Atypical Facial Chondroid Syringoma of Medial Canthus, A rare clinical entity

Abstract

Abstract Introduction/Objective Chondroid syringoma (CS) is an uncommon, benign mixed tumor originating from the sweat gland. Its incidence rate is extremely low, estimated to be less than 0.01%. CS predominantly affects adult males and shows a preference for the head and neck region. Typically, the size of the lesion is smaller than 1.0 cm, and it presents as a solitary, painless, subcutaneous nodule that is soft to firm, non-ulcerative, and gradually progressive. Histologically, CS is characterized by a neoplasm composed of epithelial and myoepithelial cells, which are surrounded by a myxomatous, pseudochondromatous, or hyaline stroma containing mucous secretions. Although atypia is rare in CS, there is a potential for it to undergo malignant transformation. Methods/Case Report A 49-year-old man presented with a slowly growing mass on the medial canthus that had been present for 6 months. Examination revealed a tender, mobile nodule measuring 1.1 cm. An MRI of the head confirmed a subcutaneous lesion without involvement of deeper structures. Excisional biopsy of the lesion suggested adnexal carcinoma with involvement of the margins. The patient underwent Mohs surgery.Histopathology revealed localized basaloid epithelial proliferation forming solid sheets, trabecular, ductal structures with, chondroid myxoid stroma. Immunohistochemically, the tumor cells of solid sheets and trabeculae were positive for CK5/6, P63, and Vimentin, whereas the cells were focally positive for S100, Calponin, alpha Actin, and SOX10. Also, ductal epithelial cells were highlighted with CK7, Cam5.2, EMA, and CEA. Ki-67 showed 1–5% reactivity. A few satellite nodules with infiltrative margins were seen. The atypical features, including cell atypia and a focal infiltrating border, suggest atypical chondroid syringoma. This tumor is considered a low-grade lesion, and no unequivocal evidence of malignancy has been identified. Results (if a Case Study enter NA) NA Conclusion Awareness of chondroid syringoma as a rare cause of eyelid lesions is important because although it is a benign neoplasm, incomplete excision can lead to recurrence or malignant transformation. Chondroid syringoma rarely exhibits atypia but can convert to the malignant spectrum. When malignant, it has a significant potential for recurrence, metastasis, and even death. Due to the tumor's rarity, making an accurate preoperative diagnosis can be challenging. Therefore, the possibility of chondroid syringoma should be kept in mind when dealing with a gradually progressive, soft to firm subcutaneous swelling.