Adjuvant high-dose rate (HDR) brachytherapy for ocular tumours with orbital invasion

Abstract

Purpose : To evaluate adjuvant high-dose rate (HDR) brachytherapy effectiveness in local control, functional and cosmetic outcome in patients affected by ocular malignant tumours with orbital invasion.

Methods : A retrospective study was conducted in 9 patients affected by malignant eye cancer infiltrating the orbit , treated with surgical excision and subsequent (HDR) brachytherapy between 20012-2017. The primary tumour was uveal melanoma with extrascleral extension in 2 (22.2%) patients, conjunctival melanoma in 4 (44.4%), basal cell carcinoma in 1 (11.1%), squamous cell carcinoma in 1(11.1%) and sebaceous carcinoma in 1(11.1%).The surgical procedures consisted of modified enucleation in 4 patients (two affected by uveal melanoma with extrascleral extension and two affected by conjunctival melanoma with globe invasion) and surgical excision of the primary tumour and orbital infiltration in the remaining patients.
Within one month from the surgery each underwent adjuvant interstitial high doses brachytherapy with 192Ir. A target dose of 3400 cGy (range, 3000-3400 cGy) was delivered in 10-12 twice-daily fractions (range, 250-340 cGy per fraction) over 5-6 consecutive days. Data analysis included local tumor control and metastatic rate, side effects, functional and aesthetic results.

Results : in all patients treatment was well tolerated, there was no orbital recurrence at a median follow-up of 12,6 months (range 3-28 months). One patient died of metastatic disease. No significant side effect was observed, functional and cosmetic outcomes were optimal.

Conclusions : postoperative high-dose-rate brachytherapy resulted in an excellent disease control and cosmesis without significant acute or late side effects. It rappresents an alternative treatment to external beam radiation for eye with orbit invasion.

This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.