Exploring the links between protein deficiencies and the development of Lynch syndrome
In a paper published in the Australasian Journal of Dermatology, researchers at the University of Melbourne have explored features of skin lesions that can be used to identify which should be tested for a lack of the mismatch repair protein (MMR). The absence of MMR protein in skin lesions can be used to identify people with Lynch syndrome.
(Picture: Associate Professor Daniel Buchanan in his lab at the University of Melbourne Centre for Cancer Research)
Lynch syndrome is a genetic disease that can lead to the development of cancer, particularly bowel cancer. It has been found that the lack of certain proteins in skin lesions can provide a warning sign for the development of Lynch syndrome.
The expression of MMR proteins was determined by immunohistochemical staining (IHC) ¬– staining selective antigens with fluorescence dyes – which has been reported to be a sensitive tool screening tool for identification of MMR.
The skin lesions tested were sourced from a single pathology practice in Brisbane, Australia. Lesions were investigated alongside features including age at diagnosis, sex, lesion type and site on body, that may differentiate those that are MMR-deficient and MMR-proficient.
MMR deficiency was reported in 30.7% of the lesions tested, most common in sebaceous adenomas. Approximately two-thirds of the sebaceous adenomas, sebaceomas and sebaceous carcinomas combined on the trunk or limbs were MMR-deficient, compared with only 23.2% of lesions in head or neck.
This research has been the largest study in sebaceous skin lesions to date, and found that commonly collected clinico-pathological features were not shown to be strong predictors to identify patients or sebaceous lesions that should be tested for MMR deficiency.
Associate Professor Daniel Buchanan, of the University of Melbourne Centre for Cancer Research and Department of Clinical Pathology said: “The challenge remains for clinicians and pathologists to determine which sebaceous skin lesions should be tested for MMR-deficiency.
“This study has highlighted that further genotype-phenotype correlation in sebaceous neoplasia is essential to improve decision making for MMR testing and its clinical consequences.”