Author(s): Yuji Ohtsuki, Yasuki Hachisuka, Yuhei Okada, Yuki Teratani, Gang-Hong Lee, Mutsuo Furihata
Multiple eccrine spiradenomas (ES) including benign and malignant lesions in a single pa-tient are extremely rare. In the present study, a detailed investigation of multiple nodular ESs is reported in a Japanese woman in her late sixties. A tumor extirpated from the back consisted microscopically of more than 10 separate micronodules, each less than 7mm in size. Each of the small nodules was clearly a benign ES, but the largest one, which was 7mm in diameter, exhibited massive necrosis and hemorrhage. In addition, a microinvasive pattern was also detected, as well as mitotic figures and disordered arrangement of tumor cells. In particular, many CD1a-positive Langerhans cells were detected not only in the largest one, including areas of necrosis in it, but also in the multiple benign ESs. This largest necrotic nodule, associated with multiple nodular benign ESs, was considered a low-grade malig-nancy, although no metastasis or recurrence of it has thus far been detected. Although ESs are usually benign, low-grade malignant or malignant ESs do exist, some of which exhibit or are associated with necrosis or metastatic foci.