Dermoscopy and ultrosound monitoring actinic keratosis with cutaneous squamous cell carcinoma: A case report and literature review

•Actinic keratosis(AK) is a common premalignant skin lesion that can progress to invasive squamous cell carcinoma.•Patients with AK should be diagnosed and treated as early as possible.•Dermoscopy and ultrasound can be very useful in diagnosing and monitoring skin diseases non-invasively.•PDT can be highly recommended as an effective treatments for patients with AK. Actinic keratosis(AK) is a common premalignant skin lesion that can progress to invasive squamous cell carcinoma(iSCC). Clinically, AK presents as reddish or brownish macules, papules, or hyperkeratotic plaques. AK cannot be reliably predicted whether it will transform into invasive carcinomas, so skin biopsy is currently a gold standard for identifying suspicious malignancy. Currently, there are non-invasive methods to help diagnose and determine the difference between AKs and iSCC. For example, dermoscopy and ultrasound can be very useful in diagnosing and monitoring skin diseases non-invasively. Therefore, we report a case of multiple facial AKs with poorly differentiated skin squamous cell carcinoma, which was diagnosed early through dermoscopy and ultrasound, and confirmed by histopathology.