Eruptive melanotic macules and papules associated with adenocarcinoma.
BACKGROUND
Malignancies may be associated with paraneoplastic cutaneous manifestations, including pigmentary disorders.


METHODS
The clinical findings were reviewed. Skin and tumor tissue samples were examined by routine histology, immunohistochemistry, and in one case also by electron microscopy.


RESULTS
Two patients developed diffuse melanotic macules and papules associated with visceral adenocarcinoma. One patient was a 64-year-old man with advanced carcinoma of the distal esophagus. The other was a 62-year-old man with metastatic pulmonary adenocarcinoma. The detection of the primary tumor in both patients was preceded by the rapid onset of melanotic macules and papules in the anogenital region and in one patient also around both nipples. The pigmented lesions were histologically characterized by a lentiginous melanocytic proliferation of large and heavily pigmented melanocytes associated with hyperpigmentation of adjacent keratinocytes. Both patients had been misdiagnosed as having epidermotropic metastatic malignant melanoma. None of them had prior, concurrent, or subsequent cutaneous or extracutaneous invasive melanoma. Both patients died of metastatic adenocarcinoma.


CONCLUSIONS
Eruptive melanotic macules and papules represent an under-recognized paraneoplastic syndrome. The cases illustrate a diagnostic pitfall for clinicians and pathologists unaware of this phenomenon.
Busam
Klaus J
KJ
Department of Pathology, Clinical Immunology, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10021, USA. busamk@mskcc.org
Sachs
Dana L
DL
Coit
Daniel G
DG
Halpern
Allan
A
Hwu
Wen-Jen
WJ
D000230:Adenocarcinoma / Q000150:complications / Q000556:secondary*; D001004:Anus Diseases / Q000473:pathology; D014408:Biomarkers, Tumor / Q000378:metabolism; D003937:Diagnosis, Differential; D004938:Esophageal Neoplasms / Q000150:complications / Q000473:pathology*; D017809:Fatal Outcome; D005832:Genital Diseases, Male / Q000150:complications / Q000378:metabolism / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D008175:Lung Neoplasms / Q000150:complications / Q000473:pathology*; D008297:Male; D008545:Melanoma / Q000175:diagnosis; D008548:Melanosis / Q000150:complications / Q000378:metabolism / Q000473:pathology*; D008875:Middle Aged; D009558:Nipples / Q000473:pathology; D010257:Paraneoplastic Syndromes; D010413:Penis / Q000473:pathology; D012867:Skin / Q000378:metabolism / Q000473:pathology; D012871:Skin Diseases / Q000150:complications / Q000378:metabolism / Q000473:pathology*; D012878:Skin Neoplasms / Q000175:diagnosis
D014408:Biomarkers, Tumor