Leiomyoma of the caruncle.

A 43-year-old Caucasian male, presented with a swelling of the left caruncle which had persisted for more than ten years. Clinical examination showed a small, smooth, not painful 2x2x2 mm tumor located at the caruncle. There were no signs of orbital involvement. Histologically, the tumor was composed of interlacing fascicles of spindle-shaped cells with bright eosinophilic cytoplasm and cigar-shaped nuclei. Mitotic activity was not observed and the tumor showed no atypia or pleomorphism. The tumor cells reacted with the reticulum stain and Masson trichrome. Immunohistochemically, the tumor cells were positive for vimentin, SMA, MSA, CD34, laminin and a scattered number for S-100. The tumor was classified as a leiomyoma of the caruncle and is the first described in this localisation. The origin of the tumor is discussed.