Treatment outcomes after definitive radio(chemo)therapy for 17 lacrimal sac squamous cell carcinoma

Abstract

Objectives: Tumors of the lacrimal sac are rare and life-threatening. Because of their rarity, no extensive clinical data on their management and prognosis exist. We investigated the application of definitive radiation therapy and its outcome in patients with lacrimal sac squamous cell carcinoma (LSSCC). Methods: We retrospectively studied 17 patients with LSSCC at a single institution between 2003 and 2017. All the patients were treated with definitive radiotherapy, and 11 patients were delivered with cisplatin-based chemotherapy. The patients’ clinical records were reviewed for symptoms, pathological types, the volume and dosimetry of the tumors and their adjacent structures, radiation coverage of lymph node drainage areas, treatment outcomes, and complications from definitive radiotherapy. Results: Median follow-up was 38.9 months, and age at diagnosis was 48 years.The 2-year and 5-year overall survival, progression-free survival, locoregional control, and disease metastasis-free survival rates were 94.1 and 84.7%, 88.2 and 73.5%, 93.8%, 94.1, and 78.4%, respectively. A total dose of 6600–7000 cGy was prescribed to the tumor. Levels Ⅰb, Ⅶa, Ⅷ, and Ⅸ were covered with the clinical target volume regardless of lymph involvement. Acute Grade 3 radiation dermatitis occurred in seven patients (17.6%), but no acute Grade 4 or Grade 5 toxicity of any type occurred. Seven (41.2%, 7/17) of the treated eyes had moderated vision impairments; 17.6% (3/17) of patients developed cataracts, and glaucoma and radiation retinopathy were found in 5.9% (1/17) of patients. Conclusions: Definitive radiotherapy could be a treatment option for those who refuse surgery or have unresectable LSSCC. Advances in knowledge: Radiation alone is a treatment option for LSSCC.