what are the symptoms of rectal cancer
Rectal cancer can cause subtle symptoms at first, then more obvious changes in your bowel habits, bleeding, and general health as it progresses.
Key symptoms to watch for
- Rectal bleeding or blood in stool (bright red, dark red, or making stool look very dark).
- A change in bowel habits lasting more than a few days (diarrhea, constipation, or going more often than usual).
- Feeling that your bowel does not empty completely, or a persistent urge to have a bowel movement even after going.
- Narrow or “pencil‑thin” stools compared with your usual stool shape.
- Abdominal or pelvic pain, cramping, bloating, or discomfort during bowel movements or when sitting.
- Blood or mucus mixed with stool.
- Unintentional weight loss or loss of appetite.
- Unexplained weakness, tiredness, or a diagnosis of iron‑deficiency anemia.
- Occasionally, a lump in the rectum found on exam.
Simple symptom table (HTML)
| Symptom | How it may appear | Why it matters |
|---|---|---|
| Rectal bleeding / blood in stool | [9][3][5][1]Blood on toilet paper, in the bowl, or mixed with stool | Common early warning sign that should always be checked |
| Change in bowel habits | [10][3][5][1]New diarrhea, constipation, or going more often for > a few days | Tumor can alter how stool passes through the rectum |
| Feeling of incomplete emptying / constant urge | [3][5][10][1]“I still feel like I need to go” even right after a bowel movement | Mass in the rectum can create pressure or blockage |
| Narrow or pencil‑thin stool | [5][7][1]Stool thinner than usual, sometimes for weeks | Tumor may narrow the rectal passage |
| Abdominal or pelvic pain / cramping | [7][10][1][3][5]Ongoing discomfort, especially with bowel movements or sitting | Can signal more advanced or locally irritating disease |
| Unintentional weight loss | [10][1][3][5][7]Clothes getting looser without dieting | Body may be using more energy fighting cancer |
| Fatigue / weakness / anemia | [1][3][5][7]Unusual tiredness, shortness of breath, low iron tests | Slow blood loss from the tumor can cause iron‑deficiency anemia |
Important cautions
- Rectal cancer can cause few or no symptoms early on, so screening (like colonoscopy) is important from recommended ages or earlier if you have risk factors.
- Hemorrhoids, infections, and other benign conditions can cause similar symptoms, but you should never assume that bleeding or persistent bowel changes are harmless.
If you have any of these symptoms, especially rectal bleeding, a change in bowel habits lasting more than a couple of weeks, or unexplained weight loss or fatigue, you should contact a doctor or urgent care as soon as you can for proper evaluation.
This information is general and cannot replace in‑person medical advice. If symptoms are moderate to severe (heavy bleeding, strong pain, dizziness, or feeling very unwell), seek urgent or emergency care immediately.
Information gathered from public forums or data available on the internet and portrayed here.