That is one reason doctors may investigate the digestive system when iron deficiency cannot be explained by diet or another obvious cause.
Could These Symptoms Mean Something Other Than Cancer?
Absolutely.
This is one of the most important points to understand.
Constipation doesn't mean colon cancer.
Diarrhea doesn't mean colon cancer.
Hemorrhoids don't mean colon cancer.
Abdominal bloating doesn't mean colon cancer.
Even blood in the stool does not automatically mean cancer.
There are numerous benign and treatable conditions that can produce these symptoms.
The reason medical evaluation matters is that symptoms alone cannot reliably distinguish between harmless and serious causes.
Colon Polyps Can Matter Before Cancer Develops
Colorectal cancer often develops through a process in which certain abnormal growths, particularly adenomatous polyps and some serrated lesions, can gradually acquire changes that eventually lead to cancer.
Importantly, many polyps cause no symptoms at all.
That's why waiting for symptoms isn't a substitute for colorectal cancer screening.
During a colonoscopy, doctors can identify and remove certain precancerous polyps before they have the opportunity to progress.
This is one of the major reasons colorectal cancer screening can be so valuable.