Introduction

Endoscopic submucosal dissection (ESD) for superficial pharyngeal cancer has been developed and accepted among endoscopists in Japan. Compared with surgical resection, this procedure is less invasive, but it is considered relatively difficult because of the poor maneuverability of the endoscope as a result of a narrow working space. And a lack of anatomical knowledge can cause complications that are not experienced with gastrointestinal ESD. In the subepithelial layer of the pharyngeal region, the superior laryngeal nerve is a branch of the vagus nerve. The nerve consists of two branches, one of which is the internal laryngeal nerve that supplies sensory fibers to the laryngeal mucosa. Damage to this nerve may result in postoperative dysphagia and hoarseness due to laryngeal hyposensitivity.

Aims & Methods

The present study aimed to investigate the method and significance of preserving the superior laryngeal nerve during ESD for superficial pharyngeal cancers.
We retrospectively analyzed 65 consecutive superficial pharyngeal cancers of 50 patients who were treated with ESD between February 2015 and February 2023. Of these, the clinicopathological characteristics and treatment outcomes of lesions in which the superior laryngeal nerve could be recognized during ESD were analyzed.

Results

The nerves were recognized in 32 lesions, of which 7 lesions (22%) were in the nerve damaged group. Univariate analysis revealed that there were no significant differences in the mean age, sex ratio, median tumor size, mean resection time, en bloc resection rate, or R0 resection rate in two groups. However, we had two complicated cases on the nerve damaged group, included severe subcutaneous emphysema and prolonged dysphagia. Therefore, we have developed a strategy for preserving the internal laryngeal nerve during pharyngeal ESD. We performed a circumferential incision using a dual knife (KD-650Q; Olympus Medical Systems, Tokyo, Japan) from the edge of the aryepiglottic fold. We carefully made a shallow incision to avoid damaging the nerve at the tip of the piriform sinus. After exposing the nerve, we fully injected and continued to dissect the adequate layer while using the preserved nerve as a landmark.

Conclusion

We need to minimize excessive resection and contributed to reduce unnecessary damage to the deeper structures such as nerves and muscles. Distinctive anatomical knowledge and treatment strategies are essential to prevent postoperative complications.

References

1 Iizuka T, Kikuchi D, Suzuki Y, et al. Clinical relevance of endoscopic treatment for superficial pharyngeal cancer: feasibility of techniques corresponding to each location and long-term outcomes. Gastrointest Endosc 2021; 93: 818–827
2 Iizuka T, Kikuchi D, Hoteya S, et al. Clinical advantage of endoscopic submucosal dissection over endoscopic mucosal resection for early mesopharyngeal and hypopharyngeal cancers. Endoscopy 2011; 43: 839–843
3 Kitagawa J, Shingai T, Takahashi Y et al. The pharyngeal branch of the glossopharyngeal nerve plays a major role in reflex swallowing of the pharynx. Am J Physiol Regul Comp Physiol 2002; 282: R1342–R1347
4 Tateya I, Morita S, Ishikawa S et al. Voice outcomes in patients treated with endoscopic laryngopharyngeal surgery for superficial hypopharyngeal cancer. Clin Exp Otorhinolaryngol 2016; 9: 70–74
5 Park YM, Kim WS, De Virgilio A, et al. Transoral robotic surgery for hypopharyngeal squamous cell carcinoma: A 3-year oncologic and functional analysis. Oral Oncol 2012; 48: 560–566

Introduction

Endoscopic submucosal dissection (ESD) is a challenging procedure for treating superficial pharyngeal cancer (SPC). While previous studies have utilized conventional endoscopes (CE), recent advancements in endoscopic equipment have made it possible to use ultra-thin endoscopes (UTE) for ESD. The purpose of this study was to evaluate the impact of using UTE on ESD for SPC.

Aims & Methods

A total of 97 lesions in 81 patients who underwent ESD for SPC between January 2021 and March 2023 were retrospectively analyzed. Patients who underwent ESD using UTE (1200N: Olympus, Tokyo Japan) were classified into the UESD group, while those who underwent ESD using CE (Q260J: Olympus, Tokyo Japan) were classified into the CESD group.

Results

Of the 81 patients, 24 underwent UESD for 30 lesions, while 57 underwent CESD for 67 lesions. In the UESD group, the mean age was 70 years, with 20 males and 4 females. The mean maximum lesion size and resection specimen size were 17.7 mm and 28.5 mm, respectively. The histologic depth was CIS/SEP 17/13. The average dissection time was 41.6 minutes, and the volume of local injection (glyceol) used was 4.2 ml. Traction was used in 28 cases. In the CESD group, the mean age was 70 years, with 52 males and 5 females. The mean maximum lesion size and resected specimen size were 18.4 mm and 29.2mm, respectively. The histologic CIS/SEP was 24/43. The mean dissection time was 32.3 minutes (p=0.099), and the volume of local injection used was 7.1 ml (p=0.002). Traction was used in all cases. Both groups had a 100% en bloc resection rate and zero treatment-related complications.

Conclusion

The use of UTE in ESD for SPC is a safe alternative to CE. The use of UTE resulted in a reduction in the amount of local injection required, and in some cases, traction was not necessary. However, the dissection time tended to be longer. From the surgeon's perspective, UTE made it easier to access the subepithelial layer and secure the dissected layer, with less interference from other devices, resulting in reduced stress during the procedure.

Clinical Case Summary

A 65-year old man visited our hospital for abdominal pain. Esophagogastroduodenoscopy showed an area of fainted redness in the right upper thoracic esophagus. Narrow band imaging (NBI) detected a demarcated area with brownish dots. Intrapapillary capillary loops (IPCL) implied that the carcinoma had not invaded the deep submucosa. The entire lesion showed no stains by 1% Lugol’s iodine solution. Therefore, endoscopic submucosal dissection (ESD) was conducted under general anesthesia with endotracheal intubation. Labeling, submucosal injection, mucosal incision were performed according to surgical protocols. During dissection, however, a depression was observed in the left of the cancer lesion. Submucosal and muscular defects appeared in the depression edge, which indicated a shallow pulsion diverticulum under the lesion. We proceeded cautiously the dissection to separate the submucosa from the adventitia. ESD was successfully completed without perforation. To prevent postoperative perforation, we placed a covered esophageal stent. Post-ESD CT showed mild mediastinal emphysema. No other adverse events were observed and the patient was discharged at five days after ESD. The esophageal stent was removed at one month after ESD without perforation, stenosis or bleeding. Histopathological examination showed a well-differentiated squamous cell carcinoma within the mucosa without lympho-vascular invasion, suggesting a low risk of recurrence without additional treatment. Esophageal cancer that involves diverticula is extremely rare. The thin wall of diverticulum is easily to be perforated, bringing a great challenge to endoscopic resection. The location of an esophageal diverticulum in the cancer lesion is critical to its outcome.In conclusion, we reported a rare case of a superficial esophageal cancer with an esophageal diverticulum, which was invisible before the ESD. The cancer was successfully removed by ESD with no perforation.

References

1. Watanabe S, Matsuda, K. Arima K, et.al. Detection of subclinical disorders of the hypopharynx and larynx by gastrointestinal endoscopy. Endoscopy. 1996; 28(3): 295-298.
2. Herbella, Fernando A M et al. Are idiopathic and Chagasic achalasia two different diseases? Digestive diseases and sciences vol. 49,3 (2004): 353-60.
3. Shinwa, T, Takashi T, Yoshiko O, et al. Esophageal diverticulum exposed during endoscopic submucosal dissection of superficial cancer. World J Gastroenterol. 2015 March 14;21(10):3121-3126.

Disclosure

All authors declare that there is no conflict of interest.

Introduction

Endoscopic submucosal dissection (ESD) has become a common treatment method for superficial esophageal cancer, allowing complete resection and accurate postoperative pathological evaluation, especially for relatively larger lesions^{1, 2}. However, resection of larger lesions, especially circumferential lesions, can be time-consuming and challenging. The resected tissue can obstruct the esophageal lumen, leading to limited working space and poor visibility, thereby increasing the risk of adverse events such as perforation and muscular injury³. In recent years, several auxiliary traction techniques have been emerged, including positional adjustment traction, hemostatic clip elastic band traction, snare traction, line traction, and magnet anchor traction, which significantly improve the visibility of the submucosal layer during dissection and enhance the efficiency of the procedure ^4-5. Among these techniques, snare traction allows bidirectional traction through "push and pull" maneuvers, offering flexibility and practicality in clinical practice. However, due to the difficulty and limited cases of circumferential esophageal ESD, there is currently no published literature demonstrating the advantages of snare traction-assisted ESD over traditional ESD techniques.

Aims & Methods

This study aims to investigate the efficacy and safety of snare traction assisted ESD for the management of circumferential superficial esophageal cancer. A total of 68 patients who underwent ESD for circumferential superficial esophageal cancer were included in this study. All the patients were divided into two groups based on whether the snare traction was used or not; the snare traction group (S-ESD, group n=35) and the control group (C-ESD, group n=33).

Results

There was no significant difference in the size of the resected area between the groups [21.98 (18.30, 27.00) cm² vs 24.00 (15.28, 30.72) cm², P=0.976]. The snare traction group had a shorter dissection time [92.00 (74.00, 121.00) min vs 110.00 (92.50, 137.00) min, P=0.017] and a faster resection speed [0.28±0.13 cm²/min vs 0.22±0.11cm²/min, P=0.040] compared to the control group. There were no statistically significant differences between the two groups in terms of hospital stay, cost, en bloc resection rate, R0 resection rate, curative resection rate，bleeding rate, perforation rate, stricture rate, and recurrence rate (P>0.05).

Conclusion

Snare traction-assisted ESD is a safe and efficient approach for the treatment of circumferential superficial esophageal cancer. Its advantages includes shorter procedure so the anesthesia requirement, clear operative filed view, improved mucosal dissection efficiency, simple, and easily accessible equipment.

References

1 Ishihara R, Arima M, Iizuka T et al. Endoscopic submucosal dissection/endoscopic mucosal resection guidelines for esophageal cancer. Dig Endosc. 2020; 32: 452-93.
2 Draganov PV, Wang AY, Othman MO, Fukami N. Aga institute clinical practice update: Endoscopic submucosal dissection in the united states. Clin Gastroenterol Hepatol. 2019; 17: 16-25.e1.
3 Zhang W, Zhai Y, Chai N et al. Endoscopic submucosal tunnel dissection and endoscopic submucosal dissection for large superficial esophageal squamous cell neoplasm: Efficacy and safety study to guide future practice. Surg Endosc. 2018; 32: 2814-21.
4 Fukami N. What we want for esd is a second hand! Traction method. Gastrointest Endosc. 2013; 78: 274-6.
5 Jin P, Yu Y, Fu KI, Yu DL, Li AQ, Sheng JQ. A new traction method with use of the snare as a "second hand" during endoscopic submucosal dissection. Endoscopy 2015; 47 Suppl 1 UCTN: E286-7.

Introduction

There has been a rise in the uptake of endoscopic submucosal dissection (ESD) for superficial pharyngeal cancers, including in patients with previous history of radiotherapy, whether as salvage treatment of residual lesions or for metachronous lesions inside the irradiated field. Previous studies have demonstrated the safety and effectiveness of ESD for pharyngeal cancers¹. However, the safety and the effectiveness of pharyngeal ESD in cases with previous history of radiotherapy is not clear^2,3.

Aims & Methods

Our aim was to investigate whether radiotherapy affects outcomes after pharyngeal ESD. We conducted a retrospective cohort study of consecutive patients who underwent pharyngeal ESD between December 2016 and February 2025 at our institution. All the cases were managed together with otolaryngologists, including the daily assessment of the wound and swallowing function with the transnasal flexible laryngoscope in order to decide the timing of the re-initiation of food after ESD. The ESD itself, as well as the short and long-term outcomes were compared between the patients with or without history of radiotherapy.

Results

There were 22 cases (25 lesions) of ESD performed with previous history of radiotherapy and 32 cases (33 lesions) without prior radiotherapy. The median age was 71 (range 55-85) and 98.3% were men. Radiotherapy dose ranged from 54 to 70 Gy. There were no significant differences in the baseline characteristics between the groups of patients with or without prior radiotherapy including the age, sex, or the proportion of patients with previous history of pharyngeal ESD. En-bloc resection was achieved in all cases. ESD in the pharynx post-radiotherapy was associated with an increased percentage of cases with severe fibrosis (41% vs. 14% p<0.05), and the speed of dissection was slower (33.4mm²/min vs. 45.8mm²/min p=0.03), but there were no significant differences in the short-term outcomes between the groups of patients with or without prior radiotherapy in terms of of bleeding (0% vs. 3%), aspiration pneumonia (8% vs. 9%), the duration to the resumption of food (median 4 vs. 5 days) or hospital stay (median 9 vs. 9 days). During a median follow-up period of 906.5 days (range 22-3021 days), the 3-year overall survival rate was lower in patients with previous history of radiotherapy compared to patients without prior radiotherapy (55.1% vs. 100%, p=0.000177). Of the patients with previous history of radiotherapy, one patient died from metastatic recurrence of pharyngeal cancer, but the other five deaths were not directly associated with pharyngeal cancer (1=acute cardiac death, 1=unknown cause but unrelated to pharyngeal cancer, 1=lung cancer, 1=mantle cell lymphoma, 1=sinonasal neuroendocrine cancer) . There were no significant differences in the 3-year recurrence-free survival and the 3-year disease-related survival rates between the patients with and without prior history of radiotherapy (92.9% vs. 91.7% and 92.3% vs. 100%, respectively).

Conclusion

Previous history of radiotherapy increases the risk of severe fibrosis during ESD and is associated with slower speed of dissection, but does not compromise the safety or the swallowing function. In the long-term, ESD is an effective method for the treatment of superficial pharyngeal cancers, including in patients with previous history of radiotherapy. Furthermore, ESD is a minimally-invasive and surgery-sparing treatment option, which may be all the more important in patients with prior history of radiotherapy, given the worse prognosis from illnesses other than pharyngeal cancers in this group of patients.

References

1. Watanabe A, Taniguchi M, Kimura Y, Hosokawa M, Ito S, Tsukamoto S, Sasaki S. Synopsis of transoral endoscopic laryngopharyngeal surgery for superficial pharyngeal cancers. Head Neck. 2017 Sep;39(9):1779-1787.
2. Yoshida T, Shimizu Y, Ono S, Oridate N, Kato M, Asaka M. Successful salvage endoscopic mucosal resection for residual superficial hypopharyngeal carcinoma after chemoradiotherapy, with long-term survival. Endoscopy. 2009 Jun;41(6):568-9.
3. Satake H, Yano T, Yoda Y, Fujii S, Zenda S, Tomioka T, Shinozaki T, Miyazaki M, Kaneko K, Hayashi R. Feasibility of salvage endoscopic resection for patients with locoregional failure after definitive radiotherapy for pharyngeal cancer. Endosc Int Open. 2015 Aug;3(4):E274-80.

Introduction

Gastric endoscopic submucosal dissection (ESD) has become increasingly popular worldwide as a less invasive curative treatment for early gastric cancer. However, ESD requires highly endoscopic technical skills, and it is important for trainees to develop effective training methods for ESD. ESD training is generally conducted using extracted porcine digestive tracts, but there are several issues regarding ethics, costs, infection, and logistics. In collaboration with KOTOBUKI Medical, we have developed the G-Master, a training model that can simulate ESD in several locations in the stomach. Since G-Master uses plant-derived mucous membrane sheet, there is no contamination and training can be easily performed using endoscope units and devices that are commonly used in clinical practice. Although the G-Master has enabled pre-training before actual ESD at facilities that have adopted it, it is unclear whether it contributes to the improvement of endoscopic technical skills of trainees. In this study, we clarified the usefulness of the G-Master training for inexperienced ESD trainees.

Aims & Methods

The ESD data were collected for the first through fifth gastric ESD cases performed from March 2018 through February 2022 by 15 ESD-inexperienced endoscopists at five participating centers. The ESD data were divided into two groups, one with G-Master training and one without G-Master training and the endpoints were compared retrospectively. The endpoints were procedure speed, perforation rate, operator changing rate, and en bloc resection rate, endoscopists experiences, and clinicopathological features. The resection speed was calculated as the resected area of the specimen divided by the procedure time (mm2/min). The group with G-Master training was defined as the group of trainees who always had at least one ESD training session with G-Master before each ESD. The group without G-Master training was defined as the group of trainees who had never done G-Master ESD training.

Results

A total of 75 gastric ESD cases were enrolled, with 25 cases in the group with G-Master training performed by 5 ESD-inexperienced endoscopists and 50 cases in the group without G-Master training performed by 10 ESD-inexperienced endoscopists. There was no difference between the two groups in endoscopists experiences including the years after graduation from medical school, the number of esophagogastroduodenoscopies and colonoscopies performed, and clinical features of gastric ESD cases including the location or size. In the group with G-Master training, the median procedure speed for all cases was significantly faster (with vs without G-Master: 13.1 mm2/min vs. 8.1 mm2/min, p>0.001). And the procedure speed of the training group was linearly improved from the initial to the last cases (with vs without G-Master: initial case; 11.8 mm2/min vs 8.5 mm2/min, last case; 23.1 mm2/min vs 12.0 mm2/min). Additionally, the rates of perforation (0 case (0%) vs 1 case (2%)) and operator change to expert (5 cases (20%) vs 15 cases (30%)) were lower. There was no difference in en bloc resection rate between the two groups.

Conclusion

It was suggested that performing G-Master training before actual ESD could improve the endoscopic technical skills of trainees who are inexperienced in ESD.