When Is Informed Consent Needed?

The informed consent process should begin before you start cancer treatment. If you are getting more than one treatment, you will probably need to sign separate informed consent forms. For example, if you are having surgery to remove cancer and then will have chemotherapy or radiation to treat it, you will need to give consent for both surgery and either the chemotherapy or radiation.

Some medical procedures that may require you to give written informed consent include:

  • Radiation
  • Chemotherapy (including targeted therapy and immunotherapy)
  • Surgery
  • Some complex or advanced medical tests and procedures, such as a biopsy (removing cells from a suspicious area so that they can be looked at in the lab to see if cancer cells are present)
  • Some vaccines
  • Some blood tests or other tests or procedures

Parts of informed consent are regulated by state and case law. In general, those who make medical decisions must be recognized as adults in the state where the treatment is to be given. For children or others who are unable to make the decision for themselves, a parent or legal guardian is legally responsible for getting the information, making the decision, and signing the consent form. Some facilities require mentally competent older children who are being treated to give assent (willingness to participate) before they go into a research study, even after the parents have agreed on the child’s behalf. Assent means that, even though the parents sign the form, the child must also be okay with the plan before the facility will do the treatment.

There are times when the usual informed consent rules do not apply. This varies from state to state and may include:

  • In an emergency, if a person is unconscious and in danger of death or other serious outcomes if medical care is not given right away, informed consent may not be required before treatment.
  • If those who are giving treatment know that the patient has an advance directive that states the patient refuses the care, the treatment may not be given.
  • When a decision made by the parent or guardian of a child or an incompetent adult may be challenged by the doctor or facility, the courts may evaluate the situation.
  • An older teen (for example, one who is self-supporting and doesn't live at home, is married, pregnant, or in the military) does not need parental consent for treatments or procedures.

A patient may wish to delegate his/her right to make informed decisions to another person. (See Advance Directives for more detailed information on this process.) This choice should be madeto the extent permitted by the law. Sometimes, the patient may be unconscious or unable to make an informed decision. In these cases, the hospital must check their records for the patient's advance directives , medical power of attorney or the patient's representative. As soon as the patient is able to be informed of his/her rights, the health care provider must give the patient that information.

Another option is a court-appointed surrogate or proxy. This is someone a judge chooses to make decisions for you if you become unable to make decisions for yourself. Some states have passed family agency acts that choose which family members (listed in order of priority) may act on behalf of a patient if the patient doesn't have an advance directive or medical power of attorney.

The American Cancer Society medical and editorial content team

Our team is made up of doctors and oncology certified nurses with deep knowledge of cancer care as well as journalists, editors, and translators with extensive experience in medical writing.

Centers for Medicare & Medicaid Services (CMS). Revisions to the hospital interpretive guidelines for informed consent. 2007. Accessed at https://www.cms.gov/Medicare/Provider-Enrollment-and-Certification/SurveyCertificationGenInfo/downloads/SCLetter07-17.pdf on February 19, 2019.

Katz AL, Webb SA, Committee on Bioethics. Informed consent in decision-making in pediatric practice. AAP News & Journals; 2016;138(2):e1-e13.

MedlinePlus. Informed consent-adults. 2017.Accessed at https://medlineplus.gov/ency/patientinstructions/000445.htm on February 19, 2019.

Moye J, Sabatino CP, Brendel RW. Evaluation of the capacity to appoint a health care proxy. American Journal of Geriatric Psychiatry; 2013;21(4):326-336.

Storm C, Casillas J, Grunwald H, Howard DS, McNiff K, Neuss MM.  Informed consent for chemotherapy: ASCO member resources. Journal of Oncology Practice; 2016;6:289-295.

Last Medical Review: May 10, 2019 Last Revised: May 10, 2019

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