What are the key points in diagnosing colorectal cancer

Colorectal cancer is a common malignant tumor, including colon cancer and rectal cancer. Cancer that occurs between the dentate line and the junction of the rectum and the sigmoid colon is called rectal cancer, and cancer that occurs in the ascending colon, transverse colon, descending colon and sigmoid colon is called colon cancer. It is one of the common malignant tumors of the digestive tract. Let's take a look at the key points of colorectal cancer diagnosis.

1. Left-sided colon cancer: Since the sigmoid colon is the narrowest and the stool in the left colon has become solid, left-sided colon cancer mainly manifests as chronic progressive intestinal obstruction or intractable constipation. Abdominal distension, abdominal pain, and borborygmus are more obvious. The rupture of the tumor can cause blood and mucus to adhere to the surface of the stool. Sometimes, fresh blood in the stool is easily misdiagnosed as simple constipation in the early stage.
2. Right-sided colon cancer: The main symptoms are indigestion, discomfort in the right upper abdomen, irregular bowel movements, abdominal pain and abdominal masses. The disease gradually progresses and progressive anemia, weight loss, fever, etc. It is often misdiagnosed as colitis, intestinal tuberculosis, chronic appendicitis, Crohn's disease and cholecystitis.
3. Rectal cancer: The main symptoms of rectal cancer are increased bowel movements and a feeling of unclear bowel movements. The stool becomes thinner and contains blood and mucus. If the cancer invades the sacral plexus nerves, severe pain may occur, and intestinal obstruction may occur in the late stage. The cancer may affect the bladder and prostate, causing hematuria, frequent urination, and difficulty urinating.
4. Anal cancer is mainly manifested by blood in the stool and pain during defecation. The cancer invades the anal sphincter and can cause fecal incontinence.