Skin metastasis of internal cancers: a single institution experience

Skin metastatization of internal cancers are rare and a few studies are available analyzing its clinicopathological features. The reported incidence of skin metastasis is influenced by two factors: the relative proportion of cancers covered by skin in the various cohorts and the large differences in the prevalences of various cancer types. Futhermore, the anatomical distribution of skin metastases of various cancer types is aslo not well known. Therefore we have collected a skin metastasis cohort of biopsy and authopsy cases (n = 80) from the archive of our department and analysed its clinicopathologic features. The adjusted skin metastasis prevalence data of various inner cancers indicated that kidney-, lung- and colorectal cancers have a strong positive preference for skin metastatisation while pancreatic cancer has a negative one. We have provided evidences that lower gastrointestinal- and genitourinary cancers preferred infradiaphragmatic skin regions unlike upper gastrointestinal cancers while lung- and kidney cancers preferred supradiaphragmatic regions. We have also detected that ventral skin regional metastasis is slightly more prevalent irrespective of the cancer type. Our study provide the first statistical data for the variations in skin preference of metastatisation among various cancer types as well as for the significant variations in their regional distributions.