Endoscopic submucosal dissection vs endoscopic mucosal resection for colorectal tumors: A meta-analysis

AIM: To compare the efficacy and safety of endoscopic submucosal dissection (ESD) and endoscopic mucosal resection (EMR) for the treatment of colorectal tumors.

METHODS: Databases, such as PubMed, EMBASE, Cochrane Library and Science Citation Index updated to 2013 were searched to include eligible articles. In the meta-analysis, the main outcome measurements were the en bloc resection rate, the histological resection rate and the local recurrence rate. Meanwhile, we also compared the operation time and the incidence of procedure-related complications.

RESULTS: Six trials were identified and a total of 1642 lesions were included. The en bloc resection rate was higher and the local recurrence rate was lower in the ESD group compared with the EMR group (OR = 7.94; 95%CI: 3.96-15.91; OR = 0.09; 95%CI: 0.04-0.19). There was no significant difference in histological resection rate(OR = 1.65; 95%CI: 0.29-9.30) and procedure-related complication rate between the two groups (OR = 1.59; 95%CI: 0.92-2.73). The meta-analysis also showed that ESD was more time consuming than EMR.

CONCLUSION: Compared with EMR, ESD results in higher en bloc resection rate and lower local recurrence rate for the treatment of colorectal tumors, without increasing the procedure-related complications.

Risk factors for local recurrence after en bloc endoscopic submucosal dissection for early gastric cancer

AIM: To investigate factors related to recurrence following en bloc resection using endoscopic submucosal dissection (ESD) in patients with early gastric cancer (EGC).

METHODS: A total of 1121 patients (1215 lesions) who had undergone ESD for gastric neoplasia between April 2003 and May 2010 were retrospectively reviewed. Data from 401 patients (415 lesions) were analyzed, following the exclusion of those who underwent piecemeal resection, with deep resection margin invasion or lateral margin infiltration, and diagnosed with benign lesions.

RESULTS: Local recurrence after en bloc ESD was found in 36 cases (8.7%). Unclear resection margins, long procedure times, and narrow safety margins were identified as risk factors for recurrence. Lesions located in the upper third of the stomach showed a higher rate of recurrence than those located in the lower third of the stomach (OR = 2.9, P = 0.03). The probability of no recurrence for up to 24 mo was 79.9% in those with a safety resection margin ≤ 1 mm and 89.5% in those with a margin > 1 mm (log-rank test, P = 0.03).

CONCLUSION: Even in cases in which en bloc ESD is performed for EGC, local recurrence still occurs. To reduce local recurrences, more careful assessment will be needed prior to the implementation of ESD in cases in which the tumor is located in the upper third of the stomach. In addition, clear identification of tumor boundaries as well as the securing of sufficient safety resection margins will be important.

Intussusception due to rectal adenocarcinoma in a young adult: A case report

An intussusception due to colonic adenocarcinoma has sometimes been reported. However, to the best of our knowledge, reports of intussusception due to rectal adenocarcinoma are extremely rare. In this report, the case of a young man with rectal adenocarcinoma causing intussusception is described. A 24-year-old man visited a hospital complaining of abdominal pain, and an upper rectal cancer was diagnosed by colonoscopy. Computed tomography showed intussusception caused by a large tumor in the pelvis and absence of distant metastases. Locally advanced rectal cancer causing intussusception was diagnosed, and a low anterior resection was performed. Intraoperatively, repair of the invagination could not be accomplished easily; therefore, the repair was abandoned. Instead, the tumor was removed en bloc to avoid dissemination of the cancer. Histopathologically, the tumor was diagnosed as a poorly differentiated adenocarcinoma, pStage IIA. The patient has no evidence of recurrence at 10 mo after the operation.

Effectiveness of circumferential endoscopic mucosal resection with a novel tissue-anchoring device

AIM: To evaluate the efficacy of circumferential endoscopic mucosal resection (EMR) with a tissue-anchoring device in comparison to forceps precut EMR and conventional endoscopic submucosal dissection (ESD).

METHODS: The study was designed as a prospective, randomized, ex vivo study. Fresh ex vivo specimens were harvested from adult white Yorkshire pigs weighing 30-50 kg. Seventy-five standardized, artificial lesions measuring 3 cm × 3 cm were created by methylene blue tattoo at the greater curvature in fresh ex vivo stomachs using the EASIE-R simulator platform (Endosim LLC, Berlin, MA, United States). The three advanced endoscopists performed the three resection techniques such as circumferential EMR using the tissue-anchoring device (TA-EMR), forceps precut EMR (FP-EMR), and endoscopic submucosal dissection. The endoscopists and the type of cutting methods were determined randomly by grouped randomized selection. The resection bed was grossly inspected to determine whether the lesion was resected “en-bloc” (defined as no remaining mucosal tattoo remaining on specimen). The resection bed was also probed for evidence of perforation. The procedural time of circumferential resection, submucosal dissection, and injection frequency were recorded by an independent observer.

RESULTS: All 75 created lesions were successfully resected by three advanced endoscopists using the three techniques. The mean ± SD size of resected specimens (long axis) were 39.5 ± 5.6 mm, 36.5 ± 7.3 mm, and 44.6 ± 5.6 mm for TA-EMR, FP-EMR, and ESD respectively. The overall mean dissection time of both the TA-EMR and FP-EMR was significant shorter than ESD (TA-EMR: 5.1 ± 3.3 min, FP-EMR: 3.5 ± 2.0 min vs ESD: 15.8 ± 9.5 min, P < 0.001, P < 0.001). The overall mean total procedure time of both the tissue-anchoring and forceps circumferential EMR was significantly shorter than ESD (TA-EMR: 17.5 ± 6.0 min, FP-EMR: 16.6 ± 6.6 min vs ESD: 28.6 ± 13.9 min, P < 0.001, P < 0.001). The en-bloc resection rate of ESD was 100% (25/25) and the en-bloc resection rate of the TA-EMR (84.0%, 21/25) was higher than for the FP-EMR (60.0%, 15/25), yet not statistically significant (P = 0.18). The perforation rate of each technique was 8.0% (2/25).

CONCLUSION: TA-EMR appears to be quicker than ESD, and there was a trend towards improved en bloc resection rate with the TA-EMR when compared to the FP-EMR.

Endoscopic en bloc resection of an exophytic gastrointestinal stromal tumor with suction excavation technique

Here, we report the first successful endoscopic resection of an exophytic gastrointestinal stromal tumor (GIST) using a novel perforation-free suction excavation technique. A 49-year-old woman presented for further management of a gastric subepithelial tumor on the lesser curvature of the lower body, originally detected via routine upper gastrointestinal endoscopy. Abdominal computed tomography and endoscopic ultrasound showed a 4-cm extraluminally protruding mass originating from the muscularis propria layer. The patient firmly refused surgical resection owing to potential cardiac problems, and informed consent was obtained for endoscopic removal. Careful dissection and suction of the tumor was repeated until successful extraction was achieved without serosal injury. We named this procedure the suction excavation technique. The tumor’s dimensions were 3.5 cm × 2.8 cm × 2.5 cm. The tumor was positive for C-KIT and CD34 by immunohistochemical staining. The mitotic count was 6/50 high-power fields. The patient was followed for 5 years without tumor recurrence. This case demonstrated the use of endoscopic resection of an exophytic GIST using the suction excavation technique as a potential therapy without surgical resection.

Rare primary rectal mucosa-associated lymphoid tissue lymphoma with curative resection by endoscopic submucosal dissection: A case report and review of literature

BACKGROUND

Extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma) occurs in approximately 9% of non-Hodgkin B-cell lymphomas. The gastrointestinal tract is the most commonly affected site of the extranodal forms of primary non-Hodgkin’s lymphomas. However, it rarely occurs within the rectum, and at present, there is no consensus on its diagnosis and treatment at this site.

CASE SUMMARY

We report a rare laterally spreading tumour-like rectal MALT lymphoma case in which the diagnosis and the depth of infiltration were determined by magnifying endoscopy and ultrasonic endoscopy. Then, the lesion was en bloc resected by endoscopic submucosal dissection (ESD) alone. The lesion was confirmed as MALT lymphoma by haematoxylin and eosin staining, immunohistochemical staining and gene arrangement analysis. Surveillance exams have indicated a 2-year disease-free survival for this patient.

CONCLUSION

We report a rare primary rectal MALT lymphoma that was curable with resection by ESD. ESD is a safe and effective therapeutic option for rectal MALT lymphoma.

Rare anaplastic sarcoma of the kidney: A case report

BACKGROUND

Anaplastic sarcoma of the kidney (ASK) is a rare and newly recognized renal neoplasm. The tumor usually is extensive and cystic, characterized by pleomorphic spindle cells with marked atypia and associated with multinucleated cells. To date, only 27 cases have been reported in the literature. The authors present an additional case and summarize the relevant knowledge in the literature.

CASE SUMMARY

A 27-year-old previously healthy woman presented with a palpable mass over the abdomen and right flank soreness for one year. After the computed tomography study, the patient underwent right radical nephrectomy obtaining a 1680-g tumor with a size of 18.4 cm × 14.5 cm × 11 cm. The tumor is chiefly composed of anaplastic spindle cells with marked nuclear atypia admixed with multinucleated cells. Immunohistochemical evaluation of tumor cells exhibited diffuse positivity for CD56, p53, and vimentin, and focally positive for desmin. The diagnosis of ASK was established. Unfortunately, a local tumor recurrence followed by a distant metastasis developed within months. The patient died 26 months after the initial surgery. Comparing to the previously 27 cases of ASK, the current case had a relatively worse prognosis, which might be potentially associated with older patient age, larger tumor size, and the lack of en-bloc resection of adjacent organs during the initial radical nephrectomy.

CONCLUSION

This case points out the featured pathological findings for diagnosing ASK and suggests more aggressive management for patients with ASK.