Obesity paradox in uveal melanoma: high body mass index is associated with low metastatic risk

BACKGROUND

Metabolic factors and obesity may influence the development and progression of cancer. In this study, we examine their association with the risk of developing metastases of uveal melanoma.

METHODS

Data on metabolic factors, medications, serum leptin levels, tumour leptin receptor RNA expression and clinical outcomes were examined in three cohorts. HRs for metastasis and cumulative incidences of melanoma-related mortality were calculated, and the levels of tumour leptin receptor expression were compared with prognostic factors including BAP1 mutation, and tumour cell morphology.

RESULTS

Of 581 patients in the main cohort, 116 (20%) were obese and 7 (1 %) had metastatic disease at presentation. In univariate Cox regressions, tumour diameter, diabetes type II and use of insulin were associated with metastases, but patients with obesity had a lower risk. The beneficial prognostic implication of obesity was retained in multivariate regressions. In competing risk analyses, the incidence of melanoma-related mortality was significantly lower for patients with obesity. Serum leptin levels≥median were associated with a reduced risk for metastasis, independent of patient sex and cancer stage in a separate cohort (n=80). Similarly, in a third cohort (n=80), tumours with BAP1 mutation and epithelioid cells had higher leptin receptor RNA expression levels, which have a negative correlation with serum leptin levels.

CONCLUSION

Obesity and elevated serum leptin levels are associated with a lower risk for developing metastases and dying from uveal melanoma.

Prognostic implications of tenascin C in peripheral blood and primary tumours at the time of uveal melanoma diagnosis

OBJECTIVE

To examine the prognostic implication of tenascin C (TNC) in posterior uveal melanoma (UM).

DESIGN

Retrospective cohort study.

PARTICIPANTS

A total of 162 patients diagnosed with posterior UM.

METHODS

A peripheral blood sample was obtained from 82 patients at the time of UM diagnosis between 1996 and 1999. Samples were kept frozen at -80°C until the concentration of TNC was measured in 2021. Primary tumour TNC RNA sequencing data were collected from another 80 patients (The Cancer Genome Atlas cohort). Patients were separated based on median TNC values. Cumulative incidences of metastatic death (UM mortality) from competing risks data were calculated as well as Cox regression hazard ratios.

RESULTS

Patients with high and low TNC levels had tumours of similar size and American Joint Committee on Cancer stage at Bonferroni-corrected significance levels. The exception was a significantly smaller tumour diameter in patients with high serum TNC levels (p = 0.003). In competing risks analysis, patients with high serum TNC levels (≥7 ng/mL) had a higher UM mortality rate (44% vs 17% at 20 years; p = 0.008). Similarly, patients with higher primary tumour TNC RNA levels (≥1 transcripts per million) had higher UM mortality (83% vs 27% at 5 years; p = 0.003). In multivariate Cox regressions, TNC levels in peripheral blood and primary tumours were predictors of metastatic death independent of American Joint Committee on Cancer stage.

CONCLUSIONS

TNC is a prognostic biomarker in UM. At the time of primary tumour diagnosis, it is measured in higher levels in both peripheral blood and tumour tissue from patients who will eventually suffer from metastatic death.

A serum protein signature at the time of Uveal Melanoma diagnosis predicts long-term patient survival

PURPOSE

To develop a prognostic test based on a single blood sample obtained at the time of uveal melanoma diagnosis.

METHODS

83 patients diagnosed with posterior uveal melanoma between 1996 and 2000 were included. Peripheral serum samples were obtained at diagnosis and kept at -80 °C until this analysis. Protein profiling of 84 cancer-related proteins was used to screen for potential biomarkers and a prognostic test that stratifies patients into metastatic risk categories was developed (serUM-Px) in a training cohort and then tested in a validation cohort.

RESULTS

Low serum leptin levels and high osteopontin levels were found to identify patients with poor prognosis and were therefore selected for inclusion in the final test. In the validation cohort, patient sex and American Joint Committee on Cancer stages were similarly distributed between the low, intermediate, and high metastatic risk categories. With increasing metastatic risk category, patients had shorter metastasis-free- and overall survival, as well as greater cumulative incidence of uveal melanoma-related mortality in competing risk analysis (P = 0.007, 0.018 and 0.029, respectively). In multivariate Cox regression, serUM-Px was an independent predictor of metastasis with tumor size and patient sex as covariates (hazard ratio 3.2, 95% CI 1.5-6.9).

CONCLUSIONS

A prognostic test based on a single peripheral venous blood sample at the time of uveal melanoma diagnosis stratifies patients into low, intermediate, and high metastatic risk categories. Prospective validation will facilitate its clinical utility.

A prognostic classification system for uveal melanoma based on a combination of patient age and sex, the American Joint Committee on Cancer and the Cancer Genome Atlas models

PURPOSE

To revisit the independent importance of ciliary body involvement (CBI), monosomy 3 (M3), tumour size, histological and clinical factors in uveal melanoma (UM) and to devise a new prognostic classification based on a combination of the American Joint Committee on Cancer (AJCC) and the Cancer Genome Atlas (TCGA) models.

METHODS

Two cohorts with a total of 1796 patients were included. Clinicopathological factors were compared between patients with and without CBI and M3. Development of the prognostic classification was performed in a training cohort and was then tested in two independent validation cohorts.

RESULTS

Tumours with CBI were more common in women, had greater apical thickness, greater basal tumour diameter, greater rates of vasculogenic mimicry and greater rates of M3, were more often asymptomatic at diagnosis and had poorer 5- and 10-year globe conservation rates (p < 0.023). In multivariate logistic regression, patient age at diagnosis, tumour diameter and CBI were independent predictors of M3 (p < 0.001). In multivariate Cox regression, male sex, age at diagnosis, tumour diameter, M3 and CBI were independent predictors of metastasis. The proposed prognostic classification combined patient age, sex, CBI, extraocular extension, M3, 8q (optional) and tumour size, and demonstrated greater prognostic acumen than both AJCC 4 T categories and TCGA groups A to D in validation cohorts.

CONCLUSIONS

Tumour size does not confound the prognostic implication of CBI, M3, male sex and age at diagnosis in UM. These factors were included in a new prognostic classification that outperforms AJCC T category and TCGA groups.

Trends in Uveal Melanoma Presentation and Survival During Five Decades: A Nationwide Survey of 3898 Swedish Patients

Background

In contrast to most other cancers, uveal melanoma (UM) is characterized by an absence of major improvements in patient survival during the last several decades. In this study, we examine changes in incidence rates, patient age and tumor size at diagnosis, treatment practices and survival for patients diagnosed in Sweden during the period 1960-2010.

Methods

All patients diagnosed with posterior UM between January 1st, 1960, and December 31st, 2009, in Sweden, were included (n = 3898). Trends in incidence, primary treatment modality, patient age and tumor size were analyzed. Disease-specific survival was plotted in Kaplan-Meier curves and the cumulative incidence of UM-related mortality was evaluated in competing risk analysis.

Results

Crude (6.5-11.6 cases/million/year) and age-standardized incidence rates (5.6-9.6 cases/million/year) varied between individual years during the study period, but both had a stable linear trend overall (p ≥ 0.12). Gradually, plaque brachytherapy with ruthenium-106 replaced enucleation as the most common primary treatment. The mean patient age at diagnosis increased from 59.8 years in 1960 to 66.0 in 2009. Conversely, the mean tumor size became gradually smaller during the period. In linear regression, the basal diameter and tumor apical thickness decreased with a slope coefficient of -0.03 mm (p = 0.012) and -0.05 mm (p = 1.2 × 10^-5) per year after 1960, respectively. Patients diagnosed after 1990 had significantly better disease-specific survival than patients diagnosed before 1990 (p = 2.0 × 10^-17). Similarly, the cumulative incidence of UM-related mortality was highest for patients diagnosed 1960-1969 and 1970-1979, with slightly lower incidences for patients diagnosed 1980-1989 and even lower for those diagnosed after 1990 (p = 7.1 × 10^-13). The incidence of mortality from other causes than UM did not differ between periods (p = 0.16).

Conclusion

In the period from 1960-2010, crude and age-standardized incidence rates of UM have remained stable in Sweden. Several other aspects have changed: Plaque brachytherapy with ruthenium-106 has replaced enucleation as the most common primary treatment modality; patients have become older and their tumors smaller at the time of diagnosis; and their survival has improved. This might indicate a beneficial survival effect of earlier diagnosis and treatment, but the potential influence from lead-time bias should be taken into consideration.

Long-term relative survival in uveal melanoma: a systematic review and meta-analysis

Background

A large proportion of patients with uveal melanoma develop metastases and succumb to their disease. Reports on the size of this proportion vary considerably.

Methods

PubMed, Web of Science and Embase were searched for articles published after 1980. Studies with ≥100 patients reporting ≥five-year relative survival rates were included. Studies solely reporting Kaplan-Meier estimates and cumulative incidences were not considered, due to risk for competing risk bias and classification errors. A meta-analysis was performed using random-effects and weighted averages models, as well as a combined estimate based on curve fitting.

Results

Nine studies and a total of 18 495 patients are included. Overall, the risk of selective reporting bias is low. Relative survival rates vary across the population of studies (I2 48 to 97% and Qp < 0.00001 to 0.15), likely due to differences in baseline characteristics and the large number of patients included (τ2 < 0.02). The 30-year relative survival rates follow a cubic curve that is well fitted to data from the random-effects inverse-variance and weighted average models (R2 = 0.95, p = 7.19E−7). The estimated five, ten, 15, 20, 25 and 30-year relative survival rates are 79, 66, 60, 60, 62 and 67%, respectively.

Conclusions

The findings suggest that about two in five of all patients with uveal melanoma ultimately succumb to their disease. This indicates a slightly better prognosis than what is often assumed, and that patients surviving 20 years or longer may have a survival advantage to individuals of the same sex and age from the general population.

No differences in the long-term prognosis of iris and choroidal melanomas when adjusting for tumor thickness and diameter

Objective

To assess the long-term prognosis for patients with iris melanomas and compare it with the prognosis for small choroidal melanomas.

Design

Retrospective observational case series.

Methods

All patients treated for iris melanomas at a single referral institution between January 1st 1986 and January 1st 2016 were included. Patients treated for small choroidal melanomas during the same period were included for comparison. The cumulative incidence of melanoma-related mortality was calculated. Patient and tumor characteristics and size-adjusted hazard ratio (HR) for melanoma-related mortality were compared between iris and small choroidal melanomas.

Results

Forty-five iris melanomas and 268 small choroidal melanomas were included. Twenty-four iris melanomas (53%) had been treated with local resection, 12 (27%) with Ruthenium-106 brachytherapy, 7 (16%) with enucleation and 2 (4%) with proton beam irradiation. Twenty-one (68%), 7 (16%) and 2 (4%) of the iris melanomas were of the spindle, mixed and epithelioid cell types, respectively. Twenty-three patients had deceased before the end of follow-up. Median follow-up for the 22 survivors was 13.3 years (SD 9.4). Patients with iris melanomas were more often asymptomatic at presentation and had a trend towards significantly lower age (59 versus 63 years, Student’s T-tests p = 0.057). Further, iris melanomas had significantly smaller basal diameter (5.8 versus 8.0 mm, p < 0.0001) and tumor volume (79 mm³ versus 93 mm mm³, p < 0.0001) but greater thickness (3.0 versus 2.5 mm, p < 0.0001). The cumulative incidence of iris melanoma-related mortality was 5% at 5 years after diagnosis, and 8% at 10, 15 and 20 years. The incidence was not significantly different to small choroidal melanomas (Wilcoxon p = 0.46). In multivariate Cox regression with tumor diameter and thickness as covariates, patients with choroidal melanomas did not have increased HR for melanoma-related mortality (HR 2.2, 95% CI 0.5–9.6, p = 0.29). Similarly, there were no significant survival differences in matched subgroups (Wilcoxon p = 0.82).

Conclusions

There are no survival differences between iris and choroidal melanomas when adjusting for tumor size. The reason for the relatively favorable prognosis of iris melanomas compared to melanomas of the choroid and ciliary body is likely that they are diagnosed at a smaller size.

Vasculogenic mimicry correlates to presenting symptoms and mortality in uveal melanoma

PURPOSE

Fluid-conducting extracellular matrix patterns known as vasculogenic mimicry (VM) have been associated with poor prognosis in uveal melanoma and other cancers. We investigate the correlations between VM, presenting symptoms, mortality, and the area density of periodic acid-Schiff positive histological patterns (PAS density).

METHODS

Sixty-nine patients that underwent enucleation for uveal melanoma between 2000 and 2007 were included. Clinicopathological parameters presenting symptoms and outcomes were collected. Histological tumor sections were evaluated for VM and PAS density was quantified with digital image analysis.

RESULTS

Thirty-four patients (49%) presented with blurred vision. 18 (26%) with a shadow in the visual field, 7 (10%) with photopsia and/or floaters, and 2 (3%) with metamorphopsia. Nine patients (13%) had no symptoms at all. Median follow-up was 16.7 years (SD 2.6). A shadow in the visual field, but no other symptom, was positively correlated with the presence of VM (φ 0.70, p < 0.001) and greater PAS density (p < 0.001). In multivariate regression, retinal detachment (RD), presence of VM, and PAS density ≥ median were independent predictors of a shadow, but not tumor distance to the macula, tumor apical thickness, tumor diameter, or ciliary body engagement. The presence of VM was associated with significantly shorter cumulative disease-specific survival (Wilcoxon p = 0.04), but not PAS density ≥ median, presenting symptoms or RD (p > 0.28).

CONCLUSION

Tumors from uveal melanoma patients that report a visual field shadow are likely to display VM and greater PAS density, likely explaining the previously reported association between this symptom and poor prognosis.

Nuclear expression of BAP-1 in transvitreal incisional biopsies and subsequent enucleation of eyes with posterior choroidal melanoma

BACKGROUND

As a majority of patients with choroidal melanoma do not undergo enucleation, tumour tissue for prognostic testing has to be obtained with alternate methods. Transvitreal incisional biopsies enable histological examination as well as immunohistochemical staining of BRCA1-associated protein-1 (BAP-1).

METHODS

Fifty-nine patients diagnosed with choroidal melanoma in transvitreal biopsies between years 2003 and 2019 were included. Twenty-one of these patients subsequently underwent enucleation. The level of nuclear expression of BAP-1 in transvitreal biopsies and enucleations was evaluated and the concordance calculated. Metastasis-free survival and HR for metastasis were analysed.

RESULTS

The mean tumour thickness and diameter at biopsy was 3.8 mm (SD 2.1) and 9.3 mm (SD 4.8), respectively. For biopsies, 37 of 59 tumours (63%) were classified as having high nuclear BAP-1 expression, and 22 (37%) as low. For enucleations, 13 of 21 tumours (62%) were classified as having high nuclear BAP-1 expression, and 8 (38%) as low. Eighty-six per cent of biopsies had an identical BAP-1 classification as the subsequent enucleation, yielding a Cohen's kappa coefficient of 0.70. Patients with low nuclear BAP-1 expression in transvitreal biopsies had a significantly shorter metastasis-free survival (p=0.001), with a size-adjusted Cox regression HR for metastasis of 13.0 (95% CI 3.1 to 54.4, p=0.0004).

CONCLUSION

Loss of nuclear BAP-1 expression occurred in a large proportion of the small tumours included in this study. BAP-1 immunoreactivity in transvitreal incisional biopsies of choroidal melanoma is substantially concordant with immunoreactivity in enucleated specimens and identifies patients with poor metastasis-free survival.

Effect of plaque brachytherapy dose and dose rate on risk for disease-related mortality in 1238 patients with choroidal melanoma

BACKGROUND

Episcleral brachytherapy is the most common treatment for medium-sized choroidal melanomas. Although controversial, inadequate brachytherapy dose and dose rates have at least a hypothetical implication on patient survival.

METHODS

All patients who received ruthenium-106 or iodine-125 brachytherapy for choroidal melanoma at St. Erik Eye Hospital 1996 to 2016 were included (n=1238). Cox regression hazard ratios for melanoma-related mortality across deciles, quartiles and individual integers of apex radiation doses (Gy) and dose rates (Gy/hour) were calculated, adjusted for tumour size and location.

RESULTS

The average radiation dose at the tumour apex ranged from 73.0 Gy in the first decile to 108.6 Gy in the tenth. Decreasing apex dose by 1 Gy increments or by decile or quartile group was not associated with melanoma-related mortality (p>0.2) The average radiation dose rate at the tumour apex ranged from 0.5 Gy/hour in the first decile to 2.8 Gy/hour in the tenth. Similarly, decreasing apex dose rate by 1 Gy/hour increments or by decile or quartile groups was not associated with melanoma-related mortality (p>0.5).

CONCLUSION

There are no increased hazards for choroidal melanoma-related mortality after brachytherapy with decreasing doses between 108.6 and 73.0 Gy, or with decreasing dose rates between 2.8 and 0.5 Gy/hour.

Digital morphometry of tumor nuclei correlates to BAP-1 status, monosomy 3, gene expression class and survival in uveal melanoma

Cytologic features such as the shape and size of tumor cells can predict metastatic death in uveal melanoma and other cancers but suffer from poor reproducibility. In this study, we investigate the interobserver concordance of digital morphometry, and correlate the results with BRCA associated protein-1 (BAP-1) expression and BAP-1 gene mutation status, monosomy 3, gene expression classifications and patient survival in uveal melanoma. The average number of cells analyzed in each of 107 tumors, was 1957 (SD 349). Mean time consumption was less than 2.5 min per tumor. Identical morphometric classification was obtained for ≥85% of tumors in all twelve evaluated morphometric variables (κ 0.70-0.93). The mean nucleus area, nucleus perimeter, nucleus max caliper and nucleus to cell area ratio were significantly greater in tumors with low BAP-1 expression and gene expression class 2. Patients had significantly shorter survival if their tumors had low BAP-1 (Log-Rank p = 0.002), gene expression class 2 (p = 0.004), long nucleus perimeters (p = 0.031), long nucleus max calipers (p = 0.029) and high mean nucleus to cell area ratios (p = 0.041) as defined in a training cohort and then tested in a validation cohort. Long nucleus perimeters and long nucleus max calipers correlated with monosomy 3 (Pearson Chi-Square p = 0.006 and p = 0.009, respectively). Long nucleus perimeters also correlated with BAP-1 mutation (p = 0.017). We conclude that digital morphometry can be fast and highly reproducible, that for the first time, morphometry parameters can be objectively quantitated in thousands of cells at a time in sub-μm resolutions, and that variables describing the shape and size tumor nuclei correlate to BAP-1 status, monosomy 3, gene expression class as well as patient survival.

Effect of glycosylated hemoglobin on response to ranibizumab therapy in diabetic macular edema: real-world outcomes in 312 patients

OBJECTIVE

To investigate the effect of serum glycosylated hemoglobin (HbA1c) on the outcomes of ranibizumab therapy for diabetic macular edema (DME).

DESIGN

Retrospective cohort study.

PARTICIPANTS

Patients receiving ranibizumab injections for centre-involving DME in a National Health Service setting.

METHODS

The Moorfields OpenEyes database was used to study eyes with DME treated with ranibizumab from October 2013 to November 2015 at the Moorfields City Road, Ealing, Northwick Park, and St George's Hospital sites. Only eyes receiving a minimum of 3 injections and completing 12 months of follow-up were included. If both eyes received treatment, the first eye treated was analyzed. When both eyes received initial treatment simultaneously, random number tables were used to select the eye for analysis. HbA1c was tested at the initiation of ranibizumab treatment. Multivariate regression analysis was used to identify relationships between HbA1c and the outcome measures.

OUTCOMES

The primary outcome was change in visual acuity (VA) Early Treatment of Diabetic Retinopathy study (ETDRS) letters. The secondary outcomes were change in central subfield thickness (CSFT) and macular volume (MV), as well as number of injections in year 1.

RESULTS

Three hundred and twelve eyes of 312 patients were included in the analysis. HbA1c was not related to change in VA (p = 0.577), change in CSFT (p = 0.099), change in MV (p = 0.082), or number of injections in year 1 (p = 0.859).

CONCLUSIONS

HbA1c is not related to functional or anatomical outcomes at 1 year in DME treated with ranibizumab.

Correction: Individual and temporal variability of the retina after chronic bilateral common carotid artery occlusion (BCCAO)

[This corrects the article DOI: 10.1371/journal.pone.0193961.].

The TetO rat as a new translational model for type 2 diabetic retinopathy by inducible insulin receptor knockdown

AIMS/HYPOTHESIS

Although the renin-angiotensin system plays an important role in the progression of diabetic retinopathy, its influence therein has not been systematically evaluated. Here we test the suitability of a new translational model of diabetic retinopathy, the TetO rat, for addressing the role of angiotensin-II receptor 1 (AT1) blockade in experimental diabetic retinopathy.

METHODS

Diabetes was induced by tetracycline-inducible small hairpin RNA (shRNA) knockdown of the insulin receptor in rats, generating TetO rats. Systemic treatment consisted of an AT1 blocker (ARB) at the onset of diabetes, following which, 4-5 weeks later the retina was analysed in vivo and ex vivo. Retinal function was assessed by Ganzfeld electroretinography (ERG).

RESULTS

Retinal vessels in TetO rats showed differences in vessel calibre, together with gliosis. The total number and the proportion of activated mononuclear phagocytes was increased. TetO rats presented with loss of retinal ganglion cells (RGC) and ERG indicated photoreceptor malfunction. Both the inner and outer blood-retina barriers were affected. The ARB treated group showed reduced gliosis and an overall amelioration of retinal function, alongside RGC recovery, whilst no statistically significant differences in vascular and inflammatory features were detected.

CONCLUSIONS/INTERPRETATION

The TetO rat represents a promising translational model for the early neurovascular changes associated with type 2 diabetic retinopathy. ARB treatment had an effect on the neuronal component of the retina but not on the vasculature.

Abstract 652: dTGR: A New Rat Model For Systemic Hypertensive Retinopathy

Retinal vascular alterations represent an important but understudied form of microvascular target endorgan damage (TOD). To understand the pathomechanisms underlying hypertensive retinopathy, we used a double transgenic rat model (dTGR) established for TOD, which expresses both the rat and human RAS. Purpose of the study is to assess whether systemic hypertension affects retinal structure and function similar to the characteristic pathology in humans.

We investigated the retinal phenotype by using immunohistochemistry of retinal whole mount preparations or sagittal sections, qPCR as well as functional analysis by Ganzfeld and pattern electro-retinography (ERG).

Whole mount preparations revealed focal avascular areas, pathological vessels with irregularities in shape and diameter as well as neovascular tufts in dTGR rats compared to control animals. In sagittal sections we detected a loss of retinal ganglion cells. GFAP staining revealed activation of astrocytes in the ganglion cell layer (GCL) and astrocytosis of the optic nerve. VEGF-positive staining could be detected in the ganglion cell layer (GCL) and the inner nuclear layer (INL).

To further substantiate the loss of ganglion cells detected in immunohistochemistry and to obtain a correlated functional analysis, pattern ERG were recorded. By using a stimulation with different pattern sizes (15° and 5-7°) at 2.4hz of the black and white checkerboard we showed that the positive component after about 50ms (P50) of the pattern ERG was significantly smaller in dTGR compared to control rats at 5-7° pattern size whereas the P50 at 15° remained unchanged. This indicates a loss of ganglion cells in the retina.

qPCR revealed a non-detectable local renin expression, increase in MCP1 and sFLT1 expression and decrease in the expression of tight-junction proteins claudin-1 and occludin.

Thus we present a first animal model for hypertensive retinopathy showing functional and structural alterations of the retina. Differential gene expression analysis suggests a strong local inflammatory response, loss of the blood/retina barrier and surprisingly low activity of the local renin-angiotensin-system. Further studies are warranted to investigate the local pathomechanisms.