NCCN Guidelines for Patients
Rectal Cancer, Version 1.2017
A cancer stage is a rating by your doctors of the
extent of the cancer. It is used to plan which tests
may be needed and which treatments are best
for you. The AJCC (
ancer) staging system is used to stage rectal
In the AJCC system, the letters T, N, and M describe
the areas of cancer growth. The T score describes
the growth of the primary tumor. It also describes
the level of invasion into nearby tissue. The N score
describes nearby cancer growth within nearby lymph
nodes. The M score tells if the cancer has spread to
The T, N, and M scores are combined to assign
the cancer a stage. There are five stages of rectal
cancer. They are numbered 0, I (1), II (2), III (3), or IV
(4). The stages are defined as:
These cancers are also called carcinoma in situ of
the rectum. The cancer has not grown beyond the
first layer of the rectal wall. It is a noninvasive cancer.
More treatment may not be needed if all the cancer
was removed during an endoscopic polypectomy.
The cancer has grown into either the second or third
layer of the rectal wall. There is no cancer in nearby
or distant sites.
The cancer has grown outside the rectal wall. It
may have attached or grown into other structures or
organs. There is no cancer in nearby or distant sites.
The cancer has spread from the rectum to nearby
lymph nodes or there are tumor deposits. Nearby
nodes include the presacral, perirectal, and internal
iliac nodes. Tumor deposits are small secondary
tumors within the rectal wall.
The rectal cancer has spread to distant organs.
Common distant sites include your liver and lungs.
Clinical vs. pathologic stage
Rating of the cancer stage is often done twice. The
first rating is based on tests before treatment. It is
called the clinical stage. Tests include a physical
exam and imaging described in Part 2.
The pathologic stage is a rating done after surgery.
The pathologic stage may be the same or differ from
the clinical stage. Sometimes the full extent of the
cancer isn’t known until after surgery.
The rectum stores stool until it is expelled from
Layers of tissue make up the rectal wall.
Rectal cancer is a cancer of cells that line the
inner rectal wall and make mucus.
Cancer cells form a tumor since they don’t grow
and die as normal cells do.
Cancer cells sometimes spread from the rectum
to other sites through lymph or blood.
Most rectal cancers start in polyps.
The cancer stage is a rating by doctors of the
extent of cancer.
Rectal cancer basics