How Long is Chemotherapy Given?
The length of chemotherapy treatment is determined by a variety of factors.
These include the type of cancer, the extent of cancer, the types of drugs that
are given, as well as the expected toxicities of the drugs and the amount of time
necessary to recover from these toxicities. Many chemotherapy treatment schedules
(including the type and length of chemotherapy treatment) have been determined
through clinical trials that compared them and determined which had the most benefit
and was most well tolerated.
In general, chemotherapy treatment is given in cycles. This allows the
cancer cells to be attacked at their most vulnerable times, and allows the body's
normal cells time to recover from the damage. There are really three issues
regarding the cycle time, duration of the cycle, frequency of the cycle, and how
Duration of the cycle: Chemotherapy treatment may be
a single drug or a combination of drugs. The drugs may all be given on a single
day, several consecutive days, or continuously as an outpatient or as an inpatient.
Treatment could last minutes, hours, or days, depending on the specific protocol.
Frequency of the cycle: Chemotherapy may repeat weekly, bi-weekly,
or monthly. Usually, a cycle is defined in monthly intervals. For example,
two bi-weekly chemotherapy sessions may be classified as one cycle.
The number of cycles: In most cases, the number of cycles
- or the length of chemotherapy from start to finish - has been determined
by research and clinical trials.
- When cure is the treatment goal. Adjuvant chemotherapy (therapy after surgery
has removed all visible cancer) may last 4-6 months. Adjuvant chemotherapy
is common in cancers of the breast and colon. In cancers of the testis, Hodgkin
and non-Hodgkin lymphoma, and leukemias, length of chemotherapy treatment may be
up to a year.
- When there is visible disease, the length of chemotherapy treatment will depend
upon the response of the disease to therapy. If the disease disappears completely,
chemotherapy may continue for 1-2 cycles beyond this observation to maximize the
chance of having attacked all microscopic disease.
- If the disease shrinks but does not disappear, chemotherapy will continue as
long as it is tolerated and the disease does not grow.
- If the disease grows, the chemotherapy will be stopped. Depending on the health
and wishes of the patient, either different drugs will be given to try to kill the
cancer, or chemotherapy will be stopped and the goal changed to focus on patient
More Chemotherapy Information:
Protocols - How Chemotherapy Works
How Chemotherapy Is Given
How Doctors Decide Which Chemotherapy Drugs To Give
How Long Chemotherapy Is Given
How To Tell If Chemotherapy Is Working
Cancer Cells & Chemotherapy
Short & Long Term Side Effects of Chemotherapy
Cancer Clinical Trials