Acute ocular toxicity and long-term visual outcome of primary and adjuvant hyperfractionated/accelerated radiation therapy of advanced paranasal sinus cancer employing proton irradiation

Abstract

Materials/Methods: Between 1991 and 2001, HART (4 MeV photons and 160 MeV protons) was used to treat 35 pts with advanced stage primary (n 32) or recurrent (n 3) malignant tumors of the paranasal sinuses for whom full neuroophtalmologic follow-up was obtained. Median age was 52 years (range, 18.5-74.4). Ten (29%) unresectable patients were treated with primary and 25 (71%) with adjuvant radiation therapy, respectively. Chemotherapy (CT) was administered to 13 (37%) patients, however, none received concurrent CT. Prospectively specified neuro-ophtalmologic follow-up consisted of pupillary examination, exophtalmometry, color vision and ocular pressure measurements, motility testing, as well as dilated fundus exam and Goldmann visual field. The median dose to the macroscopic gross tumor volume (GTV) was 69.6 CGE (range, 60-76.6 CGE, CGE proton Gy 1.1 RBE). Optical apparatus dose constraint was 2 CGE/day and 56 CGE total dose, respectively. If clinically indicated, the treating physician had the option to relax the optical dose constraints. Median GTV and clinical tumor volume were 90 cc (range, 5.4-318) and 251 cc (range, 40.9-636), respectively. Lens and retinal late complications were graded according to objective portion of the SOMA scale of the Late Effects of Normal Tissue (LENT) Scoring system. Other late ocular/visual symptoms were classified according to the NCI Common Toxicity Criteria (CTC) grading system. Disease-free Survival (DFS) and visual complication free survival (CFS) rate were calculated using KaplanMeier method. The studied risk factors for late visual complications included dose, gender, age, acute ocular toxicity, GTV volume, adjuvant chemotherapy and follow-up length. Statistical analysis was performed on SAS 8.1 software, using adequate methods including Student T-test and Log rank analysis. The median follow-up was 37.6 months (range, 4.4-122.8).