Linear Accelerator Stereotactic Radiosurgery in Intraocular Malignant Melanoma

Special Article - Stereotactic Body Radiotherapy

Austin J Radiat Oncol & Cancer. 2015;1(2): 1008.

Linear Accelerator Stereotactic Radiosurgery in Intraocular Malignant Melanoma

Alena Furdová¹*, Miron Sramka², Martin Chorvath² and Gabriel Kralik³

¹Department of Ophthalmology, Comenius University, Slovak Republic

²Department of Stereotactic Radiosurgery, St. Elisabeth Cancer Inst. and St. Elisabeth University College of Health and Social Work, Slovak Republic

³Faculty of Medicine of the Slovak Medical University, Slovak Republic

*Corresponding author: Alena Furdová, Department of Ophthalmology, Medical School, Comenius University Pažítkova 4, 821 03 Bratislava, Slovak Republic

Received: May 05, 2015; Accepted: May 12, 2015; Published: May 13, 2015


Objective: Linear accelerator based stereotactic radiosurgery of intraocular malignant melanoma is a method to treat uveal melanoma (ciliary body and choroid).

Material and Methods: Retrospective clinic-based study of patients with posterior uveal melanoma in stage T1 - T3 who underwent stereotactic radiosurgery at linear accelerator in period 2001- 2013.

Results: In group of 123 patients with posterior uveal melanoma treated with one day session stereotactic radiosurgery the median tumor volume was 0.6 cm3 (0.2 - 1.0 cm3). Patient age ranged from 25 to 82 years with a median of 55 years. The therapeutic dose applied to melanoma was 35.0 Gy, median maximal dose applied was 49.0 Gy (37.0 - 54.0 Gy). In the group of small tumors the volume regression was verified in 6 months and 12 months interval after the therapy by ultrasound and MRI (there was no presence of increase of the elevation). In 24 months interval the tumor regression was present in 25 cases from 35 cases (71.4 %). Tumor local control was successful in 95 % of patients in 2 years interval after stereotactic radiosurgery and in 85 % of patients in 5 years interval after stereotactic radiosurgery. Secondary enucleation due secondary glaucoma was necessary in 14 patients (11.4 %) in 3 to 5 year interval after irradiation.

Conclusion: One step LINAC based stereotactic radiosurgery with a single dose 35.0 Gy is treatment option to treat T1 to T3 stage intraocular melanoma.

Keywords: Intraocular tumors; Uveal melanoma; Linear accelerator radiosurgery


Uveal melanoma is relatively rare type of cancer, but the most common and most aggressive type of intraocular tumor in adults. The incidence of intraocular tumors varies from 0.2 to 1.0. According to the Slovak National Cancer Registry the incidence in Slovakia is 0.2 to 0.6 / 100 000 inhabitants. The recorded data from Slovak regions correspond with the data reported from other countries and regions of Europe [1].

Over 50 % of patients with uveal melanoma die within 15 years after the therapy – either radical surgery (enucleation), or other therapeutical methods [2]. Age and volume (size) of the tumor have been shown to be prognostic indicators following therapy for posterior uveal melanoma. Modern diagnostic tools, ophthalmological examination, computed tomography and magnetic resonance have led to significant advances in the ability to diagnose primary uveal melanoma. Over the past three decades diagnostic methods have improved and radiotherapy (external beam, charged particle or brachytherapy) has become the preferred treatment for most patients with uveal melanoma. The desire to improve survival and preserve vision in patients with uveal melanoma has stimulated the development of alternative therapies. Different radiation modalities are currently in use in treatment of posterior uveal melanoma. One of the methods of “conservative” approach is the Stereotactic Radiosurgery (SRS) by linear accelerator.

Stereotactic radiation therapy and gamma-knife radiosurgery also provide good local control, with survival rates comparable with other treatments.

SRS of extracerebral lesions like uveal melanoma has been invented in the last two decades and is an alternative treatment for middle and large posterior choroidal melanoma. With plaque radiotherapy, eye salvage is achieved, and, particularly for cases in which the tumor is located away from the optic disc or macula, useful vision can be retained after treatment. The single irradiation of the intraocular tumor by linear accelerator therapy itself is a new approach – it has been shown to achieve ultrasonic tumor regression in a similar fashion to brachytherapy.

In this study we assess the treatment of posterior uveal melanoma by one-day session of LINAC based stereotactic radiosurgery.


A retrospective analysis was undertaken for patients with posterior uveal melanoma (tumor arising from ciliary body or choroid) in stage T1 to T3 who underwent stereotactic radiosurgery at C LINAC in period 2001- 2013. Patients were not randomized either to radical (enucleation) or to “conservative” procedure, but the treatment was determined exclusively on a case-by-case basis. Tumor stage, volume, maximum elevation, localization presence of secondary retinal detachment, general status, age, gender, the functional tests (visual acuity, perimeter, ultrasound) were taken into consideration. The patient was actively involved in the decision on the therapeutic procedure after explaining possible postoperative complications.

Before stereotactic irradiation immobilization of the affected eye was achieved by mechanical fixation to the stereotactic Leibinger frame. Sutures were placed under 4 direct extraocular muscles through conjunctiva and through the lids. The stereotactic frame was fixed to the head and the sutures were tied to the stereotactic frame (Figure 1). The patient underwent CT and MRI examination with the fixed eye to the frame. Stereotactic radiosurgery was perfomed by oned – day session on linear accelerator Model LINAC C 600 C/D Varian with 6 MeV X. The stereotactic treatment planning after fusion of CT and MRI was optimized according to the critical structures - lens, optic nerve, also lens and optic nerve at the contralateral side, chiasm (Figure 2a and 2b). The best stereotactic radiosurgical planning scheme was applied for therapy at linear accelerator. Tumor volume calculation was based on the ROI (region of interest) of the tumor and 3D reconstruction was done. The planned therapeutic dose into the tumor mass was 35.0 Gy by 99 % of DVH (dose volume histogram).