Abstract
Two cases of malignant eccrine tumors with partial squamous differentiation are reported. Case 1 of eccrine porocarcinoma, possibly transformed from pre-existing eccrine poroma, presented symptoms reminiscent of squamous cell carcinoma in the peripheral and invasive area. In case 2 of eccrine ductal carcinoma, the metastatic specimens from the cervical lymph nodes were mainly composed of squamous nests forming keratin cysts, which were only a minor component of the primary tumor. Squamous differentiation in eccrine tumors is thus considered to be one of the important clues indicating malignant transformation.
