Get a Second Opinion

The importance of a second opinion

Cancer is a serious disease, and you should feel confident in your diagnosis and comfortable with your treatment plan. If you have doubts about either, talking to another doctor can help give you peace of mind.

What is a second opinion?
The U.S. National Cancer Institute defines it as the opinion of a doctor other than the patient’s current doctor. The opinion of the second doctor may confirm or question the first doctor’s diagnosis and treatment plan. The second doctor may also give more information about the patient’s disease and offer other treatment options.¹

Here are some of the reasons why you might want to seriously think about getting a second opinion – even if you’ve already started treatment.

• If your cancer was detected during routine screening.
• If you have been diagnosed with a rare type of cancer.
• When test results are unclear or inconclusive.
• When your test results are unclear for the type and location of your cancer.
• If you are not comfortable with your diagnosis or treatment plan..
• To validate your diagnosis and current treatment approach.
• If you want to be sure you have explored all options.
• If your cancer is advanced or aggressive.
• If you have a family history of cancer mortality.
• When considering different treatment options.
• If you’re given several treatment options but feel unsure what to do.
• If you received very different recommendations for treating your cancer.
• If treatment is not working as expected.
• If your doctor does not have a lot of experience treating your type of cancer.
• If your cancer doctor is not a specialist in the type of cancer you have.
• If you’re having trouble understanding and communicating with your doctor.
• To broaden your options (e.g., one surgeon says that a tumor is not operable, but another surgeon at a high-volume center who treats that cancer regularly may have the experience and expertise to perform the surgery).

Most doctors do not object to or take offense at a request for a second-opinion referral. They view it as a normal part of patient care and informed decision-making.

“Health care professionals make hundreds of decisions a day. A small fraction of them are based on evidence from rigorous clinical trials — that is, things we really know to be true. Unfortunately, most medical decisions are based on clinical opinion — an educated guess.”

Jeffrey M. Drazen, Editor in chief of the New England Journal of Medicine from 2000 to 2019.

1. National Cancer Institute. Definition of cancer. NCI Dictionary of Cancer Terms. Accessed July 27, 2026. https://www.cancer.gov/publications/dictionaries/cancer-terms/def/second-opinion

Before starting cancer treatment

Last updated January 2026