Abstract
Lichen planus-like keratosis (LPLK) is a pathological process, in which seborrheic keratosis or solar lentigo naturally disappears over time.
Here, we report two cases of LPLK in which facial lesions completely disappeared, and compare the dermoscopy findings with the three-stage classification of dermoscopic structures of spontaneous regression of LPLK. During the initial examination, pinkish areas showing inflammatory symptoms and annular granular structures were observed in case 1, annular granular structures were observed in case 2, and both lesions were classified as early stage according to the dermoscopy classification of spontaneous regression of LPLK. The dermoscopic features of case 2 changed with the passage of time, and blue-gray fine dots, which were of the late stage, was observed. The lesions completely disappeared after 2 years and 6 months for case 1 and after 4 years and 4 months for case 2. In the early stage of spontaneous regression of LPLK, annular granular structures were located next to the pinkish area presenting inflammatory symptoms. There were slight differences in the early stage dermoscopic findings between the two cases. As the LPLK lesions change over time, it might be difficult to distinguish them from malignant lesions, and a biopsy might be necessary. However, if the typical annular granular structures of the early stage or regular blue-gray fine dots of the late stage of spontaneous regression were observed, malignant lesions can be ruled out by the dermoscopic findings. When malignant lesions are excluded, spontaneous regression can be confirmed by regular follow-up without a biopsy.
