Langerhans Cell Histiocytosis (LCH) is a type of cancer that can damage tissue or cause lesions to form in one or more places in the body. Langerhans cell histiocytosis (LCH) is a cancer that begins in LCH cells (a type of dendritic cell which fights infection). Sometimes there are mutations (changes) in LCH cells as they form. These include mutations of the BRAF gene. These changes may make the LCH cells grow and multiply quickly. This causes LCH cells to build up in certain parts of the body, where they can damage tissue or form lesions.
For most patients with LCH, standard-of-care vinblastine/prednisone are used as front-line therapy while cytarabine therapy has been used as therapy for patients who develop recurrence. No alternate treatment strategy has been developed for frontline therapy in LCH.
The purpose of this research study is to compare previously used vinblastine/prednisone to single therapy with cytarabine for LCH. We will evaluate the utility of an imaging study called a positron emission tomography (PET) scan to more accurately assess areas of LCH involvement not otherwise seen in other imaging studies as well as response to therapy. We also want to identify if genetic and other biomarkers (special proteins in patient's blood and in patient's cancer) relate to the response of patients LCH to study treatment.
Patient must have biopsy-confirmed diagnosis of Langerhans cell histiocytosis.
Patient must be between 0-21 years of age.
Patient must have a Karnofsky performance score ≥ 50% or Lansky performance score ≥ 50%.
Central Nervous System (CNS) risk lesions/special site disease: patients with single bone sites that are CNS-risk (sphenoid, mastoid, orbital, zygomatic, ethmoid, maxillary, or temporal bones, the cranial fossa, pituitary gland or neurodegenerative disease) or are "special sites" (odontoid peg, vertebral lesion with intraspinal soft tissue extension) require systemic therapy as standard of care and thus are eligible for the study.
Functionally critical lesions: A single lesion not described above which may cause "functionally critical anatomic abnormality" wherein attempts at local therapy (such as surgical curettage or radiation) would cause unacceptable morbidity. These patients may be enrolled with written approval of the Coordinating Center PI or Vice-Chair and documentation of the rationale justifying systemic therapy.
Asynchronous multisite LCH presentation: A patient may also have any single site of disease involvement at the time of enrollment if they previously had at least one other site of LCH disease in the past (which may have been treated with local therapy/surgery as described), as long as no systemic therapy was previously given per protocol guidelines.
Patient may not have severe renal disease (creatinine greater than 3 times normal for age OR creatinine clearance < 50 ml/m2/1.73m²).