This is a clinicopathologic study of 115 lacrimal sac neoplasms in adults (mean 52 years). The most common presenting signs and symptoms were epiphora (53%), recurrent dacryocystitis (38%), and/or lacrimal sac mass (36%). The tumors were divided into epithelial (82 cases) and nonepithelial (33 cases) neoplasms. Benign epithelial tumors included squamous and transitional cell papillomas (32), oncocytomas (4), and benign mixed tumors (2). The malignant epithelial neoplasms included squamous cell carcinoma (22), transitional cell carcinoma (5), adenocarcinoma (4), mucoepidermoid (3), adenoid cystic (3), and poorly differentiated carcinoma (1). The nonepithelial tumors consisted of fibrous histiocytoma (13), lymphoid lesions (10), malignant melanoma (6), hemangiopericytoma (1), lipoma (1), granulocytic sarcoma (1), and neurofibroma (1). Review of the literature, including our own series, discloses a 55% malignancy rate for tumors originating in the lacrimal sac. Malignant epithelial neoplasms, especially invasive transitional cell carcinoma, often recur locally and can metastasize and be fatal. Epithelial malignancies tend to grow along the epithelium of the lacrimal drainage system, and thus cure is dependent on a wide surgical excision of the tumor and of the entire lacrimal drainage system (canaliculi, sac, and nasolacrimal duct) combined with a lateral rhinostomy and radiation therapy.