Nearly half of choroidal melanomas progress to the metastatic stage at 15 years. The purpose of our study was to evaluate the prognostic value of tumour-height regression rate in medium-sized choroidal melanomas treated with iodine-125 brachytherapy. A retrospective cohort study was performed on 128 patients with medium-sized choroidal melanoma who were treated with iodine-125 brachytherapy. Tumour characteristics including tumour apical height at baseline and after irradiation, recurrence, metastasis and mortality were collected from patients’ records. Regression rate was defined in mm/month or in percentage of baseline apical height. Patients were statistically stratified in three groups of regression rate at 6 months using the Ward’s method and Euclidian distance (slow, medium and fast regression groups). Mean initial apical height was of 5.71±1.79 mm. At 6 months, the average regression rate was 0.02±0.12 mm/month in the slow group (n=60), 0.32±0.11 mm/month in the medium group (n=52) and 0.67±0.21 mm/month in the fast group (n=16). Cox regression analysis for the recurrence, metastasis and mortality rates according to the three groups did not show any statistically significant difference. Sensitivity analyses with the regression rates at 12 months showed similar associations. Exudative retinal detachment resolved with treatment at 5.9±4.0 months, and it was more common at presentation in the fast regression rate group. The regression rate at 6 and 12 months after iodine-125 brachytherapy is not associated with a higher metastatic rate in medium-sized choroidal melanoma.
aCentre universitaire d’ophtalmologie (CUO)
bCUO-Recherche et Axe médecine régénératrice
cPlateforme de recherche clinique, Centre de Recherche FRQS du CHU de Québec-Université Laval
eCentre de recherche sur le cancer
fCentre de recherche en organogénèse expérimentale, Faculté de Médecine, Université Laval, Québec, Canada
gDépartement de radio-oncologie, Centre François Baclesse, Caen
hUniv Rennes, INSERM, INRA, Institut NUMECAN (Nutrition Metabolisms and Cancer)
iService d’ophtalmologie, CHU de Rennes, Rennes, France
*Frédéric Mouriaux and Solange Landreville contributed equally to the writing of this article.
Correspondence to Frédéric Mouriaux, MD, PhD, Centre universitaire d’ophtalmologie, Hôpital du Saint-Sacrement, 1050 chemin Sainte-Foy, Quebec City, Québec G1S 4L8, Canada Tel: +1 418 682 7663; fax: +1 418 682 8000; e-mail: firstname.lastname@example.org
Received August 23, 2018
Accepted October 9, 2018