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POLE/POLD1 mutations testing: what it means for you

Waiting on test results can feel like one more hard thing, for you and the people who love you. Here's what the POLE/POLD1 mutations test looks for and how it can help your care team pick the treatment most likely to work for you.

ℹ️ General information to help you and your loved ones talk with your care team, not medical advice. Read our disclaimer.

Matters most in: Colorectal cancer

Why it matters

These tumors often look like MSI-high cancers to the immune system, even when MSI and mismatch repair tests are normal. That's why a POLE/POLD1 change can point to immunotherapy for some people with advanced colorectal cancer.

Treatments it can point to

• Immunotherapy (checkpoint inhibitors) such as Keytruda (pembrolizumab) or Opdivo (nivolumab) may be considered for advanced POLE/POLD1-mutated tumors (Keytruda (pembrolizumab), Opdivo (nivolumab))

Only your care team can say which treatment fits you. Drug approvals depend on cancer type, stage and prior treatment.

Tissue vs. blood testing

Tumor tissue, on a broad gene panel (often reported along with tumor mutational burden).

Most tests use a piece of tumor tissue from a biopsy or surgery. Some can also use a blood sample (a 'liquid biopsy') that looks for tumor DNA floating in the blood. Blood tests are easier and faster, but they can miss a change that a tissue test would find, so a negative blood test is often followed by a tissue test.

❓ Questions you and your loved ones can ask

• Did my gene panel check POLE and POLD1?
• Could immunotherapy help me even though my MSI test was normal?
• When will my results be back, and will treatment wait for them?
• Will my insurance cover this test?

Written by the Cancer Side Effects Guide team from FDA labels and leading cancer centers. Not medical advice. · Last updated: October 15, 2026 · How we write