Risk Factors Associated with Esophageal Fistula after Radiotherapy for Esophageal Squamous Cell Carcinoma

Prediction of malignant esophageal fistula in esophageal cancer using a radiomics-clinical nomogram

BACKGROUND

Malignant esophageal fistula (MEF), which occurs in 5% to 15% of esophageal cancer (EC) patients, has a poor prognosis. Accurate identification of esophageal cancer patients at high risk of MEF is challenging. The goal of this study was to build and validate a model to predict the occurrence of esophageal fistula in EC patients.

METHODS

This study retrospectively enrolled 122 esophageal cancer patients treated by chemotherapy or chemoradiotherapy (53 with fistula, 69 without), and all patients were randomly assigned to a training (n = 86) and a validation (n = 36) cohort. Radiomic features were extracted from pre-treatment CTs, clinically predictors were identified by logistic regression analysis. Lasso regression model was used for feature selection, and radiomics signature building. Multivariable logistic regression analysis was used to develop the clinical nomogram, radiomics-clinical nomogram and radiomics prediction model. The models were validated and compared by discrimination, calibration, reclassification, and clinical benefit.

RESULTS

The radiomic signature consisting of ten selected features, was significantly associated with esophageal fistula (P = 0.001). Radiomics-clinical nomogram was created by two predictors including radiomics signature and stenosis, which was identified by logistic regression analysis. The model showed good discrimination with an AUC = 0.782 (95% CI 0.684-0.8796) in the training set and 0.867 (95% CI 0.7461-0.987) in the validation set, with an AIC = 101.1, and good calibration. When compared to the clinical prediction model, the radiomics-clinical nomogram improved NRI by 0.236 (95% CI 0.153, 0.614) and IDI by 0.125 (95% CI 0.040, 0.210), P = 0.004.

CONCLUSION

We developed and validated the first radiomics-clinical nomogram for malignant esophageal fistula, which could assist clinicians in identifying patients at high risk of MEF.

Clinical-radiomics nomogram for the risk prediction of esophageal fistula in patients with esophageal squamous cell carcinoma treated with intensity-modulated radiation therapy or volumetric-modulated arc therapy

Background

Esophageal fistula (EF) is a serious adverse event as a result of radiotherapy in patients with esophageal cancer (EC). We aimed to identify the predictive factors and establish a prediction model of EF in patients with esophageal squamous cell carcinoma (ESCC) who underwent intensity-modulated radiation therapy (IMRT) or volumetric-modulated arc therapy (VMAT).

Methods

Patients with ESCC treated with IMRT or VMAT from January 2013 to December 2020 at Xijing Hospital were retrospectively analyzed. Ultimately, 43 patients with EF and 129 patients without EF were included in the analysis and propensity-score matched in a 1:3 ratio. The clinical characteristics and radiomics features were extracted. Univariate and multivariate stepwise logistic regression analyses were used to determine the risk factors associated with EF.

Results

The median follow-up time was 24.0 months (range, 1.3-104.9 months), and the median overall survival (OS) was 13.1 months in patients with EF. A total of 1,158 radiomics features were extracted, and eight radiomics features were selected for inclusion into a model for predicting EF, with an area under the receiver operating characteristic curve (AUC) value of 0.794. Multivariate analysis showed that tumor length, tumor volume, T stage, lymphocyte rate (LR), and grade IV esophagus stenosis were related to EF, and the AUC value of clinical model for predicting EF was 0.849. The clinical-radiomics model had the best performance in predicting EF with an AUC value of 0.896.

Conclusions

The clinical-radiomics nomogram can predict the risk of EF in ESCC patients and is helpful for the individualized treatment of EC.

Palliative management of a malignant tracheoesophageal fistula using repeat endobronchial laser debridement and esophageal stenting

A 71-year-old female presented with progressive dysphagia and unexplained weight loss. Computed tomography and esophagogastroduodenoscopy (EGD) revealed invasive esophageal squamous cell carcinoma, which was initially treated with local radiation and esophageal stenting. Over the next year, the patient experienced multiple symptoms and hospital admissions consistent with a malignant tracheoesophageal fistula, despite negative findings on imaging, bronchoscopy, and EGD. Prophylactic antibiotics were initiated based on symptomatology to prevent septic episodes. Stent erosion into the membranous trachea was eventually observed. Neodymium-yttrium-aluminum-garnet laser bronchoscopy was used periodically to debulk the invading tumor around the stent. A percutaneous endoscopic gastrostomy tube was also inserted to facilitate enteral nutrition and avoid aspiration pneumonia. The patient reported significant improvements in respiratory symptoms following each laser debridement and has progressed well beyond the life expectancy associated with malignant tracheoesophageal fistula.

Risk factors for aortoesophageal fistula in cT4b esophageal squamous cell carcinoma after definitive radiation therapy

Background

Esophageal fistula (EF) is a serious complication in patients with cT4b esophageal squamous cell carcinoma (ESCC) with adjacent organ involvement. Among EFs, aortoesophageal fistula (AEF), forming a fistula with the aorta, could be fatal. This study aimed to identify the risk factors for AEF in patients with cT4b ESCC with obvious or suspected aortic invasion who underwent definitive radiotherapy (DRT).

Methods

Forty-four patients with cT4b ESCC with obvious or suspected invasion to the aorta who underwent DRT were included. Blood tests and computed tomography (CT) findings before and after DRT were compared between the patients with and without AEF to identify the potential risk factors for AEF.

Results

Nine patients (20.5%) developed AEF after DRT. Comparing between patients with and without AEF, pre-DRT white blood cell counts and post-DRT C-reactive protein (CRP) levels were significantly higher in patients with AEF. Furthermore, pre-DRT CT findings were similar between the two groups. However, post-DRT CT findings demonstrated significantly larger picus angle and lower esophageal wall thickness on the aortic side in patients with AEF. Multivariate analysis identified elevated post-DRT CRP levels [<3.3 versus ≥3.3 mg/dL; odds ratio (OR): 30.7; 95% confidence interval (CI): 2.92-323.2; P=0.004] and esophageal wall thinning on post-DRT CT scans (>6 versus ≤6 mm; OR: 13.2; 95% CI: 1.24-140.1; P=0.033) as risk factors for AEF.

Conclusions

We found that post-DRT esophageal wall thinning on the aortic side, as observed on CT scans, and elevated CRP levels were predictive factors for AEF in patients with cT4b ESCC with obvious or suspected invasion to the aorta.

Retrospective cohort study on treatment modalities and survival time after oesophageal fistula in patients with oesophageal cancer in a regional cancer care centre in China

BACKGROUND

Oesophageal fistula (perforation) is a devastating complication in patients with oesophageal cancer . The optimal treatment remains uncertain.

OBJECTIVE

We sought to present real-world evidence on treatment modalities and survival postfistula in patients with oesophageal cancer.

DESIGN, SETTINGS AND MAIN OUTCOMES

This was a retrospective cohort study of patients with oesophageal cancer with oesophageal fistulae diagnosed between June 2010 and June 2020 in a regional cancer care centre in Zhengzhou, China (n=352). The treatment options included surgical resection, oesophageal stent grafting, gastrostomy, nasogastric tube and conservative care. The primary outcome was survival time (months) postfistula. Inverse probability of treatment weighting (IPTW) life regression was used to estimate the differences in survival time accounting for potential confounders.

RESULTS

The median survival time was 2.3 months (IQR: 0.7-6.0 months). Survival times were shorter in patients of male sex, T4 stage and oesophagotracheal versus oesophageal-mediastinal fistulae, and longer for any treatment option versus conservative care. The IPTW life regression analyses showed that in patients with oesophagotracheal fistulae, survival times were longer for stent grafting (+0.90 (95% CI 0.60 to 1.19) months) or gastrostomy (+0.81 (95% CI 0.47 to 1.13) months) versus nasogastric tube. In patients with oesophageal-mediastinal fistulae, survival times were shorter for stent grafting versus nasogastric tube (-0.36 (95% CI -0.63 to -0.09) months) and gastric tube (-0.29 (95% CI -0.50 to -0.08) months). Surgical resection was recorded in nine patients with oesophageal-mediastinal fistulae, and it was associated with the longest survival time in these patients.

CONCLUSIONS

Stent grafting or gastrostomy may be preferable to nasogastric tube in survival prognosis for patients with oesophageal cancer with oesophagotracheal fistulae. In contrast, stent grafting may be not preferable to nasogastric tube or gastrostomy in survival prognosis for patients with oesophageal-mediastinal fistulae.

Treatment mode and prognosis of esophageal perforation after radiotherapy in patients with esophageal carcinoma

Objective

Retrospectively analyzed the esophageal carcinoma (EC) patients with esophageal perforation (EP) after radiotherapy to discuss the treatment and prognosis.

Methods

Data of patients with EC who had EP after radiotherapy in Hebei Cancer Hospital were collected from 2001 to 2020 and retrospectively analyzed. All analyses were performed using SPSS Statistics for Windows, version 18. 0 (SPSS Inc., Chicago, Ill., USA). P values less than 0.05 were considered statistically significant.

Results

A total of 94 patients with EC were enrolled, among which 72 were males and 22 were females, with a median age of 62 (38-82) years. The tumor was located in the upper thoracic in 45 patients, middle thoracic in 45 patients, and lower thoracic in 4 patients. There were 30 cases of tracheoesophageal fistula (TEF) and 64 cases of esophagomediastinal fistula (EMF). All patients died within 11 months (median: two months) after EP. After EP, 48 patients were treated by tube feeding (include nasal feeding and gastrostomy), 26 patients by esophageal stenting, and 20 patients by fluid infusion therapy, and their one, three, and six months survival rates after EP were 81.3%, 31.3%, and 12.5% (P = 0.000). In the TEF group, the one, three, and six month survival rates after EP of tube feeding, esophageal stenting and fluid infusion groups were 88.2%, 17.6%, 11.8%; 45.5%, 27.3%, 0%; and 50.0%, 50.0%, 0% (P = 0.345). In the EMF group, the one, three, and six months survival rates after EP of this three groups were 77.4%, 38.7%, 12.9%; 26.7%, 20.0%, 6.7%; and 22.2%, 11.1%, 0% (P=0.002), respectively.

Conclusion

Most patients with EP after radiotherapy died within six months, with low survival and poor prognosis. Tube feeding therapy can achieve relatively good survival, especially for patients with EMF. The survival of patients treated by tube feeding therapy is significantly better than the survival of those treated by other methods.

Quantitative CT analysis to predict esophageal fistula in patients with advanced esophageal cancer treated by chemotherapy or chemoradiotherapy

Background

Esophageal fistula is one of the most serious complications of chemotherapy or chemoradiotherapy (CRT) for advanced esophageal cancer. This study aimed to evaluate the performance of quantitative computed tomography (CT) analysis and to establish a practical imaging model for predicting esophageal fistula in esophageal cancer patients treated with chemotherapy or chemoradiotherapy.

Methods

This study retrospectively enrolled 204 esophageal cancer patients (54 patients with fistula, 150 patients without fistula) and all patients were allocated to the primary and validation cohorts according to the time of inclusion in a 1:1 ratio. Ulcer depth, tumor thickness and length, and minimum and maximum enhanced CT values of esophageal cancer were measured in pretreatment CT imaging. Logistic regression analysis was used to evaluate the associations of CT quantitative measurements with esophageal fistula. Receiver operating characteristic curve (ROC) analysis was also used.

Results

Logistic regression analysis showed that independent predictors of esophageal fistula included tumor thickness [odds ratio (OR) = 1.167; p = 0.037], the ratio of ulcer depth to adjacent tumor thickness (OR = 164.947; p < 0.001), and the ratio of minimum to maximum enhanced CT value (OR = 0.006; p = 0.039) in the primary cohort at baseline CT imaging. These predictors were used to establish a predictive model for predicting esophageal fistula, with areas under the receiver operating characteristic curves (AUCs) of 0.946 and 0.841 in the primary and validation cohorts, respectively. The quantitative analysis combined with T stage for predicting esophageal fistula had AUCs of 0.953 and 0.917 in primary and validation cohorts, respectively.

Conclusion

Quantitative pretreatment CT analysis has excellent performance for predicting fistula formation in esophageal cancer patients who treated by chemotherapy or chemoradiotherapy.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40644-022-00490-2.

Risk factors and prognosis for esophageal fistula in patients with esophageal squamous cell carcinoma during radiotherapy

PURPOSE

To determine risk factors, treatment outcomes, and prognostic factors for esophageal fistula (EF) in patients with esophageal squamous cell carcinoma (ESCC) during radiotherapy.

METHODS

Between 2010 and 2018, 109 patients with EF during radiotherapy were retrospectively collected. A controlled cohort including 416 patients who received definitive chemoradiotherapy without EF was used to compare risk factors and survival outcomes. Univariate and multivariate logistic regression analyses were performed to identify predictors of EF. Propensity score matching (PSM) was applied to adjust for potential confounding factors.

RESULTS

Multivariate analysis demonstrated that sex, body mass index, alcohol history, esophageal ulceration, primary tumor length, T stage, and absolute lymphocyte count were independent risk factors for EF. After PSM, patients with EF showed remarkably worse prognosis than those without EF (median overall survival: 13.0 versus 20.5 months; P = 0.009). For patients with EF, serum albumin level (≥ 35 g/L), subsequent radiotherapy, and fistula closure were associated with significantly prolonged survival. In addition, esophageal-mediastinum fistula and subsequent radiotherapy were positive predictors for fistula closure.

CONCLUSIONS

We identified risk factors for radiotherapy-related EF and its unfavorable prognosis in patients with ESCC. Of them, patients with serum albumin level of ≥ 35 g/L, subsequent radiotherapy after EF, and fistula closure had a more favorable survival.

Efficacy and safety of radiotherapy/chemoradiotherapy combined with immune checkpoint inhibitors for locally advanced stages of esophageal cancer: A systematic review and meta-analysis

Background

Radiotherapy (RT)/Chemoradiotherapy (CRT) are important treatments for all stages of esophageal cancer (EC). The combination of immune checkpoint inhibitors (ICIs) with RT/CRT seems to be promising avenue for the treatment of EC. Therefore, a systematic review and meta-analysis was performed in order to assess the safety and efficacy of RT/CRT and ICI combination therapy for EC patients.

Methods

PubMed and several other databases were searched (according to specific criteria) to find relevant studies published prior to the 31st of December 2021.

Results

1962 articles were identified for screening, and six trials containing 668 patients were identified and pooled to determine the one- and two-year overall survival (OS), which were 84.5% (95% confidence interval (CI): 69.9%-100%) and 68.3% (95% CI: 49.0%-95.1%), respectively. Additionally, the rate of pooled grade 3-5 adverse reactions was 41.0% (95% CI: 31.2%-51.2%). The rate of specific grade 3-5 adverse reactions are as follows: lymphopenia (36.8%-60%), esophagitis (20%), anastomotic leakage (18%), esophageal fistula (10%), pain (10%), leukopenia (5.3%-10%), esophageal hemorrhage (2.5%-5%), chyle leakage (3%), fatigue (5%), cough (2.7%-5%), diarrhea (2.7%), pulmonary embolism (2.5%) and allergic reaction (2.5%). The pooled rate of pneumonitis of grade 3-5 and grade 1-5 was 0.8% (95% CI: 0.1%-0.16%, I2: 0%) and 5.4% (95% CI: 2.0%-14.2%, I2: 82%). For thoracic complication, esophagitis was 63.6% (95% CI: 42.4%-80.6%), which appeared to be more frequent with the combination of ICIs to RT/CRT (12%-37.7%). Other thoracic complications include esophageal hemorrhage (2.5%-10%), esophageal fistula (6%-10%) and anastomotic leakage (6%-21%). Additionally, some of the trials did not report cardiac related adverse reactions. The subgroup analyses also revealed that the pooled rate patients with grade 3-5 pneumonitis was higher for CRT/RT with concurrent and sequential ICI treatment (1.9%) than other groups (0.8%).

Conclusion

This study suggests that the addition of ICIs to RT/CRT for EC patients may be both safe and feasible. However, larger randomized studies are needed to confirm these results.

Incorporation of PET Metabolic Parameters With Clinical Features Into a Predictive Model for Radiotherapy-Related Esophageal Fistula in Esophageal Squamous Cell Carcinoma

Purpose

To determine whether the addition of metabolic parameters from fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) scans to clinical factors could improve risk prediction models for radiotherapy-related esophageal fistula (EF) in esophageal squamous cell carcinoma (ESCC).

Methods and Materials

Anonymized data from 185 ESCC patients (20 radiotherapy-related EF-positive cases) were collected, including pre-therapy PET/CT scans and EF status. In total, 29 clinical features and 15 metabolic parameters from PET/CT were included in the analysis, and a least absolute shrinkage and selection operator logistic regression model was used to construct a risk score (RS) system. The predictive capabilities of the models were compared using receiver operating characteristic (ROC) curves.

Results

In univariate analysis, metabolic tumor volume (MTV)_40% was a risk factor for radiotherapy (RT)-related EF, with an odds ratio (OR) of 1.036 [95% confidence interval (CI): 1.009–1.063, p = 0.007]. However, it was excluded from the predictive model using multivariate logistic regression. Predictive models were built based on the clinical features in the training cohort. The model included diabetes, tumor length and thickness, adjuvant chemotherapy, eosinophil count, and monocyte-to-lymphocyte ratio. The RS was defined as follows: 0.2832 − (7.1369 × diabetes) + (1.4304 × tumor length) + (2.1409 × tumor thickness) – [8.3967 × adjuvant chemotherapy (ACT)] − (28.7671 × eosinophils) + (8.2213 × MLR). The cutoff of RS was set at −1.415, with an area under the curve (AUC) of 0.977 (95% CI: 0.9536–1), a specificity of 0.929, and a sensitivity of 1. Analysis in the testing cohort showed a lower AUC of 0.795 (95% CI: 0.577–1), a specificity of 0.925, and a sensitivity of 0.714. Delong’s test for two correlated ROC curves showed no significant difference between the training and testing sets (p = 0.109).

Conclusions

MTV_40% was a risk factor for RT-related EF in univariate analysis and was screened out using multivariate logistic regression. A model with clinical features can predict RT-related EF.

Management of Esophageal Cancer-Associated Respiratory–Digestive Tract Fistulas

Respiratory–digestive tract fistulas are fatal complications that occur in esophageal cancer treatment. Interdisciplinary treatment strategies are still evolving, especially in anatomical treatment stratification. Thus, this study aims to evaluate general therapeutic strategies for this rare condition. Medical records were reviewed for esophageal cancer-associated respiratory–digestive tract fistula patients treated between January 2008 and September 2021. Fistulas were classified according to being surgery- and tumor-associated. Treatment strategies, clinical success, and survival were analyzed. A total of 51 patients were identified: 28 had tumor-associated fistulas and 23 surgery-associated fistulas. Risk factors for fistula development such as radiation (OR = 0.290, p = 0.64) or stent implantation (OR = 1.917, p = 0.84) did not correlate with lack of symptom control for RDF patients. In contrast, advanced lymph node metastasis as another risk factor was associated with persistent symptoms after treatment for RDF patients (OR = 0.611, p = 0.01). Clinical success significantly correlated with bilateral fistula repair in surgery-associated fistulas (p = 0.01), while tumor-associated fistulas benefited the most from non-surgical (p = 0.04) or combined surgical and non-surgical intervention (p = 0.04) and a bilateral fistula repair (p = 0.02) in terms of overall survival. The therapeutic strategy should aim for bilateral fistula closure. A multidisciplinary, stepwise approach might have the best chance for restoration or symptom control with optimized overall survival in selected patients.

Risk factors of esophageal fistula induced by re-radiotherapy for recurrent esophageal cancer with local primary site

PURPOSE

The purpose of the present study was to investigate risk factors for esophageal fistula (EF) in patients with recurrent esophageal cancer receiving re-radiotherapy with or without chemotherapy.

METHODS

We reviewed retrospectively the clinical characters and dosimetric parameters of 96 patients with recurrent esophageal cancer treated with re-radiotherapy in Cancer Hospital Affiliated to Shandong First Medical University between August 2014 and January 2021.Univariate and multivariate logistic regression analyses were provided to determine the risk factors of EF induced by re-radiotherapy.

RESULTS

The median time interval between two radiotherapy was 23.35 months (range, 4.30 to 238.10 months). EF occurred in 19 patients (19.79%). In univariate analysis, age, T stage, the biologically equivalent dose in the re-radiotherapy, total biologically equivalent dose, hyperfractionated radiotherapy, ulcerative esophageal cancer, the length of tumor and the maximum thickness of tumor had a correlation with the prevalence of EF. In addition, age (HR = 0.170, 95%CI 0.030-0.951, p = 0.044), T stage (HR = 8.369, 95%CI 1.729-40.522, p = 0.008), ulcerative esophageal cancer (HR = 5.810, 95%CI 1.316-25.650, p = 0.020) and the maximum thickness of tumor (HR = 1.314, 95%CI 1.098-1.572, p = 0.003) were risk factors of EF in multivariate logistic regression analysis.

CONCLUSIONS

The incidence of EF was significantly increased in patients with recurrent esophageal cancer who underwent re-radiotherapy. This study revealed that age, T stage, ulcerative esophageal cancer and the maximum thickness of the tumor were risk factors associated with EF. In clinical work, patients with risk factors for EF ought to be highly concerned and individualized treatment plans should be taken to reduce the occurrence of EF.

Addition of camrelizumab to docetaxel, cisplatin, and radiation therapy in patients with locally advanced esophageal squamous cell carcinoma: a phase 1b study

Patients with locally advanced esophageal squamous cell carcinoma (ESCC) show poor survival after concurrent chemoradiotherapy. This study investigated the safety and feasibility of combining concurrent chemoradiotherapy with the anti-PD-1 antibody camrelizumab as first-line treatment for these patients. In this phase 1b study (ClinicalTrials.gov NCT03671265), patients received concurrent chemotherapy (cisplatin [25 mg/m²] plus docetaxel [25 mg/m²] for 4 weeks) and radiotherapy (2.0 Gy/fraction, total 60 Gy) with camrelizumab (200 mg every 2 weeks for 32 weeks). Primary endpoints were safety and tolerability, and health-related quality of life. Secondary endpoints were radiological and pathological response rates, overall survival (OS), and progression-free survival (PFS). Candidate biomarkers in tumor and peripheral blood were monitored at baseline and after 40 Gy radiation. Twenty patients were enrolled. The most common treatment-related grade 3 adverse events included radiation esophagitis (20%) and esophageal fistula (10%). Serious treatment-related adverse events occurred in eight (40%) patients. No treatment-related deaths were reported. Health-related quality of life did not deteriorate. Thirteen (65%) patients had an objective response after 40 Gy radiation. At a median follow-up of 23.7 months (95% CI 21.9–24.5), OS and PFS time ranged from 8.2–28.5 and 4.0–28.5 months, respectively. The 12-month and 24-month OS rate was 85.0% and 69.6%; PFS rate was 80.0% and 65.0%. Tumor PD-L1 expression and CD11c⁺ dendritic cells and peripheral-blood IL-27, IL-15, Eotaxin-3, and IL-22 were associated with OS. First-line concurrent chemoradiotherapy plus camrelizumab had a manageable safety profile and promising antitumour efficacy for ESCC, and deserves further study.

Unrecognized digestive toxicities of radiation therapy

The aim of this article is to review unrecognized toxicities resulting from radiation therapy of digestive neoplasms. Due to their precocious occurrence, acute toxicities are well-known by radiation oncologist, and their treatment well-established. Thus, acute toxicities will not be described in this review. We will focus on incidence, diagnosis, and management of late and uncommon toxicities occurring in the digestive tract and digestive organs. Prevention, by respecting healthy tissues constraints, is the main tool to reduce incidence of those rare complications. Nonetheless, once installed, late toxicities remain a major burden in terms of quality of life and can even be life threatening. Hence, information and education about their diagnosis and management is important.

High incidence of esophageal fistula on patients with clinical T4b esophageal squamous cell carcinoma who received chemoradiotherapy: A retrospective analysis

BACKGROUND AND PURPOSE

Despite definitive chemoradiotherapy (CRT) being a recommended therapeutic method for patients with T4b esophageal squamous cell carcinoma (ESCC), treatment response and complications remain unclear. Esophageal fistula is a severe CRT-related complication when treating locally advanced ESCC, but data on risk factors that lead to esophageal fistula formation are limited. The aim of this analysis is to characterize the outcomes of T4b ESCC treated by CRT and investigate the risk factors of esophageal fistula.

MATERIALS AND METHODS

We retrospectively analyzed 136 patients with clinically unresectable T4b ESCC who were treated with CRT. Response, survival, and complication rates, particularly the rate of esophageal fistula and its associated risk factors were analyzed.

RESULTS

The median progression-free survival and overall survival (OS) of all patients were 7.9 (95% confidence interval [CI]: 6.1-9.7) and 12.2 months (95% [CI]: 8.9-15.4), respectively. The Kaplan-Meier curves showed that the 3- and 5-year OS rates were 29.9% and 20.2%, respectively. The incidence rate of esophageal fistulas was 30.1%. The median OS for patients with esophageal fistula was only 6.9 (95%[CI] = 6.0-7.8) months. The risk for developing esophageal fistulas was significantly high for ulcerative-type tumors (odds ratio [OR] = 3.202; 95%[CI] = 1.036-7.850, P = 0.011) and for those invading the bronchus/trachea (OR = 3.378; 95%[CI] = 1.223-9.332, P = 0.048).

CONCLUSION

We demonstrated that CRT for T4b ESCC patients has a curative potential, despite a high incidence of esophageal fistula, which was the main cause of treatment failure. The higher risk for fistula formation were tumors with ulceration or bronchus/trachea invasion.