Relationship between indeterminate or positive lateral margin and local recurrence after endoscopic resection of colorectal polyps.

BACKGROUND AND STUDY AIMS: Although endoscopic resection is widely used for the treatment of superficial colorectal neoplasms, the rate of local recurrence of lesions with a positive or indeterminate lateral margin on histologic evaluation is unclear. We aimed to demonstrate the relationship between lateral margin status and local recurrence after the endoscopic resection of intramucosal colorectal neoplasms. PATIENTS AND METHODS: We retrospectively collected the clinical and pathologic data for 844 endoscopically resected colorectal intramucosal neoplasms with a size of 10 mm or larger. We investigated the relationship between the local recurrence rate and the lateral margin status (categorized as LM0 [negative], LM1 [positive], or LMX [indeterminate]). RESULTS: In total, 389 lesions were evaluated as LM0 and showed no local recurrence. Of the 455 lesions evaluated as LMX or LM1, 30 showed local recurrence within a median period of 6.3 months (range, 1.7 - 48.1) from the initial endoscopic resection. The local recurrence rate of the en bloc-LMX group (2.2 %) was significantly lower than that of the piecemeal-LMX group (15.2 %). Of the 30 cases of recurrence, 28 were successfully treated with a second endoscopic resection. Of the two lesions that showed further recurrence, one was treated with a third endoscopic resection, whereas the other - which was a piecemeal-LMX lesion - was eventually diagnosed as invasive cancer and treated with surgery. CONCLUSIONS: The local recurrence rate was lower in the en bloc-LMX group than in the piecemeal-LMX group. Thus, we believe that en bloc-LMX lesions that are completely and confidently resected endoscopically can be treated as en bloc-LM0 lesions.

Endoscopic submucosal dissection for colorectal neoplasms: a review.

The introduction of colorectal endoscopic submucosal dissection (ESD) has expanded the application of endoscopic treatment, which can be used for lesions with a low metastatic potential regardless of their size. ESD has the advantage of achieving en bloc resection with a lower local recurrence rate compared with that of piecemeal endoscopic mucosal resection. Moreover, in the past, surgery was indicated in patients with large lesions spreading to almost the entire circumference of the rectum, regardless of the depth of invasion, as endoscopic resection of these lesions was technically difficult. Therefore, a prime benefit of ESD is significant improvement in the quality of life for patients who have large rectal lesions. On the other hand, ESD is not as widely applied in the treatment of colorectal neoplasms as it is in gastric cancers owing to the associated technical difficulty, longer procedural duration, and increased risk of perforation. To diversify the available endoscopic treatment strategies for superficial colorectal neoplasms, endoscopists performing ESD need to recognize its indications, the technical issues involved in its application, and the associated complications. This review outlines the methods and type of devices used for colorectal ESD, and the training required by endoscopists to perform this procedure.

Endoscopic submucosal dissection for colorectal neoplasms.

Endoscopic submucosal dissection (ESD) is an established therapeutic technique for the treatment of gastrointestinal neoplasms. Because it is typically completed as en bloc resection, this technique provides a complete specimen for precise pathological evaluation. On the other hand, ESD is not as widely applied in treating colorectal neoplasms as with gastric cancers, due to its technical difficulty, longer procedure time, and increased risk of perforation. However, some devices that facilitate ESD and improve the safety of the procedure have been recently reported, and the use of the technique has gradually spread worldwide. Endoscopists who begin to perform ESD need to recognize the indications of ESD, the technical issue involved in this procedure, and its associated complications. This review outlines the methods and certain types of devices used for colorectal ESD.

Colorectal endoscopic submucosal dissection: Technical advantages compared to endoscopic mucosal resection and minimally invasive surgery.

BACKGROUND AND AIM: In recent years, the effectiveness of colorectal endoscopic submucosal dissection (ESD) has been increasingly reported. Herein, we highlight the most recent developments and technical advantages of colorectal ESD compared to EMR and minimally invasive surgery. METHODS: All candidate lesions for ESD were confirmed as being intramucosal tumors by colonoscopy. Presently, the indications for colorectal ESD approved by the Japanese government's medical insurance system are early colorectal cancers with a maximum tumor size of 2-5 cm; however, many early cancers >5 cm have been treated by ESD in referral centers. RESULTS: The primary advantage of ESD compared to endoscopic mucosal resection (EMR) is a higher en-bloc resection rate for large colonic tumors that had previously been treated by surgery. ESD has several advantages compared to other therapeutic modalities, such as being a safer technique and providing better quality of life. For rectal cancer treatment, a longer procedure time is required for laparoscopic assisted colectomy, whereas trans-anal resection and trans-anal endoscopic microsurgery are more invasive than ESD with a significantly higher recurrence rate. Accordingly, ESD is the preferred choice for early colorectal cancers when there is no risk of lymph-node metastasis. CONCLUSION: ESD is an effective procedure for treating non-invasive non-polypoid colorectal tumors. These tumors may be difficult to resect en bloc by conventional EMR. The use of ESD results in a higher en-bloc resection rate and is less invasive than surgery.

Indications for and technical aspects of colorectal endoscopic submucosal dissection.

Due to the widespread acceptance of gastric and esophageal endoscopic submucosal dissections (ESDs), the number of medical facilities that perform colorectal ESDs has grown and the effectiveness of colorectal ESD has been increasingly reported in recent years. The clinical indications for colorectal ESD at the National Cancer Center Hospital, Tokyo, Japan include laterally spreading tumor (LST) nongranular type lesions >20 mm and LST granular type lesions >30 mm. In addition, 0-IIc lesions >20 mm, intramucosal tumors with nonlifting signs and large sessile lesions, all of which are difficult to resect en bloc by conventional endoscopic mucosal resection (EMR), represent potential candidates for colorectal ESD. Rectal carcinoid tumors less than 1 cm in diameter can be treated simply, safely, and effectively by endoscopic submucosal resection using a ligation device and are therefore not indications for ESD. The en bloc resection rate was 90%, and the curative resection rate was 87% for 806 ESDs. The median procedure time was 60 minutes, and the mean size for resected specimens was 40 mm (range, 15 to 150 mm). Perforations occurred in 23 (2.8%) cases, and postoperative bleeding occurred in 15 (1.9%) cases, but only two perforation cases required emergency surgery (0.25%). ESD was an effective procedure for treating colorectal tumors that are difficult to resect en bloc by conventional EMR. ESD resulted in a higher en bloc resection rate as well as decreased invasiveness in comparison to surgery. Based on the excellent clinical results of colorectal ESDs in Japan, the Japanese healthcare insurance system has approved colorectal ESD for coverage.

A case of a duodenal gastrointestinal stromal tumor diagnosed with the aid of diffusion-weighted magnetic resonance imaging.

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumor of gastrointestinal tract, and bleeding is among the primary symptoms. If the tumor is located in the small intestine, diagnosis might be difficult because of its inaccessibility by endoscope. This report presents a case of duodenal GIST diagnosed with the aid of diffusion-weighted (DW) magnetic resonance imaging (MRI). A 66-year-old male was admitted to the hospital because of shortness of breath and melena. The patient demonstrated marked anemia. Esophagogastroduodenoscopy and colonoscopy revealed no involvement of the mucosa of the gastrointestinal tract in regard to the observed bleeding. Thereafter, computed tomography was done and showed a tumorous lesion 4.2 cm in diameter located around the ligament of Treitz. The area showed significant high intensity by DW-MRI, strongly suggesting malignant character. Examination with a long endoscope demonstrated a large submucosal tumor with wide ulceration located at the third portion of the duodenum. The biopsy sample contained spindle-shaped cells that were positive for CD34 and c-kit on histochemistry, and the tumor was diagnosed as GIST. The patient underwent surgery and survived for 16 months without any recurrence.