TY  - CHAP
M1  - Book, Section
TI  - Neural and Neuroendocrine Tumors
A1  - Argenyi, Zsolt B.
A1  - Jokinen, Chris H.
A2  - Barnhill, Raymond L.
A2  - Crowson, A. Neil
A2  - Magro, Cynthia M.
A2  - Piepkorn, Michael W.
A2  - Kutzner, Heinz
A2  - Desman, Garrett T.
PY  - 2020
T2  - Barnhill's Dermatopathology, 4e
AB  - During  their  histogenesis,  cutaneous  neural  tumors  either  recapitulate  or  retain  to  a  variable  extent  the  architectural  arrangement  and  cytologic  components  of  the  normal  peripheral  nerve.  Therefore,  familiarity  with  the  normal  histology  of  the  peripheral  nerve  is  essential  for  the  correct  characterization  of  neural  tumors.1  In  short,  the  structural  organization  of  the  peripheral  nerve  follows  a  hierarchical  arrangement  of  different  compartments.  The  basic  unit  is  the  nerve  fiber,  which  is  composed  of  an  axon  (neurite)  and  the  surrounding  Schwann  cells.2  Axons  are  cytoplasmic  extensions  of  neurons  that  are  located  in  the  central  nervous  system  (CNS)  or  in  the  sympathetic  ganglionic  chain.  Axons  become  myelinated  by  multiple  periaxonal  rotations  of  the  surrounding  Schwann  cells,  thus  creating  a  concentric  layer  of  cytoplasmic  membranes.  Unmyelinated  nerve  fibers  develop  by  invagination  of  the  axons  into  the  cytoplasm  of  the  Schwann  cells.  In  the  next  architectural  compartment,  several  nerve  fibers  form  nerve  fascicles  that  are  surrounded  by  a  sheath,  called  a  perineurium.  The  space  within  the  perineurium  is  referred  to  as  the  endoneurium.2  The  perineurium  is  composed  of  a  specialized  cell  type,  the  perineurial  cell,  that  is  in  continuity  with  the  pia-arachnoidal  lining  of  the  CNS.  Besides  the  nerve  fibers,  the  endoneurium  also  contains  fibroblasts,  capillaries,  and  mast  cells.  In  the  final  organizational  compartment,  numerous  nerve  fascicles  are  grouped  into  nerve  bundles  that  are  held  together  by  a  protective  sheath  referred  to  as  the  epineurium.2  The  epineurium  is  made  up  of  fibroblasts,  collagen,  and  adipose  tissue,  but  fine  vascular  structures  also  penetrate  its  wall.  The  sensory  nerves  are  connected  to  various  types  of  sensory  corpuscles  (eg,  pacinian,  meissnerian,  Vater-Pacini,  and  Krause)  that  are  differentiated  to  specific  sensory  perceptions.  
SN  - 
PB  - McGraw Hill Education
CY  - New York, NY
Y2  - 2024/04/19
UR  - dermatology.mhmedical.com/content.aspx?aid=1178407152
ER  -