Radiation Treatment Affects Chromosome Testing in Uveal Melanoma

Radiation-Induced DNA Damage in Uveal Melanoma Is Influenced by Dose Delivery and Chromosome 3 Status

Purpose

The purpose of this study was to analyze the extent of DNA breaks in primary uveal melanoma (UM) with regard to radiotherapy dose delivery (single-dose versus fractionated) and monosomy 3 status.

Methods

A total of 54 patients with UM were included. Stereotactic radiotherapy (SRT) was performed in 23 patients, with 8 undergoing single-dose SRT (sdSRT) treatment and 15 receiving fractionated SRT (fSRT). DNA breaks in the enucleated or endoresected tumors were visualized by a TUNEL assay and quantified by measuring the TUNEL-positive area. Protein expression was analyzed by immunohistochemistry. Co-detection of chromosome 3 with proteins was performed by immuno-fluorescent in situ hybridization.

Results

The amount of DNA breaks in the total irradiated group was increased by 2.7-fold (P < 0.001) compared to non-irradiated tissue. Tumors treated with fSRT were affected more severely, showing 2.1-fold more DNA damage (P = 0.007) compared to the cases after single (high) dose irradiation (sdSRT). Monosomy 3 tumors showed less DNA breaks compared to disomy 3 samples (P = 0.004). The presence of metastases after radiotherapy correlated with monosomy 3 and less DNA breaks compared to patients with non-metastatic cancer in the combined group with fSRT and sdSRT (P < 0.05).

Conclusions

Fractionated irradiation led to more DNA damage than single-dose treatment in primary UM. As tumors with monosomy 3 showed less DNA breaks than those with disomy 3, this may indicate that they are less radiosensitive, which may influence the efficacy of irradiation.

BRCA-associated protein1 (BAP1) immunohistochemical stain reliability in postbrachytherapy uveal melanoma enucleation specimens

PURPOSE

The BRCA-associated protein1 (BAP1) immunohistochemical (IHC) stain has emerged as a powerful and inexpensive prognostic tool in uveal melanoma (UM), correlating with UM genetics and outcome. The data on the reliability of BAP1 immunohistochemistry in previously irradiated UM is scant. We aim to assess BAP1 IHC in post-Iodine-125 plaque brachytherapy-treated UM-enucleated eyes.

METHODS

In a case-control study, the medical records of all patients who underwent enucleation for UM at a major Ocular Oncology Service from December 1 st , 2007 to December 31 st , 2014 were reviewed. All cases with either chromosome 3 (ch3) status or sufficient follow-up (>5 years or metastasis) were selected. Nuclear BAP1 (nBAP1) immunoreactivity was interpreted as intact (positive in >90% of nuclei), lost (positive in <5% of nuclei), or heterogeneous (positive in 5-90% of nuclei). Retina and intratumoral blood vessels served as internal positive controls.

RESULTS

A comparison of 34 postbrachytherapy UM secondary-enucleated eyes with 47 nonbrachytherapy primary enucleated controls revealed no significant difference with respect to nBAP1 IHC (lost in 41% vs 51%, P = 0.19), ch3 status (ch3 monosomy in 59% vs 60%, P = 0.48), and outcome (metastatic disease in 44% vs 47%, P = 0.8). Association of nBAP1 IHC with ch3 status and outcome [intact nBAP1/(ch3 disomy and/or no metastasis) and lost nBAP1 (ch3 monosomy and/or metastasis)] in post-brachytherapy UM was significantly lower when compared with non-brachytherapy tumors [21/30 (70%) vs 41/44 (93%), P = 0.004*].

CONCLUSION

Although nBAP1 IHC stain is a strong prognostic tool in UM, its association with ch3 status, and outcome in postbrachytherapy UM was significantly lower compared with nonbrachytherapy tumors due to pitfalls in the interpretation of nBAP1 immunoreactivity in irradiated UM. This test should be used judiciously in the prognostication of postbrachytherapy-enucleated UM.

Need for a Dedicated Ophthalmic Malignancy Clinico-Biological Biobank: The Nice Ocular MAlignancy (NOMA) Biobank

Ophthalmic malignancies include various rare neoplasms involving the conjunctiva, the uvea, or the periocular area. These tumors are characterized by their scarcity as well as their histological, and sometimes genetic, diversity. Uveal melanoma (UM) is the most common primary intraocular malignancy. UM raises three main challenges highlighting the specificity of ophthalmic malignancies. First, UM is a very rare malignancy with an estimated incidence of 6 cases per million inhabitants. Second, tissue biopsy is not routinely recommended due to the risk of extraocular dissemination. Third, UM is an aggressive cancer because it is estimated that about 50% of patients will experience metastatic spread without any curative treatment available at this stage. These challenges better explain the two main objectives in the creation of a dedicated UM biobank. First, collecting UM samples is essential due to tissue scarcity. Second, large-scale translational research programs based on stored human samples will help to better determine UM pathogenesis with the aim of identifying new biomarkers, allowing for early diagnosis and new targeted treatment modalities. Other periocular malignancies, such as conjunctival melanomas or orbital malignancies, also raise specific concerns. In this context, the number of biobanks worldwide dedicated to ocular malignancies is very limited. The aims of this article were (i) to describe the specific challenges raised by a dedicated ocular malignancy biobank, (ii) to report our experience in setting up such a biobank, and (iii) to discuss future perspectives in this field.

Choroidal biopsies; a review and optimised approach

The majority of choroidal tumours are diagnosed accurately with clinical examination and the additional data obtained from non-invasive imaging techniques. Choroidal biopsies may be undertaken for diagnostic clarity in cases such as small melanocytic or indeterminate lesions, identifying the primary tumour in the case of choroidal metastases or the subclassification of rarer conditions such as uveal lymphoma. There is however an increasing use of biopsy techniques for prognostication in uveal melanoma. This review explores the main indications and surgical techniques for tumour acquisition, and the optimised approach utilised by the current authors to improve successful yield for histological and genetic analysis.

Chromosome 3 and 8q aberrations in Uveal Melanoma show greater impact on survival in patients with light iris versus dark iris color

PURPOSE

Individuals with gray, blue, or green iris have a higher chance of developing uveal melanoma (UM) than those with brown eyes. We wondered whether iris pigmentation might not only be related to predisposition to UM, but also to its behavior and therefore compared clinical, histopathologic, and genetic characteristics of UM between eyes with different iris colors.

DESIGN

We determined iris color in a large cohort of patients who had undergone an enucleation for UM. Clinical and histopathological tumor characteristics, chromosome status, and survival were compared between three groups, based on iris color.

PARTICIPANTS

412 patients with choroidal/ciliary body UM, who had undergone primary enucleation at the Leiden University Medical Center (LUMC), Leiden, The Netherlands, between 1993 and 2019, divided into three groups, based on iris color (gray/blue, green/hazel, and brown). Validation cohort: 934 choroidal/ciliary body UM patients treated at Wills Eye Hospital (WEH), Philadelphia, United States.

METHODS

Comparison of clinical, histopathologic, and genetic characteristics of UM in patients with different iris colors.

MAIN OUTCOME MEASURES

Melanoma-related survival in UM patients, divided over three iris color groups, in relation to the tumor's chromosome 3 and 8q status.

RESULTS

Moderate and heavy tumor pigmentation was especially seen in eyes with brown iris (p < 0.001). Survival did not differ between patients with different iris colors (p = 0.28). However, in patients with a light iris, copy number changes in chromosome 3 and 8q had a greater influence on survival than in patients with a dark iris. Similarly, chromosome 3 and chromosome 8q status affected survival more among patients with lightly-pigmented tumors than in patients with heavily-pigmented tumors. The WEH cohort similarly showed a greater influence of chromosome aberrations in light-eyed individuals.

CONCLUSIONS

While iris color by itself did not relate to survival of UM patients, chromosome 3 and 8q aberrations had a much larger influence on survival in patients with light iris compared to those with brown iris. This suggests a synergistic effect of iris pigmentation and chromosome status in the regulation of oncogenic behavior of UM. Iris color should be taken into consideration when calculating the risk for developing metastases.

Adjuvant External Beam Radiotherapy Following Enucleation of Eyes With Extraocular Extension From Uveal Melanoma

PURPOSE

To report local disease control and all-cause mortality in patients with extraocular extension (EOE) of uveal melanoma undergoing enucleation followed by observation or external beam radiotherapy (EBRT).

METHODS

Charts of patients enucleated between January 1, 1997 and December 31, 2019, with histopathological evidence of EOE of uveal melanoma were reviewed.

RESULTS

The cohort comprised 51 patients with a mean age of 67 ± 15 years, 22 (43%) of whom underwent adjuvant postenucleation EBRT. Risk factors for metastasis included presence of epithelioid cells (29/45; 88%), closed loops (20/43; 47%), monosomy 3 (16/25; 64%), and gain of 8q (20/22; 91%). Patients undergoing EBRT had more extensive EOE (median: 5.1 mm vs. 2.6 mm, p = 0.008) and surgical excision was less likely to be histologically complete (2/20; 10% vs. 14/25; 56%, p = 0.002). Local side effects following EBRT were seen in 64% (14/22). At latest follow up, 59% of patients (30/51) were alive, with a median follow up of 1.8 years (interquartile range: 2.9; range: 0.1-6.5]. By Kaplan-Meier survival analysis, the 5- and 10-year overall survival rates were 56% and 12%, respectively. There was no difference in all-cause mortality between those receiving adjuvant EBRT and those who were observed (log rank, p = 0.273). No cases of orbital recurrence were documented.

CONCLUSIONS

Orbital EBRT causes significant morbidity. Cases with relatively small EOE undergoing enucleation can be safely observed, without adjuvant EBRT. Multicenter studies are required to better assess the role of EBRT when EOE is more extensive.

Five Decades of Enucleations for Uveal Melanoma in One Center: More Tumors with High Risk Factors, No Improvement in Survival over Time

Background

In order to improve medical care for uveal melanoma (UM) patients, we need to monitor disease and survival to guide our research efforts. We analyzed the data of UM patients who underwent an enucleation at the Leiden University Medical Center over the last five decades and investigated trends in patient and tumor characteristics and survival.

Methods

Data were collected from charts and pathology reports from all patients who underwent an enucleation for UM between 1973 and 2019 (n = 1,212), of which 1,066 were primary enucleations; data were analyzed according to five time periods: 1973-1979 (n = 209), 1980-1989 (n = 148), 1990-1999 (n = 174), 2000-2009 (n = 280), and 2010-2019 (n = 401).

Results

Over time, mean patient age at the time of enucleation for UM increased from 54.9 to 64.7 years (p < 0.001), more tumors showed histopathological involvement of the ciliary body (p < 0.001), and were classified in a high TNM/AJCC class (p < 0.001). Overall, the 5- and 10-year UM-related survival rates were 0.68 and 0.59, respectively. Over time, survival showed no change in patients with tumors in AJCC stages I or III, with recently a slightly worse survival in stage II UM (p = 0.02).

Conclusion

Between 1973 and 2019, we found similar rates of UM-related survival following enucleation, although we noticed a strong increase in more unfavorable patient and tumor characteristics over time, such as an older age and larger tumor size. The lack of improvement indicates that more research should take place to develop adjuvant treatments to prevent metastases and efficient treatments once metastases develop.

A 45-year experience of uveal melanoma in Taiwan: Verification of American Joint Committee on Cancer staging system and prognostic factors

BACKGROUND/PURPOSE

To verify the staging system of the American Joint Committee on Cancer (AJCC) 8th edition for uveal melanoma, and to propose the prognostic factors of uveal melanoma by a 45-year cohort study.

METHODS

We collected patients who underwent operation with pathological proof from 1973 to 2017. The demographic data including gender, age, laterality, metastatic pattern, and histopathology type were recorded. The predictability for survival and monotonicity of gradients of the AJCC 8th edition were evaluated. The prognostic factors for survival were analyzed by univariate and multivariate analysis.

RESULTS

A total of 72 patients were collected. The median age was 55 year-old (range 24-100). No specific gender predilection was revealed in our study. About 75.9% of metastases events happened in the first five-year of follow-up, and hepatic involvement was the most common. By the AJCC 8th edition, the distribution for stage I: II: III was 8 (11.1%), 37 (51.4%), and 27 (37.5%). The prognostic staging groups manifested fair predictability and monotonicity of gradients for survival outcome. The tumors with epithelioid cell type and ciliary body involvements had higher tumor-related mortality.

CONCLUSION

The AJCC 8th edition prognostic staging groups for outcome prediction was validated. Periodic screening for metastases should be more frequent in the first five-year follow-up. The tumors with epithelioid cell pattern and ciliary body involvements were at risk of higher tumor-related mortality in Taiwanese patients.

Prognostic Factors Five Years After Enucleation for Uveal Melanoma

Purpose

A subgroup of uveal melanoma (UM) gives rise to metastases at a late stage. Our objective was to identify patient and tumor characteristics that are associated with UM-related death in patients who survived 5 years following enucleation.

Methods

A retrospective analysis was performed in 583 primary UM cases, enucleated at the Leiden University Medical Center between 1983 and 2013. Univariable and multivariable Cox regression analyses were performed in the total cohort and separately in those surviving more than 5 years (n = 297).

Results

In the total cohort, the median age was 62.6 years, and the median tumor diameter was 12.0 mm. Monosomy 3 was detected in 53% of cases and gain of 8q in 47%. In the cohort surviving 5 years, the median age was 59.5 years, and the median tumor diameter was 11.0 mm. Monosomy 3 and gain of 8q were detected in 33% and 31% of cases, respectively. In the total cohort, male gender (P = 0.03), tumor diameter (P < 0.001), mitotic count (P < 0.001), extravascular matrix loops (P = 0.03), extraocular growth (P < 0.001), and gain of 8q (P < 0.001) were independently associated with UM-related death. In patients surviving 5 years after enucleation, univariable analysis revealed that age (P = 0.03), tumor diameter (P < 0.001), monosomy 3 (P = 0.04), and 8q gain (P = 0.003) were associated with subsequent UM-related death. Using a multivariable analysis, only male gender (P = 0.03) and gain of 8q (P = 0.01) remained significant.

Conclusions

Predictors of UM-related death change over time. Among UM patients who survived the initial 5 years following enucleation, male gender and chromosome 8q status were the remaining factors related to UM-related death later on.

Elevated VEGF-A & PLGF concentration in aqueous humor of patients with uveal melanoma following Iodine-125 plaque radiotherapy

AIM

To measure the concentration of vascular endothelial growth factor-A (VEGF-A), and placental growth factor (PLGF) in aqueous humor of uveal melanoma patients before and after Iodine-125 plaque therapy (IPT), determine the postoperative fluctuation and evaluate associated factors in vivo.

METHODS

Participants were 18 Chinese patients with uveal melanoma who were elected to IPT. Undiluted aqueous humor samples were collected at Iodine plaque implant and removal time, then stored immediately at -80°C until assayed. The concentration of VEGF-A, PLGF and other 7 cytokines comprising interleukin-2 (IL-2), IL-8, IL-10, interferon (IFN)-γ, programmed death (PD)-1, transforming growth factor (TGF)-β1 and insulin-like growth factor (IGF)-1 in aqueous humor was measured using Raybiotech immunoassay kit, a high throughput strategy. The VEGF-A and PLGF levels were compared across preoperation and postoperation subgroups, as well as those of other 7 interleukins. Correlation and grouped analyses were conducted to determine the independent effects of clinical parameters and other cytokines on VEGF-A and PLGF concentration or fluctuation. This study set a self-control design.

RESULTS

VEGF-A (P=0.038) and PLGF (P=0.026) were the only two increased cytokines after IPT. Preoperative and postoperative level of VEGF-A and PLGF (r=0.575, P=0.013; r=0.987, P<0.001) correlated with each other significantly. Level of VEGF-A (r=0.626, P=0.005; r=0.588, P=0.01) and PLGF (r=0.616, P=0.007; r=0.588, P=0.01) had positive correlation with tumor thickness consistently. Elevated VEGF-A or PLGF level were strong predictive factors of each other (P=0.007, OR=60.0). The elevated VEGF-A group showed a higher postoperative level of IFN-γ (P=0.005), IL-2 (P<0.001) and IL-10 (P=0.004) in aqueous humor. When the elevated PLGF group got similar results that a higher postoperative level of IFN-γ (P=0.007), IL-2 (P<0.001) and IL-10 (P=0.013) in aqueous humor.

CONCLUSION

This study reveals that VEGF-A and PLGF in aqueous humor significantly increased with tumor thickness and radiation process in uveal melanoma patients. VEGF-A and PLGF may be crucial in uveal melanoma genesis and radiotherapy reactions. Immune mediators comprised IFN-γ, IL-2 and IL-10 could play roles in the link between inflammation and angiogenesis in uveal melanoma when exposed to radiotherapy.

Effects of plaque brachytherapy and proton beam radiotherapy on prognostic testing: a comparison of uveal melanoma genotyped by microsatellite analysis

Background/aims

Proton beam radiotherapy and plaque brachytherapy are commonly applied in primary uveal melanoma (UM); however, their effect on chromosome 3 classification of UM by microsatellite analysis (MSA) for prognostication purposes is unknown, where the tumour is sampled post-irradiation. This study examined the prognostic accuracy of genotyping UM biopsied before or after administration of radiotherapy, by MSA.

Methods

407 UM patients treated at the Liverpool Ocular Oncology Centre between January 2011 to December 2017, were genotyped for chromosome 3 by MSA; 172 and 176 primary UM were sampled prior to and post irradiation, respectively.

Results

Genotyping by MSA was successful in 396/407 (97%) of UM samples (196 males, 211 females; median age of 61 years (range 12 to 93) at primary treatment). There was no demonstrable association between a failure of MSA to produce a chromosome 3 classification and whether radiation was performed pre-biopsy or post-biopsy with an OR of 0.96 (95% CI 0.30 to 3.00, p=0.94). There was no evidence of association (measured as HRs) between risk of metastatic death and sampling of a primary UM before administration of radiotherapy (HR 1.1 (0.49 to 2.50), p=0.81). Monosomy 3 (HR 12.0 (4.1 to 35.0), p<0.001) was significantly associated with increased risk of metastatic death.

Conclusions and relevance

This study revealed that successful genotyping of UM using MSA is possible, irrespective of irradiation status. Moreover, we found no evidence that biopsy prior to radiotherapy increases metastatic mortality.

Uveal Melanoma Biopsy: A Review

Intraocular tumor diagnosis is based on clinical findings supported by additional imaging tools, such as ultrasound, optical coherence tomography and angiographic techniques, usually without the need for invasive procedures or tissue sampling. Despite improvements in the local treatment of uveal melanoma (UM), the prevention and treatment of the metastatic disease remain unsolved, and nearly 50% of patients develop liver metastasis. The current model suggests that tumor cells have already spread by the time of diagnosis, remaining dormant until there are favorable conditions. Tumor sampling procedures at the time of primary tumor diagnosis/treatment are therefore now commonly performed, usually not to confirm the diagnosis of UM, but to obtain a tissue sample for prognostication, to assess patient's specific metastatic risk. Moreover, several studies are ongoing to identify genes specific to UM tumorigenesis, leading to several potential targeted therapeutic strategies. Genetic information can also influence the surveillance timing and metastatic screening type of patients affected by UM. In spite of the widespread use of biopsies in general surgical practice, in ophthalmic oncology the indications and contraindications for tumor biopsy continue to be under debate. The purpose of this review paper is to critically evaluate the role of uveal melanoma biopsy in ophthalmic oncology.

Genetic prognostication in uveal melanoma

Uveal melanoma (UM) is a rare tumour with a high propensity to metastasize. Although no effective treatment for metastases yet exists, prognostication in UM is relevant for patient counselling, planning of follow-up and stratification in clinical trials. Besides conventional clinicopathologic characteristics, genetic tumour features with prognostic significance have been identified. Non-random chromosome aberrations such as monosomy 3 and gain of chromosome 8q are strongly correlated with metastatic risk, while gain of chromosome 6p indicates a low risk. Recently, mutations in genes such as BAP1, SF3B1 and EIF1AX have been shown to be related to patient outcome. Genetics of UM is a rapidly advancing field, which not only contributes to the understanding of the pathogenesis of this cancer, but also results in further refinement of prognostication. Concomitantly, advances have been made in the use of genetic tests. New methods for genetic typing of UM have been developed. Despite the considerable progress made recently, many questions remain, such as those relating to the reliability of prognostic genetic tests, and the use of biopsied or previously irradiated tumour tissue for prognostication by genetic testing. In this article, we review genetic prognostic indicators in UM, also comparing available genetic tests, addressing the clinical application of genetic prognostication and discussing future perspectives for improving genetic prognostication in UM.

MOLECULAR PROGNOSTICS FOR UVEAL MELANOMA

PURPOSE

To review laboratory methods, currently available commercial tests, caveats and clinical tips regarding prognostic analysis of uveal melanoma tissue.

METHODS

A review of the literature was performed focused on the genetic abnormalities found in uveal melanoma cells, their correlation to the development of metastases, the validity of various laboratory approaches in their detection, and the existing commercially available tests for uveal melanoma prognostication.

RESULTS

Numerous laboratory methods exist for analyzing genetic material obtained from uveal melanoma cells. Older tests have been gradually replaced with contemporary methods that are simpler with greater accuracy. Two commercially available assays exist which have not been directly compared-a gene expression profiling test has been validated directly through a large, prospective multicenter study and a DNA-based test which uses laboratory methods supported by extensive historical data.

CONCLUSION

There are myriad laboratory methods for prognostic analysis of uveal melanoma tissue. These tests were historically only available to those with access to an outfitted laboratory. Newer commercially available assays have increased the accessibility of prognostic biopsy for uveal melanoma. The various caveats that exist when considering and performing prognostic biopsy of uveal melanoma are discussed.

Brachytherapy for patients with uveal melanoma: historical perspectives and future treatment directions

Surgical management with enucleation was the primary treatment for uveal melanoma (UM) for over 100 years. The Collaborative Ocular Melanoma Study confirmed in 2001 that globe-preserving episcleral brachytherapy for UM was safe and effective, demonstrating no survival difference with enucleation. Today, brachytherapy is the most common form of radiotherapy for UM. We review the history of brachytherapy in the treatment of UM and the evolution of the procedure to incorporate fine-needle-aspiration biopsy techniques with DNA-and RNA-based genetic prognostic testing.

New concepts in the molecular understanding of uveal melanoma

PURPOSE OF REVIEW

Uveal melanoma is the most common primary intraocular malignancy, and its metastases are deadly. Significant work has been done to elucidate the molecular framework that causes uveal melanoma development and metastasis. This review is intended to highlight the most recent breakthroughs in the molecular understanding of uveal melanoma.

RECENT FINDINGS

Monosomy of chromosome 3 and class 2 gene-expression profile are well-known indicators of melanoma metastasis. However, some patients with disomy 3 and class 1 gene expression profiling (GEP) still develop metastasis. Disomy 3 tumors may be further classified based upon the presence of an SF3B1 mutation. The role of SF3B1 gene is unclear at this time but may be related to the development of late metastases among disomy 3 uveal melanoma. Class 1 GEP tumors have recently been subdivided into class 1a and class 1b, with class 1b tumors carrying a slightly higher risk of metastasis. Among patients with either class 1 or class 2 GEP, the expression of preferentially expressed antigen in melanoma (PRAME) is an independent risk factor for the development of metastasis. Mutation of GNAQ is the most commonly observed mutation in uveal melanoma, regardless of chromosome 3 status or GEP class. Inhibitors or GNAQ may be targets for therapeutic intervention in uveal melanoma. MicroRNA molecules are small noncoding RNA molecules that have been recently demonstrated to function in RNA silencing and posttranscriptional regulation of gene expression. These molecules may play a role in the development of uveal melanoma metastasis.

SUMMARY

New findings such as the presence or absence of PRAME, mutations in the SF3B1 gene and microRNA dysregulation have added new layers to our understanding of uveal melanoma. These new concepts will enhance our ability to prognosticate tumor metastasis and may provide targets for therapeutic intervention.

Genetic evolution of uveal melanoma guides the development of an inflammatory microenvironment

Uveal melanoma (UM) is characterized by a number of genetic aberrations that follow a certain chronology and are tightly linked to tumor recurrence and survival. Loss of chromosome 3, bi-allelic loss of BAP1 expression, and gain in chromosome 8q have been associated with metastasis formation and death, while loss of chromosome 3 has been associated with the influx of macrophages and T cells. We used a set of genetically-classified UM to study immune infiltration in the context of their genetic evolution. We show in two independent cohorts that lack of BAP1 expression is associated with an increased density of CD3⁺ T cells and CD8⁺ T cells. The presence of extra copies of chromosome 8q in disomy 3 tumors with a normal BAP1 expression is associated with an increased influx of macrophages (but not T cells). Therefore, we propose that the genetic evolution of UM is associated with changes in the inflammatory phenotype. Early changes resulting in gain of chromosome 8q may activate macrophage infiltration, while sequential loss of BAP1 expression seems to drive T cell infiltration in UM.

Clinical Performance and Management Outcomes with the DecisionDx-UM Gene Expression Profile Test in a Prospective Multicenter Study

Uveal melanoma management is challenging due to its metastatic propensity. DecisionDx-UM is a prospectively validated molecular test that interrogates primary tumor biology to provide objective information about metastatic potential that can be used in determining appropriate patient care. To evaluate the continued clinical validity and utility of DecisionDx-UM, beginning March 2010, 70 patients were enrolled in a prospective, multicenter, IRB-approved study to document patient management differences and clinical outcomes associated with low-risk Class 1 and high-risk Class 2 results indicated by DecisionDx-UM testing. Thirty-seven patients in the prospective study were Class 1 and 33 were Class 2. Class 1 patients had 100% 3-year metastasis-free survival compared to 63% for Class 2 (log rank test p = 0.003) with 27.3 median follow-up months in this interim analysis. Class 2 patients received significantly higher-intensity monitoring and more oncology/clinical trial referrals compared to Class 1 patients (Fisher's exact test p = 2.1 × 10(-13) and p = 0.04, resp.). The results of this study provide additional, prospective evidence in an independent cohort of patients that Class 1 and Class 2 patients are managed according to the differential metastatic risk indicated by DecisionDx-UM. The trial is registered with Clinical Application of DecisionDx-UM Gene Expression Assay Results (NCT02376920).