Colon Cancer

Colon cancer occurs in the colon, or the large intestine that makes up the lower part of the digestive system. When colon cancer affects the last section of the colon, it is referred to as rectal cancer. Collectively, the cancers are often referred to as colorectal cancer or intestinal cancer. Colon cancer often develops from adenomatous polyps. These polyps are non-cancerous collections of cells in the colon. In some cases, polyps may not develop into cancer. However, colon cancer screening is recommended to identify polyps before they develop into colon cancer.

Colon Cancer Symptoms

The early stages of the condition often do not cause colon cancer symptoms in patients. When colon cancer symptoms appear, they vary depending on factors such as the size of the cancer and the location within the intestine. Patients who exhibit potential colon cancer symptoms should consult their doctor as soon as possible to discuss the possibility of colon cancer and undergo any recommended colon cancer testing.

Patients with colon cancer may exhibit the following colon cancer symptoms and signs:

  • Changes in bowel habits, such as diarrhea or constipation
  • Changes in stool size, shape, and consistency
  • Blood in the stool or rectal bleeding
  • Gas, cramps, pain, and other persistent abdominal discomfort
  • Weakness or fatigue that is not alleviated with adequate rest
  • Unexplained weight loss

Colon Cancer Diagnosis

According to the National Cancer Institute, more than 100,000 new cases of colon cancer and 40,000 cases of rectal cancer are diagnosed each year. Of these 140,000 new colorectal cancer cases, roughly 50,000 cancer-related deaths occur. These statistics show that colon cancer and colorectal cancer are aggressive conditions, and typically require aggressive and early treatment for positive outcomes. For this reason, colon cancer diagnosis is crucial for patient survival.

Colon cancer may be diagnosed with the following colon cancer testing:

  • Colonoscopy, a procedure which involves a flexible tube with an attached video camera. This tube, called an endoscope, is inserted through the rectum to identify abnormal conditions, diagnose colon cancer, and plan a treatment regimen for colon cancer patients.
  • CT, or computerized tomography scan. CT colonography, also called virtual colonoscopy, is a less invasive technique that uses radiation to create several pictures of the patient’s colon to observe and identify abnormalities which may indicate colon cancer.

Colon Cancer Diagnosis Errors

Due to the varying nature of colon cancer symptoms, the condition may cause misdiagnosis, delayed diagnosis, or complete failure to diagnose. A number of patients with colon cancer have been misdiagnosed with inflammatory bowel diseases (IBD) such as irritable bowel syndrome, diverticulitis, and colitis. Other conditions such as hemorrhoids may also be misdiagnosed. Likewise, patients with these conditions may be misdiagnosed as having colon cancer.

Irritable Bowel Syndrome (IBS) Misdiagnosis

Irritable bowel syndrome, or IBS, may exhibit symptoms similar to colon cancer. Patients with IBS may exhibit abdominal pain, fatigue, loss of appetite, and a swollen stomach. Patients who receive an IBS diagnosis and still experience persistent symptoms despite an IBS treatment regimen should speak with a physician who specializes in colon cancer.

Diverticulitis Misdiagnosis

Diverticulitis involves common digestive tract growths called diverticula. During diverticulitis, diverticula become infected or inflamed. This can lead to symptoms that are similar to colon cancer symptoms, such as severe abdominal pain, changes in bowel habits, and rectal bleeding. If a patient has been diagnosed with diverticulitis but does not respond to treatment, he or she should consult a colon specialist.

Ulcerative Colitis Misdiagnosis

Ulcerative colitis is another type of inflammatory bowel disease (IBD) that may be misdiagnosed as colon cancer or vice-versa. An ulcerative colitis misdiagnosis may be especially dangerous, as the condition has no known cure. Therefore, symptoms are typically chronic within the patient, creating difficulty in confirming whether or not the patient is receiving the proper treatment for the current medical condition. Ulcerative colitis symptoms depend on the location and severity of the condition. Ulcerative colitis symptoms may include rectal pain, rectal bleeding, abdominal cramps, and unexplained weight loss.

Hemorrhoids Misdiagnosis

Hemorrhoids, also called piles, are veins in the rectum and anus that become infected and swollen. Hemorrhoids may occur externally at the anal opening, or internally at the rectum. Internal hemorrhoids are most commonly associated with a potential colon cancer misdiagnosis. When left untreated, hemorrhoids can cause pain and discomfort, rectal bleeding, and itchiness.




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