Understanding Breast Cancer Diagnosis: What to Expect and Why Second Opinions Mattera

Early detection and accurate diagnosis are critical in breast cancer care. This article walks you through the steps doctors take to confirm a diagnosis, from imaging tests to biopsies, and explains why seeking a second opinion can help you make informed decisions about your treatment and understand what your breast cancer treatment timeline might look like.

How is breast cancer diagnosed?

Whether you notice concerning breast changes yourself, or a doctor sees something concerning in a routine screening or appointment, a breast cancer diagnosis will begin with a doctor’s exam to look for any signs and symptoms of breast cancer. Should your doctor discover a lump or a mammogram detect an area of abnormal breast tissue, your doctor may recommend additional tests like an ultrasound or magnetic resonance imaging (MRI).

Ultrasound can confirm whether the lump is a solid tumor or a fluid-filled, noncancerous cyst. It can also be used to assess any abnormal areas found on a mammogram.

Although it is not routinely performed, MRI may be used to assess abnormalities on a mammogram, get a more accurate estimate of a cancer's size, and check for other cancers.

If the lump is solid, your doctor probably will recommend a breast biopsy. During a biopsy, a small amount of breast tissue is removed and analyzed in a laboratory.

A breast biopsy can be done in different ways. These include:

• fine-needle aspiration, which uses a thin needle to withdraw tissue from the tumor
• large-core needle biopsy, which allows larger pieces of tissue to be removed
• stereotactic needle biopsy, a type of large core needle biopsy that uses special imaging equipment to pinpoint the tissue to be removed
• surgical biopsy, which involves removing all or part of the breast lump.

The type of biopsy your doctor chooses will depend on the location of the lump, its size, and other factors.

A specialist called a pathologist will examine the tissue under a microscope to determine whether the tissue contains cancer cells. If it does, the pathologist can determine the type of breast cancer.

When to seek a second opinion

When you're facing a life-altering diagnosis like cancer, it's often worth it to seek out a second opinion. Even if you trust your diagnosing doctor, getting a second opinion will help you and your family make better-informed choices about your care — even if the second opinion is exactly the same as the first.

Benefits of seeking a second opinion

Even though it may feel overwhelming to go through the process of talking through your diagnosis yet again, the benefits usually far outweigh the negatives. For example, you'll likely look for someone who is a specialist in your type of cancer. By talking to a specialist in, say, breast cancer, you may gain access to information about new research or treatment options that didn't come up in your original appointment.

You may also have an opportunity to talk to a larger team of specialists, such as pathologists, radiologists, or surgeons, all of whom can give you and your family more information about your cancer and your treatment options.

Finally, you may find that you understand your cancer better simply by talking to a new medical team about it. In some cases, you may have a better connection to a second-opinion doctor and might consider transferring your care to that medical facility.

What to know before you seek a second opinion

• Don't procrastinate. The best time to seek a second opinion is before you begin treatment, as it could impact your treatment plan.
• Be honest with your original doctor. It might seem awkward to bring up, but your doctor won't be angry or offended if you tell them you want to talk to someone else. Doctors generally welcome having their patients seek second opinions and may even encourage another expert's thoughts on your case — or have suggestions for someone specific you should talk to. You'll also need to coordinate with your original doctor to obtain your health records and pathology results.
• Call your health insurance first. Second opinions sometimes lead to less expensive tests and treatments, so insurers have good reason to allow — and even encourage — you getting a second opinion. Still, it's worth calling your insurance provider before you set up an appointment, just to be sure the appointment is covered.

How to get a second opinion

There are several ways to gather more medical advice. You might start with your primary care doctor to get some guidance on how to proceed. He or she may refer you to someone with more experience treating your type of cancer. But if you want another expert opinion after consulting with an oncologist, ask him or her for a recommendation. And remember, just because you went for a second opinion elsewhere doesn't mean you've burned a bridge with your original oncologist. After getting a second opinion, you should feel free to go back to your first doctor to discuss what you've learned and explore the reasons for any differences in recommended next steps.

What happens if the second opinion is the same?

Usually, the doctor reviewing your case has special expertise in the suspected problem. With a complicated illness like cancer, a number of specialists (pathologists, radiologists) might be called on to offer a second opinion. Sometimes a third, tie-breaking opinion is helpful in resolving conflicting advice, but going beyond that and getting too many opinions could cause harmful delays.

A second opinion might confirm a first diagnosis or treatment recommendation, but that doesn't mean it was a waste. If the two opinions agree, you can feel confident knowing that both medical teams are aligned on your diagnosis and proposed treatment. Also, a second opinion can be helpful just because another doctor may explain things in a way that's easier for you to understand.

Your health deserves clarity and confidence. If you or a loved one is facing a breast cancer diagnosis, remember that knowledge and expert advice are powerful tools. Don’t hesitate to ask questions, seek second opinions, and explore all your options.

This article is part of our collaboration with Harvard Health Publishing, a trusted source of medical expertise from Harvard Medical School. Content has been adapted for local audiences.

Copyright © 2025 by Harvard University. Original work prepared by Harvard Health Publishing. This content is for informational purposes only and does not replace professional medical advice, and do not represent the views of Manulife (Singapore) Pte. Ltd.