Symplastic Hemangioma of the Limbal Conjunctiva in a Pediatric Patient With Xeroderma Pigmentosa: A Case Report and Review of Literature.

Symplastic hemangioma (SH) is a rare benign vascular lesion marked by striking nuclear atypia in non-endothelial stromal cells, often mimicking malignancy. It is typically seen in older adults, with only four cases reported to date. Pediatric presentations are exceedingly rare. We present a unique case of limbal SH in a 7-year-old female with xeroderma pigmentosa (XP), who presented with a pigmented conjunctival mass clinically suspected to be malignant. Given the high risk of malignancy in patients with XP-including squamous cell carcinoma and melanoma-SH can pose a diagnostic dilemma. Histological evaluation revealed a polypoidal lesion covered by stratified squamous epithelium, with numerous small blood vessels lined by plump endothelial cells and interspersed bizarre, atypical stromal cells. No necrosis, atypical mitosis, or definitive features of malignancy were identified. Immunohistochemistry showed SMA positivity in the atypical cells, confirming vascular origin, while the Ki-67 index was very low (< 1%), supporting a benign nature. These findings ruled out malignancy despite alarming histological features. To our knowledge, this is the first reported case of limbal SH in a pediatric patient with XP. This case highlights the importance of histopathological and immunohistochemical analysis in distinguishing SH from aggressive vascular tumors and avoiding unnecessary aggressive treatment. It adds valuable insight into the rare spectrum of vascular lesions in XP.