CCND1 and pachyonychia congenita: Although different molecular markers have been used to enable the differentiation between benign and malignant lesions and to predict the prognosis [13–19], varied results were obtained for these markers, in which some were involved in PC development, such as Cyclin D1 which increases its expression in cases of metastasis development [16], and it was correlated with poor prognosis in tumor cells of the breast, pancreas, esophageal carcinoma, and mantle cell lymphoma [20–23].