Effects on anorectal function of endoscopic submucosal dissection for rectal tumors involving the dentate line.

OBJECTIVE: Endoscopic submucosal dissection (ESD) is a specific procedure that uses an electrosurgical knife for en-bloc resectioning large tumors. However, no study has examined the effect of ESD on the defecation function of patients with rectal tumors. We aimed to investigate the potential effects caused by ESD by analyzing changes in the morphology and movement of the anorectum pre- and post-ESD. METHODS: This prospective observational study included 11 patients with anorectal tumors who underwent ESD between April 2020 and February 2022. Pre-ESD assessments included anorectal manometry and defecography. Post-ESD assessments were conducted 2 months later, including anorectal manometry, defecography, and proctoscopy for ulcer and stenosis evaluation. RESULTS: The median patient age was 73 years, including seven males and four females. Eight patients (73%) had a tumor in the lower rectum, and the extent of resection was less than 50% of the rectal lumen. Resection reached the dentate line in six cases (55%). In the patients with post-ESD mucosal defects involving the dentate line, the median of functional anal canal length significantly decreased from (3.4 cm pre-ESD to 2.8 cm post-ESD, p = 0.04). Defecography revealed one case with incomplete evacuation (<50%) and incontinence post-ESD. Interestingly, patients with pre-existing rectoceles noted resolution of lesions post-ESD. None of the patients reported daily constipation or fecal incontinence. CONCLUSIONS: While rectal ESD is unlikely to cause significant real-world defecation difficulties, alterations in rectal and anal canal morphology and function may occur if the dentate line is involved in the resection range.

Risk factors for adverse events associated with endoscopic submucosal dissection for superficial pharyngeal cancer.

BACKGROUND: Superficial pharyngeal cancer can be treated with curative intent while preserving function using minimally invasive peroral endoscopic resection techniques such as endoscopic submucosal dissection (ESD). However, severe adverse events occasionally occur, such as laryngeal edema requiring temporary tracheotomy and fistula formation. Therefore, we investigated the risk factors for adverse events associated with ESD for superficial pharyngeal cancer. METHODS: This retrospective observational study was conducted at a single institution, and 63 patients who underwent ESD were enrolled. The primary outcome was the risk factors for adverse events associated with ESD. The secondary outcomes were adverse events associated with ESD and their frequency. RESULTS: The overall adverse event rate was 15.9% (10/63). The incidence of laryngeal edema requiring prophylactic temporary tracheotomy was 11.1%, while laryngeal edema requiring emergency temporary tracheotomy, postoperative bleeding, aspiration pneumonia, fistula, abscess, and stricture formation occurred in 1.6% of patients, respectively. Logistic regression analyses showed that a history of radiotherapy for head and neck cancer was a risk factor for adverse events (odds ratio [OR], 16.67; 95% confidence interval [CI], 3.04-91.34; p = 0.001). After adjusting the model for differences in the baseline risk factors using the inverse probability of treatment weighting method, the adverse events were found to increase in association with a history of radiotherapy for head and neck cancer (OR, 39.66; 95% CI,5.85-268.72; p < 0.001). CONCLUSION: History of radiotherapy for head and neck cancer is an independent risk factor for adverse events associated with ESD for superficial pharyngeal cancer. Among adverse events, laryngeal edema requiring prophylactic temporary tracheotomy was particularly high.

Lymph Node Metastasis of Mixed Adenoneuroendocrine Carcinoma after Curative Resection Using the Expanded Criteria for Early Gastric Cancer.

Endoscopic submucosal dissection (ESD) of lesions using expanded indications for early gastric cancer (EGC) has been accepted as an alternative treatment for cases without lymph node metastasis. We herein report a rare case of metastatic lymph node tissue in mixed adenoneuroendocrine carcinoma (MANEC) after curative ESD using the expanded pathological criteria. A 70-year-old man underwent ESD for two EGC lesions. A pathological examination revealed lesions that required curative resection based on the expanded pathological criteria of the Japanese classification of gastric carcinoma. However, lymph node metastasis was detected at 26 months after ESD. Additional surgical resection was performed and MANEC was pathologically diagnosed in the metastatic lymph node. The patient subsequently underwent additional chemotherapy and remains alive at 2 years after surgery. Even though MANEC is a rare tumor, this case suggests that periodic follow-up is important when patients undergo curative resection by ESD based on the expanded indications because of the high malignant potential and the poor prognosis.