Prognostic factors in clinical T1N0M0 thoracic esophageal squamous cell carcinoma invading the muscularis mucosa or submucosa

Esophagectomy Versus Endoscopic Resection with Adjuvant Therapy for T1b/T2 Esophageal Cancer: A Systematic Review and Meta-Analysis

Esophageal cancer is the seventh most common cause of cancer-related death worldwide [...].

Clinical outcomes and prognostic factors of volumetric modulated arc therapy (VMAT) of esophageal cancer

Background

The objective was to evaluate the efficacy and safety of radiotherapy and the prognostic factors in patients with esophageal cancer who received definitive radiotherapy, using volumetric modulated arc therapy (VMAT).

Materials and methods

Forty-seven patients who received definitive radiotherapy using VMAT between September 2017 and December 2020 were enrolled. Prescription doses were 60 Gy in 30 fractions to the planning target volume (PTV) primary and 48 Gy in 30 fractions to the PTV subclinical. Overall survival (OS), progression free survival (PFS), and toxicity were analyzed, and univariate and multivariate analyses were used to investigate the prognostic factors.

Results

Median follow up time was 10 months. Most of the patients had an advanced disease stage (stage I, 12.8%; II, 8.5%; III, 27.7%; IV, 51.0%) patients (38.3%) had a T4 tumor. The median survival time was 14 months (range: 0-56 months). The 2-year OS and PFS were 31.3% and 20.4%, respectively. Acute adverse events (≥ Grade 3) were observed in 25 patients (53.2%), and the most frequent types were dysphagia, hematological toxicities including leukopenia, and febrile neutropenia in 14 (29.8%), 10 (21%), and 10 (21%) patients, respectively. Late adverse events (Grade 3 or higher) were observed in eight patients (17.0%), and the most frequent types were pneumonitis in four patients (8.5%), and Grade 5 in one patient (2.1%; esophageal fistula). In multivariate analysis, neutrophil-to-lymphocyte ratio (NLR) > 3 (p = 0.026) was significantly associated with poor survival.

Conclusion

Definitive radiotherapy of 60Gy with VMAT is feasible and safe for patients with esophageal cancer. Pre-treatment NLR >3 was an independent prognostic factor for OS.

Radiotherapy Improves Survival of Patients With Lymphovascular Invasion in pT1b Esophageal Squamous Cell Cancer After Endoscopic Submucosal Dissection

INTRODUCTION

Adjuvant radiotherapy is recommended for pT1b esophageal squamous cell cancer (ESCC) after endoscopic submucosal dissection (ESD). However, it is unclear whether additional radiotherapy can improve patient survival. This study aimed to evaluate the efficacy of adjuvant radiotherapy after ESD for pT1b ESCC.

METHODS

This was a multicenter, cross-sectional study involving 11 hospitals in China. Between January 2010 and December 2019, patients with T1bN0M0 ESCC treated with or without adjuvant radiotherapy after ESD were included. Survival between groups was compared.

RESULTS

Overall, 774 patients were screened, and 161 patients were included. Forty-seven patients (29.2%) received adjuvant radiotherapy after ESD (RT group) and 114 (70.8%) underwent ESD alone (non-RT group). There were no significant differences in overall survival (OS) and disease-free survival (DFS) between the RT and non-RT groups. Lymphovascular invasion (LVI) was the only prognostic factor. In the LVI+ group, adjuvant radiotherapy significantly improved survival (5-year OS: 91.7% vs 59.5%, P = 0.050; 5-year DFS: 92.9% vs 42.6%, P = 0.010). In the LVI- group, adjuvant radiotherapy did not improve survival (5-year OS: 83.5% vs 93.9%, P = 0.148; 5-year DFS: 84.2% vs 84.7%, P = 0.907). The standardized mortality ratios were 1.52 (95% confidence interval 0.04-8.45) in the LVI+ group with radiotherapy and 0.55 (95% confidence interval 0.15-1.42) in the LVI- group without radiotherapy.

DISCUSSION

Adjuvant radiotherapy could improve survival in pT1b ESCC with LVI+ other than LVI- after ESD. Selective adjuvant radiotherapy based on LVI status achieved survival rates similar to those of the general population.

Long-Term Clinical Outcomes and Safety Analysis of Superficial Esophageal Cancer Patients Treated with Definitive or Adjuvant Radiotherapy

(1) Background: The role of radiotherapy (RT) in superficial esophageal squamous cell cancer (ESCC) remains unclear. The objective of our study was to perform a detailed outcome and safety analysis of RT as a definitive or adjuvant treatment for T1N0M0 staged ESCC patients. (2) Methods: A total of 55 patients treated with endoscopic resection (ER) + RT/concurrent chemoradiotherapy (CCRT) or RT/CCRT from January 2011 to June 2021 were included in this study. Eighteen patients with risk factors received ER + RT/CCRT, and thirty-seven patients solely received RT/CCRT. Kaplan-Meier curves were used to calculate the clinical outcomes, and toxicities were scored. (3) Results: The median follow-up time was 51.9 months. The estimated 5-year local recurrence-free survival (LRFS) and overall survival (OS) were 88.9% and 94.4% in the ER + RT/CCRT group and 91.8% and 91.7% in the RT/CCRT group. The predominant failure pattern was in-field local failure (5.5%, 3/55), with one patient in the ER + RT/CCRT group and two patients in the RT/CCRT group. One patient (1.8%, 1/55) had lung metastasis in the RT/CCRT group. The most common toxicities were Grades 1-2 in all patients, including esophagitis (74.5%, 41/55), myelosuppression (49.1%, 27/55) and esophageal stricture after RT (27.3%, 15/55). Two patients (11.1%, 2/18) and four patients (10.8%, 4/37) had Grade 3 esophageal stricture after RT in the ER + RT/CCRT group and RT/CCRT group, respectively. No patients experienced a Grade 4 or higher toxicity, and there were no treatment-related deaths. (4) Conclusions: Definitive or adjuvant RT/CCRT is an effective treatment alternative for superficial ESCC patients with satisfactory clinical outcomes and acceptable toxicities.

Best additional management after non-curative endoscopic resection of esophageal squamous cell carcinoma: a systematic review and meta-analysis

INTRODUCTION

Endoscopic resection (ER) is an accepted first-line treatment for superficial esophageal squamous cell carcinoma (ESCC), but when curative resection is not achieved, further treatment is not standardised. We aimed at evaluating outcomes of management strategies (esophagectomy, chemoradiotherapy/radiotherapy (CRT/RT) or follow-up (FUP)) after a non-curative ESCC ER.

METHODS

A systematic review was performed evaluating outcomes of different management strategies after ESCC submitted to primary ER (T1a/T1b), without curative criteria (R1/Rx, T1a-m3/T1b, lymphovascular invasion (LVI) or poor differentiation). Primary outcomes included recurrence, overall survival (OS) and cancer-specific survival (CSS). Secondary outcomes consisted of treatment-related adverse events.

RESULTS

Seventeen studies were included for qualitative analysis (16 observational and 1 randomized controlled trial) including 788 patients with ESCC submitted to ER, managed by additional CRT/RT (n = 530), surgery (n = 98) or FUP (n = 160). Eight studies suited quantitative analysis. Patients only followed up after ER experienced recurrence rates of 0-36.4% (OR 3.6 (95%CI 1.06-12.20) vs further treatments). When submitted to CRT/RT following non-curative ER, recurrence was observed in 0-27.2% (OR 8.00 (95%CI 1.74-36.80) whereas after surgery no recurrence was noticeable. Reported 5 y-OS after CRT/RT for non-curative ER ranged among 75-100% whereas, for those offered surgeries, 5 y-OS was 89.5%. OS ranged between 54.5% and 100% after FUP. CRT/RT and surgery-related adverse events ranged from 0% to 32% and 14% to 28.5%.

CONCLUSIONS

Additional treatment should be provided in ESCC after non-curative ER. Adjuvant esophagectomy might be the preferred treatment to medically fit patients with high-risk features (namely LVI). Properly designed trials assessing the role of CRT/RT are needed to manage these patients.

Endoscopic resection as an independent predictive factor of local control in patients with T1bN0M0 esophageal squamous cell carcinoma treated with chemoradiotherapy: a retrospective study

Background

Although chemoradiotherapy (CRT) is one of the curative treatments for thoracic esophageal squamous cell carcinoma (ESCC) with submucosal invasion, the risk of local recurrence after CRT remains a clinical problem. This retrospective study aimed to analyze the predictive factors for local recurrence after CRT.

Methods

Ninety-one patients with clinical or pathological (c/p) T1bN0M0 thoracic ESCC who underwent CRT from 2004 to 2017 in our institution were analyzed retrospectively. Sixty-three patients were diagnosed with pathological T1b after undergoing initial endoscopic resection (ER) and treated with additional CRT; meanwhile, 28 patients were clinically diagnosed with T1b and underwent definitive CRT. We investigated the predictors of disease–specific survival (DSS) and local recurrence–free survival (LRFS) by performing univariate and multivariate analyses.

Results

The median observation period was 59.8 months. The 5-year DSS and LRFS rates were 84.3% (95% confidence interval [CI]: 76.1–92.5) and 87.1% (95% CI: 79.1–95.1), respectively. The multivariate analysis revealed no significant predictors associated with DSS. On the contrary, ER (hazard ratio [HR]: 0.11, 95% CI: 0.02–0.48, p = 0.003) and tumor length (HR: 6.78, 95% CI: 1.28–36.05, p = 0.025) were recognized as independent predictive factors for LRFS. During follow-up, recurrence was observed in 18 patients (19.8%). With regard to the patterns of relapse, local recurrence was the most common in 11 patients, and salvage ER was performed in 9 of 11 patients.

Conclusions

ER and tumor length were independent predictive factors for LRFS. Our study suggested that performance of ER prior to CRT improved the local control in patients with c/p T1bN0M0 ESCC. In addition, most of the patients who experienced local recurrence were treated with salvage ER, which contributed to preserving the organs.

Additional Radiotherapy With or Without Chemotherapy Following Endoscopic Resection for Stage I Esophageal Carcinoma: A Pilot Study

Objective: To evaluate the safety and efficacy of additional radiotherapy after endoscopic resection (ER) for stage I esophageal carcinoma (EC) with high-risk factors. Materials and methods: Patients with stage cT1N0M0 EC who underwent ER and additional radiotherapy between January 2010 and August 2019 at our institution were retrospectively included. Overall survival (OS), disease-free survival (DFS), cancer-specific survival (CSS), local control rate, regional control rate, common acute toxicities, esophageal stricture, and dysphagia were analyzed. Results: Thirty-one consecutive patients were included in the study. The median age was 62 years (range, 49-78). Thirty patients (96.8%) had squamous cell carcinoma, and one patient (3.2%) had adenosquamous cell carcinoma. Twenty-six patients (83.9%) had submucosal invasion, 15 patients (48.4%) had lymphovascular invasion, and one patient (3.2%) had a venous invasion. The 1-, 3-, and 5-year OS rates were 100.0%, 86.9%, and 68.5%, respectively. The corresponding DFS rates were 100.0%, 85.2%, and 75.8%, respectively. The corresponding CSS rates were 100.0%, 89.8%, and 78.6%, respectively. The local and regional control rates were 100.0% and 93.5%, respectively. No grade 4-5 acute toxicities were observed. Fifteen patients (48.4%) were endoscopically diagnosed with esophageal strictures after ER. At the last follow-up, 28 patients (90.5%) were able to eat a regular diet, one patient (3.2%) could eat a soft diet, one needed a semifluid diet, and only one (3.2%) had to eat a fluid diet. Conclusions: For patients with stage I EC, additional radiotherapy following ER is safe and effective, with the swallowing function well-preserved. Nevertheless, prospective studies are needed to verify these results.

Organ Preservation after Endoscopic Resection of Early Esophageal Cancer with a High Risk of Lymph Node Involvement

Simple Summary

Virtually all early (T1) esophageal cancers can be resected endoscopically. However, the presence of histologic criteria on the resection specimen (deep submucosal invasion, lymphovascular involvement, poor tumor differentiation) are believed to be associated with a high risk (> 10%) of lymph node involvement. Therefore, the presence of such histoprognostic criteria currently require an esophagectomy. However, some patients are unfit for surgery or decline surgery, and undergo close follow-up or chemoradiotherapy. We analyzed the outcomes of these patients. We included 41 patients, of which thirteen (32%) were closely monitored, and 28 (68%) were treated by chemoradiotherapy or radiotherapy alone. After a mean follow-up of 19 and 28 months, cancer specific survival was 100% and 96%, respectively. Our study shows that close follow-up may be an alternative to esophagectomy after endoscopic resection of an early esophageal cancer with a predicted high risk of lymph node involvement.

Abstract

Background: Esophagectomy is recommended after endoscopic resection of an early esophageal cancer when pejorative histoprognostic criteria indicate a high risk of lymph node involvement. Our aim was to analyze the clinical outcomes of a non-surgical, organ preserving management in this clinical setting. Patients and Methods: This retrospective study was performed in two tertiary centers from 2015 to 2020. Patients were included if they had histologically complete resection of an early esophageal cancer, with poor differentiation, lymphovascular invasion or deep submucosal invasion. Endoscopic resection was followed by chemoradiotherapy or follow-up in case of surgical contraindications or patient refusal. Outcome measures were disease-free survival (DFS), overall survival (OS), cancer specific survival (CSS) and toxicity of chemoradiotherapy. Results: Forty-one patients (36 with squamous cell carcinoma and 5 with adenocarcinomas) were included. The estimated high risk of lymph node involvement was based on poor differentiation (10/41; 24%), lympho-vascular invasion (11/41; 27%), muscularis mucosa invasion or deep sub-mucosal invasion (38/41; 93%). Thirteen patients (13/41; 32%) were closely monitored, and 28 (28/41; 68%) were treated by chemoradiotherapy or radiotherapy alone. In the close follow-up group, DFS, OS and CSS were 92%, 92% and 100%, respectively vs. 75%, 79% and 96%, respectively in the chemoradiotherapy group at the end of the follow-up. Serious adverse events related to chemoradiotherapy occurred in 10% of the patients. There were no treatment-related deaths. Conclusions: Our study shows that close follow-up may be an alternative to systematic esophagectomy after endoscopic resection of early esophageal cancer with a predicted high risk of lymph node involvement.

Endoscopic submucosal dissection/endoscopic mucosal resection guidelines for esophageal cancer

The Japan Gastroenterological Endoscopy Society has developed endoscopic submucosal dissection/endoscopic mucosal resection guidelines. These guidelines present recommendations in response to 18 clinical questions concerning the preoperative diagnosis, indications, resection methods, curability assessment, and surveillance of patients undergoing endoscopic resection for esophageal cancers based on a systematic review of the scientific literature.

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.

Current status of esophageal cancer treatment

Esophageal cancer (EC) remains one of the most common and aggressive diseases worldwide. This review discusses some debates in the modern management of the disease. Endoscopic procedures for early cancer (T1a−b) are now embedded in routine care and the challenge will be to more accurately select patients for endoscopic resection with or without adjuvant therapy. Perioperative multimodal therapies are associated with improved survival compared to surgery alone for locally advanced esophageal cancer. However, there is no global consensus on the optimal regimen. Furthermore, histological subtype (adenocarcinomavs. squamous cell cancer) plays a role in the choice for treatment. New studies are underway to resolve some issues. The extent of the lymphadenectomy during esophagectomy remains controversial especially after neoadjuvant chemoradiation. The ideal operation balances between limiting surgical trauma and optimizing survival. Minimally invasive esophagectomy and enhanced recovery pathways are associated with decreased morbidity and faster recovery albeit there is no consensus yet what approach should be used. Finally, immune checkpoint inhibitors present promising preliminary results in the novel treatment of advanced or metastatic EC but their widespread application in clinical practice is still awaited.

The influence of adjuvant radiation therapy after endoscopic resection on survival for early stage EC: an analysis of the surveillance epidemiology and end results (SEER) database

Background

Endoscopic resection (ER) followed by radiation therapy (RT) is a treatment option for early stage esophageal cancer (EC). We used the surveillance epidemiology and end results (SEER) database to investigate the influence of adjuvant RT after ER on survival for early stage EC.

Methods

The SEER database [1998-2013] was queried for locoregional cases of EC. Tumor staging was redefined with the 8th Edition of the American Joint Committee on Cancer (AJCC)/Union for International Cancer Control tumor-node-metastasis (TNM) staging system. The T1-2 stage EC cases in which ER were followed by radiation or observation were included. Kaplan-Meier methods were performed to compare overall survival (OS) and cancer-specific survival (CSS) between the patients who received radiation and those who did not. Subgroup analysis was made according to AJCC stage. A multivariate Cox proportional-hazards regression model was used to identify independent covariates which may influence survival.

Results

The median survival of the no-radiation group was significantly longer than that of the radiation group [74 vs. 31 months; hazard risk (HR), 2.39; 95% confidence interval (CI), 1.782-3.197; P<0.001]. In T1a stage subgroup, patients who did not receive RT had significantly better OS and CSS outcomes (OS: 90 vs. 31 months; HR, 2.90; 95% CI, 1.766-4.773; P<0.001; CSS: 105 vs. 48 months; HR, 5.40; 95% CI, 2.636-8.226; P<0.001). In the T1b and T2 subgroup analyses, both the OS and CSS were not significantly different between the radiation group and the no-radiation group (all P>0.05). In multivariate regression analysis, radiation was not a significant factor for OS and CSS after adjustment for confounding factors (P>0.05).

Conclusions

Using SEER data, we revealed that RT after ER did not improve survival in early stage EC patients; specifically, RT did not benefit T1b and T2 patients and may lead to poorer survival in T1a patients. Our findings do not support the addition of RT after ER for early stage EC, especially T1a EC.

Failure patterns after adjuvant chemoradiotherapy following endoscopic resection for superficial esophageal squamous cell carcinoma

Background

This study evaluated the locations of lymph node recurrence and their association with irradiation fields used for radiotherapy after adjuvant chemoradiotherapy following endoscopic resection for superficial esophageal squamous cell carcinoma.

Methods

Medical records of 96 consecutive patients with superficial esophageal squamous cell carcinoma who underwent adjuvant chemoradiotherapy following endoscopic resection were reviewed. Computed tomography was used to identify whether nodal recurrences were within the elective nodal irradiation field. The cumulative incidence of recurrence was calculated, accounting for death as a competing risk. Univariate and multivariate analyses identified factors predicting nodal recurrence.

Results

The median follow‐up period was 61 months (range: 6‐137 months). Seven patients (7.3%) developed lymph node recurrence only; two patients (2.1%) developed nodal plus local recurrence. Six of the seven cases without local recurrence involved the elective nodal irradiation field, with five cases involving the recurrent nerve lymph nodes. The 5‐year cumulative incidence of lymph node recurrence was higher for T1b tumors with lymphovascular invasion than for T1a tumors with lymphovascular invasion (17.6% vs 6.2%, P = 0.086; HR: 3.74, 95% CI: 0.80‐17.52, P = 0.094) and T1b tumors without lymphovascular invasion (17.6% vs 3.3%, P = 0.031; HR: 6.78, 95% CI: 0.80‐57.63, P = 0.080).

Conclusions

Lymph node recurrence frequently involved the elective nodal irradiation field, with recurrent nerve lymph nodes being common metastasis sites. The high incidence of nodal recurrence for T1b tumors with lymphovascular invasion highlights a need for new strategies for treating this subset of superficial esophageal squamous cell carcinomas.

Early esophageal cancer: the significance of surgery, endoscopy, and chemoradiation

Early carcinomas of the esophagus are histologically classified as adenocarcinoma or squamous cell carcinoma and microscopically subdivided into mucosal and submucosal carcinomas depending on infiltration depth. The prevalence of lymph node metastasis in mucosal carcinoma remains low. However, lymph node metastases arise frequently from tumors with submucosal infiltration, with increasing prevalence in the deeper submucosal sublayers. According to current German guidelines, endoscopic resection is the recommended treatment in mucosal adenocarcinoma without histologic risk factors (lymphatic invasion 1, vascular invasion 1, >grade 2, R1-margin). In superficial submucosal infiltration without histologic risk factors, endoscopic resection can be considered. In squamous cell carcinoma, endoscopic resection is indicated up to middle layer mucosal carcinoma. Beyond these criteria, surgical resection should be considered. The gold standard is a subtotal transthoracic esophagectomy with two-field lymphadenectomy. Total esophagectomy is performed in cervical esophageal carcinoma and transhiatal extended gastrectomy in carcinoma of the cardia. Minimally invasive procedures show good oncologic results and reduce the morbidity of radical esophagectomy. Reduced morbidity might be an argument for surgical resection in borderline cases between endoscopic and surgical resection. In early squamous cell cancer, the combination of endoscopic resection and adjuvant chemoradiotherapy is a therapeutic option with promising results.

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.

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.

Clinical implication of endoscopic gross appearance in superficial esophageal squamous carcinoma: revisited

BACKGROUND

Standard endoscopic appearance is essential for the diagnosis and treatment of superficial esophageal squamous carcinoma (SESC). The aim of this study was to investigate the association between the endoscopic gross appearance and the clinicopathologic characteristics of SESC.

METHODS

We retrospectively analyzed the clinicopathologic characteristics of SESC according to gross endoscopic appearance in 275 patients with SESC that underwent esophagectomy or endoscopic resection (ER).

RESULTS

The proportion of type I or type III gross appearance, and that of types IIa, IIb, or IIc, were 26.2 and 73.8%, respectively. Type I or type III gross appearance was significantly associated with the female sex, submucosal invasion, lymphovascular invasion (LVI), and lymph node metastasis (LNM). In addition, younger age, larger tumor size, higher proportion of circumferential extension, type I or type III endoscopic gross appearance, submucosal invasion, moderate or poorly differentiated carcinoma, and LVI were significantly associated with LNM. Multivariate logistic regression analysis determined that independent predictors of LNM in patients with SESC included endoscopic gross appearance, submucosal invasion, and presence of LVI. Additionally, type I or type III endoscopic gross appearance lesions were more likely to have submucosal invasion than types IIa, IIb, or IIc. Risk factors for submucosal invasion included a gross appearance of type I or type III, moderately or poorly differentiated tumors, and presence of LVI.

CONCLUSIONS

We found that SESC clinical features are correlated with the endoscopic appearance. Therefore, we suggest that the endoscopic gross appearance may be a candidate for additive criteria in the indications for ER.

Intrafractional dose variation and beam configuration in carbon ion radiotherapy for esophageal cancer

Background

In carbon ion radiotherapy (CIR) for esophageal cancer, organ and target motion is a major challenge for treatment planning due to potential range deviations. This study intends to analyze the impact of intrafractional variations on dosimetric parameters and to identify favourable settings for robust treatment plans.

Methods

We contoured esophageal boost volumes in different organ localizations for four patients and calculated CIR-plans with 13 different beam geometries on a free-breathing CT. Forward calculation of these plans was performed on 4D-CT datasets representing seven different phases of the breathing cycle. Plan quality was assessed for each patient and beam configuration.

Results

Target volume coverage was adequate for all settings in the baseline CIR-plans (V₉₅ > 98% for two-beam geometries, > 94% for one-beam geometries), but reduced on 4D-CT plans (V₉₅ range 50–95%). Sparing of the organs at risk (OAR) was adequate, but range deviations during the breathing cycle partly caused critical, maximum doses to spinal cord up to 3.5x higher than expected. There was at least one beam configuration for each patient with appropriate plan quality.

Conclusions

Despite intrafractional motion, CIR for esophageal cancer is possible with robust treatment plans when an individually optimized beam setup is selected depending on tumor size and localization.