Melanonychia associated with subungual follicular inclusions: report of three cases.

Melanonychia is the change in the coloration of the nail plate resulting from the deposition of melanin. Among its causes are melanocytic hyperplasia, melanocytic activation and nail melanoma. Subungual follicular inclusions are histological findings of unknown etiology, possibly related to trauma.

Histopathological analysis of the therapeutic response to cryotherapy with liquid nitrogen in patients with multiple actinic keratosis.

Actinic keratoses are premalignant lesions of the skin caused by excessive sun exposure. Lesions may become mainly squamous cell carcinoma. Cryotherapy with liquid nitrogen is one of the main treatments.