Written and medically reviewed by: Assoc. Prof. Cengiz Dibekoğlu, MD, General SurgeryLast updated:
Hereditary Cancers — Lynch Syndrome
MMR/MSI, colorectal risk, and family screening
Lynch syndrome is linked to germline mismatch-repair gene mutations and raises colorectal and endometrial cancer risk. The path often starts with tumor MMR/MSI findings, then genetic counseling and confirmatory germline testing.
Educational schematic. Some structures may be simplified or emphasized for clarity; not an exact anatomical depiction.
© Cengiz Dibekoğlu — illustrative; not for unauthorized use
Figure summary
This educational figure shows: Lynch.
Key points
Why MMR/MSI is checked
Universal MMR/MSI assessment in new colorectal cancers informs immunotherapy discussions, prognosis framing, and Lynch evaluation — it is not reserved only for young patients.
- Key note inside
Surgery and follow-up
Resection extent and surveillance intensity depend on confirmed risk, anatomy, and patient goals. There is no single package for every Lynch patient.
Family cascade
Pathogenic germline findings trigger relative testing and screening conversations under genetic counseling.
- Key note inside
Important
This page is for education. It is not medical advice and does not replace a visit with your physician.
Frequently asked questions
Does MSI-high equal Lynch?
Not by itself. It raises the question and guides next steps with counseling.
Is total colectomy mandatory?
No. Extent of colorectal surgery is individualized.
More chapters in this hub
Hereditary Cancer Overview
When hereditary risk is considered and how sequencing works
BRCA and Familial Breast Risk
Who is offered testing; surgery and surveillance frame
FAP
Polyposis, APC, and surgical timing
MUTYH and Serrated Polyposis
MAP, serrated pathway, and surveillance intervals
CDH1
Hereditary diffuse gastric cancer risk
Li-Fraumeni Syndrome
TP53 and multi-cancer spectrum
Peutz–Jeghers Syndrome
Hamartomatous polyps and surveillance
Genetic Counseling
Consent, results, and talking with relatives
Molecular Testing in Cancer
Organ-specific biomarkers that often open this conversation
Appointment / info
This page is for education. It is not medical advice and does not replace a visit with your physician.
Medical editor: Assoc. Prof. Cengiz Dibekoğlu, MD · Last medically reviewed: August 2026 · English patient-education chapter.