Safety of dose escalation by simultaneous integrated boosting radiation dose within the primary tumor guided by (18)FDG-PET/CT for esophageal cancer

Simultaneous integrated boost intensity-modulated radiotherapy (SIB-IMRT) combined with nimotuzumab for locally advanced esophageal squamous cell carcinoma (ESCC): A phase II clinical trial

OBJECTIVE

To evaluate the feasibility, safety and efficacy of concurrent simultaneous integrated boost intensity-modulated radiotherapy (SIB-IMRT) combined with nimotuzumab in the treatment of locally advanced esophageal squamous cell cancer (ESCC).

METHODS

Eligible patients were histologically proven to have locally advanced ESCC, and were unable to tolerate or refuse concurrent chemoradiotherapy (CCRT). Enrolled patients underwent concurrent SIB-IMRT in combination with nimotuzumab.

SIB-IMRT

For the planning target volume of clinical target volume (PTV-C), the prescription dose was 50.4 Gy/28fractions, 1.8 Gy/fraction, 5fractions/week, concurrently, the planning target volume of gross tumor (PTV-G) undergone an integrated boost therapy, with a prescription dose of 63 Gy/28fractions, 2.25 Gy/fraction, 5 fractions/week. Nimotuzumab was administered concurrently with radiotherapy, 200 mg/time, on D1, 8, 15, 22, 29, and 36, with a total accumulation of 1200 mg through intravenous infusion. The primary endpoint of the study was the safety and efficacy of the combined treatment regimen, and the secondary endpoints were 1-year, 2-year, and 3-year local control and survival outcomes.

RESULTS

(1) From December 2018 to August 2021, 35 patients with stage II-IVA ESCC were enrolled and 34 patients completed the full course of radiotherapy and the intravenous infusion of full-dose nimotuzumab. The overall completion rate of the protocol was 97.1%. (2) No grade 4-5 adverse events occurred in the entire group. The most common treatment-related toxicity was acute radiation esophagitis, with a total incidence of 68.6% (24/35). The incidence of grade 2 and 3 acute esophagitis was 25.7% (9/35) and 17.1% (6/35), respectively. The incidence of acute radiation pneumonitis was 8.6% (3/35), including one case each of Grades 1, 2, and 3 pneumonitis. Adverse events in other systems included decreased blood cells, hypoalbuminemia, electrolyte disturbances, and skin rash. Among these patients, five experienced grade 3 electrolyte disturbances during the treatment period (three with grade 3 hyponatremia and two with grade 3 hypokalemia). (3) Efficacy: The overall CR rate was 22.8%, PR rate was 71.4%, ORR rate was 94.2%, and DCR rate was 97.1%.(4) Local control and survival: The 1-, 2-, and 3-year local control (LC) rate, progression-free survival(PFS) rate, and overall survival(OS) rate for the entire group were 85.5%, 75.4%, and 64.9%; 65.7%, 54.1%, and 49.6%; and 77.1%, 62.9%, and 54.5%, respectively.

CONCLUSIONS

The combination of SIB-IMRT and nimotuzumab for locally advanced esophageal cancer demonstrated good feasibility, safety and efficacy. It offered potential benefits in local control and survival. Acute radiation esophagitis was the primary treatment-related toxicity, which is clinically manageable. This comprehensive treatment approach is worthy of further clinical exploration (ChiCTR1900027936).

[18F]FDG-PET-Based Personalized Radiotherapy Dose Prescription

PET imaging with 2'-deoxy-2'-[18F]fluoro-D-glucose ([18F]FDG) has become one of the pillars in the management of malignant diseases. It has proven value in diagnostic workup, treatment policy, follow-up, and as prognosticator for outcome. [18F]FDG is widely available and standards have been developed for PET acquisition protocols and quantitative analyses. More recently, [18F]FDG-PET is also starting to be appreciated as a decision aid for treatment personalization. This review focuses on the potential of [18F]FDG-PET for individualized radiotherapy dose prescription. This includes dose painting, gradient dose prescription, and [18F]FDG-PET guided response-adapted dose prescription. The current status, progress, and future expectations of these developments for various tumor types are discussed.

High-Dose Versus Standard-Dose Intensity-Modulated Radiotherapy With Concurrent Paclitaxel Plus Carboplatin for Patients With Thoracic Esophageal Squamous Cell Carcinoma: A Randomized, Multicenter, Open-Label, Phase 3 Superiority Trial

PURPOSE

The standard dose (SD) of definitive concurrent chemoradiotherapy (dCRT) remains 50.4 Gy in patients with esophageal cancer; a higher dose, when applied with conventional radiation therapy techniques, increases toxicities without improving survival. We investigated whether a high dose of 59.4 Gy using intensity-modulated radiation therapy (IMRT) would improve survival without increasing toxicities.

METHODS

Patients with inoperable thoracic esophageal squamous cell carcinoma (SCC) referred for dCRT were randomly assigned (1:1) to high-dose (HD) IMRT (59.4 Gy) or SD IMRT (50.4 Gy). Chemotherapy consisted of 6 cycles of concurrent weekly paclitaxel and carboplatin and a maximum of 2 cycles of consolidation chemotherapy. Nutritional intervention was implemented for patients with malnutrition on the basis of nutritional screening. The primary endpoint was median overall survival (mOS). Analyses were by modified intention to treat.

RESULTS

Between April 30, 2016, and April 30, 2019, 167 patients were enrolled at 9 participating centers in China. Seventy-one patients in the HD and 73 patients in the SD groups were included in the analysis; 86.8% of the patients completed radiation therapy and 70.1% received 5 or 6 cycles of concurrent chemotherapy. The median follow-up was 36.0 months. The mOS was 28.1 and 26.0 months in the HD and SD arms, respectively (P = .54). A total of 7 treatment-related deaths were observed. Grade 3 or worse treatment-related toxicities were observed in 62% and 68.5% of the patients in the HD and SD arms, respectively (P = .675).

CONCLUSIONS

For patients with inoperable thoracic esophageal SCC, a dose of 59.4 Gy did not improve survival compared with the SD of dCRT using IMRT.

High versus standard radiation dose of definitive concurrent chemoradiotherapy for esophageal cancer: A systematic review and meta-analysis of randomized clinical trials

OBJECTIVES

Compare the efficacy and safety of high vs standard radiation dose of definitive concurrent chemoradiotherapy (dCCRT) for esophageal cancer (EC).

METHODS AND MATERIALS

This meta-analysis is registered in PROSPERO, and it was followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline. Eligible randomized clinical trials (RCTs) comparing high dose (HD;≥59.4 Gy/1.8 Gy) and standard doses (SD; 50 Gy/2Gy or 50.4 Gy/1.8 Gy) were identified on electronic databases. STATA16.0 was used for statistical analysis. A meta-analysis was performed to compare treatment effect and toxicity.

RESULTS

Four articles with a total of 1014 patients were finally included. The results showed that the two groups had similar 1-, 2-, and 3-year OS rates (RR = 1.08, 95 % CI = 0.90-1.30, P = 0.395; RR = 1.07, 95 % CI = 0.95-1.20, P = 0.272; RR = 1.06, 95 % CI = 0.97-1.17, P = 0.184; respectively) and 2-, and 3-year locoregional progression-free survival (LRPFS) (RR = 0.95, 95 % CI = 0.81-1.10, P = 0.478; RR = 0.97, 95 % CI = 0.85-1.11, P = 0.674; respectively). The HD-RT group had higher grade ≥ 3 treatment-related toxicities (OR = 1.35, 95 % CI = 1.03-1.77, P = 0.029) and treatment-related deaths rates (OR = 1.85, 95 % CI = 1.04-3.28, P = 0.036) compared with the SD-RT group. Results of subgroup analysis also indicated that HD could not bring benefit compared to SD, even with modern radiotherapy techniques.

CONCLUSION

SD-RT had similar treatment effect but lower Grade ≥ 3 treatment-related toxicities rates compared with the HD-RT. Therefore, SD (50 Gy/2Gy or 50.4 Gy/1.8 Gy) should be considered as the recommended dose in dCCRT for EC. Further RCTs are needed to verify our conclusions.

Escalation of radiotherapy dose in large locally advanced drug-resistant gastrointestinal stromal tumors by multi-shell simultaneous integrated boost intensity-modulated technique: a feasibility study

BACKGROUND

Resistance to conventional dose schemes and radiotoxicity of healthy tissue is a clinical challenge in the radiation therapy of large locally advanced drug-resistant gastrointestinal stromal tumor (LADR-GIST). This study aimed to assess the feasibility of using multi-shell Simultaneous Integrated Boost Intensity-Modulated modality (SIB-IMRT) strategy to provide a safe and effective escalation dose regimen for LADR-GIST.

METHODS

7 patients with LADR-GIST were selected in this study. The modified SIB-IMRT plans for all patients were generated by delivering different escalation-dose gradients to four ring shaped regions (shells) within the gross tumor volume (GTV). The doses of the central volume of the tumor (GTV_center) were escalated up to 70-92.5 Gy (25 fractions), while the doses of planning target volume (PTV) and shell-1 were kept at 50.0 Gy. Based on different escalation-dose gradients, the modified SIB-IMRT plans were divided into four groups (SIB-IMRT groups). For comparison purposes, plans obtained by conventional IMRT technique (Con-IMRT) with 50 Gy (25 fractions) were also generated for all patients (Con-IMRT group). All plans were normalized to cover 95% of the PTV with the prescribed dose of 50.0 Gy. The equivalent uniform dose (EUD), relative equivalent uniform dose (rEUD), dose volume histogram (DVH), dose profile, conformity index (CI) and monitor unit (MU) were evaluated in five groups. The Friedman Test was performed to determine whether there were significant differences (P < 0.05).

RESULTS

Compared with the Con-IMRT group, the EUD of GTV (EUD_GTV) and rEUD of SIB-IMRT groups were improved when escalation-dose gradient was increased, and the improvement became significant when the escalation-dose gradient reached 20% of the prescription dose. The rEUD tended to be stable as the escalation-dose gradient went up to 25% of the prescription dose. There were no significant differences in CIs and DVH metrics for OARs between the Con-IMRT group and any SIB-IMRT group, but the significant differences were observed between the SIB₁₀-IMRT group and the SIB₂₅-IMRT group. For the SIB-IMRT groups, as the dose gradient became steeper in the dose profiles, the higher dose was mainly accumulated in the inner part of GTV accompanied with a higher MU.

CONCLUSIONS

The proposed multi-shell SIB-IMRT strategy is feasible in dosimetry for LADR-GIST and can acquire higher therapeutic gain without sacrifice of healthy tissues. It appears that the scheme of delivering 20% of the prescribed escalation-dose gradient to the target volume can provide satisfactory dose irradiation for LADR-GIST, and it should be evaluated in future clinical study.

A combined predicting model for benign esophageal stenosis after simultaneous integrated boost in esophageal squamous cell carcinoma patients (GASTO1072)

Purpose

We aimed to develop a combined predicting model for benign esophageal stenosis (BES) after simultaneous integrated boost (SIB) with concurrent chemotherapy in patients with esophageal squamous cell carcinoma (ESCC).

Methods

This study included 65 patients with EC who underwent SIB with chemotherapy. Esophageal stenosis was evaluated using esophagograms and the severity of eating disorders. Risk factors were investigated using univariate and multivariate analyses. Radiomics features were extracted based on contrast-enhanced CT (CE-CT) before treatment. The least absolute shrinkage and selection operator (LASSO) regression analysis was used for feature selection and radiomics signature construction. The model’s performance was evaluated using Harrell’s concordance index and receiver operating characteristic curves.

Results

The patients were stratified into low- and high-risk groups according to BES after SIB. The area under the curves of the clinical model, Rad-score, and the combined model were 0.751, 0.820 and 0.864, respectively. In the validation cohort, the AUCs of these three models were 0.854, 0.883 and 0.917, respectively. The Hosmer-Lemeshow test showed that there was no deviation from model fitting for the training cohort (p=0.451) and validation cohort (p=0.481). The C-indexes of the nomogram were 0.864 and 0.958 for the training and validation cohort, respectively. The model combined with Rad-score and clinical factors achieved favorable prediction ability.

Conclusion

Definitive chemoradiotherapy could alleviate tumor-inducing esophageal stenosis but result in benign stenosis. We constructed and tested a combined predicting model for benign esophageal stenosis after SIB. The nomogram incorporating both radiomics signature and clinical prognostic factors showed favorable predictive accuracy for BES in ESCC patients who received SIB with chemotherapy.

Trial registration number and date of registration

Registered in www.Clinicaltrial.gov, ID: NCT01670409, August 12, 2012

Effect of Adjuvant Radiation Dose on Survival in Patients with Esophageal Squamous Cell Carcinoma

Background: For patients with esophageal squamous cell carcinoma (ESCC) treated with surgery alone, the incidence of local-regional recurrence remains unfavorable. Postoperative radiotherapy (PORT) has been associated with increased local-regional recurrence-free survival (LRFS), although its application is limited by concerns of PORT-related toxicities. Methods: Among 3591 patients with ESCC analyzed in this study, 2765 patients with T3-4N0 and T1-4N1-3 lesions and specific local-regional status information were analyzed in a subsequent analysis of adjuvant radiation dose (aRTD) effect. Application of the restricted cubic spline regression model revealed a non-linear relationship between aRTD and survival/radiotoxicity. Linear regression analysis (LRA) was performed to evaluate correlations between LRFS and overall survival (OS)/ disease-free survival (DFS). Results: For patients staged T1−2N0, T1−2N1−3, T3−4N0, and T3−4N1−3, 5-year OS in PORT and non-PORT groups were 77.38% vs. 72.91%, p = 0.919, 52.35% vs. 46.60%, p = 0.032, 73.41% vs. 61.19%, p = 0.005 and 38.30% vs. 25.97%, p < 0.001. With aRTD escalation, hazard ratios (HRs) of OS/DFS declined until aRTD exceeded 50Gy, then increased, whereas that of LRFS declined until aRTD exceeded 50 Gy, then remained steady. HR of treatment-related mortality was stable until aRTD exceeded 50 Gy, then increased. LRA revealed strong correlations between LRFS and OS/DFS (r = 0.984 and r = 0.952, respectively). An absolute 1% advancement in LRFS resulted in 0.32% and 0.34% improvements in OS and DFS. Conclusions: An aRTD of 50Gy was well-tolerated, with favorable survival resulting from PORT-related LRFS improvement in patients staged T3−4N0 or T1-4N1−3. Further stratification analyses based on tumor burden would help determine potential PORT-beneficiaries.

Radiation Dose-Effect Relation in Patients with Esophageal Squamous Cell Carcinoma: A National Cancer Center Data and Literature-Based Analysis

Introduction

Despite receiving definitive chemoradiotherapy (dCRT) with radiation dose (RTD) of 50.4 Gy, survival of esophageal carcinoma was dismal. The effect of RTD in cancer control and radiotoxicity, and the extent to which local-regional control (LRC) influenced survival remain vague. This study aimed at evaluating RTD-effect relationship in esophageal squamous cell carcinoma (ESCC).

Methods

1440 dRT/CRT-treated ESCC patients were enrolled. Restricted cubic spline regression model was applied to reveal nonlinear relationship between RTD and survival/radiotoxicity. Linear regression analysis (LRA) was performed to evaluate correlations between LRC and overall survival (OS) or progression-free survival (PFS).

Results

For 1440 dRT/CRT-treated ESCC patients, with RTD escalating, hazard ratios (HRs) of OS, PFS, LRC declined until RTD exceeded 60 Gy, then increased. HR of treatment-related mortality was stable until RTD exceeded 60 Gy, then increased. HR of LRC was lower for majority of patients treated with RTD≥60 Gy, except for those with KPS<80, T1-2 lesion, or without lymph node metastasis. LRA revealed strong correlations between LRC and OS/PFS. 45.5% and 44.9% of OS and PFS improvements were owing to improved LRC.

Conclusions

RTD of 60 Gy was well tolerated, with favorable survival resulted of LRC improvement in local-advanced ESCC. Further stratification analyses based on radiation sensitivity will be helpful to determine potential beneficiaries of RTD escalation.

[Dose-escalated radiotherapy in esophageal cancer: A review of the literature]

For non-operable, localized esophageal cancer, definitive concurrent chemoradiotherapy is the standard treatment. Currently, the radiation dose recommended is 50 to 50,4Gy. However, the optimal radiation dose remains controversial. Many studies have demonstrated that locoregional failure remains a common failure pattern, most likely to occur within the original gross tumor volume. Several retrospective studies have indicated that higher radiation dose may improve local control and survival while others failed to demonstrate improved oucomes. In three randomized trials (INT0123, ARTDECO, and CONCORDE), dose escalation did not improve locoregional control nor survival, establishing 50Gy as the standard chemoradiation dose for patients who will not undergo surgery. Here, we reviewed the results of dose escalation in the literature in the neoadjuvant and definitive settings.

Prognostic factors for 495 nonoperative esophageal squamous cancer patients receiving IMRT plus chemotherapy: A retrospective analysis

PURPOSE

Chemoradiotherapy is regarded as a standard scheme for inoperable and unresectable esophageal cancers. Our aims were to explore the prognostic factors relevant to esophageal squamous cell carcinoma (ESCC) following intensity-modulated radiation therapy (IMRT) plus chemotherapy.

MATERIAL AND METHODS

Totally 495 ESCC patients undergoing IMRT combined with chemotherapy in our hospital between 2011 and 2020 were retrospectively analyzed. Potential clinical prognosis-related factors were assessed by uni- and multivariate analyses.

RESULTS

The median overall survival (OS) and progression-free survival (PFS) of the ESCC patients were 2.25 and 1.24years, respectively. Uni- and multivariate analyses demonstrated the relevant independent prognostic factors of OS and PFS were gender, T stage, N stage, clinical stage, and tumor location (P<0.05), but not chemotherapy or radiotherapy dose. We further compared the 5-year OS rates among different T stages, N stages, clinical stages, genders, and tumor locations. The survival rate at the higher clinical stage was significantly lower (P<0.001). The 5-year OS in the upper thorax of the tumor was 46.0% and exceeded other tumor locations (P<0.05). The 5-year OS was 56.1% among females and 33.3% among males (P=0.001).

CONCLUSIONS

For ESCC patients receiving IMRT combined with chemotherapy, their long-term curative effects are influenced by T stages, N stages, clinical stages, genders, and tumor locations. ESCC patients who are females, or have upper thoracic tumor, or are at early clinical stage own better prognosis.

Dose escalation based on 18F-FDG PET/CT response in definitive chemoradiotherapy of locally advanced esophageal squamous cell carcinoma: a phase III, open-label, randomized, controlled trial (ESO-Shanghai 12)

INTRODUCTION

Definitive chemoradiotherapy has established the standard non-surgical treatment for locally advanced esophageal cancer. The standard dose of 50-50.4 Gy has been established decades ago and been confirmed in modern trials. The theorical advantage of better local control and technical advances for less toxicity have encouraged clinicians for dose escalation investigation. ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography/computed tomography (PET/CT) have the potential to tailor therapy for esophageal patients not showing response to CRT and pioneers the PET-based dose escalation.

METHODS AND ANALYSIS

The ESO-Shanghai 12 trial is a prospective multicenter randomized phase 3 study in which patients are randomized to either 61.2 Gy or 50.4 Gy of radiation dose by PET response. Both groups undergo concurrent chemoradiotherapy with paclitaxel/cisplatin regimen for 2 cycles followed by consolidation chemotherapy for 2 cycles. Patients with histologically confirmed ESCC [T1N1-3M0, T2-4NxM0, TxNxM1 (Supraclavicular lymph node metastasis only), (AJCC Cancer Staging Manual, 8th Edition)] and without any prior treatment of chemotherapy, radiotherapy or surgery against esophageal cancer will be eligible. The primary endpoints included overall survival in PET/CT non-responders (SUV_max > 4.0) and overall survival in total population. Patients will be stratified by standardized uptake volume, gross tumor volume and tumor location. The enrollment could be ended, when the number of PET/CT non-responder reached 132 and the total population reached 646 for randomization.

ETHICS AND DISSEMINATION

This trial has been approved by the Fudan University Shanghai Cancer Center Institutional Review Board. Trial results will be disseminated via peer reviewed scientific journals and conference presentations. Trial registration The trial was initiated in 2018 and is currently recruiting patients. Trial registration number NCT03790553.

A Phase III Multicenter Randomized Clinical Trial of 60 Gy versus 50 Gy Radiation Dose in Concurrent Chemoradiotherapy for Inoperable Esophageal Squamous Cell Carcinoma

PURPOSE

In this multicenter phase 3 trial, the efficacy and safety of 60 Gy and 50 Gy doses delivered with modern radiotherapy technology for definitive concurrent chemoradiotherapy (CCRT) in patients with inoperable esophageal squamous cell carcinoma (ESCC) were evaluated.

PATIENTS AND METHODS

Patients with pathologically confirmed stage IIA‒IVA ESCC were randomized 1:1 to receive conventional fractionated 60 Gy or 50 Gy to the tumor and regional lymph nodes. Concurrent weekly chemotherapy (docetaxel 25 mg/m2; cisplatin 25 mg/m2) and two cycles of consolidation chemotherapy (docetaxel 70 mg/m2; cisplatin 25 mg/m2 days 1‒3) were administered.

RESULTS

A total of 319 patients were analyzed for survival, and the median follow-up was 34.0 months. The 1- and 3-year locoregional progression-free survival (PFS) rates for the 60 Gy group were 75.6% and 49.5% versus 72.1% and 48.4%, respectively, for the 50 Gy group [HR, 1.00; 95% confidence interval (CI), 0.75‒1.35; P = 0.98]. The overall survival rates were 83.7% and 53.1% versus 84.8% and 52.7%, respectively (HR, 0.99; 95% CI, 0.73‒1.35; P = 0.96), whereas the PFS rates were 71.2% and 46.4% versus 65.2% and 46.1%, respectively (HR, 0.97; 95% CI, 0.73‒1.30; P = 0.86). The incidence of grade 3+ radiotherapy pneumonitis was higher in the 60 Gy group (nominal P = 0.03) than in the 50 Gy group.

CONCLUSIONS

The 60 Gy arm had similar survival endpoints but a higher severe pneumonitis rate compared with the 50 Gy arm. Fifty Gy should be considered as the recommended dose in CCRT for ESCC.

Comparison of efficacy and safety between simultaneous integrated boost intensity-modulated radiotherapy and standard-dose intensity-modulated radiotherapy in locally advanced esophageal squamous cell carcinoma: a retrospective study

Objective

This study aimed to evaluate the efficacy and safety of simultaneous integrated boost intensity-modulated radiotherapy (SIB-IMRT) versus standard-dose intensity-modulated radiotherapy (SD-IMRT) in the treatment of locally advanced esophageal squamous cell carcinoma.

Methods

From July 2003 to March 2014, 1748 patients in a single center who received definitive chemoradiotherapy were included in the analysis. A total of 109 patients who underwent SIB-IMRT and fulfilled all inclusion and exclusion criteria were identified as the study group. A total of 266 patients who underwent SD-IMRT (60 Gy/30 fractions, 2 Gy/fraction, 1 time/day, 5 times/week) during the same period were selected as the control group. Propensity score matching (PSM) was used to balance the baseline characteristics. Survival status, treatment failure mode, and the occurrence of adverse events were compared between the two groups.

Results

There were more women and more cervical and upper thoracic cancers (P = 0.038, < 0.001, respectively) in the SIB-IMRT group before case matching. The median progression-free survival (PFS) in the SD-IMRT and SIB-IMRT groups was 22 and 19 months, respectively, and the median overall survival duration was 24 and 22 months, respectively, with χ² = 0.244 and P = 0.621. After PSM of 1:1, 138 patients entered the final analysis (69 cases from each group). The median PFS of the SD-IMRT group and the SIB-IMRT group was 13 and 18 months, respectively, with χ² = 8.776 and P = 0.003. The 1‑, 3‑, and 5‑year overall survival rates were 66.7, 21.7, and 8.7% and 65.2, 36.2, and 27.3%, respectively, and the median overall survival duration was 16 and 22 months, respectively, with χ² = 5.362 and P = 0.021. Treatment failure mode: 5‑year local regional recurrence rates of SD-IMRT and SIB-IMRT were 50.7 and 36.2%, respectively, with χ² = 2.949 and P = 0.086. The 5‑year distant metastasis rates of the two groups were 36.2 and 24.6%, respectively, with χ² = 2.190 and P = 0.139. Adverse events: 3 patients experienced grade 4–5 toxicity (2.2%), including one case of grade 4 radiation esophagitis and two cases of grade 5 radiation pneumonitis, all in the SD-IMRT group; 14 patients experienced grade 3 adverse events (10.1%), primarily including radiation esophagitis, radiation pneumonitis, and hematological toxicity.

Conclusion

The technique of SIB-IMRT was safe and reliable compared with SD-IMRT. In addition, SIB-IMRT had locoregional control advantages and potential survival benefits.

Supplementary Information

The online version of this article (10.1007/s00066-021-01894-y) contains supplementary material, which is available to authorized users.

Radiotherapy for cancers of the oesophagus, cardia and stomach

We present the updated recommendations of the French society for radiation oncology on radiotherapy of oesophageal cancer. Oesophageal cancer still remains a malignant tumour with a poor prognosis. Surgery remains the standard treatment for localized cancers, regardless of histology. For locally advanced stages, surgery remains a standard for adenocarcinomas after neoadjuvant treatment with chemotherapy or chemoradiotherapy. However, it is a therapeutic option after initial chemoradiotherapy for stage III squamous cell carcinomas, given the increased morbidity and mortality with a multimodal treatment, which results in an equivalent overall survival with or without surgery. Preoperative or exclusive chemoradiotherapy should be delivered according to validated regimens with an effective total dose (50Gy), if surgery is not planned or if the tumour is deemed resectable before chemoradiotherapy. Intensity-modulated radiotherapy significantly reduces irradiation of the lungs and heart and may reduce the morbidity of this treatment, especially in combination with surgery. In case of exclusive chemoradiotherapy, dose escalation beyond 50Gy is not currently recommended. Some technical considerations still remain questionable, such as the place of prophylactic lymph node irradiation, adaptive radiotherapy, evaluation of response during and after chemoradiotherapy and the value of proton therapy.

Geometrical Comparison and Quantitative Evaluation of 18F-FDG PET/CT- and DW-MRI-Based Target Delineation Before and During Radiotherapy for Esophageal Squamous Carcinoma

Background and Purpose

This study aimed to evaluate the geometrical differences in and metabolic parameters of ¹⁸F-fluorodeoxyglucose positron emission tomography–computed tomography (¹⁸F-FDG PET-CT) and diffusion-weighted magnetic resonance imaging (DW-MRI) performed before and during radiotherapy (RT) for patients with esophageal cancer based on the three-dimensional CT (3DCT) medium and explore whether the high signal area derived from DW-MRI can be used as a tool for an individualized definition of the volume in need of dose escalation for esophageal squamous cancer.

Materials and Methods

Thirty-two patients with esophageal squamous cancer sequentially underwent repeated 3DCT, ¹⁸F-FDG PET-CT, and enhanced MRI before the initiation of RT and after the 15th fraction. All images were fused with 3DCT images through deformable registration. The gross tumor volume (GTV) was delineated based on PET Edge on the first and second PET-CT images and defined as GTV_PETpre and GTV_PETdur, respectively. GTV_DWIpre and GTV_DWIdur were delineated on the first and second DWI and corresponding T₂-weighted MRI (T₂W-MRI)-fused images. The maximum, mean, and peak standardized uptake values (SUVs; SUV_max, SUV_mean, and SUV_peak, respectively); metabolic tumor volume (MTV); and total lesion glycolysis(TLG) and its relative changes were calculated automatically on PET. Similarly, the minimum and mean apparent diffusion coefficient (ADC; ADC_min and ADC_mean) and its relative changes were measured manually using ADC maps.

Results

The volume of GTV_CT exhibited a significant positive correlation with that of GTV_PET and GTV_DWI (both p < 0.001). Significant differences were observed in both ADCs and ¹⁸F-FDG PET metabolic parameters before and during RT (both p < 0.001). No significant correlation was observed between SUVs and ADCs before and during RT (p = 0.072–0.944) and between ∆ADCs and ∆SUVs (p = 0.238–0.854). The conformity index and degree of inclusion of GTV_PETpre to GTV_DWIpre were significantly higher than those of GTV_PETdur to GTV_DWIdur (both p < 0.001). The maximum diameter shrinkage rate (∆LD_DWI) (24%) and the tumor volume shrinkage rate (VRR_DWI) (60%) based on DW-MRI during RT were significantly greater than the corresponding PET-based ∆LD_PET (14%) and VRR_PET (41%) rates (p = 0.017 and 0.000, respectively).

Conclusion

Based on the medium of CT images, there are significant differences in spatial position, biometabolic characteristics, and the tumor shrinkage rate for GTVs derived from ¹⁸F-FDG PET-CT and DW-MRI before and during RT for esophageal squamous cancer. Further studies are needed to determine if DW-MRI will be used as tool for an individualized definition of the volume in need of dose escalation.

Definitive Simultaneous Integrated Boost Versus Conventional-Fractionated Intensity Modulated Radiotherapy for Patients With Advanced Esophageal Squamous Cell Carcinoma: A Propensity Score-Matched Analysis

BACKGROUND

The aim of this study was to compare the effects of simultaneous integrated boost-intensity modulated radiotherapy (SIB-IMRT) and conventional fractionated-IMRT (CF-IMRT) for patients with esophageal squamous cell carcinoma (ESCC).

METHODS

The data of 1173 patients treated with either CF-IMRT or SIB-IMRT for a curative intent from 2005 to 2016 were retrospectively reviewed. Propensity score matching (PSM) was used to create a well-balanced cohort of 687 patients at 1:2 ratio (237 patients in SIB-IMRT group and 450 patients in CF-IMRT group). Overall survival (OS), progression-free survival (PFS), recurrence pattern, and toxicity profiles were evaluated and compared between the two groups after PSM.

RESULTS

After a median follow-up time of 42.3 months (range, 3.0-153.2 months) for surviving patients, survival results were comparable in the two groups. After PSM, the 1-year, 2-year and 4-year OS rates in the SIB-IMRT and CF-IMRT groups were 70.0% vs. 66.4%, 41.9% vs. 41.7% and 30.2% vs. 27.6%, respectively (p = 0.87). The 1-year, 2-year and 4-year PFS rates were 48.4% vs. 49.1%, 31.2% vs. 29.4%, and 26.1% vs. 17.9%, respectively (p = 0.64). Locoregional recurrence (p = 0.32) and distant metastasis (p = 0.54) rates were also comparable between two groups. The toxicity profile was similar in the two groups. Multivariate analyses in the matched samples showed that female, concurrent chemotherapy and earlier clinical stage were independently associated with longer OS and PFS.

CONCLUSIONS

SIB-IMRT appears to be equivalent to CF-IMRT in treatment efficacy and safety, and could become an alternative option for definitive radiotherapy of ESCC.

Results of a Phase 1/2 Trial of Chemoradiotherapy With Simultaneous Integrated Boost of Radiotherapy Dose in Unresectable Locally Advanced Esophageal Cancer

Importance

Effective treatment options for locally advanced esophageal cancer are limited, and rates of local recurrence after standard chemoradiotherapy remain high.

Objective

To evaluate toxic effects, local control, and overall survival rates after chemoradiotherapy with a simultaneous integrated boost of radiotherapy dose to the gross tumor and nodal disease for patients with unresectable locally advanced esophageal cancer.

Design, Setting, and Participants

A phase 1/2, single-arm trial was conducted in 46 patients from April 28, 2010, to April 9, 2015 (median follow-up, 52 months [range, 2-86 months]), at a tertiary academic cancer center. Outcomes of the study patients were compared with those of 97 similar patients treated at the same institution from January 10, 2010, to December 5, 2014, as part of the interim analysis. Statistical analysis was performed from December 15, 2018, to February 12, 2019.

Interventions

Chemoradiotherapy with a simultaneous integrated boost of radiotherapy dose (50.4 Gy to subclinical areas at risk and 63.0 Gy to the gross tumor and involved nodes, all given in 28 fractions) with concurrent docetaxel and capecitabine or fluorouracil.

Main Outcomes and Measures

Toxic effects, local (in-field) control, and overall survival rates.

Results

All 46 patients (11 women and 35 men; median age, 65.5 years [range, 37.3-84.4 years]) received per-protocol therapy, as intensity-modulated photon therapy (39 [85%]) or intensity-modulated proton therapy (7 [15%]); 11 patients (24%) ultimately underwent resection. No patients experienced grade 4 or 5 toxic effects; the 10 acute grade 3 toxic events were esophagitis (4), dysphagia (3), and anorexia (3) and the 3 late grade 3 toxic events were all esophageal strictures. The actuarial local recurrence rates were 22% (95% CI, 11%-35%) at 6 months, 30% (95% CI, 18%-44%) at 1 year, and 33% (95% CI, 20%-46%) at 2 years. Overall, 15 patients (33%) experienced local failure, at a median interval of 5 months (range, 1-24 months). The median overall survival time was 21.5 months (range, 2.3-86.4 months). Exploratory comparison with a 97-patient contemporaneous institutional cohort receiving standard-dose (non-simultaneous integrated boost) chemoradiotherapy showed superior local control (hazard ratio, 0.49; 95% CI, 0.26-0.92; P = .03) and overall survival (hazard ratio, 0.66; 95% CI, 0.47-0.94; P = .02) in the group that received chemoradiotherapy with a simultaneous integrated boost.

Conclusions and Relevance

These findings suggest that chemoradiotherapy with a simultaneous integrated boost of radiotherapy dose for locally advanced esophageal cancer is well tolerated, with encouraging local control, and thus warrants further study.

Trial Registration

ClinicalTrials.gov identifier: NCT01102088.

Effect of SIB-IMRT-based selective dose escalation of local tumor on the prognosis of patients with esophageal cancer

BACKGROUND

To investigate the effect of SIB-IMRT-based selective dose escalation to local tumor on the prognosis of patients with esophageal cancer (EC).

METHODS

A total of 302 EC patients were enrolled. The prognostic factors of the entire group were initially analyzed, and the composition ratios of the two groups and the different doses of each fraction for PTV were compared. The propensity-score matching (PSM) was carried out (1:1 ratio), and the prognostic factors for the two groups were analyzed according to the results of COX.

RESULTS

The median overall survival (OS) for all patients was 30.0 months (23.495-36.505 months), and the median disease-free survival (DFS) was 21.3 months (7.698-24.902 months). In multivariate analysis, chemotherapy, cTNM stage and dose-per-fraction for the PTV were independent prognostic factors for OS (P = 0.013, 0.000, 0.028) and DFS (P = 0.033, 0.000, 0.047). Multivariate analysis of patients after PSM revealed that cTNM staging and dose-per-fraction were the independent prognostic factors for OS (P = 0.000, 0.015). Chemotherapy, cTNM staging and dose-per-fraction for the PTV were the independent prognostic factors for DFS (P = 0.025, 0.010, 0.015). There was no significant difference in grade ≥ 2 acute toxicities between the two groups. A subgroup analysis of patients with a single dose of 2 Gy and > 2 Gy in the SIB-IMRT group showed that OS and DFS of the latter were significantly better than those of the former.

CONCLUSION

The selective dose escalation to local tumors based on SIB-IMRT technique can improve the survival of patients received radical radiotherapy without increasing toxicities.

Concurrent chemoradiotherapy versus radiotherapy alone for patients with locally advanced esophageal squamous cell carcinoma in the era of intensity modulated radiotherapy: a propensity score-matched analysis

Background

To investigate the survival benefit of concurrent chemoradiotherapy (CCRT) for patients with locally advanced esophageal squamous cell carcinoma (ESCC) during the years of intensity‐modulated radiotherapy (IMRT).

Methods

Medical records of 1089 patients with ESCC who received IMRT from January 2005 to December 2017 were retrospectively reviewed. A total of 617 patients received CCRT, 472 patients received radiotherapy (RT) alone. Propensity score matching (PSM) method was used to eliminate baseline differences between the two groups. Survival and toxicity profile were evaluated afterward.

Results

After a median follow‐up time of 47.9 months (3.2–149.8 months), both overall survival (OS) and progression‐free survival (PFS) of the CCRT group were better than those of the RT alone group, either before or after PSM. After PSM, the 1‐, 3‐, and 5‐year OS of RT alone and CCRT groups were 59.0% versus 70.2%, 27.7% versus 40.5% and 20.3% versus 33.1%, respectively (p < 0.001). The 1‐, 3‐, and 5‐year PFS were 39.4% versus 49.0%, 18.3% versus 30.4% and 10.5% versus 25.0%, respectively (p < 0.001). The rates of ≥ grade 3 leukopenia and radiation esophagitis in the CCRT group were higher than that of RT alone group (p < 0.05). There was no significant difference in the probability of radiation pneumonitis between the two groups (p = 0.167). Multivariate Cox analysis indicated that female, EQD2 ≥60 Gy and concurrent chemotherapy were favorable prognostic factors for both OS and PFS.

Conclusions

Concurrent chemotherapy can bring survival benefits to patients with locally advanced ESCC receiving IMRT. For patients who cannot tolerate concurrent chemotherapy, RT alone is an effective alternative with promising results.

Motion-compensated FDG PET/CT for oesophageal cancer

PURPOSE

Respiratory-induced motion of oesophageal tumours and lymph nodes can influence positron-emission tomography/computed tomography (PET/CT). The aim was to compare standard three-dimensional (3D) and motion-compensated PET/CT regarding standardized uptake value (SUV), metabolic tumour volume (MTV) and detection of lymph node metastases.

METHODS

This prospective observational study (NCT02424864) included 37 newly diagnosed oesophageal cancer patients. Diagnostic PET/CT was reconstructed in 3D and motion-compensated PET/CT. MTVs of the primary tumour were calculated using an automated region-growing algorithm with SUV thresholds of 2.5 (MTV2.5) and ≥ 50% of SUVmax (MTV50%). Blinded for reconstruction method, a nuclear medicine physician assessed all lymph nodes showing ¹⁸F‑fluorodeoxyglucose uptake for their degree of suspicion.

RESULTS

The mean (95% CI) SUVmax of the primary tumour was 13.1 (10.6-15.5) versus 13.0 (10.4-15.6) for 3D and motion-compensated PET/CT, respectively. MTVs were also similar between the two techniques. Bland-Altman analysis showed mean differences between both measurements (95% limits of agreement) of 0.08 (-3.60-3.75), -0.26 (-2.34-1.82), 4.66 (-29.61-38.92) cm³ and -0.95 (-19.9-18.0) cm³ for tumour SUVmax, lymph node SUVmax, MTV2.5 and MTV50%, respectively. Lymph nodes were classified as highly suspicious (30/34 nodes), suspicious (20/22) and dubious (66/59) for metastases on 3D/motion-compensated PET/CT. No additional lymph node metastases were found on motion-compensated PET/CT. SUVmax of the most intense lymph nodes was similar for both scans: mean (95% CI) 6.6 (4.3-8.8) and 6.8 (4.5-9.1) for 3D and motion-compensated, respectively.

CONCLUSION

SUVmax of the primary oesophageal tumour and lymph nodes was comparable on 3D and motion-compensated PET/CT. The use of motion-compensated PET/CT did not improve lymph node detection.

Long-term follow-up of a phase I/II trial of radiation dose escalation by simultaneous integrated boost for locally advanced esophageal squamous cell carcinoma

BACKGROUND

To observe the long-term survival and late adverse events in a phase Ⅰ/Ⅱ trial (NCT01843049) of dose escalation for thoracic esophageal squamous cell carcinoma (ESCC) with simultaneous integrated boost (SIB) technique.

METHODS

Patients with ESCC were treated with escalating radiation dose of four predefined levels. Dose of 62.5-64 Gy/25-32 fractions was delivered to the gross tumor volume (GTV), with (Level 3&4) or without (Level 1&2) a SIB up to 70 Gy for pre-treatment 50% SUVmax area of GTV. Patients also received 2 cycles of chemotherapy of cisplatin and fluorouracil concurrently and 2 more cycles after radiotherapy.

RESULTS

Median follow-up duration was 17.2 (2.5-83.4) months for all 44 patients and 47.2 (3.9-83.4) months for 25 survivors. The 3-year overall survival and progression-free survival rates were 57.6% and 41.0%, respectively. One, one, four and twelve severe (grade≥3) esophageal late adverse events (SEAE) occurred in patients of Level 1/2/3/4 (n = 5/10/16/13), with median occurrence time of 6.5 months. In univariable and multivariable competing risk models, maximal dose of the esophagus (Dmax) was found to have significant impact on the incidence of SEAE, and the cutoff distinguishing patients who developed SEAE or not was 77 Gy.

CONCLUSION

Boosting the gross tumor to 63 Gy while delivering 50.4 Gy to subclinical diseases in 28 fractions in locally advanced ESCC is well tolerated with promising long-term survival. Intenser dose regimen should be considered with caution before further toxicity assessment. Esophageal Dmax was significantly associated with severe late esophageal injury, while more findings of dose-volume predictors need larger-sample investigation.

Review of MR-Guided Radiotherapy for Esophageal Cancer

In this review, we outline the potential benefits and the future role of MRI and MR-guided radiotherapy (MRgRT) in the management of esophageal cancer. Although not currently used in most clinical practice settings, MRI is a useful non-invasive imaging modality that provides excellent soft tissue contrast and the ability to visualize cancer physiology. Chemoradiation therapy with or without surgery is essential for the management of locally advanced esophageal cancer. MRI can help stage esophageal cancer, delineate the gross tumor volume (GTV), and assess the response to chemoradiotherapy. Integrated MRgRT systems can help overcome the challenge of esophageal motion due to respiratory motion by using real-time imaging and tumor tracking with respiratory gating. With daily on-table MRI, shifts in tumor position and tumor regression can be taken into account for online-adaptation. The combination of accurate GTV visualization, respiratory gating, and online adaptive planning, allows for tighter treatment volumes and improved sparing of the surrounding normal organs. This could lead to a reduction in radiotherapy induced cardiac toxicity, pneumonitis and post-operative complications. Tumor physiology as seen on diffusion weighted imaging or dynamic contrast enhancement can help individualize treatments based on the response to chemoradiotherapy. Patients with a complete response on MRI can be considered for organ preservation while patients with no response can be offered an earlier resection. In patients with a partial response to chemoradiotherapy, areas of residual cancer can be targeted for dose escalation. The tighter and more accurate targeting enabled with MRgRT may enable hypofractionated treatment schedules.

Late Toxicities, Failure Patterns, Local Tumor Control, and Survival of Esophageal Squamous Cell Carcinoma Patients After Chemoradiotherapy With a Simultaneous Integrated Boost: A 5-Year Phase II Study

PURPOSE

We aimed to evaluate the long-term outcomes of concurrent chemoradiotherapy (CCRT) with a simultaneous integrated boost (SIB) of radiotherapy for esophageal squamous cell carcinoma (ESCC).

METHODS AND MATERIALS

Eighty-seven patients with primary ESCC enrolled in this phase II trial. The majority (92.0%) had locoregionally advanced disease. They underwent definitive chemoradiotherapy. The radiotherapy doses were 66 Gy for the gross tumor and 54 Gy for the subclinical disease. Doses were simultaneously administered in 30 fractions over 6 weeks. The patients also underwent concurrent and adjuvant chemotherapy, which comprised cisplatin and fluorouracil. The study end points were acute and late toxicities, first site of failure, locoregional tumor control, and overall survival rates.

RESULTS

The median follow-up time was 65.7 (range, 2.2-97.5) months for all patients and 81.5 (range, 19.4-97.5) months for those alive. There were 17 cases (19.5%) of severe late toxicities, including four cases (4.6%) of grade 5 and seven (8.0%) of grade 3 esophageal ulceration, four (4.6%) of grade 3 esophageal stricture, and two (2.3%) of grade 3 radiation-induced pneumonia. Twenty-three (26.4%) patients had locoregional disease progression. Most (86.7%) locally progressive lesions were within the dose-escalation region in the initial radiation plan, while majority of the recurrent lymph nodes were found out-of-field (83.3%) and in the supraclavicular region (75.0%). The 1-, 2-, 3-, and 5-year locoregional tumor control and overall survival rates were 79.2%, 72.4%, 72.4%, 70.8%, and 82.8%, 66.6%, 61.9%, 58.4%, respectively. Incomplete tumor response, which was assessed immediately after CCRT was an independent risk predictor of disease progression and death in ESCC patients.

CONCLUSIONS

CCRT with SIB was well tolerated in ESCC patients during treatment and long-term follow-up. Moreover, patients who underwent CCRT with SIB exhibited improved local tumor control and had better survival outcomes compared to historical data of those who had standard-dose radiotherapy.

A multicenter prospective phase III clinical randomized study of simultaneous integrated boost intensity-modulated radiotherapy with or without concurrent chemotherapy in patients with esophageal cancer: 3JECROG P-02 study protocol

BACKGROUND

Since the development of three-dimensional conformal radiotherapy and intensity-modulated radiotherapy (IMRT), no prospective study has investigated whether concurrent chemoradiotherapy (SIB-IMRT with 60 Gy) remains superior to radiotherapy (SIB-IMRT) alone for unresectable esophageal cancer (EC). Furthermore, the optimal therapeutic regimen for patients who cannot tolerate concurrent chemoradiotherapy is unclear. We recently completed a phase I/II radiation dose-escalation trial using simultaneous integrated boost (SIB), elective nodal irradiation, and concurrent chemotherapy for unresectable EC. We now intend to conduct a prospective, phase III, randomized study of SIB-IMRT with or without concurrent chemotherapy. We aim to find a safe, practical, and effective therapeutic regimen to replace the conventional segmentation (1.8-2.0 Gy) treatment mode (radiotherapy ± chemotherapy) for unresectable EC.

METHODS

This two-arm, open, randomized, multicenter, phase III trial will recruit esophageal squamous cell carcinoma patients (stage IIA-IVB [UICC 2002]; IVB only with metastasis to the supraclavicular or celiac lymph nodes). In all, 164 patients will be randomized using a 1:1 allocation ratio, and stratified by study site and disease stage, especially the extent of lymph node metastasis. Patients in the SIB arm will receive definitive SIB radiotherapy (95% planning target volume/planning gross tumor volume, 50.4 Gy/59.92 Gy/28 f, equivalent dose in 2-Gy fractions = 60.62 Gy). Patients in the SIB + concurrent chemotherapy arm will receive definitive SIB radiotherapy with weekly paclitaxel and a platinum-based drug (5-6 weeks). Four cycles of consolidated chemoradiotherapy will also be recommended. The primary objective is to compare the 1-year, 2-year, and 3-year overall survival of the SIB + chemotherapy group and SIB groups. Secondary objectives include progression-free survival, local recurrence-free rate, completion rate, and adverse events. Detailed radiotherapy protocol and quality-assurance procedures have been incorporated into this trial.

DISCUSSION

In unresectable, locally advanced EC, a safe and effective total radiotherapy dose and reasonable segmentation doses are required for the clinical application of SIB-IMRT + two-drug chemotherapy. Whether this protocol will replace the standard treatment regimen will be prospectively investigated. The effects of SIB-IMRT in patients with poor physical condition who cannot tolerate definitive chemoradiotherapy will also be investigated.

TRIAL REGISTRATION

clinicaltrials.gov ( NCT03308552 , November 1, 2017).

S-1-Based Chemoradiotherapy Followed by Consolidation Chemotherapy With S-1 in Elderly Patients With Esophageal Squamous Cell Carcinoma: A Multicenter Phase II Trial

Introduction: Intensive treatments can often not be administered to elderly patients with esophageal squamous cell carcinoma (ESCC), leading to a poorer prognosis. This multi-center phase II trial aimed to determine the toxicity profile and efficiency of S-1–based simultaneous integrated boost radiotherapy (SIB-RT) followed by consolidation chemotherapy with S-1 in elderly ESCC patients and to evaluate the usefulness of comprehensive geriatric assessment (CGA).

Patients and Methods: We prospectively enrolled 46 elderly patients (age ≥ 70 years) with histopathologically proven ESCC. The patients underwent pretreatment CGA followed by SIB-RT (dose, 59.92 Gy/50.4 Gy) in 28 daily fractions administered using intensity-modulated radiotherapy or volumetric-modulated arc therapy. S-1 was orally administered (40–60 mg/m²) concurrently with radiotherapy and 4–8 weeks later, for up to four 3-week cycles at the same dose.

Results: The median survival time was 22.6 months. The 1- and 2-year overall survival rates were 80.4 and 47.8%, respectively. The overall response rate was 78.3% (36/46). The incidence of grade 3–4 toxicities was 28% (13/46). The most common grade 3–4 toxicities were radiation esophagitis (5/46, 10.9%), nausea (4/46, 8.7%), anorexia (3/46, 6.5%), and radiation pneumonitis (3/46, 6.5%). There were no grade 5 toxicities. CGA identified that 48.8% of patients were at risk for depression and 65.5% had malnutrition.

Conclusion: Concurrent S-1 treatment with SIB-RT followed by 4 cycles of S-1 monotherapy yielded satisfactory tumor response rates and manageable toxicities in selected elderly patients with ESCC. Pretreatment CGA uncovered numerous health problems and allowed the provision of appropriate supportive care.

Clinical Trial Registration:www.ClinicalTrials.gov, identifier: NCT02979691.

Radiation Dose-escalated Chemoradiotherapy Using Simultaneous Integrated Boost Intensity-Modulated Radiotherapy for Locally Advanced Unresectable Thoracic Oesophageal Squamous Cell Carcinoma: A Single-institution Phase I Study

AIMS

About 80% of cases of locally advanced unresectable thoracic oesophageal squamous cell carcinoma recur within the irradiation fields after chemoradiotherapy. Radiation dose escalation using advanced radiotherapy techniques is expected to improve clinical outcomes by reducing local and regional recurrence. The current study aimed to determine the recommended escalated radiation dose for these patients.

MATERIALS AND METHODS

Patients with locally advanced unresectable thoracic oesophageal squamous cell carcinoma with good performance status underwent chemoradiotherapy using simultaneous integrated boost intensity-modulated radiotherapy (SIB-IMRT) with elective nodal irradiation. SIB-IMRT was delivered in five fractions per week. The radiation dose to the unresectable gross tumour was escalated from 66 Gy to a planned maximum dose of 72 Gy in 3 Gy increments in a standard 3 + 3 design. The doses to the resectable component, superficial tumours and elective nodal regions were fixed as 60, 51 and 48 Gy, respectively. Cisplatin and 5-fluorouracil were concurrently administered. Dose-limiting toxicity (DLT) was defined as acute grade 3 oesophagitis, grade 2 pneumonitis, grade 2 cardiac toxicity and a failure to complete planned radiotherapy within 60 days. Locoregional control and overall survival were estimated using the Kaplan-Meier method. Nine patients were enrolled.

RESULTS

DLTs occurred in one of six and two of three patients at doses of 66 and 69 Gy, respectively. All DLTs were grade 3 oesophagitis. The recommended dose was determined as 66 Gy delivered in 30 fractions based on the predefined criteria. With a median follow-up period of 23 months, the 1-year locoregional control and overall survival rates were 67 (95% confidence interval = 19-90) and 78% (95% confidence interval = 36-94), respectively.

CONCLUSION

The recommended radiation dose in chemoradiotherapy using SIB-IMRT with elective nodal irradiation was 66 Gy delivered in 30 fractions.

Sequential boost of intensity-modulated radiotherapy with chemotherapy for inoperable esophageal squamous cell carcinoma: A prospective phase II study

Purpose

This prospective phase II study aimed to determine the efficacy and tolerability of sequential boost of intensity‐modulated radiation therapy (IMRT) with chemotherapy for patients with inoperable esophageal squamous cell carcinoma (ESCC).

Methods

Patients with histologically or cytologically proven inoperable ESCC were enrolled in this study (ChiCTR‐OIC‐17010485). A larger target volume for subclinical lesion was irradiated with 50 Gy, and then, a smaller target volume only including gross tumor was boosted to 66 Gy. The fraction dose was 2 Gy, and no elective node was irradiated. Concurrent and consolidation chemotherapy of fluorouracil (600 mg/m², days 1‐3) plus cisplatin (25 mg/m², days 1‐3) was administered every 4 weeks, for 4 cycles in total. The primary endpoint was 2‐year progression‐free survival (PFS).

Results

Eighty‐eight patients were enrolled in this study. The median age was 65 years (range: 45‐75 years), and 69 patients (78.4%) were men. With the median follow‐up of 26 (range: 3‐95) months, the 2‐ and 5‐year PFS were 39.3% and 36.9%, respectively, and overall survival (OS) were 57.1% and 39.2%, respectively. Tumor stage and concurrent chemotherapy were independent OS predictors. Major acute adverse events were myelosuppression and esophagitis, most of which were grades 1‐2. Nine percent and 2.3% of patients had grade 3 acute esophagitis and late esophageal strictures, respectively.

Conclusions

Sequential boost to 66 Gy by IMRT with chemotherapy was safe and effective for inoperable ESCC. A randomized phase III study to compare with standard dose of 50 Gy is warranted.

Phase I Trial of Intensity-Modulated Hyperfractionated Radiotherapy Boost with Concurrent Chemotherapy Immediately Following Standard Chemoradiotherapy in Patients Primarily with Advanced Intra-thoracic/Cervical Esophageal Squamous Cell Carcinomas

PURPOSE

Local persistence and relapse of disease in the gross tumor volume (GTV) account for the majority of treatment failures after standard chemoradiation therapy. The primary objective of this phase 1 trial was to define the maximum tolerated dose (MTD) of a hyperfractionated radiation therapy (HFRT) boost to the GTV with concurrent weekly paclitaxel and carboplatin after standard-dose chemoradiation therapy, using image guided intensity modulated radiation therapy techniques.

METHODS AND MATERIALS

Eligible patients were given weekly doses of paclitaxel (45 mg/m²) and carboplatin (area under the curve 1.5) for 5 weeks with concurrent radiation therapy (50 Gy), immediately followed by an HFRT boost to the GTV with the same chemotherapy regimen. The boost doses were escalated in increments of 7.2 Gy delivered in 6 twice-daily fractions of 1.2 Gy using a modified Fibonacci design. Once the MTD was established, additional patients were treated at that dose to determine the safety.

RESULTS

Thirty-one patients fulfilled the inclusion criteria. The incidence of dose-limiting toxicity was 0 of 3, 0 of 3, 0 of 3, 1 of 6 (grade 4 esophagitis), 0 of 3, and 2 of 3 (1 case each of grade 5 esophageal fistula and grade 3 pneumotitis) at 7.2, 14.4, 21.6, 28.8, 36, and 43.2 Gy, respectively, indicating an MTD of 36 Gy. Ten patients treated with this MTD showed no dose-limiting toxicities. The most common acute grade 3 or greater toxicities were esophagitis (26%) and neutropenia (19%). Late toxicity of grade 2 esophageal stricture occurred in 4 patients. The overall response rate was 84% (95% confidence interval, 42%-93%) in the entire cohort. The 1-year local control rate was 100% among those receiving a cumulative dose of the MTD or greater.

CONCLUSIONS

The MTD of the HFRT boost after standard chemoradiation therapy in the setting of concurrent chemotherapy was 36 Gy, resulting in the cumulative tumor dose of 86 Gy in patients primarily with advanced intrathoracic/cervical esophageal squamous cell carcinomas and not adenocarcinomas of the gastroesophageal junction. A phase 2 study to further evaluate this regimen is underway.

Effect of modern high-dose versus standard-dose radiation in definitive concurrent chemo-radiotherapy on outcome of esophageal squamous cell cancer: a meta-analysis

Background and objectives

Radiation Therapy Oncology Group (RTOG) 94–05 has demonstrated that higher dose radiation didn’t improve outcome of patients with esophageal cancer (EC). However, several retrospective studies showed that a higher dose radiation based on modern radiotherapy techniques could improve overall survival (OS) and local control rate (LCR) of patients with EC, especially esophageal squamous cell cancer (ESCC). As trials have provided updated and controversial data, we performed this updated meta-analysis to investigate whether high-dose (> = 60 Gy) radiotherapy in definitive concurrent chemo-radiotherapy (CCRT) could yield benefit compared to standard dose radiotherapy.

Methods

A systematic literature search was carried out in the database of MEDLINE, PubMed and Embase. All studies published between 1 January 1990 and 31 December 2018 on the association between radiation dose and curative efficiency in EC were included in this meta-analysis. The hazard ratio (HR) was used to evaluate the time-to-event data employing RevMan version 5.3.

Results

Eight articles with a total of 3736 patients were finally included. Results indicated that there was a significant benefit in favor of high dose radiotherapy (HD-RT) regarding OS (HR = 0.78, 95%CI: 0.72–0.84, p < 0.001; 2-year OS risk ratio (RR) = 1.25, 95%CI: 1.14–1.37, p < 0.001), progression-free survival (PFS) (P = 0.001, HR = 0.7, 95%CI: 0.57–0.87) and LRFS (P < 0.001, HR = 0.52, 95%CI: 0.36–0.74) .

Conclusions

HD-RT (> = 60 Gy) based on modern radiotherapy techniques in definitive CCRT appears to improve OS, PFS amd LRFS compared to the SD-RT in patients with ESCC.

A multicenter phase III study comparing Simultaneous Integrated Boost (SIB) radiotherapy concurrent and consolidated with S-1 versus SIB alone in elderly patients with esophageal and esophagogastric cancer - the 3JECROG P-01 study protocol

BACKGROUND

The importance of definitive radiotherapy for elderly patients with esophageal and esophagogastric-junction cancer is pronounced. However, little is known in terms of the best way to combine radiotherapy with other treatment options. This study aims to compare the efficiency of SIB radiotherapy alone with SIB radiotherapy concurrent and consolidated with S-1 for elderly patients. Comprehensive geriatric assessment is also incorporated in the procedure of treatment.

METHODS/DESIGN

The study is a two arm, open, randomized multicenter Phase III trial with patients over 70 years old with stage IIA-IVB (UICC 2002, IVB only with metastasis to supraclavicular or celiac lymph nodes) squamous cell carcinoma or adenocarcinoma of esophagus or gastroesophageal junction. A total of 300 patients will be randomized using a 1:1 allocation ratio stratified by disease stage and study site. Patients allocated to the SIB arm will receive definitive SIB radiotherapy (95%PTV/PGTV 50.4Gy/59.92Gy/28f) while those randomized to SIB + S-1 arm will receive definitive SIB radiotherapy concurrent and consolidated with S-1. The primary endpoint of the trial is 1-year overall survival. Secondary objectives include progression-free survival, recurrence-free survival (local-regional and distant), disease failure pattern, toxicity profile as well as quality of life. Besides, detailed radiotherapy protocol and quality assurance procedure have been incorporated into this trial.

DISCUSSION

The proportion of elderly patients in esophageal cancer is now growing, but there is a lack of evidence in term of treatment standard for this group of patients, which is what we aim to obtain through this prospective phase III study.

TRIAL REGISTRATION

clinicaltrials.gov NCT02979691 . Registered November 22, 2016.

A phase I/II radiation dose escalation trial using simultaneous integrated boost technique with elective nodal irradiation and concurrent chemotherapy for unresectable esophageal Cancer

Background

To investigate the safety and tolerability of simultaneous integrated boost (SIB) technique concurrent with elective nodal irradiation (ENI) and dual-drug chemotherapy for patients with unresectable esophageal cancer.

Methods

In phase I, the prophylactic PTV received a stable dose of 50.40Gy/1.80Gy/28f while the boost area was planned with 3 consecutive dose levels: the first dose level was 60.76Gy/2.17Gy/28f, and then escalated approximately every 2 Gy. ENI was incorporated in Clinical Target Volume (CTV), and paclitaxel and nedaplatin were given concurrently for at least 5 weeks. In phase II, enrolled patients were treated with Maximum Tolerated Dose (MTD) obtained in phase I and the compliance rate, survival results and toxicities were evaluated.

Results

From December 2014 to April 2017, 53 patients were enrolled. In phase I, 2 out of 6 patients developed Dose-Limiting Toxicity (DLT) at dose level 1. Due to excessive treatment-related toxicities, the escalation process was suspended and de-escalated to 59.92Gy /2.14Gy /28 f. Three patients were treated at this dose level, all of whom completed at least 5 weeks of chemotherapy and none of whom reached a DLT, determining the newly added dose level to be the MTD.

In phase II, 44 patients were treated with MTD, 31 of them (70.0%) completed at least 5 weeks of chemotherapy. The most common Grade 3 or 4 toxicities in phase II included leukopenia (21%) and esophagitis (15%). With a median follow-up time of 16.9 months, 1-y OS, DFS and local failure-free survival were 76.9, 63.6 and 78.8% respectively.

Conclusion

The SIB technique was feasible and safe at the MTD (95% PGTV/PTV 59.92/50.40Gy/28f) concurrent with ENI and dual-drug chemotherapy for patients with unresectable esophageal cancer.

Trial registration

clinicaltrials.govNCT02429622. Retrospectively registered on April 24, 2015.

Electronic supplementary material

The online version of this article (10.1186/s13014-019-1249-5) contains supplementary material, which is available to authorized users.

Is There a Role for an 18F-fluorodeoxyglucose-derived Biological Boost in Squamous Cell Anal Cancer?

AIMS

To investigate the potential role for a biological boost in anal cancer by assessing whether subvolumes of high 18F-fluorodeoxyglucose (FDG) avidity, identified at outset, are spatially consistent during a course of chemoradiotherapy (CRT).

MATERIALS AND METHODS

FDG-positron emission tomography (FDG-PET) scans from 21 patients enrolled into the ART study (NCT02145416) were retrospectively analysed. In total, 29 volumes including both primary tumours and involved nodes >2 cm were identified. FDG-PET scans were carried out before treatment and on day 8 or 9 of CRT. FDG subvolumes were created using a percentage of maximum FDG avidity at thresholds of 34%, 40%, 50%, on the pre-treatment scans, and 70% and 80% on the subsequent scans. Both FDG-PET scans were deformably registered to the planning computed tomography scan. The overlap fraction and the vector distance were calculated to assess spatial consistency. FDG subvolumes for further investigation had an overlap fraction >0.7, as this has been defined in previous publications as a 'good' correlation.

RESULTS

The median overlap fractions between the diagnostic FDG-PET subvolumes 34%, 40% and 50% of maximum standardised uptake value (SUVmax) and subsequent FDG-PET subvolumes of 70% of SUVmax were 0.97, 0.92 and 0.81. The median overlap fraction between the diagnostic FDG-PET subvolumes 34%, 40% and 50% and subsequent FDG-PET subvolumes of 80% were 1.00, 1.00 and 0.92. The median (range) vector distance values between diagnostic FDG-PET subvolumes 34%, 40% and 50% and subsequent FDG-PET subvolumes of 80% were 0.74 mm (0.19-2.94) 0.74 mm (0.19-3.39) and 0.71 mm (0.2-3.29), respectively. Twenty of 29 volumes (69.0%) achieved a threshold > 0.7 between the FDG 50% subvolume on the diagnostic scan and the FDG 80% subvolume on the subsequent scan.

CONCLUSION

FDG-avid subvolumes identified at baseline were spatially consistent during a course of CRT treatment. The subvolume of 50% of SUVmax on the pre-treatment scan could be considered as a potential target for dose escalation.

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.

Partially ablative radiotherapy (PAR) for large mass tumors using simultaneous integrated boost: A dose-escalation feasibility study

Purpose

This study aimed to assess the feasibility to plan and deliver highly heterogeneous doses to symptomatic large tumors using volumetric modulated arc therapy (VMAT) and simultaneous integrated boost (SIB) during a short course palliative accelerated radiotherapy.

Methods

A patient with a large symptomatic chordoma infiltrating the right gluteal region was selected. A modified SIB treatment was implemented to irradiate the central volume of the tumor (boost target volume, BTV) up to 10 Gy/fraction in a dose escalation trial while maintaining the remaining tumor volume (planning target volume, PTV) and the surrounding healthy tissues within 5 Gy/fraction in twice daily fractions for two consecutive days. Four SIB plans were generated in the dual‐arc modality; a basal dose of 20 Gy was prescribed to the PTV, while the BTV was boosted up to 40 Gy. For comparison purposes, plans obtained with a sequential boost (SEQ plans) were also generated. All plans were optimized to deliver at least 95% of the prescription dose to the targets. Dose contrast index (DCI), conformity index (CI), integral dose (ID), and the irradiated body volumes at 5, 10, and 20 Gy were evaluated.

Results

At equal targets coverage, SIB plans provided major improvement in DCI, CI, and ID with respect to SEQ plans. When BTV dose escalated up to 200% of PTV prescription, DCI resulted in 66% for SIB plans and 37% for SEQ plans; the ID increase was only 11% for SIB plans (vs 27% for SEQ plans) and the increase in healthy tissues receiving more than 5, 10, and 20 Gy was less than 2%. Pretreatment dose verification reported a γ‐value passing rate greater than 95% with 3%(global)‐2 mm.

Conclusion

A modified SIB technique is dosimetrically feasible for large tumors, where doses higher than the tolerance dose of healthy tissues are necessary to increase the therapeutic gain.

18F-fluorodeoxyglucose positron emission tomography predicts lymph node responses to definitive chemoradiotherapy in esophageal squamous cell carcinoma patients

Purpose

To evaluate the capability of ¹⁸F-fluorodeoxyglucose positron emission tomography/ computed tomography (¹⁸F-FDG-PET/CT) to predict the clinical response of metastatic lymph node (mLN) to definitive chemoradiotherapy (dCRT) and guide personalized radiation dose in esophageal squamous cell carcinoma (ESCC) patients.

Patients and methods

One hundred and forty-three mLNs from 59 patients with ESCC treated with dCRT and who had undergone a pretreatment ¹⁸F-FDG-PET/CT scan were included in the study. All defined mLNs were contoured by nuclear medicine radiologists. Response was evaluated by contrast-enhanced computed tomography and ¹⁸F-FDG-PET/CT.

Results

Sixty-nine mLNs showed complete response (CR), and 74 mLNs showed non-complete response. The 143 mLNs were divided into 4 groups (Groups 1–4) based on the quartiles of maximum standardized uptake value (SUVmax-G1, SUVmax-G2, SUVmax-G3, and SUVmax-G4) and metabolic tumor volume (MTV-G1, MTV-G2, MTV-G3, and MTV-G4). The CR rate of SUVmax-G2 was significantly higher than the other 3 groups. The escalated radiation dose improved the CR rate of lymph nodes in SUVmax-G3 (55 Gy) and SUVmax-G4 (61 Gy). The lowest CR rate was found in MTV-G4 (the group with the largest MTV). The escalated radiation dose (59.7 Gy) improved the CR rate of lymph node in MTV-Groups 3 and 4.

Conclusion

Pretreatment metabolic parameters can predict the response of mLNs to dCRT for patients with ESCC. The parameters could also be used to guide personalized dose to mLNs.

The Role of PET-Based Radiomic Features in Predicting Local Control of Esophageal Cancer Treated with Concurrent Chemoradiotherapy

This study was designed to evaluate the predictive performance of ¹⁸F-fluorodeoxyglucose positron emission tomography (PET)-based radiomic features for local control of esophageal cancer treated with concurrent chemoradiotherapy (CRT). For each of the 30 patients enrolled, 440 radiomic features were extracted from both pre-CRT and mid-CRT PET images. The top 25 features with the highest areas under the receiver operating characteristic curve for identifying local control status were selected as discriminative features. Four machine-learning methods, random forest (RF), support vector machine, logistic regression, and extreme learning machine, were used to build predictive models with clinical features, radiomic features or a combination of both. An RF model incorporating both clinical and radiomic features achieved the best predictive performance, with an accuracy of 93.3%, a specificity of 95.7%, and a sensitivity of 85.7%. Based on risk scores of local failure predicted by this model, the 2-year local control rate and PFS rate were 100.0% (95% CI 100.0–100.0%) and 52.2% (31.8–72.6%) in the low-risk group and 14.3% (0.0–40.2%) and 0.0% (0.0–40.2%) in the high-risk group, respectively. This model may have the potential to stratify patients with different risks of local failure after CRT for esophageal cancer, which may facilitate the delivery of personalized treatment.

PET imaging in adaptive radiotherapy of gastrointestinal tumors

INTRODUCTION

Radiotherapy is a cornerstone in the multimodality treatment of several gastrointestinal (GI) tumors. Positron-emission tomography (PET) has an established role in the diagnosis, response assessment and (re-)staging of these tumors. Nevertheless, the value of PET in adaptive radiotherapy remains unclear. This review focuses on the role of PET in adaptive radiotherapy, i.e. during the treatment course and in the delineation process.

EVIDENCE ACQUISITION

The MEDLINE database was searched for the terms ("Radiotherapy"[Mesh] AND "Positron-Emission Tomography"[Mesh] AND one of the site-specific keywords, yielding a total of 1710 articles. After abstract selection, 27 papers were identified for esophageal neoplasms, 1 for gastric neoplasms, 9 for pancreatic neoplasms, 6 for liver neoplasms, 1 for biliary tract neoplasms, none for colonic neoplasms, 15 for rectal neoplasms and 12 for anus neoplasms.

EVIDENCE SYNTHESIS

The use of PET for truly adaptive radiotherapy during treatment for GI tumors has barely been investigated, in contrast to the potential of the PET-defined metabolic tumor volume for optimization of the target volume. The optimized target definition seems useful for treatment individualization such as focal boosting strategies in esophageal, pancreatic and anorectal cancer. Nevertheless, for all GI tumors, further investigation is needed.

CONCLUSIONS

In general, too little data are available to conclude on the role of PET imaging during radiotherapy for ART strategies in GI cancer. On the other hand, based on the available evidence, the use of biological imaging for target volume adaptation seems promising and could pave the road towards individualized treatment strategies.

Advances in radiotherapy for esophageal cancer

Esophageal cancer is a common type of malignancy worldwide and usually requires multidisciplinary care. Radiotherapy plays an important part in management of the disease. During the past few years, researchers have made much progress about radiotherapy for esophageal cancer, which was revealed in every aspect of clinical practice. Neoadjuvant chemoradiotherapy remains the standard treatment for locally advanced esophageal cancer, whereas neoadjuvant chemotherapy appears to show less toxicities and non-inferior prognosis. What's more, definitive chemoradiotherapy could be an option for non-surgical candidates and good responders to chemoradiotherapy. Advances in radiation techniques result in higher conformity, homogeneity, more normal tissue sparing and less treatment time. Promising prognoses and less toxicities were also seen in advanced techniques. As radiation dose higher than 50 Gy obtains better local control and survival, simultaneously integrated boost is designed to increase primary tumor dosage and keep prophylactic dose to subclinical areas. Elective nodal irradiation brings about better local control but do not show advantages in survival compared with involved field irradiation (IFI). As a trend, more tolerable chemoradiotherapy regimen would be taken into account in dealing with elderly patients.

Radiotherapy for esophageal carcinoma: dose, response and survival

Esophageal cancer (EC) is an extremely aggressive, lethal malignancy that is increasing in incidence worldwide. At present, definitive chemoradiotherapy is accepted as the standard treatment for locally advanced EC. The EC guidelines recommend a radiation dose of 50.4 Gy for definitive treatment, yet the outcomes for patients who have received standard-dose radiotherapy remain unsatisfactory. However, some studies indicate that a higher radiation dose could improve local tumor control, and may also confer survival benefits. Some studies, however, suggest that high-dose radiotherapy does not bring survival benefit. The available data show that most failures occurred in the gross target volume (especially in the primary tumor) after definitive chemoradiation. Based on those studies, we hypothesize that at least for some patients, more intense local therapy may lead to better local control and survival. The aim of this review is to evaluate the radiation dose, fractionation strategies, and predictive factors of response to therapy in functional imaging for definitive chemoradiotherapy in esophageal carcinoma, with an emphasis on seeking the predictive model of response to CRT and trying to individualize the radiation dose for EC patients.

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.

Potential of Proton Therapy to Reduce Acute Hematologic Toxicity in Concurrent Chemoradiation Therapy for Esophageal Cancer

PURPOSE

Radiation therapy dose escalation using a simultaneous integrated boost (SIB) is predicted to improve local tumor control in esophageal cancer; however, any increase in acute hematologic toxicity (HT) could limit the predicted improvement in patient outcomes. Proton therapy has been shown to significantly reduce HT in lung cancer patients receiving concurrent chemotherapy. Therefore, we investigated the potential of bone marrow sparing with protons for esophageal tumors.

METHODS AND MATERIALS

Twenty-one patients with mid-esophageal cancer who had undergone conformal radiation therapy (3D50) were selected. Two surrogates for bone marrow were created by outlining the thoracic bones (bone) and only the body of the thoracic vertebrae (TV) in Eclipse. The percentage of overlap of the TV with the planning treatment volume was recorded for each patient. Additional plans were created retrospectively, including a volumetric modulated arc therapy (VMAT) plan with the same dose as for 3D50; a VMAT SIB plan with a dose prescription of 62.5 Gy to the high-risk subregion within the planning treatment volume; a reoptimized TV-sparing VMAT plan; and a proton therapy plan with the same SIB dose prescription. The bone and TV dose metrics were recorded and compared across all plans and variations with respect to PTV and percentage of overlap for each patient.

RESULTS

The 3D50 plans showed the highest bone mean dose and TV percentage of volume receiving ≥30 Gy (V30Gy) for each patient. The VMAT plans irradiated a larger bone V10Gy than did the 3D50 plans. The reoptimized VMAT62.5 VT plans showed improved sparing of the TV volume, but only the proton plans showed significant sparing for bone V10Gy and bone mean dose, especially for patients with a larger PTV.

CONCLUSIONS

The results of the present study have shown that proton therapy can reduced bone marrow toxicity.

Patterns of failure and clinical outcomes of definitive radiotherapy for cervical esophageal cancer

Purpose

Because of the scarcity of cervical esophageal cancer (CEC), data for this disease entity is limited. We aim to evaluate the outcomes, prognostic factors and failure patterns of CEC treated by contemporary radiotherapy (RT).

Methods

We retrospectively analyzed 86 CEC patients consecutively treated between 2007 and 2015 by definitive RT with or without concurrent chemotherapy. RT was mainly delivered with Intensity Modulated Irradiation Therapy (IMRT) or Volumetric-Modulated Arc Therapy (VMAT). Statistical analyses were performed on survival, prognostic factors and failure patterns.

Results

The median follow-up time was 19.4 months. The 3-year overall survival (OS), local regional failure free survival (LRFFS), distant metastatic free survival (DMFS), and progression free survival (PFS) were 53.6%, 57.9%, 81.5% and 41.5%, respectively. Independent predictors for poorer OS were N stage, hoarseness and recurrent laryngeal nerve lymph node (RLN) involvement, and predictors for LRFFS were N stage and EQD2 (equivalent dose in 2 Gy fraction) to gross tumor volume (GTV), with ≥ 66Gy achieving local control of 94.7%. Patients receiving elective nodal irradiation (ENI) had better nodal regional control than those receiving involved field irradiation (IFI). 31 (36%) patients had treatment failure and 15 (17.4%), 8 (9.3%) and 14 (16.2%) patients had local, regional, and distant failure, respectively. 86.7% (13/15) local failures were within GTV, and supraclavicular region (62.5%, 5/8) was the most common regional failure site. No severe toxicities were observed.

Conclusions

Our results seem to indicate that good locoregional control might be achieved for CEC with adequate radiation dose and treatment planning approaches.

Definitive chemoradiotherapy

Definitive chemoradiotherapy (dCRT) is reflecting a treatment standard in oesophageal cancer. For irresectable localised tumours and for inoperable patients, dCRT can change the treatment intent from palliative to curative. In patients with squamous cell carcinoma (SCC), in particular in those of cervical location, dCRT is a proper alternative for treatment that may include radical surgery. Patients with localised locoregional recurrence after primary surgery can survive for long-term after salvage CRT.

Dose painting by means of Monte Carlo treatment planning at the voxel level

PURPOSE

To develop a new optimization algorithm to carry out true dose painting by numbers (DPBN) planning based on full Monte Carlo (MC) calculation.

METHODS

Four configurations with different clustering of the voxel values from PET data were proposed. An optimization method at the voxel level under Lineal Programming (LP) formulation was used for an inverse planning and implemented in CARMEN, an in-house Monte Carlo treatment planning system.

RESULTS

Beamlet solutions fulfilled the objectives and did not show significant differences between the different configurations. More differences were observed between the segment solutions. The plan for the dose prescription map without clustering was the better solution.

CONCLUSIONS

LP optimization at voxel level without dose-volume restrictions can carry out true DPBN planning with the MC accuracy.

Different definitions of esophagus influence esophageal toxicity prediction for esophageal cancer patients administered simultaneous integrated boost versus standard-dose radiation therapy

We aim to evaluate whether different definitions of esophagus (DEs) impact on the esophageal toxicity prediction for esophageal cancer (EC) patients administered intensity-modulated radiation therapy with simultaneous integrated boost (SIB-IMRT) vs. standard-dose IMRT (SD-IMRT). The esophagus for 21 patients diagnosed with primary EC were defined in the following four ways: the whole esophagus, including the tumor (ESO_whole); ESO_whole within the treatment field (ESO_infield); ESO_infield, excluding the tumor (ESO_{infield-tumor}) and ESO_whole, excluding the tumor (ESO_whole-tumor). The difference in the dose variation, acute esophageal toxicity (AET) and late esophageal toxicity (LET) of four DEs were compared. We found that the mean esophageal dose for ESO_whole, ESO_infield, ESO_{infield-tumor} and ESO_whole-tumor were increased by 7.2 Gy, 10.9 Gy, 4.6 Gy and 2.0 Gy, respectively, in the SIB-IMRT plans. Radiobiological models indicated that a grade ≥ 2 AET was 2.9%, 3.1%, 2.2% and 1.6% higher on average with the Kwint model and 14.6%, 13.2%, 7.2% and 3.4% higher with the Wijsman model for the four DEs. A grade ≥ 3 AET increased by 4.3%, 7.2%, 4.2% and 1.2%, respectively. Additionally, the predicted LET increased by 0.15%, 0.39%, 1.2 × 10⁻²% and 1.5 × 10⁻³%. Our study demonstrates that different DEs influence the esophageal toxicity prediction for EC patients administered SIB-IMRT vs. SD-IMRT treatment.

Radiobiological evaluation of simultaneously dose-escalated versus non-escalated intensity-modulated radiation therapy for patients with upper thoracic esophageal cancer

OBJECTIVE

To compare the radiobiological response between simultaneously dose-escalated and non-escalated intensity-modulated radiation therapy (DE-IMRT and NE-IMRT) for patients with upper thoracic esophageal cancer (UTEC) using radiobiological evaluation.

METHODS

Computed tomography simulation data sets for 25 patients pathologically diagnosed with primary UTEC were used in this study. DE-IMRT plan with an escalated dose of 64.8 Gy/28 fractions to the gross tumor volume (GTV) and involved lymph nodes from 25 patients pathologically diagnosed with primary UTEC, was compared to an NE-IMRT plan of 50.4 Gy/28 fractions. Dose-volume metrics, tumor control probability (TCP), and normal tissue complication probability for the lung and spinal cord were compared. In addition, the risk of acute esophageal toxicity (AET) and late esophageal toxicity (LET) were also analyzed.

RESULTS

Compared with NE-IMRT plan, we found the DE-IMRT plan resulted in a 14.6 Gy dose escalation to the GTV. The tumor control was predicted to increase by 31.8%, 39.1%, and 40.9% for three independent TCP models. The predicted incidence of radiation pneumonitis was similar (3.9% versus 3.6%), and the estimated risk of radiation-induced spinal cord injury was extremely low (<0.13%) in both groups. Regarding the esophageal toxicities, the estimated grade ≥2 and grade ≥3 AET predicted by the Kwint model were increased by 2.5% and 3.8%. Grade ≥2 AET predicted using the Wijsman model was increased by 14.9%. The predicted incidence of LET was low (<0.51%) in both groups.

CONCLUSION

Radiobiological evaluation reveals that the DE-IMRT dosing strategy is feasible for patients with UTEC, with significant gains in tumor control and minor or clinically acceptable increases in radiation-induced toxicities.

Local Control and Toxicity of a Simultaneous Integrated Boost for Dose Escalation in Locally Advanced Esophageal Cancer: Interim Results from a Prospective Phase I/II Trial

INTRODUCTION

Approximately 50% of recurrences after standard-dose chemoradiation for locally advanced esophageal cancer occur within the gross tumor volume (GTV). In this prospective phase I/II clinical trial, we explored the use of a simultaneous integrated boost (SIB) dose to the GTV.

METHODS

Forty-four patients with unresectable esophageal cancer received chemoradiation with an SIB of 58.8 to 63 Gy to the GTV and 50.4 Gy to the planning target volume, all in 28 fractions, with 5 weeks of concurrent docetaxel and fluorouracil or capecitabine. The end points were maximum tolerated dose, time to local failure, and clinical response.

RESULTS

Excluding those with less than 6 months of follow-up, 38 patients were evaluated at the time of analysis. The median age was 65 years (range 37-84). Most patients (71%) were men; 84% had T3 disease, 37% had N1 disease, 26% had N2 disease, 13% had M1 disease, and 50% had adenocarcinoma. The maximum tolerated SIB dose was 63 Gy. None experienced Common Terminology Criteria for Adverse Events grade 4 or 5 toxicity. At a median follow-up time of 13.3 months (range 1.2-36.2), 11 (29%) had local failure (median time to local failure 2.5 months [range 1.5-23.9]). A comparison with 97 similar patients who received 50.4 Gy without an SIB showed that the SIB reduced the local failure rate for patients with node-positive disease (13% versus 56%, p = 0.04), adenocarcinoma (26% versus 59%, p = 0.02), or stage III-IV disease (29% versus 55%, p = 0.04).

CONCLUSIONS

SIB intensity-modulated radiation therapy to gross primary disease may improve local control for patients with unresectable locally advanced esophageal cancer, especially those with adenocarcinoma.

Impact of PET/CT on radiation treatment in patients with esophageal cancer: A systematic review

PURPOSE

With the advances in radiotracers, positron emission tomography/computed tomography (PET/CT) is recognized as a useful adjunct to anatomic imaging with CT, MRI and endoscopic ultrasonography (EUS). The objective of this review was to comprehensively analyze the roles of PET/CT for the radiotherapy of esophageal cancer.

METHODS

In this review, we focused on issues concerning the application of PET/CT in TNM staging, target volume delineation and response to therapy, both for the primary tumor and regional lymph nodes. Furthermore, the following questions were addressed: how does PET/CT guide appropriate treatment protocols, how does it allow accurate tumor delineation and how does it guide prognosis and future treatment decisions.

RESULTS AND CONCLUSION

For the staging of esophageal cancer, PET/CT played a crucial role in exploring distant malignant lymph nodes and metastasis with high sensitivity, specificity and accuracy. PET/CT using different radiotracer provided a serial of thresholding methods based on standardized uptake value (SUV) to assist in auto-contouring the gross tumor volume (GTV). The change in SUV may offer a potential paradigm of personalized treatment to definitive chemoradiotherapy (CRT). In total, PET/CT has sought to further optimize radiotherapy treatment planning for patients with esophageal cancer.