Abstract

Traditionally, the term metastasis has been reserved for the spread of malignant tumors. However, recent studies have identified the presence of benign tumor tissue within lymph nodes or distant organs outside of the primary site-mimicking the dissemination pattern of malignant neoplasms. As a result, the concept “benign metastasis” has gained attention and is increasingly discussed in the scientific literature. Although several hypotheses have been proposed to explain this phenomenon, it remains a topic of debate. We report a rare case of clear cell hidradenoma with suspected benign metastasis to a lymph node, an uncommon phenomenon that challenges the traditional benign nature of this tumor type. A 69-year-old male presented with a mass in the right inguinal region. Systemic evaluation showed no abnormalities in the liver, lungs, brain, stomach, colon, testes, or prostate. Gross examination revealed a lesion measuring 20 × 15 × 10 mm, with a homogeneous ivory-white cut surface, interspersed with brown speckles. Histopathological and immunohistochemical examinations confirmed the diagnosis of clear cell hidradenoma involving the lymph node. Three months post-surgery, follow-up ultrasound showed no residual lesion, and the surgical site was healing well.