How Do I Diagnose Pediatric Patients’ Skull Langerhans Cell Histiocytosis Lesions?

Background: Langerhans Cell Histiocytosis (LCH) commonly affects pediatric patients, with skull lesions being frequent. Diagnosis typically requires histopathologic confirmation. While surgical resection has been the standard approach, percutaneous fine needle biopsy (FNB) is emerging as a less invasive alternative. Objective: To compare diagnostic performance, complications, procedure availability, hospital stay, and lesion regression outcomes between surgical resection and percutaneous FNB for pediatric skull LCH lesions. Methods: We retrospectively reviewed 35 pediatric cases diagnosed with skull LCH between 2002 and 2024. Diagnostic procedures included surgical resection and percutaneous ultrasound-guided FNB. Data collected included demographics, procedure timing, complications, hospital stay, and follow-up outcomes, with particular focus on lesion regression post-biopsy. Results: Of 35 cases, 26 underwent surgical resection and 9 underwent FNB. Diagnostic accuracy was 100% for surgery and 89% for FNB. The median time from biopsy request to procedure was significantly shorter for FNB (1 day) compared to surgery (12 days). Complications were more frequent in the surgical group (53.8%), including infections and cranial deformities, while no complications were observed in the FNB group. Notably, 4 cases (11%) showed lesion regression; 2 spontaneously regressed, and 2 others after biopsy, including a temporal bone lesion with central nervous system risk that remained disease-free after 17 years. Conclusion: Percutaneous FNB is a safe, effective, and less invasive alternative to surgical resection for pediatric skull LCH lesions, offering faster procedure times, fewer complications, and the potential for lesion regression post-biopsy. This supports biopsy as the first-line diagnostic approach when feasible.