Fig. 8

A 56-year-old woman with suspected primary benign bone tumors of the lumbar vertebra. a Preoperative axial CT image demonstrates osteolytic bone destruction in the fifth lumbar vertebra (yellow arrow). b-c: The intraprocedural axial CT image (using bone windows) shows that the biopsy needle is inserted into the bone lesion (yellow arrow). The histopathologic biopsy results (d: hematoxylin and eosin, original magnification 40×, e: hematoxylin and eosin, original magnification 100×) diagnosed the bone lesion as Langerhans cell histiocytosis. Immunohistochemistry showed that the monocyte-like cells were S ≤ 100 (+), CD1a (+), Langerin (+), CD68 (KP1) (−), CD163 (+), CK (−), and LCA (+); the positive rate of Ki-67 was approximately 10%, and acid fast staining was negative. Finally, the surgical histopathology results (f: hematoxylin and eosin, original magnification 40×) of the bone lesion confirmed the diagnosis of Langerhans cell histiocytosis. Immunohistochemistry showed that the cells were CD1a (+), S ≤ 100 (+), Langerin (+), CD68 (KP1) (weak +), and Ki-67 (Li 20%)