Clinicopathologic characteristics and survival of patients with clinical Stage I squamous cell carcinomas of the thoracic esophagus treated with three-field lymph node dissection

Definitive-dose adjuvant radiotherapy following endoscopic submucosal dissection for superficial esophageal cancer

BACKGROUND

Prophylactic chemoradiation therapy (CRT) using 40-41.4 Gy post-endoscopic submucosal dissection (ESD) for clinical T1N0M0 esophageal cancer reportedly yields favorable outcomes. However, it cannot completely prevent locoregional lymph node (LN) metastases. We retrospectively analyzed outcomes and adverse events associated with our dose-escalated treatment regimen (definitive-dose radiotherapy [RT] of 50-61.2 Gy, with/without chemotherapy) for these patients, and predictors of progression-free survival (PFS) and overall survival (OS).

METHODS

Between 2006 and 2018, 44 consecutive patients (42 men and 2 women; median age, 70 years) who underwent definitive-dose RT post-ESD and had a pathological depth of the muscularis mucosa with lymphovascular invasion (LVI) or the upper-middle submucosal third at our institution were included. We excluded patients who could not obtain a margin-free resection by ESD. If feasible, systemic chemotherapy with 5-fluorouracil plus high- or low-dose cisplatin or nedaplatin was administered concurrently.

RESULTS

Five-year PFS, OS, and disease-specific survival rates were 78.8%, 88.4%, and 97.7%, respectively. Six metachronous esophagus (14%), two locoregional LN within the irradiated area with a prophylactic dose of 41.4 Gy (5%), and two locoregional LN plus liver (5%) recurrences occurred. No LN recurrence occurred within the definitive dose of ≥ 50 Gy in the irradiated area. Metachronous esophageal recurrence involved areas receiving ≥ 50 Gy. Univariate and multivariate analyses revealed that age was an independent prognostic factor for both PFS and OS.

CONCLUSIONS

Definitive-dose RT/CRT post-ESD could provide favorable locoregional LN control and PFS/OS regardless of patient characteristics, including pathological findings and chemotherapy regimen/course, except for age. These results need to be interpreted carefully given several limitations, therefore, definitive-dose RT/CRT should be conducted with caution in clinical practice until high-quality prospective clinical trials evaluating the effectiveness and safety.

Long-term outcomes of endoscopic resection of superficial esophageal squamous cell carcinoma in late-elderly patients

BACKGROUND AND AIM

As the population ages, the number of elderly patients with superficial esophageal squamous cell carcinoma (ESCC) is increasing. We aimed to clarify the indications for endoscopic resection (ER) in late-elderly patients with ESCC in terms of life expectancy.

METHODS

Patients aged ≥75 years who underwent ER for ESCC at our institution from January 2005 to December 2018 were enrolled. Clinical data, including the Eastern Cooperative Oncology Group performance status, American Society of Anesthesiologists physical status (ASA-PS), Charlson comorbidity index, and prognostic nutritional index (PNI), were collected at the time of ER. The main outcome measure was overall survival (OS).

RESULTS

Two hundred eight consecutive patients were enrolled. The patients' median age was 78 years (range, 75-89 years). The 5-year follow-up rate was 88.5% (median follow-up period, 6.6 years). The 5-year OS rate was 79.2% (95% confidence interval [CI], 72.2-84.8), and 5-year net survival standardized for age, sex, and calendar year was 1.04 (95% CI, 0.98-1.09). In the multivariate analysis, an ASA-PS of 3 (hazard ratio, 2.45; 95% CI, 1.16-5.17) and PNI of <44.0 (hazard ratio, 2.73; 95% CI, 1.38-5.40) were independent prognostic factors. When neither of these factors was met, the 5-year OS rate was 87.8% (95% CI, 80.0-92.9), and 5-year net survival was 1.08 (95% CI, 1.02-1.14).

CONCLUSIONS

ER for ESCC in late-elderly patients may improve life expectancy. ER is recommended in patients with a good ASA-PS and PNI.

Treatment strategy for early-stage esophageal cancer

Approximately 90% of esophageal cancers in Japan are squamous cell carcinomas, and they are often detected at earlier stages in Japan than in Western countries; superficial esophageal cancer without lymph node or distant metastasis comprises one-third of all esophageal cancers in Japan. Endoscopic resection is a minimally invasive treatment for superficial esophageal cancer; however, the risk of regional lymph node recurrence is negligible when it invades the submucosal layer or lymphovasculature. In such cases, surgical treatment is necessary to control regional lymph node recurrences, although the physical burdens and potential complications cannot be overlooked. Recently, clinical trials in Japan have shown promising clinical outcomes of organ preservation strategies. One strategy is initially performing endoscopic resection for superficial esophageal cancer, assessing the risk of lymph node metastasis based on pathological diagnosis for endoscopically resected specimens, and subsequently considering additional therapy (e.g., observation or prophylactic chemoradiotherapy)-another strategy aimed to cure superficial esophageal cancer through definitive chemoradiotherapy alone. The safety and efficacy of the two strategies have been evaluated in clinical trials, which showed that both organ preservation strategies are comparable to surgery in terms of overall survival. However, challenges include improving the accuracy of pretreatment endoscopic diagnosis and decreasing the local-regional recurrence after chemoradiotherapy. This review provides an overview of the latest standard treatment for early-stage esophageal cancer and its future perspectives.

Recent progress in chemoradiotherapy for oesophageal squamous cell carcinoma

Oesophageal squamous cell carcinoma is a common malignancy worldwide. Definitive chemoradiotherapy is the standard treatment for patients with resectable stage oesophageal squamous cell carcinoma who cannot undergo surgery, as well as those with locally advanced unresectable oesophageal squamous cell carcinoma. However, it has several disadvantages such as poor survival, radiation-related toxicities and severe and lethal complications related to salvage treatment for residual or recurrent disease. Numerous clinical trials on chemoradiotherapy have been conducted to confirm the optimal combination of irradiation and chemotherapy. For advanced disease, multimodal treatment strategies including salvage surgery are essential. Palliative chemoradiotherapy is also crucial for dysphagia in locally advanced oesophageal squamous cell carcinoma with or without metastatic lesions. Recently, the synergistic mechanism of radiotherapy combined with immunotherapy has been reported. Early phase clinical trials suggest that a combination of immunotherapy and chemoradiotherapy can improve clinical outcomes with manageable side effects, but further investigations are needed. Here, we reviewed the existing clinical data and current development of chemoradiotherapy combined with immunotherapy in patients with oesophageal squamous cell carcinoma.

Efficacy and Safety of First-line Therapies for Advanced Unresectable Oesophageal Squamous Cell Cancer: a Systematic Review and Network Meta-analysis

AIM

To compare the clinical efficacy and safety of first-line treatments for advanced unresectable oesophageal squamous cell cancer.

MATERIALS AND METHODS

A systematic review and network meta-analysis was carried out by retrieving and retaining relevant literature from databases. The studies were randomised controlled trials comparing first-line treatments for advanced unresectable oesophageal squamous cell cancer. A Bayesian network meta-analysis was used to assess clinical outcomes.

RESULTS

Nine studies including 4499 patients receiving first-line treatments were analysed. For all populations, toripalimab plus chemotherapy tended to provide the best overall survival (hazard ratio 0.58, 95% confidence intervals 0.43-0.78) and sintilimab plus chemotherapy provided the best progression-free survival (0.56, 0.46-0.68). Nivolumab plus chemotherapy presented the best objective response rate (odds ratio 2.45, 1.78-3.42) and camrelizumab plus chemotherapy (0.47, 0.29-0.74) appeared to be the safest. Sintilimab plus chemotherapy (0.55, 0.40-0.75) and nivolumab (0.54, 0.37-0.80) plus chemotherapy had the best overall survival in programmed death ligand 1 (PD-L1) tumour proportion score <1% and ≥1% subgroups. Toripalimab plus chemotherapy (0.61, 0.40-0.93) and pembrolizumab (0.57, 0.43-0.75) were the best in overall survival in combined positive score <10 and ≥10 subgroups, respectively. Toripalimab plus chemotherapy showed the best overall survival in the Asian group; pembrolizumab presented better overall survival in the Asian population than the non-Asian group.

CONCLUSION

Most immunotherapy combined with chemotherapy showed superior clinical benefits and sintilimab plus chemotherapy, toripalimab plus chemotherapy and tislelizumab plus chemotherapy had better comprehensive clinical efficacy. PD-L1 expression detection and ethnicity differences are still of great significance and most suitable regimens varied from each subgroup.

A single-center prospective study evaluating the usefulness of artificial intelligence for the diagnosis of esophageal squamous cell carcinoma in a real-time setting

BACKGROUND

Several pre-clinical studies have reported the usefulness of artificial intelligence (AI) systems in the diagnosis of esophageal squamous cell carcinoma (ESCC). We conducted this study to evaluate the usefulness of an AI system for real-time diagnosis of ESCC in a clinical setting.

METHODS

This study followed a single-center prospective single-arm non-inferiority design. Patients at high risk for ESCC were recruited and real-time diagnosis by the AI system was compared with that of endoscopists for lesions suspected to be ESCC. The primary outcomes were the diagnostic accuracy of the AI system and endoscopists. The secondary outcomes were sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and adverse events.

RESULTS

A total of 237 lesions were evaluated. The accuracy, sensitivity, and specificity of the AI system were 80.6%, 68.2%, and 83.4%, respectively. The accuracy, sensitivity, and specificity of endoscopists were 85.7%, 61.4%, and 91.2%, respectively. The difference between the accuracy of the AI system and that of the endoscopists was - 5.1%, and the lower limit of the 90% confidence interval was less than the non-inferiority margin.

CONCLUSIONS

The non-inferiority of the AI system in comparison with endoscopists in the real-time diagnosis of ESCC in a clinical setting was not proven.

TRIAL REGISTRATION

Japan Registry of Clinical Trials (jRCTs052200015, 18/05/2020).

Impact of endoscopic surveillance on mortality of metachronous esophageal and head and neck cancer after esophageal endoscopic resection

BACKGROUND AND AIM

As more superficial esophageal cancer (EC) patients are being treated with endoscopic resection (ER), it is important to understand the outcomes, including survival data, of patients who develop metachronous EC and head and neck cancer (HNC). We aimed to evaluate the long-term surveillance and survival outcomes of metachronous EC and HNC after esophageal ER.

METHODS

This study included 627 patients who underwent ER of superficial esophageal squamous cell carcinoma from 2008 to 2016 and were generally followed by annual or biannual esophagogastroduodenoscopy up to 2019 at Osaka International Cancer Institute. Data on metachronous cancer development and causes of death were collected from an integrated database of hospital-based cancer registry and Vital Statistics of Japan.

RESULTS

During a median (range) follow-up period of 67.4 (3.8-142.7) months, 230 patients (36.7%) developed 500 metachronous ECs and 126 patients (20.1%) developed 239 metachronous HNCs, post-ER of index EC. The 3-year, 5-year, and 7-year cumulative incidences were 25.8%, 36.0%, and 43.6% for metachronous EC and 10.9%, 16.0%, and 26.9% for metachronous HNC, respectively. No patients died of metachronous EC, and only seven patients (1.1%) died of metachronous HNC. The 3-year, 5-year, and 7-year disease-specific survival rates were 99.8%, 99.6%, and 98.6%, respectively.

CONCLUSIONS

The incidences of metachronous EC and HNC increase with time over 5 years after esophageal ER; therefore, surveillance endoscopy should be continued over 5 years. Endoscopic surveillance is useful for survivors after esophageal ER given the high incidence and extremely low mortality of metachronous EC and HNC.

Definitive chemoradiotherapy has comparable survival outcomes to esophagectomy in patients with clinical T1N0M0 esophageal squamous cell carcinoma: real-world data

BACKGROUND

Recently, the JCOG0502 has shown a comparable efficacy of chemoradiotherapy and esophagectomy in patients with clinical T1N0M0 esophageal squamous cell carcinoma. However, few studies have compared the clinical outcomes of these treatments in esophageal squamous cell carcinoma patients (including elderly patients) based on real-world data.

METHODS

This retrospective study determined real-world outcomes in patients who underwent chemoradiotherapy or esophagectomy, including those with clinical T1N0M0 esophageal squamous cell carcinoma, between 2009 and 2017 at the National Cancer Center Hospital East.

RESULTS

Among a total of 156 patients, 120 and 36 patients underwent esophagectomy and chemoradiotherapy, respectively; 138, 12 and 6 patients had Eastern Cooperative Oncology Group performance status 0, 1, and 2, respectively; and 33 and 123 patients had clinical tumor depth MM-SM1 and SM2-SM3, respectively. In a median follow-up of 72 months, 5-year progression-free survival and overall survival were respectively 77.0% and 81.5% in the esophagectomy group and 74.4% and 82.6% in the chemoradiotherapy group (P = 0.48 and, P = 0.89). Moreover, no treatment-related death was detected in both groups. In elderly patients (75 years or older), 5-year progression-free survival and overall survival were not significantly different between esophagectomy and chemoradiotherapy groups (5-year progression-free survival: 72.3% vs. 81.8%, P = 0.38; 5-year overall survival: 76.9% vs. 81.8%, P = 0.59).

CONCLUSIONS

This real-world study confirms the results of a previous clinical trial, and the present findings support chemoradiotherapy as one of the standard treatment options in patients of all ages with clinical T1N0M0 esophageal squamous cell carcinoma.

Positive predictive value of the clinical diagnosis of T1a-epithelial/lamina propria esophageal cancer depends on lesion size

OBJECTIVES

Endoscopic resection (ER) is a minimally invasive treatment for esophageal squamous cell carcinoma (ESCC). However, stricture may develop after ER for widespread lesions. Application of ER is justified if these cancers are pathological T1a-epithelial/lamina propria (pEP/LPM) cancers that can be cured by ER. We conducted a study to clarify the association between pathological invasion depth and lesion size or circumference in clinical (c) EP/LPM cancers.

METHODS

From our database, we identified patients diagnosed with cEP/LPM ESCC via endoscopic examination who underwent endoscopic or surgical tumor resection. The accuracy of the cEP/LPM ESCC diagnosis was determined by histologically diagnosing cancer invasion depth as a reference standard.

RESULTS

Between January 2015 and December 2019, 1271 cancer patients were diagnosed with cEP/LPM ESCC, of which 1195 (94.0%) were correctly diagnosed with pEP/LPM cancer. The positive predictive value (PPV) classified according to lesion sizes of ≤25, 26-49, and ≥50 mm was 95.8% (981/1024 lesions), 89.7% (191/213 lesions), and 67.6% (23/34 lesions), respectively. PPV according to the circumferential extent of <3/4, ≥3/4, and <1, and whole was 94.6% (1164/1230 lesions), 75.0% (24/32 lesions), and 77.8% (7/9 lesions), respectively. In multivariate analysis, the PPV of cEP/LPM ESCC was significantly associated with lesion size (P < 0.001) and male sex.

CONCLUSIONS

Between January 2015 and December 2019, 1271 cancer patients were diagnosed with cEP/LPM ESCC, of which 1195 (94.0%) were correctly diagnosed with pEP/LPM cancer. The PPV of cEP/LPM ESCC was related to lesion size. Treatment should be determined considering the high risk of cancer invasion into the muscularis mucosa or deeper in cEP/LPM cancers with a lesion size of ≥50 mm.

Endoscopic Diagnosis and Treatment of Superficial Esophageal Squamous Cell Cancer: Present Status and Future Perspectives

This review provides information regarding the preoperative examinations, indications for endoscopic resection (ER), and curability assessment in subjects with superficial esophageal squamous cell carcinoma (SCC). Narrow-band imaging (NBI) is a more sensitive modality for detecting esophageal cancer than conventional observation, and esophageal observation using NBI is thus recommended for the detection of superficial esophageal cancer. It is also important to adjust the volume of air in the esophagus during observation. Workup by non-magnifying followed by magnifying endoscopy is a common process for diagnosing the invasion depth of superficial esophageal SCCs in Japan. Endoscopic ultrasonography carries a risk of overdiagnosis, and its routine use is therefore not recommended. The Japanese endoscopic submucosal dissection/endoscopic mucosal resection guidelines for esophageal cancer considered the indications for ER based on the results of studies focusing on clinical MM/SM1 cancers, and concluded that clinical MM/SM1 carcinomas, except circumferential carcinoma, were an indication for ER. The curative effect of ER should be assessed based on histologic examination of the resected specimens. ER should be conducted based on a thorough understanding of the preoperative diagnosis, indication, curability, and additional treatment of esophageal SCC.

Parallel-Group Controlled Trial of Surgery Versus Chemoradiotherapy in Patients With Stage I Esophageal Squamous Cell Carcinoma

BACKGROUND & AIMS

Surgery is the standard of care for T1bN0M0 esophageal squamous cell carcinoma (ESCC), whereas chemoradiotherapy (CRT) is a treatment option. This trial aimed to investigate the noninferiority of CRT relative to surgery for T1bN0M0 ESCC.

METHODS

Clinical T1bN0M0 ESCC patients were eligible for enrollment in this prospective nonrandomized controlled study of surgery versus CRT. The primary endpoint was overall survival, which was determined using inverse probability weighting with propensity scoring. Surgery consisted of an esophagectomy with 2- or 3-field lymph node dissection. CRT consisted of 2 courses of 5-fluorouracil (700 mg/m²) on days 1-4 and cisplatin (70 mg/m²) on day 1 every 4 weeks with concurrent radiation (60 Gy).

RESULTS

From December 20, 2006 to February 5, 2013, a total of 368 patients were enrolled in the nonrandomized portion of the study. The patient characteristics in surgery arm and CRT arm, respectively, were as follows: median age, 62 and 65 years; proportion of males, 82.8% and 88.1%; and proportion of performance status 0, 99.5% and 98.1%. Comparisons were made using the nonrandomized groups. The 5-year overall survival rate was 86.5% in the surgery arm and 85.5% in the CRT arm (adjusted hazard ratio, 1.05; 95% confidence interval, 0.67-1.64 [<1.78]). The complete response rate in the CRT arm was 87.3% (95% confidence interval, 81.1-92.1). The 5-year progression-free survival rate was 81.7% in the surgery arm and 71.6% in the CRT arm. Treatment-related deaths occurred in 2 patients in the surgery arm and none in the CRT arm.

CONCLUSIONS

CRT is noninferior to surgery and should be considered for the treatment of T1bN0M0 ESCC.

Assessment of the Diagnostic Performance of Endoscopic Ultrasonography After Conventional Endoscopy for the Evaluation of Esophageal Squamous Cell Carcinoma Invasion Depth

IMPORTANCE

Distinguishing between mucosal and submucosal cancers is important for selecting the optimal treatment for patients with esophageal squamous cell carcinoma (ESCC); however, standard procedures for diagnosing cancer invasion depth have not yet been determined.

OBJECTIVE

To evaluate the diagnostic performance of endoscopic ultrasonography (EUS) after conventional endoscopy for the evaluation of ESCC invasion depth.

DESIGN, SETTING, AND PARTICIPANTS

This prospective single-arm confirmatory diagnostic study comprising 372 patients with T1 esophageal cancer was conducted at 41 secondary or tertiary hospitals in Japan. Enrollment began on July 20, 2017; patients were enrolled in 2 steps, with the first registration occurring from August 4, 2017, to December 11, 2019, and the second from August 9, 2017, to December 11, 2019. After the completion of all first and second registration examinations, patients received treatment and were followed up for 30 days, with follow-up ending on February 14, 2020. Patients were eligible for inclusion if they had pathologically or endoscopically diagnosed esophageal cancer with T1 clinical depth of invasion.

INTERVENTIONS

In the first registration, nonmagnifying endoscopy (non-ME) and magnifying endoscopy (ME) were used to diagnose cancer invasion depth. In the second registration, patients from the first registration who had cancers invading the muscularis mucosa or submucosa were enrolled and received EUS. After completion of the protocol examinations, patients received treatment with endoscopic resection or esophagectomy. The pathological results of the resected specimens were used as the reference standard for evaluating cancer invasion depth.

MAIN OUTCOMES AND MEASURES

The primary end point was the proportion of overdiagnosis of submucosal cancer (defined as invasion depth >200 μm) after receipt of non-ME and ME, with or without the addition of EUS. The secondary end points were underdiagnosis, sensitivity, and specificity.

RESULTS

Among 372 patients enrolled in the first registration, 371 received non-ME and ME. Of those, 300 patients were enrolled in the second registration, and 293 patients received EUS. A total of 269 patients (217 men [80.7%]; median age, 69 years; interquartile range, 62-75 years) were included in the final analysis. The addition of EUS was associated with a 6.6% increase in the proportion of overdiagnosis (from 16 of 74 patients [21.6%; 95% CI, 12.9%-32.7%] after non-ME and ME to 29 of 103 patients [28.2%; 95% CI, 19.7%-37.9%] after the addition of EUS; 1-sided P = .93). All subgroup analyses found similar increases in overdiagnosis of submucosal cancer. The addition of EUS was associated with a 4.5% reduction in the proportion of underdiagnosis (from 57 of 195 patients [29.2%; 95% CI, 23.0%-36.2%] after non-ME and ME to 41 of 166 patients [24.7%; 95% CI, 18.3%-32.0%] after the addition of EUS). After non-ME and ME, diagnostic sensitivity was 50.4% (95% CI, 41.0%-59.9%), specificity was 89.6% (95% CI, 83.7%-93.9%), and accuracy was 72.9% (95% CI, 67.1%-78.1%). After the addition of EUS, diagnostic sensitivity was 64.3% (95% CI, 54.9%-73.1%), specificity was 81.2% (95% CI, 74.1%-87.0%), and accuracy was 74.0% (95% CI, 68.3%-79.1%).

CONCLUSIONS AND RELEVANCE

This study found that the addition of EUS was not associated with improvements in the diagnostic accuracy of cancer invasion depth. These findings do not support the routine use of EUS after conventional endoscopy for evaluating the invasion depth among patients with T1 ESCC.

Long-term outcomes of an esophagus-preserving chemoradiotherapy strategy for patients with endoscopically unresectable stage I thoracic esophageal squamous cell carcinoma

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Endoscopically unresectable stage I esophageal cancer is usually treated by surgery.

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Operable stage I esophageal carcinomas were treated with our multimodal approach.

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Based on interim appraisal, most patients were treated with chemoradiotherapy.

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Although local recurrences were common, half of them were rescued without surgery.

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We observed favorable long-term survival and esophagus preservation rates.

Background and purpose

To assess the long-term outcomes of a multimodal approach for maximum esophagus preservation in operable patients with endoscopically unresectable stage I thoracic esophageal squamous cell carcinoma (ESCC).

Materials and methods

The medical records of patients with stage I thoracic ESCC treated with our protocol between 1992 and 2005 were retrospectively reviewed. Our protocol consisted of neoadjuvant concurrent chemoradiotherapy, followed by either additional definitive chemoradiotherapy for good responders (CRT group) or surgery for moderate or poor responders (CRT-S group) after an interim appraisal.

Results

A total of 51 patients were analysed. The median age of the patients was 67 years. The median follow-up period was 124.8 months. After the interim assessment, 49 and 2 cases were assigned to the CRT and CRT-S groups, respectively. In the intent-to-treat analyses, overall survival (OS), disease-free survival (DFS), cumulative incidence for death from esophageal cancer, and that for loss of esophageal function were 78.9%, 53.5%, 10.5%, and 20.4% at 5 years, and 55.2%, 27.8%, 18.2%, and 22.9% at 10 years, respectively. Grade 3 late toxicities occurred with the following incidences: esophageal stenosis in 1 case, esophageal ulcer in 1 case, and pericardial effusion in 2 cases. No grade 4 or higher toxicities were observed.

Conclusion

Long-term survival and esophagus preservation outcomes were favorable, with acceptable toxicities. Our results suggest that CCRT is an alternative treatment for majority of operable patients with endoscopically unresectable stage I thoracic ESCC in combination with salvage therapy.

Validity of endoscopic resection for clinically diagnosed T1a-MM/T1b-SM1 N0 M0 esophageal squamous cell carcinoma

BACKGROUND

Previous guidelines have not described clear recommendations for performing endoscopic resection (ER) of T1a-muscularis mucosa (MM)/T1b-submucosal (SM1) cancers that have invaded ≤ 200 μm because these are considered to have a non-negligible risk of metastasis based on previous analyses of pathologically diagnosed (p)MM/SM1 cancers. Considering that the indication for ER is determined based on a clinical diagnosis, the applicability of ER should be investigated in clinical (c)MM/SM1 but not pMM/SM1 cancers. This study aimed to evaluate validity of ER for cMM/SM1 cancers.

METHODS

In total, 175 cMM/SM1 esophageal squamous cell carcinoma cases that were endoscopically or surgically resected between January 2008 and December 2018 were identified from a prospectively maintained database. We histologically evaluated resected specimens and divided them into low- (n = 92) and high-risk (n = 83) cancers for metastasis.

RESULTS

Univariate analysis showed that longer tumor length and larger circumferential extent were significantly correlated with high-risk cancer (P < 0.001). Multivariate analysis showed that tumor circumference was an independent predictor of high-risk cancer (P = 0.036). The proportion of low-risk cancers among cases with ≤ 3/4, > 3/4 and < 1, and whole circumferential extent were 59, 17, and 14%, respectively, and the post-ER stricture rates of these groups were 12, 33, and 100%, respectively.

CONCLUSION

ER is the first-line treatment for cMM/SM1 cancers with ≤ 3/4 circumferential extent considering that 59% of cMM/SM1 cancers were low-risk cancers for which ER is mostly curative. ER is not recommended for whole circumferential cMM/SM1 cancers given the low proportion of low-risk cancers and the high risk of stricture after ER.

Clinical outcomes of endoscopic resection of preoperatively diagnosed non-circumferential T1a-muscularis mucosae or T1b-submucosa 1 esophageal squamous cell carcinoma

In Japan, preoperatively diagnosed T1a-muscularis mucosae or T1b-submucosa 1 (MM/SM1) esophageal squamous cell carcinoma (ESCC) is a relative indication for endoscopic resection (ER). We evaluated long-term outcomes in patients after ER for non-circumferential ESCC with a preoperative diagnosis of MM/SM1 invasion. We retrospectively reviewed 66 patients with a preoperative diagnosis of non-circumferential MM/SM1 ESCC endoscopically resected between 2010 and 2015. Patients were divided into low- (adequate follow-up) and high-risk (requiring additional treatment) groups for lymph node metastasis according to risk factors (submucosal invasion, lymphovascular invasion, or droplet infiltration) and long-term outcomes were analyzed. Pathological invasion to T1a-lamina propria mucosa, MM/SM1, and T1b-SM2 was seen in 22, 38, and 6 lesions, respectively. Overall, 71.2% patients were classified into the "adequate follow-up" group. Of these, only one patient had a lymph node recurrence, which was successfully treated by additional therapy. The remaining 28.8% patients were classified into the "requiring additional treatment" group, where no recurrences were observed after additional treatments. After a median follow-up of 58.6 months, no deaths happened due to ESCC. The 3- and 5-year overall survival rates were 93.6% and 88.7%, respectively. ER is a valid initial treatment for non-circumferential ESCC with preoperatively diagnosed MM/SM1 invasion.

Predictors of Early and Late Mortality after Endoscopic Resection for Esophageal Squamous Cell Carcinoma

In esophageal squamous cell carcinoma (ESCC) comprising 90% of cases with esophageal cancer, endoscopic resection (ER) is recommended for patients with negligible risk of ESCC-related mortality. In fact, a main cause of death in patients underwent ER is not ESCC. We thus aimed to clarify the predictors for early and late mortality among patients underwent ER of ESCC between 2005 and 2018 at our institution. In this retrospective cohort study, we investigated the prognosis and predictors of early and late mortality with the cut-off value of 3 years. We enrolled 407 patients with a median 69 months follow-up. The 5-year overall survival and disease-specific survival, an indicator of ESCC-related mortality, were 83.4% and 98.4%, respectively. In multivariate Cox analyses, Eastern Cooperative Oncology Group performance status (ECOG-PS), consisting of six grades by a patient's level of activity, ≥ 2 was a predictor for early and late morality [hazard ratio (HR), 7.21 (P = 0.007) and 15.62 (P = 0.021), respectively]. Charlson comorbidity index (CCI), which is an index for predicting mortality by comorbid conditions, ≥ 2 was also a predictor for both mortality [HR, 2.97 (P = 0.017) and 1.90 (P = 0.019), respectively]. However, age was a predictor only for late mortality [HR, 3.08 (P = 0.010) in 80-84 years and 8.38 (P < 0.001) in ≥ 85 years]. Considering the predictive ability for early mortality, we propose that ECOG-PS and/or CCI are better indices compared with age in deciding treatment strategy after ER for ESCC.

Long-term outcomes of endoscopic versus surgical resection for MM-SM1 esophageal squamous cell carcinoma using propensity score analysis

BACKGROUND

Esophageal squamous cell carcinoma (ESCC) confined to the muscularis mucosae (MM) or up to 200 µm of the submucosa (SM1) confers the risk for lymph node metastasis, and is defined as relative indication for endoscopic submucosal dissection (ESD) by the Japan Esophageal Society guidelines. Although additional surgical treatment after ESD is recommended, long-term outcomes of ESD compared with those of surgery have not been clarified. This study aimed to evaluate the long-term outcomes of ESD and surgery for cN0M0 relative indication lesions of ESCC.

METHODS

Between 2006 and 2016, patients with relative indication lesions of ESCC who underwent ESD or surgery at nine participating hospitals were examined retrospectively. Using propensity score matching, we evaluated survival curves for and hazard ratios associated with endoscopic submucosal dissection and surgery.

RESULTS

In total, 155 lesions in the ESD group and 106 lesions in the surgery group met the pathological criteria of relative indication for endoscopic resection. After matching, 50 matched pairs of patients who underwent ESD or surgery were selected. The 5-year overall survival rates were 84.5% [95% confidence interval (CI) 68-93] in the ESD group and 79% [95% CI 60-90] in the surgery group. The hazard ratio of mortality for ESD compared with that for surgery estimated by Cox regression analysis was 0.79 (95% CI 0.3-2.06, p = 0.63).

CONCLUSIONS

Compared with surgery, ESD does not compromise long-term outcomes. ESD alone or ESD with chemotherapy and/or radiotherapy may be an option for the treatment of MM and SM1 ESCC.

Artificial intelligence for cancer detection of the upper gastrointestinal tract

In recent years, artificial intelligence (AI) has been found to be useful to physicians in the field of image recognition due to three elements: deep learning (that is, CNN, convolutional neural network), a high-performance computer, and a large amount of digitized data. In the field of gastrointestinal endoscopy, Japanese endoscopists have produced the world's first achievements of CNN-based AI system for detecting gastric and esophageal cancers. This study reviews papers on CNN-based AI for gastrointestinal cancers, and discusses the future of this technology in clinical practice. Employing AI-based endoscopes would enable early cancer detection. The better diagnostic abilities of AI technology may be beneficial in early gastrointestinal cancers in which endoscopists have variable diagnostic abilities and accuracy. AI coupled with the expertise of endoscopists would increase the accuracy of endoscopic diagnosis.

Preoperative Diagnosis and Indications for Endoscopic Resection of Superficial Esophageal Squamous Cell Carcinoma

Endoscopic resection (ER) is the mainstay of treatment for superficial esophageal squamous cell carcinoma (SESCC) instead of esophagectomy because of its minimal invasiveness and favorable clinical outcomes. Developments in endoscopic submucosal dissection have enabled en bloc resection of SESCCs regardless of size, thus reducing the risk of local recurrence. Although ER for SESCC is effective, metastasis may subsequently occur. Additionally, extensive esophageal ER confers a risk of postoperative esophageal stricture. Therefore, accurate assessment of the invasion depth and circumferential extent of SESCCs is important in determining the indications for ER. Diagnostic accuracies for SESCC invasion differ between epithelial (EP)/lamina propria (LPM), muscularis mucosa (MM)/submucosal (SM1), and SM2 cancers. ER is strongly indicated for clinically diagnosed (c)EP/LPM cancers because 90% of these are as pathologically diagnosed (p)EP/LPM, which has a very low risk of metastasis. Remarkably, the diagnostic accuracy for cMM/SM1 differs significantly with lateral spread of cancer. Eighty percent of cMM/SM1 cancers with ≤3/4 circumferential spread prove to be pEP/LPM or pMM/SM1, which have very low or low risk of metastasis. Thus, these are adequate candidates for ER. However, given the relatively low proportion of pEP/LPM or pMM/SM1 and high risk of subsequent stricture, ER is not recommended for whole circumferential cMM/SM1 cancers. For cMM/SM1 cancers that involve >3/4 but not the whole circumference, ER should be considered on a lesion-by-lesion basis because the risk of post-ER stricture is not very high, but the proportion of pEP/LPM or pMM/SM1 is relatively low. ER is contraindicated for cSM2 cancers because 75% of them are pSM2, which has high risk of metastasis.

Real-time assessment of video images for esophageal squamous cell carcinoma invasion depth using artificial intelligence

BACKGROUND

Although optimal treatment of superficial esophageal squamous cell carcinoma (SCC) requires accurate evaluation of cancer invasion depth, the current process is rather subjective and may vary by observer. We, therefore, aimed to develop an AI system to calculate cancer invasion depth.

METHODS

We gathered and selected 23,977 images (6857 WLI and 17,120 NBI/BLI images) of pathologically proven superficial esophageal SCC from endoscopic videos and still images of superficial esophageal SCC taken in our facility, to use as a learning dataset. We annotated the images with information [such as magnified endoscopy (ME) or non-ME, pEP-LPM, pMM, pSM1, and pSM2-3 cancers] based on pathologic diagnosis of the resected specimens. We created a model using a convolutional neural network. Performance of the AI system was compared with that of invited experts who used the same validation video set, independent of the learning dataset.

RESULTS

Accuracy, sensitivity, and specificity with non-magnified endoscopy (ME) were 87%, 50%, and 99% for the AI system and 85%, 45%, 97% for the experts. Accuracy, sensitivity, and specificity with ME were 89%, 71%, and 95% for the AI system and 84%, 42%, 97% for the experts.

CONCLUSIONS

Most diagnostic parameters were higher when done by the AI system than by the experts. These results suggest that our AI system could potentially provide useful support during endoscopies.

Multiple gastrointestinal metastasis after endoscopic submucosal dissection for poorly differentiated gastric adenocarcinoma

A 76-year-old man had a diagnosis of double primary cancers consisting of poorly differentiated esophageal squamous cell carcinoma (ESCC) invading the submucosa and poorly differentiated gastric adenocarcinoma (GAC) invading the submucosa. The clinical stage of both ESCC and GAC was T1N0M0 stage I. The tumor diameter of ESCC and GAC was 20 mm and 25 mm, respectively. We performed chemoradiotherapy for ESCC. Chemotherapy consisted of nedaplatin in an intravenous dose of 90 mg/m² on day 1 and 5-fluorouracil in an intravenous dose of 800 mg/m² on days 1-5, repeated every 4 weeks for two cycles. Radiotherapy consisted of 50.4 Gy in 28 fractions for ESCC. GAC was down-staged after chemoradiotherapy for ESCC and was treated by endoscopic submucosal dissection (ESD). The tumor was histopathologically confirmed to be down-staged to intramucosal cancer with a diameter of 18 mm and no evidence of lymphovascular invasion and ulceration. Multiple metastasis occurred in the stomach, the small intestine and the colorectum after ESD. ESD is not a curative treatment even if chemotherapy is effective for poorly differentiated GAC invading the submucosa. Multiple gastrointestinal metastasis may be a unique recurrence pattern after ESD for such a lesion.

Effectiveness of salvage radiotherapy for superficial esophageal Cancer after non-curative endoscopic resection

BACKGROUND

Endoscopic resection is widely used as an effective treatment for superficial esophageal cancer. However, the risk of lymph node metastasis increases in cases of muscularis mucosae or deeper invasion, for which additional treatment such as radiotherapy or surgery is required. Accordingly, the current study investigated the efficacy and toxicity of salvage radiotherapy after non-curative endoscopic resection as an organ preservation strategy.

METHODS

We retrospectively reviewed 37 esophageal cancer patients who received salvage radiotherapy after non-curative endoscopic resection. The pathological invasion depths were the muscularis mucosae, submucosal layer, and muscularis propria in 14, 22, and one patient, respectively. All patients received external beam radiotherapy. Among them, eight received intraluminal brachytherapy following external beam radiotherapy. Elective nodal irradiation was administered to all patients. Twenty-five patients received concurrent platinum and fluorouracil-based chemotherapy.

RESULTS

The median follow-up time was 74 months (range: 3-212). The 5-year progression-free survival and overall survival rates were 64 and 78%, respectively. No local or regional lymph node recurrence was observed. The causes of death included esophageal cancer in one patient, metachronous esophageal cancer in one patient, other malignancies in eight patients, and other causes in six patients. Late cardiac toxicities ≥ grade 3 were observed in six patients, one of whom died of arrhythmia.

CONCLUSIONS

Salvage radiotherapy after non-curative esophageal endoscopic resection is an effective treatment as an organ preservation strategy. Although muscularis mucosae and submucosal cancer have a high risk of lymph node metastasis, our results suggest that elective nodal irradiation contributes to reduced regional node metastases.

Adjuvant therapy for pT1a-m3/pT1b esophageal squamous cell carcinoma after endoscopic resection: Esophagectomy or chemoradiotherapy? A critical review

Endoscopic resection (ER) combined with adjuvant therapy appears to be a new treatment for esophageal squamous cell cancers (ESCC) invading to deep mucosa (pT1a-m3) or submucosa (pT1b). Adjuvant therapy can take the form of esophagectomy or chemoradiotherapy (CRT), but it is unclear which treatment is better. This review is to explore the outcomes of adjuvant therapy between esophagectomy and CRT for the treatment of pT1a-m3/pT1b ESCC after ER. Ten relevant studies with a total of 285 patients were included. The reported 5-year overall survival rates ranged between 90-100 % for ER-esophagectomy and 75-85 % for ER-CRT. ESCC with the invasion of ≥ sm2 combined with lymphovascular involvement was associated with a high-risk of relapse in patients receiving ER-CRT, but not in ER-esophagectomy. In conclusion, patients with a high-risk of relapse should be treated with ER-esophagectomy; ER-CRT may be used as an alternative treatment for patients with a nonhigh risk of relapse.

Endoscopic detection and differentiation of esophageal lesions using a deep neural network

BACKGROUND AND AIMS

Diagnosing esophageal squamous cell carcinoma (SCC) depends on individual physician expertise and may be subject to interobserver variability. Therefore, we developed a computerized image-analysis system to detect and differentiate esophageal SCC.

METHODS

A total of 9591 nonmagnified endoscopy (non-ME) and 7844 ME images of pathologically confirmed superficial esophageal SCCs and 1692 non-ME and 3435 ME images from noncancerous lesions or normal esophagus were used as training image data. Validation was performed using 255 non-ME white-light images, 268 non-ME narrow-band images/blue-laser images, and 204 ME narrow-band images/blue-laser images from 135 patients. The same validation test data were diagnosed by 15 board-certified specialists (experienced endoscopists).

RESULTS

Regarding diagnosis by non-ME with narrow-band imaging/blue-laser imaging, the sensitivity, specificity, and accuracy were 100%, 63%, and 77%, respectively, for the artificial intelligence (AI) system and 92%, 69%, and 78%, respectively, for the experienced endoscopists. Regarding diagnosis by non-ME with white-light imaging, the sensitivity, specificity, and accuracy were 90%, 76%, and 81%, respectively, for the AI system and 87%, 67%, and 75%, respectively, for the experienced endoscopists. Regarding diagnosis by ME, the sensitivity, specificity, and accuracy were 98%, 56%, and 77%, respectively, for the AI system and 83%, 70%, and 76%, respectively, for the experienced endoscopists. There was no significant difference in the diagnostic performance between the AI system and the experienced endoscopists.

CONCLUSIONS

Our AI system showed high sensitivity for detecting SCC by non-ME and high accuracy for differentiating SCC from noncancerous lesions by ME.

Comparison of long-term outcomes between esophagectomy and chemoradiotherapy after endoscopic resection of submucosal esophageal squamous cell carcinoma

Esophagectomy represents the standard treatment strategy for superficial esophageal cancer diagnosed pathologically as submucosal disease (pT1b) following an endoscopic resection (ER). However, chemoradiotherapy (CRT) is expected to become an alternative treatment option. This study retrospectively compared the outcomes of patients who underwent ER of submucosal esophageal squamous cell carcinoma, and who received additional treatment in the form of surgery and CRT. Data were collected from 83 patients who underwent ER and were diagnosed as pT1b (sm) between January 2002 and December 2013. Of them, 52 patients underwent additional treatment (19 surgery, 33 CRT). The long-term outcomes, recurrent patterns, and recurrence risk factor were analyzed retrospectively. No significant differences were identified between the two groups regarding the following aspects: sex, Charlson comorbidity index, tumor size, macroscopic type, cut end positivity, and en bloc resection rate. On the contrary, significant differences were observed in age (P = 0.042) and lymphovascular invasion (P = 0.003) between the two groups. There were more patients with positive lymphovascular invasion, which was one of the strongest risk factors, in the surgery group. The 3-year overall survival (OS) and relapse-free survival (RFS) rates were both 100% in the surgery group and 90.4% and 87.4%, respectively, in the CRT group. The 5-year OS and RFS rates both decreased to 89.5% in the surgery group and to 80.3% and 70.4%, respectively, in the CRT group. The surgery group achieved a superior OS and RFS compared to the CRT group, though not significant (P = 0.172, P = 0.127). Tumor recurrence was observed in 6 patients. All these patients were in the CRT group (P = 0.075). They included 3 patients with hematogenous metastases (of the lung, bone, and adrenal gland) and 3 patients with regional lymph node metastasis. The patient with hematogenous adrenal gland metastasis had simultaneous extended lymph node metastasis. Through a univariate analysis, it was observed that tumor size (≥ 40 mm) and positive lymphatic invasion represented the significant risk factors for recurrence in the CRT group (P = 0.048 and P = 0.035, respectively). To achieve a better long-term survival, surgery is recommended as the additional treatment for ER-pT1b esophageal cancer. While CRT represents an acceptable alternative, the indication should be carefully decided, especially in high-risk patients for recurrence with large tumor size (≥ 40 mm) or positive lymphatic invasion.

Comparison of long-term outcomes between radical esophagectomy and definitive chemoradiotherapy in patients with clinical T1bN0M0 esophageal squamous cell carcinoma

BACKGROUND

Long-term outcomes of patients with clinical T1bN0M0 thoracic esophageal squamous cell carcinoma (ESCC) treated using radical esophagectomy were compared with those treated using definitive chemoradiotherapy (dCRT).

METHODS

A total of 320 consecutive patients with clinical T1bN0M0 thoracic ESCC who initially underwent radical esophagectomy or chemoradiotherapy during 2001-2011 were deemed eligible. Of these patients, 102 and 218 underwent radical esophagectomy and dCRT, respectively. Overall survival (OS) and causes of death were compared between the esophagectomy group and the chemoradiotherapy group.

RESULTS

Five-year OS in the esophagectomy group was significantly better than that of the chemoradiotherapy group in both the overall sample and a subset of patients aged ≥70 years (P=0.004 and P=0.040). Male patients appeared to benefit more from radical esophagectomy (P=0.005). Until 2006, radical esophagectomy yielded superior results relative to dCRT (P=0.009). However, the survival outcomes after chemoradiotherapy were non-inferior to those after esophagectomy since 2007 (P=0.255). Up to 2006, esophagectomy and chemoradiotherapy groups exhibited significant differences in the causes of death (P=0.024), such that the latter group had a significantly higher rate of deaths due to respiratory complications (P=0.025). However, the introduction of 3-dimensional radiation with CT guided planning in 2007 resolved this inter-group difference (P=0.460).

CONCLUSIONS

The appreciable developments in radiation technology have enabled the achievement of comparable long-term outcomes in the chemoradiotherapy group compared with the esophagectomy group in patients with clinical T1bN0M0 thoracic ESCC.

Classification for invasion depth of esophageal squamous cell carcinoma using a deep neural network compared with experienced endoscopists

BACKGROUND AND AIMS

Cancer invasion depth is a critical factor affecting the choice of treatment in patients with superficial squamous cell carcinoma (SCC). However, the diagnosis of invasion depth is currently subjective and liable to interobserver variability.

METHODS

We developed a deep learning-based artificial intelligence (AI) system based on Single Shot MultiBox Detector architecture for the assessment of superficial esophageal SCC. We obtained endoscopic images from patients with superficial esophageal SCC at our facility between December 2005 and December 2016.

RESULTS

After excluding poor-quality images, 8660 non-magnified endoscopic (non-ME) and 5678 ME images from 804 superficial esophageal SCCs with pathologic proof of cancer invasion depth were used as the training dataset, and 405 non-ME images and 509 ME images from 155 patients were selected for the validation set. Our system showed a sensitivity of 90.1%, specificity of 95.8%, positive predictive value of 99.2%, negative predictive value of 63.9%, and an accuracy of 91.0% for differentiating pathologic mucosal and submucosal microinvasive (SM1) cancers from submucosal deep invasive (SM2/3) cancers. Cancer invasion depth was diagnosed by 16 experienced endoscopists using the same validation set, with an overall sensitivity of 89.8%, specificity of 88.3%, positive predictive value of 97.9%, negative predictive value of 65.5%, and an accuracy of 89.6%.

CONCLUSIONS

This newly developed AI system showed favorable performance for diagnosing invasion depth in patients with superficial esophageal SCC, with comparable performance to experienced endoscopists.

Efficacy of Endoscopic Resection and Selective Chemoradiotherapy for Stage I Esophageal Squamous Cell Carcinoma

BACKGROUND & AIMS

Esophagectomy is the standard treatment for stage I esophageal squamous cell carcinoma (ESCC). We conducted a single-arm prospective study to confirm the efficacy and safety of selective chemoradiotherapy (CRT) based on findings from endoscopic resection (ER).

METHODS

We performed a prospective study of patients with T1b (SM1-2) N0M0 thoracic ESCC from December 2006 through July 2012; 176 patients underwent ER. Based on the findings from ER, patients received the following: no additional treatment for patients with pT1a tumors with a negative resection margin and no lymphovascular invasion (group A); prophylactic CRT with 41.4 Gy delivered to locoregional lymph nodes for patients with pT1b tumors with a negative resection margin or pT1a tumors with lymphovascular invasion (group B); or definitive CRT (50.4 Gy) with a 9-Gy boost to the primary site for patients with a positive vertical resection margin (group C). Chemotherapy comprised 5-fluorouracil and cisplatin. The primary end point was 3-year overall survival in group B, and the key secondary end point was 3-year overall survival for all patients. If lower limits of 90% confidence intervals for the primary and key secondary end points exceeded the 80% threshold, the efficacy of combined ER and selective CRT was confirmed.

RESULTS

Based on the results from pathology analysis, 74, 87, and 15 patients were categorized into groups A, B, and C, respectively. The 3-year overall survival rates were 90.7% for group B (90% confidence interval, 84.0%-94.7%) and 92.6% in all patients (90% confidence interval, 88.5%-95.2%).

CONCLUSIONS

In a prospective study of patients with T1b (SM1-2) N0M0 thoracic ESCC, we confirmed the efficacy of the combination of ER and selective CRT. Efficacy is comparable to that of surgery, and the combination of ER and selective CRT should be considered as a minimally invasive treatment option. UMIN-Clinical Trials Registry no.: UMIN000000553.

Prevention of esophageal stricture after endoscopic resection

Stricture formation after esophageal endoscopic resection has a negative impact on patients' quality of life because it causes dysphagia and requires multiple endoscopic dilations. Various methods by which to prevent stricture have recently been developed and reported. Among these methods, local steroid injection is the most commonly used and is currently considered the standard method for noncircumferential resection. However, local steroid injection has a limited effect on circumferential resection. Thus, oral steroid administration is used for such cases because it may have a stronger effect than local injection. Steroid treatment, both by local injection and oral administration, is effective and low-cost; however, it may cause fragility of the esophageal wall, resulting in adverse events such as perforation during balloon dilatation. Many innovative approaches have been developed, such as tissue-shielding methods with polyglycolic acid, tissue engineering approaches with autologous oral mucosal epithelial cell sheet transplantation, and stent insertion. These methods may be promising, but they are limited by a scarcity of data. Further investigations are needed to confirm the efficacy of these methods.

Technical feasibility and oncologic safety of diagnostic endoscopic resection for superficial esophageal cancer

BACKGROUND AND AIMS

Active use of endoscopic resection (ER) for cM3-SM2 esophageal cancer may enable sufficient extent of esophageal resection and help determine the need for lymph node dissection based on histopathologic findings. However, ER preceding esophagectomy may have an adverse impact on outcomes. This study was designed to determine the technical feasibility and oncologic safety of diagnostic ER.

METHODS

A single-institution retrospective cohort study was performed between July 2008 and June 2014. During this period, 135 consecutive patients with clinical T1a-M3N0M0, T1b-SM1N0M0, and T1b-SM2N0M0 primary esophageal cancer were referred to our division. Eight patients who underwent chemoradiotherapy as primary treatment were excluded because of inadequate pathologic findings. Based on oncologic and physical factors, we categorized the remaining 127 patients into 2 groups: primary esophagectomy (n = 54) and primary ER (n = 73).

RESULTS

In all 127 patients, the 3-year overall survival (OS) and disease-free survival (DFS) rates were 95.7% and 87.6%, respectively. No adverse event requiring surgical intervention was observed after ER. Diagnostic ER had no negative impact on surgical outcomes, DFS, and OS after esophagectomy. Fourteen patients (19.2%) of those who received primary ER underwent curative resection, whereas 11 (20.4%) who had pT1a disease, no lymphovascular invasion, and no pathologic lymph node metastasis underwent primary esophagectomy.

CONCLUSIONS

Diagnostic ER for cM3-SM2 esophageal cancer with or without subsequent esophagectomy was feasible and safe, not only from a surgical perspective but also an oncologic perspective. Approximately 20% of cM3-SM2N0M0 patients can potentially avoid undergoing additional treatment including esophagectomy using diagnostic ER.

Radiotherapy for T1N0M0 Esophageal Cancer: Analyses of the Predictive Factors and the Role of Endoscopic Submucosal Dissection in the Local Control

Several therapeutic options are available for clinical T1N0M0 thoracic esophageal squamous cell carcinoma (stage I ESCC); however, the studies on the treatment results are limited. This study assessed the outcomes of stage I ESCC treated with radiotherapy (RT), determined predictive factors, and evaluated the benefits of endoscopic submucosal dissection (ESD) combined with RT. We retrospectively analyzed the data of 50 patients (41 men, 9 women; median age, 66 years) with stage I ESCC treated with RT. The median total irradiation dose was 50 Gy. Elective nodal irradiation (ENI) was performed in 17 patients and ESD in 29 patients (ESD group). Forty-six patients concurrently received chemotherapy with RT. The median tumor length of ESD and non-ESD groups was 2.3 and 5 cm, respectively. The median follow-up was 33 months. The 3-year overall survival, disease-free survival (DFS), and local control (LC) rates were 77.3%, 61.1%, and 88.1%, respectively. Grade 3 adverse events occurred in 14 patients. T stage and tumor length were significant prognostic factors for 3-year DFS and 3-year LC, respectively. ESD appeared to be an important prognostic factor for LC. ENI and total irradiation dose above 50.4 Gy were not predictive factors. Our findings might help in treatment decisions for stage I ESCC.

Long-term results of concurrent chemoradiotherapy with daily-low-dose continuous infusion of 5-fluorouracil and cisplatin (LDFP) for Stage I-II esophageal carcinoma

We investigated long-term treatment outcomes and the feasibility of chemoradiotherapy consisting of daily-low-dose 5-fluorouracil and cisplatin (LDFP) chemotherapy plus radiotherapy for Stage I-II squamous cell esophageal cancer. Treatment records from the 2000 through 2008 period were reviewed retrospectively. Fractionated radiotherapy was performed with a total dose of 60 Gy delivered in 2 Gy per fraction. LDFP chemotherapy, as continuous infusion of 200 mg/m2 5-fluorouracil combined with one hour infusion of 4 mg/m2 cisplatin, was administered on the same days as radiotherapy. Survival was calculated by the Kaplan-Meier method. Survival, responses, failure patterns, and toxicities were evaluated. Seventy-six (47 stage I and 29 stage II) patients were analyzed with a median follow-up of 93.6 months. The 8-year overall survival (OS), progression-free survival (PFS) and cause-specific survival (CSS) rates were 63.4%, 49.8%, and 76.7%, respectively. The 8-year OS, PFS, and CSS for stage I and stage II patients were 71.0%/56.1%/82.9% and 45.2%/40.2%/66.6%, respectively. Sixty-eight patients (89.5%) completed the treatment regimen. A complete response (CR) was achieved in 68 patients (89.5%). Twenty-five patients (36.8%) experienced recurrence after CR. The failure patterns were (overlap included): local failure (n = 12), nodal metastasis (n = 12), distant metastasis (n = 3), details unknown (n = 2). Salvage therapy was performed for local failure; endoscopic therapy (n = 7) or surgery (n = 2). Six patients remain alive without relapse after salvage endoscopic therapy. Major Grade 3 or higher acute adverse events were leukopenia (22%), anorexia (17%), and esophagitis (11%). Major late toxicities (Grade 3 or 4) involved pericardial effusion (12%), pleural effusion (4%), and esophageal stenosis (3%). Chemoradiotherapy with LDFP provided favorable long-term survival with acceptable toxicity for Stage I-II squamous cell esophageal cancer. The tumor response was excellent, but close endoscopic follow-up is essential for detecting and treating local recurrence.

A comparison of the clinical outcomes of esophagectomy and chemoradiotherapy after noncurative endoscopic submucosal dissection for esophageal squamous cell carcinoma

PURPOSE

Endoscopic submucosal dissection (ESD) is widely used to treat esophageal cancer, but some patients require additional treatment due to the possibility of lymph node metastasis. The aim of this study was to elucidate the clinical outcomes of these additional treatments.

METHODS

The study included 59 patients who developed superficial esophageal squamous cell carcinoma after noncurative ESD treated between 2005 and 2016, of whom 28 underwent esophagectomy and 31 received chemoradiotherapy (CRT).

RESULTS

The median follow-up periods were 45 months in the esophagectomy group and 41 months in the CRT group. The overall survival did not differ significantly between the groups (P = 0.46). However, there were no recurrences in the esophagectomy group, and the disease-specific survival rate was significantly higher in this group (P = 0.042). Among the patients at high risk for recurrence due to massive tumor invasion (≥ SM2) with lymphovascular invasion (esophagectomy group, six patients; CRT group, ten patients), none in the esophagectomy group had recurrence, whereas four in the CRT group died of esophageal cancer (P = 0.031).

CONCLUSION

The overall survival did not differ significantly between the groups. However, compared with CRT, esophagectomy provided more favorable disease control for patients with massive tumor invasion (≥ SM2) with lymphovascular invasion.

Endoscopic resection with adjuvant chemo-radiotherapy for superficial esophageal squamous cell carcinoma: A critical review

Radical esophagectomy with extended lymph node dissection is considered the standard of care in treatment of squamous cell carcinoma of esophagus with deep mucosal invasion (pT1a m3) or submucosal involvement (pT1b). However, despite the increasing use of minimally invasive approaches, it remains a major surgery associated with significant morbidities and even mortality risk. Endoscopic resection (ER) results in excellent local control in early superficial mucosal (pT1a) disease yet there is substantial risk of lymph node metastases in T1b disease. Therefore, ER followed by combined with chemo-radiotherapy (CRT) would potentially improve the outcome in pT1a m3 or pT1b disease and would be an attractive conservative alternative to esophagectomy. Retrospective series published so far have shown promising results for this combined treatment. Herein the current literature of the indications, treatment outcome and toxicities of this treatment strategy are discussed and critically reviewed.

Impact of electrosurgical unit mode on post esophageal endoscopic submucosal dissection stricture in an in vivo porcine model

BACKGROUND AND AIM

 Strictures are a major complication of esophageal endoscopic submucosal dissection (ESD) for superficial esophageal carcinoma. Post ESD, stricture develops during the process of scar formation, which is related to inflammation caused by ESD. We planned a study to evaluate whether certain electrosurgical unit modes could attenuate strictures after esophageal ESD.

METHODS

 A total of 16 ESD, three-quarters of the esophageal circumference, were performed in four live pigs. A ball-tip Flush knife was used for mucosal incision. Submucosal dissection was performed using a Hook knife in monopolar mode and a ball-tip Jet B-knife in bipolar mode. Applied electrosurgical unit modes were FORCED COAG, SWIFT COAG, SPRAY COAG, ENDO CUT in monopolar mode, and FORCED COAG in bipolar mode. One month after ESD, the pigs were killed humanely and the severity of strictures and fibrosis was assessed.

RESULTS

 The resected site in the esophagus showed complete mucosal regrowth and scar formation in all pigs. The quotients of stricture following ENDO CUT, SWIFT COAG, FORCED COAG effect2, FORCED COAG effect3, FORCED COAG effect4, SPRAY COAG, and Bipolar FORCED COAG mode were 16 %, 28 %, 38 %, 33 %, 51 %, 39 %, and 47 %, respectively. The equivalent quotients of fibrosis were 7 %, 28 %, 31 %, 30 %, 35 %, 63 %, and 100 %, respectively. ENDO CUT mode was associated with the lowest mean quotients of stricture and fibrosis.

CONCLUSION

 ENDO CUT mode showed promising results to attenuate fibrosis and strictures after esophageal ESD.

Comparison between neoadjuvant chemotherapy followed by surgery and definitive chemoradiotherapy for overall survival in patients with clinical Stage II/III esophageal squamous cell carcinoma (JCOG1406-A)

Background

Neoadjuvant chemotherapy followed by surgery (NAC-S) represents the standard treatment for patients with Stage II/III esophageal squamous cell carcinoma (ESCC) in Japan. Chemoradiotherapy (CRT) is performed in patients who refuse or have contraindications to surgery. However, randomized clinical trials that compare NAC-S with CRT have not been conducted. The aim of this study was to explore subgroups of patients undergoing CRT to identify those with survival outcomes potentially equivalent to NAC-S.

Methods

Pooled data from two clinical trials in patients with Stage II/III ESCC, the JCOG9907 trial and the JCOG9906 trial were used. JCOG9907 demonstrated that NAC-S resulted in superior overall survival (OS) compared with surgery followed by adjuvant chemotherapy. JCOG9906 was a single-arm trial that explored the efficacy and safety of CRT. The eligibility criteria in the two trials were almost identical. Subgroup analyses of clinical data (serum albumin, cT, cN, cstage and tumor location) were conducted with Cox proportional hazards regression models for patients assigned to receive NAC-S in JCOG9907 and patients in JCOG9906.

Results

The analysis comprised 163 patients from JCOG9907 in NAC-S arm (NAC-S group) and 73 patients from JCOG9906 who received CRT (CRT group). Baseline characteristics were similar between the two groups. OS was better in the NAC-S group than the CRT group (adjusted hazard ratio 1.72; 95% confidence interval 1.19-2.50). All subgroups in the NAC-S group had longer OS compared with those in the CRT group.

Conclusions

OS was superior after NAC-S rather than CRT. None of the CRT subgroups had similar OS to the NAC-S groups.

Clinicopathologic Features of Submucosal Esophageal Squamous Cell Carcinoma

BACKGROUND

The prognoses of submucosal esophageal squamous cell carcinoma patients vary. Patients with favorable prognoses may receive less invasive or nonsurgical interventions, whereas patients with poor prognoses or advanced esophageal cancer may require aggressive treatments. We sought to identify prognostic factors for patients with submucosal esophageal squamous cell carcinoma, focusing on lymph node metastasis and recurrence.

METHODS

We included 137 submucosal esophageal squamous cell carcinoma patients who had undergone transthoracic esophagectomy with systematic extended lymph node dissection. Submucosal tumors were classified as SM1, SM2, and SM3 according to the depth of invasion. Prognostic factors were determined by univariable and multivariable analyses.

RESULTS

Lymph node metastasis was observed in 18.8%, 30.5%, and 50.0% of SM1, SM2, and SM3 cases, respectively. The overall 5-year recurrence rate was 21.9%; the rates for SM1, SM2, and SM3 tumors were 9.4%, 18.6%, and 34.8%, respectively. The SM1 tumors all recurred locoregionally; distant metastasis occurred in SM2 and SM3 cases. The 5-year overall survival rates were 83%, 77%, and 59% for SM1, SM2, and SM3 cases, respectively. On univariable analysis, lymph node metastasis, depth of submucosal invasion (SM3 versus SM1/2), and tumor location (upper thoracic versus mid/lower thoracic) were poor prognostic factors for overall survival. Multivariable Cox regression analyses identified depth of submucosal invasion (hazard ratio 2.51, 95% confidence interval: 1.37 to 4.61) and tumor location (hazard ratio 2.43, 95% confidence interval: 1.18 to 4.63) as preoperative prognostic factors.

CONCLUSIONS

Tumor location (upper thoracic) and infiltration (SM3) are the worse prognostic factors of submucosal esophageal squamous cell carcinoma, but lymph node metastasis is not a predictor of poorer prognosis.

Efficacy and Safety of Endoscopic Resection Followed by Chemoradiotherapy for Superficial Esophageal Squamous Cell Carcinoma: A Retrospective Study

OBJECTIVES

The reported 1- and 3-year overall survival rates after esophagectomy for stage I superficial esophageal squamous cell carcinoma (SESCC) are 95-97% and 86%, and those after definitive chemoradiotherapy (CRT) are 98% and 89%, respectively. This study was performed to elucidate the efficacy and safety of another treatment option for SESCC: endoscopic resection (ER) followed by CRT.

METHODS

We retrospectively reviewed the overall survival, recurrence, and grade ≥3 adverse events of consecutive patients who refused esophagectomy and underwent ER followed by CRT for SESCC from 1 January 2006 to 31 December 2012.

RESULTS

In total, 66 patients with SESCC underwent ER followed by CRT during the study period, and complete follow-up data were available for all patients. The median age was 67 (range, 45-82) years, and the median observation period was 51 (range, 7-103) months. Local and metastatic recurrences occurred in 2 (3%) and 6 (9%) patients, respectively, and 17 (26%) patients died. The 1-, 3-, and 5-year overall survival rates were 98%, 87%, and 75%, respectively. One of the 23 patients with mucosal cancer and 5 of 43 with submucosal cancer developed metastatic recurrences (P=0.65). Five of the 61 patients with negative vertical resection margin and 1 of 5 with positive vertical resection margin developed metastatic recurrences (P=0.39). None of the 30 patients without lymphovascular involvement developed metastatic recurrences; however, 6 of 36 patients with lymphovascular involvement developed metastatic recurrences (P=0.0098). Grade ≥3 adverse events occurred in 21 (32%) patients and all adverse events were associated with CRT, hematological adverse events in 13 (20%), and non-hematological adverse events in 9 (14%).

CONCLUSIONS

ER followed by CRT provides survival comparable with that of esophagectomy or definitive CRT and has a low local recurrence rate. A particularly favorable outcome is expected for cancers without lymphovascular involvement.

Endoscopic imaging modalities for diagnosing invasion depth of superficial esophageal squamous cell carcinoma: a systematic review and meta-analysis

BACKGROUND

Diagnosis of cancer invasion depth is crucial for selecting the optimal treatment strategy in patients with gastrointestinal cancers. We conducted a meta-analysis to determine the utilities of different endoscopic modalities for diagnosing invasion depth of esophageal squamous cell carcinoma (SCC).

METHODS

We conducted a comprehensive search of MEDLINE, Cochrane Central, and Ichushi databases to identify studies evaluating the use of endoscopic modalities for diagnosing invasion depth of superficial esophageal SCC. We excluded case reports, review articles, and studies in which the total number of patients or lesions was <10.

RESULTS

Fourteen studies fulfilled our criteria. Summary receiver operating characteristic curves showed that magnified endoscopy (ME) and endoscopic ultrasonography (EUS) performed better than non-ME. ME was associated with high sensitivity and a very low (0.08) negative likelihood ratio (NLR), while EUS had high specificity and a very high (17.6) positive likelihood ratio (PLR) for the diagnosis of epithelial or lamina propria cancers. NLR <0.1 provided strong evidence to rule out disease, and PLR >10 provided strong evidence of a positive diagnosis.

CONCLUSIONS

EUS and ME perform better than non-ME for diagnosing invasion depth in SCC. ME has a low NLR and is a reliable modality for confirming deep invasion of cancer, while EUS has a high PLR and can reliably confirm that the cancer is limited to the surface. Effective use of these two modalities should be considered in patients with SCC.

TRIAL REGISTRATION

PROSPERO (International Prospective Register of Systematic Reviews); number 42015024462 .

Long-term complications of definitive chemoradiotherapy for esophageal cancer using the classical method

Chemoradiation therapy is widely used to treat both inoperable and operable patients, and is less invasive than surgery. Although the number of long-term survivors who have received chemoradiation therapy is increasing, the long-term toxicity pattern and cumulative incidence of toxicity regarding this modality are poorly understood. Classically, chemoradiation therapy for esophageal cancer consists of an anterior-posterior field and a subsequent oblique boost field. We retrospectively analyzed patients who were treated with definitive chemoradiation therapy for esophageal cancer using this classical method from 1999 to 2008. For the assessment of toxicity, the National Cancer Institute Common Toxicity Criteria Version 3.0 was adopted. A total of 101 patients were analyzed. The median follow-up time was 16 months for all patients and 62 months for the surviving patients. Eleven patients experienced late toxicities of ≥Grade 3. Two patients died of late toxicities. The 3- and 5-year cumulative incidences for the first late cardiopulmonary toxicities of ≥Grade 3 were 17.4% and 20.8%, respectively. Cardiopulmonary effusions were observed within the first 3 years of completion of the initial treatment in seven out of eight patients. Sudden death and cardiac ischemia were observed over a 10-year period. Older age was found to be a risk factor for late toxicity after definitive chemoradiation therapy for esophageal cancer. Substantial toxicities were observed in patients who had received chemoradiation therapy for esophageal cancer using the classical method. To minimize the incidence of late toxicity, more sophisticated radiation techniques may be useful.

Distant lymph node metastases caused by esophageal cancer invasion to the lamina propria: a case report

Background

Pathological examination after endoscopic submucosal dissection revealed that a 62-year-old male had esophageal squamous cell carcinoma with lamina propria mucosal invasion and lymphatic permeation.

Case presentation

The patient underwent subtotal esophagectomy and reconstruction as an additional therapy. At 3 years and 4 months after esophagectomy, enlargement of abdominal para-aortic lymph nodes metastases was detected by computed tomography scanning. A total of 50.4 Gy of radiation and two cycles of 5-fluorouracil plus cisplatin were administered. The lymph node metastases were markedly reduced by chemoradiotherapy; however, at 1 year and 1 month later (4 years and 5 months after esophagectomy), left adrenal gland recurrence was found. Although resection was performed, the patient died from cancer progression at 5 years and 4 months after esophagectomy.

Conclusions

This case demonstrates that esophageal squamous cell carcinoma with invasion to the lamina propria and lymphatic permeation has the potential to cause distant metastases.

Evaluation of safety profile of thoracoscopic esophagectomy for T1bN0M0 cancer using data from JCOG0502: a prospective multicenter study

BACKGROUND

Thoracoscopic esophagectomy is rapidly and increasingly being used worldwide because it is a less invasive alternative to open esophagectomy. However, few prospective multicenter studies have evaluated its safety profile. This study aimed to evaluate the safety profile of thoracoscopic esophagectomy using perioperative data from the Japan Clinical Oncology Group Study (JCOG0502).

METHODS

JCOG0502 is a four-arm prospective study comparing esophagectomy with chemoradiotherapy for esophageal cancer, with randomized and patient preference arms. Patients with clinical stage T1bN0M0 esophageal cancer were enrolled until patient accrual was completed. Open or thoracoscopic esophagectomy was selected at the surgeon's discretion. Perioperative complications were defined as adverse events of ≥grade 2 as per Common Terminology Criteria for Adverse Events ver. 3.0.

RESULTS

A total of 379 patients were enrolled between December 2006 and February 2013. Of the 210 patients who underwent surgery, 109 patients underwent open esophagectomy, and 101 patients underwent thoracoscopic esophagectomy. Although thoracoscopic esophagectomy decreased the incidence of postoperative atelectasis (open: 22.0%, thoracoscopy: 10.9%; P = 0.041), reoperation was more frequent in the thoracoscopy group (open: 1.8%, thoracoscopy: 9.9%; P = 0.016). The incidence of overall complications did not differ between the two groups (open: 44.0%, thoracoscopy: 44.6%; P = 1.00). There was one in-hospital death in each group (open: 0.9%, thoracoscopy: 1.0 %; P = 1.00).

CONCLUSIONS

Thoracoscopic esophagectomy is a safe procedure with morbidity and mortality comparable with those of open esophagectomy. However, it is associated with a higher frequency of reoperation.

Endoscopic Submucosal Dissection (ESD) with Additional Therapy for Superficial Esophageal Cancer with Submucosal Invasion

OBJECTIVE

The standard treatment for submucosal esophageal cancer is esophagectomy or chemoradiotherapy (CRT). However, these treatment modalities could deteriorate the general condition and quality of life of the patients who are intolerant to invasive therapy. It is therefore important and beneficial to develop less invasive treatment protocols for these patients.

METHODS

The study included 43 patients who were clinically suspected of mucosa or submucosal esophageal cancer but underwent endoscopic submucosal dissection (ESD) as a primary treatment, due to the patients' poor performance statuses and/or preferences for less invasive therapy. According to the pathological findings and patient's general condition, whether the patient underwent additional treatments or remained hospitalized without additional treatments was thereafter decided for each patient. We retrospectively analyzed the outcomes of these patients.

RESULTS

Fifteen patients underwent additional surgery, 11 patients underwent CRT/radiation therapy (RT) and 17 patients were followed without additional treatments. During the 3-year follow-up period, the relapse-free survival rates in the patients who received or did not receive additional treatments were 88% and 64%, respectively (95% confidence interval, 0.45-0.76, p=0.04). The relapse-free and overall survival rates in the patients with additional treatments were equivalent or superior to those described in previous reports of the standard treatments. Preceding ESD contributed to reduce the local relapse significantly to approximately 3.5% and additional CRT-related toxicities.

CONCLUSION

Preceding ESD is very effective for the local control of cancer, and useful for histologically confirming the high-risk factors of relapse, such as ≥submucosal layer 2 (SM2) invasion and lymphovascular involvements. ESD with additional therapy may be a promising strategy for optimizing the selection of therapy depending on the patient's general condition.

Endoscopic optical diagnosis provides high diagnostic accuracy of esophageal squamous cell carcinoma

Background

Recent technological advances have stimulated the development of endoscopic optical biopsy technologies. This study compared the accuracy of endoscopic diagnosis using magnifying narrow-band imaging (NBI) and histologic diagnosis of esophageal squamous lesions.

Methods

Patients at high risk for esophageal squamous cell carcinoma were examined with endoscopy and subsequent biopsy. The lesions diagnosed as cancer on NBI and the lesions diagnosed as cancer on biopsy were resected endoscopically or surgically. Histological diagnoses of resected specimens, the reference standards in this study, were made by a pathologist who was blind to both the endoscopic and biopsy diagnoses. The primary outcome was the accuracy of endoscopic and biopsy diagnosis. A noninferiority trial design with a noninferiority margin of −10% was chosen to investigate the accuracy of endoscopic diagnosis using magnifying NBI.

Results

Between November 2010 and October 2012, a total of 111 lesions in 85 patients were included in the analysis. The accuracy of endoscopic diagnosis and biopsy diagnosis for all lesions was 91.0% (101/111) and 85.6% (95/111), respectively. The difference in diagnostic accuracy was 5.4% (95% confidence interval: −2.9%–13.7%). The accuracy of endoscopic diagnosis and biopsy diagnosis of invasive cancers was 94.9% (74/78) and 84.6% (66/78), respectively. The difference was 10.3% (95% confidence interval: 1.6%–19.0%) for invasive cancers. The lower bound of the 95% confidence interval was above the prestated −10% in both cases.

Conclusion

Noninferiority of endoscopic diagnosis by magnifying NBI to histologic diagnosis by biopsy was established in this study (p = 0.0001).

Trial registration

The study was registered on 9^th November 2010 in the University Hospital Medical Network Clinical Trials Registry as number: UMIN000004529.

Randomized study of two endo-knives for endoscopic submucosal dissection of esophageal cancer

OBJECTIVES

Settings for endoscopic submucosal dissection (ESD) of esophageal cancer have not been standardized, and no studies have directly compared ESD devices in humans.

METHODS

We conducted a randomized study to compare the performances of two different endo-knives, the Flush knife and Mucosectom, for esophageal ESD in 48 lesions. All procedures were initiated by two endoscopists, who were assisted by senior endoscopists with verbal advice. In the Flush-knife group, mucosal incision with a 2-mm Flush knife was followed by submucosal dissection using a 1-mm Flush knife. In the Mucosectom group, mucosal incision with a 2-mm Flush knife was followed by submucosal dissection with a Mucosectom. The primary outcome variable was the procedure time required for submucosal dissection. The secondary outcome variables were total procedure time, self-completion rates, and adverse events.

RESULTS

Total procedure time in the Mucosectom group was significantly shorter than in the Flush-knife group (57±21 vs. 83±27 min, respectively; P<0.001). The submucosal-dissection time in the Mucosectom group was significantly shorter than in the Flush-knife group (40±18 vs. 61±23 min, respectively; P<0.001). The self-completion rate in the Mucosectom group was slightly higher than in the Flush-knife group, but the difference was not significant (91.7% vs. 75%, respectively; P=0.25). One perforation and one postoperative bleeding occurred in the Flush-knife group, both of which were treated successfully by endoscopic treatment.

CONCLUSIONS

The Mucosectom reduced the procedure and submucosal-dissection times of esophageal ESD, without increasing adverse events.