Radiobiological doses, tumor, and treatment features influence on outcomes after epiescleral brachytherapy. A 20-year retrospective analysis from a single-institution: part II

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.

AAPM Task Group Report 267: A joint AAPM GEC-ESTRO report on biophysical models and tools for the planning and evaluation of brachytherapy

Brachytherapy utilizes a multitude of radioactive sources and treatment techniques that often exhibit widely different spatial and temporal dose delivery patterns. Biophysical models, capable of modeling the key interacting effects of dose delivery patterns with the underlying cellular processes of the irradiated tissues, can be a potentially useful tool for elucidating the radiobiological effects of complex brachytherapy dose delivery patterns and for comparing their relative clinical effectiveness. While the biophysical models have been used largely in research settings by experts, it has also been used increasingly by clinical medical physicists over the last two decades. A good understanding of the potentials and limitations of the biophysical models and their intended use is critically important in the widespread use of these models. To facilitate meaningful and consistent use of biophysical models in brachytherapy, Task Group 267 (TG-267) was formed jointly with the American Association of Physics in Medicine (AAPM) and The Groupe Européen de Curiethérapie and the European Society for Radiotherapy & Oncology (GEC-ESTRO) to review the existing biophysical models, model parameters, and their use in selected brachytherapy modalities and to develop practice guidelines for clinical medical physicists regarding the selection, use, and interpretation of biophysical models. The report provides an overview of the clinical background and the rationale for the development of biophysical models in radiation oncology and, particularly, in brachytherapy; a summary of the results of literature review of the existing biophysical models that have been used in brachytherapy; a focused discussion of the applications of relevant biophysical models for five selected brachytherapy modalities; and the task group recommendations on the use, reporting, and implementation of biophysical models for brachytherapy treatment planning and evaluation. The report concludes with discussions on the challenges and opportunities in using biophysical models for brachytherapy and with an outlook for future developments.

Retrospective Analysis of Radiation-Induced Complications of Uveal Melanoma Patients Treated With Brachytherapy in the Era of Anti-VEGF

PURPOSE

To associate clinical factors and radiation doses delivered by iodine-125 plaque brachytherapy to visual outcomes and development of radiation-induced ocular complications in patients with uveal melanoma in the era of anti-vascular endothelial growth factor (anti-VEGF) injections.

DESIGN

Retrospective cohort study.

METHODS

A retrospective chart review was performed for 225 patients treated with iodine-125 brachytherapy for uveal melanoma. The effects of radiation doses (focal doses, average dose to the entire eye, and integral dose) on visual outcomes and development of radiation complications (radiation retinopathy, radiation optic neuropathy, vitreous hemorrhage, and neovascular glaucoma) were analyzed using multivariate Cox regression snalysis.

RESULTS

Median follow-up was 33.6 months (range, 12-105.6 months). Radiation retinopathy was associated with younger age, tumor distance to optic nerve <6 mm, and maximum radiation dose to fovea. Radiation optic neuropathy was associated with White race, tumor distance to optic nerve <6 mm, and integral radiation dose. Vitreous hemorrhage was associated with White race and integral radiation dose. Incidence of neovascular glaucoma was low in our study, with 2 patients (0.9%) developing the complication. Of the 123 patients who developed radiation retinopathy, 82 patients (66.7% of radiation retinopathy patients, 37.3% of total patients) received anti-VEGF injections.

CONCLUSIONS

Our study found multiple associations between radiation doses and complications as well as visual outcomes on multivariate analysis. Given that the majority of our patients who developed radiation retinopathy received anti-VEGF injections, our study helps to illustrate the course and progression of radiation-induced complications in the new era of anti-VEGF.

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.

A Case of Circumscribed Choroidal Hemangioma Treated With Proton Beam Therapy and Followed Up for 15 Years

Circumscribed choroidal hemangiomas are rare and benign tumors but often have a progressive course and are complicated by retinal detachment and glaucoma. The effectiveness of external radiation for large tumors that are difficult to treat with photodynamic therapy was recently reported; however, few studies have conducted long-term follow-ups. We encountered a case of localized choroidal hemangioma that was treated with proton beam therapy and followed up for 15 years. A 37-year-old man was diagnosed with a 10 × 4 mm circumscribed choroidal hemangioma involving the macular area with retinal detachment. Proton beam therapy was performed at 26.4 Gy relative biological effectiveness (RBE) in 8 fractions. The choroidal hemangioma gradually shrank over three years, and the retinal detachment also improved. A cataract developed on the affected side 11 years after irradiation, and eye coordination issues developed 15 years after irradiation. Glaucoma was not observed during the follow-up period; however, visual acuity did not recover, and the patient developed light perception. Although vision was not preserved, proton beam therapy effectively shrank the tumor and maintained quality of life.

A study comparing baseline and best-corrected visual acuity after iodine-125 episcleral brachytherapy in uveal melanoma

Purpose

The aim of this study was to analyze the course of visual acuity (VA) in visual outcomes of patients treated with iodine-125 (125I) brachytherapy in our center, based on original VA before treatment.

Material and methods

Visual acuity was prospectively assessed using a case series of 305 patients treated with 125I between 1996 and 2022. To examine how VA behaves over time, we divided patient sample into 4 groups: (1) Patients with visual acuity of less than V ≤ 0.1 at baseline; (2) Patients with low to moderate VA, ranging 0.1 < V < 0.4; (3) Patients with moderate-high VA, ranging 0.4 < V < 0.8; (4) Patients with very high VA of V > 0.8. Each of the four groups was studied separately over a 60-month period to determine the percentage of patients with VA improvement, worsening, or with the same VA status. Finally, visual outcomes over time were estimated with 95% confidence interval (CI) using Kaplan-Meier analysis, and VA maintenance rates were reported at 1, 3, 5, 10, 15, and 20 years of follow-up.

Results

The median follow-up time was 78.2 months (range, 6-254 months). The cumulative probabilities of survival analysis at 1, 3, 5, and 10 years were 16%, 3%, 2%, and none for the first sub-group; 46%, 20%, 17%, and 14% for the second; 65%, 53%, 29%, and 15% for the third; and 86%, 56%, 48%, and 41% for the fourth sub-group. The median survival in years was 0.30, 0.80, 3.10, and 4.40 for each sub-cohort, respectively.

Conclusions

The decrease and maintenance of VA depends on the initial VA of patients. Most patients experience a marked worsening of their VA, regardless of their VA status before treatment with episcleral brachytherapy. Patients with a higher baseline VA retain VA best over time.

Radiotherapy in Uveal Melanoma: A Review of Ocular Complications

Uveal melanoma represents the most prevalent form of primary malignant intraocular tumor in adults. Historically, enucleation was considered the gold-standard approach in the treatment of uveal melanoma. Currently, radiotherapy is the most commonly used therapy, aiming at a better quality of life. However, radiotherapy can result in several ocular complications, some of which may be vision-threatening. Radiation-induced dry eye, scleral necrosis, cataract, rubeosis iridis, neovascular glaucoma, radiation retinopathy, maculopathy, and optic neuropathy are the most common complications. This article aims to summarize the current literature regarding the ocular complications after radiotherapy, as well as their clinical features, risk factors, and management strategies. A thorough understanding of these issues is crucial for ophthalmologists and oncologists to provide optimal patient care, improve visual outcomes, and minimize long-term complications.

Incidence and Risk Factors for Secondary Glaucoma in Eyes with Uveal Melanoma

PURPOSE

To estimate incidence of and analyze risk factors for developing secondary glaucoma in eyes with uveal melanoma before and after diagnosis.

DESIGN

A cross-sectional, population-based cohort study.

PARTICIPANTS

Seven hundred eighty-one patients (median age, 64 years; range, 14-93) consecutively diagnosed with uveal melanoma from 1997 to 2012 in a national ocular oncology service, 708 (91%) of whom received ruthenium (50%) or iodine (50%) brachytherapy.

METHODS

Patient, tumor, treatment, and follow-up data were collected prospectively. Frequency and associations of melanoma-related glaucoma at tumor diagnosis were assessed. Incidence of developing secondary glaucoma after diagnosis was estimated by Kaplan-Meier analysis. Independent risk factors were modeled using Cox regression.

MAIN OUTCOME MEASURES

Melanoma-related glaucoma and related risk factors.

RESULTS

Forty-five patients (5.8%; 95% confidence interval [CI], 4.2-7.6) had tumor-related secondary glaucoma at diagnosis, 34 (76%) from a narrow-to-closed angle (25 had direct angle invasion) and 10 (22%) from anterior neovascularization. Synchronous metastases were common in patients with initial secondary glaucoma (11% vs. 1.2% with incident glaucoma, P = 0.005). Patients with secondary glaucoma were often male (58% vs. 48% without glaucoma; P = 0.010) and had larger tumors (median thickness, 9.1 vs. 4.0 mm; P < 0.001) involving the ciliary body (43% vs. 21%; P < 0.001) with retinal detachment (53% vs. 30%; P < 0.001). One hundred and sixty-eight patients 165 of which were treated with brachytherapy developed incident tumor- or treatment-related secondary glaucoma a median of 1.7 years (range, 0.1-13.6) after tumor diagnosis. Cumulative proportion of developing secondary glaucoma was 23% (95% CI, 20-27) at 5 years. The most common mechanism was neovascularization in 119 patients (71%; 95% CI, 63-78). By multivariable regression, initial retinal detachment 3 to 4 quadrants (hazard ratio [HR], 2.18; P < 0.001), initial intraocular pressure 17 mmHg or higher (HR, 1.64; P = 0.01), and tumor thickness predicted incident secondary glaucoma.

CONCLUSIONS

Secondary glaucoma at initial uveal melanoma diagnosis predicts high risk of synchronous metastases. Although anterior neovascularization is the most common mechanism for secondary glaucoma after diagnosis, other mechanisms such as angle narrowing and anterior chamber hemorrhage are not infrequent. Initial retinal detachment and intraocular pressure with tumor thickness could inform interim assessments of intraocular pressure and neovascularization.

Retrospective analysis of secondary enucleation for uveal melanoma after plaque radiotherapy

Background

Uveal melanoma (UM) is the most common primary intraocular malignancy in adults. Plaque brachytherapy (PRT) is widely accepted as an effective globe-conserving treatment modality for UM. However, local treatment failure and complications lead to the enucleation of irradiated eyes. We conducted this study to explore the causes and long-term prognosis for UM patients who accepted secondary enucleation after plaque radiotherapy.

Methods

This was a retrospective cohort study. Data of patients who underwent secondary enucleation for UM after plaque radiotherapy, from July 2007 to July 2019, at Beijing Tongren Hospital were analyzed. Kaplan–Meier analysis was performed to assess the probability of indications, metastasis, and metastasis-related death. Cox regression analysis was used to analyze associations of the prognostic factors.

Results

Eight hundred and eighty patients were clinically diagnosed with uveal melanoma and initially treated by iodine-125 plaque radiotherapy, 132 of whom underwent secondary enucleation and pathological examination in the same hospital. Fifty-two (39.4%) eyes were enucleated simply because of uncontrollable neovascular glaucoma (NVG). Forty-four (33.3%) patients suffered from tumor recurrence. Tumor non-response occurred in 18 (13.6%) cases. Ten (7.6%) eyes received enucleation entirely due to other types of glaucoma. Failure to preserve the eyes for other reasons occurred in eight (6.1%) patients. At a median follow-up of 58.1 [IQR: 40.9–90.5] months, the systemic spread was detected in 45 (34.1%) patients, and 38 of them died. On multivariate analysis, tumor largest basal diameter (HR 1.15 [95% CI: 1.01, 1.31]), tumor non-response (HR 7.22 [95% CI: 2.63, 19.82]), and recurrence (HR 3.29 [95% CI: 1.54, 7.07]) were risk factors for metastasis. Increased age (HR 1.54 [95% CI: 1.07, 2.23]), tumor non-response (HR 7.91 [95% CI: 2.79, 22.48]), and recurrence (HR 3.08 [95% CI: 1.13, 7.23]) were risk factors for metastasis-related death.

Conclusions

NVG was the major reason for secondary enucleation for Chinese UM patients after PRT. Tumor non-response and recurrence were associated with a significantly higher risk of long-term metastasis and metastasis-related death.

Long-term relative survival in uveal melanoma: a systematic review and meta-analysis

Background

A large proportion of patients with uveal melanoma develop metastases and succumb to their disease. Reports on the size of this proportion vary considerably.

Methods

PubMed, Web of Science and Embase were searched for articles published after 1980. Studies with ≥100 patients reporting ≥five-year relative survival rates were included. Studies solely reporting Kaplan-Meier estimates and cumulative incidences were not considered, due to risk for competing risk bias and classification errors. A meta-analysis was performed using random-effects and weighted averages models, as well as a combined estimate based on curve fitting.

Results

Nine studies and a total of 18 495 patients are included. Overall, the risk of selective reporting bias is low. Relative survival rates vary across the population of studies (I2 48 to 97% and Qp < 0.00001 to 0.15), likely due to differences in baseline characteristics and the large number of patients included (τ2 < 0.02). The 30-year relative survival rates follow a cubic curve that is well fitted to data from the random-effects inverse-variance and weighted average models (R2 = 0.95, p = 7.19E−7). The estimated five, ten, 15, 20, 25 and 30-year relative survival rates are 79, 66, 60, 60, 62 and 67%, respectively.

Conclusions

The findings suggest that about two in five of all patients with uveal melanoma ultimately succumb to their disease. This indicates a slightly better prognosis than what is often assumed, and that patients surviving 20 years or longer may have a survival advantage to individuals of the same sex and age from the general population.

Radiobiological evaluation of organs at risk for electronic high-dose-rate brachytherapy in uveal melanoma: a radiobiological modeling study

Purpose

The objective of this study was to examine feasibility of single- or hypo-fraction of high-dose-rate (HDR) electronic brachytherapy (eBT) in uveal melanoma treatment.

Material and methods

Biologically effective doses (BED) of organs at risk (OARs) were compared to those of iodine-125-based eye plaque low-dose-rate brachytherapy (¹²⁵I LDR-BT) with vitreous replacement (VR). Single- or hypo-fractionated equivalent physical doses (SFEDs or HFEDs) for tumor were calculated from tumor BED of ¹²⁵I LDR-BT using linear-quadratic (LQ) and universal survival curve (USC) models. BED OARs doses to retina opposite the implant, macula, optic disc, and lens were calculated and compared among SFED, HFED, and ¹²⁵I LDR-BT. Electronic BT of 50 kVp was considered assuming dose fall-off as clinically equivalent to ¹²⁵I LDR-BT. All OARs BEDs were analyzed with and without silicone oil VR.

Results

For a single-fraction incorporating VR, the median/interquartile range of LQ (USC)-based BED doses of the retina opposite the implant, macula, optic disc, and lens were 16%/1.2% (33%/4%), 35%/19.5% (64%/17.7%), 37%/19% (75%/17.8%), and 27%/7.9% (68%/23.2%) of those for ¹²⁵I LDR-BT, respectively. SFED tumor values were 29.8/0.2 Gy and 51.7/0.5 Gy when using LQ and USC models, respectively, which could be delivered within 1 hour. SFED can be delivered within 1 hour using a high-dose-rate eBT. Even four-fraction delivery of HFED without VR resulted in higher OARs doses in the macula, optic disc, and lens (135 ~ 159%) than when using ¹²⁵I LDR-BT technique. A maximum p-value of 0.005 was observed for these distributions.

Conclusions

The simulation of single-fraction eBT, including vitreous replacement, resulted in significantly reduced OARs doses (16 ~ 75%) of that achieved with ¹²⁵I LDR-BT.

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.

Plaque brachytherapy for choroidal melanoma with vitreous haemorrhage: a therapeutic challenge

A 47-year-old man presented with profound loss of vision in right eye and relative afferent pupillary defect. On fundus examination, posterior pole details were obscured due to dense vitreous haemorrhage. B-scan ultrasonography was performed that revealed a mushroom-shaped hyperechoic lesion with medium internal reflectivity on A-scan ultrasonography. After performing contrast-enhanced MRI of the orbit, a diagnosis of choroidal melanoma was established. Patient was managed using plaque brachytherapy based on multiplanar MRI. This was followed 10 months later by pars plana vitrectomy and cataract extraction. Vision postoperatively improved to 20/60. A systematic clinical assessment along with supportive ancillary investigations augments diagnostic accuracy and reduces delay in definitive management.

Regression of posterior uveal melanoma following iodine-125 plaque radiotherapy based on pre-treatment tumor apical height

PURPOSE

The aim of this study was to analyze regression rates and local control of uveal melanoma patients treated with iodine-125 ( 125I) brachytherapy based on initial tumor apical height.

MATERIAL AND METHODS

Patients treated in a single institution from January 1st, 1996 to 2019 with 125I plaques (ROPES and COMS) for uveal melanoma were included in this study. Patients treated with brachytherapy for iris and those treated with transpupillary thermotherapy prior to brachytherapy were excluded. The sample was classified into 4 categories depending on initial apical tumor height (h0), i.e., h0 ≤ 2.5 (small), 2.5 < h0 ≤ 6.25 (small-medium), 6.25 < h0 ≤ 10 (medium-large), and h0 > 10 mm (large). Percentage of original tumor apical height (Δh) was collected during follow-ups. Patterns of regression were evaluated using linear least squares adjustments. Multivariable Cox regression were performed.

RESULTS

In total, 305 patients met the inclusion criteria, and 27, 166, 100, and 13 were considered for small, small-medium, medium-large, and large categories, respectively. Median follow-up was 82.4, 56.8, 76.1, 89.1, and 100.1 months for the entire cohort and each sub-group, respectively. Pattern of decrease when h0 ≤ 2.5 mm was not detectable. For the rest sub-groups, changes in height could be fitted using functional form: Δh (T) = ae-bT + c, R 2 ≥ 0.97. Multivariate Cox analysis factors predictive of local control failure revealed a hazard ratio (HR) of 6.1 (95% CI: 0.7-58.2%, p = 0.05) for patients who remained similar sized after treatment for small-medium tumors. For the rest sub-groups, Cox analysis did not indicate statistical significance in any single variable.

CONCLUSIONS

Height changes can be modeled by a negative exponential function for the first 7 years after treatment depending on the initial height, except for those less than 2.5 mm. Non-responding small-medium tumors multiply by 6 the probability of failure in local control.

Analysis of local recurrence causes in uveal melanoma patients treated with 125I brachytherapy - a single institution study

PURPOSE

To perform a retrospective analysis of factors which might affect the occurrence of a relapse of uveal melanoma after 125I brachytherapy.

MATERIAL AND METHODS

The analysis concerned 343 patients treated in the years 2001-2012. The effect on local recurrence of such factors as patient's sex, age, tumour size, shape, pigmentation, location, presence of orange pigment or petechiae on tumour surface, retinal detachment, and blood or dispersed pigment in vitreous body were studied. Additional analysis concerned physical properties of brachytherapy (total dose, irradiation dose applied to tumour apex and base and irradiation time). Two groups of patients were distinguished: with and without a relapse. The diagnostic criterion for the relapse was growth of the tumour base or height by 0.5 mm.

RESULTS

Local recurrence of the uveal melanoma was observed in 29 patients (8.5%). Recurrences occurred with significantly higher frequency (p < 0.001), when the anterior tumour edge involved the ciliary body. Patients' survival in relation to the moment the occurrence of the relapse was statistically significant for application time (p = 0.004) and tumour pigmentation (p = 0.010). The deaths of patients with a local relapse were most rare when brachytherapy lasted from 72 to 95.9 hours and most frequent in cases of brownish tumour pigmentation. Patient sex, tumour shape and size, presence of orange pigment, retinal detachment, petechiae and bleeding to vitreous body as well as the dose of irradiation to tumour top and base did not have any significant effect on relapse occurrence.

CONCLUSIONS

Treatment of uveal melanomas with 125I applicators allows for a high rate of positive local results. Nonetheless, the recurrence probability always exists. The involvement of the ciliary body could influence this. The survival depending on the time of relapse could be statistically significant for application time and dark-brown tumour pigmentation.

Treatment planning considerations for 125I eye plaque brachytherapy

Effective cancer brachytherapy requires a treatment plan that delivers high-dose to tumor, while minimizing the dose to critical normal tissues. Therefore, an accurate knowledge of the sources and magnitude of the techniques is essential for producing robust and well optimized-plans.

The purpose of this technical note is to establish general procedures and strategies for optimization and customization of the plaques loaded with radioactive seeds, particularly focusing on the definition of useful tactics to limit high doses to organs at risk and adapt the treatment time to the necessity of institution.

Personalized re-treatment strategy for uveal melanoma local recurrences after interventional radiotherapy (brachytherapy): single institution experience and systematic literature review

Purpose

To report the results of a patient’s tailored therapeutic approach using a second course of interventional radiotherapy (brachytherapy) in patients with locally recurrent uveal melanoma.

Material and methods

Patients who had already undergone ocular brachytherapy treated at our IOC (Interventional Oncology Center) were considered. Five patients who has received a second course of treatment with a plaque after local recurrences were included in our study. Re-irradiation was performed with Ruthenium-106 (prescribed dose to the apex 100 Gy) or with Iodine-125 plaques (prescribed dose to the apex 85 Gy). Moreover, a systematic literature search was conducted through three electronic databases, including Medline/PubMed, Scopus, and Embase.

Results

All patients were initially treated with Ruthenium-106 plaque; the re-irradiation was performed with Ruthenium-106 plaque in three cases and with Iodine in two cases. Mean time between the first and the second plaque was 56.8 months (range, 25-93 months). Local tumor control rate was 100%, no patient underwent secondary enucleation owing to re-treatment failure. Distant metastasis occurred in 1 patient after 6 months from re-treatment. After a median follow-up of 44.2 months (range, 26-65 months) from re-treatment, all patients experienced worsening of the visual acuity (median visual acuity was 0.42 at time of recurrence and decline to 0.24 at the most recent follow-up); cataract occurred in two cases, no patient developed scleral necrosis. We considered 2 papers for a systematic review.

Conclusions

In selected cases, especially in presence of marginal local recurrence, a personalized re-treatment strategy with a plaque may offer high probability of tumor control and organ preservation but worsening of visual acuity.