Radiotherapy for esophageal carcinoma: dose, response and survival

Downregulation of Claudin5 promotes malignant progression and radioresistance through Beclin1-mediated autophagy in esophageal squamous cell carcinoma

BACKGROUND

Esophageal squamous cell carcinoma (ESCC) is a highly prevalent and aggressive cancer with poor treatment outcomes. Despite the critical role of tight junction proteins in tumorigenesis, the involvement of Claudin5 in ESCC remains poorly understood. Thus, this study aimed to investigate the role of Claudin5 in ESCC malignant progression and radioresistance, as well as the underlying regulatory mechanisms.

METHODS

The expression of Claudin5 was evaluated in esophageal cancer tissue using both public databases and 123 clinical samples. CCK-8, transwell invasion, wound healing and clonogenic survival assays were used to examine the proliferation, invasion, migration and radiosensitivity of ESCC cells in vitro. Xenograft and animal lung metastasis experiments were conducted to examine the impact of Claudin5 on tumor growth and lung metastasis in vivo. The effect of Claudin5 on autophagy was detected via transmission electron microscopy, western blotting and autophagy flux. Immunohistochemical staining was used to detect Claudin5 expression in ESCC patient samples. The statistical difference was assessed with Student t test or one-way ANOVA. The correlation between Claudin5 expression and radiotherapy response rate was performed by the Chi-square test. The significance of Kaplan-Meier curves was evaluated by the Logrank test.

RESULTS

Claudin5 expression was downregulated in ESCC tissues. Downregulation of Claudin5 promoted ESCC cell proliferation, invasion, and migration both in vitro and in vivo. Downregulation of Claudin5 decreased the radiosensitivity of ESCC cells. Moreover, downregulation of Claudin5 promoted autophagy and the expression of Beclin1. Beclin1 knockdown reversed the effect of Claudin5 downregulation on autophagy induction and the promotion of ESCC cell malignant progression and radioresistance. Additionally, low expression of Claudin5 in ESCC cancer tissues was associated with poor radiotherapy response and prognosis.

CONCLUSIONS

In summary, these findings suggest that downregulation of Claudin5 promotes ESCC malignant progression and radioresistance via Beclin1-autophagy activation and may serve as a promising biomarker for predicting radiotherapy response and patient outcome in ESCC.

Dosimetric analysis and biological evaluation between proton radiotherapy and photon radiotherapy for the long target of total esophageal squamous cell carcinoma

Objective

The purpose of this study is to compare the dosimetric and biological evaluation differences between photon and proton radiation therapy.

Methods

Thirty esophageal squamous cell carcinoma (ESCC) patients were generated for volumetric modulated arc therapy (VMAT) planning and intensity-modulated proton therapy (IMPT) planning to compare with intensity-modulated radiation therapy (IMRT) planning. According to dose–volume histogram (DVH), dose–volume parameters of the plan target volume (PTV) and homogeneity index (HI), conformity index (CI), and gradient index (GI) were used to analyze the differences between the various plans. For the organs at risk (OARS), dosimetric parameters were compared. Tumor control probability (TCP) and normal tissue complication probability (NTCP) was also used to evaluate the biological effectiveness of different plannings.

Results

CI, HI, and GI of IMPT planning were significantly superior in the three types of planning (p < 0.001, p < 0.001, and p < 0.001, respectively). Compared to IMRT and VMAT planning, IMPT planning improved the TCP (p<0.001, p<0.001, respectively). As for OARs, IMPT reduced the bilateral lung and heart accepted irradiation dose and volume. The dosimetric parameters, such as mean lung dose (MLD), mean heart dose (MHD), V₅, V₁₀, and V₂₀, were significantly lower than IMRT or VMAT. IMPT afforded a lower maximum dose (D_max) of the spinal cord than the other two-photon plans. What’s more, the radiation pneumonia of the left lung, which was caused by IMPT, was lower than IMRT and VMAT. IMPT achieved the pericarditis probability of heart is only 1.73% ± 0.24%. For spinal cord myelitis necrosis, there was no significant difference between the three different technologies.

Conclusion

Proton radiotherapy is an effective technology to relieve esophageal cancer, which could improve the TCP and spare the heart, lungs, and spinal cord. Our study provides a prediction of radiotherapy outcomes and further guides the individual treatment.

Identification of Immune Subtypes of Esophageal Adenocarcinoma to Predict Prognosis and Immunotherapy Response

A low response rate limits the application of immune checkpoint inhibitors (ICIs) in the treatment of esophageal adenocarcinoma (EAC), which requires the precise characterization of heterogeneous tumor microenvironments. This study aimed to identify the molecular features and tumor microenvironment compositions of EAC to facilitate patient stratification and provide novel strategies to improve clinical outcomes. Here, we performed consensus molecular subtyping with nonnegative matrix factorization (NMF) using EAC data from the Cancer Genome Atlas (TCGA) and identified two distinct subtypes with significant prognostic differences and differences in tumor microenvironments. The findings were further validated in independent EAC cohorts and potential response to ICI therapy was estimated using Tumor Immune Dysfunction and Exclusion (TIDE) and SubMap methods. Our findings suggest that EAC patients of subtype 2 with low levels of cancer-associated fibroblasts, tumor associated macrophages (TAMs), and MDSCs in the tumor microenvironment may benefit from PD-1 blockade therapy, while patients of subtype 1 are more responsive to chemotherapy or combination therapy. These findings might improve our understanding of immunotherapy efficacy and be useful in the development of new strategies to better guide immunotherapy and targeted therapy in the treatment of EAC.

Pronounced Enhancement in Radiosensitization of Esophagus Cancer Cultivated in Docosahexaenoic Acid via the PPAR -γ Activation

Docosahexaenoic acid (DHA) has been reported to suppress the tumor growth and improve prognosis and has been used to cooperate with many other chemotherapy medicines. Up to now, surveys focused on the Interaction between DHA and radiation are relatively modest. Our study sought to evaluate the radiosensitivity changes caused by DHA on esophageal cancer cells. We selected TE-1 and TE-10 esophagus cancer cells as models and performed routine cell proliferation assay and cloning assay to detect the impact of DHA combined with X-ray. We used cell cycle assay, lipid peroxidation assay, comet assay, and apoptosis assay to unearth the potential causes. We also launched a mouse transplanted tumor experiment to verify the synergetic effect of DHA and irradiation. Finally, a western blot assay was used to find a novel mechanism. As a result, DHA improved TE-1 and TE-10 radiosensitivity in vivo and in vitro. What's more, PPAR-γ expression increased due to the DHA supplement. Inhibiting PPAR-γ could attenuate benefits brought out by DHA somehow. Due to its explicit usage and convenience, DHA would serve as an adjuvant therapy before radiotherapy if the clinical trials indicated positive.

Radioimmunotherapy for solid tumors: spotlight on Glypican-1 as a radioimmunotherapy target

Radioimmunotherapy (i.e., the use of radiolabeled tumor targeting antibodies) is an emerging approach for the diagnosis, therapy, and monitoring of solid tumors. Often using paired agents, each targeting the same tumor molecule, but labelled with an imaging or therapeutic isotope, radioimmunotherapy has achieved promising clinical results in relatively radio-resistant solid tumors such as prostate. Several approaches to optimize therapeutic efficacy, such as dose fractionation and personalized dosimetry, have seen clinical success. The clinical use and optimization of a radioimmunotherapy approach is, in part, influenced by the targeted tumor antigen, several of which have been proposed for different solid tumors. Glypican-1 (GPC-1) is a heparan sulfate proteoglycan that is expressed in a variety of solid tumors, but whose expression is restricted in normal adult tissue. Here, we discuss the preclinical and clinical evidence for the potential of GPC-1 as a radioimmunotherapy target. We describe the current treatment paradigm for several solid tumors expressing GPC-1 and suggest the potential clinical utility of a GPC-1 directed radioimmunotherapy for these tumors.

Immunotherapy for Esophageal Cancers: What Is Practice Changing in 2021?

The prognosis of advanced esophageal cancer is dismal, and treatment options are limited. Since the first promising data on second-line treatment with checkpoint inhibitors in esophageal cancer patients were published, immunotherapy was surmised to change the face of modern cancer treatment. Recently, several studies have found this to be true, as the checkpoint inhibitors nivolumab and pembrolizumab have achieved revolutionary response rates in advanced as well as resectable settings in esophageal cancer patients. Although the current results of large clinical trials promise high efficacy with tolerable toxicity, desirable survival rates, and sustained quality of life, some concerns remain. This review aims to summarize the novel clinical data on immunotherapeutic agents for esophageal cancer and provide a critical view of potential restrictions for the implementation of these therapies for unselected patient populations.

Modulation of Tumor Microenvironment to Enhance Radiotherapy Efficacy in Esophageal Squamous Cell Carcinoma by Inhibiting Carbonic Anhydrase IX

The radiotherapy outcomes of patients with advanced esophageal squamous cell carcinoma (ESCC) remain poor due to hypoxia. Carbonic anhydrase IX (CAIX) is a membrane-associated enzyme that induces hypoxia, extracellular acidity, and upregulation of hypoxia-related factors in tumor microenvironment, thereby promoting tumor metastasis. CAIX is upregulated in ESCC tissues compared to normal surrounding tissues. In the current study, we aimed to investigate the effect of CAIX inhibition on the modulation of tumor microenvironment and radiotherapy efficacy in ESCC. Higher CAIX expression was correlated with poorer progression-free survival in ESCC patients. Then, the ethyl N-(4-methylphenyl) sulfonylcarbamate (S4) was used to inhibit CAIX expression in ESCC cells and mice xenografts. The pretreatment of ESCC cells with S4 significantly downregulated CAIX expression, decreased intracellular pH, reduced cell viability, resulting in decreased oxygen consumption and more sensitive response to X-ray irradiation. In mice inoculated with ESCC cells, the combination of X-ray irradiation with S4 further improved survival, delayed tumor growth, decreased hypoxia level, exaggerated DNA damage, and increased apoptosis compared with the groups treated solely with S4 or radiotherapy. In conclusion, our study showed that the inhibition of CAIX by S4 treatment altered hypoxic tumor micro-environment, exaggerated DNA damage, increased apoptosis, and thus enhanced radiotherapy efficacy in ESCC. These findings provided a potential therapeutic strategy for patients with resistant ESCC.

A Canadian single institution real-world experience using the CROSS trial regimen in the treatment of Esophageal and Gastroesophageal Junction Carcinoma

BACKGROUND

Trimodality therapy using the CROSS trial protocol is an accepted standard of care for locally advanced esophageal and gastroesophageal junction cancers. For medically inoperable patients, chemoradiation (CRT) has been a therapeutic option. This single institution review aimed to assess the real-world application of the CROSS trial protocol.

METHODS

This is a retrospective review of 83 patients who underwent CRT with carboplatin and paclitaxel with trimodality or definitive intent between June 2012 and June 2018. 65 patients underwent neoadjuvant CRT (NCRT); 40 had surgery. 18 had definitive CRT (DCRT). Patients' demographics, clinical, pathological, treatment and surgical characteristics were assessed. The data was analyzed in exploratory analyses and Kaplan-Meier curves.

RESULTS

For the 83 patients, the following median values were seen: RT dose 50.4 Gy, chemotherapy doses 5, time from CRT to surgery 62 days. 23% NCRT and 72% DCRT patients were ≥ 75 yrs and 49%, and 33% of these respectively had no interruptions to CRT. Patients ≥75 yrs were more likely to have DCRT (p = 0.001). Patients who underwent surgery were younger (p = 0.04). For NCRT and surgery, NCRT only, and DCRT respectively, median overall survival was 35.5, 12.1 and 17.1 months (log rank p=0.008); progression free survival was 32.2, 10 and 9.6 months (log rank p=0.001).

CONCLUSIONS

Despite broadening of the CROSS trial eligibility criteria in our real-world data, there appears to be a survival benefit with trimodality therapy. The use of carboplatin and paclitaxel in DCRT may be of value and requires further study. This article is protected by copyright. All rights reserved.

Oral maintenance therapy using apatinib combined with S-1/capecitabine for esophageal squamous cell carcinoma with residual disease after definitive chemoradiotherapy

Background: A substantial number of patients with esophageal squamous cell carcinoma (ESCC) do not achieve complete remission after definitive concurrent chemoradiotherapy (dCRT). We performed this retrospective study to evaluate the efficacy and safety of apatinib combined with S-1/capecitabine as the oral maintenance therapy for these patients.

Methods: Thirty-nine ESCC patients with residual disease after dCRT were included. Patients were treated with apatinib combined with S-1 /capecitabine after dCRT. Efficacy, toxicity, and survival were analyzed.

Results: Of the 39 patients, 5 (12.8%) achieved a partial response and 29 (74.4%) achieved stable disease, yielding a disease control rate of 87.2%. The median progression-free survival (PFS) and overall survival (OS) were 27.5 (95%CI: 14.9 - 40.1) and 38.1 (95%CI: 31.3 - 44.8) months. Most frequent adverse events were of grade 1 to 2. Multivariate analysis revealed the occurrence of any adverse events (HR = 0.274, 95%[CI] = 0.119 - 0.630) correlated to better PFS and occurrence of proteinuria (HR = 0.108, 95%[CI] = 0.025 - 0.456) predicted better OS.

Conclusion: The oral combination therapy consisting of apatinib and S-1/capecitabine showed a tolerable toxicity profile and achieved satisfactory disease control in ESCC patients with residual disease after dCRT.

Cancer-Associated Fibroblast-Induced Resistance to Chemotherapy and Radiotherapy in Gastrointestinal Cancers

In the past few decades, the role of cancer-associated fibroblasts (CAFs) in resistance to therapies for gastrointestinal (GI) cancers has emerged. Clinical studies focusing on GI cancers have revealed that the high expression of CAF-related molecules within tumors is significantly correlated with unfavorable therapeutic outcomes; however, the exact mechanisms whereby CAFs enhance resistance to chemotherapy and radiotherapy in GI cancers remain unclear. The cells of origin of CAFs in GI cancers include normal resident fibroblasts, mesenchymal stem cells, endothelial cells, pericytes, and even epithelial cells. CAFs accumulated within GI cancers produce cytokines, chemokines, and growth factors involved in resistance to therapies. CAF-derived exosomes can be engaged in stroma-related resistance to treatments, and several non-coding RNAs, such as miR-92a, miR-106b, CCAL, and H19, are present in CAF-derived exosomes and transferred to GI cancer cells. The CAF-induced desmoplastic reaction interferes with drug delivery to GI cancer cells, evoking resistance to chemotherapy. However, due to the heterogeneity of CAFs in GI cancers, identifying the exact mechanism underlying CAF-induced resistance may be difficult. Recent advancements in single-cell "omics" technologies could offer clues for revealing the specific subtypes and biomarkers related to resistance.

Dose escalation of 3D radiotherapy is effective for esophageal squamous cell carcinoma: a multicenter retrospective analysis (3JECROG R-03)

Background

To evaluate the impact of radiation dose escalation on overall survival (OS) in patients with non-metastatic esophageal squamous cell carcinoma (ESCC) treated with radical radiotherapy.

Methods

The clinical data of ESCC patients treated with three-dimensional (3D) radiotherapy alone or chemoradiotherapy were collected from multiple institutes and retrospectively analyzed. Patients who received radiation dose ≥40 Gy were included. Radiation dose as a continuous variable was entered into the Cox regression model by using penalized spline regression to allow for a nonlinear relationship between radiation dose and OS to be identified. Patients were stratified into five groups according to EQD₂. The Kaplan-Meier method was used to assess the OS in different dose groups. Univariate and multivariate analyses were performed to evaluate the factors associated with OS.

Results

A total of 2,469 patients were included from 10 institutes across China. The median follow-up time was 58.3 months [95% confidence interval (CI): 56.4–60.2 months]. The median OS and PFS time were 24.3 months (95% CI: 22.5–26.2 months) and 18.0 months (95% CI: 16.4–19.6 months), respectively. The risk of death decreased sharply with a dose up to 60 to 62 Gy, before increasing slightly after the dose was elevated beyond 62 Gy. Multivariate analysis indicated that the chance of death was significantly decreased in patients who received radiotherapy doses of 60–62 Gy [P=0.028, hazard ratio (HR) 0.85, 95% CI: 0.73–0.98)], compared with those who received radiotherapy doses of 40–60 Gy.

Conclusions

Our results reveal radiation dose is a significant prognostic factor of survival for ESCC patients. Higher radiation dose contributes to much more favorable survival outcomes for ESCC patients receiving radical radiotherapy by modern techniques, and 60 Gy or above might be the most optimal radiation dose.

GPR120 promotes radiation resistance in esophageal cancer via regulating AKT and apoptosis pathway

The aim of the study is to investigate the role of GPR120 on the biological behavior of esophageal cancer cells in the setting of radiation and explore the mechanism. GPR120 knockdown was fulfilled by siRNA-mediated effects in two esophageal cancer cell lines Eca109 and EC9706. Colony formation, survival fraction calculation, viable cell evaluation by cell counting kit-8 assay and cell apoptosis analysis by phycoerythrin annexin V and 7-amino-actinomycin (7-AAD) staining and the flow cytometry examination was evaluated in Eca109 and EC9706 under the treatment of different radiation dosage. The mechanisms were explored by the evaluation of the Akt pathway and apoptosis protein level. Significantly decreased GPR120 mRNA and protein after GPR120 siRNA treatment compared to control siRNA treatment. Significantly decreased colony formation was found in GPR120 siRNA-treated Eca109 and EC9706 cells compared to control siRNA-treated cells at the radiation dosage of 2, 4, 6 and 8 Gy. Moreover, decreased survival fraction number with increased sensitive enhancing ratio was also found in GPR120 siRNA-treated Eca109 and EC9706 cells compared to control siRNA-treated cells. Decreased cell viability and increased cell apoptosis in GPR120 siRNA-treated esophageal cancer cells. GPR120 siRNA decreased the Akt phosphorylation and anti-apoptotic Bcl-2 expression level, but increased pro-apoptotic Bim expression level in esophageal cancer cell lines. GPR120 regulated the biological behavior of the esophageal cancer cells via affecting Akt pathway and apoptosis molecules. Moreover, GPR120 siRNA combined radiation treatment could be a therapeutic choice for esophageal cancer.

Nutritional assessment and risk factors associated to malnutrition in patients with esophageal cancer

INTRODUCTION

Esophageal cancer is the fourth most common cause of cancer death in China. Patients with esophageal cancer are more likely to suffer from malnutrition. The purpose of this study is to assess nutritional status of patients with esophageal cancer from multiple perspectives and analyze the risk factors.

METHODS

A total of 1482 esophageal cancer patients were enrolled in the study. We investigated the Scored Patient Generated Subjective Global Assessment (PG-SGA) scores, NRS-2002 scores, Karnofsky performance status scores, anthropometric, and laboratory indicators of patients. Unconditional logistic regression analysis was applied to identify the risk factors of nutritional status.

RESULTS

PG-SGA (≥4) and NRS-2002 (≥3) showed the incidence of malnutrition were 76% and 50%, respectively. In the patients with PG-SGA score ≥4, the proportion of patients who did not receive any nutritional support was 60%. The incidence of malnutrition in females was significantly higher than that in males. Besides, abnormality rates of Red blood cell (P < 0.001), MAC (P = 0.037), and MAMC (P < 0.001) in males was significantly higher than that in females, while abnormality rates of TSF (P < 0.001) was lower than that in females. After adjusted with the other potential risk factors listed, unconditional logistic regression analysis indicated smoking (odds ratio: 2.868, 95% confidence interval: 1.660-4.954), drinking (OR: 1.726, 95% CI: 1.099-2.712), family history (OR: 1.840, 95% CI: 1.132-2.992), radiotherapy or chemotherapy (OR: 1.594, 95% CI: 1.065-2.387), and pathological stage (OR: 2.263, 95% CI: 1.084-4.726) might be the risk factors of nutritional status, while nutritional support can reduce the risk of malnutrition.

CONCLUSION

Effective nutritional risk assessment methods and nutritional intervention measures can be adopted according to the research data to improve quality of life of esophageal cancer patients.

Definitive radiochemotherapy in esophageal cancer - a single institution experience

Background

Definitive radiochemotherapy is the preferred treatment option in patients with the cancer of the cervical esophagus and a viable treatment option in patients with the cancer of lower two thirds of the esophagus, who decline proposed surgical treatment. The purpose of the study was to evaluate the treatment results with definitive radiochemotherapy of patients with esophageal cancer, treated in a single institution in the period from 2010 to 2017.

Patients and methods

All available medical data for 55 patients with esophageal cancer, who were treated with definitive radiochemotherapy with curative intent, were analyzed retrospectively. Patients were irradiated to a total dose to the tumor of 70 Gy (2 Gy per fraction) in upper third (cervical) tumors or to the mean total dose of 57.6 Gy (1.8 Gy per fraction) in middle third (intrathoracic) tumors. All but one patient received concomitant chemotherapy, with the majority of them (41 patients; 74.5%) receiving concomitant chemotherapy with 5-fluorouracil in continuous 96 hours infusion and cisplatin. The main endpoints of the study were overall survival (OS; death of any cause), locoregional control (LRC; local and/or regional disease recurrence) and disease-free survival (DFS; recurrence of any kind and/or new primary malignoma). Univariate analysis testing the impact of different parameters on survivals and analysis of treatment related side effects were performed as well.

Results

The mean age of patients was 62 years (SD 9 years; range: 29–80 years). Majority of them had squamous cell cancer (53 patients; 96.4%) in the stage T3 or T4 (47 patients; 85.5%) and/or N+ disease (35 patients; 63.6%). Median follow-up time for the whole group of patients was 16.8 months (range: 0.3–81.8 months). At the time of analysis 14 (25.5%) patients were still alive. Rates for OS, LRC and DFS at two and five years were as follows: 47% and 19.4%; 43.7% and 41%; 32.1% and 11.5%, respectively.

Conclusions

The study results of treatment with definitive radiochemotherapy in patients with esophageal cancer are similar to the results of other studies. Majority of patients ended the treatment according to the protocol, which at least in part can be attributed to the adequate and well organized supportive treatment in our institution.

The Critical Role of Hypoxic Microenvironment and Epigenetic Deregulation in Esophageal Cancer Radioresistance

Esophageal cancer (EC) is the seventh most common cancer worldwide and the sixth leading cause of death, according to Globocan 2018. Despite efforts made for therapeutic advances, EC remains highly lethal, portending a five-year overall survival of just 15-20%. Hence, the discovery of new molecular targets that might improve therapeutic efficacy is urgently needed. Due to high proliferative rates and also the limited oxygen and nutrient diffusion in tumors, the development of hypoxic regions and consequent activation of hypoxia-inducible factors (HIFs) are a common characteristic of solid tumors, including EC. Accordingly, HIF-1α, involved in cell cycle deregulation, apoptosis, angiogenesis induction and proliferation in cancer, constitutes a predictive marker of resistance to radiotherapy (RT). Deregulation of epigenetic mechanisms, including aberrant DNA methylation and histone modifications, have emerged as critical factors in cancer development and progression. Recently, interactions between epigenetic enzymes and HIF-1α transcription factors have been reported. Thus, further insight into hypoxia-induced epigenetic alterations in EC may allow the identification of novel therapeutic targets and predictive biomarkers, impacting on patient survival and quality of life.

Prediction of response after chemoradiation for esophageal cancer using a combination of dosimetry and CT radiomics

PURPOSE

To investigate the treatment response prediction feasibility and accuracy of an integrated model combining computed tomography (CT) radiomic features and dosimetric parameters for patients with esophageal cancer (EC) who underwent concurrent chemoradiation (CRT) using machine learning.

METHODS

The radiomic features and dosimetric parameters of 94 EC patients were extracted and modeled using Support Vector Classification (SVM) and Extreme Gradient Boosting algorithm (XGBoost). The 94-sample dataset was randomly divided into a 70-sample training subset and a 24-sample independent test set while keeping the class proportions intact via stratification. A receiver operating characteristic (ROC) curve was used to assess the performance of models using radiomic features alone and using combined radiomic features and dosimetric parameters.

RESULTS

A total of 42 radiomic features and 18 dosimetric parameters plus the patients' characteristic parameters were extracted for these 94 cases (58 responders and 36 non-responders). XGBoost plus principal component analysis (PCA) achieved an accuracy and area under the curve of 0.708 and 0.541, respectively, for models with radiomic features combined with dosimetric parameters, and 0.689 and 0.479, respectively, for radiomic features alone. Image features of GlobalMean X.333.1, Coarseness, Skewness, and GlobalStd contributed most to the model. The dosimetric parameters of gross tumor volume (GTV) homogeneity index (HI), Cord Dmax, Prescription dose, Heart-Dmean, and Heart-V50 also had a strong contribution to the model.

CONCLUSIONS

The model with radiomic features combined with dosimetric parameters is promising and outperforms that with radiomic features alone in predicting the treatment response of patients with EC who underwent CRT.

KEY POINTS

• The model with radiomic features combined with dosimetric parameters is promising in predicting the treatment response of patients with EC who underwent CRT. • The model with radiomic features combined with dosimetric parameters (prediction accuracy of 0.708 and AUC of 0.689) outperforms that with radiomic features alone (best prediction accuracy of 0.625 and AUC of 0.412). • The image features of GlobalMean X.333.1, Coarseness, Skewness, and GlobalStd contributed most to the treatment response prediction model. The dosimetric parameters of GTV HI, Cord Dmax, Prescription dose, Heart-Dmean, and Heart-V50 also had a strong contribution to the model.

Three-dimensional conformal radiation therapy alone for esophageal squamous cell carcinoma: 10-year survival outcomes

Background

Concurrent chemoradiation is the standard treatment for locally advanced esophageal squamous cell carcinoma (SCC). We conducted a phase II study to explore the effect of three‐dimensional conformal radiotherapy (3‐DCRT) alone for patients with locally advanced esophageal SCC. This study aimed to analyze the long‐term survival outcomes.

Methods

Between November 2004 and April 2007, 30 patients with thoracic esophageal SCC underwent late‐course sequential boost 3‐DCRT at Fudan University Shanghai Cancer Center. The planning target volume (PTV1) comprised a 1.2–1.5 cm lateral margin around the gross tumor volume and a 3.0 cm margin, superior and inferior to the gross tumor volume. PTV2 encompassed the gross tumor volume with a margin of 0.5–0.7 cm. The PTV1 dose delivered was 50 Gy, and the PTV2 dose was a boost dose of 16 Gy, resulting in a total dose of 66 Gy. No chemotherapy was administered.

Results

The median follow‐up time was 30 months for all patients, and 132 months for patients who were alive. The median overall survival was 27 months (95% confidence interval [CI] 18.9–35.0). The 2‐, 5‐, and 10‐year overall survival rates were 56.6%, 33.3%, and 26.6%, respectively. The median progression‐free survival was 14 months (95% CI 7.7–20.2 months), and the 2‐, 5‐, and 10‐year progression‐free survival rates were 33.3%, 30.0%, and 26.6%, respectively. No severe late toxicity was observed in long‐term survivors.

Conclusion

Late‐course sequential boost 3‐DCRT is safe and feasible with promising long‐term outcomes for esophageal SCC.

Radiotherapy improves the survival of patients with metastatic esophageal squamous cell carcinoma: a propensity score matched analysis of Surveillance, Epidemiology, and End Results database

The survival advantage of radiotherapy (RT) for patients with metastatic esophagus cancer has not been adequately evaluated. This study aims to find out the role of RT for metastatic esophagus cancer and to find the different effect for RT to esophageal adenocarcinoma (EAC) and esophageal squamous cell carcinoma (ESCC). This study included 5,970 metastatic esophagus cancer patients from the Surveillance, Epidemiology, and End Results (SEER) database, registered from January 2004 to December 2013. Propensity score (PS) analysis with 1:1 nearest neighbor matching method was used to ensure well-balanced characteristics of all comparison groups by histological types. The Kaplan-Meier and Cox proportional hazardous models were used to evaluate the overall survival (OS), cancer-specific survival (CSS), and corresponding 95% confidence interval (CI). Generally speaking, EAC did not get survival benefit from RT (median OS for RT group vs. no-RT group-8.0, 7.6-8.4 vs. 9.0, 8.5-9.5, P = 0.073), whereas RT for metastatic ESCC did significantly improve OS (median OS for RT group vs. no-RT group-8.0, 7.4-8.6 vs. 7.0, 6.4-7.6, P = 0.044). Therefore, compared with adenocarcinoma, ESCC could get more survival benefit from RT.

Downregulation of microRNA‑449a‑5p promotes esophageal squamous cell carcinoma cell proliferation via cyclin D1 regulation

Aberrant microRNA-449a (miR-449a-5p) expression has been demonstrated to be associated with the development of various cancer types. However, the effect of miR-449a-5p on esophageal squamous cell carcinoma (ESCC) cell proliferation remains unknown. The present study aimed to determine whether miR-449a-5p may regulate ESCC cell proliferation via negative regulation of cyclin D1. Reverse transcription quantitative-polymerase chain reaction was used to measure the expression of miR-449a-5p in ESCC tissues and cells. Western blot was performed to analyze the protein level of cyclin D1. The proliferation of ESCC cells was determined by MTT and clone formation assay. Paired ESCC and adjacent normal esophageal squamous tissues were collected from patients with ESCC. It was demonstrated that miR-449a-5p expression was reduced, whereas cyclin D1 expression was increased in ESCC tissues compared with adjacent normal tissues. Proliferation was investigated in vivo using the ESCC cell line Eca-190. miR-449a-5p inhibitor transfection facilitated the proliferation of Eca-109 cells. By contrast, transfection with miR-449a-5p mimics inhibited Eca-109 cell proliferation. Furthermore, it was confirmed that miR-449a-5p directly bound to the 3′-untranslated region of cyclin D1. Transfection with cyclin D1 small interfering RNA reversed the effects of the miR-449a-5p inhibitor on Eca-109 cell proliferation. In conclusion, miR-449a-5p may control ESCC proliferation through the negative regulation of cyclin D1 expression.