Colonic polypectomy | |
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Specialty | Gastroenterology |
Uses | Removal of colorectal polyps |
Complications | bleeding, perforation, Postpolypectomy coagulation syndrome |
Approach | Cold forceps, cold snare, hot snare, endoscopic mucosal resection (EMR), endoscopic submucosal dissection (ESD) |
Colonic polypectomy is the removal of colorectal polyps in order to prevent them from turning cancerous.
Gastrointestinal polyps can be removed endoscopically through colonoscopy or esophagogastroduodenoscopy, or surgically if the polyp is too large to be removed endoscopically. The method used to perform colonic polypectomies during colonoscopy depends on the size, shape and histological type of the polyp to be removed. Prior to performing polypectomy, polyps can be biopsied and examined histologically to determine the need to perform polypectomy. [1] [2]
Prior to resection, assessment of the polyp should include: polyp size, morphology, location, and accessibility. [3] If there are features that suggest of cancer is present in the polyp, then either endoscopic submucosal dissection or surgery should be considered. [3] If the polyp appears benign, but the risk of progression to cancer is negligible, then resection is not necessary. [3]
Large sessile polyps are more difficult to remove endoscopically, and polypectomy in these cases has a higher risk of complication. Sessile polyps up to 10mm can often be removed by snare polypectomy. Polyps over 10mm may have to be removed piecemeal by snare polypectomy. The use of electrocautery over a large area has a significant risk of causing colonic perforation; to reduce this chance, and to facilitate the polypectomy, sterile fluid (saline or colloid, with methylene blue dye added) can be injected under the base of the polyp to raise it away from the muscular layers of the colon. [4]
Pedunculated polyps can be removed by snare polypectomy. When the polyp is identified, a polypectomy snare is passed over the polyp and around the stalk of the polyp. The loop of the snare is then tightened to grip the polyp stalk, and the polyp is pulled away from the wall of the colon. An electric current is then passed through the snare loop to cut through the polyp stalk, providing electrocautery at the same time. The polyp can then be retrieved using the snare or an endoscopy basket, and removed by withdrawing the colonoscope.
Polyps may be removed using cold biopsy forceps, cold snare polypectomy, hot biopsy forceps, hot snare polypectomy, endoscopic mucosal resection, or endoscopic submucosal dissection. Cold biopsy forceps may be used for small (diminutive) polyps 1-3 mm in size. [3] Cold snare polypectomy has the advantage of avoiding the risk of delayed bleeding, postpolypectomy coagulation syndrome, and perforation. [3]
The most common complications of colonic polypectomy are bleeding and colonic perforation. Rarely, postpolypectomy coagulation syndrome may occur following removal of large polyps with electrocautery. [5]
Gastroenterology is the branch of medicine focused on the digestive system and its disorders. The digestive system consists of the gastrointestinal tract, sometimes referred to as the GI tract, which includes the esophagus, stomach, small intestine and large intestine as well as the accessory organs of digestion which include the pancreas, gallbladder, and liver.
An endoscopy is a procedure used in medicine to look inside the body. The endoscopy procedure uses an endoscope to examine the interior of a hollow organ or cavity of the body. Unlike many other medical imaging techniques, endoscopes are inserted directly into the organ.
Colonoscopy or coloscopy is a medical procedure involving the endoscopic examination of the large bowel (colon) and the distal portion of the small bowel. This examination is performed using either a CCD camera or a fiber optic camera, which is mounted on a flexible tube and passed through the anus.
In anatomy, a polyp is an abnormal growth of tissue projecting from a mucous membrane. If it is attached to the surface by a narrow elongated stalk, it is said to be pedunculated; if it is attached without a stalk, it is said to be sessile. Polyps are commonly found in the colon, stomach, nose, ear, sinus(es), urinary bladder, and uterus. They may also occur elsewhere in the body where there are mucous membranes, including the cervix, vocal folds, and small intestine. Some polyps are tumors (neoplasms) and others are non-neoplastic, for example hyperplastic or dysplastic, which are benign. The neoplastic ones are usually benign, although some can be pre-malignant, or concurrent with a malignancy.
A lower gastrointestinal series is a medical procedure used to examine and diagnose problems with the human colon of the large intestine. Radiographs are taken while barium sulfate, a radiocontrast agent, fills the colon via an enema through the rectum.
Esophagogastroduodenoscopy (EGD) or oesophagogastroduodenoscopy (OGD), also called by various other names, is a diagnostic endoscopic procedure that visualizes the upper part of the gastrointestinal tract down to the duodenum. It is considered a minimally invasive procedure since it does not require an incision into one of the major body cavities and does not require any significant recovery after the procedure. However, a sore throat is common.
Radiation proctitis or radiation proctopathy is a condition characterized by damage to the rectum after exposure to x-rays or other ionizing radiation as a part of radiation therapy. Radiation proctopathy may occur as acute inflammation called "acute radiation proctitis" or with chronic changes characterized by radiation associated vascular ectasiae (RAVE) and chronic radiation proctopathy. Radiation proctitis most commonly occurs after pelvic radiation treatment for cancers such as cervical cancer, prostate cancer, bladder cancer, and rectal cancer. RAVE and chronic radiation proctopathy involves the lower intestine, primarily the sigmoid colon and the rectum, and was previously called chronic radiation proctitis, pelvic radiation disease and radiation enteropathy.
Fundic gland polyposis is a medical syndrome where the fundus and the body of the stomach develop many fundic gland polyps. The condition has been described both in patients with familial adenomatous polyposis (FAP) and attenuated variants (AFAP), and in patients in whom it occurs sporadically.
Argon plasma coagulation (APC) is a medical endoscopic procedure used to control bleeding from certain lesions in the gastrointestinal tract. It is administered during esophagogastroduodenoscopy or colonoscopy.
An endoclip is a metallic mechanical device used in endoscopy in order to close two mucosal surfaces without the need for surgery and suturing. Its function is similar to a suture in gross surgical applications, as it is used to join together two disjointed surfaces, but, can be applied through the channel of an endoscope under direct visualization. Endoclips have found use in treating gastrointestinal bleeding, in preventing bleeding after therapeutic procedures such as polypectomy, and in closing gastrointestinal perforations. Many forms of endoclips exist of different shapes and sizes, including two and three prong devices, which can be administered using single use and reloadable systems, and may or may not open and close to facilitate placement.
Hiromi Shinya was a Japanese-born general surgeon. He pioneered modern colonoscopic techniques, and invented the electrosurgical polypectomy snare now common on colonoscopes, allowing for removal of colon polyps without invasive surgery.
A colorectal polyp is a polyp occurring on the lining of the colon or rectum. Untreated colorectal polyps can develop into colorectal cancer.
An intracolonic explosion or colonic gas explosion is an explosion inside the colon of a person due to ignition of explosive gases such as methane. This can happen during colonic exploration, as a result of the electrical nature of a colonoscope.
Therapeutic endoscopy is the medical term for an endoscopic procedure during which treatment is carried out via the endoscope. This contrasts with diagnostic endoscopy, where the aim of the procedure is purely to visualize a part of the gastrointestinal, respiratory or urinary tract in order to aid diagnosis. In practice, a procedure which starts as a diagnostic endoscopy may become a therapeutic endoscopy depending on the findings, such as in cases of upper gastrointestinal bleeding, or the finding of polyps during colonoscopy.
The non-lifting sign is a finding on endoscopic examination that provides information on the suitability of large flat or sessile colorectal polyps for polypectomy by endoscopic mucosal resection (EMR). When fluid is injected under a polyp in preparation for endoscopic mucosal resection, some polyps do not "lift", indicating that the polyp is not separating from the submucosa. This makes polypectomy more technically difficult, and increases the risk of intestinal perforation if polypectomy is then attempted. It is also thought to be indicative of an early colorectal cancer that has invaded the submucosa significantly, which would make surgical removal of the tumour preferable to allow complete removal of the cancer. Consequently, the non-lifting sign is generally considered to be a contraindication to performing endoscopic mucosal resection.
Endoscopic mucosal resection is a technique used to remove cancerous or other abnormal lesions found in the digestive tract. It is one method of performing a mucosectomy.
Endoscopic submucosal dissection (ESD) is an advanced surgical procedure using endoscopy to remove gastrointestinal tumors that have not entered the muscle layer. ESD may be done in the esophagus, stomach or colon. Application of endoscopic resection (ER) to gastrointestinal (GI) neoplasms is limited to lesions with no risk of nodal metastasis. Either polypectomy or endoscopic mucosal resection (EMR) is beneficial for patients because of its low level of invasiveness. However, to ensure the curative potential of these treatment modalities, accurate histopathologic assessment of the resected specimens is essential because the depth of invasion and lymphovascular infiltration of the tumor is associated with considerable risk for lymph node metastasis. For accurate assessment of the appropriateness of the therapy, en bloc resection is more desirable than piecemeal resection. For a reliable en bloc resection of GI neoplasms, a new method of ER called endoscopic submucosal dissection (ESD) has been developed.
Serrated polyposis syndrome (SPS), previously known as hyperplastic polyposis syndrome, is a disorder characterized by the appearance of serrated polyps in the colon. While serrated polyposis syndrome does not cause symptoms, the condition is associated with a higher risk of colorectal cancer (CRC). The lifelong risk of CRC is between 25 and 40%. SPS is the most common polyposis syndrome affecting the colon, but is under recognized due to a lack of systemic long term monitoring. Diagnosis requires colonoscopy, and is defined by the presence of either of two criteria: ≥5 serrated lesions/polyps proximal to the rectum, or >20 serrated lesions/polyps of any size distributed throughout the colon with 5 proximal to the rectum.
Juvenile polyps are a type of polyp found in the colon. While juvenile polyps are typically found in children, they may be found in people of any age. Juvenile polyps are a type of hamartomatous polyps, which consist of a disorganized mass of tissue. They occur in about two percent of children. Juvenile polyps often do not cause symptoms (asymptomatic); when present, symptoms usually include gastrointestinal bleeding and prolapse through the rectum. Removal of the polyp (polypectomy) is warranted when symptoms are present, for treatment and definite histopathological diagnosis. In the absence of symptoms, removal is not necessary. Recurrence of polyps following removal is relatively common. Juvenile polyps are usually sporadic, occurring in isolation, although they may occur as a part of juvenile polyposis syndrome. Sporadic juvenile polyps may occur in any part of the colon, but are usually found in the distal colon. In contrast to other types of colon polyps, juvenile polyps are not premalignant and are not usually associated with a higher risk of cancer; however, individuals with juvenile polyposis syndrome are at increased risk of gastric and colorectal cancer., Unlike juvenile polyposis syndrome, solitary juvenile polyps do not require follow up with surveillance colonoscopy.
Postpolypectomy coagulation syndrome is a condition that occurs following colonoscopy with electrocautery polypectomy, which results in a burn injury to the wall of the gastrointestinal tract. The condition results in abdominal pain, fever, elevated white blood cell count and elevated serum C-reactive protein.