Adult alveolar rhabdomyosarcoma of the lacrimal sac

Lacrimal sac tumours are rare, but must be considered in the diagnosis of patients presenting with masses in the medial canthal region. We report a single case of lacrimal sac rhabdomyosarcoma in a 31-year-old man. The patient self-presented to the eye department with a 4-week history of discomfort, epiphora and a medial canthal mass. After no response to 1 week of oral antibiotics for a presumed diagnosis of dacryocystitis and the presence of firm mass extending above the medial canthal tendon, surgical exploration was carried out which revealed a lacrimal sac mass. Histologically this showed an alveolar rhabdomyosarcoma, which was confirmed on immunohistochemistry. After 4 rounds of chemotherapy and 50.4Gy of radical radiotherapy, the patient is well with no signs of further local or distant disease at 11-months follow-up and 20 months following initial diagnosis. To our knowledge, there are no previously reported adult cases of lacrimal sac alveolar rhabdomyosarcoma in the peer-reviewed literature. We want to highlight the unique diagnosis in this case as well as drawing attention to the possibility of malignancy in patients responding poorly to management when an initial diagnosis of dacryocystitis is made in the presence of a medial canthal mass.