High intensity 125-iodine (125I) plaque treatment of uveal melanoma

125I plaque brachytherapy for anterior uveal melanomas

PURPOSE

To describe the results of 125I plaque brachytherapy of uveal melanomas anterior to the equator in terms of local control and the associated complications while trying to identify their risk factors (patients' demographic data, ocular, and tumour characteristics).

METHODS

Retrospective analysis of a series of patients treated by 125I between 1990 and 2000 in a single institution. The main outcome measures are evaluation of local tumour control and complications associated with 125I plaque brachytherapy of these melanomas.

RESULTS

During the study period, 136 patients were treated for an anterior tumour. The median follow-up was 62 months. The overall 5-year survival rate was 88.3%, the 5-year metastasis rate was 4% and the local recurrence rate was 1.5%. The mean final visual acuity was 20/40. The ocular complications most frequently observed at 5 years were cataract (50.3%), maculopathy (18.3%), intraocular inflammation (19.3%), and glaucoma (10.6%). Optic neuropathy, retinal detachment, keratitis, and intravitreous haemorrhage were also described. Risk factors for worse survival were age greater than 65 years and initial tumour thickness greater than 4 mm. Risk factors for the development of cataract were age more than 65 years old, male gender, and tumour diameter of more than 10 mm. Risk factors for intraocular inflammation were tumour thickness of more than 4 mm and invasion of the ciliary body.

CONCLUSIONS

The use of 125I plaque brachytherapy to treat melanomas situated anterior to the equator allows good local and systemic control with a low rate of macular and optic disc complications. The most frequent complication was cataract formation.

Iodine brachytherapy as an alternative to enucleation for large uveal melanomas

PURPOSE

To evaluate the safety and efficacy of iodine 125 plaque brachytherapy (IBT) for large uveal melanomas.

DESIGN

Retrospective, nonrandomized comparative trial (historical control).

PARTICIPANTS

One hundred twenty-one consecutive patients with a large uveal melanoma according to the Collaborative Ocular Melanoma Study (COMS) criteria who attended a national ocular oncology service.

METHODS

Ninety-seven patients (80%) underwent primary IBT (mean dose to tumor apex, 87 Gy) with noncollimated 20- to 25-mm plaques. Assessment of metastatic disease at death and visual outcome followed COMS guidelines. Time to low vision (20/70 or worse) and blindness (loss of 20/400 vision) in the study eye were modeled by Cox proportional hazards regression, based on both single- and repeated-failure data sets. Person-years of retained vision were calculated.

MAIN OUTCOME MEASURES

All-cause and melanoma-specific survival, local and distant recurrence, and preservation of vision and cosmesis.

RESULTS

Median tumor height was 10.7 mm (range, 4.5-16.8 mm), and largest basal tumor diameter was 16.1 mm (range, 7.3-25.0 mm). The Kaplan-Meier estimate for all-cause and melanoma-specific survival was 62% (95% confidence interval [CI], 49%-72%) and 65% (95% CI, 52%-75%) at 5 years. The corresponding estimate for local tumor recurrence was 6% (95% CI, 2%-14%) and for major cosmetic abnormality was 38% (95% CI, 26%-52%). The median visual acuity in the study eye was 20/100 at baseline and 20/1600 at 2 years after treatment. The Kaplan-Meier estimate for avoiding low vision and blindness was 11% (95% CI, 4%-24%) and 26% (95% CI, 16%-37%) at 2 years, respectively. Tumor height and location entirely posterior to the ora serrata were the most robust predictors of visual loss. In this series, 49 person-years without low vision (median, 0.6 years; range, 0.04-8.2 years) and 111 person-years without blindness (median, 1.0 years; range, 0.03-8.6 years) in the treated eye were conserved.

CONCLUSIONS

Iodine 125 plaque brachytherapy seems to be a safe and effective alternative to enucleation with regard to survival and local tumor control. It provides a fair chance of preserving the eye with acceptable cosmesis and a reasonable chance of conserving useful vision for 1 to 2 years.

The American Brachytherapy Society recommendations for brachytherapy of uveal melanomas

PURPOSE

This article presents the American Brachytherapy Society (ABS) guidelines for the use of brachytherapy for patients with choroidal melanomas.

METHODS

Members of the ABS with expertise in choroidal melanoma formulated brachytherapy guidelines based upon their clinical experience and a review of the literature. The Board of Directors of the ABS approved the final report.

RESULTS

Episcleral plaque brachytherapy is a complex procedure and should only be undertaken in specialized medical centers with expertise in this sophisticated treatment program. Recommendations were made for patient selection, techniques, dose rates, and dosages. Most patients with very small uveal melanomas (<2.5 mm height and <10 mm in largest basal dimension) should be observed for tumor growth before treatment. Patients with a clinical diagnosis of medium-sized choroidal melanoma (between 2.5 and 10 mm in height and <16 mm basal diameter) are candidates for episcleral plaques if the patient is otherwise healthy and without metastatic disease. A histopathologic verification is not required. Small melanomas may be candidates if there is documented growth; some patients with large melanomas (>10 mm height or >16 mm basal diameter) may also be candidates. Patients with large tumors or with tumors at peripapillary and macular locations have a poorer visual outcome and lower local control that must be taken into account in the patient decision-making process. Patients with gross extrascleral extension, ring melanoma, and tumor involvement of more than half of the ciliary body are not suitable for plaque therapy. For plaque fabrication, the ophthalmologist must provide the tumor size (including basal diameters and tumor height) and a detailed fundus diagram. The ABS recommends a minimum tumor (125)I dose of 85 Gy at a dose rate of 0.60-1.05 Gy/h using AAPM TG-43 formalism for the calculation of dose. NRC or state licensing guidelines regarding procedures for handling of radioisotopes must be followed.

CONCLUSIONS

Brachytherapy represents an effective means of treating patients with choroidal melanomas. Guidelines are established for the use of brachytherapy in the treatment of choroidal melanomas. Practitioners and cooperative groups are encouraged to use these guidelines to formulate their treatment and dose reporting policies. These guidelines will be modified as further clinical results become available.

The COMS randomized trial of iodine 125 brachytherapy for choroidal melanoma: IV. Local treatment failure and enucleation in the first 5 years after brachytherapy. COMS report no. 19

OBJECTIVE

To describe the frequency and predictors of local treatment failure and enucleation after iodine 125 (I(125)) brachytherapy in patients with choroidal melanoma treated and followed up in a large randomized clinical trial.

DESIGN

Prospective, noncomparative, interventional case series within a randomized, multicenter clinical trial.

PARTICIPANTS

Patients enrolled in the Collaborative Ocular Melanoma Study (COMS) trial of enucleation versus brachytherapy between February 1987 and July 1998; tumors measured 2.5 to 10.0 mm in apical height and no more than 16.0 mm in longest basal dimension.

METHODS

I(125) brachytherapy was administered via episcleral plaque according to a standard protocol. Follow-up ophthalmic evaluations, including ophthalmic ultrasound and fundus photography, were performed according to a standard protocol at baseline, every 6 months thereafter for 5 years, and subsequently at annual intervals. Survival analysis methods were used to estimate the cumulative risk of postirradiation treatment failure and enucleation. Factors associated with treatment failure and enucleation of plaqued eyes were evaluated using Cox proportional hazards analysis.

MAIN OUTCOME MEASURES

Reports of enucleation and of local treatment failure, defined as tumor growth, recurrence, or extrascleral extension, derived from clinical reports based on echographic and photographic documentation.

RESULTS

As of September 30, 2000, 638 of the 650 patients randomized to brachytherapy and so treated had been followed up for 1 year or longer, and 411 had been followed up for at least 5 years. Sixty-nine eyes were enucleated during the first 5 years after brachytherapy, and treatment failure was reported for 57 eyes. The Kaplan-Meier estimate of proportion of patients undergoing enucleation by 5 years was 12.5% (95% confidence interval [CI], 10.0%-15.6%); the risk of treatment failure was 10.3% (95% CI, 8.0%-13.2%). Treatment failure was the most common reason for enucleation within 3 years of treatment; beyond 3 years, ocular pain was most common. Risk factors for enucleation were greater tumor thickness, closer proximity of the posterior tumor border to the foveal avascular zone, and poorer baseline visual acuity in the affected eye. Risk factors for treatment failure were older age, greater tumor thickness, and proximity of the tumor to the foveal avascular zone. Local treatment failure was associated weakly with reduced survival after controlling for baseline tumor and personal characteristics (adjusted risk ratio, 1.5; P = 0.08).

CONCLUSIONS

Local treatment failure and enucleation were relatively infrequent events after I(125) brachytherapy within the COMS. Treatment failure typically occurred early and was associated weakly with poorer survival. The COMS randomized trial documented the absence of a clinically or statistically significant difference in survival for patients randomly assigned to enucleation versus brachytherapy. This analysis documents the efficacy of brachytherapy to achieve sustained local tumor control and to conserve the globe.

Posttreatment visual acuity in patients treated with episcleral plaque therapy for choroidal melanomas: dose and dose rate effects

PURPOSE

To determine the relationship between the long-term visual function and the dose and dose rates delivered to critical ocular structures in patients with choroidal melanoma treated with 125I episcleral plaque radiotherapy.

MATERIALS AND METHODS

From 1987 to 1994, 63 patients underwent 125I episcleral plaque (Collaborative Ocular Melanoma Study [COMS] design) application for the treatment of choroidal melanoma. The mean tumor height was 4.5 mm (range 1.7-8.3). Doses and dose rates at the tumor apex, macula, and optic disc were calculated. Forty-three records were scored to assess whether a decrease in visual acuity of >2 lines on a standard Snellen eye chart had occurred. Patient age and the presence of hypertension or diabetes were noted. Statistical analysis was performed to assess both the rate at which visual decline had occurred and the presence of significant factors that had contributed to this decline.

RESULTS

With a median follow-up of 36 months, the 3-year actuarial survival rate was 93.6%. The 3-year actuarial local control rate was 86.9%. The median time to visual loss after therapy was 18.7 months. The 3-year actuarial rate of visual preservation was 40.5%. Multivariate analysis demonstrated higher macula dose rates (p = 0.003) to forecast visual decline. Macula dose rates of 111 +/- 11.1 cGy/h were associated with a 50% risk of significant visual loss.

CONCLUSION

Patients in our series treated with 125I plaque brachytherapy for choroidal melanoma experienced favorable tumor control, but with a measurable incidence of visual decline. Higher dose rates to the macula correlated strongly with poorer posttreatment visual outcome. This information may be valuable in selecting the optimal dose rates to treat choroidal melanomas and to predict the risk of visual decline.

Amelanotic choroidal nevus and melanoma: cytology, tumor size, and pigmentation as prognostic indicators

BACKGROUND

Choroidal nevi are fairly common lesions of the posterior pole that can sometimes transform into melanoma, and it is thought that most choroidal melanomas arise from preexisting nevi. Occasionally, these lesions present as nonpigmented or amelanotic variations of their pigmented counterparts. Recent studies suggest a relationship between tumor pigmentation and risk of growth and metastasis, with a better prognosis for lightly pigmented or amelanotic lesions.

CASE REPORTS

A case of an amelanotic choroidal nevus and melanoma are presented. In Case 1, a 26-year-old white female was found to have a large amelanotic nevus in the right eye. After 7 years of periodic observation, the lesion has not changed. In Case 2, a 51-year-old white male was diagnosed with a large amelanotic melanoma in the left eye. Due to extensive involvement of the optic nerve, the patient underwent enucleation. Histological evaluation confirmed the lesion as a mixed-cell type malignant amelanotic melanoma.

CONCLUSION

Management of choroidal nevi generally consists of periodic observation, and the most widely accepted management of choroidal melanoma is observation, radiotherapy, and transpupillary thermotherapy or enucleation. The therapeutic modality of choice for melanoma will vary depending on the size, growth, and location of the lesion. In addition, recent studies suggest an association between heavy tumor pigmentation, tumor size, cell type, and risk of metastasis. Although many variables will influence the final treatment option, pigmentation of the lesion should also be considered.

Establishment of IPC 227 cells as human xenografts in rabbits: a model of uveal melanoma

This study was designed in order to evaluate the feasibility of establishing an animal model of human uveal melanoma. IPC227, a cell line established from the biopsy of a patient with a spindle cell ciliary body melanoma, was transplanted into the anterior chamber of the eye in immunosuppressed New Zealand rabbits. In a second step, a tumour fragment from the anterior chamber was implanted transclerally into the posterior choroid. Complete ophthalmological examinations were then performed on the animals. Characteristic growth patterns were noted depending on the location of implantation. In the anterior chamber, diffuse, flat, heavily pigmented tumours appeared 8 days after the injection of the cell suspension that covered the iris and the angle by day 25, with a success rate of 100%. Nodular, lightly pigmented tumours were obtained 6-7 weeks after subchoroidal implantation, with a 25% success rate. Clinical examination, including fundus photography, ultrasound and magnetic resonance imaging, demonstrated the same characteristics as those of human uveal melanoma, confirming the value of this model for the evaluation of new therapeutic and diagnostic methods in the management of uveal melanoma.

Ten-year follow-up of helium ion therapy for uveal melanoma

PURPOSE

To examine the results of helium ion irradiation in 218 patients with uveal melanoma treated more than 10 years ago.

METHOD

A retrospective review was made of 218 patients (218 eyes) treated with helium ion radiation for uveal melanoma between 1978 and 1984.

RESULTS

After helium ion irradiation, 208 (95.4%) of 218 eyes had local tumor control. Ten years after irradiation, 46 (22.4%) of 218 eyes had been enucleated; the majority of enucleations (37 of 46) resulted from anterior ocular segment complications. Ten years after radiation, 102 (46.8%) of the 218 patients were dead; 51 had non-melanoma-related deaths and 51 had died of metastatic melanoma. Best-corrected visual acuity after radiation was greater than 20/40 in 21 (23%) of 93 eyes of the patients who were alive and who had retained their eyes 10 or more years after treatment. In patients with tumors less than 6 mm in height and more than 3 mm distant from the nerve or the fovea, 13 (72%) of 18 retained visual acuity greater than 20/40. In contrast, only 11% of the patients with either thicker tumors or those close to the nerve or fovea retained that level of visual acuity.

CONCLUSIONS

Helium ion irradiation of uveal melanoma is associated with good local tumor control and reasonable retention of the treated eye 10 years after treatment. In eyes with tumors less than 6 mm in thickness and more than 3 mm distant from the optic nerve and fovea, many retain excellent vision.

Clinical indications for brachytherapy

Brachytherapy, or placing radioactive sources either temporarily or permanently into or near a malignant tumor, is a long-established cancer treatment method. During the past 25 years, brachytherapy has become safer and more versatile than earlier radium therapy, and its indications have increased dramatically during this period. One estimate is that at least 5-10% of all patients needing radiation therapy require brachytherapy. The site-specific clinical indications and methods for brachytherapy implementation are described.

Choroidal melanoma: a review of the experience of the Sydney Eye Hospital Professorial Unit 1979-1995

PURPOSE

This study examines 90 patients presenting with choroidal or ciliochoroidal melanoma to the Professorial Unit at the Sydney Eye Hospital. The indications for treatment, and the outcome for the eye and vision are presented together with an account of mortality and the incidence of metastases.

METHODS

A retrospective analysis of 90 choroidal melanoma patients managed by one surgeon over a 16-year period was undertaken. Initial findings, investigations performed, incidence of metastatic disease, treatment received and complication rates and mortality, where applicable, were recorded.

RESULTS

The group was followed for an average of 64 months (range, 5-172 months). Primary treatment was with either iodine125 (125I) brachytherapy, local excision or enucleation. Radiation retinopathy was prominent in 125I cases resulting in poor visual acuity when the tumour resided in the posterior pole. Local excision even of large tumours was effective particularly if peripheral. Overall metastatic disease was seen in 11% with 5-year survival rates for the metastatic group being 10%. Prognosis after diagnosis of metastases was poor.

CONCLUSIONS

Specific therapy for choroidal melanoma must relate to the size and location of the tumour at the time of diagnosis. Visual outcome relates directly to the proximity of the tumour to the optic nerve and fovea. Metastatic disease latency can be prolonged; therefore caution about prognosis is required long after therapy is given. The 5-year survival is encouraging with all forms of therapy. However, as the natural history of ocular melanoma is variable and not fully delineated it is important to monitor the effects of conservative therapy. Further long-term survival data is required to distinguish whether one form of treatment is advantageous over the others, although case-control studies are difficult for ethical and practical reasons. In this regard the Collaborative Ocular Melanoma Study (COMS) will provide further evidence for the safety and efficacy of conservative therapy with brachytherapy compared to enucleation.

Radiation related complications after ruthenium plaque radiotherapy of uveal melanoma

AIMS/BACKGROUND

To analyse radiation related complications and secondary enucleation after irradiation of malignant uveal melanoma with ruthenium-106 plaques.

METHODS

A series of 100 consecutive eyes irradiated in 1981-91 was analysed using the life table method and the Cox proportional hazards model. The median apical and scleral tumour dose was 100 Gy (range 15-200 Gy) and 1000 Gy (range 200-1200 Gy), respectively. The median follow up time was 2.8 and 2.0 years (range 1 month to 10 years) for anterior and posterior segment complications, respectively.

RESULTS

The 3 and 5 year probabilities of being without radiation cataract were 73% and 63%, without neovascular glaucoma 91% and 81%, without vitreous haemorrhage 83% and 74%, without radiation maculopathy 85% and 70%, and without radiation optic neuropathy 90% and 88%, respectively. The risk of radiation cataract was highest with large tumour size (T1 + T2 v T3, p = 0.0027; height < or = 5 v > 5 mm, p = 0.029; largest basal diameter (LBD) < or = 15 v > 15 mm, p < 0.0001) and location of anterior tumour margin anterior v posterior to the equator (p = 0.0003); the risk of neovascular glaucoma with large size (T1 + T2 v T3, p = 0.039; LBD < or = 15 mm v 15 mm, p = 0.021); and the risk of maculopathy and optic neuropathy with proximity of the posterior tumour margin to the fovea and the optic disc (< or = 1.5 v > 1.5 mm; p = 0.030 and p = 0.0004, respectively). In Cox's multivariate analysis the strongest risk indicator for radiation cataract (RR 1.5, 95% CI 1.4-1.6) and vitreous haemorrhage (RR 1.6, 95% CI 1.4-1.8) was the height of the tumour; for neovascular glaucoma the TNM class (RR 6.2, 95% CI 2.7-13.8); for radiation maculopathy location of posterior tumour margin within 2 mm from the fovea (RR 3.4, 95% CI 2.0-6.0); and for radiation optic neuropathy location of tumour margin within 1 DD of the optic disc (RR 6.1, 95% CI 3.0-12.4). The 3 and 5 year probabilities of avoiding enucleation were 92% and 85%, respectively. Ten eyes were enucleated--six because of recurrent tumour growth, three because of treatment complications, and one because of mistakenly suspected extraocular growth.

CONCLUSION

The results suggest that the frequency of radiation related complications after ruthenium brachytherapy of uveal melanoma is acceptable, in particular as regard irradiation of small and medium sized tumours for which ruthenium therapy generally is recommended.

125I plaque therapy for uveal melanoma. Analysis of the impact of time and dose factors on local control

BACKGROUND

125I episcleral plaque therapy has gained wide acceptance for the treatment of uveal melanoma because of its potential to preserve vision, salvage the globe, and provide good local control. A rigorous analysis of the optimum radiation dose, dose rate, and overall treatment time has not been reported with this technique.

METHODS

One hundred fifty patients with uveal melanoma treated with 125I plaques between 1982 and 1990 and included in the uveal melanoma study (UMS) database of the Wills Eye Hospital were analyzed. Mean patient age was 60.7 years (range: 17.7-84.6 years). Initial mean tumor size was 9.7 x 8.5 x 3.7 mm with a range of 4.5 to 21.5 mm in basal dimension and 1.2 to 11.8 mm in height. Mean dose to the tumor apex was 94.77 gray (Gy) (29.5-141 Gy). Mean dose rate to the tumor apex was 92.9 cGy/hr (10-292 cGy/hr); the mean dose to the base was 359 Gy (181-692 Gy); the mean dose rate to the base was 348 cGy/hr (112-893 cGy/hr); and mean duration of treatment was 124.7 hours (range: 28-333 hours)

RESULTS

With a median follow-up of 68 months, there have been 33 local failures. Mean time to local failure was 19 months (range: 6-78 months). Actuarial local control is 81% at 5 years. Multivariate analysis demonstrates significant correlation of local failure with larger tumor dimension (P = 0.0046), close proximity to the optic disc (P = 0.0029), lower radiation dose to the tumor apex (P = 0.03), lower radiation dose rate to the tumor apex and base (P = 0.01 and 0.03), and longer overall treatment time (P = < 0.0001).

CONCLUSIONS

This retrospective analysis reinforces the importance of dose rate, minimum tumor dose, overall treatment time, maximum tumor basal dimension, and proximity to the optic nerve in the treatment of uveal melanoma.