Ex vivo comparison study of smart Shooter®, a new endoscopic device for safe and speedy treatment

Long-term outcome of cervical lymph node metastasis in superficial pharyngeal squamous cell carcinoma after endoscopic submucosal dissection

BACKGROUND AND AIMS

Superficial pharyngeal squamous cell carcinoma (PSCC) has received increasing attention as a therapeutic target in the GI field with recent innovations in endoscopic submucosal dissection (ESD). However, there are currently no defined criteria for the application of ESD to superficial PSCC. One of the problems encountered during follow-up after ESD is cervical lymph node metastasis (LNM). Identifying the clinicopathologic predictors of cervical LNM can help to provide a basis for the refinement of therapeutic strategies for superficial PSCC.

METHODS

The risk of cervical LNM was evaluated in 331 patients with superficial PSCC who underwent initial ESD between 2008 and 2021. Since tumor size, rather than depth, is the dominant factor in the current TNM classification for PSCC, the correlation between tumor size and thickness was investigated.

RESULTS

The median follow-up period was 4.8 years. The cumulative 5-year cervical LNM rate was 6.1%. Multivariate Cox proportional hazards regression analysis identified tumor thickness ≥1000 μm and lymphatic invasion as significant independent predictors. Among 204 cases with subepithelial invasion, both factors were also revealed to be significant independent predictors, suggesting that tumor thickness was superior to tumor size in predicting cervical LNM. Despite the positive correlation between tumor thickness and size, there was noticeable variability in the values (R = .20), and the current staging was inadequate to identify groups at high risk for cervical LNM.

CONCLUSIONS

Tumor thickness and lymphatic invasion are validated as significant independent predictors for cervical LNM and can be useful indicators to optimize the therapeutic strategies for superficial PSCC.

Usefulness of "Nelaton Attachment" for endoscopic submucosal dissection of colorectal neoplasms

Background and study aims  Although colorectal endoscopic submucosal dissection (ESD) has enabled high en bloc resection rates regardless of tumor size, colorectal ESD is still a challenging procedure. We developed a novel device called the Nelaton Attachment, which allows endoscopists to manipulate the ESD knives using two fingers of their left hand while holding the endoscope with their right hand. We retrospectively investigated the efficacy and safety of the Nelaton Attachment for colorectal ESD. We compared efficacy and safety between Nelaton Attachment and non-Nelaton Attachment groups, and also conducted an ex vivo experiment to evaluate the effect of the Nelaton Attachment. Patients and methods  We retrospectively reviewed 36 consecutive patients with 37 colorectal tumors who had undergone ESD at Kishiwada Tokushukai Hospital and Naritatomisato Tokushukai Hospital between April 2016 and September 2018. The Nelaton Attachment was used for 22 of the 37 colorectal ESDs. In the ex vivo experiment, endoscopists inserted and withdrew an ESD knife 2 cm using two fingers of their left hand with and without the Nelaton Attachment. Results  Median procedure time was significantly shorter in the Nelaton Attachment group (38 min [range 6 - 195 min]) compared to the non-Nelaton Attachment group (75 min [range 17 - 198 min]; P  = 0.030). Median time to complete the ex vivo experiment five times was significantly faster with the Nelaton Attachment than without the Nelaton Attachment ( P  = 0.001). Conclusions  Use of the Nelaton Attachment for colorectal ESD is feasible and safe, and may facilitate colorectal ESD procedures.