RT Book, Section
A1 Sannaa, Ghadah Al
A1 Lazar, Alexander J.
A2 Barnhill, Raymond L.
A2 Crowson, A. Neil
A2 Magro, Cynthia M.
A2 Piepkorn, Michael W.
A2 Kutzner, Heinz
A2 Desman, Garrett T.
SR Print(0)
ID 1178407978
T1 Cutaneous Metastases
T2 Barnhill's Dermatopathology, 4e
YR 2020
FD 2020
PB McGraw Hill Education
PP New York, NY
SN 9780071828222
LK dermatology.mhmedical.com/content.aspx?aid=1178407978
RD 2024/04/19
AB A  metastasis  is  a  neoplasm  that  has  spread  from  its  original  site  such  that  it  is  no  longer  in  continuity  with,  and  often  not  in  close  proximity  to,  the  primary  lesion.  Neoplasms  can  invade  the  skin  by  contiguous  spread  or  may  spread  into  the  skin  by  direct  extension  into  surgical  scars  and  needle  biopsy  tracts,  but  the  usual  pathway  of  regional  or  distant  metastases  is  believed  to  involve  lymphatic  or  blood  vessels.1-3  Such  lymphatic  and  vascular  spread  may  be  not  only  intraluminal  but  also  extravascular  by  means  of  tumor  cell  migration  along  the  abluminal  surfaces  of  vascular  channels.  The  frequency  of  cutaneous  metastases  in  patients  with  cancer  ranges  from  0.6%  to  10.4%  in  various  studies,  accounting  for  approximately  2%  of  all  skin  tumors.4-10  Autopsy  studies  reporting  lower  incidence  rates  ranging  from  1%  to  5.3%  might  underestimate  the  frequency  of  cutaneous  metastases  both  due  to  successful  antecedent  therapy  and  incomplete  postmortem  skin  examination.11  In  a  study  of  4,020  patients  with  metastatic  carcinoma  and  melanoma,  420  patients  (10.4%)  had  cutaneous  metastases,  and  cutaneous  metastases  were  the  first  sign  of  extranodal  metastatic  disease  in  306  patients  (7.6%).10  In  another  study  of  7,316  cancer  patients,  5%  had  skin  involvement.  Skin  involvement  was  the  first  sign  of  cancer  in  less  than  1%  of  patients.9  A  little  more  than  a  third  of  these  rare  patients  had  direct  extension  of  the  primary  cancer  into  the  skin,  a  third  had  local  (satellite)  metastases,  and  only  about  a  quarter  represented  distant  metastases  to  the  skin.  Thus,  although  skin  metastases  are  in  general  relatively  uncommon,  they  can  quite  rarely  be  the  initial  presentation  of  an  internal  malignancy.