Proton beam radiotherapy of uveal melanoma

[Uveal and iridociliary melanomas in young patients : A retrospective analysis of 57 cases]

BACKGROUND

Uveal melanomas (UM) are rare malignancies in young patients. It is unknown if UM in young patients significantly differs from those in older patients concerning tumor size and localization, metastasis and genetics. The aim of this study was to evaluate the clinical course and tumor characteristics in young patients with UM.

MATERIAL AND METHODS

All patients with UM below the age of 32 years who had been treated at our hospital were included in the study. Patient age and sex, duration of symptoms, visual impairment, tumor size and location, genetics, therapy, follow-up interventions and tumor-associated deaths were documented.

RESULTS

A total of 57 patients (67 % male, mean age 24.7 years) were included in the study with an average symptomatic course of 5 months. Of the patients 8 (14 %) had an initial visual acuity of ≥ 0.9, 16 (28 %) 0.5-0.8, 22 (39 %) 0.05-0.4 and 9 (16 %) < 0.05 (no data for 2 patients, 4 %). After therapy visual acuity was < 0.05 in 54 % and 53 % of the tumors were choroidal UM (70 % juxtapapillary/circumpapillary), whereas 47 % were ciliochoroidal (54 % with iridociliary involvement). The average tumor size was 12.7 ± 3.6 mm with an average prominence of 6.2 ± 3.2 mm. Genetic evaluation (n = 16) revealed disomy 3 in 64 % and 54 % of the patients received radiotherapy with local application of ruthenium 106. In 46 % of cases follow-up interventions were neccessary including 70 % due to radiogenic retinopathy.

CONCLUSION

In young patients UM did not show any preferred localization. The majority of genetically evaluated tumors revealed disomy 3 with no significant correlation to tumor location. Independent of tumor size, location and therapy, approximately half of the patients needed follow-up interventions, predominantly due to radiogenic retinopathy.

Uveal Melanoma: Current Trends in Diagnosis and Management

Uveal melanoma, which is the most common primary intraocular malignancy in adults, arises from melanocytes within the iris, ciliary body and choroid. The diagnosis is based principally on clinical examination of the tumor with biomicroscopy and indirect ophthalmoscopy and confirmed by diagnostic techniques such as ultrasonography, fundus fluorescein angiography and optical coherence tomography. The clinical diagnosis of posterior uveal melanomas can be made when the classical appearance of a pigmented dome-shaped mass is detected on dilated fundus exam. Uveal melanomas classically show low to medium reflectivity on A-scan ultrasonography and on B-scan ultrasonography the tumor appears as a hyperechoic, acoustically hollow intraocular mass. Management of a suspicious pigmented lesion is determined by its risk factors of transforming into a choroidal melanoma, such as documentation of growth, thickness greater than 2 mm, presence of subretinal fluid, symptoms and orange pigment, margin within 3 mm of the optic disc, and absence of halo and drusen. Advances in the diagnosis and local and systemic treatment of uveal melanoma have caused a shift from enucleation to eye-conserving treatment modalities including transpupillary thermotherapy and radiotherapy over the past few decades. Prognosis can be most accurately predicted by genetic profiling of fine needle aspiration biopsy of the tumor before the treatment, and high-risk patients can now be identified for clinical trials that may lead to target-based therapies for metastatic disease and adjuvant therapy which aims to prevent metastatic disease.

Role of radiation therapy in melanomas: Systematic review and best practice in 2016

Radiotherapy has been used for skin cancers since early after the discovery of X-rays. The introduction of sophisticated surgery techniques and information of the general population on potential late radiation-induced toxicity and carcinogenesis have led to limiting indications in the dermatologist community. However, radiotherapy (RT) has undergone considerable developments, essentially including technological advances, to sculpt radiation delivery, with demonstration of the benefit either alone or after adding concomitant cytotoxic agents or targeted therapies. Although side effects due to high doses and/or the use of old RT techniques have been significantly decreased, the risk of atrophic scars, ulcerations or secondary cancers persist. In this systematic review, we aim to discuss indications for RT in melanomas with focus on new advances that may lead to rehabilitating this treatment option according to the tumor radiosensitivity and clinical benefit/risk ratio. Melanomas have been considered as radioresistant tumors for many years.

Outcomes of Proton Beam Radiotherapy for Large Non-Peripapillary Choroidal and Ciliary Body Melanoma at TRIUMF and the BC Cancer Agency

BACKGROUND AND PURPOSE

To report outcomes and toxicity after proton beam radiotherapy for non-peripapillary choroidal and ciliary body melanoma considered unsuitable for other eye-sparing therapies.

MATERIALS AND METHODS

An existing database of 77 patients with non-peripapillary tumors treated at TRIUMF, Canada, including patient, tumor, and treatment characteristics, was updated with ocular complications and follow-up status from chart reviews.

RESULTS

Most of the patients had large tumors: 61% were T3/T4 tumors (AJCC classification), while 48% were large by the Collaborative Ocular Melanoma Study classification. The median thickness was 7.1 mm, and the ciliary body was involved in 35%. After 5 and 10 years, the actuarial ocular tumor control rate was 85 and 85%, metastasis-free survival was 72 and 57%, overall survival was 77 and 63%, the enucleation rate was 22 and 22%, and complete blindness was found in 38 and 38%, respectively. On univariate analysis, patients with ciliary body involvement had significantly worse metastasis-free survival and overall survival rates compared to patients without ciliary body involvement (p < 0.001).

CONCLUSIONS

Proton therapy for large anteriorly located tumors resulted in acceptable ocular tumor control and survival rates. The risk of blindness and severe toxicity requiring enucleation was low, and a substantial proportion of patients maintained useful vision.

Diffusion-weighted magnetic resonance imaging for predicting and detecting the response of ocular melanoma to proton beam therapy: initial results

PURPOSE

The aim of this study was to investigate the utility of diffusion-weighted magnetic resonance (MR) imaging for prediction and early detection of response to proton beam therapy in ocular melanoma.

MATERIALS AND METHODS

Ten ocular melanoma patients treated with proton beam therapy were enrolled in the study. All patients underwent conventional MR imaging and diffusion-weighted imaging (DWI) before the start of therapy, and after 1, 3 and 6 months of therapy. Tumour volumes and apparent diffusion coefficient (ADC) values of ocular lesions were measured at each examination. Tumour volumes and mean ADC measurements of the four examination series were compared; correlation of ADC values and tumour regression was investigated.

RESULTS

Mean ADC value of ocular melanomas significantly increased as early as 3 months after therapy; tumour volume significantly decreased as early as 6 months after therapy. The ADC values of ocular melanomas before therapy significantly correlated with tumour regression.

CONCLUSIONS

DWI may provide an early surrogate biomarker for prediction and early detection of tumour response to eye-preserving therapies in ocular melanoma.