Intralesional corticosteroid injections in single-system Langerhans cell histiocytosis with maxillomandibular involvement: a systematic review.

Single-system Langerhans cell histiocytosis (LCH) involving the maxillomandibular complex is rare, and optimal management remains controversial. Intralesional corticosteroid injections have been proposed as a minimally invasive alternative to surgery, radiotherapy, or systemic therapy. The aim of this study is to systematically evaluate the effectiveness and safety of intralesional corticosteroid injections for treating LCH of the maxilla or the mandible. A systematic review was conducted according to the PRISMA guidelines, in which PubMed, Embase and Scopus were searched. Eligible studies included English language case reports and case series describing LCH of the mandible and/or maxilla that had been confirmed by biopsy and treated with intralesional corticosteroid injections. Outcomes assessed included the resolution of symptoms, regression of lesions confirmed by radiography, recurrence, and adverse effects. Fifteen studies comprising 28 patients were included. Thirteen patients were treated with triamcinolone acetonide, 13 with methylprednisolone, and two with dexamethasone. Lesions were predominantly unifocal and located in the body or ramus of the mandible. Intralesional corticosteroid therapy was effective in 27 patients. Recurrence was reported in one case 12 months post treatment. Adverse effects were limited to one localised abscess that resolved without sequelae. Intralesional corticosteroid injections are associated with high rates of clinical and radiological improvement in mandibular and maxillary LCH, with minimal morbidity. While the current evidence is limited to low level studies, this approach represents a promising conservative treatment option. Prospective studies with standardised protocols are needed to define its long-term efficacy and role within treatment algorithms.