Bowel Problems and Quality of Life After Colon Cancer Surgery: What Patients Should Know

Table of Contents

• Key Points
• Background: Why This Research Matters
• Study Methods: How the Research Was Conducted
• Key Findings: What the Researchers Discovered
• Risk Factors for Bowel Complaints After Colon Surgery
• Impact on Quality of Life
• Why Do These Symptoms Occur?
• Clinical Implications: What This Means for Patients
• Study Limitations
• Recommendations for Patients
• Frequently Asked Questions
• Source Information

Key Points

• In a study of 1,495 patients, 20.9% of colon cancer survivors had major LARS-like bowel symptoms.
• Major LARS symptoms lowered quality-of-life scores as much in colon cancer patients as in rectal cancer patients.
• Women and patients with a previous temporary stoma were about twice as likely to develop major symptoms.
• Doctors should discuss bowel risks before colon surgery and monitor survivors afterward, since symptoms can persist for years.

Background: Why This Research Matters

Survivors of colorectal cancer often face long-term side effects that can last for years after their treatment ends. These include troublesome abdominal complaints, depressive symptoms, and fatigue. For many patients, these persistent issues significantly affect their physical and social functioning — the everyday activities that define quality of life.

In patients treated for rectal cancer (cancer of the lower part of the large intestine), these postoperative bowel complaints are well-documented and are collectively known as low anterior resection syndrome (LARS). Studies have shown LARS affects 60–90% of rectal cancer patients.

However, very little research has focused on whether patients who undergo surgery for colon cancer (cancer in the upper parts of the large intestine) experience similar problems.

Previous research had hinted at the issue. One recent cross-sectional study showed that patients treated for sigmoid tumours (the S-shaped section of the colon just before the rectum) experience post-treatment symptoms even years after the event. Another study found that patients who had a right hemicolectomy (removal of the right side of the colon) experience persistent diarrhoea in the first 3 months after surgery, leading to a decreased quality of life.

What has been lacking is a large, systematic study looking at the full range of bowel symptoms after colon cancer surgery and their impact on how patients live their lives. The authors of this study also noted that colorectal surgeons often do not have a thorough understanding of the problems patients face after colonic surgery.

This study set out to answer a simple but important question: How common are functional bowel complaints after colon cancer surgery, and how do they affect quality of life compared with what we already know about rectal cancer patients?

Study Methods: How the Research Was Conducted

The researchers carried out a multicentre, retrospective cross-sectional study in the south-east of the Netherlands. They invited all patients who had undergone surgery for Stage 1–3 colorectal cancer between January 2008 and December 2015 at six hospitals to participate. Patients who had a temporary colostomy or ileostomy could participate if their stoma had been closed for more than a year, to allow bowel function to stabilise.

The six participating hospitals were:

• VieCuri Medical Centre, Venlo
• Laurentius Hospital, Roermond
• Zuyderland Hospital, Sittard and Heerlen
• Maxima Medical Centre, Veldhoven
• Maastricht University Medical Centre
• Catharina Hospital, Eindhoven

Patients were excluded if they had died, were under 18 years old, had disseminated or recurrent disease, had inadequate Dutch language skills, or had intellectual disability or dementia. Patients with irresectable disease or locally excised tumours (such as those removed by transanal endoscopic microsurgery) were also excluded.

Questionnaires Used

Patients received a letter with information about the study, an informed consent form, and three questionnaires. They could complete them at home and return them free of charge. Non-responders received a reminder after 8 weeks.

The researchers used three validated tools to measure bowel function and quality of life:

The LARS Score. This internationally validated tool measures bowel dysfunction after rectal cancer surgery. It consists of five questions with a total score ranging from 0 to 42 points. Patients are classified into three categories:

• No LARS: 0–20 points
• Minor LARS: 21–29 points
• Major LARS: 30–42 points

The EORTC QLQ-C30. This questionnaire consists of 30 questions measuring functional scales (physical, role, emotional, cognitive, and social functioning), global quality of life, and symptoms (such as fatigue, pain, and diarrhoea). A high functional score means better function; a high symptom score means more symptoms.

The EORTC QLQ-CR29. This questionnaire is specifically designed for colorectal cancer patients. It includes 29 items addressing gastrointestinal symptoms, side effects of chemotherapy, defaecation problems, pain, problems with urination, and separate items on sexual function for men and women.

What Data Were Collected

The researchers also gathered clinical data from electronic patient files, including:

• Gender and age
• Marital status
• Body mass index (BMI)
• American Society of Anesthesiologists (ASA) score (a measure of overall health and surgical risk)
• Complications (classified using the Clavien–Dindo scale)
• Tumour stage and location
• Treatment received and time since surgery

Key Findings: What the Researchers Discovered

Who Was Included

A total of 5,824 patients were operated on for colorectal cancer between January 2008 and December 2015. Of these, 2,136 were eligible for the study and received an invitation letter. The reasons for exclusion were:

• Death (n = 850)
• Metastatic disease (n = 1,288)
• Stage 4 tumours (n = 218)
• Presence of a colostomy or ileostomy (n = 897)
• Local excision (n = 120)
• Relapse of disease (n = 192)
• Mental disability (n = 84)
• Missing address (n = 11)
• Poor Dutch language proficiency (n = 28)

Of the 2,136 patients invited, 82.6% completed and returned the questionnaires, while 12.6% returned an unfilled questionnaire with reasons for declining. This left 1,495 patients for analysis: 1,145 with colon cancer and 350 with rectal cancer.

Differences Between Colon and Rectal Cancer Patients

Almost all baseline characteristics differed significantly between the two groups. Rectal cancer patients were younger (median age 71 versus 73 years, P < 0.001), had more early-stage (Stage 0–1) tumours (44.9% versus 27.6%, P < 0.001), and had fewer comorbidities (ASA Grade I: 29.2% versus 24.0%, P < 0.001). Time since surgery was longer for rectal patients (median 5 versus 4 years, P < 0.001), and they were much more likely to have had a temporary diverting stoma (78.9% versus 11.1%, P < 0.001) and neoadjuvant therapy (radiotherapy before surgery: 72% versus 1.7%, P < 0.001).

More rectal cancer patients underwent open surgery (55.3% versus 43.0%, P < 0.001), and the types of anastomosis (the surgical connection joining the remaining bowel) differed significantly between groups. There was no significant difference in the use of adjuvant chemotherapy (P = 0.207).

Prevalence of LARS Symptoms

The headline finding: Major LARS was observed in 20.9% (n = 237) of patients after colon cancer surgery, compared with 55.4% (n = 194) of patients after rectal cancer surgery. This means more than 1 in 5 colon cancer survivors had symptoms severe enough to be classified as "major LARS."

Minor LARS was distributed more evenly between the groups:

• Colon cancer patients: 19.5% (n = 221) experienced minor LARS
• Rectal cancer patients: 20.7% (n = 73) experienced minor LARS

When the researchers broke down the results by the specific type of surgery performed, the percentage of patients reporting major LARS was:

• Rectal resection: 51.2%
• Sigmoid resection: 20.4%
• Left hemicolectomy: 14.3%
• Right hemicolectomy: 22.3%

This is a striking finding. Sigmoid resection (removing part of the lower colon) was associated with as many major LARS symptoms as right hemicolectomy (removing part of the upper colon), and both were significantly more common than after left hemicolectomy.

Risk Factors for Bowel Complaints After Colon Surgery

The researchers performed both univariate (single-factor) and multivariate (multiple-factor) analyses to identify which patients were most likely to develop major LARS-like symptoms after colon cancer surgery.

In the initial univariate analysis, colon cancer patients with major LARS were more likely to:

• Be female (P < 0.001)
• Have had a previous temporary stoma (P = 0.012)
• Have had mild postsurgical complications according to the Clavien–Dindo scale (P = 0.037)

Interestingly, patients with a tumour in the transverse colon, splenic flexure, or descending colon (P = 0.061) and patients who received adjuvant chemotherapy (P = 0.010) reported fewer major LARS symptoms.

In the multivariate analysis, four factors stood out as independent predictors:

1. Female gender: Women were nearly twice as likely as men to suffer from major LARS symptoms (OR = 1.88, CI 1.392–2.528, P < 0.001).
2. Previous diverting stoma: Patients who had a temporary stoma in the past were also nearly twice as likely to develop major LARS symptoms (OR = 1.84, CI 1.14–2.97, P = 0.012).
3. Left hemicolectomy: Patients who underwent a left hemicolectomy (removal of the left side of the colon) were less likely to suffer from major LARS symptoms (OR = 0.55, CI 0.31–0.97, P = 0.040).
4. Adjuvant chemotherapy: Patients who received chemotherapy after surgery were also less likely to suffer from major LARS symptoms (OR = 0.64, CI 0.45–0.89, P = 0.010).

For patients, this means women and those who needed a temporary stoma during their treatment journey should be especially aware that bowel symptoms may persist — and should raise these concerns with their medical team.

Impact on Quality of Life

The study clearly demonstrated that major LARS symptoms significantly damage quality of life. On average, patients with major LARS symptoms reported a poorer global quality of life score of 70.9 (SD 19.4) compared with 80.8 (SD 17.1) for patients with no or minor LARS symptoms.

The difference in quality of life between the no/minor LARS and major LARS groups was most dramatic in specific surgical groups:

• After (sub)total colectomy (removal of all or most of the colon): a difference of −26.8 points in mean QoL score
• After right hemicolectomy: a difference of −13.3 points

General Quality of Life Measures (EORTC QLQ-C30)

In multivariate analysis adjusting for other factors, colon cancer patients with major LARS symptoms reported:

• Lower emotional functioning (OR 0.98, CI 0.98–0.99, P = 0.006)
• More pain (OR 1.01, CI 1.00–1.02, P = 0.034)
• More insomnia (OR 1.006, CI 1.00–1.01, P = 0.047)
• More diarrhoea (OR 1.04, CI 1.03–1.05, P < 0.001) — the strongest association of all general symptoms

Colorectal-Specific Quality of Life (EORTC QLQ-CR29)

On the colorectal-specific questionnaire, patients with major LARS symptoms reported:

• Less anxiety about the future (OR 1.016, CI 1.01–1.02, P < 0.001)
• Higher stool frequency (OR 1.05, CI 1.04–1.06, P < 0.001)
• More incontinence (OR 1.03, CI 1.02–1.04, P < 0.001)
• More problems controlling flatulence (OR 1.02, CI 1.01–1.03, P < 0.001)

Perhaps the most important finding for patients is this: There was no significant difference in quality of life between colon and rectal cancer patients with major LARS symptoms (P = 0.138). In other words, a colon cancer patient with major bowel complaints suffers just as much as a rectal cancer patient with major LARS.

Why Do These Symptoms Occur?

The researchers discussed several possible explanations for why colon cancer surgery can lead to LARS-like symptoms. The underlying causes are likely multifactorial (involving multiple mechanisms at once).

Loss of water and electrolyte absorption. The colon's primary job is to absorb water and electrolytes from digested food. When part of the colon is removed, there is less absorptive capacity remaining. This predisposes patients to more liquid stool, increased bowel frequency, excess gas, and a higher risk of faecal incontinence.

Reduced reservoir function. The rectum acts as a storage chamber for stool before defecation. In a sigmoid resection, the rectum may be incorporated into the anastomosis (the surgical connection), which can reduce its reservoir function. This explains why sigmoid resection patients had a prevalence of major LARS symptoms (20.4%) close to that of right hemicolectomy patients (22.3%). In contrast, because the anastomosis in a left-sided colonic resection is colo-colonic (colon connected to colon), the reservoir function of the rectum is spared, and functional complaints are less likely — which was indeed observed (14.3%).

Differences between right and left resections. Previous studies have shown significantly more abdominal complaints after right-sided than left-sided colonic resections, consistent with the differing absorptive functions of different colon segments.

Clinical Implications: What This Means for Patients

This study is the first to raise awareness that LARS-like symptoms occur after surgery for colon cancer, not just after rectal cancer surgery. The authors were explicit that the effect on quality of life is just as severe.

Several practical implications follow for patients and clinicians:

Pre-surgical counselling. Colorectal cancer specialists should inform patients facing colon cancer surgery that they may experience long-term bowel dysfunction, including urgency, frequent bowel movements, gas, and incontinence. Until now, these risks have typically been discussed mainly with rectal cancer patients.

Post-surgical monitoring. Doctors should actively ask colon cancer survivors about bowel function during follow-up visits. Patients may not volunteer this information out of embarrassment, or may assume it is a normal consequence of surgery that cannot be improved.

Treatment options. Patients with major LARS-like symptoms after colon surgery deserve the same attention and treatment options as rectal cancer patients with LARS. These may include dietary adjustments, medications to slow bowel transit or bind stool, pelvic floor physiotherapy, and in severe cases, interventions such as sacral nerve stimulation. The study did not evaluate these treatments, but it highlights the need for them.

The surprising chemotherapy finding. One puzzling result was that patients who received adjuvant chemotherapy (post-operative chemotherapy) reported fewer major LARS symptoms. The authors noted this finding but did not have a clear physiological explanation. It is possible that patients receiving chemotherapy had more intense follow-up and nutritional support, or the finding may be due to selection bias — for example, patients with more aggressive tumours may have had different types of surgery. Patients should not interpret this as a reason to seek chemotherapy; it is simply an association observed in this study.

Study Limitations

As with all research, this study has limitations that patients should understand when interpreting the results.

Retrospective and cross-sectional design. The study looked back at patients at one point in time rather than following them forward. This means the researchers cannot establish cause and effect — they can only show associations. For example, the finding that chemotherapy was associated with fewer LARS symptoms could be due to unmeasured factors rather than the chemotherapy itself.

Self-reported symptoms. All bowel symptoms and quality-of-life data were self-reported through questionnaires. Patients' recollection and reporting can vary, and there is no objective measurement of bowel function.

Selection bias. Although the response rate was high (82.6%), the 12.6% of patients who returned unfilled questionnaires may have differed systematically from those who participated. It is possible that patients with more severe symptoms were either more or less likely to respond.

No baseline data. The researchers did not have pre-surgery bowel function data, so they cannot determine how much of the reported bowel dysfunction was caused by the cancer surgery versus pre-existing bowel habits or age-related changes.

Not population-wide. Patients with permanent stomas, metastatic disease, and recurrent disease were excluded. This means the prevalence figures may not apply to the entire colon cancer survivor population. Also, all hospitals were in one region of the Netherlands, so results may not generalise to other countries with different surgical practices.

Recommendations for Patients

Based on this study, here is practical advice for patients facing or recovering from colon cancer surgery:

1. Ask about bowel function before surgery. When discussing surgery with your surgeon, ask specifically: "What bowel symptoms might I have after this operation, and how long might they last?" This study shows that troublesome symptoms can persist for years — not just the first few months.
2. Report symptoms after surgery. Do not dismiss ongoing bowel problems as something you have to live with. Bring them up at follow-up appointments. The study shows bowel complaints are common and that effective discussion can lead to better management.
3. Know your risk. The study found women and patients who had a temporary stoma during treatment are at higher risk of developing major LARS-like symptoms after colon surgery. If this applies to you, be especially proactive in seeking help.
4. Understand that symptoms vary by surgery type. Major bowel symptoms were seen in 14.3% of patients after left hemicolectomy, 20.4% after sigmoid resection, and 22.3% after right hemicolectomy. Even the "lowest risk" group still had a meaningful chance of troublesome symptoms.
5. Quality of life matters. If bowel symptoms are interfering with your daily activities, sleep, or emotional wellbeing, know that this is not trivial — the study shows a substantial drop in quality of life. There is no shame in asking for help. Treatments exist, even if they were not the focus of this study.
6. Consider what you eat. While this study did not test dietary interventions, the mechanism it describes (reduced water absorption in the remaining colon) suggests that dietary adjustments to manage stool consistency may be beneficial. Discuss this with your doctor or a dietitian specialising in colorectal surgery recovery.

Frequently Asked Questions

What are LARS-like symptoms after colon cancer surgery?

LARS-like symptoms include urgency, frequent bowel movements, excess gas, and faecal incontinence. In a Dutch study of 1,495 patients, more than one in five colon cancer survivors had major symptoms that significantly damaged their quality of life. These problems can persist for years after surgery, not just the first few months.

How common are bowel problems after colon cancer surgery?

In a study of 1,495 colorectal cancer patients, 20.9% of colon cancer patients had major LARS symptoms and 19.5% had minor symptoms. So roughly two in five colon cancer survivors experienced some degree of LARS-like bowel dysfunction. Rectal cancer patients had major LARS in 55.4% of cases, but colon cancer patients were still frequently affected.

Who is at higher risk for major bowel symptoms after colon cancer surgery?

Women were nearly twice as likely as men to have major LARS symptoms, and patients who previously had a temporary stoma were also nearly twice as likely. Patients who had a left hemicolectomy or adjuvant chemotherapy reported fewer major symptoms. If you are female or had a stoma, be especially aware and discuss symptoms with your team.

Should I discuss bowel risks before colon cancer surgery?

Yes. The study's authors advise that surgeons should inform patients about the possibility of long-term bowel dysfunction, including urgency, frequent stools, gas, and incontinence. Until now, these risks were mainly discussed with rectal cancer patients. Before surgery, ask your surgeon what bowel symptoms you might have and how long they might last.

What treatments are available for LARS-like symptoms after colon surgery?

The study did not evaluate treatments, but it says patients with major LARS-like symptoms deserve the same attention and options as rectal cancer patients. These may include dietary adjustments, medications to slow bowel transit or bind stool, pelvic floor physiotherapy, and in severe cases, sacral nerve stimulation. Discuss these options with your healthcare team.

Why does colon cancer surgery cause bowel symptoms?

Removing part of the colon reduces its ability to absorb water and electrolytes, leading to looser stool, more frequent bowel movements, gas, and incontinence. In sigmoid resection, the rectum's reservoir function may also be reduced. Left hemicolectomy spares the rectum, which likely explains why that group had fewer major symptoms.

Source Information

Original article title: Functional bowel complaints and quality of life after surgery for colon cancer

Authors: M. van Heinsbergen, N. den Haan, A. J. Maaskant-Braat, J. Melenhorst, E. H. Belgers, J. W. Leijtens, J. G. Bloemen, H. J. Rutten, N. D. Bouvy, M. L. Janssen-Heijnen, and J. L. Konsten

Journal: Colorectal Disease, 22(2), 136–145

Publication date: February 1, 2020 (accepted July 9, 2019; published online August 9, 2019)

DOI: 10.1111/codi.14818

Institutions: Department of Surgery, VieCuri Medical Centre, Venlo; Maxima Medical Centre, Veldhoven; Maastricht University Medical Centre+; Zuyderland Medical Centre, Heerlen; Laurentius Medical Centre, Roermond; Catharina Hospital, Eindhoven; and GROW School for Oncology and Developmental Biology, Maastricht University, The Netherlands.

This patient-friendly article is based on peer-reviewed research. It does not provide individual medical advice. Patients should consult their healthcare team about their specific situation.