Rectal cancer is usually treated with a combination of surgery, chemotherapy, and radiation, chosen based on the cancer's stage and exactly where it sits in the rectum. Early cancers may need surgery alone. More advanced cancers often get chemotherapy and radiation first, and some people whose tumor fully disappears may be able to avoid major surgery with very close monitoring.

How is rectal cancer different from colon cancer?

The rectum sits low in the pelvis, close to the sphincter muscles that control the bowels, so treatment is planned differently than for colon cancer.

The rectum is the last several inches of the large intestine. Because it is in a tight space near the bladder, sexual organs, and sphincter muscles, radiation is used more often, and surgery has to be very precise. A big goal of rectal cancer care is to treat the cancer fully while protecting bowel control and quality of life whenever possible.

What tests are done before rectal cancer treatment starts?

Staging tests show how deep the tumor goes and whether it has spread, and they guide every treatment decision.

• Colonoscopy with biopsy to confirm the cancer and check the rest of the colon
• Pelvic MRI to see how deep the tumor grows and how close it is to nearby structures
• CT scan of the chest, abdomen, and pelvis to look for spread
• CEA blood test, a tumor marker that can be followed over time
• Tumor testing for features such as mismatch repair status, which can change which treatments work best

Results are often reviewed by a team that includes a colorectal surgeon, medical oncologist, radiation oncologist, radiologist, and pathologist. This team approach is a key part of current rectal cancer guidelines.

What are the main treatment options for rectal cancer?

The main options are surgery, chemotherapy, radiation therapy, and, for some tumors, immunotherapy or targeted therapy.

According to the National Cancer Institute, two or more of these are often combined, either at the same time or one after another. The order depends on the stage and location of the cancer.

What is total neoadjuvant therapy (TNT)?

Total neoadjuvant therapy means giving all of the planned chemotherapy and radiation before surgery, instead of splitting chemotherapy before and after the operation.

For many people with locally advanced rectal cancer (stage II or III), TNT has become a common approach. It allows patients to complete their full chemotherapy plan and lets the care team see how well the tumor responds. The ASCRS 2023 guideline update addresses TNT as part of modern rectal cancer care.

Is surgery always needed for rectal cancer?

Not always. Some very early cancers can be removed through the anus, and some people whose tumor disappears after treatment may choose close monitoring instead of major surgery.

• Local excision: Select small, early tumors can be removed through the anus without any cuts on the belly. Dr. Belizaire performs transanal excision, including robotic transanal minimally invasive surgery (TAMIS), when it is safe to do so.
• Watch and wait: If chemotherapy and radiation make the tumor disappear on exams, scopes, and MRI (called a clinical complete response), ASCRS guidelines say a watch-and-wait approach may be considered in carefully selected patients. In the OPRA trial, up to about half of patients treated with TNT kept their rectum long term. Most regrowth happened in the first 2 years, which is why watch-and-wait requires frequent exams, scopes, and MRI scans for years. This follow-up is usually led by your oncology team.
• Immunotherapy: For tumors with a feature called mismatch repair deficiency, immunotherapy is increasingly used, and in some cases it may be the first treatment.

What does rectal cancer surgery involve?

The standard operation is called total mesorectal excision (TME). It removes the part of the rectum with the cancer, along with the surrounding fatty tissue and lymph nodes.

There are two main types of TME surgery:

• Low anterior resection: The cancer is removed and the colon is reconnected to the remaining rectum or anus. This keeps the sphincter muscles and allows normal passage of stool.
• Abdominoperineal resection: When the cancer grows into or very close to the sphincter muscles, the rectum and anus are removed together, and a permanent colostomy is created.

Many rectal cancer operations can be done with minimally invasive or robotic surgery. Compared with open surgery, robotic surgery uses smaller incisions and often means less pain and a shorter hospital stay, with similar complication rates. Dr. Belizaire performs robotic rectal cancer surgery and works closely with oncology teams across Houston. Learn more about robotic colon and rectal surgery in Houston.

Will I need an ostomy after rectal cancer surgery?

Most people who have a low anterior resection do not need a permanent ostomy, but a temporary one is common.

When the new connection is low in the pelvis, the surgeon often creates a temporary ileostomy. This lets stool leave the body through an opening on the belly while the connection heals. The temporary ileostomy is usually reversed in a smaller operation, often about 2 to 3 months later or after chemotherapy is finished. You can read more about ostomy surgery and reversal.

What is recovery like after rectal cancer surgery?

Most people return to light activity in about 2 to 6 weeks and feel fully recovered in about 6 to 12 weeks. Recovery after rectal surgery can be a bit longer, especially after radiation.

After a low anterior resection, bowel habits often change. Some people have more frequent bowel movements, urgency, or clusters of stools. This is sometimes called low anterior resection syndrome. These changes often improve over the first year or two, and diet changes, fiber, medicines, and pelvic floor therapy can help. Regular follow-up visits, scans, and colonoscopies are part of care for years after treatment.

Why does an experienced team matter for rectal cancer?

Rectal cancer care works best when specialists plan together and the surgeon has focused training in pelvic surgery.

Board-certified colorectal surgeons complete extra training in operating on the colon, rectum, and anus. Dr. Ritha Belizaire is a double board-certified general and colorectal surgeon who operates at many hospitals across Houston, so patients can often get care close to home. If you have just been diagnosed, it is reasonable to ask questions about every option, including whether your sphincter can be preserved and whether watch-and-wait might apply to you.

Frequently Asked Questions

Can rectal cancer be cured?

Many rectal cancers can be cured, especially when found early. Outcomes depend on the stage and how the cancer responds to treatment, and no treatment can guarantee a result.

How long does rectal cancer treatment take?

Treatment often takes several months from start to finish, especially when chemotherapy and radiation are given before surgery. Follow-up continues for several years.

What symptoms should I get checked?

Rectal bleeding, a change in bowel habits, thinner stools, a feeling that you have not fully emptied, unexplained weight loss, or low blood counts should be evaluated. Do not assume bleeding is just hemorrhoids.

Will I lose bowel control after surgery?

Bowel changes are common after low rectal surgery, but they often improve over time, and there are treatments that can help.

When should my family members start screening?

Adults at average risk should begin colorectal cancer screening at age 45. Close relatives of someone with colorectal cancer may need to start earlier. Learn more about colon cancer screening in Houston.

Request a consultation

A rectal cancer diagnosis brings many questions, and you deserve clear answers. You can request a consultation with Dr. Belizaire at houstoncommunitysurgical.com to review your options.

Sources

• You YN, et al. The American Society of Colon and Rectal Surgeons Clinical Practice Guidelines for the Management of Rectal Cancer. Dis Colon Rectum. 2020.
• Langenfeld SJ, et al. The American Society of Colon and Rectal Surgeons Clinical Practice Guidelines for the Management of Rectal Cancer 2023 Supplement. Dis Colon Rectum. 2024.
• Long-Term Results of Organ Preservation in Patients With Rectal Adenocarcinoma Treated With Total Neoadjuvant Therapy: The Randomized Phase II OPRA Trial. J Clin Oncol.
• National Cancer Institute. Rectal Cancer Treatment (PDQ) – Patient Version.
• American Cancer Society. Rectal Cancer Surgery.
• American Cancer Society. Rectal Cancer Treatment, by Stage.
• U.S. Preventive Services Task Force. Colorectal Cancer: Screening.