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

Delays between Uveal Melanoma Diagnosis and Treatment Increase the Risk of Metastatic Death

PURPOSE

To investigate if the interval between diagnosis and treatment of posterior uveal melanoma (UM) is associated with metastatic death.

DESIGN

Retrospective, single-center cohort study.

PARTICIPANTS

A total of 1145 patients consecutively diagnosed with posterior UM at St. Erik Eye Hospital, Stockholm, Sweden, from 2012 to 2022, with recorded dates of diagnosis and primary treatment. This cohort represents 81% of all diagnosed patients in Sweden during this period.

METHODS

Data on the interval between diagnosis and treatment were collected for all patients. Its prognostic importance was examined with univariate and multivariate competing risks regressions, and cumulative incidence analyses.

MAIN OUTCOME MEASURES

Incidence of metastatic death (UM mortality) for patients with prompt (< 1 month from diagnosis) versus delayed treatment (≥ 1 month) and subdistribution hazard ratios (exp(βj)) for every additional 10-day delay in treatment.

RESULTS

The mean interval between diagnosis and treatment was 34 days (SD, 56, range, 0-932). Patients treated promptly had larger tumors at diagnosis, but there were no differences in patient age, tumor distance to the optic disc, rates of ciliary body involvement (CBI) or extraocular extension (EXE), or symptom duration before diagnosis. Those who were treated more than 1 month after diagnosis had greater UM mortality in American Joint Committee on Cancer (AJCC) stage II and III. In stage I, UM mortality for delayed treatment was lower for the first 10 years, followed by a marked spike in the 11th year. In multivariate competing risks regressions of all 1145 patients with tumor diameter, thickness, CBI, and EXE as covariates, the risk for UM mortality increased with 1% for every additional 10-day delay in treatment (exp(βj) 1.01). Among 355 patients treated with enucleation, this delay was associated with UM mortality, independent of AJCC stage, cytomorphology, and level of immunohistochemical BAP-1 expression.

CONCLUSIONS

Increasing time between diagnosis and treatment of UM is associated with a higher risk of metastatic death. These results challenge a central concept in the understanding of metastatic progression and may indicate the existence of late metastatic seeding. They also underscore the importance of prompt treatment. Validation in independent cohorts is recommended.

FINANCIAL DISCLOSURE(S)

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Overrepresentation of human epidermal growth factor receptor 2 positive- and Luminal B breast cancer metastases in the eyes and orbit

BACKGROUND

Breast cancer is the most common cancer to spread to the choroid and orbit. Depending on a set of prognostic and predictive biomarkers, breast cancer can be divided into at least four distinct subtypes with separate treatment and clinical course.

SUBJECTS

Thirty-two patients with metastases to the eye and periocular area diagnosed between 2005 and 2020, of which 11 also had primary tumour tissue available. Expression levels of oestrogen- (ER) and progesterone receptors (PR), Human epidermal growth factor receptor 2 (HER2) and the proliferation marker Ki67 were analysed.

RESULTS

Twenty-five of 32 patients (78%) had a history of primary breast cancer, whereas the remaining 7 (22%) presented with metastatic disease. Of available metastases, 83% were positive for ER, 37% for PR, 54% for HER2, and 50% for Ki67. Metastases had significantly lower proportions of PR-positive cells than primary tumours, and the distribution of the Luminal A, Luminal B, HER2 enriched and triple-negative subtypes differed between primary tumours and metastases (P = 0.012): Six of 9 patients with a full set of biomarkers on both primary tumours and metastases switched subtype (67%), and 23 of 32 metastases (77%) were of the Luminal B subtype.

CONCLUSIONS

Nearly 4 in 5 breast cancer metastases in the eyes and orbit are of the Luminal B subtype, and a majority are HER2 positive. The breast cancer subtype frequently switches between primary tumours and metastases. Future studies should evaluate these results in larger cohorts.

The prognostic implication of visual acuity at the time of uveal melanoma diagnosis

BACKGROUND

Visual outcomes after primary tumour treatment of uveal melanoma (UM) have been investigated repeatedly. This study evaluates the correlation between best-corrected visual acuity (BCVA) before treatment with clinicopathological factors and patient survival.

SUBJECTS/METHODS

Pre-treatment BCVA was examined in relation to tumour dimensions and location, and survival in a retrospective cohort of 1809 patients who underwent plaque brachytherapy. BCVA was also correlated to tumour histological factors in a second cohort of 137 enucleated eyes.

RESULTS

The mean BCVA of the tumour eye prior to plaque brachytherapy was LogMAR 0.42 (SD 0.46). Patients with low BCVA (LogMAR ≥ 1.00) did not differ in age (p = 0.19) and had similar frequency of ciliary body involvement (p = 0.99) but had tumours with greater apical thickness (p < 0.0001), greater diameter (p < 0.0001) and shorter distance to the optic disc and fovea (p < 0.0001). There were no significant relations between low BCVA and any of 13 examined tumour histological factors at a Bonferroni-corrected significance level (p > 0.004). Patients with low BCVA had greater incidence of UM-related mortality in competing risk analysis (p = 0.0019) and shorter overall survival (p < 0.0001). Low BCVA was also associated with increased hazard ratio (HR) for UM-related mortality in univariate analysis (HR 1.5, 95% confidence interval 1.2 to 1.9), but not in multivariate analysis with tumour size and location as covariates.

CONCLUSIONS

UM patients with low BCVA before primary tumour treatment have a worse prognosis, likely related to increased tumour dimensions. Future studies should examine the prognostic significance of BCVA in relation to macula-involving retinal detachment and genetic factors.

USP2 promotes cell proliferation and metastasis in choroidal melanoma via stabilizing Snail

BACKGROUND

Choroidal melanoma (CM) is an intraocular tumor that arises from melanocytes. While ubiquitin-specific protease 2 (USP2) modulates the progression of numerous diseases, its role in CM is not known. This study aimed to determine the role of USP2 in CM and elucidate its molecular mechanisms.

METHODS

MTT, Transwell, and wound-scratch assays were used to investigate the function of USP2 in the proliferation and metastasis of CM. Western blotting and qRT-PCR were used to analyze the expression of USP2, Snail, and factors associated with the epithelial-mesenchymal transition (EMT). The relationship between USP2 and Snail was explored by co-immunoprecipitation and in vitro ubiquitination assays. A nude mouse model of CM was established for verifying the role of USP2 in vivo.

RESULTS

USP2 overexpression promoted proliferation and metastasis, and induced the EMT in CM cells in vitro, while specific inhibition of USP2 by ML364 produced the opposite effects. ML364 also suppressed CM tumor growth in vivo. Mechanistically, USP2 is known to deubiquitinate Snail, stabilizing the latter through the removal of its K48 poly-ubiquitin chains. However, a catalytically inactive form of USP2 (C276A) had no effect on Snail ubiquitination and failed to increase Snail protein expression. The C276A mutant was also unable to promote CM cell proliferation, migration, and invasion, as well as EMT progression. Furthermore, Snail overexpression partly counteracted the effects of ML364 on proliferation and migration, while rescuing the effects of the inhibitor on the EMT.

CONCLUSIONS

The findings demonstrated that USP2 modulated CM development through the stabilization of Snail and suggest that USP2 may be a useful target for the development of novel treatments for CM.

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.

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.

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.

Estimation of the timing of BAP1 mutation in uveal melanoma progression

Uveal melanoma is the most common primary intraocular malignancy. A vast majority of metastasizing tumors have mutations in the BAP1 gene. Here, we investigate the spatiotemporal timing of these mutations. The size of 177 uveal melanomas and 8.3 million individual tumor cells was measured. BAP1 sequencing results and BAP1 IHC were available and for 76 (43%) and 101 (57%) of these, respectively. Tumors with a BAP1 mutation had significantly larger volume (2109 vs. 1552 mm³, p = 0.025). Similarly, tumor cells with loss of BAP1 protein expression had significantly larger volume (2657 vs. 1593 μm³, p = 0.027). Using observations of the time elapsed between mitoses, the BAP1 mutation was calculated to occur when the primary tumor had a size of a few malignant cells to 6 mm³, 0.5 to 4.6 years after tumor initiation and at least 9 years before diagnosis. We conclude that BAP1 mutations occur early in the growth of uveal melanoma, well before the average tumor is diagnosed. Its timing coincides with the seeding of micrometastases.

Intratumor Heterogeneity in Uveal Melanoma BAP-1 Expression

Malignant tumors are rarely homogenous on the morphological, genome, transcriptome or proteome level. In this study, we investigate the intratumor heterogeneity of BAP-1 expression in uveal melanoma with digital image analysis of 40 tumors. The proportion of BAP-1 positive cells was measured in full tumor sections, hot spots, cold spots and in scleral margins. The mean difference between hot spots and cold spots was 41 percentage points (pp, SD 29). Tumors with gene expression class 1 (associated with low metastatic risk) and 2 (high metastatic risk) had similar intratumor heterogeneity. Similarly, the level of intratumor heterogeneity was comparable in tumors from patients that later developed metastases as in patients that did not. BAP-1 measured in any tumor region added significant prognostic information to both American Joint Committee on Cancer (AJCC) tumor size category (p ≤ 0.001) and gene expression class (p ≤ 0.04). We conclude that there is substantial intratumor heterogeneity in uveal melanoma BAP-1 expression. However, it is of limited prognostic importance. Regardless of region, analysis of BAP-1 expression adds significant prognostic information beyond tumor size and gene expression class.