Lower Anterior Resection Syndrome (LARS)

Lower Anterior Resection Syndrome (LARS) is a group of symptoms that can happen after colorectal cancer surgery. If you have had surgery to remove all or part of your rectum, including low anterior resection (LAR) surgery and total mesorectal excision (TME) surgery, you may be at risk of LARS. The goal of colorectal surgery is to preserve your anal sphincter and avoid a permanent colostomy. About 30 to 40 out of 100 people who have these surgeries will develop some degree of LARS.

LARS can happen when the muscles and nerves near your rectum are damaged during surgery. These muscles and nerves help control when you feel like you need to have a bowel movement (poop) and can also change your ability to have normal bowel movements. Surgery for colorectal cancer may also lessen space in your rectum for poop to be held before you have a bowel movement. This can also cause LARS.

LARS isn’t life-threatening, but it can affect your quality of life, your ability to be part of social activities, relationships/sexual intimacy, how you feel about your body, and your self-image.

Symptoms of LARS

Symptoms of LARS can be:

• More gas (farting) or having trouble telling the difference between gas and a bowel movement.
• Feeling like you need to have a bowel movement urgently or unexpectedly.
• More frequent bowel movements.
• Bowel incontinence (you cannot control your bowel movement).
• Feeling like you haven’t finished a bowel movement (like you still need to poop but can’t).

Who is at risk for LARS?

If you have had surgery for colorectal cancer, you could develop LARS. However, some may be more at risk.  Your risk of LARS is increased by:

• Your tumor size and location, especially the height of the tumor and how close it was to your anus.
• The type of surgery you had for your cancer
• Your own anatomy.
• If you had a temporary stoma (colostomy) after surgery.
• If you had radiation before or after surgery.
• If you had combined chemo-radiation and surgery.
• Complications you may have had after surgery.
• Younger age.
• If you had problems with moving your bowels or incontinence before surgery.

How is LARS diagnosed?

After surgery, your provider may use a screening tool called the LARS score to check how your bowels are working and how bad any bowel problems you have had since surgery have been. This will help your provider understand more about how your bowels are working after surgery and can help with treatment planning.

How is LARS treated?

Your treatment plan will depend on how badly LARS is affecting your bowel movements and habits. Treatment can include many different things, including:

• Diet changes: A high-fiber diet can help you have solid bowel movements. It can also decrease the feelings of needing to go and leaking. A dietitian can help you understand how food affects your bowel movements and can guide you on what to eat while meeting your nutrition needs.
• Medication: Medications like loperamide, ramosetron, lamosetron, atropine, and raceanisodamine may help with LARS. These medications can interact with chemotherapy. Be sure to talk to your provider before starting any medications to help with your bowel movements.
• Physical Therapy: Pelvic floor muscle training and rectal balloon training can help build up your muscle strength and your ability to control your rectal muscles. Your provider can refer you to a physical therapist who specializes in pelvic floor rehabilitation.
• Enemas (Transanal irrigation): Enemas wash out the colon, which can delay the need to have a bowel movement. Talk to your provider about if and how often you can use an enema to help with your symptoms and about any risks.
• Surgery:
  • Sacral nerve stimulation (SNS) is when a small device is used to send mild electrical pulses to the sacral nerves in your lower back. It changes the signals between your body and your brain. This can help control muscles in your pelvic floor and around your anus, so that it stays closed until you are ready to have a bowel movement.
  • Colostomy: If these treatment options don’t work to help your LARS, you may need a permanent colostomy. It is important to think about how your symptoms are affecting your quality of life and to talk with your surgeon about your options.
• Counseling and support groups: Connecting with others who are having LARS can help you feel less alone and learn about ways to cope. If your LARS is impacting your sexual relationships, you may want to ask your provider for a referral for a sex-focused therapist who can work with you and your partner. Therapists can also help you with ways to manage social situations and to prepare yourself for symptoms so you can continue to work, socialize, and do other things you enjoy.

Talking to Your Provider

After surgery, it's important to follow up regularly with your provider and report any bowel symptoms you're having. Keeping a journal of your symptoms and bowel movements can help guide your care. LARS can be a challenging side effect of colorectal cancer surgery, but with the right combination of treatments, you can see improvement in your symptoms and quality of life.