosed adult LCH patients with multisystem or multifocal single system disease from October 2019 to June 2022. Subcutaneous cytarabine (100 mg/m2 for 5 days) was administered in 35-day cycles for 12 total cycles. The primary endpoint was event-free survival (EFS). The median age was 33 years (range 18-66). Twelve patients (19.7%) had liver involvement, of which 2 also had spleen involvement. Among 43 patients undergoing next-generation sequencing, BRAF alterations (44.2%) were most frequent, followed by TP53 (16.3%), MAP2K1 (14.0%) and IDH2 (11.6%). MAPK pathway alterations occurred in 28 patients (65.1%). The overall response rate was 93.4%, with 20 (32.7%) achieving complete response and 37 (60.7%) partial response. After a median 30 months follow-up, 21 (34.4%) relapsed without deaths. Estimated 3-year OS and EFS were 100.0% and 58.5%, respectively. Multivariate analysis identified ≥3 involved organs (P = 0.007; HR 3.937, 95% CI 1.456-9.804) and baseline lung involvement (P = 0.028; HR 2.976, 95% CI 1.126-7.874) as poor prognostic factors for EFS. The most common grade 3-4 toxicities were neutropenia (27.9%), thrombocytopenia (1.6%), and nausea (1.6%). In conclusion, cytarabine monotherapy is an effective and safe regimen for newly diagnosed adults, while baseline lung or ≥3 involved organs confers poor prognosis.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Histiocytosis, Langerhans-Cell
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Cytarabine
Limits:
Adolescent
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Adult
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Aged
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Humans
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Middle aged
Language:
En
Journal:
Leukemia
Journal subject:
HEMATOLOGIA
/
NEOPLASIAS
Year:
2024
Document type:
Article
Affiliation country:
Country of publication: