Update on posterior uveal melanoma: treatment of the eye and emerging strategies in the prognosis and treatment of metastatic disease:

Programmed Cell Death-Related Gene Signature Associated with Prognosis and Immune Infiltration and the Roles of HMOX1 in the Proliferation and Apoptosis were Investigated in Uveal Melanoma

BACKGROUND

Uveal melanoma (UVM) is the most common primary ocular malignancy, with a wide range of symptoms and outcomes. The programmed cell death (PCD) plays an important role in tumor development, diagnosis, and prognosis. There is still no research on the relationship between PCD-related genes and UVM. A novel PCD-associated prognostic model is urgently needed to improve treatment strategies.

OBJECTIVE

We aim to screen PCD-related prognostic signature and investigate its proliferation ability and apoptosis in UVM cells.

METHODS

The clinical information and RNA-seq data of the UVM patients were collected from the TCGA cohort. All the patients were classified using consensus clustering by the selected PCD-related genes. After univariate Cox regression and PPI network analysis, the prognostic PCD-related genes were then submitted to the LASSO regression analysis to build a prognostic model. The level of immune infiltration of 8-PCD signature in high- and low-risk patients was analyzed using xCell. The prediction on chemotherapy and immunotherapy response in UVM patients was assessed by GDSC and TIDE algorithm. CCK-8, western blot and Annexin V-FITC/PI staining were used to explore the roles of HMOX1 in UVM cells.

RESULTS

A total of 8-PCD signature was constructed and the risk score of the PCD signature was negatively correlated with the overall survival, indicating strong predictive ability and independent prognostic value. The risk score was positively correlated with CD8 Tcm, CD8 Tem and Th2 cells. Immune cells in high-risk group had poorer overall survival. The drug sensitivity demonstrated that cisplatin might impact the progression of UVM and better immunotherapy responsiveness in the high-risk group. Finally, Overespression HMOX1 (OE-HMOX1) decreased the cell viability and induced apoptosis in UVM cells. Recuse experiment results showed that ferrostatin-1 (fer-1) protected MP65 cells from apoptosis and necrosis caused by OE-HMOX1.

CONCLUSION

The PCD signature may have a significant role in the tumor microenvironment, clinicopathological characteristics, prognosis and drug sensitivity. More importantly, HMOX1 depletion greatly induced tumor cell growth and inhibited cell apoptosis and fer-1 protected UVM cells from apoptosis and necrosis induced by OE-HMOX1. This work provides a foundation for effective therapeutic strategy in tumour treatment.

Unsuspected and misdiagnosed posterior uveal melanoma following enucleation and evisceration in Ottawa-Gatineau

OBJECTIVE

There is a gap in the recent literature on the topic of clinically misdiagnosed and unsuspected posterior uveal melanomas (PUM) with a calculation of the frequency of these events for a specific geographical area. As the only ophthalmic pathology laboratory in our region, we determined the rate of these outcomes over a 16-year period.

METHODS

We retrospectively reviewed 2558 consecutive ophthalmic pathologic specimens in the Ottawa-Gatineau region, of which 334 were eviscerations and 227 were enucleations. We calculated the frequency of clinically misdiagnosed PUM and of clinically unsuspected PUM. We also determined the rate of uveal melanoma undergoing enucleation.

RESULTS

From 100 diagnoses of PUM, 2 (2.0%) cases were clinically unsuspected and 2 (2.0%) cases were clinically misdiagnosed. The rate of uveal melanoma undergoing enucleation was 5.6 cases per 1 000 000 of population per annum. From 2009 to 2012, the incidence of this event was 3.8 cases per 1 000 000 per annum, which was lower than the previous three 4-year increments.

CONCLUSIONS

We present the first and only single-centred, population-based data on the rates of unsuspected PUM and of clinical misdiagnosis of PUM in the era of modern diagnostic imaging. Our rate of clinical misdiagnosis is within the range of recent reports of this event. Unsuspected PUM occurred at a rate substantially lower than previously published. The incidence of uveal melanoma undergoing enucleation has decreased despite an increase in population, which reflects a shift in management from enucleation to radiation therapy.

Serum adiponectin, insulin resistance, and uveal melanoma: clinicopathological correlations

To investigate the status of insulin resistance, metabolic syndrome, dyslipidemia, and serum adiponectin levels in patients with uveal melanoma and choroidal nevus were investigated. Our study included 86 patients with uveal melanoma, 38 patients with choroidal nevus, and 86 controls. Uveal melanomas were classified as small, medium, and large on the basis of Collaborative Ocular Melanoma Study (COMS) criteria. Patients with uveal melanoma had significantly higher homeostatic model assessment scores compared with patients with choroidal nevus (P<0.001). Patients with uveal melanoma and choroidal nevus had significantly lower levels of serum adiponectin compared with controls (P<0.001). Patients with uveal melanoma who developed systemic metastases had significantly lower levels of serum adiponectin levels compared with patients with nonmetastases during follow-up (P=0.018). When the largest tumors (COMS III) were compared, ciliary body melanomas were associated with significantly lower levels of serum adiponectin than choroidal melanomas. In patients who were treated with enucleation, epitheloid predominant and mixed cell-type tumors were associated with lower levels of serum adiponectin compared with tumors with spindle cell type, but this did not reach statistical significance. By providing an antiapoptotic and proangiogenic environment, low serum adiponectin levels and insulin resistance may play a role in promoting the growth of uveal melanocytic tumors and may contribute toward a more aggressive clinical course, adversely affecting the prognosis.

Uveal melanoma hepatic metastases mutation spectrum analysis using targeted next-generation sequencing of 400 cancer genes

AIMS

Uveal melanoma (UM) is the most common malignant tumour of the eye. Diagnosis often occurs late in the course of disease, and prognosis is generally poor. Recently, recurrent somatic mutations were described, unravelling additional specific altered pathways in UM. Targeted next-generation sequencing (NGS) can now be applied to an accurate and fast identification of somatic mutations in cancer. The aim of the present study was to characterise the mutation pattern of five UM hepatic metastases with well-defined clinical and pathological features.

METHODS

We analysed the UM mutation spectrum using targeted NGS on 409 cancer genes.

RESULTS

Four previous reported genes were found to be recurrently mutated. All tumours presented mutually exclusive GNA11 or GNAQ missense mutations. BAP1 loss-of-function mutations were found in three UMs. SF3B1 missense mutations were found in the two UMs with no BAP1 mutations. We then searched for additional mutation targets. We identified the Arg505Cys mutation in the tumour suppressor FBXW7. The same mutation was previously described in different cancer types, and FBXW7 was recently reported to be mutated in UM exomes.

CONCLUSIONS

Further studies are required to confirm FBXW7 implication in UM tumorigenesis. Elucidating the molecular mechanisms underlying UM tumorigenesis holds the promise for novel and effective targeted UM therapies.

Genetic and clinico-pathologic analysis of metastatic uveal melanoma

Uveal melanoma is the most common malignant tumor of the adult eye. Fifty percent of tumors will eventually metastasize, and there are no effective treatments for them. Recent studies of uveal melanoma have identified activating mutations in GNAQ and GNA11, loss-of-function mutations in the tumor suppressor gene BAP1, and recurrent mutations in codon 625 of SF3B1. Previous studies have reported the existence of a higher frequency of GNA11 than GNAQ mutations, frequent BAP1 loss, and rare SF3B1 mutations in metastatic uveal melanoma. We analyzed a cohort of 30 uveal melanoma metastases for the occurrence of GNAQ, GNA11, and SF3B1 mutations, as well as BAP1 loss, and correlated these parameters with clinical and histopathologic features. Most (92%) tumors were composed of cells with an epithelioid or mixed (<100% spindle cells) morphology. Tumor samples composed exclusively of spindle cells were rare (n=2, 8%). Most tumors showed a moderate to marked degree of nuclear pleomorphism (n=24, 96%), and contained hyperchromatic, vesicular nuclei with variably conspicuous nucleoli. GNA11 mutations were considerably more frequent than GNAQ mutations (GNA11, GNAQ, and wild-type in 18 (60%), 6 (20%), and 6 (20%) cases, respectively). SF3B1 mutation was found in 1 of 26 tumors (4%), whereas loss of BAP1 expression was present in 13 of 16 tumors (81%). Patients with GNA11-mutant tumors had poorer disease-specific survival (60.0 vs 121.4 months, P=0.03) and overall survival (50.6 vs 121.4 months, P=0.03) than those with tumors lacking GNA11 mutations. The survival data, combined with the predominance of GNA11 mutations in metastases, raises the possibility that GNA11-mutant tumors may be associated with a higher risk of metastasis and poorer prognosis than GNAQ-mutant tumors. Further studies of uveal melanoma are required to investigate the functional and prognostic relevance of oncogenic mutations in GNA11 and GNAQ.

Transretinal uveal melanoma biopsy with 25-gauge vitrectomy system

PURPOSE

To evaluate the efficacy and the safety of uveal melanoma transretinal biopsy using 25-gauge vitrectomy system.

METHODS

At the patient's request of a tissue diagnosis, nine posterior uveal melanomas treated by proton-beam therapy were biopsied during the insertion of tantalium markers.

RESULTS

The diagnosis was uveal melanoma, confirmed in all cases using cytological (7 of 9) and histological analysis (2 of 9). Immunocytochemistry was performed on all samples (9 of 9). In eight of nine patients, minor postoperative vitreous haemorrhages were seen, which resolved in 1 day. No other ocular complications were noticed.

CONCLUSION

Uveal melanoma biopsy using 25-gauge vitrectomy system is a valuable procedure to confirm the diagnosis, with adequate sample and low ocular morbidity.

Use of Fluorescence In Situ Hybridization to Distinguish Metastatic Uveal From Cutaneous Melanoma

Metastatic lesions of malignant melanoma can on occasion be difficult to classify with regard to the primary site of origin. Given the lack of specificity of light microscopic features, ancillary studies are needed. In this study, the authors explored the possibility of distinguishing metastatic tumors derived from uveal primaries from those known to have originated from a cutaneous melanoma by fluorescence in situ hybridization (FISH) using probes for chromosome 3, 8q24, and 1p36. A total of 32 metastatic tumors were analyzed by FISH. Monosomy 3 was detected in 9 out of 16 (56.3%) cases of metastatic uveal melanoma but was not found in any of the 16 metastatic cutaneous melanomas ( P < .001). With regard to 1p36, amplifications were found in 8 out of 16 (50%) cases of metastatic cutaneous melanoma but not in any case of uveal melanoma ( P < .05). 1p36 was deleted in 3 cases of uveal and 1 case of cutaneous melanoma. Amplifications of 8q were found in 15 out of 16 (94%) cases of uveal melanoma metastases and in 12 out of 16 (75%) cases of cutaneous metastases. The findings suggest that FISH for monosomy 3 is a useful adjunct tool in the differential diagnosis of metastatic uveal versus cutaneous melanoma.

[Genomic techniques used in uveal melanoma: a literature review]

Genome study and expression profiling of the tumor seem to be the most significant biologic prognostic factor in uveal melanoma. Many cytogenetic and molecular tests are reported; our aim was to assess their ability to detect high metastatic risk patients through a literature review. Standard karyotyping, fluorescence in situ hybridization and microsatellite analysis are not adequate. DNA-based genome techniques must analyse the entire genome (comparative genomic hybridization [CGH]) and, optimally, detect chromosome 3 isodisomy ("single-nucleotid polymorphism" SNP-array). Multiplex ligation-dependent probe amplification (MLPA) is less expensive than array-CGH, but its interpretation may be delicate. Gene expression profiling is the most accurate molecular test for predicting metastatic death in patient with uveal melanoma even if it remains a costly technique. These prognostic tests could be useful to identify high-risk patients in future adjuvant therapy protocols.

Surveillance testing for metastasis from primary uveal melanoma and effect on patient survival

PURPOSE

To evaluate the quality of evidence about effectiveness of regular periodic surveillance testing for metastasis in patients with primary uveal melanoma (PUM) following treatment of the primary tumor in prolonging survival.

DESIGN

Literature review and personal perspective of the authors.

METHODS

Identification and analysis of peer-reviewed articles on human PUM published between 1980 and 2009 that reported on "screening," "surveillance," or "systemic follow-up evaluation" for metastasis in patients with PUM following treatment of primary tumor.

RESULTS

Of 4222 identified articles, only 31 were considered satisfactory for inclusion in this study. Satisfactory articles reported levels of specific biomarkers when metastasis was first confirmed (14), percentage of patients with abnormal results on surveillance testing (13), values of diagnostic markers (eg, sensitivity, specificity) associated with evaluated components of a surveillance regimen (7), survival time after first detection of metastasis from primary uveal melanoma (7), total survival time after initial diagnosis or initial treatment of primary uveal melanoma (3), percentage of patients whose metastatic tumors were detected by presymptomatic testing (5), surveillance regimens employed by different groups (1), and relationship with generally accepted clinical and histopathologic prognostic factors for primary uveal melanoma metastasis (1). However, none of these articles reported survival times of comparable subgroups of patients in which regular periodic surveillance for metastasis vs no surveillance was performed.

CONCLUSION

Available evidence from the peer-reviewed literature does not provide any compelling evidence of survival benefit for any regimen or frequency of surveillance for metastasis relative to no such testing. In view of this, advisability of periodic surveillance for metastasis in routine clinical practice must be questioned.

Uveal melanoma

Uveal melanoma is the most common primary intraocular malignancy and the leading primary intraocular disease which can be fatal in adults. In this paper epidemiologic, pathogenetic, and clinical aspects of uveal melanoma are discussed. Despite the advance in local ocular treatments, there has been no change in patient survival for three decades. Development of metastases affects prognosis significantly. Current survival rates, factors predictive of metastatic potential and metastatic screening algorithms are discussed. Proposed and emerging treatments for uveal melanoma metastases are also overviewed. Current advances in genetics and cytogenetics have provided a significant insight in tumours with high metastatic potential and the molecular mechanisms that underlie their development. Biopsy of those lesions may prove to be important for prognostication and to allow further research into genetic mutations and potential new therapeutic targets in the future.

Dormancy of metastatic melanoma

Metastatic dormancy of melanoma has not received sufficient attention, most likely because once detectable, metastasis is almost invariably fatal and, understandably, the focus has been on finding ways to prolong life of patients with overt recurrences. Nevertheless, analysis of the published clinical and experimental data on melanoma indicates that some aspect of melanoma biology imitate traits recently associated with dormancy in other solid cancers. Among them the ability of some melanomas to disseminate early during primary tumor progression and once disseminated, to remain undetected (dormant) for years. Comparison of cutaneous and uveal melanoma indicates that, in spite of being of the same origin, they differ profoundly in their clinical progression. Importantly for this discussion, between 40 and 50% of uveal melanoma remain undetected for longer than a decade, while less than 5% of cutaneous melanoma show this behavior. Both types of melanoma have activating oncogene mutations that provide autonomous pro-proliferative signals, yet the consensus is that those are not sufficient for tumor progression. If that is the case, it is possible to envision that signals from outside the tumor cell, (microenvironment) shape the fate of an individual disseminated cell, regardless of an oncogene mutation, to progress or to pause in a state of dormancy. To stimulate further debate and inquiry we describe here a few examples of potential signals that might modify the fate of disseminated cell and provide brief description of the current knowledge on dormancy in other cancers. Our hope is to convince the reader that disseminated melanoma cells do enter periods of prolonged dormancy and that finding ways to induce it, or to prolong it, might mean an extension of symptoms-free life for melanoma patients. Ultimately, understanding the biology of dormancy and the mechanisms of dormant cell survival, might allow for their specific targeting and elimination.