Low anterior resection syndrome (LARS) describes a collection of bowel dysfunction symptoms that can occur after a surgical procedure called low anterior resection (LAR). LARS is not a single condition but rather a set of challenges related to bowel function that arise as a consequence of anatomical and physiological changes.
What is Low Anterior Resection Syndrome
Low anterior resection (LAR) is a surgical procedure performed to remove a portion of the rectum, often to treat rectal cancer. The rectum, located at the end of the large intestine, stores stool before it is passed. During an LAR, the cancerous section of the rectum and surrounding healthy tissue are removed. The remaining colon is then reconnected to the remaining part of the rectum or directly to the anus; this reconnection is known as an anastomosis. The goal of this surgery is to remove the tumor while preserving the anal sphincter, often avoiding a permanent colostomy.
LARS symptoms result from several changes to normal bowel anatomy and function. The removal of part of the rectum reduces its capacity to store stool. This often leads to bowel movements becoming smaller and more frequent.
The surgical procedure can also damage nerves controlling bowel function, including those supplying the internal anal sphincter. This can impair signals that regulate bowel movements and the ability to differentiate between gas and stool. The rectococcygeus muscle, which contributes to rectal function, may also be divided during surgery, further affecting bowel control. Radiation therapy, often given for rectal cancer, can also contribute to LARS by scarring rectal walls and affecting nerve function.
Recognizing the Symptoms
LARS presents with a diverse range of symptoms. One common symptom is increased bowel frequency, where individuals need to have bowel movements many times a day. This is often accompanied by urgency, a sudden and strong need to defecate with little warning.
Fecal incontinence, involving the unintentional leakage of stool or gas, is another frequently reported symptom. Some individuals experience “clustering,” meaning they have multiple bowel movements within a short period, often over a few hours. A feeling of incomplete evacuation, where one feels that not all stool has been passed even after a bowel movement, is also common.
Patients may also find it difficult to distinguish between gas and stool, leading to unexpected leakage. Other symptoms include unpredictable bowel habits, where frequency and consistency of stool are irregular. Sometimes constipation is followed by periods of frequent, loose stools. Bowel pain or discomfort can also occur, and some patients report painful defecation.
Managing Low Anterior Resection Syndrome
Managing Low Anterior Resection Syndrome often begins with conservative approaches aimed at controlling symptoms. Dietary modifications are a common first step. This may involve adjusting fiber intake, avoiding trigger foods like caffeine, alcohol, spicy foods, or fatty foods, and ensuring adequate hydration by sipping fluids slowly. Eating smaller, more frequent meals (e.g., 5-6 per day) can also be helpful. Some individuals find that soluble fiber supplements, such as psyllium-based products, improve stool consistency by absorbing water, which can help slow and thicken stool.
Lifestyle adjustments also play a role in managing LARS. Establishing regular bowel habits and practicing good toileting posture can encourage more complete bowel emptying. Pelvic floor exercises, which strengthen the muscles controlling bowel function, can help improve urgency and stool incontinence. Over-the-counter medications like loperamide are frequently used to control diarrhea and reduce stool frequency by slowing bowel movements and firming up stool consistency. Probiotics may also be considered, though their effect on LARS symptoms is not consistently demonstrated.
For individuals with more severe or persistent LARS symptoms, advanced therapies may be considered. Biofeedback therapy can help retrain the bowel and strengthen pelvic floor muscles and sphincters to improve bowel control. Sacral neuromodulation involves stimulating nerves that supply the rectum and anus to enhance bowel control. Transanal irrigation, which involves introducing water into the rectum to stimulate a bowel movement, can be an effective method for managing symptoms, particularly for those with emptying difficulties or severe incontinence. In rare and severe cases where other treatments have not provided sufficient relief, a stoma (ostomy) may be considered as a last resort to divert stool and improve quality of life.
Living with Low Anterior Resection Syndrome
Living with Low Anterior Resection Syndrome can significantly impact a person’s quality of life, affecting physical, emotional, and social well-being. The unpredictable nature of bowel function can lead to preoccupation with bowel habits, feelings of dissatisfaction, and dependence on toilet access. This may limit social activities and return to work. Patients may also experience changes in intimacy and concerns about fecal leakage during social situations.
Despite these challenges, various coping strategies can help individuals navigate life with LARS. Seeking support groups can provide a valuable space for sharing experiences and learning from others facing similar issues. Open communication with healthcare providers is important to discuss symptoms and adjust management strategies as needed. Carrying a “survival pack” with items like wet wipes and protective ointments can offer practical support for managing unexpected bowel movements.
While LARS can be persistent, symptoms improve over time, usually within months to a few years, as the body adapts to the changes. Although some individuals may experience chronic symptoms, effective management strategies are available to improve quality of life. Maintaining a positive outlook and focusing on available interventions can empower individuals to manage their condition and lead fulfilling lives.