دانلود کتاب موارد بالینی در سرطان پوست کودکان

Langerhans cell histiocytosis is a rare neoplasm of hematopoietic myeloid precursor cells that most commonly affects white male children, with a peak incidence of 1 to 3 years of age. Characteristically, CD1a/S100B/CD207-positive mononuclear cells with bean- shaped nuclei infiltrate single-organ systems, most commonly the bone, but also the skin, or multiple organ systems. Also, approximately 60% of LCH-cells bear a V600E mutation in the BRAF (v-Raf murine sarcoma viral oncogene homolog B) oncogene, and 33% of BRAF wild-type lesions harbor mutations in the MAP 2K1 (mitogen-activated protein kinase 1) gene leading to universal MEK (mitogen activated protein/extracellular signal-related kinase kinase) and ERK (extracellular signal-regulated kinase) activation.