Getting a second opinion on a cancer diagnosis is very common, and most doctors welcome it, says the US National Cancer Institute.

That is how the US National Cancer Institute puts it. A second opinion is another specialist’s view of the diagnosis and the treatment plan, usually before treatment begins. This guide sets out when one makes sense, what to bring, what the research shows and what rights patients have in Germany, the United Kingdom, the United States and Switzerland. It gives no treatment advice: decisions about treatment stay with you and your treating doctors.

When a second opinion makes sense

The National Cancer Institute describes a second opinion as another doctor’s opinion before you begin treatment; the second doctor may agree with the first or suggest changes. The American Cancer Society, in guidance reviewed by the American Society of Clinical Oncology, lists situations in which one is worth considering: a rare or unusual cancer, uncertainty about the type or stage of the cancer, a doctor who is not a specialist in that cancer, several treatment options, or an insurer that asks for one.

Germany’s Cancer Information Service at the German Cancer Research Center says a second opinion may be an option if questions or uncertainty remain, and adds that two different medical recommendations do not automatically mean that one of them is wrong. The health department of Basel-Stadt in Switzerland considers a second opinion especially useful before non-urgent surgery or a treatment with far-reaching consequences.

Is there time to wait?

Usually there is, according to two cancer organizations. The American Cancer Society says that usually you can take some time to think about treatment decisions, although for a few cancers some decisions might need to be made right away. The German Cancer Information Service states that cancer treatment is, as a rule, not an emergency.

But a second opinion takes time to arrange, and Cancer Research UK advises asking whether a delay could be harmful. NHS Wales notes that a second opinion may delay treatment, which patients with serious conditions should weigh. We found no reliable published figure for how long a cancer second opinion takes; it depends on the specialty and on how complete the records are. The question to put to your treating doctor is therefore simple: how long can this safely wait?

What to bring

A second opinion is only as good as the file it is based on. The American Cancer Society lists the documents to have ready, starting with the pathology report from any biopsy or surgery:

  • the pathology report from any biopsy or surgery
  • the operative report, if you had surgery
  • the hospital discharge summary
  • a summary of the current treatment plan
  • a list of all medicines you take, with doses

Imaging and test results belong in the file as well. The NCI advises involving your treating doctor, who will need to make your records, such as test results and x-rays, available. In Germany, the Federal Joint Committee’s patient leaflet asks patients to bring all relevant findings already obtained, so that tests are not repeated, and states that handing them over costs the patient nothing; by law, the statutory insurer pays the doctor’s costs of compiling them for that procedure.

What pathology reviews found

The figures vary widely because the studies measure different things, from slide reviews at large cancer centers to second opinions sought by patients. They cannot be combined into one percentage.

At the Mayo Clinic, a review of 71,811 cases referred from other institutions found 457 major disagreements, or 0.6 percent. Where follow-up was available, the changed diagnosis affected treatment in 126 of 140 cases, or 90.0 percent. Mandatory second opinion pathology at Johns Hopkins changed 86 of 6,171 diagnoses, or 1.4 percent, in ways with a major impact on therapy or prognosis.

Two breast pathology reviews, measuring other outcomes, reported higher rates. At Mount Sinai, review changed the diagnosis in 72 of 430 specimens, or 17 percent, and surgical management in 41, or 10 percent. At MD Anderson, a second review found discrepancies that affected patient care in 226 of 1,970 breast cases, or 11.47 percent.

What reviews of second opinions found

A systematic review by authors from the German Cancer Society, covering 13 studies, found that second opinions led to changes in diagnosis, treatment or prognosis in 12 to 69 percent of cases, while the original diagnosis or treatment was confirmed in 43 to 82 percent. Depending on the study, between 6.5 and 36 percent of cancer patients sought a second opinion. A 2021 review across all medical specialties found that second opinions which differed from the first had a potential major impact on patient outcomes in up to 58 percent of cases.

The American Cancer Society adds that studies show the benefits of a second opinion are unclear. In each of the pathology reviews above, most diagnoses held, and in the Mayo Clinic review a changed diagnosis affected the treatment in nine in ten followed-up cases.

Your rights in Germany

Germany has a statutory rule. Under section 27b of the Social Code Book V, people with statutory health insurance have a legal right to an independent second opinion for planned procedures designated by the Federal Joint Committee (G-BA), from a doctor or institution that would not carry out the procedure. The G-BA’s list currently names 13 procedures, and it is to add at least two each year. Since 1 April 2025, it has included procedures for localized prostate cancer without metastases: removal of the prostate, external radiotherapy or interstitial brachytherapy.

The doctor who recommends such a procedure must normally inform the patient of this right at least ten working days in advance, and taking it up is voluntary. Authorized second opinion doctors are listed at 116117.de/zweitmeinung. For further procedures, many statutory insurers offer a second opinion as an extra benefit, with a scope that varies by insurer.

Your rights in the UK, the US and Switzerland

United Kingdom

Cancer Research UK states that there is no legal right to a second opinion, although professional guidance says doctors must respect a patient’s right to seek one, and NHS Wales notes that a referral is rarely refused. For a second consultant’s opinion, patients go back to their GP and ask to be referred again; a private second opinion is the other route.

United States

The NCI says many health insurers pay for a second opinion or even require one, particularly before surgery, and the American Cancer Society notes that some plans pay for treatment only after a second opinion from a doctor in their network. Medicare Part B covers a second opinion before medically necessary surgery that is not an emergency; you pay 20 percent of the Medicare-approved amount after the deductible, and Medicare also covers a third opinion if the first two differ. New York State requires comprehensive health insurance contracts to cover a second medical opinion for a cancer diagnosis; rules differ from state to state.

Switzerland

Cantonal health authorities state that patients have the right to consult another health professional of their choice, and advise checking in advance whether the health insurer will pay for the second opinion.

Where Veltracon Medical stands

Veltracon Medical arranges second opinions; it does not give them. Through the Global Second Opinion Network, part of the Holistic and Longevity memberships, members have access to specialist doctors affiliated with leading medical institutions such as Harvard and Yale University, who review the case and confirm or revise the diagnosis. Our coordinators help assemble the reports, images and laboratory results from the treating doctors and hospitals, place the case with a specialist in the relevant field and go through the result with you. The specialist gives the opinion independently, and the decision remains yours and your treating doctor’s.

There is no fixed turnaround; it depends on the specialty and on how complete the records are. If treatment follows, we arrange it in Switzerland through concierge medicine, with the clinics our sister company Switzerland Clinics presents, or abroad through our network. Further examinations and treatment are charged by the provider. Our page on the medical second opinion describes how a review runs, and our guide explains what a medical concierge does. Contact us to discuss a case.

About this article

This guide quotes cancer organizations, health authorities, statutes and peer-reviewed studies; all sources were accessed in November 2026. The study figures come from different settings and are reported separately on purpose. It is general information, not medical advice, and it does not recommend any treatment.

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