A Five-Year Study of Slotted Eye Plaque Radiation Therapy for Choroidal Melanoma: Near, Touching, or Surrounding the Optic Nerve

Comparing efficacy of charged-particle therapy with brachytherapy in treatment of uveal melanoma

BACKGROUND

Uveal melanoma (UM) is the most common primary ocular tumour in adults. The most used eye-preserving treatments are charged-particle therapy (CPT) and brachytherapy. We performed a systematic review and meta-analysis to compare efficacies and complications of these two radiotherapies.

METHODS

We searched EMBASE, PubMed, MEDLINE, and the Cochrane Library from January 2012 to December 2022. Two independent reviewers identified controlled studies comparing outcomes of CPT versus brachytherapy. Case series that utilize either treatment modality were also reviewed.

RESULTS

One hundred fifty studies met the eligibility criteria, including 2 randomized control trials, 5 controlled cohort studies, and 143 case series studies. We found significant reduction in local recurrence rate among patients treated with CPT compared to brachytherapy (Odds ratio[OR] 0.38, 95% Confidence interval [CI] 0.24-0.60, p < 0.01). Analysis also showed a trend of increased risks of secondary glaucoma after CPT. No statistically significant differences were found in analyzing risks of mortality, enucleation, and cataract.

CONCLUSIONS

Our study suggested no difference in mortality, enucleation rate and cataract formation rate comparing the two treatments. Lower local recurrence rate and possibly higher secondary glaucoma incidence was noted among patients treated with CPT. Nevertheless, the overall level of evidence is limited, and further high-quality studies are necessary to provide a more definitive conclusion.

Recent approaches for the treatment of uveal melanoma: Opportunities and challenges

Uveal melanoma (UM) is the most prevalent primary intraocular cancer in adult population. Primary methods for treatment of UM involves surgery Proton Beam Therapy (PBT), Plaque Brachytherapy, phototherapy, and Charged Particle Radiation Therapy (CPT). It has been found that approximately 50 % of patients diagnosed with UM ultimately experience development of metastatic disease. Furthermore, it has been identified that majority of the patient experience metastasis in liver with a prevalence of 95 %. Management of metastatic UM (MUM) involves various therapeutic modalities, including systemic chemotherapy, molecular targeted therapy, immunotherapy and liver directed interventions. We outline gene mutation in UM and addresses various treatment modalities, including molecular targeted therapy, miRNA-based therapy, and immunotherapy. Additionally, inclusion of ongoing clinical trials aimed at developing novel therapeutic options for management of UM are also mentioned.

Laser treatment for choroidal melanoma: Current concepts

Laser treatment has offered a relatively nonsurgical alternative for eye, life, and vision-sparing treatment of malignant melanoma of the choroid. Historically, the most commonly used forms of lasers were xenon-arc, argon laser, krypton laser, and the more recent transpupillary thermotherapy (TTT) and photodynamic therapy (PDT). Melanomas selected for laser treatment tend to be smaller and visibly accessible, which means these tumors are usually located in the posterior choroid. Laser treatments have been associated with both local tumor destruction and side effects. Unlike radiation therapy, laser treatment has been commonly associated with retinal traction, hemorrhage, chorioretinal neovascularization, and extra scleral tumor extension, as well as higher rates of local treatment failure. In addition, however, laser-treatment has been successfully used to treat tumor-related retinal detachments, radiation retinopathy, and neovascular glaucoma. We review the world's experience of ophthalmic laser treatment for choroidal melanoma, offer safety and efficacy guidelines, as well as a comparison of laser treatment to radiation therapy outcomes.

Outcomes following Notched Ruthenium-106 Plaque Brachytherapy for Juxtapapillary Choroidal Melanomas

Purpose

This study aimed to evaluate the outcomes of juxtapapillary choroidal melanomas treated with notched ruthenium-106 plaques.

Methods

Juxtapapillary choroidal melanomas (tumours within 2 disc diameters from the optic disc) treated with notched ruthenium-106 plaques (Eckert & Ziegler, BEBIG, Berlin, Germany) at the Scottish Ocular Oncology Service between 2009 and 2015 were retrospectively reviewed. The data were analysed with respect to various outcome measures including recurrence, complications, vision, and eye preservation.

Results

We reviewed 40 patients with a median tumour diameter of 8.4 mm (range 5-17 mm) and a median thickness of 2.5 mm (range 1.1-6 mm). AJCC tumour category distribution was 62.5% T1, 32.5% T2, and 5% T3 tumours. The mean presenting vision was 0.3 logMAR, and the mean final vision was 0.7 logMAR, with 62.5% retaining >1.0 logMAR and 50% retaining >0.3 logMAR at the final follow-up. The median follow-up was 51 months (14-100 months). Over the maximum follow-up time, 13 tumours (32.5%) recurred. Six of these were treated with salvage proton beam therapy (PBT), 2 with transpupillary thermotherapy followed by PBT, and 5 with enucleation. The final eye retention rate was 87.5%. Complications included maculopathy (10%), retinal detachment (5%), neovascular glaucoma (2.5%), and diplopia (2.5%). The observed risk of recurrence over 5 years was 31% (95% CI: 14.1%, 47.8%), and the risk of enucleation over 5 years was 11.5% (95% CI: 0.9%, 21.8%).

Conclusion

Juxtapapillary choroidal melanomas treated with notched ruthenium plaques have a high recurrence rate and frequently need salvage treatment with PBT for tumour control. This has led to a change in our practice toward offering PBT as the first-line treatment for these patients.

Optic disc cupping after circumpapillary Pd-103 slotted plaque radiation therapy

OBJECTIVE

To investigate vascular and morphologic optic disc changes after slotted plaque radiation therapy for choroidal melanoma involving the optic disc.

DESIGN

Retrospective cross-sectional study.

PARTICIPANTS

Thirty-nine patients with choroidal melanoma involving the optic nerve.

METHODS

Each melanoma was treated with palladium-103 slotted plaque brachytherapy (incorporating and/or surrounding the optic nerve sheath) between 2005 and 2019. Imaging of the optic nerve before and after radiation allowed for documentation and evaluation of optic nerve pallor and cup-to-disc ratio (CDR) changes. Optical coherence tomography (OCT) CDR measurements and intraocular pressure (IOP) were recorded pretreatment and at follow-up. Of these patients, 22 also had OCT angiography (OCT-A) images with sufficient quality for evaluation of blood vessel density and length. Differences in cup-to-disc measurements were correlated with changes in OCT-A-measured vessel density and length.

RESULTS

Following slotted plaque radiation therapy, there was no significant increase in IOP or optic nerve pallor. OCT and colour photography revealed significant increases (both p < 0.001) in CDR from pretreatment to the last follow-up. Increased CDRs on OCT were significantly correlated to OCT-A-measured change in vessel length (p = 0.027). Similarly, increased CDR ratios on fundus photography were significantly correlated with OCT-A-measured change in vessel density (p = 0.043) and length (p = 0.019).

CONCLUSION

Fundus photography and OCT measurements revealed increased optic disc cupping following slotted plaque radiation therapy. Cupping was associated with OCT-A evidence of synchronous progressive peripapillary vascular occlusion and attenuation. Therefore, slotted plaque radiation-induced peripapillary and papillary ischemia was associated with increased CDR ratios and optic disc cupping.

Local tumor control and treatment related toxicity after plaque brachytherapy for uveal melanoma: A systematic review and a data pooled analysis

Uveal melanoma (UM) represents the most common primary intraocular tumor, and nowadays eye plaque brachytherapy (EPB) is the most frequently used visual acuity preservation treatment option for small to medium sized UMs. The excellent local tumor control (LTC) rate achieved by EPB may be associated with severe complications and adverse events. Several dosimetric and clinical risk factors for the development of EPB-related ocular morbidity can be identified. However, morbidity predictive models specifically developed for EPB are still scarce. PRISMA methodology was used for the present systematic review of articles indexed in PubMed in the last sixteen years on EPB treatment of UM which aims at determining the major factors affecting local tumor control and ocular morbidities. To our knowledge, for the first time in EPB field, local tumor control probability (TCP) and normal tissue complication probability (NTCP) modelling on pooled clinical outcomes were performed. The analyzed literature (103 studies including 21,263 UM patients) pointed out that Ru-106 EPB provided high local control outcomes while minimizing radiation induced complications. The use of treatment planning systems (TPS) was the most influencing factor for EPB outcomes such as metastasis occurrence, enucleation, and disease specific survival, irrespective of radioactive implant type. TCP and NTCP parameters were successfully extracted for 5-year LTC, cataract and optic neuropathy. In future studies, more consistent recordings of ocular morbidities along with accurate estimation of doses through routine use of TPS are needed to expand and improve the robustness of toxicity risk prediction in EPB.

Clinical outcomes and secondary glaucoma after gamma-knife radiosurgery and Ruthenium-106 brachytherapy for uveal melanoma: a single institution experience

We retrospectively analyzed data from records of 48 patients (48 eyes) treated with gamma-knife (n = 18) or Ruthenium-106 brachytherapy (n = 30) for uveal melanoma, in our Ocular Oncology Unit between December 2013 and September 2019, with the aim to evaluate treatment outcomes, and incidence and risk factors for secondary glaucoma. Patients demographics and tumor characteristics at diagnosis were recorded. Follow-up data were collected regarding local tumor control, treatment complications, enucleation need, metastases occurrence and survival status. The median follow-up period was 33.7 months in the gamma-knife group and 26.2 months in the brachytherapy group. The mean tumor thickness, the largest basal diameter and the tumor volume were significantly higher in the gamma-knife group than in the brachytherapy group. The local tumor control rate was 100% in the brachytherapy group and 77.8% in the gamma-knife group. In the gamma-knife group, six patients were enucleated, no patient treated with brachytherapy underwent enucleation. The overall survival rate was 96.7% in the brachytherapy group and 94.44% in the gamma-knife group. Secondary glaucoma occurred in 10 patients after gamma-knife and in one patient after brachytherapy: it should be emphasized that larger lesions were treated with gamma-knife, whereas smaller tumors were selected for brachytherapy. We found a significative correlation of tumor thickness (P value = 0.043) and volume (P value = 0.040) with secondary glaucoma occurrence after gamma-knife treatment. Moreover, secondary glaucoma significantly correlated with radiation retinopathy in the gamma-knife group (P value = 0.009). This study shows preliminary clinical results that could be useful for further studies with more patients and longer follow-up.

Long-term outcomes after enucleation or plaque brachytherapy of choroidal melanomas touching the optic disc

PURPOSE

To investigate local and systemic outcomes after enucleation, brachytherapy with ruthenium-106, iodine-125, notched and non-notched plaques and transpupillary thermotherapy (TTT) of choroidal melanomas touching the optic disc.

METHODS AND MATERIALS

All patients treated for choroidal melanoma touching the optic disc at St. Erik Eye Hospital, Stockholm, Sweden between 1984 and 2015 (n = 165) were included. Retrospective clinicopathological data was collected and 3D dosimetry performed.

RESULTS

Ninety-five patients (58 %) had been treated with ruthenium-106 brachytherapy, 21 (13 %) with iodine-125 brachytherapy and 49 (30 %) with enucleation. Median follow-up was 12.3 years. In simulations, some tumor areas were underdosed with non-notched plaques. Fifty of 116 patients (43 %) underwent a secondary brachytherapy (n = 5), enucleation (n = 29) or TTT (n = 16). In multivariate Cox Regressions, there were no significant differences in the risk for tumor progression or lack of regression between radioisotopes and notched and non-notched plaques. Adding TTT did not reduce the risk for a second treatment. The number of clock hours of circumpapillary tumor growth did not correlate to the risk for treatment failure or mortality. There were no significant differences in melanoma-related mortality for any treatment including enucleation. Kaplan-Meier disease-specific survival was 77 % at 5 years, 72 % at 10 years and 67 % at 20 years.

CONCLUSION

Plaque brachytherapy of choroidal melanomas touching the optic disc entails a two to threefold increased risk for treatment failure. This risk is similar between radioisotopes, notched and non-notched plaque designs and if TTT is used or not. The high rate of treatment failure does not lead to increased mortality.

Optic disc dose reduction in ocular brachytherapy using 125 I notched COMS plaques: A simulation study based on current clinical practice

PURPOSE

Although notched Collaborative Ocular Melanoma Study (COMS) plaques have been widely used, optic disc dose reduction by notched COMS plaques has not been discussed in the literature. Therefore, this study investigated optic disc dose reduction in ocular brachytherapy using ¹²⁵ I notched COMS plaques in comparison with optic disc dose for ¹²⁵ I standard COMS plaques.

METHODS

For this simulation study, an in-house brachytherapy dose calculation program was developed using MATLAB software by incorporating the American Association of Physicists in Medicine Task Group-43 Update (AAPM TG-43U1) dosimetry formalism with a line source approximation in a homogeneous water medium and COMS seed coordinates in the AAPM TG 129. Using this program, optic disc doses for standard COMS plaques (from 12 to 22 mm in diameter in 2 mm increments) and notched COMS plaques with one seed removed (Case #1, from 12 to 22 mm) and with two seeds removed (Case #2, from 14 to 22 mm) were calculated as a function of tumor margin-to-optic disc distance (DT) for various tumor basal dimensions (BDs) for prescription depths from 1 to 10 mm in 1 mm intervals. A dose of 85 Gy for an irradiation time of 168 h was prescribed to each prescription depth. Then absolute and relative optic disc dose reduction by notched COMS plaques (Cases #1 and #2) was calculated for all prescription depths.

RESULTS

Optic disc dose reduction by notched COMS plaques (Cases #1 and #2) had five unique trends related to maximum optic disc dose reduction and corresponding optimal DT for each BD in each plaque. It increased with increasing prescription depth.

CONCLUSIONS

The results presented in this study would enable the clinician to choose an adequate plaque type among standard and notched ¹²⁵ I COMS plaques and a prescription depth to minimize optic disc dose.

Glaucomagenesis following ionizing radiation exposure

Glaucoma is a group of optic neuropathies causing optic nerve damage and visual field defects, and is one of the leading causes of blindness. Nearly a century has passed since the first report of glaucoma manifested following ionizing radiation therapy of cancers. Nevertheless, associations between glaucoma and radiation exposures, a dose response relationship, and the mechanistic underpinnings remain incompletely understood. Here we review the current knowledge on manifestations and mechanisms of radiogenic glaucoma. There is some evidence that neovascular glaucoma is manifest relatively quickly, within a few years after high-dose and high dose-rate radiotherapeutic exposure, but little evidence of excess risks of glaucoma after exposure to much lower doses or dose rates. As such, glaucoma appears to have some of the characteristics of a tissue reaction effect, with a threshold of at least 5 Gy but possibly much higher.

Brachytherapy for patients with uveal melanoma: historical perspectives and future treatment directions

Surgical management with enucleation was the primary treatment for uveal melanoma (UM) for over 100 years. The Collaborative Ocular Melanoma Study confirmed in 2001 that globe-preserving episcleral brachytherapy for UM was safe and effective, demonstrating no survival difference with enucleation. Today, brachytherapy is the most common form of radiotherapy for UM. We review the history of brachytherapy in the treatment of UM and the evolution of the procedure to incorporate fine-needle-aspiration biopsy techniques with DNA-and RNA-based genetic prognostic testing.

Plaque brachytherapy for posterior uveal melanoma in 2018: improved techniques and expanded indications

PURPOSE OF REVIEW

Plaque brachytherapy remains the dominant globe-sparing therapy of uveal melanoma. This report highlights recent advances, which have expanded plaque brachytherapy's uses as well as improved the surgical technique.

RECENT FINDINGS

Plaque brachytherapy is effective for tumors that may previously have demanded enucleation. Plaque brachytherapy can be used to control large melanomas as well as melanomas touching the optic nerve. Improvements in planning and design have made plaque therapy simpler for the surgical operator and may reduce collateral radiation damage to normal ocular structures. The COMS implies a required dose of 85 Gy to the tumor apex for treatment of uveal melanoma. However, multiple reports indicate that lower doses may be equally effective for tumor control while reducing radiation dose to uninvolved structures. Vitreoretinal surgeons can be called upon safely to treat long-term side effects of radiation or tumor death such as intractable vitreous hemorrhage or inflammation. Further, vitreoretinal surgeons have employed tumor endoresection as primary local tumor control or in combination with plaque brachytherapy.

SUMMARY

Plaque brachytherapy for uveal melanoma remains highly effective for local tumor control and prevention of metastasis. Indications for plaque brachytherapy have expanded, and the technique has improved.

A 12-Year Study of Slotted Palladium-103 Plaque Radiation Therapy for Choroidal Melanoma: Near, Touching, or Surrounding the Optic Nerve

PURPOSE

To present our 12-year experience with low-energy-photon, slotted eye plaque radiation therapy.

DESIGN

Retrospective interventional case series.

METHODS

Setting: The New York Eye Cancer Center.

STUDY POPULATION

Fifty-two consecutive patients with uveal melanomas near, touching, or surrounding the optic disc.

INTERVENTION

Slotted eye plaque radiation therapy.

MAIN OUTCOME MEASURES

Change in visual acuity, local tumor control, radiation side effects, eye salvage, and systemic metastases.

RESULTS

Tumors were peripapillary within 1.5 mm of the optic disc (n = 8, 15%), juxtapapillary touching ≤180 degrees (n = 23, 44%), or circumpapillary >180 degrees and encircling the disc (n = 21, 41%). Mean follow-up was 47 months (median 34 months, range 6-146 months). Radiation induced a mean 41.2% reduction in tumor thickness. Life table analysis showed that 69% of patients retained their visual acuities ≥ 20/40 and had a vision loss-free survival 84 months after treatment. Also, 90% of patients retained their visual acuity between 20/50 and 20/200 and had a vision loss-free survival 36 months after treatment. Slotted plaque brachytherapy was associated with 4% secondary cataract, 11% neovascular glaucoma, and no dry eye or eyelash loss. Local tumor control (no recurrence) was achieved in 98.1% of patients. Life table analysis showed an overall enucleation-free survival of 93% and metastasis-free survival of 94%.

CONCLUSIONS

Slotted plaque radiation therapy provided a normalized plaque-tumor position, such that the entire choroidal melanoma plus a 2- to 3-mm free margin of normal-appearing tissue was included in the targeted zone. At 12 years, slotted plaque radiation therapy resulted in high rates of local tumor control and vision and eye retention.

Efficacy and Safety of Low-Dose Iodine Plaque Brachytherapy for Juxtapapillary Choroidal Melanoma

PURPOSE

To evaluate low- vs high-dose plaque brachytherapy for juxtapapillary choroidal melanoma.

DESIGN

Retrospective interventional case series.

METHODS

Setting: Single institution.

STUDY POPULATION

Forty-seven patients with juxtapapillary choroidal melanoma.

INTERVENTION

Iodine-125 plaque brachytherapy. Eyes were divided into apex low-dose (LD) and high-dose (HD) groups (≤ or > median apex dose 84.35 Gy). Main outcome measures were time to distant failure, local failure, death, enucleation, radiation retinopathy, optic neuropathy, and best-corrected visual acuity (BCVA).

RESULTS

Freedom from distant failure rates were 96% and 95% in apex LD and HD groups at 5 years and 77% and 95% at 10 years, respectively (P = .84). Freedom from local failure rates were 90% in the apex LD group vs 89% in the HD group at 5 and 10 years (P = .96). Apex LD and HD groups did not differ for time to death or enucleation. Five- and 10-year freedom from radiation retinopathy and optic neuropathy rates were higher in the apex LD than HD group. Loss of ≥3 BCVA lines, final BCVA 20/40 or better, and final BCVA 20/200 or worse were more favorable in the 5 mm LD compared to HD group. Visual acuity outcomes did not differ between apex LD and HD groups.

CONCLUSIONS

Low-dose iodine-125 plaque brachytherapy (67.5-81 Gy at tumor apex) provides safe and effective tumor control for juxtapapillary choroidal melanoma and may be associated with reduced radiation toxicity. Larger trials are needed to determine the optimal therapeutic dose for juxtapapillary choroidal melanoma.

Choroidal melanoma: A short review with an Indian perspective

Choroidal melanoma (CM), the most common intraocular tumor in adults, is still a rarity in Asia. Having a high propensity for metastasis with a poor survival, recognizing it early is essential. Although it has typical clinical features, there are instances of simulating lesions. Fine-needle aspiration biopsy can be a valuable tool not only to confirm our clinical suspicion but also aid in prognosticating it. From days of histopathological prognostic markers, we are moving on to genetic markers which are reliably providing insights, helping us in providing a better care for our patients. Eye preservation has taken an all new important meaning in CM with many centers opting for different modalities of radiation. Herein, we try to provide a short synopsis of CM looking into its epidemiology, clinical features, diagnosis, and management. We also look briefly into the role of fine-needle biopsy in managing CM. Being a tertiary referral ocular center in India, we do come across CM; we have shared the preliminary reports of our analysis of managing CM over a 9-year period.

Juxtapapillary and circumpapillary choroidal melanoma: globe-sparing treatment outcomes with iodine-125 notched plaque brachytherapy

PURPOSE

Managing juxtapapillary and circumpapillary choroidal melanoma with brachytherapy is challenging because of technical complications with accurate plaque placement and high radiation toxicity given tumor proximity to the optic nerve. We evaluated our center's experience using ultrasound-guided, Iodine (I)-125 notched plaque brachytherapy for treating choroidal melanoma contiguous with (juxtapapillary) and at least partially surrounding the optic disc (circumpapillary).

METHODS

All cases of choroidal melanoma treated with I-125 notched plaque brachytherapy at our center from September 2003-December 2013 were retrospectively reviewed. Only patients with ≥18 months of follow-up who had lesions contiguous with the optic disc (0 mm of separation) were included. The tumor apex prescription dose was 85 Gy. Outcomes evaluated included local control, distant metastasis-free survival (DMFS), cancer-specific survival (CSS), overall survival (OS), visual acuity, and radiation toxicity.

RESULTS

Thirty-four patients were included with a median follow-up of 44.1 months (range 18.2-129.0). AJCC T-category was T1 in 58.8%, T2 in 26.5%, and T3 in 14.7%. Median circumferential optic disc involvement was 50% (range 10%-100%). Eye retention was achieved in 94.1%. Actuarial 2- and 4-year rates of local recurrence were 3.1% and 7.6%, DMFS were 97.0% and 88.5%, CSS were 97.0% and 92.8%, and OS were 97.0% and 88.9%, respectively. In addition, 23.5% had visual acuity ≥20/200 at last follow-up.

CONCLUSIONS

I-125 notched plaque brachytherapy provides high eye preservation rates with acceptable longer-term post-treatment visual outcomes. Based on our experience, choroidal melanoma directly contiguous with and partially encasing the optic disc may be effectively treated with this technique.

Transscleral resection without hypotensive anaesthesia vs iodine-125 plaque brachytherapy in the treatment of choroidal melanoma

AimsThe aim of this study was to compare transscleral resection technique performed without hypotensive anaesthesia (TSRWH) with iodine-125 brachytherapy (IBT) in the treatment of choroidal melanoma.Patients and methodsThis was a retrospective surgical cohort study. Nineteen eyes treated with TSRWH were matched with 53 eyes treated with IBT according to: tumour size, distance to fovea, distance to optic nerve, and follow-up time. Best-corrected visual acuity (BCVA), local recurrence, secondary enucleation, metastasis, overall and specific survival, and complications were evaluated.ResultsPatients treated with TSRWH had significantly better BCVA than those treated with IBT. The local recurrence risk was significantly higher when ciliary body was involved (HR=11.4, 95% CI 2.24-49.7, P=0.04). Metastatic disease was observed in 14 of 53 patients (26.4%) in the IBT group vs 3 patients (15.8%) in the TSRWH group (P=0.531). Multivariate analysis showed that iris involvement (HR=16.0, 95% CI 4.2-170.2, P=0.033) and large tumour (HR=2.3, 95% CI 1.2-4.8, P=0.04) increased the probability of metastasis. During follow-up, six patients (11.3%) in IBT group died vs two (10.5%) in the TSRWH group (P≥0.999). Nine patients required secondary enucleation: 5 (9.4%) in the IBT group vs 4 (21.1%) in the TSRWH group (P=0.231). The most common complications in IBT group were radiation-induced retinopathy (45.3%), neovascular glaucoma (28.3%), and macular oedema (24.5%), whereas rhegmatogenous retinal detachment (21.1%), ocular hypertension (21.1%), and submacular haemorrhage (15.8%) were the most frequent complications after TSRWH.ConclusionTSRWH is a technically challenging procedure. However, when performed successfully, this technique achieves better preservation of visual acuity than IBT and without the limitations inherent in hypotensive anaesthesia.

Local Recurrence Significantly Increases the Risk of Metastatic Uveal Melanoma

PURPOSE

To assess of the effect of local recurrence of uveal melanoma on metastasis using a multicenter international tumor registry.

DESIGN

Retrospective study using an online tumor registry.

PARTICIPANTS

Patients with uveal melanoma diagnosed between 2001 and 2011.

METHODS

A committee was formed to create uveal melanoma patient-specific data fields. Ten subspecialty ophthalmic oncology centers from 4 continents shared data. Patient selection criteria included diagnosis of uveal melanoma and adequate records to allow tumor staging by American Joint Committee on Cancer (AJCC) criteria and follow-up for metastatic melanoma.

MAIN OUTCOME MEASURES

Local tumor recurrence and metastatic uveal melanoma.

RESULTS

Of 3809 total entries, 3217 patients with ciliary body and choroidal (CBC) melanoma and 160 with iris melanoma were evaluated. There was a median follow-up of 3.7 years (95% confidence interval [CI], 3.5-3.8). One hundred fifty-two patients (4.7%) with CBC melanoma experienced local recurrence, with a cumulative incidence of 11%. Kaplan-Meier point estimates for remaining free of local recurrence were 99% (95% CI, 99-99) at 1 year, 93% (95% CI, 92-94) at 5 years, and 89% (95% CI, 86-91) at 10 years. Five- and 10-year metastasis-free Kaplan-Meier estimates for the recurrence-free group were 87% (95% CI, 86-89) and 82% (95% CI, 79-84), and those for the local recurrence group were 71% (95% CI, 62-78) and 62% (95% CI, 49-72). The difference between these 2 groups was statistically significant (P < 0.001). Furthermore, local tumor recurrence increased the risk of metastasis by a hazard ratio (HR) of 6.28 (95% CI, 4.4-8.9; P < 0.001). Local recurrence was detected up to 9.8 years after treatment. Extrascleral extension also was associated with local recurrence (HR, 3.2; 95% CI, 1.5-6.7; P = 0.003), but higher AJCC T-size category was not (P = 0.63). Five patients (n = 5/161 [3.1%]) with iris melanoma demonstrated local recurrence and 1 metastasized.

CONCLUSIONS

International multicenter data sharing was used to evaluate the effect of local tumor recurrence on metastatic rate. In that local tumor recurrence was associated with a significantly higher risk of systemic metastasis, effective initial treatment and long-term surveillance of treated uveal melanoma patients is necessary.

Proton beam therapy of parapapillary choroidal melanoma

PURPOSE

To analyze the functional outcome with regard to the development of visual acuity and radiation-induced optic neuropathy of patients with parapapillary choroidal melanoma treated with proton beam therapy.

DESIGN

Clinical case series, retrospective study.

METHODS

We evaluated 147 consecutive patients with parapapillary choroidal melanoma who received proton beam therapy as primary tumor treatment at the Helmholtz Center in Berlin from 1998 to 2005. A cumulative dose of 60 Cobalt Gray Equivalents (CGE) was delivered to the tumor and the optic disc received a minimum of 50 CGE. Kaplan-Meier analysis was used to assess ocular outcome and survival rates. For trend analysis of functional development, Wilcoxon-Mann-Whitney U test was used to compare the medians of 2 groups and Kruskal-Wallis test was used in the case of more than 2 groups.

RESULTS

The mean follow-up time was 6.5 years (range 0.3-11.7 years). The most common side effects were radiation-induced optic neuropathy, retinopathy, and cataract. The median visual acuity before and within the first year after therapy was 0.4 logMAR (20/50), lapsing to 1.3 logMAR (20/400) after 3 years and 1.4 logMAR (20/500) after 5 years. During follow-up, no light perception developed in 17 cases (11.6%), mostly attributed to radiation-induced retinopathy, optic neuropathy, and secondary glaucoma. Enucleation was carried out in 14 patients (9.5%) because of local recurrence or severe side effects.

CONCLUSION

Radiation-induced optic neuropathy is an expected issue after proton beam therapy of parapapillary choroidal melanoma, and visual impairment is common during long-term follow-up, but some useful vision can be preserved in a considerable number of patients.

The American Brachytherapy Society consensus guidelines for plaque brachytherapy of uveal melanoma and retinoblastoma

PURPOSE

To present the American Brachytherapy Society (ABS) guidelines for plaque brachytherapy of choroidal melanoma and retinoblastoma.

METHODS AND MATERIALS

An international multicenter Ophthalmic Oncology Task Force (OOTF) was assembled to include 47 radiation oncologists, medical physicists, and ophthalmic oncologists from 10 countries. The ABS-OOTF produced collaborative guidelines, based on their eye cancer-specific clinical experience and knowledge of the literature. This work was reviewed and approved by the ABS Board of Directors as well as within the journal's peer-reivew process.

RESULTS

The ABS-OOTF reached consensus that ophthalmic plaque radiation therapy is best performed in subspecialty brachytherapy centers. Quality assurance, methods of plaque construction, and dosimetry should be consistent with the 2012 joint guidelines of the American Association of Physicists in Medicine and ABS. Implantation of plaque sources should be performed by subspecialty-trained surgeons. Although there exist select restrictions related to tumor size and location, the ABS-OOTF agreed that most melanomas of the iris, ciliary body, and choroid could be treated with plaque brachytherapy. The ABS-OOTF reached consensus that tumors with gross orbital extension and blind painful eyes and those with no light perception vision are unsuitable for brachytherapy. In contrast, only select retinoblastomas are eligible for plaque brachytherapy. Prescription doses, dose rates, treatment durations, and clinical methods are described.

CONCLUSIONS

Plaque brachytherapy is an effective eye and vision-sparing method to treat patients with intraocular tumors. Practitioners are encouraged to use ABS-OOTF guidelines to enhance their practice.

Current and emerging treatment options for uveal melanoma

Uveal melanoma (UM) is the most common primary malignant intraocular tumor in adults, with a 10-year cumulative metastatic rate of 34%. The most common site of metastasis is the liver (95%). Unfortunately, the current treatment of metastatic UM is limited by the lack of effective systemic therapy. Options for the management of the primary intraocular tumor include radical surgery as well as conservative treatments in order to preserve visual acuity. For metastatic disease, several approaches have been described with no standard method. Nevertheless, median survival after liver metastasis is poor, being around 4–6 months, with a 1-year survival of 10%–15%. In this review, the authors summarize current and promising new treatments for UM.

Palladium-103 radiation therapy for small choroidal melanoma

PURPOSE

To evaluate outcomes after ophthalmic plaque radiation therapy for small choroidal melanomas.

DESIGN

Retrospective study, case series.

PARTICIPANTS

Seventy-two patients with choroidal melanomas ≥1.5 and ≤2.4 mm apical height and ≤10 mm width treated between 2002 and 2012, with a minimum follow-up of 8 months.

METHODS

All patients were treated with palladium-103 plaque brachytherapy. Mean radiation dose to the tumor apex was 82.4 Gy (range, 70.0-102 Gy).

MAIN OUTCOME MEASURES

Local control, radiation complications, visual acuity, and metastatic rate.

RESULTS

Plaque radiotherapy provided 100% local tumor control and eye retention at a mean 54 months of observation (95% confidence interval, 46-63 months). The most common long-term brachytherapy-related complications were radiation maculopathy (43.1%) and radiation optic neuropathy (20.8%) developing at a mean of 27 months (range, 9-72 months) after irradiation. In this series, 94.4% of patients maintained 20/200 or better vision. There has been no small choroidal melanoma-related metastasis.

CONCLUSIONS

Palladium-103 plaque radiation therapy offered excellent local control and visual acuity outcomes for patients with small choroidal melanoma.

Dosimetry of (125)I and (103)Pd COMS eye plaques for intraocular tumors: report of Task Group 129 by the AAPM and ABS

Dosimetry of eye plaques for ocular tumors presents unique challenges in brachytherapy. The challenges in accurate dosimetry are in part related to the steep dose gradient in the tumor and critical structures that are within millimeters of radioactive sources. In most clinical applications, calculations of dose distributions around eye plaques assume a homogenous water medium and full scatter conditions. Recent Monte Carlo (MC)-based eye-plaque dosimetry simulations have demonstrated that the perturbation effects of heterogeneous materials in eye plaques, including the gold-alloy backing and Silastic insert, can be calculated with reasonable accuracy. Even additional levels of complexity introduced through the use of gold foil "seed-guides" and custom-designed plaques can be calculated accurately using modern MC techniques. Simulations accounting for the aforementioned complexities indicate dose discrepancies exceeding a factor of ten to selected critical structures compared to conventional dose calculations. Task Group 129 was formed to review the literature; re-examine the current dosimetry calculation formalism; and make recommendations for eye-plaque dosimetry, including evaluation of brachytherapy source dosimetry parameters and heterogeneity correction factors. A literature review identified modern assessments of dose calculations for Collaborative Ocular Melanoma Study (COMS) design plaques, including MC analyses and an intercomparison of treatment planning systems (TPS) detailing differences between homogeneous and heterogeneous plaque calculations using the American Association of Physicists in Medicine (AAPM) TG-43U1 brachytherapy dosimetry formalism and MC techniques. This review identified that a commonly used prescription dose of 85 Gy at 5 mm depth in homogeneous medium delivers about 75 Gy and 69 Gy at the same 5 mm depth for specific (125)I and (103)Pd sources, respectively, when accounting for COMS plaque heterogeneities. Thus, the adoption of heterogeneous dose calculation methods in clinical practice would result in dose differences >10% and warrant a careful evaluation of the corresponding changes in prescription doses. Doses to normal ocular structures vary with choice of radionuclide, plaque location, and prescription depth, such that further dosimetric evaluations of the adoption of MC-based dosimetry methods are needed. The AAPM and American Brachytherapy Society (ABS) recommend that clinical medical physicists should make concurrent estimates of heterogeneity-corrected delivered dose using the information in this report's tables to prepare for brachytherapy TPS that can account for material heterogeneities and for a transition to heterogeneity-corrected prescriptive goals. It is recommended that brachytherapy TPS vendors include material heterogeneity corrections in their systems and take steps to integrate planned plaque localization and image guidance. In the interim, before the availability of commercial MC-based brachytherapy TPS, it is recommended that clinical medical physicists use the line-source approximation in homogeneous water medium and the 2D AAPM TG-43U1 dosimetry formalism and brachytherapy source dosimetry parameter datasets for treatment planning calculations. Furthermore, this report includes quality management program recommendations for eye-plaque brachytherapy.