Blood in the stool, is it definitely hemorrhoids? It could be rectal cancer

Author: Li Zhenpeng Zhengzhou Central Hospital

Reviewer: Gao Lei, Chief Physician, Zhengzhou Central Hospital

Frequent stomach pain, increased bowel movements, and blood in the stool, is it because of a bad stomach? Is it hemorrhoids? Or is it a serious illness? In this case, it may be a symptom of rectal cancer, and you need to go to the hospital for treatment in time.

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1. Classification of rectal cancer by location

According to the location of rectal cancer lesions, they can be divided into high, middle and low rectal cancer. The lowest edge of the high rectal cancer lesion is more than 10 cm away from the anal verge; the lowest edge of the middle lesion is 5 to 10 cm away from the anal verge; the lowest edge of the low lesion is less than 5 cm away from the anal verge. Among them, low rectal cancer is often confused with hemorrhoids because it is close to the anus and prone to bleeding, but it can be preliminarily diagnosed during the doctor's rectal digital examination.

2. Diagnosis of rectal cancer

So, how to diagnose rectal cancer? For patients suspected of colon cancer, the following examinations are recommended:

① Serum tumor marker testing, such as carcinoembryonic antigen (CEA), carbohydrate antigen 19-9 (CA19-9), etc. The increase of corresponding indicators is helpful in determining whether it is a malignant tumor and evaluating the progression of the disease.

②Imaging examination: CT and MRI are commonly used. CT can show the location, size, shape, invasion range and whether the tumor has distant metastasis; MRI is important for determining the preoperative staging of rectal cancer and whether there is lymph node metastasis.

③Endoscopic biopsy, taking the diseased tissue through colonoscopy for pathological examination is the gold standard for diagnosing rectal cancer.

How to determine the stage of confirmed rectal cancer? At present, the staging of rectal cancer is based on the TNM standard, where T represents the level of intestinal invasion reached by the tumor, N represents whether there is lymph node metastasis, and M represents whether there is metastasis to distant organs. Generally speaking, in the early stage of rectal cancer, the depth of tumor infiltration is limited to the mucosa and submucosal layer, and there is no lymph node metastasis; in the middle stage, lymph node metastasis occurs; and in the late stage, distant organ metastasis occurs.

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3. Treatment of rectal cancer

(1) For early rectal cancer with tumor infiltration limited to the mucosa and submucosal layer, endoscopic resection can be selected, with the main options being endoscopic mucosal resection (EMR) or endoscopic submucosal dissection (ESD). It is recommended to perform colonoscopy regularly at 3, 6, and 12 months after endoscopic treatment. If there are no abnormalities during follow-up, regular follow-up can be performed every year thereafter. If residual tumor or recurrence is found, timely medical treatment should be sought for systemic treatment.

(2) If the following situations occur: endoscopic treatment results show a positive vertical resection margin, the tumor infiltrates at least 1 mm below the mucosa, vascular invasion is positive, poorly differentiated adenocarcinoma, signet ring cell carcinoma, or mucinous carcinoma, and cancer has been confirmed but a whole tumor biopsy has not been performed, then radical surgery should be performed.

There are several main surgical radical resection options for rectal cancer: abdominal anterior resection, mainly including anterior resection completed through the abdomen (Dixon procedure), intestinal dragging out through the anus, two-stage resection and dragging out the intestine (Bacon procedure), abdominal resection and one-stage anastomosis near the dentate line (Parks procedure), resection of part or all of the internal sphincter between the internal and external sphincters, anastomosis near the dentate line (ISR procedure), and extended radical resection of colorectal cancer with lateral lymph node clearance. The above procedures are briefly summarized as follows: After resection of the lesion, the proximal and distal ends of the intestine or near the dentate line are anastomosed to establish a normal defecation channel. During the operation, preventive ileostomy is performed depending on the situation, and the stoma is restored after good recovery in the later stage, so as to achieve the ultimate anal preservation effect for low-position rectal cancer.

If the tumor is large or involves the anal canal, an abdominoperineal resection, also known as the Miles procedure, is required. This involves removing the rectum and anus and creating a permanent artificial anus (stoma) in the abdomen. The patient will have to carry a fecal bag for the rest of his life.

Clinically, we may encounter cases of poor general condition, acute obstruction, perforation caused by tumors, and extensive invasion of the pelvic cavity by rectal cancer. In this case, we can choose transabdominal rectal cancer resection, proximal stoma, and distal closure, which is the Hartmann operation.

If the tumor is in a very late stage and distant metastasis occurs, you can seek help from the Department of Oncology or the Department of Radiotherapy for systematic chemotherapy and radiotherapy.

In short, rectal cancer is not scary. Knowing it, understanding it, and combining it with comprehensive tumor treatment can maximize the effectiveness of tumor treatment and reduce damage to the body.