Effects of plaque brachytherapy and proton beam radiotherapy on prognostic testing: a comparison of uveal melanoma genotyped by microsatellite analysis

Thornton, Sophie ORCID: 0000-0001-7693-7279, Coupland, Sarah E ORCID: 0000-0002-1464-2069, Heimann, Heinrich, Hussain, Rumana ORCID: 0000-0001-8208-5009, Groenewald, Carl, Kacperek, Andrzej, Damato, Bertil, Taktak, Azzam, Eleuteri, Antonio ORCID: 0000-0003-0718-6672 and Kalirai, Helen ORCID: 0000-0002-4440-2576 (2020) Effects of plaque brachytherapy and proton beam radiotherapy on prognostic testing: a comparison of uveal melanoma genotyped by microsatellite analysis. BRITISH JOURNAL OF OPHTHALMOLOGY, 104 (10). pp. 1462-1466. ISSN 0007-1161, 1468-2079

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Abstract

<h4>Background/aims</h4>Proton beam radiotherapy and plaque brachytherapy are commonly applied in primary uveal melanoma (UM); however, their effect on chromosome 3 classification of UM by microsatellite analysis (MSA) for prognostication purposes is unknown, where the tumour is sampled post-irradiation. This study examined the prognostic accuracy of genotyping UM biopsied before or after administration of radiotherapy, by MSA.<h4>Methods</h4>407 UM patients treated at the Liverpool Ocular Oncology Centre between January 2011 to December 2017, were genotyped for chromosome 3 by MSA; 172 and 176 primary UM were sampled prior to and post irradiation, respectively.<h4>Results</h4>Genotyping by MSA was successful in 396/407 (97%) of UM samples (196 males, 211 females; median age of 61 years (range 12 to 93) at primary treatment). There was no demonstrable association between a failure of MSA to produce a chromosome 3 classification and whether radiation was performed pre-biopsy or post-biopsy with an OR of 0.96 (95% CI 0.30 to 3.00, p=0.94). There was no evidence of association (measured as HRs) between risk of metastatic death and sampling of a primary UM before administration of radiotherapy (HR 1.1 (0.49 to 2.50), p=0.81). Monosomy 3 (HR 12.0 (4.1 to 35.0), p<0.001) was significantly associated with increased risk of metastatic death.<h4>Conclusions and relevance</h4>This study revealed that successful genotyping of UM using MSA is possible, irrespective of irradiation status. Moreover, we found no evidence that biopsy prior to radiotherapy increases metastatic mortality.

Item Type:	Article
Uncontrolled Keywords:	Chromosomes, Human, Pair 3, Humans, Melanoma, Uveal Neoplasms, DNA, Neoplasm, Prognosis, Brachytherapy, Proportional Hazards Models, Follow-Up Studies, Microsatellite Repeats, Genotype, Adolescent, Adult, Aged, Aged, 80 and over, Middle Aged, Child, Female, Male, Genotyping Techniques, Proton Therapy, Biomarkers, Tumor, Uveal Melanoma
Depositing User:	Symplectic Admin
Date Deposited:	21 Feb 2020 10:17
Last Modified:	03 Apr 2025 09:18
DOI:	10.1136/bjophthalmol-2019-315363
Related Websites:	Author Publisher
URI:	https://livrepository.liverpool.ac.uk/id/eprint/3074859