Double heterozygous pathogenic germline APC and MSH2 variants in a 16-year-old female diagnosed with colorectal cancer.
Elena Maccaroni, Riccardo Bacalini, Alessia Lancianese et al.
✦ AI-curated · Sources linked
Case in brief
A 16-year-old female presented with multiple colonic polyps and invasive colorectal carcinoma. Genetic testing identified heterozygous pathogenic variants in both APC and MSH2, consistent with the genetic basis of familial adenomatous polyposis and Lynch syndrome. The report describes the coexistence of these findings in one patient and suggests personalized follow-up and surveillance; the abstract does not provide further details on treatment or outcome.
What made this case unusual
The patient had an MSH2-EPCAM large rearrangement together with a frameshift APC pathogenic variant, an unusual combination associated with both hereditary syndromes.
Diagnostic / clinical pearl
In a young patient with colorectal cancer and multiple polyps, comprehensive genetic testing can identify pathogenic variants in more than one hereditary cancer syndrome.