Primary Uveal Melanoma Research Articles

Abstract 359: Insulin-like growth factor 1 receptor (IGF-1R) as a target for treatment of metastatic uveal melanoma

Abstract Uveal melanoma is the most common primary intraocular malignant tumor in adults; 30% to 50% of patients ultimately succumb to metastatic disease, predominantly to hepatic metastasis. Despite new diagnostic and therapeutic tools, the survival rate for patients with metastatic uveal melanoma remains poor. The reason for the hepato-tropism of metastatic uveal melanoma is largely unknown. It has been reported that the type 1 insulin-like growth factor receptor (IGF-1R) is expressed in more than 70% of primary uveal melanoma tissue specimens; expression of IGF-1R is correlated to poor prognosis. IGF-1 which binds to IGF-1R is produced mainly in the liver and this may account for the hepato-tropism of uveal melanoma. In this study, we investigated the effect of IGF-1 on the in vitro growth of metastatic uveal melanoma cells. The expression of IGF-1R on a metastatic uveal melanoma cell line (UM001), established from a hepatic metastasis, was demonstrated by flow cytometry and western blot analyses. The effect of IGF-1 on tumor-cell growth was then tested by adding IGF-1 (R&D Systems, Minneapolis, MN) to the culture wells of UM001 cells with serum-free medium (SFM) containing RPMI 1640 supplemented with 50 μg/ml transferrin and 0.1% bovine serum albumin. MTT and BrdU assays were used to measure proliferative activity. Furthermore, anti-IGF-1R antibody (MAB391; R&D Systems) was added to a serum-containing culture medium to investigate the role of IGF-1 on the growth of metastatic uveal melanoma cells. IGF-1R negative (R-) and positive (R600) cell lines were used as controls in our experiments. The R- cell line was derived from a 3T3-like fibroblasts isolated from mouse embryos with a targeted disruption of the IGF-IR gene (IGF-1R negative). The R600 cell line is a stable cell line which was derived from the R- cell line and expresses 30,000 molecules of human IGF-IR/cell. Flow cytometric analysis showed that UM001 cells express IGF-1R on their surface (>90%). In western blotting analysis, UM001 cells have approximately 11,700 molecules of human IGF-IR/cell. In proliferation assays, UM001 cells in SFM were exposed to IGF-I in concentration ranging from 0 to 300 ng/ml for 72 hours. The UM001 cells proliferated in response to exogenous IGF-1 and increased BrdU uptake by 49.1% at IGF-1 level of 300 ng/ml compared to 0 ng/ml (p=0.039). In a blocking assay, UM001 cells were cultured for 24 hours in RPMI 1640 medium supplemented with 10% fetal bovine serum and antibody against either IGF-1R (30 μg/ml) or mouse IgG1 as an isotope control. We found that 30 μg/ml of anti-IGF-1R antibody blocks the proliferative activity of UM001 cells by 70%. These results suggest that IGF-1 is an important growth factor for metastatic uveal melanoma cells. Further investigation on the efficacy of IGF-1R blockade on the growth of metastatic uveal melanoma may open a new treatment approach for this disease. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 359.

Hepatische Filiae bei CUP („cancer of unknown primary“) und schmerzhafter Amaurose

A 63-year-old woman presented with a 9-month history of painful amaurosis of the left eye caused by hemophthalmos. She was already undergoing chemotherapy for histopathologically proven liver metastases caused by an assumed melanoma. The location of the primary tumor was unknown. Whole-body FDG-PET/CT staging identified a lesion with characteristically malignant uptake in the region of the left eye as the primary tumor. After enucleation, a primary uveal melanoma was verified that expressed the serological marker melanoma inhibitory activity (MIA). FDG-PET/CT was able to successfully align hepatic metastases due to CUP with local ophthalmologic diagnostic findings and led to a correct diagnosis.

Lysyl oxidase expression and inhibition in uveal melanoma

Lysyl oxidase is a marker of poor prognosis in several malignancies and is hypothesized to promote a migratory phenotype in hypoxic breast carcinomas. This study aims to characterize the expression of the lysyl oxidase and lysyl oxidase-like proteins in human uveal melanoma cell lines and archival choroidal melanomas using immunohistochemistry. The transcriptional control of lysyl oxidase will also be investigated under simulated hypoxic conditions using cobalt chloride. Lastly, changes in cellular proliferation and invasion will be assessed after the treatment of cell lines with beta-aminopropionitrile, a lysyl oxidase catalytic inhibitor. Retrospective analysis of lysyl oxidase expression in primary human uveal melanoma showed 82% (27 of 33) of tumors being stained positive. High lysyl oxidase expression correlated with the aggressive epithelioid cell type and was associated with shorter metastasis-free survival. Simulated hypoxia resulted in a significant increase in lysyl oxidase mRNA expression. Inhibiting lysyl oxidase's catalytic activity significantly reduced cellular invasion but had no effect on cell proliferation. Our study is the first to show lysyl oxidase expression in primary choroidal melanomas. This protein may represent a potential therapeutic target that warrants further study in this malignancy.

Locoregional Management of Hepatic Metastasis From Primary Uveal Melanoma

Uveal melanoma is the most common primary ocular malignancy in adults and has a significant predilection for metastasis to the liver. Despite successful treatment of the primary uveal melanoma, up to 50% of patients will subsequently develop a systemic metastasis, with the liver involved in up to 90% of these individuals. Metastatic uveal melanoma has proven to be resistant to currently available systemic chemotherapies. Recognition of the poor prognosis associated with liver metastasis has led to the evaluation of various locoregional treatment modalities primarily designed to control tumor progression in the liver, including surgical resection, hepatic arterial chemotherapy, transarterial chemoembolization (TACE), immunoembolization, radiosphere, drug-eluting beads, isolated hepatic perfusion (IHP), and percutaneous hepatic perfusion. This article reviews the efficacies, and morbidities of currently available locoregional therapies.

METOncogene Inhibition as a Potential Target of Therapy for Uveal Melanomas

PURPOSE. The purposes of this study were to investigate the frequency of MET activation in uveal melanomas (UMs), to study the potential molecular mechanism for its activation, and to assess the utility of MET inhibition as a potential therapy for UM. METHODS. The frequency of MET activation in UMs was studied by using immunohistochemistry and Western blot analysis in 46 primary UMs and six UM cell lines. Sequencing was used for detection of activating mutations in the MET gene, and the effect of selective MET inhibition was assessed by cell proliferation and migration assays. RESULTS. The results showed that the majority (82.5%) of the 46 UMs expressed activated MET protein. Three of the UM cell lines, C918, 92.1, and MEL202, showed strong MET and pMET expression, whereas the other three showed weaker expression. Sequence analysis identified no activating mutations in MET in any of the 22 tumors or in the six UM cell lines. Selective MET blocking showed inhibition of tumor cell proliferation at an IC(50) ranging from 2.5 to 5.2 microM. A significant inhibition of UM cell migration was also observed starting at 1.25 microM. CONCLUSIONS. The results indicate that MET is activated in a significant number of UMs and also that MET activation in UMs is most likely through indirect gene activation rather than copy number alteration or mutation involving the MET gene. MET inhibition could be a target of therapy for UM.

Bevacizumab suppression of establishment of micrometastases in experimental ocular melanoma.

This study was undertaken to determine whether anti-vascular endothelial growth factor (VEGF) therapy inhibits growth of primary uveal melanoma and spread of its hepatic micrometastases. The human uveal melanoma cell lines Mel290 and Mel 270, HUVECs, mouse B16LS9 melanoma cells, and mouse vascular endothelial cells were separately cultured or co-cultured and incubated with bevacizumab or IgG1. The level of VEGF protein in the culture medium was measured by ELISA. In vitro angiogenesis and invasion assays were performed under bevacizumab or IgG1 treatment. Mel290 or B16LS9 cells were inoculated into NU/NU or C57Bl/6 mouse eyes which were enucleated after 7 days. The sizes of the intraocular tumors were determined. Time and dosage experiments were performed by using 50 or 250 microg bevacizumab starting at day 1 or 4 after inoculation. Hepatic micrometastases were enumerated. Proliferation, apoptosis, and angiogenesis markers were detected in the ocular tumor by immunofluorescence staining. Bevacizumab significantly reduced the level of VEGF in the culture media from human uveal melanoma cells, mouse melanoma cells, and co-cultured cells. It also inhibited cell tube formation and decreased in vitro invasion of tumor cells. In the mouse model, bevacizumab suppressed primary ocular melanoma growth and the formation of hepatic micrometastases in a dose-dependent manner. Furthermore, immunohistochemical staining showed decreased Ki67 and unchanged caspase 3 expression after treatment with bevacizumab. Treatment with bevacizumab suppressed in vitro growth and in vivo hepatic micrometastasis of ocular melanoma cells. Bevacizumab is a potential therapeutic agent for the treatment of uveal melanoma micrometastases.

Novel Cell Lines Derived by Long-Term Culture of Primary Uveal Melanomas

Novel Cell Lines Derived by Long-Term Culture of Primary Uveal Melanomas

CXCR4-CXCL12 and VEGF correlate to uveal melanoma progression

Despite improvements in early diagnosis of uveal melanoma, prognosis is still poor due to metastases development. Neoangiogenesis and migration are requisites to metastasis promotion. Cross-talking between CXCR4-CXCL12 axis and the VEGF pathway was shown to favours tumour progression. CXCR4-CXCL12-VEGF expression was evaluated by immunohistochemistry in 53 selected cases of primary uveal melanoma and in liver melanoma metastases. CXCR4 protein was detected in 41.4 per cent cases, CXCL12 in 43.4 per cent cases and VEGF expression in 39.6 per cent cases. A significant correlation was found between CXCR4 and VEGF expression (p=0.011), CXCL12 and both tumour dimension and (p=0.006) and epithelioid-mixed cytotype (p=0.012). The two cases of uveal melanoma liver metastases in our series showed CXCR4 expression, weak immunoreactivity for CXCL12 and absent VEGF immunostaining. These data indicate that CXCR4-CXCL12 axis and its cross-talking with VEGF plays a role in uveal melanoma metastases and may be new prognostic markers in UMM. Moreover, these results suggest that targeted inhibition of CXCR4 could be introduced to control metastasis development in UMM.

Characterizing the Involvement of the Nuclear Factor-kappa B (NFκB) Transcription Factor in Uveal Melanoma

Purpose. To examine the involvement of nuclear factor-kappa B (NFkappaB) pathways in uveal melanoma (UM) and to assess their potential as a therapeutic target for metastatic UM. Methods. Samples from primary (n = 7) and metastatic (n = 7) UM were evaluated for NFkappaB transcription factor family expression by quantitative PCR (QPCR), immunofluorescent staining, and Western blot analysis. The effect of two NFkappaB inhibitors, DHMEQ and BMS-345541, on two cell lines derived from UM liver metastases was assessed. Cell proliferation was examined by MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay, methylene blue assay, and immunostaining for Ki-67. Apoptosis was assessed by immunostaining for activated caspase 3. Results. NFkappaB1, NFkappaB2, RelA, RelB, and NIK were expressed in primary UM and in its liver metastases. NFkappaB2, RelB, and NIK showed significantly higher mRNA levels in metastases from UM compared with primary tumors (3.4-fold, P = 0.03; 3.6-fold, P = 0.05; 3.5-fold, P = 0.03; respectively). NFkappaB2 protein activation was 3.9-fold higher in metastases (P = 0.03). NFkappaB inhibition reduced metastatic cell proliferation by 9.2-fold and 1.9-fold according to Ki67 staining (P = 0.04) and methylene blue assay (P = 6 x 10(-7)), respectively. Both NFkappaB inhibitors achieved dose-dependent reductions of UM cell proliferation in both cell lines (P < 0.001). NFkappaB inhibition resulted in a 6.3-fold increase of apoptosis (P = 7 x 10(-7)). Conclusions. These data indicate that the NFkappaB1 and NFkappaB2 pathways are active in both primary and metastatic UM and that these pathways regulate metastatic cell proliferation and apoptosis. The role of NFkappaB as a therapeutic target for UM should be further evaluated.

Possible Implications of MCAM Expression in Metastasis and Non-Metastatic of Primary Uveal Melanoma Patients

Purpose: To evaluate the expression of melanoma cell adhesion molecule (MCAM) as prognostic factor in uveal melanoma patients.Methods: Paraffin sections from 35 primary uveal melanomas were analyzed immunhistochemically for the expression of MCAM. Further known prognostic factors such as cell type, ciliary body invasion, tumor stage, and local extension were evaluated. In 16 cases, patients had developed metastatic disease. The patients without metastasis (n = 19) had a mean follow-up of 10.6 (9–13) years.Results: All tumors were positive for MCAM (mean: 57.05%). In the group without metastasis, an average MCAM expression of 35.37% (SD 19.66%) compared to 82.78% (SD 11.73%) in the metastasis group was found. The Cox regression analysis showed a significant association of an enhanced MCAM expression and death due to metastasis (HR: 365.48, 95% CI: 18.51, 7217.85).Conclusion: MCAM expression of primary uveal melanomas can serve as a possible prognostic parameter for metastasis. If further experiments approve the cellular adhesion molecules to account for early micrometastasis of tumor cells, a possible target might be available for future treatment.

Chromosomal 3 and 8 Status Within Hepatic Metastasis of Uveal Melanoma

Abstract Context.—Several studies have evaluated clinical, histopathologic, cytogenetic, and molecular prognostic variables in uveal melanoma. However, it is not known whether the primary tumor cells maintain these aggressive attributes at the metastatic sites. Objective.—To determine the status of chromosomes 3 and 8q and c-myc amplification using fluorescence in situ hybridization on hepatic metastatic lesions of primary uveal melanoma. Design.—Ten patients with uveal melanoma with needle core biopsy–confirmed hepatic metastasis. Representative paraffin blocks were selected based on review of hematoxylin-eosin–stained sections. Fluorescence in situ hybridization was performed for detection of monosomy 3 and amplification at the 8q24 MYC locus using standard methods. The tricolor chromosome enumeration probe 8 (CEP8)/ IGH/MYC and the Urovysion probe consisting of CEP3, CEP7, CEP17, and 9P21 probes were used. A total of 200 interphase cells were scored. Results.—Hepatic metastasis was confirmed in each ca...

Circulating melanoma cells in peripheral blood of patients with uveal melanoma before and after different therapies and association with prognostic parameters: a pilot study

To evaluate whether tumour therapy for malignant uveal melanoma leads to a shedding of melanoma cells into the systemic circulation. Ninety-four peripheral blood samples from 81 patients with malignant uveal melanoma were collected before and after different tumour therapies and the number of circulating melanoma cells (CMCs) was investigated (seven patients with enucleation, 49 patients with stereotactic radiotherapy, 19 patients with endoresection of the tumour, 15 patients with ruthenium-brachytherapy and four patients with transpupillary thermotherapy). A cellular approach was used to detect CMCs through an immunocytological assay with tumour cell enrichment by immunomagnetic cell sorting. The number of CMCs was analysed further according to specific patient characteristics, tumour parameters and the development of metastasis. There was no significant difference between the number of CMCs before and after the different therapies (p = 0.78). There was also no significant association between established prognostic parameters of primary uveal melanoma and the detection of CMCs (all p >0.05). The number of CMCs was not related to the development of metastasis in a short median follow-up time of 16 months (p > 0.05). No changes in CMC values were observed before and after different tumour therapies. In the majority of cases therapy does not lead to a shedding of detectable melanoma cells into the systemic circulation.

Heterogeneity in uveal melanoma assessed by multiplex ligation‐dependent probe amplification (MLPA)

Abstract Purpose To study intratumour heterogeneity in primary uveal melanoma (UM) by MLPA in microdissected formalin‐fixed, paraffin‐embedded (FFPE) tissues. Methods DNA was extracted from 2‐9 areas microdissected from 32 FFPE UMs. Thirty‐one loci on chromosomes 1p, 3, 6 and 8 were tested for copy number changes using the SALSA MLPA P027.B1 assay (MRC Holland). MLPA data were displayed as dosage quotients (DQs), which were classified to 5 ranges (0.35‐0.64 deleted; 0.65‐0.84 equivocal deletion; 0.85‐1.14 normal; 1.15‐1.35 equivocal amplification; &gt;1.35 amplified). The tumour was considered heterogeneous at a locus, if a) the difference in DQs of any two areas was higher than 0.2 (value determined by ROC analysis), and b) the DQs of the areas belonged to different ranges. Results Genetic abnormalities were detected in all 32 UMs. Monosomy 3, the most significant metastasis predictor, and gain of 8q genes MYC or DDEF1 were detected in at least 1 microdissected area of 22 (69%) and 28 (87%) of the tumours, respectively. The comparison of MLPA data obtained from different areas of UMs showed heterogeneity in 1‐24 loci across chromosomes 1p, 3, 6 and 8 in 26 (81%) tumours. Interestingly, trisomy 3 was observed in 3 (9%) UMs and these tumours showed the highest degree of heterogeneity (&gt;23 heterogeneous loci). Intratumour heterogeneity of 3p12.2 (ROBO1) and 6p21.2 (CDKN1A) were most common and present in more than 35% of the tumours. Conclusion Heterogeneity of chromosomal abnormalities of 1p, 3, 6 and 8 is present in many UM. Taking one random tumour sample for prognostic testing, therefore, may not be representative of the whole tumour.

Chromosomal 3 and 8 Status Within Hepatic Metastasis of Uveal Melanoma

Several studies have evaluated clinical, histopathologic, cytogenetic, and molecular prognostic variables in uveal melanoma. However, it is not known whether the primary tumor cells maintain these aggressive attributes at the metastatic sites. To determine the status of chromosomes 3 and 8q and c-myc amplification using fluorescence in situ hybridization on hepatic metastatic lesions of primary uveal melanoma. Ten patients with uveal melanoma with needle core biopsy-confirmed hepatic metastasis. Representative paraffin blocks were selected based on review of hematoxylin-eosin-stained sections. Fluorescence in situ hybridization was performed for detection of monosomy 3 and amplification at the 8q24 MYC locus using standard methods. The tricolor chromosome enumeration probe 8 (CEP8)/IGH/MYC and the Urovysion probe consisting of CEP3, CEP7, CEP17, and 9P21 probes were used. A total of 200 interphase cells were scored. Hepatic metastasis was confirmed in each case by needle core biopsy. Fluorescence in situ hybridization analysis revealed chromosome 3 monosomy in 5 of the 8 cases that could be satisfactorily evaluated. Aneusomy of chromosome 8 was observed in 2 cases. MYC amplification was observed in 5 samples. In a single case where the primary tumor was treated by enucleation, the chromosomal monosomy 3 and aneusomy of chromosome 8 were present both in the primary tumor and its hepatic metastatic lesion. The presence of cytogenetic changes within the metastatic lesions confirms that chromosome 3 monosomy and aneusomy of chromosome 8 are not just markers of metastatic potential of the primary tumor but are also present within the hepatic metastatic lesions.

Proteomics of Uveal Melanomas Suggests HSP-27 as a Possible Surrogate Marker of Chromosome 3 Loss

To compare the proteomic profiles of primary uveal melanomas, with and without loss of chromosome 3. Frozen specimens from three uveal melanomas with disomy 3 and from four tumors with monosomy 3, according to fluorescence in situ hybridization (FISH) analysis, were subjected to high-resolution, two-dimensional (2-D) gel electrophoresis. The protein expression profiles of the two uveal melanoma cytogenetic groups were compared: Proteins that differed significantly were excised and analyzed by tandem mass spectrometry. Differentially expressed proteins were further analyzed with Western blot analysis. An independent cohort of 41 formalin-fixed, paraffin-embedded (FFPE) uveal melanomas, whose chromosome 3 status had been determined by multiplex ligation-dependent probe amplification (MLPA), was examined for the appropriate antigens by immunohistochemistry. Four protein spots were 1.5-fold (Student's t-test, P < 0.05) differentially expressed in the two uveal melanoma types: two spots were overexpressed in the disomy 3 group compared with the monosomy 3 group, whereas two spots were underexpressed. Identification of the four spots yielded nine proteins. Western blot analysis confirmed the results for heat shock protein (HSP)-27, vimentin, and pyruvate dehydrogenase beta (PDHB), with a statistical significance for the first two proteins. HSP-27 was significantly downregulated, whereas vimentin was upregulated in the monosomy 3 tumors (Student's t-test, P = 0.003 and P = 0.005, respectively). Immunohistochemistry confirmed low-to-negative HSP-27 protein expression in monosomy 3 uveal melanomas (Student's t-test; P = 0.011). Low-to-negative HSP-27 protein expression in uveal melanoma correlates strongly with monosomy 3. Further validation is necessary to determine whether immunohistochemical assessment of HSP-27 expression correlates with metastatic mortality.

Episodic Src activation in uveal melanoma revealed by kinase activity profiling

Background:The RAS/RAF/MEK/ERK pathway is involved in the balance between melanocyte proliferation and differentiation. The same pathway is constitutively activated in cutaneous and uveal melanoma (UM) and related to tumour growth and survival. Whereas mutant BRAF and NRAS are responsible for the activation of the RAS/RAF/MEK/ERK pathway in most cutaneous melanoma, mutations in these genes are usually absent in UM.Methods:We set out to explore the RAS/RAF/MEK/ERK pathway and used mitogen-activated protein kinase profiling and tyrosine kinase arrays.Results:We identified Src as a kinase that is associated with ERK1/2 activation in UM. However, low Src levels and reduced ERK1/2 activation in metastatic cell lines suggest that proliferation in metastases can become independent of Src and RAS/RAF/MEK/ERK signalling. Inhibition of Src led to the growth reduction of primary UM cultures and cell lines, whereas metastatic cell line growth was only slightly reduced.Conclusion:We identified Src as an important kinase and a potential target for treatment in primary UM. Metastasis cell lines seemed largely resistant to Src inhibition and indicate that in metastases treatment, a different approach may be required.

Uveal melanoma cell-based vaccines express MHC II molecules that traffic via the endocytic and secretory pathways and activate CD8+ cytotoxic, tumor-specific T cells

We are exploring cell-based vaccines as a treatment for the 50% of patients with large primary uveal melanomas who develop lethal metastatic disease. MHC II uveal melanoma vaccines are MHC class I(+) uveal melanoma cells transduced with CD80 genes and MHC II genes syngeneic to the recipient. Previous studies demonstrated that the vaccines activate tumor-specific CD4(+) T cells from patients with metastatic uveal melanoma. We have hypothesized that vaccine potency is due to the absence of the MHC II-associated invariant chain (Ii). In the absence of Ii, newly synthesized MHC II molecules traffic intracellularly via a non-traditional pathway where they encounter and bind novel tumor peptides. Using confocal microscopy, we now confirm this hypothesis and demonstrate that MHC II molecules are present in both the endosomal and secretory pathways in vaccine cells. We also demonstrate that uveal melanoma MHC II vaccines activate uveal melanoma-specific, cytolytic CD8(+) T cells that do not lyse normal fibroblasts or other tumor cells. Surprisingly, the CD8(+) T cells are cytolytic for HLA-A syngeneic and MHC I-mismatched uveal melanomas. Collectively, these studies demonstrate that MHC II uveal melanoma vaccines are potent activators of tumor-specific CD4(+) and CD8(+) T cells and suggest that the non-conventional intracellular trafficking pattern of MHC II may contribute to their enhanced immunogenicity. Since MHC I compatibility is unnecessary for the activation of cytolytic CD8(+) T cells, the vaccines could be used in uveal melanoma patients without regard to MHC I genotype.

Presumed primary uveal melanoma with brain extension in a dog

A 13-year-old, female, mixed, cocker spaniel was examined for a unilateral exophthalmia and protruding mass in episcleral region of the right eye. Mode B ocular ultrasonography revealed a mass extended intraocular from anterior chamber to posterior pole without evidence of extraocular extension. A presumptive diagnosis of melanocytic tumour was made. A complete blood count and chemistry and thoracic radiographs did not show any abnormal changes. The recommended treatment was enucleation, and melanocytic nature of the tumour was confirmed by immunohistochemistry. Three months after surgery, the animal showed a status epilepticus refractory to treatment. Computed tomographic examination of the brain revealed changes compatible with a tumour. Cerebrospinal fluid analysis was normal. Because of the poor clinical prognosis, the owners elected to have the dog euthanased.

Activated CD11b+CD15+Granulocytes Increase in the Blood of Patients with Uveal Melanoma

To determine whether activated CD11b(+) CD15(+) granulocytes increase in the blood of patients with uveal melanoma. Peripheral blood mononuclear cells (PBMCs) were isolated by density gradient centrifugation from the blood of patients with primary choroidal/ciliochoroidal uveal melanomas (six women, four men; age range, 46-91 years) and healthy control donors (14 women, 10 men; age range, 50-81 years). The expression of CD15 and CD68 on CD11b(+) myeloid cells within PBMCs and primary uveal melanomas was evaluated by flow cytometry. CD3zeta chain expression by CD3epsilon(+) T cells in PBMCs and within primary uveal melanomas was measured as an indirect indication of T-cell function. The percentage of CD11b(+) cells in PBMCs of patients with uveal melanoma increased 1.8-fold in comparison to healthy donors and comprised three subsets: CD68 negative CD15(+) granulocytes, which increased 4.1-fold; CD68(-) CD15(-) cells, which increased threefold; and CD68(+) CD15(low) cells, which were unchanged. A significant (2.7-fold) reduction in CD3zeta chain expression on CD3epsilon(+) T cells, a marker of T-cell dysfunction, was observed in PBMCs of patients with uveal melanoma in comparison with healthy control subjects and correlated significantly with the percentage of CD11b(+) cells in PBMCs. CD3zeta chain expression on T cells within primary tumors was equivalent to CD3zeta expression in PBMCs of the same patient in four of five patients analyzed. Activated CD11b(+) CD15(+) granulocytes expand in the blood of patients with uveal melanoma and may contribute to immune evasion by ocular tumors by inhibiting T-cell function via decreasing CD3zeta chain expression.

Mortality after uveal and conjunctival melanoma: which tumour is more deadly?

We aimed to model and compare mortality rates for uveal melanoma (UM) and conjunctival melanoma (CM) by adjusting for differences in tumour size and local recurrence. Population-based mortality data for 240 and 85 patients with primary UM and CM and 91 and 23 patients with disseminated UM and CM, respectively, were compared with cumulative incidence analysis. Cox proportional hazards multivariate regression with time-dependent variables was used to adjust for differences in tumour diameter, thickness and recurrence rates. The 10-year cumulative incidences of metastatic death from UM and CM were 39% (95% confidence interval [CI] 33-45) and 32% (95% CI 21-44), respectively. After adjusting for tumour size, risk of death from CM was higher than from UM (hazard ratio [HR] 1.9; p = 0.039). Additional adjustment for more frequent local recurrence of CM diminished the difference (HR 1.5; p = 0.25). Survival periods after systemic metastasis of UM and CM were comparable (median 8 months). Clinical observations show longer survival after primary CM than after primary UM. This reflects the smaller average size of CM. However, a primary CM of a given size is more deadly than a UM of equivalent size because primary CM tends to recur after treatment and, possibly, because additional lymphatic dissemination occurs with CM.