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

Cardiac CT reveals high prevalence of coronary artery disease in esophageal cancer eligible for radiotherapy

BACKGROUND

Assessment of cardiac disease before cancer therapy is crucial, as advancements in cancer treatment have led to prolonged survival and an increase in cardiovascular complications. Specifically, esophageal cancer and heart disease share common risk factors, such as smoking and obesity. Radiation therapy (RT) for esophageal cancer is associated with elevated cardiac radiation exposure. This study aimed to assess the prevalence of coronary artery disease (CAD) in patients with esophageal cancer who were eligible for RT.

METHODS

We examined the prevalence of coronary artery stenosis, abnormal myocardial perfusion, and late enhancement using pre-RT cardiac computed tomography (CT) data of 41 patients with thoracic esophageal cancer who were referred for RT between January 2017 and June 2023 and had no history of ischemic heart disease.

RESULTS

The median age of the 41 patients was 71 years, with 40 patients being male. Cardiac CT identified significant coronary stenosis (≥50% luminal narrowing) in 18 patients (44%), among whom 9 (50%) had severe stenosis, multivessel disease, or myocardial ischemia. Significant stenosis was most frequently observed in the left anterior descending artery (16/18). Late enhancement, indicating myocardial infarction, was observed in seven patients (17%).

INTERPRETATION

Patients with esophageal cancer without a history of ischemic heart disease had a high prevalence (44%) of CAD, with half of them having severe stenosis, multivessel disease, or myocardial ischemia. Given the high prevalence of coronary stenosis, pre-treatment cardiac evaluation is crucial for patients with esophageal cancer. Incorporating cardiac CT findings into radiotherapy planning is recommended to optimize patient care.

Treatment strategies for elderly patients with locally advanced esophageal cancer: a systematic review and meta-analysis

BACKGROUND

Neoadjuvant chemoradiotherapy (nCRT) followed by surgery remains a standard of care for resectable esophageal cancer (EC), and definitive chemoradiotherapy (dCRT) is an alternative for unresectable diseases. However, it is controversial for the use of the two aggressive regimens in elderly patients.

METHODS

We systematically searched multiple databases for studies comparing overall survival (OS) and/or progression-free survival (PFS) between dCRT and surgery (nCRT + surgery or surgery alone) or between dCRT and radiotherapy (RT) alone in elderly patients (age ≥ 65 years) until March 28, 2024. Statistical analysis was performed using random-effects model.

RESULTS

Fourty-five studies with 33,729 patients were included. dCRT significantly prolonged OS (hazard ratio [HR] = 0.64, 95% confidence interval [CI]: 0.58-0.70) and PFS (HR = 0.67, 95% CI: 0.60-0.76) compared to RT alone for unresectable EC, and resulted in a worse OS compared to surgery for resectable cases (HR = 1.34, 95% CI: 1.23-1.45). Similar results of OS were also observed when the multivariate-adjusted HRs were used as the measure of effect (dCRT vs. RT alone: HR = 0.65, 95% CI: 0.58-0.73; dCRT vs. surgery: HR = 1.49, 95% CI: 1.28-1.74). Subgroup analyses according to age group (≥ 70, ≥ 75, or ≥ 80 years), study design, study region, histological type, radiation field, chemotherapy regimen revealed comparable results.

CONCLUSIONS

nCRT + surgery is likely a preferred strategy for elderly patients with good physiological conditions; and dCRT is a better alternative for unresectable cases. Advanced age alone does not appear to be a key predictor for the tolerability of the two aggressive treatments.

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.

Clinical impact of radiation-induced myocardial damage detected by cardiac magnetic resonance imaging and dose-volume histogram parameters of the left ventricle as prognostic factors of cardiac events after chemoradiotherapy for esophageal cancer

This prospective study aimed to evaluate whether radiation (RT)-induced myocardial damage by cardiac magnetic resonance (CMR) imaging could be a predictor of cardiac events after chemoradiotherapy (CRT) for esophageal cancer and determine the dose-volume histogram (DVH) parameters of the left ventricle (LV) in predicting cardiac events. CMR imaging was performed before and 6 months after CRT in patients receiving definitive CRT. RT-induced myocardial damage was defined as abnormal CMR findings indicating myocardial fibrosis corresponding to an isodose line of ≥30 Gy. The cutoff values of the LV DVH parameters were calculated using the receiver operating characteristic curve based on the presence of RT-induced myocardial damage. The prognostic factors related to cardiac events of Grade 3 or higher were examined. Twenty-three patients were enrolled in the study. RT-induced myocardial damage by late gadolinium enhancement and/or an increase of 100 ms or higher in native T1 post-CRT was detected in 10 of the 23 patients. LV V45 was the best predictive factor for RT-induced myocardial damage with a cutoff value of 2.1% and an area under the curve of 0.75. The median follow-up period was 82.1 months. The 5- and 7-year cumulative incidences of cardiac events of Grade 3 or higher were 14.7 and 22.4%, respectively. RT-induced myocardial damage and LV V45 were significant risk factors (P = 0.015 and P = 0.013, respectively). RT-induced myocardial damage is a significant predictor of cardiac events. LV V45 is associated with RT-induced myocardial damage and subsequent cardiac events.

Long-term results of chemoradiotherapy with elective nodal irradiation for resectable locally advanced esophageal cancer in three-dimensional planning system

BACKGROUND

We evaluated the long-term results of definitive chemoradiotherapy (CRT) with elective nodal irradiation (ENI) using a three-dimensional (3D) planning system for resectable, locally advanced esophageal squamous cell carcinoma (LA-ESCC).

METHODS

This retrospective study included 65 patients with LA-ESCC who started CRT between 2006 and 2017. Patients with Stage I-IV LA-ESCC according to the Union for International Cancer Control TNM classification (eighth edition) were included. In stage IV, only supraclavicular lymph node (LN) metastasis was included. All patients received radiotherapy with ENI and concurrent chemotherapy with platinum and 5-fluorouracil.

RESULTS

The median age of the patients was 70 years (range 52-83 years). Stage I, II, III, and IV diseases were observed in 3 (5%), 28 (43%), 22 (34%), and 12 patients (18%), respectively. The median prescription dose was 66 Gy (range 50.4-66 Gy). The median follow-up period for the survivors was 71 months (range 8-175 months). The 5-year overall survival (OS) and progression-free survival rates were 54 and 43%, respectively. The 5-year OS rates for stages I-II and III-IV were 67 and 42%, respectively. Recurrence occurred in 29 patients (45%), and recurrence of regional LNs only occurred in 2 patients (3%). Grade 3 or higher late adverse events were observed in 8 patients (12%). Grade 5 heart failure occurred in two patients (3%); both had cardiovascular disease before treatment.

CONCLUSION

The long-term results of definitive CRT with ENI for resectable LA-ESCC were favorable. ENI with a 3D planning system may reduce regional LN recurrence and late adverse events.

Construction of survival prediction model for elderly esophageal cancer

Background

The purpose of this study was to analyze the clinical characteristics and prognosis of EPEC and to construct a prediction model based on the SEER database.

Methods

All EPECs from the SEER database were retrospectively analyzed. A comprehensive and practical nomogram that predicts the overall survival (OS) of EPEC was constructed. Univariate and multivariate Cox regression analysis was performed to explore the clinical factors influencing the prognosis of EPEC, and finally, the 1 -, 3 - and 5-year OS were predicted by establishing the nomogram. The discriminant and predictive ability of the nomogram was evaluated by consistency index (C-index), calibration plot, area under the curve (AUC), and receiver operating characteristic (ROC) curve. Decision curve analysis (DCA) was used to evaluate the clinical value of the nomogram.

Results

A total of 3478 patients diagnosed with EPEC were extracted from the SEER database, and the data were randomly divided into the training group (n=2436) and the validation group (n=1402). T stage, N stage, M stage, surgery, chemotherapy, radiotherapy, age, grade, and tumor size were independent risk factors for 1 -, 3 - and 5-year OS of EPEC (P< 0.05), and these factors were used to construct the nomogram prediction mode. The C-index of the validation and training cohorts was 0.718 and 0.739, respectively, which were higher than those of the TNM stage system. The AUC values of the nomogram used to predict 1-, 2-, and 3-year OS were 0.751, 0.744, and 0.786 in the validation cohorts (0.761, 0.777, 0.787 in the training cohorts), respectively. The calibration curve of 1-, 2-, and 3-year OS showed that the prediction of the nomogram was in good agreement with the actual observation. The nomogram exhibited higher clinical utility after evaluation with the 1-, 2-, and 3-year DCA compared with the AJCC stage system.

Conclusions

This study shows that the nomogram prediction model for EPEC based on the SEER database has high accuracy and its prediction performance is significantly better than the TNM staging system, which can accurately and individually predict the OS of patients and help clinicians to formulate more accurate and personalized treatment plans.

Comparison of involved-field intensity-modulated radiotherapy combined with S-1 vs radiotherapy alone for elderly patients with esophageal cancer

BACKGROUND

It is estimated that about 30% of esophageal cancer (EC) patients are over 70 years old. Therefore, there is less evidence on the diagnosis and management of elderly EC patients. It is important to explore how elderly EC patients benefit from radical radiochemotherapy regimens, including the target area of radiotherapy (RT), radiation dose and fraction, and choice of chemotherapy drugs.

AIM

To compare the efficacy of involved-field intensity-modulated RT (IF-IMRT) combined with S-1 vs RT alone in the treatment of elderly EC patients in terms of safety, short-term response, and survival.

METHODS

Thirty-four EC patients aged > 70 years were prospectively enrolled between December 2017 and December 2019. Based on the random number table, they were divided into an IF-IMRT + S-1 group and an IF-IMRT alone group, with 17 patients in each group. All patients were treated with IF-IMRT at a dose of 50.4-56 Gy in 28-30 fractions (1.8-2 Gy/fraction, 5 fractions/wk). Oral S-1 was administered concomitantly in the IF-IMRT + S-1 group for 14 consecutive days, and a second cycle was started 7 d after drug withdrawal. After RT, 4 cycles of S-1 treatment were offered as the consolidation chemotherapy. The safety, short-term response, and survival were observed after the treatment.

RESULTS

As of April 2022, these 34 patients had been followed up for 15.2-32.5 mo, with a median follow-up period of 24.5 mo. Complete efficacy indicators were obtained from all the patients. The objective response rate was 88.2% vs 76.5%, respectively, in the IF-IMRT + S-1 group and the RT alone group, where as the disease control rate was 100% vs 82.4%, respectively. The incidence of adverse events including grade 1-2 fatigue, granulocytopenia, thrombocytopenia, anemia, radiation esophagitis, radiation-induced skin injury, and radiation-induced lung injury was not significantly different between these two groups, so was the incidence of the grade 3 radiation esophagitis (0% vs 5.7%). The rate of progressive disease (PD) was 52.9% (n = 9) in the IF-IMRT + S-1 group and 64.7% (n = 11) in the RT alone group. The median progression-free survival (PFS) was 23.4 mo vs 16.3 mo, and the 2-year PFS rate was 42% vs 41.2%. The median overall survival (OS) was 27.0 mo vs 23.0 mo, and the 2-year OS rate was 58.8% vs 47.1%. Multivariate analysis showed that age was a significant prognostic factor (P = 0.0019); patients aged < 75 years had a significant survival advantage over patients aged ≥ 75 years. The locations of EC also affected the prognosis. In the IF-IMRT + S-1 group, the number of chemotherapy cycles was a significant prognostic factor (P = 0.0125), and the risk of PD was significantly lower in EC patients who had received 6 cycles of chemotherapy than those who had received 2-5 cycles of chemotherapy.

CONCLUSION

Compared with IF-IMRT alone, IF-IMRT + S-1 shows the benefits of preventing PD and prolonging survival without increasing adverse reactions. Therefore, this concurrent radiochemotherapy deserves clinical application.

Association Between Radiotherapy and Death From Cardiovascular Disease Among Patients With Cancer: A Large Population-Based Cohort Study

Background This study aimed to investigate the association between radiotherapy for cancer and cardiovascular disease (CVD) deaths and evaluate the relative risk for CVD deaths in the general population and among patients with cancer treated with radiotherapy. Methods and Results The statistics of cancers from 16 sites were extracted from the Surveillance, Epidemiology, and End Results database and evaluated. Multivariable Cox proportional hazards regression analysis was used to analyze the association between radiotherapy and cardiovascular-specific survival. The standardized mortality ratio for CVD deaths was estimated by comparing the observed deaths of patients with cancer treated with radiotherapy to the expected deaths of the general population. Of the 2 214 944 patients identified from the database, 292 102 (13.19%) died from CVD. Multivariable Cox proportional hazards regression analyses demonstrated that radiotherapy was an independent risk factor for cardiovascular-specific survival among patients with lung and bronchus, cervix uteri, corpus uteri, and urinary bladder cancers. The long-term cardiovascular-specific survival of patients with cancer who underwent radiotherapy was significantly lower than that of patients who did not undergo radiotherapy. The incidence of CVD deaths among patients with lung and bronchus, cervix uteri, corpus uteri, and urinary bladder cancers who underwent radiotherapy was higher than that among the general population. Standardized mortality ratio significantly decreased with increasing age at cancer diagnosis, gradually decreased within 10 years of diagnosis and increased after 10 years of diagnosis. Conclusions Radiotherapy is associated with worse cardiovascular-specific survival in patients with lung and bronchus, cervix uteri, corpus uteri, and urinary bladder cancers. Long-term surveillance of cardiovascular conditions should be performed after radiotherapy.

A Prospective Phase II Study of Simultaneous Modulated Accelerated Radiotherapy Concurrently With CDDP/S1 for Esophageal Squamous Cell Carcinoma in the Elderly

Background

To explore the efficacy and toxicity of simultaneous modulated accelerated radiotherapy (SMART) concurrently with cisplatin (CDDP) and S1 (tegafur/gimeracil/oteracil) in elderly patients with esophageal squamous cell carcinoma (ESCC).

Methods

This single-arm, phase II study enrolled pathologically confirmed, stage II-IVa ESCC of 70-80 years old and Eastern Cooperative Oncology Group performance status (ECOG PS) 0-2. Patients received SMART (64 Gy to gross tumor volume and 48 Gy to clinical target volume in 30 fractions) with concurrent CDDP (day 1 of each week) and S1 (days 1-14, 22-35). The primary endpoint was objective response rate (ORR). The secondary endpoints included progression-free survival (PFS), overall survival (OS) and toxicities.

Results

Thirty-seven eligible patients were analyzed with median follow-up of 25.7 months for all and 46.1 months for survivors. The ORR was 88.9%. Patients with baseline weight loss <5% (p=0.050) and nutritional risk index (NRI) ≥105.2 (p=0.023) had better tumor response. Median PFS was 13.8 months with 2-year PFS of 37.5%. Median OS was 27.7 months with 2-year OS of 57.5%. OS was significantly associated with ECOG PS (p=0.005), stage (p=0.014), gross tumor volume (p=0.004), baseline NRI (p=0.036), baseline C-reactive protein (CRP) level (p=0.003) and tumor response (p=0.000). CRP level (p=0.016) and tumor response (p=0.021) were independently prognostic of OS. ≥grade 3 anemia, neutropenia and thrombocytopenia occurred in 2.7%, 10.8% and 13.5% of patients; ≥grade 3 esophagitis and pneumonitis occurred in 18.9% and 2.7% of patient, respectively.

Conclusion

SMART concurrently with CDDP/S1 yielded satisfactory response rate, survival outcome and tolerable treatment-related toxicities in elderly patients with ESCC. Further studies are warranted to validate the results.

Rural-Urban Differences in Esophagectomy for Cancer

Introduction

Patients who are disadvantaged socioeconomically or live in rural areas may not pursue surgery at high-volume centers where outcomes are better for some complex procedures. The objective of this study was to compare rural and urban patient differences directly by location of residence and outcomes after undergoing esophagectomy for cancer.

Methods

An analysis of the Healthcare Cost and Utilization Project National Inpatient Sample (HCUP-NIS) database was performed, capturing adult patients with esophageal cancer who underwent esophagectomy. Patients were stratified into rural or urban groups by the National Center for Health Statistics Urban-Rural Classification Scheme. Demographics, hospital variables, and outcomes were compared.

Results

A total of 2,877 patients undergoing esophagectomy for esophageal cancer were captured by the database, with 228 (7.92%) rural and 2,575 (89.50%) urban patients. The rural and urban groups had no differences in age, race, and insurance status, and shared many common comorbidities. Major outcomes of mortality (3.95% versus 4.27%, p = 0.815) and length of stay (15.75 ± 13.22 vs. 15.55 ± 14.91 days, p = 0.828) were similar for both rural and urban patients. There was a trend for rural patients to more likely be discharged home (35.96% vs. 29.79%, OR 0.667 [95% CI 0.479 – 0.929]; p = 0.0167).

Conclusions

This retrospective administrative database study indicated that rural and urban patients received equivalent postoperative care after undergoing esophagectomy. The findings were reassuring as there did not appear to be a disparity in major outcomes depending on the location of residence, but further studies are necessary to assure equitable treatment for rural patients.

Late cardiac toxicity of neo-adjuvant chemoradiation in esophageal cancer survivors: A prospective cross-sectional pilot study

PURPOSE

Although cure rates in esophageal cancer (EC) have improved since the introduction of neoadjuvant chemoradiation (nCRT), evidence for treatment-related cardiac toxicity is growing, of which the exact mechanisms remain unknown. The primary objective of this study was to identify (subclinical) cardiac dysfunction in EC patients after nCRT followed by surgical resection as compared to surgery alone.

MATERIALS AND METHODS

EC survivors followed for 5-15 years after curative resection with (n = 20) or without (n = 20) nCRT were enrolled in this prospective cross-sectional pilot study. All patients underwent several clinical and diagnostic tests in order to objectify (sub)clinical cardiac toxicity including cardiac CT and MRI, echocardiography, ECG, 6-minutes walking test, physical examination and EORTC questionnaires.

RESULTS

We found an increased rate of myocardial fibrosis (Linear late gadolinium enhancement (LGE) 4 vs. 1; p = 0.13; mean extracellular volume (ECV) 28.4 vs. 24.0; p < 0.01), atrial fibrillation (AF) (6 vs. 2; p = 0.07) and conduction changes in ECG among patients treated with nCRT as compared to those treated with surgery alone. The results suggested an impact on quality of life in terms of worse role functioning for this patient group (95.0 vs. 88.8; p = 0.03).

CONCLUSION

Based on our analyses we hypothesize that in EC patients, radiation-induced myocardial fibrosis plays a central role in cardiac toxicity leading to AF, conduction changes and ultimately to decreased role functioning. The results emphasize the need to verify these findings in larger cohorts of patients.

Effects of postoperative radiotherapy on cardiovascular-pulmonary disease mortality in patients with stage IIIA-N2 resected NSCLC: analysis of the SEER database

Background

The role of postoperative radiotherapy (PORT) in cardiovascular-pulmonary disease mortality in patients with stage IIIA-N2 resected non-small cell lung cancer (NSCLC) remains uncertain. The purpose of this population-based analysis was to explore the effect of PORT on cardiovascular-pulmonary disease mortality in these patients.

Methods

Patients aged ≥ 18 years with stage IIIA-N2 resected NSCLC were identified in the Surveillance, Epidemiology, and End Results (SEER) database from 2004 to 2015 and were grouped according to the use of PORT. Propensity score matching (PSM) was used to account for differences in baseline characteristics between the Non-PORT and PORT groups. The cumulative risk for cardiovascular-pulmonary disease death was estimated using the cumulative incidence curve. Competing risk regression was used to run univariate and multivariate analyses to evaluate risk factors.

Results

A total of 3981 patients were included in the study population. Among them, 1446 patients received PORT, and 2535 did not. A total of 1380 patients remained in each group after PSM, and the baseline characteristics were not significantly different between the two groups. The cumulative incidence of cardiovascular-pulmonary mortality was 10.93% in the Non-PORT group compared with 9.85% in the PORT group. There was no significant difference in the cumulative risk between the two groups (HR 1.07, 95% CI 0.77–1.48, p = 0.703). Multivariate analysis indicated that PORT had no significant impact on increased risk, with an HR of 1.18 (p = 0.377).

Conclusions

No significant differences between the PORT and Non-PORT groups were found in cardiovascular-pulmonary-specific modalities in this study. Further studies are required to validate these results. This study highlights the importance of long-term surveillance for NSCLC patients.

Impact of Radiation on Cardiovascular Outcomes in Older Resectable Esophageal Cancer Patients With Medicare

OBJECTIVES

Preoperative radiotherapy improves outcomes for operable esophageal cancer patients, though the proximity of the heart to the esophagus puts patients at risk of radiation-induced cardiovascular disease. This study characterizes the impact of radiotherapy and different radiation techniques on cardiovascular morbidity among a cohort of esophageal cancer patients.

MATERIALS AND METHODS

We identified 1125 patients aged 65 and older diagnosed between 2000 and 2011 with esophageal cancer who received surgery alone, or surgery preceded by either preoperative chemotherapy or preoperative chemoradiation from the Surveillance Epidemiology and End Results (SEER)-Medicare database. We used Medicare claims to identify severe perioperative and late cardiovascular events. Multivariable logistic regression and Fine-Gray models were used to determine the effect of presurgery treatment on the risk of perioperative and late cardiovascular disease.

RESULTS

Preoperative chemotherapy or chemoradiation did not significantly increase the risk of perioperative cardiovascular complications compared with surgery alone. Patients treated with preoperative chemoradiation had a 36% increased risk of having a late cardiovascular event compared with patients treated with surgery alone (subdistribution hazard ratio [SDHR]: 1.36; P=0.035). There was no significant increase in late cardiovascular events among patients treated with preoperative chemotherapy (SDHR: 1.18; P=0.40). Among patients treated with preoperative chemoradiation, those receiving intensity modulated radiotherapy had a 68% decreased risk of having a late cardiovascular event compared with patients receiving conventional radiation (SDHR: 0.32; P=0.007).

CONCLUSIONS

This study demonstrates an increased risk of cardiovascular complications among operative esophageal cancer patients treated with preoperative chemoradiation, though these risks might be reduced with more cardioprotective radiation techniques such as intensity modulated radiotherapy.

Proton therapy for thoracic malignancies: a review of oncologic outcomes

Introduction: Radiotherapy is an integral component in the treatment of the majority of thoracic malignancies. By taking advantage of the steep dose fall-off characteristic of protons combined with modern optimization and delivery techniques, proton beam therapy (PBT) has emerged as a potential tool to improve oncologic outcomes while reducing toxicities from treatment.Areas covered: We review the physical properties and treatment techniques that form the basis of PBT as applicable for thoracic malignancies, including a brief discussion on the recent advances that show promise to enhance treatment planning and delivery. The dosimetric advantages and clinical outcomes of PBT are critically reviewed for each of the major thoracic malignancies, including lung cancer, esophageal cancer, mesothelioma, thymic cancer, and primary mediastinal lymphoma.Expert opinion: Despite clear dosimetric benefits with PBT in thoracic radiotherapy, the improvement in clinical outcomes remains to be seen. Nevertheless, with the incorporation of newer techniques, PBT remains a promising modality and ongoing randomized studies will clarify its role to determine which patients with thoracic malignancies receive the most benefit. Re-irradiation, advanced disease requiring high cardio-pulmonary irradiation volume and younger patients will likely derive maximum benefit with modern PBT.

Proton beam radiotherapy for esophagus cancer: state of the art

The majority of esophageal cancer patients are diagnosed with locoregionally confined disease, which is often amenable to curative intent therapy. Chemoradiotherapy (CRT) improves overall survival (OS) in stage II and III esophagus cancer in the neoadjuvant and definitive settings. Due to the close proximity of organs at risk (OARs), including lungs, heart, stomach, bowel, kidneys, and spinal cord, esophageal CRT can result in profound acute and late toxicities. Acute toxicities can include esophagitis, nausea, vomiting, fatigue, and cytopenias. Late complications may also occur months or years after completion of thoracic radiotherapy, including significant cardiac, pulmonary, liver, kidney, or bowel toxicities, which can be life-threatening or fatal. Photon-based radiotherapy exposes OARs to significant doses of radiation, whereas proton beam therapy (PBT) has unique physical properties, as it lacks an exit dose. This allows PBT to deliver, a more conformal dose to the target and minimize the volume of OARs exposed to radiation. This dosimetric advantage may portend an increased therapeutic ratio of CRT for esophagus cancer. The objective of this review is to discuss the evolution of photon and proton-based radiotherapy techniques, rationale, dosimetric and clinical studies comparing outcomes of photon- and proton-based techniques, ongoing prospective trials, and future directions of PBT as a means of reducing toxicity and improving oncologic outcomes for patients with esophagus cancer.

Dose-Dependent Radiation-Induced Myocardial Damage in Esophageal Cancer Treated With Chemoradiotherapy: A Prospective Cardiac Magnetic Resonance Imaging Study

PURPOSE

The purpose of this prospective study was to evaluate radiation-induced myocardial damage after mediastinal radiation therapy (RT) using late gadolinium-enhancement (LGE) magnetic resonance imaging (MRI).

METHODS AND MATERIALS

We enrolled 19 patients with esophageal cancer who were expected to have long-term survival by definitive treatment. They underwent delayed contrast-enhanced MRI (19 patients before treatment, 19 patients 6 months after treatment, and 12 patients 1.5 years after treatment). Dose distribution of the left ventricle was made using computed tomography, and the dose volume histogram of the left ventricle was calculated. Myocardial signal intensities in individual MRIs were normalized by the mean values in regions receiving low doses (<5 Gy). Changes in the normalized signal intensities after mediastinal radiation therapy were compared among regions where irradiation doses were 0 to 10 Gy, 10 to 20 Gy, 20 to 30 Gy, 30 to 40 Gy, 40 to 50 Gy, and 50 to 60 Gy, and we investigated whether intensity change was detected in a dose-dependent manner.

RESULTS

The registered patients were treated with concurrent chemoradiotherapy with a median total dose of 60 Gy (50.4-66 Gy). Chemotherapy consisting of cisplatin and 5-fluorouracil was administered. In the population-based dose-response curve, dose-dependent intensity changes progressively increased in regions receiving more than 30 Gy. The averages of relative intensity change at 6 months and 1.5 years after treatment were 1.1% and -1.9% at 20 to 30 Gy and 37.5% and 17.5% at 40 to 50 Gy, respectively. LGE in regions receiving more than 30 Gy was detected in 68% (13/19) of the patients.

CONCLUSIONS

A dose-dependent relationship for myocardial signal intensity change was found by using LGE MRI. It may be necessary to reduce the volume of the myocardium receiving more than 30 Gy.

The Current Evidence on Neoadjuvant Therapy for Locally Advanced Esophageal Squamous Cell Carcinoma

Surgical resection is the mainstay of treatment for locally advanced esophageal cancer. Neoadjuvant therapy is recommended to improve survival, based on the results of several randomized trials and meta-analyses. However, controversy remains regarding how to combine surgery, radiotherapy, and chemotherapy. Moreover, in East Asia, the predominant histological type is esophageal squamous cell carcinoma, which has a different epidemiology and tumor biology from esophageal or gastroesophageal junctional adenocarcinoma. As such, the management of esophageal cancer in East Asia seems to be different from that in Western countries. Thus, this article reviews the current evidence on neoadjuvant therapy and considers the optimal combinations and ongoing strategies of multimodal therapy for esophageal squamous cell carcinoma.

Cardiac MRI utilizing late gadolinium enhancement (LGE) and T1 mapping in the detection of radiation induced heart disease

Background and purpose

Radiotherapy has been associated with late dose-dependent cardiovascular toxicity. In this cross-sectional pilot study, radiation dose distributions were correlated with areas of localized and diffuse myocardial fibrosis as measured by novel cardiac MRI (CMR) sequences including late gadolinium enhancement (LGE) and T1 mapping with the goal to identify early markers of myocardial damage.

Materials and methods

Twenty-eight patients with chest tumors including lung, breast, esophagus, and lymphoma underwent CMR per study protocol on average 46.4 months (range 1.7–344.5) after radiotherapy. Patients without pretreatment cardiac history were included if the volume of heart receiving 5 Gy or more was at least 10% (V5Gy ≥ 10%). The association of LGE with cardiac dosimetric factors, clinical factors (e.g., tumor type, smoking history, BMI), and T1 values was analyzed.

Results

Cardiac maximum (Dmax) and mean dose (Dmean) equivalent to doses delivered in 2 Gy fractions (EQD2) were on average 50.9 Gy (range 6.2–108.0) and 8.2 Gy (range 1.0–35.7), respectively, compared to 60.8 Gy (40.8–108.0) and 6.8 Gy (1.8–21.8) among the 9 patients with LGE. Doses were not different between patients with and without LGE (p = 0.16 and 0.56, respectively). The average T1 value of the left ventricle myocardium was 1009 ms (range 933–1117). No significant correlation was seen for heart Dmax and Dmean and T1 values (p = 0.14 and 0.58, respectively). In addition, no significant association between clinical factors and the development of LGE was identified.

Conclusions

No relation between cardiac doses, the presence of LGE or T1 values was observed. Further study is needed to determine the benefit of CMR for detecting radiotherapy-related myocardial fibrosis.

Effectiveness of salvage radiotherapy for superficial esophageal Cancer after non-curative endoscopic resection

BACKGROUND

Endoscopic resection is widely used as an effective treatment for superficial esophageal cancer. However, the risk of lymph node metastasis increases in cases of muscularis mucosae or deeper invasion, for which additional treatment such as radiotherapy or surgery is required. Accordingly, the current study investigated the efficacy and toxicity of salvage radiotherapy after non-curative endoscopic resection as an organ preservation strategy.

METHODS

We retrospectively reviewed 37 esophageal cancer patients who received salvage radiotherapy after non-curative endoscopic resection. The pathological invasion depths were the muscularis mucosae, submucosal layer, and muscularis propria in 14, 22, and one patient, respectively. All patients received external beam radiotherapy. Among them, eight received intraluminal brachytherapy following external beam radiotherapy. Elective nodal irradiation was administered to all patients. Twenty-five patients received concurrent platinum and fluorouracil-based chemotherapy.

RESULTS

The median follow-up time was 74 months (range: 3-212). The 5-year progression-free survival and overall survival rates were 64 and 78%, respectively. No local or regional lymph node recurrence was observed. The causes of death included esophageal cancer in one patient, metachronous esophageal cancer in one patient, other malignancies in eight patients, and other causes in six patients. Late cardiac toxicities ≥ grade 3 were observed in six patients, one of whom died of arrhythmia.

CONCLUSIONS

Salvage radiotherapy after non-curative esophageal endoscopic resection is an effective treatment as an organ preservation strategy. Although muscularis mucosae and submucosal cancer have a high risk of lymph node metastasis, our results suggest that elective nodal irradiation contributes to reduced regional node metastases.

Post-treatment mortality after definitive chemoradiotherapy versus resection for esophageal cancer

In efforts to better characterize incidence and predictors of 30- and 90-day mortality following operative versus nonoperative approaches for locally advanced esophageal cancer (EC), we conducted a novel investigation of a large, contemporary US database. The National Cancer Database was queried for newly-diagnosed T1-3N0-1 squamous cell or adenocarcinoma receiving surgical-based therapy (esophagectomy alone or preceded by chemotherapy and/or radiotherapy) versus definitive chemoradiotherapy (dCRT). Statistics included graphing cumulative incidences of mortality before and following propensity score matching (PSM), based on age-based intervals. Cox regression determined factors independently predictive of 30- and 90-day mortality. Of 15,585 patients, 9,278 (59.5%) received surgical-based therapy and 6,307 (40.5%) underwent dCRT. In the unadjusted population, despite nonsignificant differences at 30 days (3.3% dCRT, 3.6% surgical-based), the dCRT cohort experienced higher 90-day mortality (11.0% vs. 7.5%, P < 0.001). Following PSM, however, dCRT patients experienced significantly lower 30-day mortality (P < 0.001), with nonsignificant differences at 90 days (P = 0.092). Surgical-based management yielded similar (or better) mortality as dCRT in ≤70-year-old patients; however, dCRT was associated with reduced mortality in subjects > 70 years old. In addition to the intervention group, factors predictive for 30- and 90-day mortality included age, gender, insurance status, facility type, comorbidity index, tumor location, histology, and T/N classification. In summary, surgical-based therapy for EC is associated with higher 30-day mortality, which becomes statistically similar to dCRT by 90 days. Differences between surgery and dCRT were most pronounced in patients > 70 years of age. These data may better inform shared decision-making between multidisciplinary providers and patients.

Heart Dosimetric Parameters Were Associated With Cardiac Events and Overall Survival for Patients With Locally Advanced Esophageal Cancer Receiving Definitive Radiotherapy

Objectives: The aim of this study was to assess the association between heart dosimetric parameters and cardiac events or overall survival (OS) for patients with stage III esophageal cancer receiving definitive radiotherapy. Materials and Methods: Patients with stage III esophageal cancer receiving definitive radiotherapy at our hospital from 2011 to 2013 were enrolled retrospectively. The primary endpoint was grade ≥ 2 cardiac events, and the second endpoint was 5-year OS. Competing risk analysis and Cox regressions analysis were performed to evaluate the association between heart dose and cardiac events or OS. Results: Three hundred forty-six patients were analyzed. Median follow-up was 30 months. Median prescribed dose was 60 Gy. Seventy-eight patients (22.5%) had 91 grade ≥ 2 cardiac events, at a median of 14 months to first event. Thirty-three patients (9.5%) had 42 grade ≥ 3 cardiac events. Of the 78 patients with grade ≥ 2 cardiac events, 70 (89.7%) had the first cardiac events that occurred within first 3 years after radiotherapy. Multivariable analysis showed that preexisting ischemic heart disease [hazard ratio (HR), 2.26; 95% confidence interval (CI), 1.26-4.06; p = 0.006] and mean heart dose (HR, 1.12; 95% CI, 1.04-1.20; p = 0.002) were significantly associated with increased risk of grade ≥ 2 cardiac events. Disease progression (HR, 2.60; 95% CI, 1.82-3.70; p < 0.001), Eastern Cooperative Oncology Group (ECOG) performance status (HR, 0.71; 95% CI, 0.56-0.91; p = 0.007), heart volume receiving ≥ 5 Gy (V5, HR, 1.01; 95% CI, 1.00-1.03; p = 0.035), and gross tumor volume (GTV; HR, 1.00; 95% CI, 1.00-1.00; p = 0.020) were significant predictors of 5-year OS on multivariable analysis. Conclusion: Higher heart dose was significantly associated with an increased cardiac event rate and a worse OS outcome for patients with stage III esophageal cancer treated with definitive radiotherapy. Most of the first cardiac events occurred within first 3 years after treatment.

Randomized Phase IIB Trial of Proton Beam Therapy Versus Intensity-Modulated Radiation Therapy for Locally Advanced Esophageal Cancer

PURPOSE

Whether dosimetric advantages of proton beam therapy (PBT) translate to improved clinical outcomes compared with intensity-modulated radiation therapy (IMRT) remains unclear. This randomized trial compared total toxicity burden (TTB) and progression-free survival (PFS) between these modalities for esophageal cancer.

METHODS

This phase IIB trial randomly assigned patients to PBT or IMRT (50.4 Gy), stratified for histology, resectability, induction chemotherapy, and stage. The prespecified coprimary end points were TTB and PFS. TTB, a composite score of 11 distinct adverse events (AEs), including common toxicities as well as postoperative complications (POCs) in operated patients, quantified the extent of AE severity experienced over the duration of 1 year following treatment. The trial was conducted using Bayesian group sequential design with three planned interim analyses at 33%, 50%, and 67% of expected accrual (adjusted for follow-up).

RESULTS

This trial (commenced April 2012) was approved for closure and analysis upon activation of NRG-GI006 in March 2019, which occurred immediately prior to the planned 67% interim analysis. Altogether, 145 patients were randomly assigned (72 IMRT, 73 PBT), and 107 patients (61 IMRT, 46 PBT) were evaluable. Median follow-up was 44.1 months. Fifty-one patients (30 IMRT, 21 PBT) underwent esophagectomy; 80% of PBT was passive scattering. The posterior mean TTB was 2.3 times higher for IMRT (39.9; 95% highest posterior density interval, 26.2-54.9) than PBT (17.4; 10.5-25.0). The mean POC score was 7.6 times higher for IMRT (19.1; 7.3-32.3) versus PBT (2.5; 0.3-5.2). The posterior probability that mean TTB was lower for PBT compared with IMRT was 0.9989, which exceeded the trial's stopping boundary of 0.9942 at the 67% interim analysis. The 3-year PFS rate (50.8% v 51.2%) and 3-year overall survival rates (44.5% v 44.5%) were similar.

CONCLUSION

For locally advanced esophageal cancer, PBT reduced the risk and severity of AEs compared with IMRT while maintaining similar PFS.

Cardiac Toxicity in Operable Esophageal Cancer Patients Treated With or Without Chemoradiation

PURPOSE

The purpose of this study was to evaluate predictors of cardiac events in esophageal cancer patients treated with neoadjuvant chemoradiotherapy (NA CRT) followed by surgery compared with surgery alone.

MATERIALS AND METHODS

We retrospectively identified patients treated for esophageal cancer between 2006 and 2016. A total of 123 patients were identified; 70 were treated with surgery alone, and 53 were treated with NA CRT. Cardiac events were scored based on Common Terminology Criteria for Adverse Events (version 4.03), and dosimetric data was compiled for all patients who received radiation. Univariate analysis and multivariable analysis (MVA) were performed to identify predictors of cardiac events. Competing risk of death regression was performed to a model the cumulative incidence of cardiac events.

RESULTS

The overall rates of grade ≥3 cardiac events were 24.5% in the NA CRT group versus 10% in the surgery group (P=0.04). On MVA, use of NA CRT (P<0.01, hazard ratio [HR]: 3.45, 95% confidence interval [CI]: 1.35-9.09) predicted for grade ≥3 cardiac events, though no dosimetric variable predicted for grade ≥3 cardiac events or overall survival. On MVA, NA CRT predicted for pericardial effusions of any grade (P<0.01, HR: 3.70, 95% CI: 1.67-8.33). The V45 Gy was the most significant predictor of pericardial effusions (P=0.012, HR: 1.03, 95% CI: 1.01-1.06) CONCLUSIONS:: NA CRT significantly increased the rate of grade ≥3 cardiac events compared with patients treated with surgery alone. Although no dosimetric parameter predicted for grade ≥3 cardiac events or survival, the V45 Gy predicted for pericardial effusions.

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.

Patterns of Care and Outcomes of Elderly Esophageal Cancer Patients Not Meeting Age-based Criteria of the CROSS Trial

OBJECTIVES

The CROSS trial established neoadjuvant chemoradiation followed by surgery (nCRT-S) as superior to surgery alone (S) for locally advanced esophageal cancer (EC). However, because patients above 75 years of age were excluded, this comparison cannot be extrapolated to older patients. This study of a large, contemporary national database evaluated practice patterns in elderly patients ineligible for CROSS, and analyzed overall survival (OS) between nCRT+S, S, and definitive CRT (dCRT).

MATERIALS AND METHODS

The National Cancer Data Base was queried for EC patients with cT1N1M0/T2-3N0-1M0 EC (per the CROSS trial) but 76 years and above of age. Multivariable logistic regression ascertained factors associated with nCRT+S (vs. S). Kaplan-Meier analysis evaluated OS; Cox multivariate analysis determined variables associated with OS. Propensity matching aimed to address group imbalances and indication biases.

RESULTS

Of 4099 total patients, 594 (14%) underwent nCRT+S, 494 (12%) underwent S, and 3011 (73%) underwent dCRT. Since 2010, trimodality management has risen, corresponding to declines in S and dCRT. Median OS in the respective groups were 26.7, 20.3, and 17.8 months (P<0.05). Following propensity matching, there was a trend towards higher OS with nCRT-S over S (P=0.077); dCRT showed poorer OS than nCRT-S (P<0.001) but was equivalent to S (P=0.669). Before and following matching, nCRT-S experienced equivalent 30- and 90-day mortality as S (P>0.05), with lower 30-day readmission and postoperative hospital stay (P<0.05).

CONCLUSIONS

Although most older patients not meeting CROSS criteria undergo dCRT, utilization of trimodality therapy is rising. Despite the trend towards higher OS with trimodality therapy without poorer postoperative outcomes, careful patient selection continues to be essential in this population.

Intensity-modulated radiotherapy at high-volume centers improves survival in patients with esophageal adenocarcinoma receiving trimodality therapy

The standard of care trimodality therapy for resectable locally advanced esophageal adenocarcinoma is complex and necessitates multidisciplinary care and expertise. In this work, it is hypothesized that facility clinical volume and utilization of intensity-modulated radiotherapy (IMRT) may influence outcomes. The National Cancer Data Base was queried for patients with cT1-4-N0-3 M0 esophageal adenocarcinoma undergoing trimodality therapy from 2004 to 2013 (n = 2445). All patients received chemoradiation followed by esophagectomy at a Commission on Cancer facility. The facility volume was categorized into tertiles: high-volume centers (HVCs) in the highest 25th percentile of cases per year, intermediate-volume centers (IVCs) with the next highest 25th percentile of cases, and low- and very low-volume centers (LVCs) in the lowest 50th percentile. Overall survival (OS) was estimated using Kaplan-Meier methods and Cox proportional hazard regression. Propensity score matching to balance patient characteristics between volume centers was performed. Subgroup analysis was done comparing IMRT versus 3D conformal radiotherapy. The median follow-up was 26 months. Treatment at an HVC (hazard ratio 0.63, 95% CI 0.49-0.81, P < 0.001) was found to be independently associated with improved overall survival in multivariable analysis. Three-year OS was 58.4%, 46.2%, and 47.5% for HVCs, IVCs, and LVCs, respectively (P < 0.001). Patients at HVCs were more likely to receive IMRT over 3D chemoradiation (CRT; OR 3.45, 95% CI 2.4-5.0, P < 0.001). Patients treated using IMRT at HVCs had improved OS compared to those treated at IVCs or LVCs (HR 0.68, 95% CI 0.52-0.90, P < 0.01), while patients treated with 3D CRT at HVCs had no survival advantage over those at IVCs or LVCs (P = 0.28). Patients with locally advanced esophageal adenocarcinoma treated with IMRT and at HVCs appear to have improved survival.

Comparative study of esophagectomy, endoscopic therapy, and radiotherapy for cT1N0M0 esophageal cancer in elderly patients: A SEER database analysis

BACKGROUND

The number of patients diagnosed with early stage disease (T1a or T1b) has been increasing. This study was conducted to investigate the effect of esophagectomy (ES), endoscopic therapy (ET), and radiotherapy (RT) on long-term survival in elderly patients with cT1N0M0 esophageal cancer.

METHODS

We searched the Surveillance, Epidemiology, and End Results (SEER) database to identify the records of elderly patients (≥ 75 years) with cT1N0M0 esophageal cancer between 2004 and 2014. Patient demographics and esophageal cancer parameters were compared among ES, ET, and RT groups. The Kaplan-Meier method and Cox proportional hazard modeling were used to compare long-term survival.

RESULTS

Data from 954 esophageal cancer patients (ES: n = 196; ET: n = 224; RT: n = 534) were identified. Multivariate Cox regression analysis showed that five-year survival in the ET and ES groups was significantly higher than in the RT group. After propensity score matching, we found no difference in five-year survival between ES and ET.

CONCLUSION

Using SEER data, we identified a significant survival advantage with the use of ES and ET compared to RT in patients with cT1N0M0 esophageal cancer aged > 75 years, while the long-term survival of patients after ET and ES was not significantly different.

Trimodality therapy for esophageal cancer at high volume facilities is associated with improved postoperative outcomes and overall survival

Trimodality therapy is the standard of care for locally advanced resectable esophageal cancer (EC) but carries morbidity and mortality risks; thus, therapy at high-volume facilities (HVFs) may offer advantages. This investigation studied postoperative outcomes and overall survival (OS) in EC patients receiving trimodality therapy at HVFs versus lower-volume facilities (LVFs). The National Cancer Data Base was queried for patients with locally advanced EC receiving trimodality therapy. HVFs referred to the 90th percentile of case volume. Multivariate logistic regression determined factors associated with treatment at HVFs, the Kaplan-Meier analysis compared OS between the HVF and LVF groups, and the Cox proportional hazards modeling determined variables associated with OS. Sensitivity analysis evaluated the impact of varying the HVF definition cutoff on OS. A total of 3,229 patients met study criteria, including 330 (10%) treated at HVFs and 2,899 (90%) at LVFs. Treatment at HVFs was associated with decreased 30-day mortality (1.2% vs. 3.3%, P = 0.044) and trends toward lower 90-day mortality (4.8% vs. 7.8%, P = 0.055) and the length of postoperative hospitalization (11.2 vs. 12.3d, P = 0.059). HVF patients experienced higher median OS (55 vs. 36 months, P = 0.004), which also independently correlated on the Cox multivariate analysis (P = 0.001). Sensitivity analysis showed similar results as the HVF/LVF cutoff was decreased until the 80th percentile. This is the first study demonstrating that the trimodality management of EC at HVFs is associated with improved postoperative outcomes and survival. These data have implications for multidisciplinary oncologic providers, in addition to patient counseling by both referring and treating clinicians.

Volumetric modulated arc therapy (VMAT) in the treatment of esophageal cancer patients

The aim of the study is to evaluate feasibility, safety, toxicity profile, and dosimetric results of volumetric modulated arc therapy (VMAT) to deliver definitive or pre-operative radiation in locally advanced esophageal cancer patients. A total of 68 patients were treated with VMAT between March 2014 and March 2018 (44% vs 56% for definitive and neoadjuvant settings, respectively). Dose prescription differed depending on the clinical scenario (54-60 Gy in 30 fractions for definitive treatments; 41.4/45 Gy in 23-25 fractions in the pre-operative setting). Most of the patients were given concurrent chemotherapy. Two coplanar and one non-coplanar arcs were employed for VMAT delivery. Treatment was generally well tolerated. Acute toxicity was generally mild. In patients treated with definitive intent, ≥ G3 toxicities were observed for esophagitis (30%), anorexia (26.7%), fatigue (26.7%), nausea (6.7%), and vomiting (3.3%). In patients treated within a neoadjuvant approach, ≥ G3 anorexia (21%), esophagitis (15.8%), fatigue (13.3%), nausea (5.3%), and vomiting (2.6%) were observed. Dosimetric results were consistent in term of both target coverage and normal tissue sparing. In conclusion, VMAT proved to be a feasible, safe, and effective strategy to deliver definitive or pre-operative radiation in locally advanced esophageal cancer patients.

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.

Quantifying esophageal motion during free-breathing and breath-hold using fiducial markers in patients with early-stage esophageal cancer

Introduction

Cardiac toxicity after definitive chemoradiotherapy for esophageal cancer is a critical issue. To reduce irradiation doses to organs at risk, individual internal margins need to be identified and minimized. The purpose of this study was to quantify esophageal motion using fiducial makers based on four-dimensional computed tomography, and to evaluate the inter-CBCT session marker displacement using breath-hold.

Materials and methods

Sixteen patients with early stage esophageal cancer, who received endoscopy-guided metallic marker placement for treatment planning, were included; there were 35 markers in total, with 9, 15, and 11 markers in the upper thoracic, middle thoracic, and lower thoracic/esophagogastric junction regions, respectively. We defined fiducial marker motion as motion of the centroidal point of the markers. Respiratory esophageal motion during free-breathing was defined as the amplitude of individual marker motion between the consecutive breathing and end-expiration phases, derived from four-dimensional computed tomography. The inter-CBCT session marker displacement using breath-hold was defined as the amplitudes of marker motion between the first and each cone beam computed tomography image. Marker motion was analyzed in the three regions (upper thoracic, middle thoracic, and lower thoracic/esophagogastric junction) and in three orthogonal directions (right-left; anterior-posterior; and superior-inferior).

Results

Respiratory esophageal motion during free-breathing resulted in median absolute maximum amplitudes (interquartile range), in right-left, anterior-posterior, and superior-inferior directions, of 1.7 (1.4) mm, 2.0 (1.5) mm, and 3.6 (4.1) mm, respectively, in the upper thoracic region, 0.8 (1.1) mm, 1.4 (1.2) mm, and 4.8 (3.6) mm, respectively, in the middle thoracic region, and 1.8 (0.8) mm, 1.9 (2.0) mm, and 8.0 (4.5) mm, respectively, in the lower thoracic/esophagogastric region. The inter-CBCT session marker displacement using breath-hold resulted in median absolute maximum amplitudes (interquartile range), in right-left, anterior–posterior, and superior-inferior directions, of 1.3 (1.0) mm, 1.1 (0.7) mm, and 3.3 (1.8) mm, respectively, in the upper thoracic region, 0.7 (0.7) mm, 1.1 (0.4) mm, and 3.4 (1.4) mm, respectively, in the middle thoracic region, and 2.0 (0.8) mm, 2.6 (2.2) mm, and 3.5 (1.8) mm, respectively, in the lower thoracic/esophagogastric region.

Conclusions

During free-breathing, esophageal motion in the superior-inferior direction in all sites was large, compared to the other directions, and amplitudes showed substantial inter-individual variability. The breath-hold technique is feasible for minimizing esophageal displacement during radiotherapy in patients with esophageal cancer.

Comparison of intensity-modulated radiotherapy vs 3-dimensional conformal radiotherapy for patients with non-metastatic esophageal squamous cell carcinoma receiving definitive concurrent chemoradiotherapy: A population-based propensity-score-matched analysis

Whether the survival outcome of patients with non-metastatic esophageal squamous cell carcinoma (NM-ESCC) receiving definitive concurrent chemoradiotherapy (CCRT) is better with intensity-modulated radiotherapy (IMRT) or with 3-dimensional conformal radiotherapy (3DCRT) has been debated in the literature. We designed this population-based propensity-score (PS)-matched analysis to address this question. We identified eligible patients diagnosed between 2008 and 2015 from the Taiwan Cancer Registry and constructed a PS-matched cohort (1:1 for IMRT vs 3DCRT) to balance observable potential confounders. We compared the hazard ratio (HR) of death between IMRT and 3DCRT during the entire follow-up period. We also evaluated freedom from local regional recurrence (FFLRR) and esophageal cancer-specific survival (ECSS). Sensitivity analyses (SA) were performed to examine the robustness of our findings. Our study population constituted 558 patients who were well balanced with regard to the measured covariables. The HR of death with IMRT compared to 3DCRT was 0.43 (95% confidence interval 0.35-0.52, P < .001). The results remained significant for FFLRR and ECSS. In SA, our results remained significant when additional covariables were taken into consideration. The survival outcome of patients with NM-ESCC receiving CCRT might be better with IMRT vs 3DCRT. These study results should be interpreted with caution given some possible covariates lacking in the registry. Further studies are needed to clarify this issue.

Neoadjuvant chemoradiation radiation dose levels for surgically resectable esophageal cancer: predictors of use and outcomes

Neoadjuvant chemoradiation (CRT) followed by surgical resection is the standard of care for resectable, locally advanced esophageal cancer. There are promising results using 41.4 Gy relative to historical controls using higher doses, but the utilization and efficacy of lower neoadjuvant radiation dosing is unclear. This study uses the National Cancer Database (NCDB) to explore patterns of care for neoadjuvant CRT dose levels and outcomes. The NCDB was queried for localized invasive esophageal adenocarcinoma (AC) or squamous cell carcinoma (SCC) receiving neoadjuvant CRT with doses from 40 to 54 Gy followed by surgical resection. Patients were divided into radiation levels: 40-41.4, 45, 50.4, and 54 Gy, respectively. Factors predicting use of 40-41.4 Gy vs. all other dose levels were compared using multivariable logistic regression. Factors affecting overall survival (OS) were compared using univariate and multivariate modeling. A total of 6,274 patients with AC (n = 5,176) or SCC (n = 1,098) receiving neoadjuvant CRT and definitive resection were identified. Hispanic race (OR 2.67 [95% CI 1.22-5.81]) and treatment at an academic center (OR 2.72 [95% CI 1.15-6.41]) predicted for use of low-dose CRT. Lower dose CRT increased from 3.9% in 2004 to 7.2% in 2013. There was no difference in OS when stratified according to radiation dose level (P = 0.48). Multivariable analysis found private/government insurance, higher education, higher median income, and treatment at an academic center were associated with improved OS. Age, male gender, Charlson-Deyo comorbidity score, stage, tumor grade, and treatment in the South were associated with worse OS. Use of lower neoadjuvant CRT dose is more common at academic centers and shows possible increasing usage. Neoadjuvant radiation dose for esophageal cancer is not associated with differences in OS in this large database.

The Changing Paradigm of Radiotherapy in the Elderly Population

There is increasing awareness of the special needs for care of the elderly cancer patient. Newer precise conformal radiotherapy techniques allow the safe delivery of higher doses of radiotherapy to the target tumor while reducing the dose to surrounding critical organs. This has led to a shortening of radiotherapy protocols for both curative and palliative indications. We review these novel techniques and protocols and the published clinical studies that include elderly patients treated with these techniques. Despite the fact that the elderly are a growing significant proportion of cancer patients, and the need for radiotherapy in the elderly is expected to rise with increasing life expectancy, they are underrepresented in most clinical studies of radiotherapy, and there are few studies specifically investigating radiotherapy in the elderly. The treatment of early-stage primary lung cancer with stereotactic body radiotherapy is a prime example how new highly conformal techniques and shortened treatment protocols are changing the approach to radiotherapy in the elderly. With improved imaging and radiotherapy treatment precision, it is expected that such techniques will become increasingly used in other cancer sites. It is important for radiation oncologists to be aware of the special needs of the elderly cancer patient and in particular to assess these patients based on functional status and not only chronological age. In addition, geriatric oncologists should be aware of modern radiotherapy techniques that can be particularly appropriate for the elderly patient.

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.

Treatment disparities affect outcomes for patients with stage I esophageal cancer: a national cancer data base analysis

Background

To examine patterns of care and outcomes for patients with stage I esophageal cancer (EC) in the United States.

Methods

We identified patients in the National Cancer Data Base diagnosed with stage I EC from 2004 to 2012 and grouped them by primary treatment: esophagectomy (Eso), local excision (LE), concurrent chemoradiation (CRT), or observation (Obs). Multinomial logistic regression was used to predict receipt of treatments. Overall survival (OS) was estimated by Kaplan-Meier methods adjusted for inverse probability of treatment weighting (IPTW) and Cox proportional hazard regressions.

Results

Of 5,480 patients, 2,312 (42%) underwent Eso, 1,250 (23%) LE, 758 (14%) CRT, and 1,160 (21%) Obs. LE use increased over time from 17% to 29% while Obs declined from 26% to 19%. Patients least likely to undergo surgery were older, had greater comorbidity, were uninsured, were treated at non-academic centers, and were Black. The rate of surgery for Black patients was half of that for White patients (33% vs. 67%). Postoperative mortality rates were higher after Eso vs. LE at 30 days (2.9% vs. 0.5%; P<0.001) and at 90 days (5.5% vs. 1.4%, P<0.001). Five-year OS was 59% with Eso, 63% LE, 29% CRT, and 31% Obs (P<0.001). On multivariate analysis, outcomes were best after LE [vs. Eso: hazard ratio (HR) =1.15, 95% CI: 1.01-1.30, P=0.037; CRT: HR =2.41, 95% CI: 2.09-2.78, P<0.001; Obs: HR =3.79, 95% CI: 3.33-4.32, P<0.001).

Conclusions

Disparities are evident in the care of patients with stage I EC throughout the United States. LE was associated with favorable outcomes compared to Eso, CRT, and Obs.

Managing an Older Adult with Cancer: Considerations for Radiation Oncologists

Older adults with cancer present a unique set of management complexities for oncologists and radiation oncologists. Prognosis and resilience to cancer treatments are notably dependent on the presence or risk of "geriatric syndromes," in addition to cancer stage and histology. Recognition, proper evaluation, and management of these conditions in conjunction with management of the cancer itself are critical and can be accomplished by utilization of various geriatric assessment tools. Here we review principles of the geriatric assessment, common geriatric syndromes, and application of these concepts to multidisciplinary oncologic treatment. Older patients may experience toxicities related to treatments that impact treatment effectiveness, quality of life, treatment-related mortality, and treatment compliance. Treatment-related burdens from radiotherapy are increasingly important considerations and include procedural demands, travel, costs, and temporary or permanent loss of functional independence. An overall approach to delivering radiotherapy to an older cancer patient requires a comprehensive assessment of both physical and nonphysical factors that may impact treatment outcome. Patient and family-centered communication is also an important part of developing a shared understanding of illness and reasonable expectations of treatment.

Dosimetric and clinical outcomes after volumetric modulated arc therapy for carcinoma of the thoracic esophagus

Purpose

The efficiency of radiation delivery via volumetric modulated arc therapy (VMAT) is indisputable, but outcomes after VMAT for thoracic esophageal carcinoma are largely unknown.

Methods and materials

We retrospectively analyzed 65 patients with thoracic esophageal cancer who received VMAT to 50.4 Gy (range, 45-50.4 Gy) with concurrent chemotherapy from November 2012 to March 2016 at a single tertiary cancer center. We then used propensity score matching to match these 65 patients with 130 other patients treated with step-and-shoot intensity modulated radiation therapy (ssIMRT) and concurrent chemotherapy. Differences in continuous and categorical variables were examined with independent-sample t or Wilcoxon tests and χ² tests.

Results

Dosimetrically, VMAT had a higher conformity index (87.75 ± 10.70 VMAT vs 83.20 ± 9.42 ssIMRT, P = .003), a higher heart V5, and a lower V50 than ssIMRT, but lung V5-20, heart V30, heart V40, cord_max, and homogeneity index were similar. At median follow-up intervals of 14.3 months (range, 3.8-34.5 months) for VMAT and 31.8 months (range, 1.8-117.2 months) for ssIMRT, overall survival rates were similar between the treatments (93.5% VMAT vs 91.5% ssIMRT at 1 year; 60.0% VMAT and 61.4% ssIMRT at 2 years; P = .868). Recurrence-free survival rates were similar (73.3% VMAT vs 79.5% ssIMRT at 1 year, 59.9% VMAT and 61.8% ssIMRT at 2 years; P = .614), as were pathologic complete response rates (31.2% VMAT vs 23.3% ssIMRT; P = .41) and toxicity and postoperative complications (radiation pneumonitis 9% VMAT vs 15.4% ssIMRT; pericardial effusion 2% VMAT vs 7% ssIMRT; esophageal fistula and stricture 9% VMAT vs 13% ssIMRT; all P > .05).

Conclusion

Compared with ssIMRT, VMAT had better target conformity with similar organ sparing and comparable rates of survival, recurrence, and toxicity. These results suggest that VMAT can be safe and effective for esophageal cancer.