A 72-year-old man who had an unknown recurrent lesion in his lower right eyelid for 8 months was referred to our department. Two prior biopsies revealed a nevoid lesion and dermatofibroma. The patient was referred to our clinic when the tumor recurred. His best-corrected visual acuity was 0.8 OD. A 20-mm × 6-mm multinodular, ulcerated tumor was present on his right lower eyelid (Figure 1). The anterior chamber and the vitreous were free of inflammation and the lens revealed a mild senile cataract. Thepatient underwent sufficient surgical resection with a 4-mm–wide tumor-free margin and reconstruction using a tarsoconjunctival flap combined with a skin graft. Microscopically, the tumor consisted of medium to large spindle-shaped cells with hyperchromatic nuclei. The cells were arranged in fascicles and formed whorls. The mitotic count was high (Figure 2). The final diagnosis was interdigitating dendritic cell sarcoma. The tumor cells strongly expressed S-100 protein, and many tumor cells showed reactivity with antibodies to lysozyme and CD68 as well as CD45 (Figure 3). Numerous small, reactive CD3-positive T lymphocytes were mixed. Some tumor cells were positive for CD83 and fascin. No reactivity was seen with antibodies to cytokeratins, HMB-45, Melan-A, or CD1a or as markers for follicular dendritic cells, such as CD21, CD23, and CD35. The tumor staging revealed no metastatic disease. After careful deliberation of treatment options with his oncologist, the patient declined chemotherapy and local radiation therapy. Two years later, the patient had a local recurrence and metastatic lung and liver disease. A biopsy of a presumed metastasis in the lung confirmed the diagnosis. His clinical condition deteriorated and he died rapidly.