Comparative outcomes for three-dimensional conformal versus intensity-modulated radiation therapy for esophageal cancer

Comparative Outcomes and Toxicity in Patients With Esophageal Cancer After Trimodality Therapy With Step-and-Shoot Intensity-Modulated Radiation Therapy Versus Volumetric Modulated Arc Therapy: The MD Anderson Experience

AIMS

To evaluate outcomes and toxicity after intensity-modulated radiation therapy given as step-and-shoot (SS) or volumetric modulated arc therapy (VMAT) for patients with locally advanced esophageal cancer treated with trimodality therapy (i.e. neoadjuvant concurrent chemoradiation therapy followed by surgery).

MATERIALS AND METHODS

Patients consecutively treated with trimodality therapy including IMRT in 2001-2022 (n = 449) were retrospectively reviewed, and 106 pairs of propensity-matched SS and VMAT patients were identified. Survival, recurrence, surgery-related prognostic factors, and chemoradiation-related toxicities were evaluated between groups.

RESULTS

Baseline characteristics were balanced between both groups except for body mass index, history of other cancer, clinical disease stage, and use of induction chemotherapy. Median follow-up time was 40 months. Relative to SS, VMAT led to higher 3-year overall survival (OS; P = 0.028, hazard ratio [HR] 0.645, 95% confidence interval [CI] 0.436-0.954) but not progression-free, locoregional recurrence-free, or distant metastasis-free survival. No predictor of excellent OS by SS versus VMAT was identified in multivariable analyses. However, VMAT was associated with reduced odds of postoperative cardiac complications (P < 0.001, odds ratio [OR] 0.296, 95% CI 0.148-0.591), pulmonary complications (P = 0.048, OR 0.539, 95% CI 0.292-0.994), pathologic partial response or worse (≥10% viable cells; P = 0.003, OR 0.418, 95% CI 0.235-0.743), and positive/close margins (P = 0.023, OR 0.346, 95% CI 0.138-0.867) relative to SS. VMAT was also associated with reduced rates of chemoradiation therapy-related weight loss (33.0% versus 79.2%, P < 0.001), fatigue (40.6% versus 68.9%, P < 0.001), nausea (31.1% versus 58.5%, P < 0.001) and cardiac toxicity (0% versus 6.6%, P = 0.007) than SS.

CONCLUSION

Based on this single institution, retrospective study with a 40-month median follow-up, VMAT utilization in trimodality treatment for locally advanced esophageal cancer appears to be associated with improved OS and rates of concurrent chemoradiation therapy-related toxicity and reduced initial 12-month postoperative complications relative to SS IMRT. Multi-institutional prospective trials addressing the limitations of this study and with longer follow-ups are warranted to validate these findings.

Improper lung volume-dose parameters are risk factors for acute fatal radiation pneumonitis among esophageal cancer patients receiving chemoradiotherapy: a case-control study

Background

Definitive concurrent chemoradiotherapy (DCRT) is the standard treatment for locally advanced unresectable esophageal cancer (EC). However, acute fatal radiation pneumonitis (AFRP) is one of the most harmful complications and it is still controversial which factors pose a greater risk.

Aim

This case-control study aims to investigate the relationship between AFRP and lung volume-dose parameters in patients with esophageal cancer undergoing DCRT.

Methods

Cases are patients who died of AFRP after DCRT, whereas controls are patients who did not develop RP. Participants were enrolled using the International Classification of Diseases Codes Searching and then verified by medical record review. One-to-three propensity score matching was performed between EC patients undergoing DCRT who died from AFRP and those who did not develop radiation pneumonitis(RP). Prognostic factors were determined using univariate and multivariate analyses. The exposure factors were lung volume-dose parameters, including V5, V20, V30, and mean lung dose (MLD). Overall survival was compared between the two groups of patients before and after propensity score matching.

Results

17 cases were confirmed with AFRP among 568 EC patients were treated with DCRT between June 2008 and June 2013, and 51 cases with no RP matched by PSM method in the control group. The median V5 and MLD values in the case group were significantly higher than the control group: 88.39% versus 65.045% and 17.325 gray (Gy) versus 14.38 Gy, respectively. V5 > 60%, V20 > 25%, and MLD > 15 Gy were identified as independent risk factors for AFRP. V5 > 80% significantly increased the susceptibility to AFRP and predicted worse overall survival.

Conclusion

V5 > 60%, V20 > 25% and MLD > 15 Gy are key risk factors for AFRP in EC patients undergoing DCRT. Furthermore, V5 > 80% is a strong indicator of mortality risk.

Outcomes from a single institution cohort of 248 patients with stage I-III esophageal cancer treated with radiotherapy: Comparison of younger and older populations

Outcomes for patients receiving radiotherapy (RT) for non-metastatic esophageal cancer at a single institution were assessed, as well as the impact of factors including age and intensity modulated RT (IMRT) planning on patient outcomes. A retrospective cohort of patients treated with RT for stage I-III esophageal cancer between 2010 and 2018 was identified. Among 248 identified patients, 28 % identified as older (≥75 years of age). Other than histology, there were no other statistically significant differences in patient and tumour characteristics between the younger and older populations. Treatments varied between the two age groups, with significantly less older patients completing trimodality treatments (17 % vs 58 %). Median overall survival (M-OS) and progression-free survival (M-PFS) were 20 months and 12 months for all patients and 40 months and 26 months for trimodality patients, respectively. In the older patients, the M-OS improved from 13 months for all to 34 months for trimodality patients; and M-PFS from 10 months to 16 months. On multivariate analysis, the use of trimodality therapy showed improved OS (HR 0.26, p < 0.001). In the non-surgical older patient group, significantly better survival was seen in patients who had a heart V30Gy under 46 %. There was no significant difference in M-OS in patients planned with IMRT compared with 3D-conformal RT. Clinical outcomes in the treatment of esophageal cancer vary significantly by treatment approach, with the most favourable results in those receiving trimodality therapy. Among older patients deemed fit after assessment by the multidisciplinary team for trimodality treatments, the M-OS is comparable to the younger patient group.

Treatment Strategies for Locoregional Recurrence in Esophageal Squamous-Cell Carcinoma: An Updated Review

Emerging evidence has shown remarkable advances in the multimodal treatment of esophageal squamous-cell carcinoma. Despite these advances, the oncological outcomes for advanced esophageal cancer remain controversial due to the frequent observation of local recurrence in the regional or other lymph nodes and distant metastasis after curative treatment. For cases of locoregional recurrence in the cervical lymph nodes alone, salvage surgery with lymph node dissection generally provides a good prognosis. However, if recurrence occurs in multiple regions, the oncological efficacy of surgery may be limited. Radiotherapy/chemoradiotherapy can be employed for unresectable or recurrent cases, as well as for selected cases in neo- or adjuvant settings. Dose escalation and toxicity are potential issues with conventional three-dimensional conformal radiotherapy; however, more precise therapeutic efficacy can be obtained using technical modifications with improved targeting and conformality, or with the use of proton beam therapy. The introduction of immune checkpoint inhibitors, including pembrolizumab or nivolumab, in addition to chemotherapy, has been shown to improve the overall survival in unresectable, advanced/recurrent cases. For patients with lymph node recurrence in multiple regions, chemotherapy (5-fluorouracil [5-FU] plus cisplatin) and combination therapy with nivolumab and ipilimumab have shown comparable oncological efficacy. Further prospective studies are needed to improve the treatment outcomes in patients with esophageal cancer with locoregional recurrence.

A Meta-Analysis and Review of Radiation Dose Escalation in Definitive Radiation Therapy between Squamous Cell Carcinoma and Adenocarcinoma of Esophageal Cancer

Esophageal cancer, ranked as the eighth most prevalent cancer globally, is characterized by a low survival rate and poor prognosis. Concurrent chemoradiation therapy (CCRT) is the standard therapy in the non-surgical treatment of localized carcinoma of the esophagus. Nevertheless, the radiation doses employed in CCRT remain notably lower compared to the curative definite chemoradiation therapy utilized in the management of other carcinomas. In order to increase the local control rates and enhance the treatment outcomes, several clinical trials have used high-dose radiation to analyze the effect of dose escalation. Despite the integration of technically advanced RT schemes such as intensity-modulated radiation therapy (IMRT), the results of these trials have failed to demonstrate a significant improvement in overall survival or local progression-free survival. In this review, we investigated previous clinical trials to determine the ineffectiveness of radiation dose escalation in the context of CCRT for esophageal cancer. We aim to clarify the factors contributing to the limited efficacy of escalated radiation doses in improving patient outcomes. Furthermore, we delve into recent research endeavors, exploring prospective radiation dose modifications being altered based on the histological characteristics of the carcinoma. The exploration of these recent studies not only sheds light on potential refinements to the existing treatment protocols but also seeks to identify novel approaches that may pave the way for more efficacious and personalized therapeutic strategies for esophageal cancer management.

The effect of histologic grade on neoadjuvant treatment outcomes in esophageal cancer

BACKGROUND AND OBJECTIVES

The gold standard for locoregional esophageal cancer (LEC) treatment includes preoperative chemoradiation and surgical resection, with possible perioperative or adjuvant systemic therapy. With few data associating histologic grade and prognosis in LEC patients receiving neoadjuvant chemoradiation followed by resection, we seek to evaluate this association.

METHODS

Our institutional esophagectomy database between 1999 and 2019 was queried, selecting esophageal adenocarcinoma patients who completed neoadjuvant therapy (NAT), followed by esophagectomy. Propensity-score matching of low- and high-histologic grade groups was performed to assess survival metrics using initial clinical grade (cG) and final pathologic grade (pG). We performed a multivariable logistic regression to study predictors of pathologic complete response as a secondary objective.

RESULTS

A total of 518 patients met the inclusion criteria. Kaplan-Meier analysis of the matched dataset showed no difference in initial or 5-year recurrence-free survival or overall survival (OS) between cG1 and cG2 versus cG3 based on original grade. When matched according to pG, cG1-2 had improved median survival parameters compared to cG3, with 5-year OS for cG1-2 of 45% versus 27% (p = 0.001). Higher pG, pathologic N stage, and poor response to NAT are predictors of poor survival.

CONCLUSION

Patients with post-NAT pG1-2 demonstrated improved survival. Integrating histologic grade into postneoadjuvant staging may be warranted.

Prognostic impact of tumor length in esophageal Cancer: a systematic review and Meta-analysis

BACKGROUND

In clinical studies, it has been observed that esophageal cancer (EC) patient prognosis can be very different even for those patients with tumors of the same TNM stage. Tumor length has been analysed as a possible independent prognostic factor in many studies, but no unanimous conclusion has been reached. Therefore, this review used a meta-analysis to evaluate the association between tumor length and prognosis in EC patients.

METHODS

A systematic search for relevant articles was performed in PubMed, Web of Science, and Embase. Hazard ratios (HRs) and 95% confidence intervals (CIs) were used as effective measures to estimate the correlation between tumor length and prognosis, including overall survival, disease-free survival, progression-free survival, disease-specific survival, and cancer-specific survival. STATA 15.0 software was used to perform the meta-analysis and the data synthesis.

RESULTS

Finally, 41 articles with 28,973 patients were included in our study. The comprehensive statistical results showed that long tumors are an independent prognostic parameter associated with poor overall survival (OS) (HR = 1.30; 95% CI: 1.21-1.40, p < .001) and disease-free survival (DFS) (HR = 1.38; 95% CI: 1.18-1.61, p < .001) in EC patients. Subgroup analyses also suggested a significant correlation between long tumors and poor OS. Sensitivity analysis and publication bias evaluation confirmed the reliability and stability of the results. Similar results were obtained in the analyses of progression-free survival (PFS), disease-specific survival (DSS), and cancer-specific survival (CSS).

CONCLUSION

The results of this meta-analysis showed that long tumors were related to poor OS, DFS, PFS, DSS and CSS in EC patients. Tumor length might be an important predictor of prognosis in EC patients, and it can be used as an independent staging index. Further well-designed and large-scale prospective clinical studies are needed to confirm these findings.

Pretreatment CT and 18 F-FDG PET-based radiomic model predicting pathological complete response and loco-regional control following neoadjuvant chemoradiation in oesophageal cancer

INTRODUCTION

To develop a radiomic-based model to predict pathological complete response (pCR) and outcome following neoadjuvant chemoradiotherapy (NACRT) in oesophageal cancer.

METHODS

We analysed 68 patients with oesophageal cancer treated with NACRT followed by esophagectomy, who had staging 18F-fluorodeoxyglucose (¹⁸ F-FDG) positron emission tomography (PET) and computed tomography (CT) scans performed at our institution. An in-house data-chjmirocterization algorithm was used to extract 3D-radiomic features from the segmented primary disease. Prediction models were constructed and internally validated. Composite feature, F_c  = α * F_PET  + (1 - α) * F_CT , 0 ≤ α ≤ 1, was constructed for each corresponding CT and PET feature. Loco-regional control (LRC), recurrence-free survival (RFS), metastasis-free survival (MFS) and overall survival (OS) were estimated by Kaplan-Meier analysis, and compared using log-rank test.

RESULTS

Median follow-up was 59 months. pCR was achieved in 34 (50%) patients. Five-year RFS, LRC, MFS and OS were 67.1%, 88.5%, 75.6% and 57.6%, respectively. Tumour Regression Grade (TRG) 0-1 indicative of complete response or minimal residual disease was significantly associated with improved 5-year LRC [93.7% vs 71.8%; P = 0.020; HR 0.19, 95% CI 0.04-0.85]. Four sepjmirote pCR predictive models were built for CT alone, PET alone, CT+PET and composite. CT, PET and CT+PET models had AUC 0.73 ± 0.08, 0.66 ± 0.08 and 0.77 ± 0.07, respectively. The composite model resulted in an improvement of pCR predicting power with AUC 0.87 ± 0.06. Stratifying patients with a low versus high radiomic score showed clinically relevant improvement in 5-year LRC favouring low-score group (91.1% vs. 80%, 95% CI 0.09-1.77, P = 0.2).

CONCLUSION

The composite CT/PET radiomics model was highly predictive of pCR following NACRT. Validation in larger data sets is warranted to determine whether the model can predict clinical outcomes.

Comprehensive Comparison of Progressive Optimization Algorithm Based Automatic Plan and Manually Planned Treatment Technique for Cervical-Thoracic Esophageal Cancers

Purpose:

The purpose of the present study was first to apply the progressive optimization algorithm based automatic volumetric modulated arc therapy (POA-VMAT) technology to accelerate and improve the radiotherapy of cervicothoracic esophageal cancer (CTEC). We comprehensive analyze the feasibility, normal tissue complication probability (NTCP) and dosimetric results of POA-VMAT, manual based VMAT and step-shoot intensity-modulated radiation therapy (IMRT) plans in the treatment of CTEC.

Methods:

Sixty patients with CTEC with or without concomitant chemotherapy at our institution between 2017 and 2019 were retrospectively identified. The manual 7field-IMRT (7f-IMRT), Single-arc-VMAT and Double-arc-VMAT (Single-Arc/Double-Arc) plans were generated in all cases. The POA-VMAT was designed using the automatic dual-arc VMAT technology of Pinnacle³ 9.10 planning system based on progressive optimization algorithm. Specially, it includes the selection of treatment techniques, the running of automated planning scripts, and the evaluation of the final radiotherapy regimen. Subsequently, quantitative evaluation of plans was performed by means of standard dose–volume histograms, homogeneity index (HI) and conformity index (CI).

Results:

Target dose conformity of the 7f-IMRT plan was inferior to all plans, whereas the Double-Arc plan was slightly inferior to the POA-VMAT but superior to the Single-Arc and 7f-IMRT plan. The HI for 7f-IMRT, Single-Arc, Double-Arc and POA-VMAT were 0.17 ± 0.08, 0.28 ± 0.06, 0.29 ± 0.06 and 0.28 ± 0.03, respectively. For the NTCP results, there was significant statistical difference among POA-VMAT, IMRT and VMAT plans. The total MU was reduced by 48.3% and 42.1% in Single-Arc and POA-VMAT plans compare to IMRT plans.

Conclusions:

By comprehensive consideration, POA-VMAT efficiently generate acceptable treatment plans for CTEC without dose escalation to OARs and overall superior to manual planning which is a good option for treating CTEC.

Comparison between Intensity-Modulated Radiotherapy and Three-Dimensional Conformal Radiotherapy for Their Effectiveness in Esophageal Cancer Treatment: A Retrospective Single Institution Study

Although a large number of influential studies that have been conducted worldwide on locally advanced esophageal cancer (EC) have employed the treatment modality of three-dimensional conformal radiotherapy (3D-CRT), an advanced as well as highly conformal technology known as intensity-modulated radiotherapy (IMRT) has attracted increasing attention from the radiotherapy research community. This is because of the clear advantages of IMRT, including decrease in radiation dose that reaches critical cardiopulmonary organs. These two treatment modalities need to be investigated with regard to their effect on local control rate and patient survival. In addition, related clinical factors also need to be explored. Data from a total of 431 patients with locally advanced EC, who underwent radiation therapy between January 1, 2010 and December 31, 2013, were included in the present study. Two hundred and ninety-three patients received 3D-CRT, while 138 patients received IMRT. We constructed propensity score matches to make the two groups be comparable (136 patients in 3D-CRT group and 138 patients in IMRT group. Kaplan–Meier analysis was conducted to evaluate the endpoint of overall survival (OS). A Cox proportional hazards model was employed to analyze the relationship between the associated factors and the outcomes via univariate and multivariate approaches. The mean follow-up period was 36.2 months, and the median follow-up period was 23 months. For the IMRT group, the median OS was 31 months, and the 1-, 3-, and 5-year OS rates were 70.3%, 50.0%, and 42.8%, respectively, while for the 3D-CRT group, the median OS was 22 months, and the 1-, 3-, and 5-year OS rates were 63.2%, 41.0%, and 35.4%, respectively (p < 0.05). The univariate analysis revealed that quit drinking, chemotherapy, and concurrent chemotherapy were significant risk factors for the prognosis of EC (p < 0.05), as well as the radiation therapy technique used (p=0.052). The multivariate analysis indicated that chemotherapy and quit drinking were independent predictive factors for OS. OS is found to be significantly better in the IMRT group, compared with that of the 3D-CRT group. Even though these outcomes need further validation, IMRT should be considered preferentially as a therapeutic option for EC, in combination with chemotherapy and persuading patients to quit drinking.

Expression of miR-1304 in patients with esophageal carcinoma and risk factors for recurrence

BACKGROUND

Esophageal carcinoma is a malignant gastrointestinal tumor with a very poor prognosis. MicroRNA (miR)-1304 is a newly discovered non-coding RNA, which shows differential expression in other cancers, and its clinical value in esophageal carcinoma remains unclear.

AIM

To explore the expression of miR-1304 in patients with esophageal carcinoma and its clinical value.

METHODS

The expression of miR-1304 in patients with esophageal carcinoma was analyzed based on the data on miR in esophageal carcinoma downloaded from The Cancer Genome Atlas database. Quantitative real-time polymerase chain reaction was adopted to determine the expression of miR-1304 in the tissues and serum of patients. The clinical diagnostic value of miR-1304 and independent factors for recurrence and prognosis of esophageal carcinoma were then analyzed. The potential target genes of miR-1304 were predicted, and then analyzed based on gene ontology, Kyoto Encyclopedia of Genes, and Genomes, and protein-protein interaction.

RESULTS

The expression of miR-1304 in the tissues and serum of patients with esophageal carcinoma increased, and was also increased according to the database. Patients with high expression of miR-1304 suffered increased rates of tumor ≥ 3 cm, low differentiation and stage II + III. miR-1304 had a diagnostic value in identifying esophageal carcinoma, tumor size, differentiation and TNM stage. Tumor size, differentiation, TNM stage, and miR-1304 were independent risk factors for recurrence of esophageal carcinoma, and they had certain predictive and diagnostic value for the recurrence of esophageal carcinoma. Seventy-eight patients showed a 3-year survival rate of 38.46%, and patients with high expression of miR-1304 had a relatively lower survival rate. Multivariate analysis revealed that tumor size, differentiation, recurrence and miR-1304 were independent factors for the prognosis of patients. MiRTarBase, miRDB, and Targetscan predicted 20 target genes in total. Gene ontology enrichment analysis found 18 functions with ^aP < 0.05, and Kyoto Encyclopedia of Genes, and Genomes analysis found 11 signal pathways with ^aP < 0.05. String analysis of protein co-expression found 269 relationship pairs, of which co-expression with epidermal growth factor was the most common.

CONCLUSION

miR-1304 can be used as a potential indicator for the diagnosis and recurrence of esophageal carcinoma and for survival of patients with this disease.

Effect of lung volume on helical radiotherapy in esophageal cancer: are there predictive factors to achieve acceptable lung doses?

PURPOSE

The dose received by the lungs in radiotherapy (RT) is affected by the patient's current lung volume. The presence of predictive factors and cut-off points were investigated to achieve acceptable lung doses in esophageal cancer (EC) treatment.

METHODS

Virtual RT volumes of supracarinal EC were delineated. RT plans were designed with standard criteria in the TomoTherapy planning system (TomoTherapy Inc., Madison, WI, USA). The total dose was 50.4 Gy (1.8 Gy/fraction). ROC (Receiver operating characteristic) analysis and Mann-Whitney U tests were performed.

RESULTS

There was a total of 65 patient plans included. ROC analysis showed that lung/PTV (Planning target volume) volume ratio (AUC [Area under curve]: 0.91, 95% CI: 0.83-0.99, p = 0.000) and bilateral lung volume (AUC: 0.81, 95% CI: 0.70-0.92, p = 0.000) have diagnostic power to predict the suitability of RT plans according to QUANTEC (Quantitative Analyses of Normal Tissue Effects in the Clinic) for lung dose constraints. The cut-off points of 7 and 3500 cc were selected for lung/PTV ratio and bilateral lung volume, respectively. The effect of the cut-off points on the dose data was assessed with the Mann-Whitney U test. The mean lung and heart doses, lung V5, V15, and V20, as well as heart V5, V20, V30, and V45 values were found to be lower in both groups separated by cut-off points (p < 0.05).

CONCLUSION

The lung/PTV ratio ≥7 and bilateral lung volume ≥3500 cc cut-off points are predictive of whether TomoTherapy plans may meet QUANTEC lung dose limits in patients with supracarinal esophageal cancer. The patients with lung/PTV ratio and lung volume above these cut-off points may be candidates for treatment with TomoTherapy.

Intensity-modulated radiotherapy does not decrease the risk of malnutrition in esophageal cancer patients during radiotherapy compared to three-dimensional conformal radiation therapy

Background

Esophageal cancer is a lethal disease of global scope. Radiotherapy is the main method to treat esophageal cancer; however, it concurrently leads to malnutrition. Intensity-modulated radiotherapy (IMRT) is superior to three-dimensional conformal radiation therapy (3D-CRT) in dosimetry and clinical outcomes. In this cohort study, we aimed to compare the effect of 3D-CRT and IMRT on malnutrition status.

Methods

We retrospectively included 79 esophageal cancer patients (IMRT: n=27, 3D-CRT: n=52) who received radiotherapy. We collected nutrition indexes at the beginning, the second week, and the end of radiotherapy. Paired-T test was used to evaluate the nutrition status during radiotherapy in each group. Chi-square test and independent-sample T-test were applied to compare the dynamic changes of indexes between IMRT and 3D-CRT groups.

Results

The baselines of the two groups are comparable. Nutrition Risk Screening 2002 (NRS-2002) score, body weight, BMI, hemoglobin, lymphocyte, total protein, and albumin values were significantly reduced during radiotherapy in both groups. The dynamic changes of nutrition indexes during radiotherapy were not significantly different between the IMRT and 3D-CRT groups. Besides, no difference was found for radiation esophagitis or treatment completion between the two groups.

Conclusions

Malnutrition occurs in esophageal cancer patients during radiotherapy. IMRT did not significantly decrease the risk of malnutrition compared to 3D-CRT.

Quality Assurance of Dose-Escalated Radiation Therapy in a Randomized Trial for Locally Advanced Oesophageal cancer

PURPOSE

The ongoing phase 2/3 PRODIGE 26/CONCORDE trial compares chemoradiation therapy with and without dose escalation in patients with locally advanced or unresectable esophageal cancer. The results of a benchmark case procedure are reported here to evaluate the protocol compliance of participating centers as part of quality assurance for radiation therapy.

METHODS AND MATERIALS

Volume delineation, target coverage, and dose constraints to the organs at risk (OARs) were assessed on treatment plans of a common benchmark case performed by each participating center. The centers were classified in 3 categories: per protocol, minor acceptable deviation (MiD), or major unacceptable deviation (MaD). A plan was rejected if ≥4 MiDs or 1 MaD were found.

RESULTS

Thirty-5 centers submitted 43 plans. Among them, 14 (32.6%) were per protocol, 19 (44.2%) presented at least 1 MiD, 2 (4.6%) presented at least 1 MaD, and 8 (18.6%) presented both MiD and MaD. Overall, 11 (25.6%) plans were rejected. Only 1 plan was rejected because gross tumor volume was not correctly delineated. The OAR delineation was respected in all cases. Dose constraints to the OARs were respected in the majority of cases except for the heart, where one-third of the plans presented a deviation. As for the target volume, 3 plans (5.8%) had a major underdosage and 1 plan (1.9%) had a major overdosage. Overall, 58% of all treatments were planned with intensity modulated radiation therapy, whereas 42% were planned with 3-dimensional chemoradiation therapy. Significantly more plans in the intensity modulated radiation therapy group were accepted compared with the 3-dimensional chemoradiation therapy group (P = .03).

CONCLUSION

The high frequency of protocol deviations underlines the importance of a quality assurance program in clinical trials. Further work should assess the impact of quality assurance for radiation therapy on patient outcomes.

Outcomes and prognostic factors for patients with cervical esophageal cancer undergoing definitive radiotherapy or chemoradiotherapy

Cervical esophageal cancer (CEC) is uncommon, accounting for less than 5% of all esophageal cancers. The management of CEC is controversial. This study investigated treatment outcomes and prognostic factors of survival in CEC patients undergoing definitive radiotherapy or concurrent chemoradiotherapy (CCRT). Ninety-one CEC patients were treated by intensity-modulated radiation therapy (IMRT) and three-dimensional conformal radiation therapy (3DCRT) between July 2007 and September 2017. The mean prescription dose was 64 Gy (range 54-70 Gy) delivered as 1.8-2.2 Gy per fraction per day, 5 days a week. Out of 91 patients, 34 received concurrent cisplatin-based chemotherapy (CT) including 18 patients who also received neoadjuvant CT. Overall survival (OS), locoregional failure-free survival (LRFFS), and progression-free survival (PFS) were estimated by the Kaplan-Meier method. Prognostic factors of survival were determined in univariate (log-rank test) and multivariate (Cox proportional hazard model) analysis. Treatment-related toxicity was also assessed. Median follow-up time for all patients was 19 months. Two-year OS, LRFFS and PFS of all patients were 58.2%, 52.5% and 48.1%, respectively. Clinical stage was an independent prognostic factor for OS (HR = 2.35, 95% CI: 1.03-5.37, p = 0.042), LRFFS (HR = 3.84, 95% CI: 1.38-10.69, p = 0.011), and PFS (HR = 2.68, 95% CI: 1.11-6.45, p = 0.028). Hoarseness was an independent prognostic factor for OS (HR = 2.10, 95% CI: 1.05-4.19, p = 0.036). CCRT was independently associated with better LRFFS (HR = 0.33, 95% CI: 0.14-0.79, p = 0.012). 3DCRT and IMRT with concurrent CT is well-tolerated and may improve local tumor control in CEC patients. Advanced clinical stage and hoarseness are adverse prognostic factors for OS, LRFFS, and PFS in CEC.

Intensity-Modulated Radiotherapy versus Three-Dimensional Conformal Radiotherapy in Definitive Chemoradiotherapy for Cervical Esophageal Squamous Cell Carcinoma: Comparison of Survival Outcomes and Toxicities

PURPOSE

The purpose of this study was to compare the survival and toxicities in cervical esophageal squamous cell carcinoma (CESCC) treated by concurrent chemoradiothrapy with either three-dimensional conformal radiotherapy (3D-CRT) or intensity-modulated radiotherapy (IMRT) techniques.

Materials and Methods

A total of 112 consecutive CESCC patients were retrospectively reviewed. 3D-CRT and IMRT groups had been analyzed by propensity score matching method, with sex, age, Karnofsky performance status, induction chemotherapy, and tumor stage well matched. The Kaplan-Meier method and Cox proportional hazards model were used for overall survival (OS) and progression-free survival (PFS). Toxicities were compared between two groups by Fisher exact test.

RESULTS

With a median follow-up time of 34.9 months, the 3-year OS (p=0.927) and PFS (p=0.859) rate was 49.6% and 45.8% in 3D-CRT group, compared with 54.4% and 42.8% in IMRT group. The rates of grade ≥ 3 esophagitis, grade ≥ 2 pneumonitis, esophageal stricture, and hemorrhage were comparable between two groups, while the rate of tracheostomy dependence was much higher in IMRT group than 3D-CRT group (14.3% vs.1.8%, p=0.032). Radiotherapy technique (hazard ratio [HR], 0.09; 95% confidence interval [CI], 0.01 to 0.79) and pretreatment hoarseness (HR, 0.12; 95% CI 0.02 to 0.70) were independently prognostic of tracheostomy dependence.

CONCLUSION

No survival benefits had been observed while comparing IMRT versus 3D-CRT in CESCC patients. IMRT with fraction dose escalation and pretreatment hoarseness were considered to be associated with a higher risk for tracheostomy dependence. Radiation dose escalation beyond 60 Gy should be taken into account carefully when using IMRT with hypofractionated regimen.

Proposed revision of the 8th edition AJCC clinical staging system for esophageal squamous cell cancer treated with definitive chemo-IMRT based on CT imaging

Purpose

To validate and propose revision of the 8th edition American Joint Committee on Cancer (AJCC) clinical staging system for esophageal squamous cell cancer (ESCC) patients treated with definitive intensity-modulated radiation therapy combined with concurrent chemotherapy (Chemo-IMRT) based on computed tomography (CT) imaging.

Methods

The clinical data of patients with ESCC treated with Chemo-IMRT were collected and retrospectively reviewed. All CT images were independently reevaluated and restaged according to the 8th edition AJCC staging system. The overall survival (OS) rates were analyzed statistically. ROC curves of the various parameters of the primary tumor and metastatic lymph nodes were generated in order to identify the cutoff values correlated to patient survival using the area under curve.

Results

The gross tumor volume of the primary tumor (GTV-prT) and the clinical N stage (cN) were independent factors that influenced OS. The 5-year OS rate of patients with GTV-prT ≤28 cm³, GTV-prT > 28 and ≤ 56 cm³, and GTV-prT > 56 cm³ were 54.6, 31.1 and 18.6%, respectively. The 5-year OS rate of patients with cN0, cN1 SLNM (−), cN2 SLNM (−), cN3 SLNM (−) and SLNM (+) were 62.8 (P < 0.001), 34.0 (P = 0.16), 20.0 (P = 0.785), 0 (P < 0.001) and 26.9%, respectively. After restaging the SLNM as regional MLNs, the 5-year OS rates of the patients with cN0, 1, 2 and 3 were 62.8, 36.3, 23.7 and 7.8%, respectively. Various GTV-prT were combined with the cN to establish a new clinical TNM staging system: I, GTV-prT1 and cN0; II, GTV-prT2 or 3 and cN0, GTV-prT1 and cN1; III, GTV-prT1 and cN2, GTV-prT2 and cN1,2; Iva, GTV-prT3 and cN1,2; IVb, GTV-prT_any and cN3; IVc, T_anyN_anyM1. Subsequently, the OS differed significantly between the adjacent GTV-prT cN categories, except those of stage I vs. II.

Conclusion

The SLNM should be dealt with as a regional rather than a distant disease in patients with ESCC when treated with CRT. The proposed nonsurgical staging system based on the GTV-prT and N appears to be a simple and accurate prognosis predictor for patients with ESCC who have undergone definitive Chemo-IMRT.

A new clinical staging system for esophageal cancer to predict survival after definitive chemoradiation or radiotherapy

This study is to evaluate the prognostic value of a new clinical staging system for esophageal cancer to predict survival after (chemo)radiotherapy. This retrospective study enrolled 444 patients with esophageal squamous cell carcinoma who underwent definitive intensity-modulated radiotherapy with or without chemotherapy between January 2008 and May 2014. A clinical staging system based on the gross tumor volume and maximum diameter of metastatic lymph nodes was developed and the prognostic value of this staging system was compared with that of the 8th edition of American Joint Committee on Cancer TNM staging system. The 3-year survival rate in the whole group was 44.5%. Multivariate analysis showed that gross tumor volume and maximum diameter of metastatic lymph nodes were independent prognostic factors. According to the proposed clinical staging system, the 3-year survival curves of each T, N, and TNM stage were well segregated. On the other hand, 3-year survival rates based on the 8th edition of cTNM staging system were similar between cT3 and cT4, cN1 and cN2, cN2, and cN3, III and IVa stages.The proposed clinical staging system appears to be a simple and accurate predictor of outcome in patients with esophageal squamous cell carcinoma who underwent definitive (chemo) intensity-modulated radiotherapy.

Proton beam therapy for gastrointestinal cancers: past, present, and future

Despite the conformality of modern X-ray therapy limiting high dose received by normal tissues the physical properties of X-rays make it impossible to avoid dose being delivered distal to the target. This "exit dose" is likely clinically significant especially for patients with gastrointestinal (GI) cancers when considering that even low dose received by the heart, lungs, bowel, and other radiosensitive structures can lead to morbidity and even may affect long-term tumor control. In contrast, proton beam therapy (PBT) delivers no "exit dose" and a growing body of literature suggests that this may improve clinical outcomes by reducing toxicity and even allowing for safe dose intensification to enhance tumor control. While there are not yet robust prospective data demonstrating the role of PBT for GI cancers, emerging retrospective data provide a strong rationale for continued study of how PBT may improve the therapeutic ratio for these patients. Here we review these data as well as discuss ongoing clinical trials of PBT for GI cancers.

Clinical outcome of elderly patients (≥ 70 years) with esophageal cancer undergoing definitive or neoadjuvant radio(chemo)therapy: a retrospective single center analysis

BACKGROUND

To analyse the outcome of elderly patients (≥70 years) with esophageal cancer treated with curative intent radio(chemo)therapy.

METHODS

Fifty five patients (median 75 years) receiving curative intent radio(chemo)therapy for esophageal cancer from 1999 to 2015 were retrospectively analyzed. Most patients showed locally advanced disease (T3/4:78%, N+:58%) with squamous cell histology (74%). Charlson comorbidity score was > 1 in 27%. 48 patients (87%) received definitive treatment while 7 patients were treated neoadjuvantly. RT was carried out as 3D-conformal treatment or IMRT. Concurrent chemotherapy was applied in 85%, mainly cisplatin/5-FU or mitomycin/5-FU. ¹⁸FDG-PET/CT staging was used in 65%.

RESULTS

Median follow-up was 11 months (1-68) and 21 months in survivors. 1- and 2-year rates of LRC, DC, FFTF and OS were 60%/45, 81%/72, 55%/41 and 46%/26% for the entire cohort. In univariate analysis, addition of surgery was associated with improved LRC and FFTF, nodal involvement with improved DC and lower T stage, lower Charlson score and use of PET-CT with improved OS. In multivariate analysis, lower T stage and lower Charlson score remained significant for OS. Patients treated after 2008 showed a significantly improved FFTF (1-year FFTF 64% vs 35%) and OS (1-year OS 66% vs 24%). Maximum (chemo)radiation related grade3+ toxicity was observed in 80% including 7 deaths (13%). Grade5 toxicity was significantly associated with Charlson score (CS > 1:33% vs CS ≤ 1:5%) and treatment period (24% before vs 3% after 2008). The patients treated after 2008 included significantly more SCCs, less T4 stages, had a higher percentage of PET-CT staging and were treated with smaller field lengths. Trends were also observed for lower Charlson scores and increased use of IMRT.

CONCLUSION

Curative intent (chemo)radiation of elderly patients with esophageal cancer may result in considerable toxicity and unfavorable outcome. However, a clear improvement over time was observed in our cohort, probably based on improved patient selection. In patients with less advanced stages and lower comorbidity similar results as in younger cohorts seem achievable with modern staging and treatment approaches. Age per se should not be a decisive factor, but careful attention should be paid regarding patient selection including a structured and tight follow-up strategy.

Increased evidence for the prognostic value of FDG uptake on late-treatment PET in non-tumour-affected oesophagus in irradiated patients with oesophageal carcinoma

PURPOSE

¹⁸F-FDG uptake in irradiated non-tumour-affected oesophagus (NTO) on restaging PET is a potential surrogate for the measurement of radiation-induced inflammation. Radiation-induced inflammation itself has been shown to be of high prognostic relevance in patients undergoing preoperative radiochemotherapy (RCT) for locally advanced oesophageal cancer. We assessed the prognostic relevance of FDG uptake in the NTO in an independent cohort of patients treated with definitive RCT.

METHODS

This retrospective evaluation included 72 patients with oesophageal squamous cell carcinoma treated with definitive RCT with curative intent. All patients underwent pretreatment and restaging FDG PET after receiving a radiation dose of 40-50 Gy. Standardized uptake values (SUV_max/SUV_mean), metabolic tumour volume (MTV) and relative changes from pretreatment to restaging PET (∆SUV_max/∆SUV_mean) were determined within the tumour and NTO. Univariate Cox regression with respect to overall survival (OS), local control (LC), distant metastases (DM) and treatment failure (TF) was performed. Independence of parameters was tested by multivariate Cox regression.

RESULTS

∆SUV_max NTO and MTV were prognostic factors for all investigated clinical endpoints (OS, LC, DM, TF). Inclusion of clinical and PET tumour parameters in multivariate analysis showed that ∆SUV_max NTO was an independent prognostic factor. Furthermore, multivariate analysis of ∆SUV_max NTO using previously published cut-off values from preoperatively treated patients revealed that ∆SUV_max NTO was independent prognostic factor for OS (HR = 1.88, p = 0.038), TF (HR = 2.11, p = 0.048) and DM (HR = 3.02, p = 0.047).

CONCLUSION

NTO-related tracer uptake during the course of treatment in patients with oesophageal carcinoma was shown to be of high prognostic relevance. Thus, metabolically activity of NTO measured in terms of ∆SUV_max NTO is a potential candidate for future treatment individualization (i.e. organ preservation).

Utilization of neoadjuvant intensity-modulated radiation therapy and proton beam therapy for esophageal cancer in the United States

Background

Randomized esophageal cancer (EC) trials have utilized two- or three-dimensional conformal radiotherapy (3DCRT). Advanced radiotherapy (RT) techniques [(ARTs): intensity-modulated radiotherapy (IMRT) and proton beam therapy (PBT)] may have benefits, but are relatively unproven. This is the first study to date evaluating utilization of ARTs versus 3DCRT in the trimodality setting in the United States.

Methods

The National Cancer Data Base (NCDB) was queried (2004-2013) for newly-diagnosed cT1b-T4bN0/N+M0 EC receiving neoadjuvant CRT followed by esophagectomy. The primary objective was to assess temporal trends, with multivariable logistic regression analysis assessing factors predictive of receiving ARTs. Secondarily, Kaplan-Meier analysis evaluated overall survival (OS), Cox proportional hazards modeling determined variables associated with OS, and postoperative complications were compared between cohorts.

Results

Altogether, 3,138 patients met criteria; 1,398 (45%) received 3DCRT, and 1,740 (55%) received ARTs (99% IMRT, 1% PBT). Temporally, utilization of ARTs is steadily rising in the United States, from 20% in 2004 to 69% in 2013, corresponding with a progressive decrease in utilization of 3DCRT. ARTs were more often delivered with advancing age, squamous cell histology, N2+ disease, and at academic centers (P<0.05 for all). Centers in the Southwest were more likely to use ARTs, and those in the Midwest least likely (P<0.05 for both). As expected, there were no OS differences (P=0.8477); there were also no differences in postoperative events (P>0.05 for all). Treatment at an academic center independently correlated with improved OS (P<0.001).

Conclusions

Utilization of ARTs (IMRT in the vast majority) is steadily rising in the United States; 3DCRT is now used in a minority of patients. This has implications for payers and insurance coverage. ART use is impacted by not only age and disease factors, but also regional and facility differences. Treatment at an academic facility independently correlated with higher survival, which has implications for patient counseling.

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.

Novel use of proton beam therapy for neoadjuvant treatment of radiation-associated squamous cell carcinoma of the esophagus

Secondary esophageal cancers from prior thoracic radiation therapy are rare but challenging cases to deliver standard combined modality therapy as part of a curative approach. In patients with prior exposure to cardiopulmonary-toxic chemotherapy or radiotherapy, management requires meticulous multidisciplinary evaluation given the morbidity associated with surgery in the previously irradiated thorax and re-irradiation of the spinal cord, heart, and lungs. Oftentimes, suboptimal treatment regimens, either with compromised radiation coverage, attenuated chemotherapy doses, or exclusion of surgery, are required to avoid significant toxicity. The physical properties inherent to protons allow for optimal coverage of tumor while achieving remarkably low dose to surrounding normal tissue compared to standard photon treatment. Proton therapy has been studied across various disease sites and may facilitate treatment intensification for radiation-associated esophageal tumors. While no comparative studies have evaluated the efficacy and safety of protons versus photons for esophageal cancer, three cases of radiation-associated esophageal cancer presented in this series are exemplary to highlight the benefit of protons in this unique clinical circumstance. The technical considerations in planning, including passively scattered versus pencil-beam scanning technique, as well as the clinical course and tolerance to treatment, are discussed, which may guide consideration of this advanced treatment modality in this disease site.

Radiation dose escalation by simultaneous modulated accelerated radiotherapy combined with chemotherapy for esophageal cancer: a phase II study

The outcomes for patients with esophageal cancer (EC) underwent standard-dose radical radiotherapy were still disappointing. This phase II study investigated the feasibility, safety and efficacy of radiation dose escalation using simultaneous modulated accelerated radiotherapy (SMART) combined with chemotherapy in 60 EC patients. Radiotherapy consisted of 66Gy at 2.2 Gy/fraction to the gross tumor and 54Gy at 1.8 Gy/fraction to subclinical diseases simultaneously. Chemotherapy including cisplatin and 5fluorouracil were administered to all patients during and after radiotherapy. The data showed that the majority of patients (98.3%) completed the whole course of radiotherapy and concurrent chemotherapy. The most common ≥ grade 3 acute toxicities were neutropenia (16.7%), followed by esophagitis (6.7%) and thrombopenia (5.0%). With a median follow-up of 24 months (5-38) for all patients and 30 months (18-38) for those still alive, 11 patients (18.3%) developed ≥ Grade 3 late toxicities and 2 (3.3%) of them died subsequently due to esophageal hemorrhage. The 1- and 2-year local-regional control, distant metastasis-free survival, disease-free survival and overall survival rates were 87.6% and 78.6%, 86.0% and 80.5%, 75.6% and 64.4%, 86.7% and 72.7%, respectively. SMART combined with concurrent chemotherapy is feasible in EC patients with tolerable acute toxicities. They showed a trend of significant improvements in local-regional control and overall survival. Further follow-up is needed to evaluate the late toxicities.

Volumetric-modulated arc therapy versus intensity-modulated radiotherapy for large volume retroperitoneal sarcomas: A comparative analysis of dosimetric and treatment delivery parameters

Purpose

To compare dosimetric and treatment delivery parameter differences between volumetric‐modulated arc radiotherapy (VMAT) and intensity‐modulated radiotherapy (IMRT) for large volume retroperitoneal sarcomas (RPS).

Materials and Methods

Both VMAT and IMRT planning were performed on CT datasets of 10 patients with RPS who had been previously treated with preoperative radiotherapy. Plans were optimized to deliver ≥95% dose to the PTV and were evaluated for conformity and homogeneity. Dose to the organs at risk (OARs) (kidney, liver, spinal cord, and bowel space), unspecified tissue, and dose evaluation volumes (DEVs) at 1, 2, and 5 cm from PTV were calculated and compared. Monitor units (MUs) and treatment delivery times were recorded and compared between the two techniques. The deliverability of the large volume RPS VMAT plans was verified by portal dosimetry on a Truebeam™ linac.

Results

VMAT and IMRT plans were equivalent for PTV coverage and homogeneity (P > 0.05); however, VMAT plans had slightly better conformity index, CI (P < 0.001). Doses to the OARs were not significantly different between VMAT and IMRT plans (P > 0.05). Mean doses to the unspecified tissue as well as at 1, 2, and 5 cm DEVs were lower with VMAT compared with IMRT, P = 0.04 and P < 0.01, respectively. MUs and average beam‐on times were both significantly lower in the VMAT vs IMRT plans, P < 0.001 and P = 0.001, respectively. All VMAT plans passed portal dosimetry delivery verification with an average gamma passing rate of 99.6 ± 0.4%.

Conclusions

VMAT planning for large volume RPS improved CI, and achieved comparable OAR sparing, as compared with IMRT. As treatment delivery time was lower, the use of VMAT for RPS may translate into improved treatment delivery efficiency.

Intensity-modulated versus 3-dimensional conformal radiotherapy in the definitive treatment of esophageal cancer: comparison of outcomes and acute toxicity

Background

Though the vast majority of seminal trials for locally advanced esophageal cancer (EC) utilized three-dimensional conformal radiotherapy (3DCRT), the advanced and highly conformal technology known as intensity-modulated radiotherapy (IMRT) can decrease doses to critical cardiopulmonary organs. To date, there have been no studies comparing both modalities as part of definitive chemoradiation (dCRT) for EC. Herein, we investigated local control and survival and evaluated clinical factors associated with these endpoints between cohorts.

Methods

We retrospectively analyzed 93 patients (3DCRT n = 49, IMRT n = 44) who received dCRT at our institution between 2000 and 2012 with the histologic diagnosis of nonmetastatic EC, a Karnofsky performance status of ≥70, curative treatment intent, and receipt of concomitant CRT. Patients were excluded if receiving <50 Gy. Kaplan-Meier analysis was used to evaluate the endpoints of local relapse rate (LR), progression-free survival (PFS), and overall survival (OS). Cox proportional hazards modeling addressed factors associated with outcomes with univariate and multivariate approaches. Rates of acute toxicities and basic dosimetric parameters were compared between 3DCRT and IMRT patients.

Results

Mean follow-up was 34.7 months. The 3-year LR was 28.6% in the 3DCRT group and 22.7% in the IMRT group (p = 0.620). Median PFS were 13.8 and 16.6 months, respectively (p = 0.448). Median OS were 18.4 and 42.0 months, respectively (p = 0.198). On univariate analysis, only cumulative radiation dose was associated with superior LR (hazard ratio (HR) 0.736; 95% confidence interval (CI) 0.635 – 0.916, p = 0.004). Factors clearly affecting survival were not observed.

Conclusions

When comparing 3DCRT- versus IMRT-based dCRT, no survival benefits were observed. However, we found a lower local recurrence rate in the IMRT group potentially owing to dose-escalation. Prospective data are needed to verify the presented results herein.

Intensity-modulated radiotherapy combined with paclitaxel and platinum treatment regimens in locally advanced esophageal squamous cell carcinoma

PURPOSE

This study was conducted to investigate the efficacy and toxicity of combination treatment with intensity-modulated radiotherapy (IMRT) and concurrent chemotherapy with paclitaxel plus different platinum agents in locally advanced esophageal squamous cell carcinoma (ESCC).

METHODS

This retrospective study enrolled 242 patients treated with paclitaxel (135 mg/m²) plus platinum regimens. According to the different platinum agents used, patients were classified into: cisplatin 80 mg/m² (CP), nidaplatinum 80 mg/m² (NP), lobaplatin 35 mg/m² (LP), and oxaliplatin 135 mg m² (OP) groups, and survival and toxicity rates between the four groups were compared. The median overall survival (OS) was 31.1 months.

RESULTS

No significant differences were observed among the CP, NP, LP, and OP groups with regard to 3-year survival rates (46.2, 56.4, 45.7, and 29.0%, respectively). A stratified analysis indicated that 3-year survival rates were significantly lower in the OP group. Renal toxicities and gastrointestinal reactions were more frequent in the CP group than in the other three groups. Three-year survival rates were similar among patients receiving 2, 3, or ≥4 cycles of chemotherapy (40.1, 49.5, and 50.8%, respectively). Multivariate analysis indicated that tumor volume and maximum diameter of metastatic lymph nodes might be independent prognostic factors.

CONCLUSION

Paclitaxel plus nidaplatinum or lobaplatin is recommended in locally advanced ESCC due to their satisfying therapeutic effects and less toxicity. Tumor volume and maximum diameter of metastatic lymph nodes are independent prognostic factors in ESCC patients receiving IMRT and concurrent chemotherapy.

Fiducial markers coupled with 3D PET/CT offer more accurate radiation treatment delivery for locally advanced esophageal cancer

BACKGROUND AND AIMS

 The role of three-dimensional positron emission tomography/computed tomography (3 D PET/CT) in esophageal tumors that move with respiration and have potential for significant mucosal inflammation is unclear. The aim of this study was to determine the correlation between gross tumor volumes derived from 3 D PET/CT and endoscopically placed fiducial markers.

METHODS

 This was a retrospective, IRB approved analysis of 40 patients with esophageal cancer with fiducials implanted and PET/CT. The centroid of each fiducial was identified on PET/CT images. Distance between tumor volume and fiducials was measured using axial slices. Image features were extracted and tested for pathologic response predictability.

RESULTS

 The median adaptively calculated threshold value of the standardized uptake value (SUV) to define the metabolic tumor volume (MTV) border was 2.50, which corresponded to a median 23 % of the maximum SUV. The median distance between the inferior fiducial centroid and MTV was - 0.60 cm (- 3.9 to 2.7 cm). The median distance between the superior fiducial centroid and MTV was 1.25 cm (- 4.2 to 6.9 cm). There was no correlation between MTV-to-fiducial distances greater than 2 cm and the gastroenterologist who performed the fiducial implantation. Eccentricity demonstrated statistically significant correlations with pathologic response.

CONCLUSIONS

 There was a stronger correlation between inferior fiducial location and MTV border compared to the superior extent. The etiology of the discordance superiorly is unclear, potentially representing benign secondary esophagitis, presence of malignant nodes, inflammation caused by technical aspects of the fiducial placement itself, or potential submucosal disease. Given the concordance inferiorly and the ability to more precisely set up the patient with daily image guidance matching to fiducials, it may be possible to minimize the planning tumor volume (PTV) margin in select patients, thereby, limiting dose to normal structures.

Recent advances in intensity modulated radiotherapy and proton therapy for esophageal cancer

INTRODUCTION

Radiotherapy is an important component of the standard of care for esophageal cancer. In the past decades, significant improvements in the planning and delivery of radiation techniques have led to better dose conformity to the target volume and improved normal tissue sparing. Areas covered: This review focuses on the advances in radiotherapy techniques and summarizes the availably dosimetric and clinical outcomes of intensity-modulated radiation therapy (IMRT), volumetric modulated arc therapy, proton therapy, and four-dimensional radiotherapy for esophageal cancer, and discusses the challenges and future development of proton therapy. Expert commentary: Although three-dimensional conformal radiotherapy is the standard radiotherapy technique in esophageal cancer, the retrospectively comparative studies strongly suggest that the dosimetric advantage of IMRT over three-dimensional conformal radiotherapy can translate into improved clinical outcomes, despite the lack of prospective randomized evidence. As a novel form of conventional IMRT technique, volumetric modulated arc therapy can produce equivalent or superior dosimetric quality with significantly higher treatment efficiency in esophageal cancer. Compared with photon therapy, proton therapy has the potential to achieve further clinical improvement due to their physical properties; however, prospective clinical data, long-term results, and cost-effectiveness are needed.

Long-term survival and toxicity outcomes of intensity modulated radiation therapy for the treatment of esophageal cancer: A large single-institutional cohort study

Purpose

In patients with esophageal cancer (EC), intensity modulated radiation therapy (IMRT) improves dose sparing to the heart and lung, with some evidence showing clinical benefit. Herein, we report our cumulative clinical experience with the use of IMRT for EC.

Methods and materials

This is a retrospective analysis of 587 patients with nonmetastatic EC who were treated consecutively with IMRT from January 2004 to June 30, 2013. All patients with stage I-IVA (American Joint Committee on Cancer 2002) received concurrent chemoradiation therapy either preoperatively or definitively. The Kaplan-Meier method was used to compute overall survival (OS) and locoregional recurrence-free survival and disease-free survival. The Common Terminology Criteria for Adverse Events, Version 4.0 were used to grade acute and subacute complications.

Results

The median radiation dose was 50.4 Gy in 28 daily fractions. As of July 2015, the median follow-up was 31.4 months (range, 2.9-130.7 months) for all patients and 61.8 months (range, 7.7-130.7 months) for survivors. The median OS was 38.9 months, and the 1-, 3-, and 5-year OS rates were 86.7%, 51.8%, and 41.2%, respectively. The 1-, 3-, and 5-year locoregional recurrence-free survival rates were 77.6%, 68.2%, and 66.1%, respectively, and the 1-, 3-, and 5-year disease-free survival rates were 58.6%, 43.7%, and 41.4%, respectively. Outcomes for both trimodality and bimodality treated patients were better than the outcomes reported in the literature. Eight patients (1.4%) experienced grade ≥3 pneumonitis, and 74 patients (13%) developed grade ≥3 esophagitis. For patients who underwent surgery, the most common postoperative complications were pneumonia (9.6%), anastomotic leakage (11.1%), and atrial fibrillation (12.5%).

Conclusions

This is the largest, single institutional study to date on the long-term outcomes of treatment with IMRT for EC. For photon-based radiation therapy, IMRT yields excellent outcomes and should be considered for the treatment of EC.

The Impact of Postoperative Conformal Radiotherapy after Radical Surgery on Survival and Recurrence in Pathologic T3N0M0 Esophageal Carcinoma: A Propensity Score-Matched Analysis

INTRODUCTION

The role of conformal radiotherapy (cRT) in thoracic esophageal squamous cell carcinoma (TESCC) has not been addressed in adjuvant settings. The aim of this study was to investigate whether postoperative radiotherapy using cRT after an R0 resection improves outcomes in pT3N0M0 TESCC compared with resection alone.

METHODS

This study included 678 patients with pT3N0M0 TESCC who were treated at the Cancer Hospital, Chinese Academy of Medical Sciences, from January 2004 to December 2011. The patients were divided into two groups: a surgery plus cRT group (S+cRT group) comprising patients who underwent cRT after an R0 resection and a surgery group (S group), comprising a control group of patients who underwent an R0 resection alone. Propensity score matching was used to create patient groups that were balanced across several covariates (n = 83 in each group). Outcome measures included overall survival (OS), disease-free survival (DFS), and recurrence.

RESULTS

In the overall study cohort, 5-year OS (75.2% versus 58.5%, p = 0.004) and DFS (71.8% versus 49.2%, p = 0.001) rates were significantly higher in the S+cRT group than in the S group. These data were confirmed in the matched samples (5-year OS, 75.7% versus 58.8% [p = 0.017]; DFS, 71.7% versus 50.3% [p = 0.009]). The overall (p = 0.001) and locoregional (p = 0.004) recurrence rates in the S+cRT group were significantly lower than in the S group. Multivariate Cox analyses in the matched samples revealed that surgery and postoperative cRT were independently associated with longer OS (hazard ratio = 0.505, 95% confidence interval: 0.291-0.876, p = 0.015) and longer DFS (hazard ratio = 0.513, 95% confidence interval: 0.309-0.854, p = 0.010) than resection alone.

CONCLUSIONS

Postoperative radiotherapy using cRT is strongly associated with improved OS and DFS in patients with pT3N0M0 TESCC. A multicenter, randomized phase III clinical trial is warranted to confirm these findings.

High dose radiation with chemotherapy followed by salvage esophagectomy among patients with locally advanced esophageal squamous cell carcinoma

Background

Locoregional failure is a major problem associated with chemoradiation treatment for squamous cell esophageal carcinoma. The aim of this study was to assess the feasibility, efficacy, and toxicity of preoperative radiation (dose > 50 Gy) with platinum‐based chemotherapy followed by esophagectomy in locally advanced squamous cell carcinoma.

Methods

Data of patients with cT2‐cT4 or node positive squamous cell carcinoma of the esophagus who received trimodality treatment between February 2006 and June 2015 were reviewed.

Results

Forty‐four patients were treated with intensity‐modulated radiation therapy, volumetric‐modulated arc therapy or three‐dimensional radiation therapy. The median radiation dose was 60 Gy. The average volume of the lungs receiving 10 Gy was 48.1%, 20 Gy was 24.5%, and the average mean lung dose was 14 Gy. After chemoradiation, R0 resection was achieved in 31 patients (71%). Patients who received >60 Gy had a higher pathologic complete remission rate than those in the lower dose group (59.1% vs. 36.4%). R0 resection and radiation dose >60 Gy were associated with better overall survival in Cox proportional hazards regression analysis. The median follow‐up duration was 22.4 months and median survival was 25.6 months. Two‐year overall, progression‐free survival and locoregional control rates were 55.9%, 28.6%, and 56%, respectively. The most common grade 3–4 toxicities were esophagitis (63.6%) and neutropenia (25%). Grade 3–4 postoperative morbidities included surgical wound infection (2.3%), acute renal failure (2.3%), and anastomosis stricture (2.3%).

Conclusion

Trimodality treatment with a high preoperative radiation dose and chemotherapy yielded a good pathologic complete response rate, and long‐term survival with low toxicities.

Comparison of three-dimensional conformal radiation therapy, intensity-modulated radiation therapy, and volumetric-modulated arc therapy in the treatment of cervical esophageal carcinoma

The aim of this study was to evaluate the effectiveness and toxicities of three-dimensional conformal radiation therapy (3DCRT), intensity-modulated radiation therapy (IMRT), and volumetric-modulated arc therapy (VMAT) in patients with cervical esophageal cancer. Specifically, we asked whether technological advances conferred an advantage with respect to the clinical curative effect. Seventy-eight patients with cervical esophageal cancer treated with definitive radiotherapy with or without concomitant chemotherapy at our institution between 2007 and 2014 were enrolled in the study: 26 received 3DCRT, 30 were treated with IMRT, and 22 underwent VMAT. Kaplan-Meier analysis and the Cox proportional hazard model were used to analyze overall survival (OS) and failure-free survival (FFS). Treatment-related toxicity was also assessed. For all patients, the 2-year OS and FFS rates were 56.2 and 53.9%, respectively. The 2-year OS for the 3DCRT, IMRT, and VMAT groups was 53.6, 55.6, and 60.6%, respectively (P = 0.965). The corresponding 2-year FFS rates were 49.5, 56.7, and 60.1% (P = 0.998). A univariate analysis of the complete response to treatment showed an advantage of treatment modality with respect to OS (P < 0.001). The development of acute hematologic toxicity was not significantly different among the three groups. The survival rates of patients treated with IMRT and VMAT were comparable to the survival of patients administered 3DCRT, while lower lung mean dose, V20, maximum dose of brachial plexus and spinal cord. Grade 1 radiation pneumonitis occurred significantly less in patients treated with IMRT and VMAT than with 3DCRT (P = 0.011). A complete response was the most important prognostic factor of the patients with cervical esophageal cancer.

Advances in Radiotherapy Management of Esophageal Cancer

Radiation therapy (RT) as part of multidisciplinary oncologic care has been marked by profound advancements over the past decades. As part of multimodality therapy for esophageal cancer (EC), a prime goal of RT is to minimize not only treatment toxicities, but also postoperative complications and hospitalizations. Herein, discussion commences with the historical approaches to treating EC, including seminal trials supporting multimodality therapy. Subsequently, the impact of RT techniques, including three-dimensional conformal RT, intensity-modulated RT, and proton beam therapy, is examined through available data. We further discuss existing data and the potential for further development in the future, with an appraisal of the future outlook of technological advancements of RT for EC.

Radiation Dose Escalation in Esophageal Cancer Revisited: A Contemporary Analysis of the National Cancer Data Base, 2004 to 2012

PURPOSE

To evaluate the effect of radiation dose escalation on overall survival (OS) for patients with nonmetastatic esophageal cancer treated with concurrent radiation and chemotherapy.

METHODS AND MATERIALS

Patients diagnosed with stage I to III esophageal cancer treated from 2004 to 2012 were identified from the National Cancer Data Base. Patients who received concurrent radiation and chemotherapy with radiation doses of ≥50 Gy and did not undergo surgery were included. OS was compared using Cox proportional hazards regression and propensity score matching.

RESULTS

A total of 6854 patients were included; 3821 (55.7%) received 50 to 50.4 Gy and 3033 (44.3%) received doses >50.4 Gy. Univariate analysis revealed no significant difference in OS between patients receiving 50 to 50.4 Gy and those receiving >50.4 Gy (P=.53). The dose analysis, binned as 50 to 50.4, 51 to 54, 55 to 60, and >60 Gy, revealed no appreciable difference in OS within any group compared with 50 to 50.4 Gy. Subgroup analyses investigating the effect of dose escalation by histologic type and in the setting of intensity modulated radiation therapy also failed to reveal a benefit. Propensity score matching confirmed the absence of a statistically significant difference in OS among the dose levels. The factors associated with improved OS on multivariable analysis included female sex, lower Charlson-Deyo comorbidity score, private insurance, cervical/upper esophagus location, squamous cell histologic type, lower T stage, and node-negative status (P<.01 for all analyses).

CONCLUSIONS

In this large national cohort, dose escalation >50.4 Gy did not result in improved OS among patients with stage I to III esophageal cancer treated with definitive concurrent radiation and chemotherapy. These data suggest that despite advanced contemporary treatment techniques, OS for patients with esophageal cancer remains unaltered by escalation of radiation dose >50.4 Gy, consistent with the results of the INT-0123 trial. Furthermore, these data highlight that many radiation oncologists have not embraced the concept that dose escalation does not improve OS. Although local control, not investigated in the present study, might benefit from dose escalation, novel therapies are needed to improve the OS of patients with esophageal cancer.

Oesophagus side effects related to the treatment of oesophageal cancer or radiotherapy of other thoracic malignancies

The oesophagus as a serial organ located in the central chest is frequent subject to "incidental" dose application in radiotherapy for several thoracic malignancies including oesophageal cancer itself. Especially due to the radiosensitive mucosa severe radiotherapy induced sequelae can occur, acute oesophagitis and strictures as late toxicity being the most frequent side-effects. In this review we focus on oesophageal side effects derived from treatment of gastrointestinal cancer and secondly provide an overview on oesophageal toxicity from conventional and stereotactic fractionated radiotherapy to the thoracic area in general. Available data on pathogenesis, frequency, onset, and severity of oesophageal side effects are summarized. Whereas for conventional radiotherapy the associations of applied doses to certain volumes of the oesophagus are well described, the tolerance dose to the mediastinal structures for hypofractionated therapy is unknown. The review provides available attempts to predict the risk of oesophageal side effects from dosimetric parameters of SBRT.

Improving Outcomes for Esophageal Cancer using Proton Beam Therapy

Radiation therapy (RT) plays an essential role in the management of esophageal cancer. Because the esophagus is a centrally located thoracic structure there is a need to balance the delivery of appropriately high dose to the target while minimizing dose to nearby critical structures. Radiation dose received by these critical structures, especially the heart and lungs, may lead to clinically significant toxicities, including pneumonitis, pericarditis, and myocardial infarction. Although technological advancements in photon RT delivery like intensity modulated RT have decreased the risk of such toxicities, a growing body of evidence indicates that further risk reductions are achieved with proton beam therapy (PBT). Herein we review the published dosimetric and clinical PBT literature for esophageal cancer, including motion management considerations, the potential for reirradiation, radiation dose escalation, and ongoing esophageal PBT clinical trials. We also consider the potential cost-effectiveness of PBT relative to photon RT.

Individualized radiotherapy by combining high-end irradiation and magnetic resonance imaging

Image-guided radiotherapy (IGRT) has been integrated into daily clinical routine and can today be considered the standard especially with high-dose radiotherapy. Currently imaging is based on MV- or kV-CT, which has clear limitations especially in soft-tissue contrast. Thus, combination of magnetic resonance (MR) imaging and high-end radiotherapy opens a new horizon. The intricate technical properties of MR imagers pose a challenge to technology when combined with radiation technology. Several solutions that are almost ready for routine clinical application have been developed. The clinical questions include dose-escalation strategies, monitoring of changes during treatment as well as imaging without additional radiation exposure during treatment.

The influence of dose distribution on treatment outcome in the SCOPE 1 oesophageal cancer trial

PURPOSE

The first aim of this study was to assess plan quality using a conformity index (CI) and analyse its influence on patient outcome. The second aim was to identify whether clinical and technological factors including planning treatment volume (PTV) volume and treatment delivery method could be related to the CI value.

METHODS AND MATERIALS

By extending the original concept of the mean distance to conformity (MDC) index, the OverMDC and UnderMDC of the 95 % isodose line (50Gy prescribed dose) to the PTV was calculated for 97 patients from the UK SCOPE 1 trial (ISCRT47718479). Data preparation was carried out in CERR, with Kaplan-Meier and multivariate analysis undertaken in EUCLID and further tests in Microsoft Excel and IBM's SPSS.

RESULTS

A statistically significant breakpoint in the overall survival data, independent of cetuximab, was found with OverMDC (4.4 mm, p < 0.05). This was not the case with UnderMDC. There was a statistically significant difference in PTV volume either side of the OverMDC breakpoint (Mann Whitney p < 0.001) and in OverMDC value dependent on the treatment delivery method (mean IMRT = 2.1 mm, mean 3D-CRT = 4.1 mm Mann Whitney p < 0.001). Re-planning the worst performing patients according to OverMDC from 3D-CRT to VMAT resulted in a mean reduction in OverMDC of 2.8 mm (1.6-4.0 mm). OverMDC was not significant in multivariate analysis that included age, sex, staging, tumour type, and position.

CONCLUSION

Although not significant when included in multivariate analysis, we have shown in univariate analysis that a patient's OverMDC is correlated with overall survival. OverMDC is strongly related to IMRT and to a lesser extent with PTV volume. We recommend that VMAT planning should be used for oesophageal planning when available and that attention should be paid to the conformity of the 95 % to the PTV.

Radiation modality use and cardiopulmonary mortality risk in elderly patients with esophageal cancer

BACKGROUND

It is currently unclear whether the superior normal organ-sparing effect of intensity-modulated radiotherapy (IMRT) compared with 3-dimensional radiotherapy (3D) has a clinical impact on survival and cardiopulmonary mortality in patients with esophageal cancer (EC).

METHODS

The authors identified 2553 patients aged > 65 years from the Surveillance, Epidemiology, and End Results (SEER)-Medicare and Texas Cancer Registry-Medicare databases who had nonmetastatic EC diagnosed between 2002 and 2009 and were treated with either 3D (2240 patients) or IMRT (313 patients) within 6 months of diagnosis. The outcomes of the 2 cohorts were compared using inverse probability of treatment weighting adjustment.

RESULTS

Except for marital status, year of diagnosis, and SEER region, both radiation cohorts were well balanced with regard to various patient, tumor, and treatment characteristics, including the use of IMRT versus 3D in urban/metropolitan or rural areas. IMRT use increased from 2.6% in 2002 to 30% in 2009, whereas the use of 3D decreased from 97.4% in 2002 to 70% in 2009. On propensity score inverse probability of treatment weighting-adjusted multivariate analysis, IMRT was not found to be associated with EC-specific mortality (hazard ratio [HR], 0.93; 95% confidence interval [95% CI], 0.80-1.10) or pulmonary mortality (HR, 1.11; 95% CI, 0.37-3.36), but was significantly associated with lower all-cause mortality (HR, 0.83; 95% CI, 0.72-0.95), cardiac mortality (HR, 0.18; 95% CI, 0.06-0.54), and other-cause mortality (HR, 0.54; 95% CI, 0.35-0.84). Similar associations were noted after adjusting for the type of chemotherapy, physician experience, and sensitivity analysis removing hybrid radiation claims.

CONCLUSIONS

In this population-based analysis, the use of IMRT was found to be significantly associated with lower all-cause mortality, cardiac mortality, and other-cause mortality in patients with EC.

Improving target coverage and organ-at-risk sparing in intensity-modulated radiotherapy for cervical oesophageal cancer using a simple optimisation method

PURPOSE

To assess the performance of a simple optimisation method for improving target coverage and organ-at-risk (OAR) sparing in intensity-modulated radiotherapy (IMRT) for cervical oesophageal cancer.

METHODS

For 20 selected patients, clinically acceptable original IMRT plans (Original plans) were created, and two optimisation methods were adopted to improve the plans: 1) a base dose function (BDF)-based method, in which the treatment plans were re-optimised based on the original plans, and 2) a dose-controlling structure (DCS)-based method, in which the original plans were re-optimised by assigning additional constraints for hot and cold spots. The Original, BDF-based and DCS-based plans were compared with regard to target dose homogeneity, conformity, OAR sparing, planning time and monitor units (MUs). Dosimetric verifications were performed and delivery times were recorded for the BDF-based and DCS-based plans.

RESULTS

The BDF-based plans provided significantly superior dose homogeneity and conformity compared with both the DCS-based and Original plans. The BDF-based method further reduced the doses delivered to the OARs by approximately 1-3%. The re-optimisation time was reduced by approximately 28%, but the MUs and delivery time were slightly increased. All verification tests were passed and no significant differences were found.

CONCLUSION

The BDF-based method for the optimisation of IMRT for cervical oesophageal cancer can achieve significantly better dose distributions with better planning efficiency at the expense of slightly more MUs.