Currently, numerous epidemiologic studies have linked the risk of PC to various factors like age, ethnicity, family history, insulin-like growth factors, lifestyle, diet, environmental and occupational exposures (4,5). Besides, Kim et al. (6) also reported that chronic inflammation was the cause of PC, playing a vital role in tumor initiation, promotion, malignant transformation, invasion and metastasis. This evidence concerns the gene INS and pachyonychia congenita.