Extension of Masses Involving the Lacrimal Sac to Above the Medial Canthal Tendon.

Abstract

Retention mucoceles of the lacrimal sac almost always expand below the medial canthal tendon (MCT), whereas the very much rarer malignancies involving the lacrimal sac may progress to form a mass above the tendon. In this study, the incidence of malignancy was determined for patients with a preoperative decision to undergo biopsy for a clinically suspect, hard lacrimal sac mass, together with the proportion having a tumor extending above the MCT. Patients thought-on the basis of having a firm, immobile mass centered on the lacrimal sac fossa-to possibly have lacrimal sac malignancy were identified from a database of biopsies between 1989 and 2020. A retrospective review of their clinical, radiologic, and pathologic records was undertaken. Fifty-three patients (24 male; 45%) underwent biopsy of atypical masses of the lacrimal sac, of which 47 of 53 (89%) extended above the MCT. Seventy-seven percent (41/53) patients had malignancy-26 primary carcinomas and 15 secondary tumors (14 lymphomas or hematopoietic and 1 neuroendocrine)-and 12 had benign conditions (6 transitional cell papillomatosis, 5 chronic inflammation, and 1 solitary fibrous tumor); all the benign pathologies extended above the MCT. The age at presentation and duration of symptoms was similar in patients with benign or malignant pathology. One-fifth of malignant lesions had pain, whereas all the benign conditions were painless, and acute dacryocystitis was relatively uncommon-occurring in only 13% of patients. If a firm and immobile lacrimal sac mass extends above the MCT, it has about a 74% chance of being malignant and, if pain is present, the lesion is more likely to be so. Clinically suspicious masses in the lacrimal sac fossa, whether benign or malignant, appear to present at the same age and with a similar duration of symptoms.