Clinical manifestations of colon cancer

The clinical manifestations of colon cancer are as follows:

1. Symptoms

(1) Changes in bowel habits, such as constipation or diarrhea, are early symptoms and are more common in distal lesions.

(2) Bleeding is the most common symptom of colon cancer. It can manifest as occult bleeding (common in right-sided colon lesions) or obvious bleeding, ranging from obvious red to dark purple to black.

(3) Abdominal pain is often vague and difficult to locate. If the patient has intestinal obstruction, it is accompanied by abdominal distension, nausea and even vomiting. It can also manifest as colic and back pain, which often occurs when the retroperitoneal tissue is invaded.

(4) Atypical systemic symptoms include weight loss, deterioration of general condition, anemia, and occasional fever, which are manifestations of disease progression.

(5) Acute symptoms, such as intestinal obstruction, perforation or massive bleeding, are less common. About 15% of patients experience acute intestinal obstruction, usually with lesions in the left colon, dry stools, and circular lesions. Perforation caused by colon cancer can lead to peritonitis and abscess formation. The most common site of perforation is the tumor site, caused by the tumor penetrating the intestinal wall. Obstruction may occur first, followed by perforation in the cecum. Perforation can also occur with inflammatory diseases such as diverticulitis, appendicitis, or Crohn's disease.

2. Signs Abdominal examination usually fails to reveal meaningful signs. A palpable mass usually indicates a large tumor or metastasis, or cancer. The liver may be enlarged and irregular. Ascites and enlarged inguinal and left supraclavicular lymph nodes are rarely found, and some patients may even present with unexplained fever.