Acanthosis nigricans

Acanthosis nigricans is characterized by velvety, brown-black plaques, typically located in the axilla and neck. 

It is associated with: 

• Insulin-resistance: 
• Diabetes 
• Acromegaly 
• Cushing syndrome 
• Hypothyroidism 
• PCOS 
• Malignancy – especially gastric adenocarcinoma 
• Other 
• Primary biliary cirrhosis
• Prader-Willi syndrome 
• Medications 
• Glucocorticoids 
• OCP 
• Niacin 

Management

• Treat underlying cause 
• ? retinoids 

References

Higgins, S., Freemark, M. and Prose, N. Acanthosis nigricans: a practical approach to evaluation and management. Dermatol Online j. 2008; 14(9): 2.

Talsania, N. et al. Paraneoplastic Acanthosis Nigricans: The importance of exhaustive and repeated malignancy screening. Dermatol Online J. 2010; 16(8):8.