Two cases of primary malignant melanoma of the lacrimal sac

Background. Malignancy of the lacrimal sac is rare, and primary malignant melanoma in this region is extremely rare. Methods. We report two cases of malignant melanoma of the lacrimal sac presented with epiphora and a palpable mass in the medial canthal area. We performed radical surgery and radiation therapy. Results. The light microscopic, immunohistochemical, and electron microscopic studies confirmed the diagnosis. One of the patients, a 65-year-old-woman, has no evidence of recurrence or distant metastasis 3 years after surgery and radiotherapy, whereas another patient, a 56-year-old man, died of distant metastasis 6 months after surgery and radiotherapy. Conclusions. We present two cases of malignant melanoma of the lacrimal sac that masqueraded as chronic dacryocystitis. Head and neck surgeons should be aware of this disease entity when encountered with patients with epiphora and mass in the medial canthal area.