Langerhans Cell Histiocytosis in the Adult Lumbar Spine - A Case Report and Literature Review.

Introduction: Langerhans cell histiocytosis (LCH) in spine is a benign disorder that mainly affects children and is rare in adults. The treatment of LCH in adults is still controversial. The literature is drought with reports regarding management of LCH in adults with pathological fracture. We report a case of LCH at L5 vertebra in an adult patient treated with posterior stabilization, decompression, and anterior corpectomy and reconstruction.

Case Presentation: A 30-year-old manual laborer working in Middle East, presented to us with severe pain in the lower back (VAS-8) with the right lower limb radiculopathy for 6 months. Radiological investigations revealed to have a solitary osteolytic lesion with pathological fracture at L5 vertebral body. MRI showed hyperintense lesion in T2 sagittal images and hypointense in T1 sagittal images in L5 vertebral body. PET scan showed metabolically active lesion involving L5 vertebra body and right ischium. CT-guided biopsy from L5 vertebral body was performed, but was inconclusive. The patient underwent surgical management in the form of posterior stabilization L4-S1 and transpedicular biopsy. The sample was sent for frozen section and confirmed the presence of neoplasia but did not provide sufficient information about the nature of pathology. Intraoperatively, the decision was made to do anterior excision biopsy, corpectomy, and reconstruction with titanium mesh cage filled with cement. The precise diagnosis of LCH was established on histopathological examination and confirmed with immunohistochemistry positivity for CD1a and S100. The patient had immediate relief of his back pain and radicular pain. He was able to resume his daily activities at 1 month after the surgery. At 2-year follow-up patient was asymptomatic and no local recurrence was noticed.

Conclusion: Surgical excisionfor LCH in adults should be considered in patients with refractory low back pain with pathological fracture, neurological deficits, or spinal instability.