Acanthosis Nigricans

Acanthosis nigricans is characterized by hyperpigmented, verrucous or velvety plaques which usually appear on flexural surfaces and in intertriginous regions.

Acanthosis Nigricans (AN) is not an infrequent presentation. The condition sometimes is overlooked by physician and patient. Hence, it could be an occasional sign of internal diseases.

So what are the internal diseases Acanthosis nigricans are related with?