NCCN Guidelines for Patients
Rectal Cancer, Version 1.2017
Overview of cancer treatments
Ablation destroys small tumors with little harm to
nearby tissue. It is done by either an interventional
radiologist or a surgeon. It isn’t used often for rectal
Doctors sometimes consider ablation for metastases.
Most often it is considered for rectal cancer that has
spread to the liver or lung. Ablation is only an option
if all the first sites of cancer can be treated with this
method, with or without surgery or radiation.
There is more than one way to “ablate” a tumor.
Cryoablation kills cancer cells by freezing them with
liquid nitrogen. Radiofrequency and microwave
ablation kills cancer cells with high-energy radio
waves. A probe placed into the tumor emits the
waves. The probe is guided into place with help from
an imaging test and is removed when treatment is
Embolization treats liver tumors with chemotherapy
or radioactive beads. It is done by an interventional
radiologist. He or she often teams up with a surgeon
or radiation oncologist.
A catheter will be inserted into an artery in your leg. It
will then be guided to the blood vessels that feed the
tumor. Once in place, the beads will be inserted into
the blood vessels.
The beads block blood flow to the tumor. Without
blood, the cancer cells “starve” and die. The
chemotherapy or radiation further damage the cancer
cells and cause the tumor to shrink.
This treatment is a type of arterially directed
catheter therapy. If radiation beads are used, it’s
called selective internal radiation therapy or Y-90.
Embolization is an option for some people with liver
One of your treatment choices may be to join
a clinical trial. Joining a clinical trial is strongly
supported. NCCN believes that you will receive the
best management in a clinical trial.
New tests and treatments aren’t offered to the
public as soon as they’re made. They first need to
be studied. A clinical trial is a type of research that
studies a test or treatment in people.
Clinical trials study how safe and helpful tests and
treatments are for people. When found to be safe
and helpful, they may become tomorrow’s standard
treatment. Because of clinical trials, the tests and
treatments in this book are now widely used to
help people with rectal cancer. Future tests and
treatments that may have better results than today’s
treatments will depend on clinical trials.
New tests and treatments go through a series of
clinical trials. These trials aim to ensure they’re safe
and work. Without clinical trials, there is no way to
know if a test or treatment is safe or helpful. Clinical
trials have four phases. Some examples of the four
phases for treatment are:
Phase I trials
aim to find the safest and best
dose of a new drug. Another aim is to find the
best way to give the drug with the fewest side
effects. These trials often involve about 20
Phase II trials
assess if a drug works for
a specific type of cancer. These trials often
involve 20 to 100 people.