Cutaneous markers of coronary artery disease

Table 2 Types of acanthosis nigricans

Type	Characteristics
Obesity-associated AN	Most common type of AN
	May occur at any age but more common in adulthood
	Obesity often caused by insulin resistance
Syndromic AN	Defined as AN that is associated with a syndrome, e.g. hyperinsulinemia, Cushing's syndrome, polycystic ovary syndrome, total lipodystrophy
Benign AN	Also referred to as acral acanthotic anomaly
	Thick velvety lesion most prominent over the upper surface of hands and feet in patients who are in otherwise good health
	Most common in dark-skinned people, especially those of African American descent
Drug-induced AN	Uncommon, but AN may be induced by several medications, including nicotinic acid, insulin, systemic corticosteroids and hormone treatments
Hereditary benign AN	AN inherited as an autosomal dominant trait
	Lesions may manifest at any age, infancy, childhood or adulthood
Malignant AN	AN associated with internal malignancy
	Most common underlying cancer is tumor of the gut (90%) especially stomach cancer
	In 25%-50% of cases, lesions are present in the mouth on the tongue and lips
Mixed-type AN	Patients with one type of AN who also develop new lesions of a different type, e.g. overweight patient with obesity-associated AN who then develops malignant AN

AN: Acanthosis nigricans.