Clear Cell Syringoid Eccrine Carcinoma / 대한피부과학회지

ABSTRACT

Syringoid eccrine carcinoma (SEC) is a rare adnexal tumor with some controversy surrounding its correct definition. It may also be difficult to differentiate from its benign counterpart (syringoma), other adnexal carcinomas, and cutaneous metastasis from adenocarcinomas. Histologically, the tumor is characterized by syringoma-like tadpole morphology composed of basaloid cells with ductular differentiation. However, the tumor cells are deeply invasive and often extend to subcutaneous tissue, which distinguishes this malignancy from syringoma. Moreover, the tumor cells may rarely show striking vacuolization due to intracytoplasmic glycogen accumulation, called clear cell syringoid eccrine carcinoma. To our knowledge, no case of clear cell SEC in Korea has ever been reported. Herein, we present a case of a SEC (of the clear cell variant) complemented with an immunohistochemical study, the latter revealing cytoplasmic accumulation of glycogen and the presence of intercellular and intracellular lumina in clear tumor cells, as well as diverse hallmarks of SEC.