Fig. 2.

Clinical aspects and histopathological features of actinic cheilitis. a Atrophic regions with blurring of the margin between the affected area and the vermilion border of the lower lip. b Leucoplastic and pigmented areas in the lower lip. c Ulcerated, crusty and leucoplastic lesions with presence of oedema and blurring of the margin between the affected area and the vermilion border of the lower lip. d Presence of an exuberant ulcer in the central region of the lower lip with a leucoplastic border. e Low-grade epithelial dysplasia represented by hyperkeratosis with lack of polarization of basal cells, abnormal variations in nuclear size and shape, and hiperchromatism (H&E, 6 ×). f High-grade epithelial dysplasia represented by irregular epithelial stratification, loss of polarity of basal cells, drop-shaped rete ridges, and loss of epithelial cells cohesion. In addition, abnormal variation is observed in nuclear shape and size, in cell shape and size, hyperchromasia, and increased nuclear/cytoplasmic ratio (H&E, 2 ×). In both images (e, f), it is also possible to observe basophilic degeneration of collagen (solar elastosis) in connective tissue.