Immunohistochemical determination of mismatch repair gene product in colorectal carcinomas in a young indigenous African cohort.
Journal
South African journal of surgery. Suid-Afrikaanse tydskrif vir chirurgie
ISSN: 2078-5151
Titre abrégé: S Afr J Surg
Pays: South Africa
ID NLM: 2984854R
Informations de publication
Date de publication:
Mar 2022
Mar 2022
Historique:
entrez:
22
4
2022
pubmed:
23
4
2022
medline:
26
4
2022
Statut:
ppublish
Résumé
Colorectal cancer (CRC) in the indigenous African population of South Africa is uncommon (age standardised incidence rates of 11.29 for males and 7.27/100 000 for females) and tends to occur at a young age. Lynch syndrome (LS), an inherited mismatch repair (MMR) gene abnormality, accounts for 3-4% of newly diagnosed CRCs in high incidence areas. There is some evidence that the contribution of an MMR abnormality to the overall CRC burden may be increased in low incidence areas. We aimed to determine the prevalence of MMR deficiency in an indigenous African population. A cohort of 66 self-declared indigenous African patients, less than 50 years of age at diagnosis with CRC was identified from clinical and pathological records. The original histopathology was reviewed to confirm the diagnosis and features suggestive of MMR abnormality determined (pushing edge, mucinous, lymphocytic infiltration, Crohn's like reaction). Where sufficient tissue was available, samples were sectioned and stained for the four MMR proteins. Histopathological examination confirmed adenocarcinoma in 31 individuals. At least one feature suggestive of MMR was identified in 22 of these specimens. Twenty-seven cases were stained for all four MMR proteins using standard immunohistochemistry (IHC). MMR deficiency was found in 37% ( MMR deficiency was common in colorectal carcinomas in the older patients in this cohort, but very young indigenous Africans CRCs do not appear to result from mismatch repair gene mutations.
Sections du résumé
BACKGROUND
BACKGROUND
Colorectal cancer (CRC) in the indigenous African population of South Africa is uncommon (age standardised incidence rates of 11.29 for males and 7.27/100 000 for females) and tends to occur at a young age. Lynch syndrome (LS), an inherited mismatch repair (MMR) gene abnormality, accounts for 3-4% of newly diagnosed CRCs in high incidence areas. There is some evidence that the contribution of an MMR abnormality to the overall CRC burden may be increased in low incidence areas. We aimed to determine the prevalence of MMR deficiency in an indigenous African population.
METHODS
METHODS
A cohort of 66 self-declared indigenous African patients, less than 50 years of age at diagnosis with CRC was identified from clinical and pathological records. The original histopathology was reviewed to confirm the diagnosis and features suggestive of MMR abnormality determined (pushing edge, mucinous, lymphocytic infiltration, Crohn's like reaction). Where sufficient tissue was available, samples were sectioned and stained for the four MMR proteins.
RESULTS
RESULTS
Histopathological examination confirmed adenocarcinoma in 31 individuals. At least one feature suggestive of MMR was identified in 22 of these specimens. Twenty-seven cases were stained for all four MMR proteins using standard immunohistochemistry (IHC). MMR deficiency was found in 37% (
CONCLUSION
CONCLUSIONS
MMR deficiency was common in colorectal carcinomas in the older patients in this cohort, but very young indigenous Africans CRCs do not appear to result from mismatch repair gene mutations.
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Pagination
28-33Informations de copyright
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