Prospective evaluation of risk-appropriate management of uveal melanoma patients informed by gene expression profiling

COMPREHENSIVE MOLECULAR PROFILING OF UVEAL MELANOMA EVALUATED WITH GENE EXPRESSION PROFILING, PREFERENTIALLY EXPRESSED ANTIGEN IN MELANOMA EXPRESSION, AND NEXT-GENERATION SEQUENCING

PURPOSE

To determine the association between gene-expression profiling (GEP), next-generation sequencing (NGS), preferentially expressed antigen in melanoma (PRAME) features, and metastatic risk in patients with uveal melanoma (UM).

METHODS

A retrospective analysis of patients with UM treated by brachytherapy or enucleation by a single ocular oncologist was conducted from November 2020 and July 2022. Clinicopathologic features, patient outcomes, GEP classification, NGS, and PRAME results were recorded.

RESULTS

Comprehensive GEP, PRAME, and NGS testing was performed on 135 UMs. The presence of eukaryotic translation initiation factor 1A, X-chromosomal and splicing factor 3B subunit 1 mutations was significantly associated with GEP class 1A and GEP class 1B, respectively. The presence of BRCA- associated protein-1 mutation was significantly associated with GEP class 2. The average largest basal diameter for tumors with eukaryotic translation initiation factor 1A, X-chromosomal mutations was significantly smaller than those with splicing factor 3B subunit 1 mutations and BRCA1-associated protein-1 mutations. Class 2 tumors metastasized sooner than GEP class 1 tumors. Tumors with splicing factor 3B subunit 1 and/or BRCA1-associated protein-1 mutations metastasized sooner compared with tumors that had either no driver mutation or no mutations at all. Tumors with splicing factor 3B subunit 1 did not have a significantly different time to metastasis compared with tumors with BRCA1-associated protein-1 (P value = 0.97). Forty tumors (30%) were PRAME positive, and the remaining 95 tumors (70%) were PRAME negative. Tumors with PRAME-positive status did not have a significantly different time to metastasis compared with tumors without PRAME-positive status (P value = 0.11).

CONCLUSION

GEP, NGS, and PRAME expression analysis help determine different levels of metastatic risk in UM. Although other prognostic tests exist, the following study reports on the use of NGS for metastatic prognostication in UM. However, limitations of NGS exist, especially with small lesions that are technically difficult to biopsy.

Impact of gene expression profiling on diagnosis and survival after metastasis in patients with uveal melanoma

Surveillance frequency for metastasis is guided by gene expression profiling (GEP). This study evaluated the effect of GEP on time to diagnosis of metastasis, subsequent treatment and survival. A retrospective study was conducted of 110 uveal melanoma patients with GEP (DecisionDx-UM, Castle Biosciences, Friendswood, Texas, USA) and 110 American Joint Committee on Cancer-matched controls. Surveillance testing and treatment for metastasis were compared between the two groups and by GEP class. Rates of metastasis, overall survival and melanoma-related mortality were calculated using Kaplan-Meier estimates. Baseline characteristics and follow-up time were balanced in the two groups. Patients' GEP classification was 1A in 41%, 1B in 25.5% and 2 in 33.6%. Metastasis was diagnosed in 26.4% ( n  = 29) in the GEP group and 23.6% ( n  = 26) in the no GEP group ( P  = 0.75). Median time to metastasis was 30.5 and 22.3 months in the GEP and no GEP groups, respectively ( P  = 0.44). Median months to metastasis were 34.7, 75.8 and 26.1 in class 1A, 1B and 2 patients, respectively ( P  = 0.28). Disease-specific 5-year survival rates were 89.4% [95% confidence interval (CI): 81.0-94.2%] and 84.1% (95% CI: 74.9-90.1%) in the GEP and no GEP groups respectively ( P  = 0.49). Median time to death from metastasis was 10.1 months in the GEP group and 8.5 months in the no GEP group ( P  = 0.40). There were no significant differences in time to metastasis diagnosis and survival outcomes in patients with and without GEP. To realize the full benefit of GEP, more sensitive techniques for detection of metastasis and adjuvant therapies are required.

Zebrafish Patient-Derived Xenograft Model as a Preclinical Platform for Uveal Melanoma Drug Discovery

Uveal melanoma (UM) is a rare malignant cancer of the eye, with up to 50% of patients dying from metastasis, for which no effective treatment is available. Due to the rarity of the disease, there is a great need to harness the limited material available from primary tumors and metastases for advanced research and preclinical drug screening. We established a platform to isolate, preserve, and transiently recover viable tissues, followed by the generation of spheroid cultures derived from primary UM. All assessed tumor-derived samples formed spheroids in culture within 24 h and stained positive for melanocyte-specific markers, indicating the retention of their melanocytic origin. These short-lived spheroids were only maintained for the duration of the experiment (7 days) or re-established from frozen tumor tissue acquired from the same patient. Intravenous injection of fluorescently labeled UM cells derived from these spheroids into zebrafish yielded a reproducible metastatic phenotype and recapitulated molecular features of the disseminating UM. This approach allowed for the experimental replications required for reliable drug screening (at least 2 individual biological experiments, with n > 20). Drug treatments with navitoclax and everolimus validated the zebrafish patient-derived model as a versatile preclinical tool for screening anti-UM drugs and as a preclinical platform to predict personalized drug responses.

Treatment of metastatic uveal melanoma in 2022: improved treatment regimens and improved prognosis

PURPOSE OF REVIEW

Until recently, metastatic uveal melanoma was associated with essentially uniform fatality within months. However, recent developments in screening, improved understanding of the genetic underpinnings of metastatic disease, and pivotal medication approvals have improved the disease's rate of fatality.

RECENT FINDINGS

Routine implementation of genetic testing at the time of primary tumor treatment via gene expression profiling or chromosomal analysis has identified patients who are at high risk for metastatic disease. Enhanced screening with imaging directed at the liver and lungs has allowed for identification of early disease and lower tumor burden. Significant work on improved liver directed therapy along with systemic chemotherapy and immunotherapy has improved life expectancy. The first systemic immunotherapy specifically for metastatic uveal melanoma was approved this year. This medication, tebentafusp, is likely to improve life expectancy for all patients with metastatic melanoma assuming they have appropriate human leukocyte antigen (HLA) markers. Multiple clinical trials with novel immunotherapeutic agents are promising as well.

SUMMARY

The prognosis for patients with uveal melanoma is far better than ever before because of recent developments in the understanding and treatment of metastatic disease.

Uveal melanoma patient attitudes towards prognostic testing using gene expression profiling

Aim:

This study explored uveal melanoma patient experiences and regret following molecular prognostic testing using a 15-gene expression profile (GEP) test.

Materials & methods:

A retrospective, cross-sectional survey study was conducted through an online questionnaire capturing patient-reported experiences with prognostic biopsy/molecular testing.

Results:

Of 177 respondents, 159 (90%) wanted prognostic information at diagnosis. Most 15-GEP-tested patients who shared their results (99%) reported gaining value from testing, as did patients tested with other methods. Patients who received prognostic testing experienced lower decision regret than those who opted out. Decision regret did not differ based on GEP class.

Conclusion:

Most uveal melanoma patients desire prognostic testing and gain value from the GEP, independent of a high- or low-risk result.

Uveal melanoma is a rare but aggressive eye cancer, resulting in distant metastasis in nearly 50% of patients. Molecular prognostic testing is often employed to determine who is at high or low risk of developing metastatic disease. A prognostic 15-gene expression profiling (GEP) test is commonly used throughout the USA and parts of Canada. The goal of this survey was to assess patient experiences with the 15-GEP and other prognostic methods. Of the 177 patients who participated in the survey, the majority reported that they wanted prognostic information at the time of diagnosis. Of patients who underwent 15-GEP testing, nearly all reported gaining value from their test result, regardless of their individual risk profile. This study supports prior findings using other prognostic methods that patients prefer information about their risk of metastasis and reinforces the importance of discussing prognostic testing options with newly diagnosed uveal melanoma patients.

Metastatic uveal melanoma: The final frontier

Treatment of primary intraocular uveal melanoma has developed considerably, its driver genes are largely unraveled, and the ways to assess its risk for metastases are very precise, being based on an international staging system and genetic data. Unfortunately, the risk of distant metastases, which emerge in approximately one half of all patients, is unaltered. Metastases are the leading single cause of death after uveal melanoma is diagnosed, yet no consensus exists regarding surveillance, staging, and treatment of disseminated disease, and survival has not improved until recently. The final frontier in conquering uveal melanoma lies in solving these issues to cure metastatic disease. Most studies on metastatic uveal melanoma are small, uncontrolled, retrospective, and do not report staging. Meta-analyses confirm a median overall survival of 10-13 months, and a cure rate that approaches nil, although survival exceeding 5 years is possible, estimated 2% either with first-line treatment or with best supportive care. Hepatic ultrasonography and magnetic resonance imaging as surveillance methods have a sensitivity of 95-100% and 83-100%, respectively, to detect metastases without radiation hazard according to prevailing evidence, but computed tomography is necessary for staging. No blood-based tests additional to liver function tests are generally accepted. Three validated staging systems predict, each in defined situations, overall survival after metastasis. Their essential components include measures of tumor burden, liver function, and performance status or metastasis free interval. Age and gender may additionally influence survival. Exceptional mutational events in metastases may make them susceptible to checkpoint inhibitors. In a large meta-analysis, surgical treatment was associated with 6 months longer median overall survival as compared to conventional chemotherapy and, recently, tebentafusp as first-line treatment at the first interim analysis of a randomized phase III trial likewise provided a 6 months longer median overall survival compared to investigator's choice, mostly pembrolizumab; these treatments currently apply to selected patients. Promoting dormancy of micrometastases, harmonizing surveillance protocols, promoting staging, identifying predictive factors, initiating controlled clinical trials, and standardizing reporting will be critical steppingstones in reaching the final frontier of curing metastatic uveal melanoma.

Small Choroidal Melanoma: Correlation between Clinical Characteristics and Metastatic Potential

IMPORTANCE

Diagnosis of small choroidal melanoma is based upon clinical features and presence of factors predictive of local malignant growth. Prognostic biopsy quantifies risk of metastasis.

OBJECTIVE

The aim of this study is to explore relationship between clinical characteristics and metastatic potential of a small choroidal melanoma.

DESIGN

Retrospective review of 53 patients with small choroidal melanoma treated in a tertiary oncology clinic. Patients were derived from 3 cohorts, with pathologic confirmation, with growth confirmation, and those treated only on clinical basis. Based upon prognostic biopsy outcomes, each case was classified into low or high metastatic potential groups. Distribution of clinical characteristics such as age, laterality, symptoms, tumor dimensions, tumor distance from optic nerve and fovea, presence of surface orange pigment, drusen, retinal pigment epithelial atrophy, and subretinal fluid was analyzed between metastatic groups.

MAIN OUTCOME MEASURES

Distribution of clinical characteristics between low or high metastatic potential groups was analyzed.

RESULTS

A total of 53 patients [mean age, 61 years (range, 27-81 years); 32 (60%) men and 21 (40%) women] were classified into pathology confirmed group (n = 13), growth confirmed group (n = 26), and with clinical group (n = 14). Prognostic biopsy in the growth, pathology, and clinical groups revealed low metastatic potential in 23, 10, and 11 patients, respectively, and high metastatic potential in 3 patients in each group. Distribution of clinical characteristics between low or high metastatic potential groups was not statistically significantly different.

CONCLUSION

Clinical characteristics do not identify metastatic potential of a small choroidal melanoma.

Genetic Landscape and Emerging Therapies in Uveal Melanoma

Despite successful treatment of primary uveal melanoma, up to 50% of patients will develop systemic metastasis. Metastatic disease portends a poor outcome, and no adjuvant or metastatic therapy has been FDA approved. The genetic landscape of uveal melanoma is unique, providing prognostic and potentially therapeutic insight. In this review, we discuss our current understanding of the molecular and cytogenetic mutations in uveal melanoma, and the importance of obtaining such information. Most of our knowledge is based on primary uveal melanoma and a better understanding of the mutational landscape in metastatic uveal melanoma is needed. Clinical trials targeting certain mutations such as GNAQ/GNA11, BAP1, and SF3B1 are ongoing and promising. We also discuss the role of liquid biopsies in uveal melanoma in this review.

Instrument Gauge and Type in Uveal Melanoma Fine Needle Biopsy: Implications for Diagnostic Yield and Molecular Prognostication

PURPOSE

To systematically evaluate and compare the effects of using small-gauge needles and vitrectors on the ability to obtain adequate diagnostic and prognostic uveal melanoma biopsy specimens.

DESIGN

Comparative evaluation of biopsy instruments.

METHODS

Survival of uveal melanoma cells was evaluated in vitro following needle aspiration. Five therapeutically enucleated eyes were sampled in triplicate for ex vivo diagnostic biopsy experiments with 25 gauge (25 G) needle, 27 gauge (27 G) needle, and 27 G vitrector. During surgery in 8 patients, paired diagnostic transscleral fine needle aspiration biopsies were performed using both 25 G and 27 G needles. A review of cytologic specimens was performed by a panel of 3 expert cytopathologists. A retrospective chart review was performed to evaluate 100 consecutive tumors undergoing prognostic biopsy for gene expression profiling to assess the relationship between needle gauge and prognostic adequacy.

RESULTS

No significant cell shearing of uveal melanoma cells occurred in vitro with 25 G, 27 G, or 30 G needles. For ex vivo biopsy samples, diagnostic yield was 100% using 25 G needle (5/5) or 27 G vitrector (5/5) but 60% using a 27 G needle (3/5). For in vivo samples, no difference in diagnostic yield was found between 25 G (75%, 6/8) or 27 G (75%, 6/8) needle sizes. Of 100 molecular prognostic biopsy samples evaluated, 65 were obtained using 27 G needles; for these biopsies, the prognostic yield was 65/65 (100%).

CONCLUSIONS

For diagnostic biopsy of uveal melanoma, a larger-gauge needle or a 27 G vitrector may have better overall cellularity and diagnostic yield when compared to a 27 G needle. However, for much more common molecular prognostic testing, a 27 G needle provided adequate sample in 100% (65/65) of cases, and a larger needle provided no additional benefit.