RT Book, Section
A1 Harbour, Patrick
A1 Song, David H.
A2 Brunicardi, F. Charles
A2 Andersen, Dana K.
A2 Billiar, Timothy R.
A2 Dunn, David L.
A2 Kao, Lillian S.
A2 Hunter, John G.
A2 Matthews, Jeffrey B.
A2 Pollock, Raphael E.
SR Print(0)
ID 1175965550
T1 The Skin and Subcutaneous Tissue
T2 Schwartz's Principles of Surgery, 11e
YR 2019
FD 2019
PB McGraw-Hill Education
PP New York, NY
SN 9781259835353
LK accessmedicine.mhmedical.com/content.aspx?aid=1175965550
RD 2024/04/19
AB Key  Points  The  epidermis  consists  of  continually  regenerating  stratified  epithelium,  and  90%  of  cells  are  ectodermally  derived  keratinocytes.Pilosebaceous  units  are  lined  by  the  germinal  epithelium  of  the  epidermis  and  thus  serve  as  an  important  source  of  epidermal  regeneration  after  partial-thickness  injury  or  split-thickness  skin  graft.  Dermal  fibers  are  predominantly  made  of  type  I  and  III  collagen  in  a  4:1  ratio.  They  are  responsible  for  the  mechanical  resistance  of  skin.  The  drugs  most  commonly  associated  with  epidermal  necrolysis  include  aromatic  anticonvulsants,  sulfonamides,  allopurinol,  oxicams  (nonsteroidal  anti-inflammatory  drugs),  and  nevirapine.  In  wounds  being  allowed  to  heal  secondarily,  negative  pressure  wound  therapy  can  increase  the  rate  of  granulation  tissue  formation.  Staphylococcus  aureus  is  the  most  common  isolate  of  all  skin  infections.  Impetigo,  cellulitis,  erysipelas,  folliculitis,  furuncles,  and  simple  abscesses  are  examples  of  uncomplicated  infections,  whereas  deep-tissue  infections,  extensive  cellulitis,  necrotizing  fasciitis,  and  myonecrosis  are  examples  of  complicated  infections.  Hemangiomas  arise  from  benign  proliferation  of  endothelial  cells  surrounding  blood-filled  cavities.  They  most  commonly  present  after  birth,  rapidly  grow  during  the  first  year  of  life,  and  gradually  involute  in  most  cases.  Basal  cell  carcinoma  represents  the  most  common  tumor  diagnosed  in  the  United  States,  and  the  nodular  variant  is  the  most  common  subtype.  The  natural  progression  of  basal  cell  carcinoma  is  one  of  local  invasion  rather  than  distant  metastasis.  Squamous  cell  carcinoma  is  the  second  most  common  skin  cancer,  and  typically  arises  from  an  actinic  keratosis  precursor.  Primary  treatment  modalities  are  surgical  excision  and  Mohs  microsurgery.  Cautery  and  ablation,  cryotherapy,  drug  therapy,  and  radiation  therapy  are  alternative  treatments.  Tumor  thickness,  ulceration,  and  mitotic  rate  are  the  most  important  prognostic  indicators  of  survival  in  melanoma.  Sentinel  lymph  node  biopsy  is  often  used  to  stage  individuals  with  biopsy-proven  high  risk  melanoma  and  clinically  node-negative  disease.