Clinical Experience of Stereotactic Radiosurgery at a Linear Accelerator for Intraocular Melanoma Combined with Iridociliary Tumor Resection: A Case Report

Introduction: The treatment of iridociliary and choroidal melanoma relies on the patient’s systemic health, tumor size, location, related features, state of the opposing eye, and personal preferences. The two categories are radiation and surgical techniques. Transpupillary thermotherapy, plaque radiotherapy, charged particle irradiation, local resection, enucleation, orbital exenteration, and experimental nanoparticle therapy are all options for treating choroidal melanoma. Case Presentation: The method that entails creating a partial thickness circular, rectangular, or polyhedral scleral flap in the region covering the tumor after removing a portion of the extraocular muscles is the most popular method for local excision in choroidal or choroidal-ciliary body cancers. We discuss our experience treating iridociliary melanoma using block excision and stereotactic irradiation on a linear accelerator with TD 20.0 Gy. Conclusion: One of the treatment modalities is the combined treatment approach using stereotactic irradiation and tumor resection, and our results 1 year after therapy are comparable to the rates of local control and anatomic eye preservation to those achieved in studies of comparable uveal melanoma treatment modalities

KIT Expression Is Regulated by DNA Methylation in Uveal Melanoma Tumors

Uveal melanoma (UM) is an ocular tumor with a dismal prognosis. Despite the availability of precise molecular and cytogenetic techniques, clinicopathologic features with limited accuracy are widely used to predict metastatic potential. In 51 UM tissues, we assessed a correlation between the expression of nine proteins evaluated by immunohistochemistry (IHC) (Melan-A, S100, HMB45, Cyclin D1, Ki-67, p53, KIT, BCL2, and AIFM1) and the presence of UM-specific chromosomal rearrangements measured by multiplex ligation-dependent probe amplification (MLPA), to find IHC markers with increased prognostic information. Furthermore, mRNA expression and DNA methylation values were extracted from the whole-genome data, achieved by analyzing 22 fresh frozen UM tissues. KIT positivity was associated with monosomy 3, increasing the risk of poor prognosis more than 17-fold (95% CI 1.53–198.69, p = 0.021). A strong negative correlation was identified between mRNA expression and DNA methylation values for 12 of 20 analyzed positions, five located in regulatory regions of the KIT gene (r = −0.658, p = 0.001; r = −0.662, p = 0.001; r = −0.816; p < 0.001; r = −0.689, p = 0.001; r = −0.809, p < 0.001, respectively). DNA methylation β values were also inversely associated with KIT protein expression (p = 0.001; p = 0.001; p = 0.015; p = 0.025; p = 0.002). Our findings, showing epigenetic deregulation of KIT expression, may contribute to understanding the past failure to therapeutically target KIT in UM