Eccrine porocarcinoma (EPC) is a rare malignant tumor arising from the intraepidermal portion of the eccrine sweat gland duct epithelium or from pre-existing eccrine poroma (EP) [ [1] Mehregan A.H. Hasimoto K. Rahbari H. Eccrine adenocarcinoma—a clinicopathologic study of 35 cases. Arch Dermatol. 1983; 119: 104-114 Crossref PubMed Scopus (320) Google Scholar ], and the precise pathogenesis remains unclear. We have previously reported that activating transcription factor-2- and signal transducer and activator of transcription-3 signaling pathways might contribute to the formation of both EP and EPC [ [2] Chen S.Y. Takeuchi S. Urabe K. Kido M. Hayashida S. Tomoeda H. et al. Overexpression of phosphorylated ATF2 and STAT3 in eccrine porocarcinoma and eccrine poroma. J Dermatol Sci. 2008; 49: 170-173 Abstract Full Text Full Text PDF PubMed Scopus (5) Google Scholar ], but neither factor was able to dissect EPC from EP.