[Cancer-to-cancer metastasis: amelanotic melanoma into renal cell carcinoma].
METHODS
A 54-year old man was admitted because of motor aphasia, behavioral changes and weight loss and suffered from a widely disseminated cancer with unknown primary origin (CUP) syndrome.


METHODS
The autopsy revealed that he was affected by two malignant neoplasms simultaneously: an amelanotic malignant melanoma metastasizing into a localized renal cell carcinoma.


CONCLUSIONS
Cancer-to-cancer metastasis is an exceedingly rare, but well documented phenomenon. This is the third reported case of a malignant melanoma as donor tumor spreading into a renal cell carcinoma. Well-vascularized and slowly growing renal tumors are typical recipients for cancer-to-cancer metastases. The amelanotic character of the melanoma exerted a special diagnostic challenge. Clinical and autopsy findings as well as the immunophenotypical features of the metastatic amelanotic melanoma (HMB-45, Melan-A/MART-1, S100) and the renal cell carcinoma are described with a review of the relevant literature.
Sayk
F
F
Medizinische Klinik I, Universitätsklinikum Schleswig-Holstein, Campus Lübeck. friedhelm.sayk@uk-sh.de
Mahnken
A
A
Stellmacher
F
F
Dalhoff
K
K
Merz
H
H
D001344:Autopsy; D002292:Carcinoma, Renal Cell / Q000098:blood supply / Q000150:complications / Q000473:pathology*; D017809:Fatal Outcome; D006801:Humans; D016130:Immunophenotyping; D007680:Kidney Neoplasms / Q000098:blood supply / Q000150:complications / Q000473:pathology*; D008297:Male; D018328:Melanoma, Amelanotic / Q000098:blood supply / Q000150:complications / Q000473:pathology*; D008875:Middle Aged; D009362:Neoplasm Metastasis / Q000473:pathology