Acanthosis nigricans

Diagnosis: Acanthosis nigricans

Acanthosis nigricans

Clinical Presentation

Acanthosis nigricans

Clinical History

Submitted by Ellie Goulding MD. Originally posted January 23, 2017.

Treatment

See case discussion.

Differential Diagnosis

• Confluent and reticulated papillomatosis (Gougerot-Carteaud) • Epidermal nevus • Terra firma-forme dermatosis • Seborrheic keratosis • Tinea versicolor

Key Learnings

• Most commonly associated with insulin resistance and obesity • Can be a paraneoplastic sign — particularly gastric adenocarcinoma (malignant AN) • Malignant AN tends to be more extensive, rapidly progressive, and involves mucosal surfaces • Distribution: axillae, neck, groin, inframammary folds • Histology shows papillomatosis and hyperkeratosis with minimal acanthosis despite the name • Weight loss and treating underlying insulin resistance may improve the condition

Tags: acanthosis, nigricans, ellie goulding md