. 2017 May 16;296(1):123–127. doi: 10.1007/s00404-017-4392-y

Table 2.

Revised Bethesda guidelines

Tumors from individuals should be tested for MSI in the following situations

1. Colorectal cancer diagnosed in a patient who is less than 50 years of age
2. Presence of synchronous, metachronous colorectal or other HNPCC-associated tumors^a, regardless of age
3. Colorectal cancer with the MSI-high histology^b diagnosed in a patient who is younger than 60 years of age
4. Colorectal cancer diagnosed in one or more first-degree relatives with an HNPCC-related tumor^a, with one of the cancers being diagnosed before age 50 years
5. Colorectal cancer diagnosed in two or more first- or second-degree relatives with HNPCC-related tumors, regardless of age

Umar et al. [9]

^aHNPCC-related tumors include colorectal, endometrial, gastric, ovarian, pancreatic, ureter/renal pelvis, biliary tract and brain (usually glioblastoma as seen in Turcot syndrome) tumors, sebaceous gland adenomas and keratoacanthomas in Muir–Torre syndrome, and carcinoma of the small bowel

^bPresence of tumor infiltrating lymphocytes, Crohn’s-like lymphocytic reaction, mucinous/signet-ring differentiation or medullary growth pattern