Majority of the lacrimal drainage system tumors arise in the lacrimal sac and these can be classified based on histopathology. Table 33.1 provides an overview of the lacrimal sac tumors’ classification. In general, 30–40 % of tumors of the lacrimal sac are benign and 60–70 % are malignant [1–5]. A 70 % of the tumors is of epithelial origin. Most benign lesions are squamous papillomas [6, 7]. A true papilloma demonstrates epithelial papillomatosis and acanthosis, while an inflammatory papilloma demonstrates granulomas. While most neoplasms are sporadic and of random origin, the Human Papilloma Virus (HPV) has been implicated in the pathogenesis of benign neoplasms (HPV 11) and malignant neoplasms (HPV 18). Rarely, a squamous papilloma may undergo oncocytic metaplasia and develop into an oncocytoma [6, 7].

A not so uncommon type, the inverted papilloma, also known as the Schneiderian papilloma, although histologically benign, has a high recurrence rate with malignant potential to a squamous cell carcinoma (10–15 %) and thus should be treated as an aggressive neoplasm. Comprising 0.5–4 % of primary nasal tumors, affecting men more than women, and commonly unilateral, these may either arise de novo or more commonly from involvement from the adjacent nasal cavity of maxillary sinus. While aggressive surgical treatment is indicated, radiation is contraindicated as it may increase the malignant transformation from a benign papilloma to a malignant carcinoma [1–3].

Malignant epithelial tumors commonly include squamous cell carcinoma and transitional cell carcinomas [1–3]. The squamous cell carcinomas have a wide range of differentiation from a well-differentiated to an undifferentiated tumor with corresponding prognoses. Transitional cell carcinomas behave similar to others present in the urinary bladder. Since these tumors have a tendency for intraepithelial spread down to the nasolacrimal duct and nasal cavity, its obligatory to carefully evaluate the nasal cavity and plan management accordingly [1–3]. Amongst carcinomas, mucoepidermoid carcinomas carry a very poor prognosis with almost 0 % 5-year survival rate [8].

Lymphomas are the second-most common primary malignant tumors [2, 9, 10]. They are mostly of the B-cell type and although quite rare, are more common than idiopathic inflammatory pseudotumors. Its occurrence in females has been reported to have a less favorable prognosis. Primary non-Hodgkin’s lymphoma of the lacrimal sac has also been reported in children. Most, however, are diagnosed incidentally during a dacryocystorhinostomy from an altered mucosal appearance or a mass lesion [2, 9, 10].

Primary lacrimal sac melanoma is an extremely rare clinical entity with fewer than 25 cases reported in the literature [1–4]. The incidence of melanomas among lacrimal sac tumors varies between 4 and 13 % in various series [2, 4]. The development of lacrimal sac melanoma has been related to multiple risk factors including: older age, presence of dysplastic moles or nevi, delayed presentation, past history of surgery or interventions like incision biopsy, family history of melanoma, and other sites with cutaneous melanoma [2, 4]. Unfortunately, due to the lack of experience with lacrimal sac melanomas, there are no standard treatment guidelines. Wide surgical excision with tumor-free margins is the preferred treatment. Radiotherapy, chemotherapy, or immunomodulatory agents like alpha-interferon have all been described as an adjuvant modality of management, but with questionable efficacy [1–4].