How much do you know about colorectal cancer through digital anal examination

Digital rectal examination is a simple but very important examination method in which the doctor inserts a sterile gloved finger into the anus to check for diseases. It is the main screening method for early colorectal cancer.

A domestic statistics in my country shows that more than 80% of rectal cancer patients can be found to have lesions during digital rectal examination. If they adopt the left-lying position, the cancer at a higher position can be palpated. About 50% of colorectal cancer patients can be preliminarily diagnosed through a simple digital rectal examination. Even some patients with abnormal bowel habits such as bloody stools, frequent stools, mucus in the stool, and tenesmus should undergo a digital rectal examination.

Digital rectal examination is simple to perform and can detect the presence and nature of lesions in the anus and rectum within 7 to 10 cm from the anal margin. If the patient is instructed to hold his breath or do other maneuvers to increase abdominal pressure, lesions in higher locations can also be detected.

When performing anal examination, the doctor should first press the index finger lightly on the posterior wall of the anus to relieve the patient's discomfort caused by the contraction of the radiating anal sphincter, and then ask the patient to take a deep breath.

Most cases of rectal cancer feel flat, hard, oval or ring-shaped, with raised edges and sunken centers. Sometimes they are cauliflower-shaped hard masses that protrude into the intestinal cavity. When examining rectal cancer in men, pay attention to its relationship with the prostate, and in women, pay attention to its relationship with the posterior vaginal wall. When the surface of the tumor is prone to ulceration, the finger cot is often stained with blood and mucus.

Patients with negative rectal examination results should undergo fecal occult blood test if they have other discomfort symptoms, and X-ray and endoscopy if necessary. Patients with positive rectal examination results should undergo endoscopy, cytology or biopsy for further pathological examination.