From the Guidelines
When asking about symptoms of colorectal cancer, focus on changes in bowel habits, rectal bleeding, iron deficiency anemia, and other signs that may indicate the presence of the disease, as early detection significantly improves treatment outcomes. The most recent and highest quality study, 1, recommends prompt evaluation with colonoscopy or at least with flexible sigmoidoscopy for individuals under 50 years old presenting with signs and symptoms of colorectal cancer (CRC) such as iron deficiency anemia, rectal bleeding, or change in bowel habits.
Key Symptoms to Inquire About
- Changes in bowel habits, such as persistent diarrhea, constipation, or narrowing of stools lasting more than a few days
- Rectal bleeding or blood in the stool (bright red or very dark)
- Persistent abdominal discomfort, including cramps, gas, or pain
- Feeling that the bowel doesn't empty completely
- Unexplained weakness or fatigue
- Unintended weight loss These symptoms are important to identify because colorectal cancer often develops slowly from precancerous polyps, and early detection significantly improves treatment outcomes, as noted in 1 and 1. Many early-stage colorectal cancers produce no symptoms, which is why regular screening is crucial for those over 45 or with family history. The symptoms mentioned can also be caused by other conditions like hemorrhoids, inflammatory bowel disease, or infections, but persistent symptoms warrant medical evaluation to rule out cancer. When discussing these symptoms with a healthcare provider, be specific about duration, severity, and any patterns you've noticed to help with accurate diagnosis.
From the Research
Symptoms of Colorectal Cancer
To identify symptoms of colorectal cancer, the following should be considered:
- Rectal bleeding, which has a specificity of 99.4% and a positive predictive value (PPV) of 4.0% 2
- Faecal occult blood in stool (FOBT) or anaemia, which may indicate gastrointestinal bleeding 2
- Abdominal pain, lower part, constipation, and distended abdomen, bloating, although these symptoms are less specific and less sensitive than rectal bleeding 2
- Persistent symptoms, which may revise the PPV upwards and justify a specific referral 2
Factors to Consider
When asking about symptoms of colorectal cancer, it is essential to consider the following factors:
- Location of the cancer, as proximal and distal colon cancers may present with different symptoms 2
- Stage and grade of the cancer, as these can impact the presentation of symptoms 3
- Individual patient characteristics, such as age, lifestyle, and genetic biomarkers, which can influence the risk of colorectal cancer and its symptoms 4, 3
Diagnostic Approaches
The following diagnostic approaches may be used to identify colorectal cancer:
- Surgical procedures, such as laparoscopic and robotic surgery 5
- Radiotherapy, chemotherapy, and immunotherapy, which may be used in combination with surgery 6
- Targeted therapy and multitherapies, which are being investigated as potential treatment options 6, 3
- Screening programs, which can help with early detection and decrease mortality and morbidity from colorectal cancer 3