This is validated by the low Ki-67 in LCH lesions, the Ki-67 positive LCH cells distributed scattered in LCH lesions, taking only about 1.9% of LCH cells, no evidence of in situ proliferation of LCH cells in lesions has been identified [45, 66–68]. The gene discussed is MKI67; the disease is Langerhans cell histiocytosis.