Fig. 56. Papillary transitional cell carcinoma of lacrimal sac. A. Papillary carcinoma protrudes into lumen (L) of lacrimal sac. B. High magnification shows papillary transitional cell carcinoma similar to type seen in urinary bladder. Note fibrovascular core in center of each papilla. (From Ryan SJ, Font RL: Primary epithelial neoplasms of the lacrimal sac. Am J Ophthalmol 76:73, 1973.)