Colon cancer also called colorectal cancer or bowel cancer includes cancerous growths in
the colon, rectum and appendix. It is the third most common form of cancer and the second leading cause of
death among cancers in the Western world.
Many colorectal cancers are thought to arise from adenomatous polyps
in the colon. These mushroom-like growths are usually benign, but some may develop into cancer over time.
The majority of the time, the diagnosis of localized Colon Cancer is through colonoscopy. Therapy is usually
through surgery, which in many cases is followed by chemotherapy.
The symptomology of colorectal cancer depends on the site of the lesion. Generally speaking, the nearer is
it to the anus, the more bowel symptoms will there be, such as:
Change in bowel habits
change in frequency [(constipation and/or (spurious) diarrhoea),
change in the caliber of stools
change in consistency of stools
Bloody stools (hematochezia) or per rectal bleeding
Stools with mucus
Tarry stools (melena)
Tenesmus (only associated with rectal cancer)
Bowel obstruction (rare) by the tumor
Especially in the cases of cancer in the ascending colon, sometimes only the less specific constitutional
symptoms will be found:
Anemia, with symptoms such as dizziness, malaise and palpitations.
Clinically there will be pallor and
complete blood picture will confirm the low hemoglobin level.
Anorexia
Asthenia
Unexplained weight loss.
There may also be symptoms attributed to distant metastasis:
Shortness of breath as in lung metastasis
Epigastric or right upper quadrant as in liver metastasis.
Rarely can there be jaundice if the secondary
lesion compromises the bile outflow. Clinically there might be hepatomegaly.
It is also possible that the
patient remains asymptomatic.
This is one reason why many organizations recommend periodic screening for
the disease with fecal occult blood testing and colonoscopy.
