肠息肉

March 30, 2019

Definition

肠息肉是small, mushroom-like abnormalities of the intestine that may have a stalk or be flat with a stalk. They can vary from under 2 millimeters (less than 1/10 of an inch) to over 2 inches in diameter.

Description

Certain sporadic (not inherited) intestinal polyps are a risk factor forcolorectal cancer. These polyps - chiefly those classified as adenomas (growths with gland-like characteristics) - are benign, but they may become cancerous, particularly if they grow larger than an inch in diameter.

In most cases, colorectal polyps do not cause symptoms; however, they can cause intermittent bleeding or the passage of mucus with bowel movements. If they are large, they can obstruct the passage of waste material.

Adenomas占所有结肠直肠息肉的约70％作为结肠镜检查的一部分。腺瘤以50岁以上所有成年人的30％出现.They arise most often in the rectum and sigmoid colon.

当它们在将息肉头部的茎上生长到肠道壁的茎上时，腺瘤被描述为致命的。平坦的息肉直接在肠道上生长的息肉被称为无柄。

About 85 percent are tubular (growing in microscopic tube-like patterns); 5 percent are villous (forming finger-like projections, or fronds); and 10 percent are tubulovillous (intermediate structures that contain both growth patterns). These polyps differ in their structure, texture, and microscopic characteristics; they also differ in their potential for cancerous change.

侵入性癌症develops in roughly 5 percent of all tubular (also called adenomatous) polyps. Villous polyps are less common, but about 40 percent of them become cancerous. Cancer develops in about 22 percent of all tubulo-villous polyps. The most common colorectal types, called hyperplastic polyps or hyperplastic mucosal tags, are harmless.

Scientists believe that many cancers of the large bowel arise from polyps. Thus removing these growths (polypectomy), often through a sigmoidoscope or colonoscope, is one way to prevent colorectal cancer. Because new polyps develop in nearly half of all patients who have had such growths removed, careful follow-up is necessary.

原因

Family History：结肠息肉患者的兄弟姐妹和父母正在增加结肠癌的风险增加，特别是当息肉在60岁之前或 - 在兄弟姐妹的情况下 - 当父母患有结肠癌时。

Diet: About 90 percent of all colon cancers arise from polyps in the colon. If doctors could prevent polyps from occurring in the first place, they could reduce the incidence of cancer. In general, most physicians encourage people to eat a low-fat, high-fiber diet, to eat more fruits, vegetables, chicken and fish, and to eat less red meat.

抽烟: Smoking may also be a risk factor for colon cancer.

Obesity: In some studies, higher body mass was positively associated with an increased risk of adenomas leading to colon cancer.

症状

Many polyps are asymptomatic; the larger the lesion, the more likely it is to cause symptoms. Rectal bleeding is by far the most frequent complaint. Blood is bright red or dark red, depending on the location of the polyp, and bleeding is usually intermittent.

Some polyps, notably large villous adenomas, may secrete copious amounts of mucus that are released through the rectum.

Diagnosis

当一个人的症状表明，在结肠或直肠中可能存在癌前或癌症生长，医生会询问患者的病史，然后进行完整的考试。

In addition to checking the general signs of health (temperature, pulse and blood pressure) the doctor usually performs the following tests:

First, the doctor will insert a lubricated and gloved finger into the rectum to gently feels for any bumps. The fecal occult blood test is done on a stool sample to find if there is blood in the stool. For this test, the patient places a small amount of stool on a plastic slide or piece of special paper. The sample is then sent to a lab to be examined. If performed at home, three samples are usually taken.

医生还可以进行柔性族体镜检查，看看肠果的直肠和下端。对于此考试，将薄型的柔性仪器，末端的灯，称为锯齿镜，插入直肠。在这些步骤之后，医生可能推荐结肠镜检查。

A colonoscopy enables the doctor to see the entire length of the colon. For this exam, the doctor uses a colonoscope, which a thin, flexible tube with a light at the end. If a polyp is found, the doctor will remove a tissue (biopsy) for examination at a lab.

治疗

结肠和直肠的息肉是治疗的，因为它们产生症状，因为它们可能在第一次发现时是恶性的，或者因为它们可能在以后变得恶性。

可以通过刚性或柔性六样镜通过的电陶器圈套去除小息肉，但由于在所有息肉的所有患者中建议使用总结肠镜检查，因此最好在该过程中等待并在制备良好的结肠中进行多药物切除术。

直肠上的大型，无柄，柔软，天鹅绒般的病变通常是绒毛腺瘤，这些肿瘤具有很高的恶性潜力，必须完全切除。随着患者麻醉的，这可以通过大多数情况下通过肛门完成。

应用活检钳或通过结肠镜通过的活检钳或电烙术·斯内纳，去除乙状息肉和上述小的息肉病变。

Depending on your medical history, age and risk factors, your physician will recommend how often to screen for colon cancer, including how often you should perform the fecal occult blood test and how frequently you should have a flexible sigmoidoscopy, colonoscopy, or other tests performed.