Lynch Syndrome in India: A Silent Hereditary Cancer Risk That Every Family Should Know About

For Gujarat-based families with multiple relatives affected by colorectal or related cancers, this discovery is particularly relevant.

What Does This Mean for Patients?

1. Early Detection Can Save Lives

Many people develop cancer before realizing they carry an inherited risk.

If Lynch Syndrome is identified early:

• Colonoscopies can begin earlier.
• Precancerous polyps can be removed.
• Cancers can be detected at an earlier, more curable stage.

The study highlights that many affected individuals remain undiagnosed and therefore miss opportunities for surveillance and prevention.

2. One Test Can Protect an Entire Family

Lynch Syndrome is inherited in an autosomal dominant manner.

This means:

• Each child of an affected parent has approximately a 50% chance of inheriting the mutation.
• Siblings and other close relatives may also be at risk.

Once a mutation is identified in one patient, family members can undergo targeted testing and preventive screening.

3. Better Treatment Decisions

MSI-H and MMR-deficient tumors often respond differently to modern immunotherapy drugs.

The study notes that increasing MSI testing has become clinically important because MSI-H/MMRd cancers may benefit from tissue-agnostic immunotherapy approaches. s10689-026-00607-7 (2)

This means genetic and molecular testing may directly influence treatment choices.

What Does This Mean for Families?

Families should consider genetic counseling if they have:

Multiple relatives with:

• Colon cancer
• Uterine cancer
• Ovarian cancer
• Stomach cancer

Or if cancer occurred:

• Before age 50
• In multiple generations
• In the same individual more than once

The study found that family history remained a powerful clue for identifying Lynch Syndrome.

What Does This Mean for Doctors?

This study carries several important messages for clinicians across India.

Universal Tumor Testing Should Become Routine

The authors support broader implementation of:

• MSI testing
• MMR immunohistochemistry
• Germline confirmation testing
• Cascade testing for relatives

to improve cancer prevention and surveillance. s10689-026-00607-7 (2)

Think Beyond Colorectal Cancer

While colorectal cancer had the highest yield, Lynch Syndrome was also identified in:

• Endometrial cancers
• Ovarian cancers
• Other extracolonic tumors

Doctors should maintain a high index of suspicion even when patients present with non-colorectal malignancies.

Family History Still Matters

Although molecular testing is essential, careful family history remains a highly valuable screening tool.

Patients with:

• Multiple affected relatives
• Early-onset cancers
• Lynch-associated tumors

should be prioritized for genetic evaluation. s10689-026-00607-7 (2)

The Future of Cancer Prevention in India

The study strongly supports a “Tumor-First” approach, where newly diagnosed cancer patients undergo MSI/MMRd testing followed by genetic confirmation when appropriate. This strategy helps identify not only the patient at risk but also family members who may benefit from surveillance and preventive care.

As genetic testing becomes more accessible across India, identifying Lynch Syndrome early could prevent many cancers before they become life-threatening.

Take-Home Message

Lynch Syndrome is not rare. It is underdiagnosed.

This landmark Indian study demonstrates that:

• Nearly one in four tumors showed MSI/MMRd changes.
• More than half of these patients had confirmed Lynch Syndrome.
• A potentially important Gujarat founder mutation has been identified.
• Family-based screening can save lives across generations.

For patients and families, the message is simple:

Knowing your family history and seeking appropriate genetic evaluation may be one of the most powerful tools for preventing cancer.

Author: Team Dwarika Gastro & Weight Loss Superspeciality Hospital, Ahmedabad
Clinical Review: Dr. Avinash Tank, MS, MCh (SGPGIMS)
Robotic Liver & Gastro Surgeon