Comparison of episcleral plaque and proton beam radiation therapy for the treatment of choroidal melanoma

doi:10.1016/S0161-6420(99)90456-6

Ophthalmology

Volume 106, Issue 8, 1 August 1999, Pages 1579-1587

https://doi.org/10.1016/S0161-6420(99)90456-6 Get rights and content

Abstract

Purpose

To compare the efficacy of iodine-125 (¹²⁵I) and ruthenium-106 (¹⁰⁶Ru) episcleral plaque radiation therapy and proton beam radiation therapy (PBRT) in the treatment of choroidal melanoma.

Design

A retrospective, nonrandomized comparative study.

Methods

Charts of patients treated with ¹²⁵I, ¹⁰⁶Ru, and PBRT for choroidal melanoma between January 1988 and June 1996 at St. Bartholomew’s Hospital and Moorfields Eye Hospitals were reviewed.

Main outcome measure

Local control of choroidal melanomas after ¹²⁵I, ¹⁰⁶Ru, or PBRT.

Results

A total of 597 patients were identified (¹²⁵I = 190, ¹⁰⁶Ru = 140, PBRT = 267). Patients treated with ¹⁰⁶Ru had a significantly greater risk of local tumor recurrence than did patients treated with either ¹²⁵I (P = 0.0133; confidence interval [CI], 1.26–7.02; risk ratio, 2.97) or PBRT (P = 0.0097; CI, 1.30–6.66; risk ratio, 2.94). A stepwise Cox proportional hazard model found maximal basal diameter to be a significant covariate (P = 0.0033).

Conclusion

Patients treated with ¹⁰⁶Ru had a significantly greater risk of local tumor recurrence than did those patients treated with either ¹²⁵I or PBRT.

Section snippets

Patients and methods

A retrospective chart review of patients treated with ¹²⁵I, ¹⁰⁶Ru, and PBRT for choroidal melanoma from January 1988 through June 1996 at St. Bartholomew’s Hospital and Moorfields Eye Hospital, London, England, was performed. The following clinical data were extracted from the patients’ medical records: treatment type, age, gender, affected eye, tumor location, tumor height and maximal basal diameter, presence of subretinal fluid, pretreatment visual acuity, visual acuity at last examination,

Results

Clinical features of the patients and tumors are summarized in Table 1. There were 597 patients with unilateral choroidal melanoma identified. The mean age at the time of treatment was 57.1 years (range, 13–87 years; standard deviation [SD], 13.3 years). There were 314 females and 283 males. The right eye was affected in 273 patients, and the left eye was affected in 324 patients. The mean tumor height was 5.8 mm (range, 1.4–15.4 mm; SD, 2.9 mm). The mean tumor maximal basal diameter was 10.8

Discussion

The optimum form of radiation therapy for the treatment of choroidal melanoma has not yet been discovered. Our study does not solve this dilemma. We found that patients treated with ¹⁰⁶Ru episcleral plaque radiation therapy had a significantly greater risk of local tumor recurrence than did those patients treated with ¹²⁵I (P = 0.0133; CI, 1.26–7.02; RR, 2.968) and PBRT (P = 0.0097; CI, 1.30–6.66; RR, 2.941). We were surprised by our findings. Patients treated with ¹⁰⁶Ru had tumors with smaller