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Copyright ©The Author(s) 2016.
World J Gastroenterol. Feb 7, 2016; 22(5): 1736-1744
Published online Feb 7, 2016. doi: 10.3748/wjg.v22.i5.1736
Table 1 Clinicopathologic and molecular differences between young-onset and late-onset colorectal cancer
Clinical and molecular characteristicsYoung-onset CRC(50 yr)Late-onset CRC(> 50 yr)
Proximal colonX
Distal colon and rectumX
Synchronous and metachronous CRCX
Later stage at diagnosis (stage III/IV)X
Mucinous/signet ring and poorly differentiated featuresX
Typically MSSX
MSI due to MLH1 gene promoter methylationX
CINX
CIMP-lowX
CIMP-highX
Microsatellite and chromosome stable CRCX
Hypomethylation of LINE 1X
Table 2 Clinical and molecular features associated with hereditary colorectal cancer syndromes
Hereditary CRC syndromeAge of presentationGene(s)Clinical features
Lynch syndromeAverage age of diagnosis of CRC is 42-45 yrMLH1, MSH2Lifetime risk of CRC 70%
MSH6,PMS2,EPCAMRisk of extracolonic cancers
Classic FAPAverage age of diagnosis of CRC is 39 yrAPC100-1000 adenomas
MUTYH (biallelic)CRC risk 90% without colectomy
Risk of extracolonic cancers
Attenuated FAPAverage age of diagnosis of CRC is 51 yrAPC, MUTYH mutations detected in approximately 10%10-99 adenomas
PJSPolyps occur during childhood and early adulthoodSTK11Mucocutaneous pigmentation
≥ 2 hamartomatous polyps in small bowel
Lifetime cancer risks 80%-90%
JPSLate childhood or early adolescenceSMAD4, BMPR1A, ENG> 3-5 juvenile polyps in the gastrointestinal tract
Congenital cardiac valvular disease and/or atrial and ventricular septal defects
PPAPSecond through fourth decades of lifePOLEOligo adenomatous polyposis
POLD1Young-onset CRC
Endometrial cancer
Cowden diseaseSecond and third decades of lifePTENVariable CRC risk
Macrocephaly
Increased risk of thyroid, breast, and endometrial cancer