Importance of Receiving Treatment as Scheduled

Reviewed by Bronwyn Long, DNP, MBA, RN, Jeffrey Kern, MD, Laurie L. Carr, MD

What happens if you miss a dose of chemotherapy or a radiation treatment? Cancer treatment is designed to kill as many cancer cells as possible. If you miss treatments, the cancer cell killing does not happen. The cancer cells have an opportunity to continue to grow. They may become more resistant to treatment.

Chemotherapy and radiation therapy have a number of side effects. If treatments are missed, you may experience treatment side effects without as many cancer cell killing effects.


It is important to receive the prescribed dose of chemotherapy at the scheduled time. This will give you the best chance to benefit from treatment. Chemotherapy treatment follows a specific schedule. This schedule was determined after many years of research to learn the best dose and timing of treatment. Chemotherapy is given in a number of cycles that together add up to one whole treatment.

The treatment plan you have been given by your team is most likely to give you the best result. Not following this plan reduces the chances it will work as well.

Sometimes changes to your chemotherapy schedule are unavoidable.

Treatment Delays

Low white blood cell count. One of the reasons your blood work is checked just before treatment is to look at your blood counts. If your white blood cell count is too low, your cancer doctor may delay treatment. This is done for your safety. Receiving chemotherapy would lower your white count even more. White blood cells fight infections. Giving you chemotherapy while your white blood cell count is low could increase your risk for infection.

Infection. If you have a fever or are feeling sick, your chemotherapy may be delayed until you feel better. This is done for your safety, so you can recover from the infection.

Dose Reduction

Toxicity. If your dose of chemotherapy causes side effects severe enough to delay treatment, your cancer doctor may lower your dose of chemotherapy. This may make it safer for you. If you are too sick or weak to receive chemotherapy, your treatment will be delayed.

Radiation Therapy

Radiation therapy works best when you receive it without interruption. Typically, radiation therapy is given every weekday. Radiation is designed to be done in a string of treatments or “fractions.” Each fraction adds up to a whole number of radiation given. Similar to chemotherapy, reducing the overall dose of radiation therapy can mean your cancer treatment may not be as successful.

Dose Reduction

If your dose of radiation causes side effects severe enough to delay treatment, your radiation doctor may lower your dose of radiation. This is done to make it safer for you to tolerate. If you are too sick or weak to receive radiation, your treatment will be delayed.


If you become sick while receiving treatment and need to visit an ER, try to visit the ER of the hospital where you are receiving treatment. If you are admitted to the hospital, you may be able to continue receiving radiation treatment as an inpatient.

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