Colorectal Cancer Stage II

Stage II colorectal cancer has spread into the outer layers of the colon or rectum but has not yet reached the lymph nodes or other organs, making it one of the better prognosis cancers when treated appropriately.

Table of contents

• What is Stage II Colorectal Cancer?
• How Stage II is Divided
• Treatment Options
• Making Treatment Decisions

What is Stage II Colorectal Cancer?

In stage II colorectal cancer, the cancer has spread into the outer layers of the colon or rectum but has not spread to any lymph nodes (small bean-shaped structures that are part of the body’s immune system)^[1]. The cancer has also not spread to other organs or distant parts of the body^[6].

Stage II colorectal cancer is probably one of the best prognosis gastrointestinal tumors. An estimated 75% of people with stage II colon cancer will be cancer-free 5 years later, even without additional chemotherapy after surgery^[4][11].

How Stage II is Divided

Stage II colon cancer is divided into three categories based on how deeply the cancer has grown into the colon or rectum wall^[1].

Stage IIA

Cancer has spread into the muscularis propria layer of the colon (a thick outer muscle layer) but has not grown beyond it. It has not spread to any other organs or lymph nodes^[1][6].

Stage IIB

Cancer has spread through to the outermost layer of the colon wall, which is called the serosa (the membrane that covers and supports the colon and rectum). It has not spread to any other organs or lymph nodes^[1][6].

Stage IIC

Cancer has spread through the colon wall and into nearby tissue. It has not spread to any other organs or lymph nodes^[1][6].

Treatment Options

Surgery

Surgery is the main treatment for stage II colon cancer. Often the only treatment that is needed is a partial colectomy, a surgery that removes the section of colon where the cancer is located^[1].

Surgery usually involves a bowel resection (removal of the affected part of the bowel) with a lymph node dissection (removal of nearby lymph nodes for examination). The type of bowel resection depends on the location of the tumor^[13].

A colostomy or ileostomy may be done after the bowel resection, depending on the location of the cancer and how healthy the remaining colon is after surgery. A colostomy creates an opening from the colon to the outside of the body through the abdominal wall, while an ileostomy creates an opening from the ileum (part of the small intestine). These procedures create a new path for stool to leave the body. The colostomy or ileostomy can be temporary to allow the intestine to rest and heal after surgery^[13].

Chemotherapy

Chemotherapy may be offered after surgery if there is a high risk that the cancer will come back. The decision to use chemotherapy for stage II colon cancer is an area of ongoing discussion among doctors^[11].

Chemotherapy after surgery, called adjuvant chemotherapy, aims to destroy any microscopic cancer cells that may remain and reduce the risk of the cancer returning^[14]. However, since many people with stage II colon cancer are cured by surgery alone, doctors must carefully consider which patients are most likely to benefit from chemotherapy^[11].

Chemotherapy may be considered if at least one of the following high-risk features is present^[13]:

• The tumor is T4 (stage IIB or IIC)
• Fewer than 12 lymph nodes were removed or could be assessed
• The tumor has grown into nearby lymph nodes, blood vessels, or the space surrounding nerves
• The tumor is high grade (poorly differentiated)
• There is a blockage in the intestine (bowel obstruction) or a tear or hole in the intestine (bowel perforation)
• Not enough healthy tissue was removed along with the tumor, or cancer cells are found in the tissue removed with the tumor

The chemotherapy drugs that may be given for stage II colon cancer include^[13]:

• Capecitabine (Xeloda)
• 5-fluorouracil (Adrucil, 5-FU) with leucovorin (folinic acid)
• Oxaliplatin (Eloxatin)
• FOLFOX – leucovorin, 5-fluorouracil and oxaliplatin
• CAPOX (also called XELOX) – capecitabine and oxaliplatin

Making Treatment Decisions

Making treatment decisions for stage II colon cancer can be complex. Stage II colon cancer is a diverse disease, and patients fall into different groups. Some are cured by surgery alone and the cancer will not return regardless of additional treatments. Others have microscopic disease that may return regardless of treatment. A third group has microscopic disease that can be eliminated by chemotherapy, leading to a cure^[11].

The first step in treatment decision making is to assess the patient’s overall health and any other medical conditions to see if the patient is eligible for additional treatment after surgery. Then, depending on the patient’s characteristics and tumor risk stage, the strategy may be observation alone, chemotherapy with a single drug, or chemotherapy with a combination of drugs^[4].

Risk classification through looking at specific features of the tumor is important to help doctors determine the appropriate treatment. Features such as having fewer than 12 lymph nodes examined and T4 tumors (stage IIB and IIC) are currently recognized as major factors associated with worse outcomes^[4].

Because chemotherapy has side effects, doctors want to avoid unnecessarily exposing people to treatment unless they are confident it will help. The benefit of chemotherapy for many people with stage II colon cancer is small at best, and it comes with the risks of real and sometimes serious complications^[11].