Recent developments in oncology have led to a better molecular and cellular understanding of cancer, and the introduction of novel therapies. Conjunctival melanoma (CoM) is a rare but potentially ...devastating disease. A better understanding of CoM, leading to the development of novel therapies, is urgently needed.
CoM is characterized by mutations that have also been identified in cutaneous melanoma, e.g. in BRAF, NRAS and TERT. These mutations are distinct from the mutations found in uveal melanoma (UM), affecting genes such as GNAQ, GNA11, and BAP1. Targeted therapies that are successful in cutaneous melanoma may therefore be useful in CoM.
A recent breakthrough in the treatment of patients with metastatic cutaneous melanoma was the development of immunotherapy. While immunotherapy is currently sparsely effective in intraocular tumours such as UM, the similarities between CoM and cutaneous melanoma (including in their immunological tumour micro environment) provide hope for the application of immunotherapy in CoM, and preliminary clinical data are indeed emerging to support this use.
This review aims to provide a comprehensive overview of the current knowledge regarding CoM, with a focus on the genetic and immunologic understanding. We elaborate on the distinct position of CoM in contrast to other types of melanoma, and explain how new insights in the pathophysiology of this disease guide the development of new, personalized, treatments.
•CoM is a rare but potentially deadly extraocular tumour, with a rising incidence.•Genetic mutations in CoM resemble those in cutaneous melanoma, but not UM.•The presence of immune cells is important for the development and control of CoM.•Targeted therapy and checkpoint inhibitors can be applied to treat CoM patients.
To relate conjunctival melanoma characteristics to local control.
Retrospective, registry-based interventional study with data gathered from 10 ophthalmic oncology centres from 9 countries on 4 ...continents. Conjunctival melanoma patients diagnosed between January 2001 and December 2013 were enrolled in the study. Primary treatments included local excision, excision with cryotherapy and exenteration. Adjuvant treatments included topical chemotherapy, brachytherapy, proton and external beam radiotherapy (EBRT). Cumulative 5-year and 10-year Kaplan-Meier local recurrence rates were related to clinical and pathological T-categories of the eighth edition of the American Joint Committee on Cancer (AJCC) staging system.
288 patients had a mean initial age of 59.7±16.8 years. Clinical T-categories (cT) were cT1 (n=218,75.7%), cT2 (n=34, 11.8%), cT3 (n=15, 5.2%), cTx (n=21,7.3%) with no cT4. Primary treatment included local excision (n=161/288, 55.9%) followed by excision biopsy with cryotherapy (n=108/288, 37.5%) and exenteration (n=5/288, 1.7%). Adjuvant therapies included topical mitomycin (n=107/288, 37.1%), plaque-brachytherapy (n=55/288, 19.1%), proton-beam (n=36/288, 13.5%), topical interferon (n=20/288, 6.9%) and EBRT (n=15/288, 5.2%). Secondary exenteration was performed (n=11/283, 3.9%). Local recurrence was noted in 19.1% (median=3.6 years). Cumulative local recurrence was 5.4% (3.2-8.9%), 19.3% (14.4-25.5%) and 36.9% (26.5-49.9%) at 1, 5 and 10 years, respectively. cT3 and cT2 tumors were twice as likely to recur than cT1 tumours, but only cT3 had statistically significantly greater risk of local recurrence than T1 (p=0.013). Factors such as tumour ulceration, plica or caruncle involvement and tumour thickness were not significantly associated with an increased risk of local recurrence.
This multicentre international study showed that eighth edition of AJCC tumour staging was related to the risk of local recurrence of conjunctival melanoma after treatment. The 10-year cumulative local recurrence remains high despite current management.
Individuals with gray, blue, or green eyes have a higher chance of developing uveal melanoma (UM) than those with brown eyes. We wondered whether iris pigmentation might be related not only to ...predisposition to UM but also to its behavior; therefore, we compared the clinical, histopathologic, and genetic characteristics of UM between eyes with different colors.
We determined iris color in a large cohort of patients enucleated for UM. Clinical and histopathologic tumor characteristics, chromosome status, and survival were compared among 3 groups on the basis of iris color.
A total of 412 patients with choroidal/ciliary body UM, who had undergone primary enucleation at the Leiden University Medical Center, Leiden, The Netherlands, between 1993 and 2019, were divided into 3 groups based on iris color: gray/blue, green/hazel, and brown. The validation cohort included 934 patients with choroidal/ciliary body UM treated at Wills Eye Hospital (WEH).
Comparison of clinical, histopathologic, and genetic characteristics of UM in patients with different iris colors.
Melanoma-related survival in UM patients, divided over 3 iris color groups, in relation to the tumor’s chromosome 3 and 8q status.
Moderate and heavy tumor pigmentations were especially seen in eyes with a brown iris (P < 0.001). Survival did not differ between patients with different iris colors (P = 0.27); however, in patients with a light iris, copy number changes in chromosome 3 and 8q had a greater influence on survival than in patients with a dark iris. Likewise, chromosome 3 and chromosome 8q status affected survival more among patients with lightly pigmented tumors than in patients with heavily pigmented tumors. The WEH cohort similarly showed a greater influence of chromosome aberrations in light-eyed individuals.
Although iris color by itself did not relate to UM-related survival, chromosome 3 and 8q aberrations had a larger influence on survival in patients with a light iris than those with a brown iris. This suggests a synergistic effect of iris pigmentation and chromosome status in the regulation of oncogenic behavior of UM. Iris color should be taken into consideration when calculating a patient's risk for developing metastases.
IMPORTANCE: Eye cancer staging systems used for standardizing patient care and research need to be validated. OBJECTIVE: To evaluate the accuracy of the eighth edition of the American Joint Committee ...on Cancer (AJCC) Cancer Staging Manual in estimating metastatis and mortality rates of conjunctival melanoma. DESIGN, SETTING, AND PARTICIPANTS: This international, multicenter, registry-based case series pooled data from 10 ophthalmic oncology centers from 9 countries on 4 continents. A total of 288 patients diagnosed with conjunctival melanoma from January 1, 2001, to December 31, 2013, were studied. Data analysis was performed from July 7, 2018, to September 11, 2018. INTERVENTIONS: Treatments included excision biopsy, cryotherapy, topical chemotherapy, radiation therapy, enucleation, and exenteration. MAIN OUTCOMES AND MEASURES: Metastasis rates and 5-year and 10-year Kaplan-Meier mortality rates according to the clinical T categories and subcategories of the eighth edition of the AJCC Cancer Staging Manual. RESULTS: A total of 288 eyes from 288 patients (mean SD age, 59.7 16.8 years; 147 51.0% male) with conjunctival melanoma were studied. Clinical primary tumors (cT) were staged at presentation as cT1 in 218 patients (75.7%), cT2 in 34 (11.8%), cT3 in 15 (5.2%), and cTx in 21 (7.3%). There were no T4 tumors. Pathological T categories (pT) were pTis in 43 patients (14.9%), pT1 in 169 (58.7%), pT2 in 33 (11.5%), pT3 in 12 (4.2%), and pTx in 31 (10.8%). Metastasis at presentation was seen in 5 patients (1.7%). Metastasis during follow-up developed in 24 patients (8.5%) after a median time of 4.3 years (interquartile range, 2.9-6.0 years). Of the 288 patients, 29 died (melanoma-related mortality, 10.1%) at a median time of 5.3 years (interquartile range, 1.8-7.0 years). The cumulative rates of mortality among patients with cT1 tumors were 0% at 1 year, 2.5% (95% CI, 0.7%-7.7%) at 5 years, and 15.2% (95% CI, 8.1%-27.4%) at 10 years of follow-up; among patients with cT2 tumors, 0% at 1 year, 28.6% (95% CI, 12.9%-58.4%) at 5 years, and 43.6% (95% CI, 19.6%-77.9%) at 10 years of follow-up; and among patients with cT3 tumors, 21.1% (95% CI, 8.1%-52.7%) at 1 year of follow-up and 31.6% (95% CI, 13.5%-64.9%) at 5 years of follow-up. Patients with cT2 and cT3 tumors had a significantly higher cumulative mortality rate compared with those presenting with cT1 tumors (log-rank P < .001). Patients with ulcerated melanomas had significantly higher risk of mortality (hazard ratio, 7.58; 95% CI, 1.02-56.32; P = .04). CONCLUSIONS AND RELEVANCE: This multicenter, international, collaborative study yielded evidence that the conjunctival melanoma staging system in the eighth edition of the AJCC Cancer Staging Manual can be used to accurately estimate metastasis and mortality rates. These findings appear to support the use of AJCC staging as a tool for patient care and research.
To study the feasibility and diagnostic value of vascular imaging using optical coherence tomography (OCT)-angiography (OCTA) of melanocytic lesions of the conjunctiva and iris.
Cross-sectional ...study.
Twenty-five patients with an untreated conjunctival lesion (5 melanoma, 13 nevus, 7 primary acquired melanosis PAM) and 52 patients with an untreated iris lesion (10 melanoma, 42 nevus) were included. Patients were imaged using a commercially available OCTA device, with the addition of an anterior segment lens and manual focussing. Tumor vessel presence, vascular patterns and vascular density were assessed.
Good OCTA images were obtained in 18 of 25 conjunctival lesions and 42 of 52 iris lesions. Failure was caused by lack of patient cooperation, an unfavorable location, or mydriasis. In all imaged conjunctival lesions and 77% of iris lesions, vascular structures were detected. Conjunctival melanoma and nevi demonstrated the same intralesional tortuous patterns, whereas vasculature in eyes with PAM was similar to normal conjunctiva. Both iris melanoma and nevi demonstrated tortuous patterns, distinct from the radially oriented normal iris vasculature.
Optical coherence tomography angiography (OCTA) allows for noninvasive imaging of the vasculature in melanocytic lesions of the conjunctiva and iris. Good image quality depends highly on patient cooperation and lesion characteristics. Differentiation of benign and malignant lesions was not possible. New software is called for to improve image acquisition and analysis.
Increased angiogenesis is associated with a higher metastasis- and mortality rate in uveal melanoma (UM). Recently, it was demonstrated that genetic events, such as 8q-gain and BAP1-loss, influence ...the level of immune infiltrate. We aimed to determine whether genetic events, and specific cytokines, relate to angiogenesis in UM. Data from UM patients who underwent enucleation between 1999 and 2008 were analysed. Microvascular density (MVD) and the presence of infiltrating immune cells were determined with immunohistochemistry (IHC) and immunofluorescence in 43 cases. Chromosome status, BAP1 IHC and mRNA expression of angiogenesis-related genes were known in 54 cases. Tumours with monosomy 3/BAP1-loss showed a higher MVD compared to tumours with disomy 3/normal BAP1 expression (
= 0.008 and
= 0.004, respectively). Within BAP1-positive lesions (
= 20), 8q-gain did not relate to MVD (
= 0.51). A high MVD was associated with an increased expression of angiopoietin 2 (ANGPT2) (
= 0.041), Von Willebrand Factor (VWF) (
= 0.010), a decreased expression of vascular endothelial growth factor B (VEGF-B) (
= 0.024), and increased numbers of tumour-infiltrating macrophages (CD68+,
= 0.017; CD68+CD163+,
= 0.031) and lymphocytes (CD4+,
= 0.027). Concluding, vascular density of UM relates to its genetic profile: Monosomy 3 and BAP1-loss are associated with an increased MVD, while an early event (gain of 8q) is not independently related to MVD, but may initiate a preparation phase towards development of vessels. Interestingly, VEGF-B expression is decreased in UM with a high MVD.
To compare retinal vessel oxygenation in eyes with an untreated choroidal nevus or choroidal melanoma.
The affected and fellow eye of patients with an untreated choroidal nevus (n = 42) or choroidal ...melanoma (n = 45) were investigated using noninvasive retinal oximetry (Oxymap T1). Oxygen saturation of arterioles (ArtSat) and venules (VenSat) was determined, together with the arteriovenous difference (AV-difference).
In choroidal nevus patients, retinal oximetry did not differ between the affected and fellow eye: the mean ArtSat was 94.5% and 94.2% (P = 0.56), the VenSat was 60.5% and 61.3% (P = 0.35), and the AV-difference was 34.0% and 32.9% (P = 0.18), respectively. In choroidal melanoma patients, alterations were detected: the mean ArtSat was 94.8% and 93.2% (P = 0.006), the VenSat was 58.0% and 60.0% (P = 0.014), and the AV-difference was 36.8% and 33.2% (P < 0.001), respectively. The largest increase in AV-difference was observed between the retinal halves without the lesion in melanoma eyes compared with the corresponding half in the fellow eye (37.5% vs. 32.1%, P < 0.001).
Although retinal oximetry was not significantly altered in eyes with a choroidal nevus, eyes with choroidal melanoma showed an increased ArtSat and decreased VenSat, leading to an increased AV-difference. These changes may be caused by inflammation and a higher metabolism, with larger oxygen consumption, leading to altered blood flow and intraocular oxygen relocation.
Hypoxia-inducible factor 1-alpha (HIF1a) and its regulator von Hippel-Lindau protein (VHL) play an important role in tumour ischemia. Currently, drugs that target HIF1a are being developed to treat ...malignancies. Although HIF1a is known to be expressed in uveal melanoma (UM), it is as yet unknown which factors, such as tumour size or genetics, determine its expression. Therefore, we aimed to determine which tumour characteristics relate to HIF1a expression in UM. Data from 64 patients who were enucleated for UM were analysed. Messenger RNA (mRNA) expression was determined with the Illumina HT-12 v4 chip. In 54 cases, the status of chromosomes 3 and 8q, and
-associated protein 1 (BAP1) protein expression (immunohistochemistry) were determined. Findings were corroborated using data of 80 patients from the Cancer Genome Atlas (TCGA) study. A significantly increased expression of HIF1a, and a decreased expression of VHL were associated with monosomy 3/loss of BAP1 expression. The relationship between BAP1 loss and HIF1a expression was independent of chromosome 3. The largest basal diameter and tumour thickness showed no relationship with HIF1a. HIF1a expression related to an increased presence of infiltrating T cells and macrophages. From this study, we conclude that HIF1a is strongly related to tumour genetics in UM, especially to loss of BAP1 expression, and less to tumour size. Tumour ischemia is furthermore related to the presence of an inflammatory phenotype.
Purpose
In primary conjunctival melanoma (CoM), one of the characteristics that is associated with an increased risk of metastases and death is a lack of tumour pigmentation. The aim of this study ...was to investigate whether the degree of pigmentation of CoM recurrences relates similarly to clinical outcome.
Methods
A data set of 177 patients with a CoM recurrence from the Wills Eye Hospital (USA) and the Leiden University Medical Center (The Netherlands) was analysed. The relation between clinical tumour pigmentation of the recurrences, the characteristics of the primary lesions and clinical outcome was investigated.
Results
In 117 (66%) of 177 patients with a CoM recurrence, tumour pigmentation was known: 71 patients (61%) had recurrences with low pigmentation. Primary lesions had low pigmentation in 39% of cases, which is significantly different (
p
= 0.001). However, low tumour pigmentation of recurrences correlated with low tumour pigmentation of the primary lesion (
p
< 0.001). No association was observed between pigmentation of the recurrences and iris colour (
p
= 0.66). Low pigmentation of the recurrences was not significantly associated with an increased risk for metastases (HR 1.96,
p
= 0.12) or death (HR 1.79,
p
= 0.27), whereas primary tumours with low pigmentation did show a greater risk for metastases (HR 2.82,
p
= 0.016) and death (HR 2.90,
p
= 0.037).
Conclusions
CoM recurrences are more often lightly pigmented compared to primary lesions. A correlation exists between the degree of pigmentation of primary and recurrent lesions, but recurrences can appear with any degree of pigmentation. Unlike primary CoM, the level of pigmentation of CoM recurrences is not related to metastasis or death.
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