Abstract
Purpose: :
Epiphora and occlusion of the nasolacrimal ducts as complication of radioiodine therapy (RAI) for thyroid carcinoma are considered particularly rare. Few recent articles described this association. However , the real incidence seems to be higher because the incidence of thyroid cancer in United States is increasing: from 3.6 to 8.7 per 100.000 in the last 30 years- a 2.4 fold increase.Our objective is report the nasolacrimal drainage system obstruction associated with RAI in a Brazilian series patients.
Methods: :
Retrospective analysis of patients with history of thyroid carcinoma who undergone radioactive iodine I-131 therapy and referred to lacrimal surgery.
Results: :
17 patients with thyroid cancer treated with tyroidectomy and radioactive iodine I-131 therapy presented symptomatic nasolacrimal duct obstruction after 13.2 months following cancer treatment. 11 patients presented bilateral epiphora, 8 had lacrimal sac mucocele. All subjects underwent dacryocistorhinostomy. 59% of patients had less than or equal to 49 years (range, 30 to 80 years).The mean cumulative dose of radioiodine was 571mCi (range: 200-1200 mCi) , higher dose were applied to metastatic cases.It was also observed dilation of lacrimal sac and increased intraoperative bleeding in 3 younger patients. Nasal obstruction symptoms and increased salivary glands also were present in 53% of patients.Complete epiphora and dacryocistitis resolution after surgery occurred in 82.4% , and partial in 17.6% (3 patients who still presented unilateral relapse after correction of bilateral obstruction). Mean follow-up was 6 months (range:2 -24 months).
Conclusions: :
There are no previous description of nasolacrimal drainage obstruction after RAI in a Brazilian population. Cumulative high dose of radioidine, nasal and salivary gland disfunction are associated with this condition. We observed a great percentage of younger patients presenting dacryocistitis when compared to the idiopathic dacrioestenosis.Radioactive iodine uptake by nasolacrimal duct mucosa with subsequent inflammation, edema and fibrosis seems to have a relationship to lacrimal duct obstruction. Knowledge of this complication is important for the study and proper management of these patients.
Keywords: radiation therapy • clinical (human) or epidemiologic studies: risk factor assessment • clinical (human) or epidemiologic studies: outcomes/complications