Proton Irradiation of Small Choroidal Malignant Melanomas

Gragoudas, Evangelos S.; Goitein, Michael; Koehler, Andreas; Verhey, Lynn; Tepper, Joel E.; Suit, Herman D.; Brockhurst, Robert J.; Constable, Ian

doi:10.1016/0002-9394(77)90133-7

Cited by 135 publications

(64 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…9,12,14,15 The radiation dose was 70 cobalt gray equivalents (CGE) delivered in 5 equal fractions over 7 to 10 days in most patients (94%); the remaining patients were treated with slightly higher or lower doses ranging from 50 to 100 CGE. (A CGE is the physical dose in gray multiplied by a relative biological effectiveness factor of 1.10.…”

Section: Methodsmentioning

confidence: 99%

Evidence-Based Estimates of Outcome in Patients Irradiated for Intraocular Melanoma

Gragoudas¹

2002

Arch Ophthalmol

177

103

View full text Add to dashboard Cite

Background: Melanoma of the eye is the only potentially fatal ocular malignancy in adults. Until radiation therapy gained wide acceptance in the 1980s, enucleation was the standard treatment for the tumor. Long-term results after proton beam irradiation are now available. Methods:We developed risk score equations to estimate probabilities of the 4 principal treatment outcomeslocal tumor recurrence, death from metastasis, retention of the treated eye, and vision loss-based on an analysis of 2069 patients treated with proton beam radiation for intraocular melanoma between July 10, 1975, and December 31, 1997. Median follow-up in surviving patients was 9.4 years.Results: Tumor regrowth occurred in 60 patients, and 95% of tumors (95% confidence interval, 93%-96%) were controlled locally at 15 years. Risk scores were developed for the other 3 outcomes studied. Overall, the treated eye was retained by 84% of patients (95% confidence interval, 80%-87%) at 15 years. The probabilities for vision loss (visual acuity worse than 20/200) ranged from 100% to 20% at 10 years and for death from tumor metastases from 95% to 35% at 15 years, depending on the risk group.Conclusions: High-dose radiation treatment was highly effective in achieving local control of intraocular melanomas. In most cases, the eye was salvaged, and functional vision was retained in many patients. The mortality rate was high in an identifiable subset of patients who may benefit from adjuvant therapies directed at microscopic liver metastases.

show abstract

Section: Methodsmentioning

confidence: 99%

Evidence-Based Estimates of Outcome in Patients Irradiated for Intraocular Melanoma

Gragoudas¹

2002

Arch Ophthalmol

177

103

View full text Add to dashboard Cite

show abstract

“…The patient outcome data revealed >99.7% local control at five years after treatment for small-and medium-sized tumors, retention of the eye in most cases and preservation of useful vision (Egger et al 2003, Gragoudas et al 1978, 1980, 1982, Munzenrider 2001, Munzenrider et al 1988, 1989, Seddon et al 1987, 1986, Suit et al 1977. After three decades of experience, the techniques used for treating uveal melanoma with proton therapy are fairly well understood (Gragoudas andMarie Lane 2005, Munzenrider 2001), and recent research efforts have focused on improving the dosimetric accuracy of these treatments (cf Newhauser 2005, Newhauser et al 2002a).…”

Section: Introductionmentioning

confidence: 99%

Monte Carlo calculations and measurements of absorbed dose per monitor unit for the treatment of uveal melanoma with proton therapy

Koch¹,

Newhauser²,

Titt³

et al. 2008

Phys. Med. Biol.

View full text Add to dashboard Cite

The treatment of uveal melanoma with proton radiotherapy has provided excellent clinical outcomes. However, contemporary treatment planning systems use simplistic dose algorithms that limit the accuracy of relative dose distributions. Further, absolute predictions of absorbed dose per monitor unit are not yet available in these systems. The purpose of this study was to determine if Monte Carlo methods could predict dose per monitor unit (D/MU) value at the center of a proton spread-out Bragg peak (SOBP) to within 1% on measured values for a variety of treatment fields relevant to ocular proton therapy. The MCNPX Monte Carlo transport code, in combination with realistic models for the ocular beam delivery apparatus and a water phantom, was used to calculate dose distributions and D/MU values, which were verified by the measurements. Measured proton beam data included central-axis depth dose profiles, relative cross-field profiles and absolute D/MU measurements under several combinations of beam penetration ranges and rangemodulation widths. The Monte Carlo method predicted D/MU values that agreed with measurement to within 1% and dose profiles that agreed with measurement to within 3% of peak dose or within 0.5 mm distance-to-agreement. Lastly, a demonstration of the clinical utility of this technique included calculations of dose distributions and D/MU values in a realistic model of the human eye. It is possible to predict D/MU values accurately for clinical relevant range-modulated proton beams for ocular therapy using the Monte Carlo method. It is thus feasible to use the Monte Carlo method as a routine absolute dose algorithm for ocular proton therapy.

show abstract

“…Radiotherapy offers the advantage of preservation of the eye, and may conserve a useful level of vision, depending on the size of the tumor and its location with respect to the optic disc and macula. Two major types of radiotherapy are available: radioactive plaques that are sutured on the sclera over the area of the tumor, [1][2][3][4] and external beam irradiation using charged particles such as protons [5][6][7][8] and helium ions. 9 These modalities, although effective in achieving local tumor control, may be associated with high rates of morbidity, particularly when the tumor is large or is located near the optic disc or fovea.…”

mentioning

confidence: 99%

A Randomized Controlled Trial of Varying Radiation Doses in the Treatment of Choroidal Melanoma

Gragoudas¹

2000

Arch Ophthalmol

Self Cite

149

View full text Add to dashboard Cite

To determine if a reduction in proton radiation dose from the standard dose of 70 cobalt gray equivalents (CGE) to 50 CGE would decrease radiation-induced complications, thereby improving visual prognosis, without compromising local tumor control for patients with uveal melanoma at high risk of these complications.Design: Randomized, double-masked clinical trial.Participants: A total of 188 patients with small or medium-sized choroidal melanomas (Ͻ15 mm in diameter and Ͻ5 mm in height) near the optic disc or macula (within 4 disc diameters of either structure).Methods: Patients were treated with proton beam therapy at doses of either 50 CGE or 70 CGE between October 1989 and July 1994, and followed up biannually through April 1998. Outcomes included visual acuity, radiation complications, melanoma recurrence, and metastasis.Results: Proportions of patients retaining visual acuity of at least 20/200 were similar in the 2 dose groups at 5 years after radiation (approximately 55%). Similar numbers of patients in each group experienced tumor regrowth (2 patients at 50 CGE vs 3 patients at 70 CGE; PϾ.99) and metastasis (7 patients at 50 CGE vs 8 patients at 70 CGE; P=.79). Five-year rates of radiation maculopathy also were similar (for both groups, approximately 75% for tumors within 1 disc diameter and 40% for tumors Ͼ1 disc diameter from the macula). Rates of radiation papillopathy were nonsignificantly decreased in the 50-CGE treatment group when tumors were located 1 disc diameter or less from the optic disc (P=.20). Patients treated with the lower dose also experienced significantly less visual field loss.Conclusions: This level of dose reduction did not result in a lesser degree of visual acuity loss. The lowerdose group did experience significantly less visual field loss. Local tumor recurrence and metastatic death rates were similar in both dose groups.

show abstract

Proton Irradiation of Small Choroidal Malignant Melanomas

Cited by 135 publications

References 11 publications

Evidence-Based Estimates of Outcome in Patients Irradiated for Intraocular Melanoma

Evidence-Based Estimates of Outcome in Patients Irradiated for Intraocular Melanoma

Monte Carlo calculations and measurements of absorbed dose per monitor unit for the treatment of uveal melanoma with proton therapy

A Randomized Controlled Trial of Varying Radiation Doses in the Treatment of Choroidal Melanoma

Contact Info

Product

Resources

About