Clinical and dosimetric predictors of radiation-induced esophageal toxicity

Esophagitis and Pneumonitis Related to Concurrent Chemoradiation ± Durvalumab Consolidation in Unresectable Stage III Non-Small-Cell Lung Cancer: Risk Assessment and Management Recommendations Based on a Modified Delphi Process

The addition of durvalumab consolidation to concurrent chemoradiation therapy (cCRT) has fundamentally changed the standard of care for patients with unresectable stage III non-small-cell lung cancer (NSCLC). Nevertheless, concerns related to esophagitis and pneumonitis potentially impact the broad application of all regimen components. A Canadian expert working group (EWG) was convened to provide guidance to healthcare professionals (HCPs) managing these adverse events (AEs) and to help optimize the patient experience. Integrating literature review findings and real-world clinical experience, the EWG used a modified Delphi process to develop 12 clinical questions, 30 recommendations, and a risk-stratification guide. The recommendations address risk factors associated with developing esophagitis and pneumonitis, approaches to risk mitigation and optimal management, and considerations related to initiation and re-initiation of durvalumab consolidation therapy. For both AEs, the EWG emphasized the importance of upfront risk assessment to inform the treatment approach, integration of preventative measures, and prompt initiation of suitable therapy in alignment with AE grade. The EWG also underscored the need for timely, effective communication between multidisciplinary team members and clarity on responsibilities. These recommendations will help support HCP decision-making related to esophagitis and pneumonitis arising from cCRT ± durvalumab and improve outcomes for patients with unresectable stage III NSCLC.

Factors associated with acute esophagitis during radiation therapy for lung cancer

INTRODUCTION

Limiting acute esophagitis remains a clinical challenge during the treatment of locally advanced non-small cell lung cancer (NSCLC).

METHODS

Demographic, dosimetric, and acute toxicity data were prospectively collected for patients undergoing definitive radiation therapy +/- chemotherapy for stage II-III NSCLC from 2012 to 2022 across a statewide consortium. Logistic regression models were used to characterize the risk of grade 2 + and 3 + esophagitis as a function of dosimetric and clinical covariates. Multivariate regression models were fitted to predict the 50 % risk of grade 2 esophagitis and 3 % risk of grade 3 esophagitis.

RESULTS

Of 1760 patients, 84.2 % had stage III disease and 85.3 % received concurrent chemotherapy. 79.2 % of patients had an ECOG performance status ≤ 1. Overall rates of acute grade 2 + and 3 + esophagitis were 48.4 % and 2.2 %, respectively. On multivariate analyses, performance status, mean esophageal dose (MED) and minimum dose to the 2 cc of esophagus receiving the highest dose (D2cc) were significantly associated with grade 2 + and 3 + esophagitis. Concurrent chemotherapy was associated with grade 2 + but not grade 3 + esophagitis. For all patients, MED of 29 Gy and D2cc of 61 Gy corresponded to a 3 % risk of acute grade 3 + esophagitis. For patients receiving chemotherapy, MED of 22 Gy and D2cc of 50 Gy corresponded to a 50 % risk of acute grade 2 + esophagitis.

CONCLUSIONS

Performance status, concurrent chemotherapy, MED and D2cc are associated with acute esophagitis during definitive treatment of NSCLC. Models that quantitatively account for these factors can be useful in individualizing radiation plans.

Association of Radiation-Induced Acute Esophagitis With Dosimetric Parameters of Oesophagus in Breast Carcinoma Patients Receiving Supraclavicular Nodal Irradiation

INTRODUCTION

We conducted this investigation to ascertain the dosimetric properties such as the mean and maximum radiation dosage during radiotherapy as well as the extent of radiation exposure to the esophagus. These factors can potentially impact the development of esophagitis in breast cancer patients undergoing supraclavicular radiation.

METHODOLOGY

 From January to June 2023, an observational study was conducted at Bangabandhu Sheikh Mujib Medical University in Bangladesh. The patients received radiation therapy (40.05 Gy in 15 parts) to the chest wall and supraclavicular node for three weeks. We were able to guess the following from the dose volume histogram (DVH) data: the length of the esophagus in the treatment area (i.e., the size of the esophagus that was visible on the planning CT scan), the maximum dose (Dmax), the mean dose (Dmean), and the volume of the 10Gy (V10Gy) and 20Gy (V20Gy) doses that were given to the esophagus. During radiotherapy, patients were checked on once a week, and the radiotherapy oncology group was used to evaluate and grade esophagitis Results: Patients with left-sided breast cancer showed a higher Dmean, Dmax, and length of the esophagus compared to those with right-sided breast cancer. Specifically, the Dmean was 6.7 (±2.1) Gy, the Dmax was 39.2 (±1.5) Gy, and the length of the esophagus was 6.1 (±1.2) Gy. Patients with left breast cancer had elevated V10Gy and V20Gy values for the esophagus, but the difference was not statistically significant. The incidence of V10Gy for right-sided breast cancer and left-sided breast cancer was 4.2% (±2.6%) and 19.8% (±9.2%), respectively. The V20Gy was 2.4% (±0.9%) for right-sided breast cancer and 13.09% (±5.0%) for left-sided breast cancer Conclusion: In conclusion, there is a strong association between the mean oesophageal dose and radiation to the left supraclavicular region following surgery in women with breast cancer and acute esophagitis. We can reduce esophageal toxicity by prescribing dose restrictions and performing precise delineation of the esophagus.

Outcomes following hypofractionated radiation therapy alone for surgically unfit early esophageal squamous cell carcinoma patients; a retrospective single center analysis

BACKGROUND AND PURPOSE

To report the feasibility of hypofractionated radiation therapy (RT) alone for early stage esophageal squamous cell carcinoma (ESCC) patients.

MATERIALS AND METHODS

The oncologic outcomes of 60 cT1-2 N0 ESCC patients who received hypofractionated RT (54 ∼ 60 Gy by 3.0 Gy per fraction) from 2004 to 2018 were retrospectively evaluated.

RESULTS

The 5-year rates of local control (LC), progression-free survival, cancer-specific survival, and overall survival were 81.1 %, 44.2 %, 73.7 %, and 54.5 %, respectively. In Cox regression analysis, tumor length < 3 cm was correlated with favorable LC (HR 0.167, p = 0.090), and the 5-year LC rates were 95.7 % and 72.0 % in < 3 cm and ≥ 3 cm subgroups, respectively (p = 0.053). Grade ≥ 2 esophagitis was observed in 44 patients (73.3 %) and grade ≥ 2 esophageal strictures developed in five (8.3 %), respectively. The patients with ≥ 3 cm tumor more frequently suffered from grade ≥ 2 esophagitis (13/24 vs. 31/36, p = 0.006) and grade ≥ 2 esophageal stricture (0/24 vs. 5/36, p = 0.056), respectively. The patients with cT2 tumor suffered from grade ≥ 2 esophagitis more frequently than those with T1 tumor (29/44 vs. 15/16, p = 0.03).

CONCLUSIONS

Hypofractionated RT alone, with the merit of short treatment course, could be used as feasible option in treating the early stage ESCC patients who are unfit for surgical resection or chemoradiation. Especially, tumor length < 3 cm seems a good indication of this treatment scheme based on favorable LC rate with low incidence of esophageal toxicities.

Obtaining organ-specific radiobiological parameters from clinical data for radiation therapy planning of head and neck cancers

Objective.Different radiation therapy (RT) strategies, e.g. conventional fractionation RT (CFRT), hypofractionation RT (HFRT), stereotactic body RT (SBRT), adaptive RT, and re-irradiation are often used to treat head and neck (HN) cancers. Combining and/or comparing these strategies requires calculating biological effective dose (BED). The purpose of this study is to develop a practical process to estimate organ-specific radiobiologic model parameters that may be used for BED calculations in individualized RT planning for HN cancers.Approach.Clinical dose constraint data for CFRT, HFRT and SBRT for 5 organs at risk (OARs) namely spinal cord, brainstem, brachial plexus, optic pathway, and esophagus obtained from literature were analyzed. These clinical data correspond to a particular endpoint. The linear-quadratic (LQ) and linear-quadratic-linear (LQ-L) models were used to fit these clinical data and extract relevant model parameters (alpha/beta ratio, gamma/alpha,dTand BED) from the iso-effective curve. The dose constraints in terms of equivalent physical dose in 2 Gy-fraction (EQD2) were calculated using the obtained parameters.Main results.The LQ-L and LQ models fitted clinical data well from the CFRT to SBRT with the LQ-L representing a better fit for most of the OARs. The alpha/beta values for LQ-L (LQ) were found to be 2.72 (2.11) Gy, 0.55 (0.30) Gy, 2.82 (2.90) Gy, 6.57 (3.86) Gy, 5.38 (4.71) Gy, and the dose constraint EQD2 were 55.91 (54.90) Gy, 57.35 (56.79) Gy, 57.54 (56.35) Gy, 60.13 (59.72) Gy and 65.66 (64.50) Gy for spinal cord, optic pathway, brainstem, brachial plexus, and esophagus, respectively. Additional two LQ-L parametersdTwere 5.24 Gy, 5.09 Gy, 7.00 Gy, 5.23 Gy, and 6.16 Gy, and gamma/alpha were 7.91, 34.02, 8.67, 5.62 and 4.95.Significance.A practical process was developed to extract organ-specific radiobiological model parameters from clinical data. The obtained parameters can be used for biologically based radiation planning such as calculating dose constraints of different fractionation regimens.

Prediction Factors of Radiation Esophagitis in Breast Cancer Patients Undergoing Supraclavicular Radiotherapy

Purpose

The aim of this study was to investigate demographic and dosimetric parameters which may link with esophagitis in patients with breast cancer receiving three-dimensional conformal radiotherapy to the supraclavicular fossa.

Materials and Methods

We examined 27 breast cancer patients with supraclavicular metastases. All patients were treated with radiotherapy (RT) with a prescribed dose of 40.5 Gy in 15 fractions for 3 weeks. Esophagitis was recorded weekly and esophagus toxicity was evaluated and graded according to the tadiation therapy oncology group. The following factors were examined regarding their correlation with grade 1 or worse esophagitis by univariate and multivariate analyses: age, chemotherapy, smoking history, maximum dose (Dmax), mean dose (Dmean), esophagus volume receiving 10 Gy (V10), esophagus volume receiving 20 Gy (V20), and length of esophagus in the treatment field.

Results

Of 27, 11 (40.7%) patients developed no esophageal irritation throughout therapy. Approximately half of the patients 13/27 (48.1%) had maximum grade 1 esophagitis. 2/27 (7.4%) patients had grade 2 esophagitis. The incidence of grade 3 esophagitis was (3.7%). Dmean, Dmax, V10, and V20 were 10.48 ± 5.10 Gy, 38.18 ± 5.12Gy, 29.83 ± 15.16, and 19.32 ± 10.01, respectively. Our results showed that Dmean, V10, and V20 were the significant factors for the development of esophagitis, whereas esophagitis was not significantly associated with the chemotherapy regimen, age, and smoking status.

Conclusions

We found that Dmean, V10, and V20 correlated significantly with acute esophagitis. However, the chemotherapy regimen, age, and smoking status did not affect esophagitis development.

Oral extrusion of a vertebral body replacement device after chordoma tumor growth and radiation: case report and review

Background

Screw migration following anterior cervical discectomy and fusion is a very rare complication and it is often related to device failure. Even more exceptional is the extrusion of an intervertebral graft.

Case presentation

We report the second case of migration and extrusion through the oral cavity of a cervical vertebral body replacement device (expandable cylinder) in a patient that had undergone cervical corpectomy due to a vertebral chordoma.

Conclusion

The antecedent of radiation therapy as well as progressive tumor re-growth may have favored the development of this complication. A literature review is added.

Organs at risk radiation dose constraints

Dose constraints are essential for performing dosimetry, especially for intensity modulation and for radiotherapy under stereotaxic conditions. We present the update of the recommendations of the French society of oncological radiotherapy for the use of these doses in classical current practice but also for reirradiation.

Unrecognized digestive toxicities of radiation therapy

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

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.

Radio-induced esophageal motility disorders: An unrecognized diagnosis

PURPOSE

Esophageal motility disorders (EMD) after cervical or thoracic radiation therapy (RT) may represent a late impairment and appear under-diagnosed. This study aimed to assess the prevalence of EMD, diagnosed by high-resolution esophageal manometry (HREM) after cervical or thoracic RT. In this retrospective, single-centre study, all patients whom received cervical or thoracic RT and underwent HREM were eligible.

MATERIAL AND METHODS

Oncologic data were collected: site of neoplasia, type of cancer, oncologic management (surgery and chemotherapy). EMD were classified according to the new Chicago Classification.

RESULTS

Twenty patients (14 females), of mean age 62.33±11.14 years were included. Breast cancer was the most represented indication for RT (40%). Other cancers were lung tumor, head and neck tumors and Hogdkin's lymphoma. Dysphagia was the most frequent symptom justifying HREM (70%). Patients received a mean of 51±19.27 Gy, 70% of them (14/20) had radiation therapy concomitantly with chemotherapy. The delay between last radiation therapy session and HERM was 10.68±12.42 years. Twelve (60%) patients had an abnormal pattern at on HERM. Among them, 3 patients (15%) presented with a major motility disorder. The most frequent motility disorder was ineffective esophageal motility in 8 (40%) patients, 1 (5%) patient presented with type II achalasia.

CONCLUSION

EMD should be suspected in patients with a history of cervical or thoracic RT in case of upper GI symptoms with normal endoscopy. In these particular patients, a manometric diagnosis that can explain their symptoms is of particular importance to limit anxiety linked to unexplained troubles.

Death unrelated to cancer and death from aspiration pneumonia after definitive radiotherapy for head and neck cancer

BACKGROUND AND PURPOSE

The incidence of hypopharyngeal and supraglottic cancer (HSC) is high in Japan. This study aimed to retrospectively identify risk factors for death unrelated to cancer and death from aspiration pneumonia after definitive radiotherapy (RT) for HSC.

MATERIALS AND METHODS

Overall, 391 patients who began definitive RT for HSC between 2006 and 2014 were identified from the Osaka International Cancer Institute electronic database. Among 391 patients, 33 had a history of surgery for esophageal cancer (EC) and 19 received simultaneous RT for synchronous EC. The cause of death was divided into 3 main categories: "cancer under study," "other malignancy," and "unrelated to cancer." Cox proportional hazard model was used to estimate the hazard ratio (HR).

RESULTS

The median follow-up for survivors was 8 (range 3.6-14.1) years. At the last follow-up, 202 patients died. Death from "cancer under study," "other malignancy," and "unrelated to cancer" occurred in 92 (45.5%), 55 (27.2%), and 55 (27.2%) patients, respectively. Twelve patients died from aspiration pneumonia. In multivariate analysis for death unrelated to cancer and death from aspiration pneumonia, history of surgery for EC (HR: 3.87, p < 0.001; HR: 6.84, p = 0.007, respectively) and simultaneous RT for synchronous EC (HR: 3.74, p = 0.006; HR: 16.37, p < 0.001, respectively) were significant risk factors.

CONCLUSION

The laryngeal preservation approach by RT for HSC patients with a history of surgery for EC and simultaneous RT for synchronous EC should be used with caution.

Machine learning highlights the deficiency of conventional dosimetric constraints for prevention of high-grade radiation esophagitis in non-small cell lung cancer treated with chemoradiation

•

A large cohort to predict radiation esophagitis in lung cancer patients was used.

•

Modern machine learning models were implemented to predict radiation esophagitis.

•

Previously published predictors of grade ≥ 3 radiation esophagitis may be unreliable.

Background and Purpose

Radiation esophagitis is a clinically important toxicity seen with treatment for locally-advanced non-small cell lung cancer. There is considerable disagreement among prior studies in identifying predictors of radiation esophagitis. We apply machine learning algorithms to identify factors contributing to the development of radiation esophagitis to uncover previously unidentified criteria and more robust dosimetric factors.

Materials and Methods

We used machine learning approaches to identify predictors of grade ≥ 3 radiation esophagitis in a cohort of 202 consecutive locally-advanced non-small cell lung cancer patients treated with definitive chemoradiation from 2008 to 2016. We evaluated 35 clinical features per patient grouped into risk factors, comorbidities, imaging, stage, histology, radiotherapy, chemotherapy and dosimetry. Univariate and multivariate analyses were performed using a panel of 11 machine learning algorithms combined with predictive power assessments.

Results

All patients were treated to a median dose of 66.6 Gy at 1.8 Gy per fraction using photon (89.6%) and proton (10.4%) beam therapy, most often with concurrent chemotherapy (86.6%). 11.4% of patients developed grade ≥ 3 radiation esophagitis. On univariate analysis, no individual feature was found to predict radiation esophagitis (AUC range 0.45–0.55, p ≥ 0.07). In multivariate analysis, all machine learning algorithms exhibited poor predictive performance (AUC range 0.46–0.56, p ≥ 0.07).

Conclusions

Contemporary machine learning algorithms applied to our modern, relatively large institutional cohort could not identify any reliable predictors of grade ≥ 3 radiation esophagitis. Additional patients are needed, and novel patient-specific and treatment characteristics should be investigated to develop clinically meaningful methods to mitigate this survival altering toxicity.

Challenges of radical chemoradiation planning in Stage III non-small-cell lung cancer: Can volumetric modulated arc radiotherapy overcome an unfavourable location?

BACKGROUND AND PURPOSE

Radiotherapy treatment planning of radical doses for concurrent chemoradiation in Stage III non-small-cell lung cancer (NSCLC) presents many challenges. This dosimetric study aimed to analyse the impact of spatial location of tumour and nodal burden in limiting the achievement of normal organ constraints and the use of appropriate radiotherapy technique to address it.

MATERIALS AND METHODS

Fifteen Stage III NSCLC patients underwent 18F-fluorodeoxyglucose-positron emission tomography (FDG-PET)/computed tomography (CT) based treatment planning. VMAT (Volumetric Modulated Arc Radiotherapy) plans were made for all patients treated by 3D-CRT (3-Dimensional Conformal Radiotherapy). A binomial logistic regression was performed to ascertain the tumour and nodal characteristics that decreased the likelihood of being planned to 60 Gy.

RESULTS

Inability to achieve normal tissue constraints, particularly spinal cord dose to less than 50 Gy, during initial planning by the assigned treatment technique was the primary dose limiting factor in four patients (p = 0.02). Alternate VMAT plans could achieve the dose constraints where 3D-CRT was unsuccessful in patients with bulky central disease in two patients. This technique fell short when there was gross vertebral body erosion.

CONCLUSIONS

For tumours with bulky central disease, VMAT should be preferred. With gross vertebral body erosion, even VMAT falls short if the planning target volume includes the spinal cord. In a subset of Stage III NSCLC upfront chemoradiation to radical doses may not be feasible.

A new formalism of Dose Surface Histograms for robust modeling of skin toxicity in radiation therapy

PURPOSE

To present a new formalism for a robust computation of Dose-Surface Histograms (DSHs) to be exploited in the analysis of surface effects in radiation induced toxicity phenomena.

METHODS

A new formal recipe for the DSH extraction is described. It is based on the computation of the Dose-Volume Histogram (DVH) on a 3D structure in the limit of vanishing thickness to approach the two-dimensional organ manifold. The theory is customized for the application to skin description.

RESULTS

The derived formalism resulted in a redefinition of the generalized equivalent uniform dose (gEUD) and, accordingly, in an extension of the scope of the classical Lyman-Kutcher-Burman (LKB) Normal Tissue Complication Probability (NTCP) to a DSH-based toxicity modeling.

CONCLUSIONS

Our approach properly fits the intrinsic 3D nature of the DSH computation issue, and guarantees the rotational invariance and the robustness of the results. The proposed formalism can be easily implemented in treatment planning systems for dose optimization and potentially paves the way to a consistent analysis of radiation-induced morbidity endpoints related to surface effects in hollow organs.

Comparative Study of Esophageal Self-expandable Metallic Stent Insertion and Gastrostomy Feeding for Dysphagia Caused by Lung Cancer

Background/Aims

Dysphagia is encountered in a large proportion of patients with lung cancer and is associated with malnutrition and a poor quality of life. This study compared the clinical outcomes of self-expandable metallic stent (SEMS) insertion and percutaneous gastrostomy (PG) feeding for patients with lung cancer and dysphagia.

Methods

A total of 261 patients with lung cancer, who underwent either SEMS insertion (stent group) or PG (gastrostomy group) as an initial treatment procedure for dysphagia between July 1997 and July 2015 at the Samsung Medical Center, were reviewed retrospectively, and 84 patients with esophageal obstruction were identified. The clinical outcomes, including the overall survival, additional intervention, complications, and post-procedural nutritional status in the two groups, were compared.

Results

Among the 84 patients finally analyzed, 68 patients received SEMS insertion and 16 had PG. The stent group had less cervical obstruction and more mid-esophageal obstruction than the gastrostomy group. The Kaplan-Meier curves revealed similar overall survival in the two groups. Multivariate analysis showed that the two modalities had similar survival rates (PG compared with SEMS insertion, hazard ratio 0.682, p=0.219). Fifteen patients (22.1%) in the stent group received additional intervention, whereas there was no case in the gastrostomy group (p=0.063). The decrease in the serum albumin level after the procedure was lower in the gastrostomy group than in the stent group (-0.20±0.54 g/dL vs. -0.65±0.57 g/dL, p=0.013).

Conclusions

SEMS insertion and PG feeding for relieving dysphagia by lung cancer had a comparable survival outcome. On the other hand, PG was associated with a better nutritional status.

Clinical, dosimetric, and position factors for radiation-induced acute esophagitis in intensity-modulated (chemo)radiotherapy for locally advanced non-small-cell lung cancer

Purpose

The purpose of this study was to estimate the relation between acute esophagitis (AE) and clinical, dosimetric, and position factors in patients with locally advanced non-small-cell lung cancer (NSCLC) receiving intensity-modulated (chemo)radiotherapy.

Materials and methods

A retrospective cohort analysis was performed to identify factors associated with Common Toxicity Criteria for Adverse Events grade 2 or worse AE (AE2+). A multivariable model was established including patient- and treatment-related variables and esophageal dose–volume histogram parameters. The esophagus was divided according to physiological anatomy, and logistic regression was used to analyze the position parameter for its correlation with AE2+.

Results

The incidence of AE2+ was 27.5%. All models included gender, concurrent chemo-radiotherapy (CCRT), position parameter, and one of the dosimetric variables. The model with mean dose showed the best goodness of fit. Gender (OR=2.47, P=0.014), CCRT (OR=3.67, P=0.015), mean dose (OR=1.33, P<0.001), and maximum radiation position (OR=1.65, P=0.016) were significantly related to AE2+.

Conclusion

Gender, concurrent chemotherapy, maximum radiation position, and mean dose were independent risk factors for AE2+. The upper part of the esophagus showed a higher sensitivity to radiation toxicity.

Digestive toxicities after palliative three-dimensional conformal radiation therapy (3D-CRT) for cervico-thoracic spinal metastases

OBJECTIVE

The palliative treatment for cervico-thoracic spinal metastases is based on a three-dimensional conformal radiation therapy (3D-CRT). Digestive toxicities are common and cause a clinical impact frequently underestimated in patients. We performed a retrospective study of digestive side effects occurring after palliative 3D-CRT for cervico-thoracic spinal metastases.

PATIENTS AND METHODS

All patients receiving palliative 3D-CRT at Jean Bernard Center from January 2013 to December 2014 for spinal metastases between the 5th cervical vertebra (C5) and the 12th thoracic vertebra (T12) were eligible. Three-dimensional conformal RT was delivered by a linear accelerator (CLINAC, Varian). Premedication to prevent digestive toxicities was not used. Adverse events ("esophagitis" and "nausea and/or vomiting") were evaluated according to the NCI-CTCae (version 4).

RESULTS

From January 2013 to December 2014, 128 patients met the study criteria. The median age was 68.6 years [31.8; 88.6]. Most patients (84.4%) received 30 Gy in 10 fractions. The median overall time of treatment was 13 days [3-33]. Forty patients (31.3%) suffered from grade ≥ 2 of "esophagitis" (35 grade 2 (27.4%) and 5 grade 3 (3.9%)). Eight patients (6.3%) suffered from grade ≥ 2 of "nausea and/or vomiting" (6 grade 2 (4.7%), 1 grade 3 (0.8%), and 1 grade 4 (0.8%)).

CONCLUSION

The high incidence of moderate to severe digestive toxicities after palliative 3D-CRT for cervico-thoracic spinal metastases led to consider static or dynamic intensity-modulated radiation therapy (IMRT) to reduce the dose to organ at risk (the esophagus and stomach). Dosimetric studies and implementation in the clinic should be the next steps.

Prediction of Radiation Esophagitis in Non-Small Cell Lung Cancer Using Clinical Factors, Dosimetric Parameters, and Pretreatment Cytokine Levels

Radiation esophagitis (RE) is a common adverse event associated with radiotherapy for non-small cell lung cancer (NSCLC). While plasma cytokine levels have been correlated with other forms of radiation-induced toxicity, their association with RE has been less well studied. We analyzed data from 126 patients treated on 4 prospective clinical trials. Logistic regression models based on combinations of dosimetric factors [maximum dose to 2 cubic cm (D2cc) and generalized equivalent uniform dose (gEUD)], clinical variables, and pretreatment plasma levels of 30 cytokines were developed. Cross-validated estimates of area under the receiver operating characteristic curve (AUC) and log likelihood were used to assess prediction accuracy. Dose-only models predicted grade 3 RE with AUC values of 0.750 (D2cc) and 0.727 (gEUD). Combining clinical factors with D2cc increased the AUC to 0.779. Incorporating pretreatment cytokine measurements, modeled as direct associations with RE and as potential interactions with the dose-esophagitis association, produced AUC values of 0.758 and 0.773, respectively. D2cc and gEUD correlated with grade 3 RE with odds ratios (ORs) of 1.094/Gy and 1.096/Gy, respectively. Female gender was associated with a higher risk of RE, with ORs of 1.09 and 1.112 in the D2cc and gEUD models, respectively. Older age was associated with decreased risk of RE, with ORs of 0.992/year and 0.991/year in the D2cc and gEUD models, respectively. Combining clinical with dosimetric factors but not pretreatment cytokine levels yielded improved prediction of grade 3 RE compared to prediction by dose alone. Such multifactorial modeling may prove useful in directing radiation treatment planning.

A Phase II Toxicity End Point Trial (ICORG 99-09) of Accelerated Dose-escalated Hypofractionated Radiation in Non-small Cell Lung Cancer

AIMS

The objective of this phase II clinical trial was to prospectively evaluate the safety and efficacy of accelerated hypofractionated three-dimensional conformal radiation therapy (3DCRT) in localised non-resectable/non-operable non-small cell lung cancer (NSCLC).

MATERIALS AND METHODS

Sixty patients with stage I-III NSCLC were enrolled in a prospective single-arm All Ireland Co-operative Oncology Research Group (ICORG 99-09) toxicity end point phase II trial. The protocol allocated patients between three radiation schedule dose levels (60, 66 or 72 Gy, in 20, 22 and 24 fractions, respectively, 3 Gy daily, five fractions per week) according to combined lung V_25Gy (V_25Gy ≤ 30%) with built-in early stopping toxicity rules. The primary end point was toxicity with evaluation of dose-limiting toxicity. The secondary objectives included radiological tumour response rate at 3 months after the completion of radiation therapy and the thoracic progression-free survival time.

RESULTS

Sixty patients were recruited from August 1999 to June 2009. Forty-nine patients were included in the primary per-protocol analysis. Eleven patients were not evaluable. In the first 30 evaluable patient cohort, severe oesophageal toxicity was reported in two patients (2/49; 4% experiencing grade 5 oesophageal late toxicity, related to the 97% oesophageal length). The trial was temporarily closed and was then reopened to validate an oesophageal dose volume constraint (DVC) of limiting the length of oesophagus fully encompassed by the 97% isodose to less than 1 cm (applied to 21 patients). The trial prospectively showed the safety of the oesophageal DVC, with no oesophageal toxicity above grade 3 thereafter. Thirty-nine per cent of patients had disease progression at 3-4 months after radiotherapy, 22% had stable disease, 20% had a complete response and 14% had a partial response. The median overall survival was 13.6 months (95% confidence interval 10.5-16.7) and overall survival at 1 and 3 years was 57% and 29%, respectively.

CONCLUSION

A strategy using accelerated hypofractionated 3DCRT is feasible and reasonably safe for patients with inoperable NSCLC. It is safe to deliver for centrally located tumours if DVCs are applied to the oesophagus, which is the primary dose-limiting toxicity. Further studies are required to assess the efficacy of hypofractionated regimens for centrally located tumours using an oesophageal DVC and monitoring for oesophageal toxicity.

Acute and Late Toxicities of Concurrent Chemoradiotherapy for Locally-Advanced Non-Small Cell Lung Cancer

For patients with unresectable locally-advanced non-small cell lung cancer (LA-NSCLC), concurrent chemoradiotherapy improves overall survival as compared to sequential chemotherapy and radiation therapy, but is associated with higher rates of toxicities. Acute, clinically significant esophagitis or pneumonitis can occur in one in five patients. The risks of esophagitis and pneumonitis can impact the decision to deliver concurrent therapy and limit the total dose of radiation therapy that is delivered. Hematologic toxicities and emesis are common toxicities from systemic therapies for LA-NSCLC and can result in delaying chemotherapy dosing or chemotherapy dose reductions. Late treatment morbidities, including pulmonary fibrosis and cardiac toxicities, can also significantly impact quality of life and potentially even survival. Recent advances in radiation therapy treatment delivery, better knowledge of normal tissue radiotherapy tolerances and more widespread and improved uses of supportive care and medical management of systemic therapy toxicities have improved the therapeutic ratio and reduced the rates of chemoradiotherapy-induced toxicities. This review details the acute and late toxicities associated with definitive chemoradiotherapy for LA-NSCLC and discusses toxicity management and strategies to mitigate the risks of treatment-related toxicities.

Lycopene in the Prevention of Radiation-Induced Esophagitis

We aimed to research whether lycopene (L) could prevent radiation-induced acute esophageal toxicity in Wistar albino rats. 60 rats were placed in five groups as follows: control, L, radiotherapy (RT), L before RT (L + RT), and L before and after RT (L + RT + L). 6 mg/kg bw/day L was administered 7 days in the L group, 7 days before RT in the L + RT group, and 7 days before and after in the L + RT + L group. 35 Gy thoracic RT was performed. Serum L levels were measured, and the esophagi were evaluated histopathologically for intraepithelial degenerative changes-necrosis, vacuole formation, inflammation, regeneration-mitosis, and subepithelial bulla formation. L levels were significantly higher in the L receiving groups. All histopathologic results were significantly worse in the RT group than in the none-RT groups. The L + RT and the L + RT + L groups had better results than the RT group. Grade 2-3 degenerative changes-necrosis and vacuole formation were significantly lesser in the L + RT and the L + RT + L groups than those in the RT group. There was a trend toward decreased subepithelial bulla formation and inflammation in the L + RT and the L + RT + L groups compared to the RT group. Regeneration-mitosis was insignificantly lesser in the L + RT and significantly fewer in the L + RT + L groups than that in the RT group.

Independent test of a model to predict severe acute esophagitis

PURPOSE

Treatment planning factors are known to affect the risk of severe acute esophagitis during thoracic radiation therapy. We tested a previously published model to predict the risk of severe acute esophagitis on an independent data set.

METHODS AND MATERIALS

The data set consists of data from patients who had recoverable treatment plans and received definitive radiation therapy for non-small cell carcinoma of the lung at a single institution between November 2004 and January 2010. Complete esophagus dose-volume and available clinical information was extracted using our in-house software. The previously published model was a logistic function with a combination of mean esophageal dose and use of concurrent chemotherapy. In addition to testing the previous model, we used a novel, machine learning-based method to build a maximally predictive model.

RESULTS

Ninety-four patients (81.7%) developed Common Terminology Criteria for Adverse Events, Version 4, Grade 2 or more severe esophagitis (Grade 2: n = 79 and Grade 3: n = 15). Univariate analysis revealed that the most statistically significant dose-volume parameters included percentage of esophagus volume receiving ≥40 to 60 Gy, minimum dose to the highest 20% of esophagus volume (D20) to D35, and mean dose. Other significant predictors included concurrent chemotherapy and patient age. The previously published model predicted risk effectively with a Spearman's rank correlation coefficient (r_s) of 0.43 (P < .001) with good calibration (Hosmer-Lemeshow goodness of fit: P = .537). A new model that was built from the current data set found the same variables, yielding an r_s of 0.43 (P < .001) with a logistic function of 0.0853 × mean esophageal dose [Gy] + 1.49 × concurrent chemotherapy [1/0] - 1.75 and Hosmer-Lemeshow P = .659. A novel preconditioned least absolute shrinkage and selection operator method yielded an average r_s of 0.38 on 100 bootstrapped data sets.

CONCLUSIONS

The previously published model was validated on an independent data set and determined to be nearly as predictive as the best possible two-parameter logistic model even though it overpredicted risk systematically. A novel, machine learning-based model using a bootstrapping approach showed reasonable predictive power.

Radiation-induced esophagitis in lung cancer

Radiation-induced esophagitis is the most common local acute toxicity of radiotherapy (RT) delivered for the curative or palliative intent treatment of lung cancer. Although concurrent chemotherapy and higher RT dose are associated with increased esophagitis risk, advancements in RT techniques as well as adherence to esophageal dosimetric constraints may reduce the incidence and severity. Mild acute esophagitis symptoms are generally self-limited, and supportive management options include analgesics, acid suppression, diet modification, treatment for candidiasis, and maintenance of adequate nutrition. Esophageal stricture is the most common late sequela from esophageal irradiation and can be addressed with endoscopic dilatation. Approaches to prevent or mitigate these toxicities are also discussed.

Predictors for severe acute esophagitis in lung cancer patients treated with chemoradiotherapy: a systematic review

PURPOSE

To identify the risk factors for severe acute esophagitis (AE) in lung cancer patients undergoing chemoradiotherapy (CRT).

METHODS

Articles from PubMed, EMBASE, and the Cochrane Library were searched in August 2015. Articles reporting studies of the predictors for severe AE in lung cancer patients after CRT were included. Study quality was assessed using a modified quality assessment tool that was designed previously for an observational study. The effects of studies were combined with the study quality score using a best-evidence synthesis model. Severe AE incidence was also performed using the Metafor package of R-2.11.1.

RESULTS

A total of nine observational studies involving 1641 patients were included. The estimated incidence of severe AE was 14%. According to the best-evidence synthesis criteria, there were two strong-evidence risk factors for severe AE, which were the use of concurrent chemotherapy (CCT) and dose volume histogram (DVH). We also identified four limited-evidence risk factors.

CONCLUSIONS

More attention should be paid to the levels of patients' esophagus function. Although there is no conclusive evidence for severe AE in lung cancer patients after CRT, the above-mentioned factors provide evidence to guide clinicians as to which patients will have severe AE and to choose an optimal prophylactic strategy.

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

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

Accelerated hypofractionated three-dimensional conformal radiation therapy (3 Gy/fraction) combined with concurrent chemotherapy for patients with unresectable stage III non-small cell lung cancer: preliminary results of an early terminated phase II trial

BACKGROUND

Increasing the biological effective dose (BED) of radiotherapy for non-small cell lung cancer (NSCLC) can increase local control rates and improve overall survival. Compared with conventional fractionated radiotherapy, accelerated hypofractionated radiotherapy can yield higher BED, shorten the total treatment time, and theoretically obtain better efficacy. However, currently, there is no optimal hypofractionated radiotherapy regimen. Based on phase I trial results, we performed this phase II trial to further evaluate the safety and preliminary efficacy of accelerated hypofractionated three-dimensional conformal radiation therapy(3-DCRT) combined with concurrent chemotherapy for patients with unresectable stage III NSCLC.

METHODS

Patients with previously untreated unresectable stage III NSCLC received 3-DCRT with a total dose of 69 Gy, delivered at 3 Gy per fraction, once daily, five fractions per week, completed within 4.6 weeks. At the same time, platinum doublet chemotherapy was applied.

RESULTS

After 12 patients were enrolled in the group, the trial was terminated early. There were five cases of grade III radiation esophagitis, of which four cases completed the radiation doses of 51 Gy, 51 Gy, 54 Gy, and 66 Gy, and one case had 16 days of radiation interruption. The incidence of grade III acute esophagitis in patients receiving an irradiation dose per fraction ≥2.7 Gy on the esophagus was 83.3% (5/6). The incidence of symptomatic grade III radiation pneumonitis among the seven patients who completed 69 Gy according to the plan was 28.6% (2/7). The median local control (LC) and overall survival (OS) were not achieved; the 1-year LC rate was 59.3%, and the 1-year OS rate was 78.6%.

CONCLUSION

For unresectable stage III NSCLC, the accelerated hypofractionated radiotherapy with a total dose of 69 Gy (3 Gy/f) combined with concurrent chemotherapy might result in severe radiation esophagitis and pneumonitis to severely affect the completion of the radiotherapy. Therefore, we considered that this regimen was infeasible. During the hypofractionated radiotherapy with concurrent chemotherapy, the irradiation dose per fraction to esophagus should be lower than 2.7 Gy. Further studies should be performed using esophageal tolerance as a metric in dose escalation protocols.

TRIAL REGISTRATION

NCT02720614, the date of registration: March 23, 2016.

Nutrition support and dietary interventions for patients with lung cancer: current insights

Malnutrition and weight loss are prevalent in patients with lung cancer. The impact of malnutrition on patients with cancer, and specifically in patients with lung cancer, has been demonstrated in a large number of studies. Malnutrition has been shown to negatively affect treatment completion, survival, quality of life, physical function, and health care costs. Emerging evidence is providing some insight into which lung cancer patients are at higher nutritional risk. In lung cancer patients treated with radiotherapy, stage III or more disease, treatment with concurrent chemotherapy and the extent of radiotherapy delivered to the esophagus appear to confer a higher risk of weight loss during and post-treatment. Studies investigating nutrition interventions for lung cancer patients have examined intensive dietary counseling, supplementation with fish oils, and interdisciplinary models of nutrition and exercise interventions and show promise for improved outcomes from these interventions. However, further research utilizing these interventions in large clinical trials is required to definitively establish effective interventions in this patient group.

Dosimetric evaluation of the feasibility of stereotactic body radiotherapy for primary lung cancer with lobe-specific selective elective nodal irradiation

More than 10% of all patients treated with stereotactic body radiotherapy (SBRT) for primary lung cancer develop regional lymph node recurrence. We evaluated the dosimetric feasibility of SBRT with lobe-specific selective elective nodal irradiation (ENI) on dose-volume histograms. A total of 21 patients were treated with SBRT for Stage I primary lung cancer between January 2010 and June 2012 at our institution. The extents of lobe-specific selective ENI fields were determined with reference to prior surgical reports. The ENI fields included lymph node stations (LNS) 3 + 4 + 11 for the right upper lobe tumors, LNS 7 + 11 for the right middle or lower lobe tumors, LNS 5 + 11 for the left upper lobe tumors, and LNS 7 + 11 for the left lower lobe tumors. A composite plan was generated by combining the ENI plan and the SBRT plan and recalculating for biologically equivalent doses of 2 Gy per fraction, using a linear quadratic model. The V20 of the lung, D(1cm3) of the spinal cord, D(1cm3) and D(10cm3) of the esophagus and D(10cm3) of the tracheobronchial wall were evaluated. Of the 21 patients, nine patients (43%) could not fulfill the dose constraints. In all these patients, the distance between the planning target volume (PTV) of ENI (PTVeni) and the PTV of SBRT (PTVsrt) was ≤2.0 cm. Of the three patients who developed regional metastasis, two patients had isolated lymph node failure, and the lymph node metastasis was included within the ENI field. When the distance between the PTVeni and PTVsrt is >2.0 cm, SBRT with selective ENI may therefore dosimetrically feasible.

Radiation Effects in the Mediastinum and Surroundings: Imaging Findings and Complications

Radiotherapy is one of the cornerstones for treatment of patients with cancer. Although advances in radiotherapy technology have considerably improved radiation delivery, potential adverse effects are still common. Postradiation changes to the mediastinum can include different structures such as the heart, great vessels, and esophagus. The purpose of the article was to illustrate the expected variety of changes to the mediastinum and adjacent lung resulting from external beam radiotherapy and radiotherapy-induced complications to the mediastinum and to discuss different radiotherapy delivery techniques.

Multivariable normal-tissue complication modeling of acute esophageal toxicity in advanced stage non-small cell lung cancer patients treated with intensity-modulated (chemo-)radiotherapy

BACKGROUND AND PURPOSE

The majority of normal-tissue complication probability (NTCP) models for acute esophageal toxicity (AET) in advanced stage non-small cell lung cancer (AS-NSCLC) patients treated with (chemo-)radiotherapy are based on three-dimensional conformal radiotherapy (3D-CRT). Due to distinct dosimetric characteristics of intensity-modulated radiation therapy (IMRT), 3D-CRT based models need revision. We established a multivariable NTCP model for AET in 149 AS-NSCLC patients undergoing IMRT.

MATERIALS AND METHODS

An established model selection procedure was used to develop an NTCP model for Grade ⩾2 AET (53 patients) including clinical and esophageal dose-volume histogram parameters.

RESULTS

The NTCP model predicted an increased risk of Grade ⩾2 AET in case of: concurrent chemoradiotherapy (CCR) [adjusted odds ratio (OR) 14.08, 95% confidence interval (CI) 4.70-42.19; p<0.001], increasing mean esophageal dose [Dmean; OR 1.12 per Gy increase, 95% CI 1.06-1.19; p<0.001], female patients (OR 3.33, 95% CI 1.36-8.17; p=0.008), and ⩾cT3 (OR 2.7, 95% CI 1.12-6.50; p=0.026). The AUC was 0.82 and the model showed good calibration.

CONCLUSIONS

A multivariable NTCP model including CCR, Dmean, clinical tumor stage and gender predicts Grade ⩾2 AET after IMRT for AS-NSCLC. Prior to clinical introduction, the model needs validation in an independent patient cohort.

Focus on treatment complications and optimal management: radiation oncology

BACKGROUND

Esophagitis and pneumonitis are the most important treatment complications and dose-limiting toxicities in non-small cell lung cancer (NSCLC) patients treated with radiotherapy (RT) alone or combined modality therapy.

METHODS

A literature research was performed to identify published articles relating clinical and dosimetric parameters associated with significant radiation pneumonitis (RP) and esophagitis in NSCLC patients treated with three-dimensional conformal RT.

RESULTS

Possible clinical parameters associated with acute and or late esophagitis are concurrent chemoradiation, hyperfractionated and accelerated radiation regimens, dysphagia and neutropenia during treatment. Mean dose <34 Gy is currently used as standard dosimetric recommendation. Addition of chemotherapy and hyperfractionation are also associated with the risk of pneumonitis. Both the V20 and the mean lung dose are used as dosimetric parameter to correlate with the risk of high-grade radiation pneumonitis.

CONCLUSIONS

A variety of clinical and dosimetric parameters have been associated with acute and late toxicity. Treatment consist mainly in symptomatic relieve. Further research is necessary, as many studies led to different and sometimes even contradictory results.

Incidence and predictors of severe acute esophagitis and subsequent esophageal stricture in patients treated with accelerated hyperfractionated chemoradiation for limited-stage small cell lung cancer

PURPOSE

Clinical and dosimetric predictors of severe (grade 3 or greater) acute esophageal toxicity and subsequent esophageal dilation were explored in patients with limited-stage small cell lung cancer treated with accelerated hyperfractionated chemoradiation.

METHODS AND MATERIALS

A total of 130 patients were identified who were treated to 45 Gy in 1.5-Gy twice-daily fractions with concurrent platinum-based chemotherapy between 2000 and 2009. Data on clinical, disease-related, and treatment-related variables were collected. Patients with percutaneous endoscopic gastrostomy tube insertion or intravenous hydration because of poor oral intake were designated as having acute grade 3 esophagitis. Univariate and multivariate analyses that associated treatment characteristics with esophagitis were assessed via logistic regression, and optimal cut points were identified with recursive partitioning analysis.

RESULTS

Twenty-five patients developed severe acute esophagitis, at a rate of 26% (18/69) in patients treated with earlier 3-dimensional conformal radiation therapy techniques and 11.5% (7/61) in patients treated with intensity modulated radiation therapy techniques and omission of elective nodal irradiation. The incidence of esophageal stricture was 6% overall (8 of 128 eligible) but 26% (6/23) among those who experienced prior grade 3 acute esophagitis and 2% (2/105) among those with acute esophagitis less than or equal to grade 2. Significant multivariate predictors of acute esophagitis were mean dose and volume of esophagus receiving at least 5% to 35% of the prescribed dose (V5 to V40). Patients with V5 ≥ 74% had a 44.4% risk of severe acute esophagitis (12/27) versus 12.6% (13/103) among those with V5 < 74%. V45 was the only dosimetric predictor for esophageal stricture, with 13.7% of patients in whom V45 was ≥37.5% requiring subsequent dilation.

CONCLUSIONS

Modern radiation techniques are associated with a lower frequency of severe acute esophagitis than previous paradigms. The proportion of esophagus receiving low- to moderate-range doses (mean, V5 through V40) predicts acute esophagitis, whereas the proportion of esophagus that receives high doses (V45) predicts the development of esophageal stricture that requires dilation. Patients who develop grade 3 acute esophagitis are at significant risk for subsequent esophageal stricture, whereas those with acute esophagitis of grade 2 or less display minimal risk.

Treatment-related acute esophagitis for patients with locoregionally advanced non-small cell lung cancer treated with involved-field radiotherapy and concurrent chemotherapy

PURPOSE

To explore the incidence and risk factors for treatment-related acute esophagitis associated with involved-field radiation therapy (RT) delivered concurrently with chemotherapy for patients with locoregionally advanced non-small cell lung cancer.

MATERIALS AND METHODS

Forty-nine consecutive patients diagnosed with locoregionally advanced non-small cell lung cancer were treated using involved-field RT. Radiotherapy target volumes included the primary lung tumor and involved mediastinal lymphadenopathy as defined on imaging studies including computed tomography of the chest and fluorodeoxyglucose-positron emission tomography/computed tomography. The patients were treated to a median total dose of 63 Gy (range, 55.8 to 74 Gy) using daily fractions of 1.8 or 2.0 Gy. No elective radiotherapy of mediastinal lymph nodes was used. Concurrent platinum-based chemotherapy was delivered to all patients. Treatment-related toxicity was evaluated during the course of RT and subsequent follow-up visits.

RESULTS

Thirty-one (63%) patients were female and 18 (37%) were male. Median age at the time of diagnosis was 68 years (range, 36 to 83 y). Thirty-one patients (63%) developed treatment-related acute esophagitis: 24 patients (49%) grade 2 and 7 (14%) patients grade 3 esophagitis, with the peak occurring during the seventh week of radiotherapy. No grade ≥ 4 esophagitis was seen in this cohort. Eighteen patients (37%) did not develop radiation-induced esophagitis associated with their course of chemoradiotherapy. In the univariate analysis, age at the time of diagnosis, radiation dose per fraction, and total volume of the esophagus were significantly associated with the risk of acute esophagitis. Increasing age reduced the risk of acute esophagitis (odds ratio [OR] for 10-y increase = 0.40) as did increasing total esophagus volume (OR for 10-U increase = 0.27). Dose per fraction of 1.8 Gy was associated with lower risk of acute esophagitis when compared with dose per fraction of 2 Gy (OR = 0.19). Marginal associations were observed for all of the volume variables. Higher volume variable values had a nonsignificant association with an increase in risk of acute esophagitis. However, only the total volume of the esophagus (P = 0.0032) and larger dose per fraction (2 vs. 1.8 Gy) (P = 0.011) remained significantly associated with higher risk of developing grade ≥ 2 acute esophagitis in the multivariate analysis.

CONCLUSIONS

Higher risk of grade ≥ 2 treatment-related esophagitis was associated with lower total esophageal volume and higher radiotherapy dose per fraction and should be taken into consideration during patient treatment planning. Inclusion of total esophageal volume and dose per fraction into future clinical protocols may further help our understanding of treatment-related esophagitis and enable the development of novel preventative approaches.

Timing and intensity of changes in FDG uptake with symptomatic esophagitis during radiotherapy or chemo-radiotherapy

Purpose

To study whether esophageal FDG activity changes by time of mid-course of fractionated radiotherapy (RT), and whether these changes are associated with radiation esophagitis in patients with non-small cell lung cancer (NSCLC).

Methods

Fifty patients with stage I-III NSCLC were enrolled prospectively and, all received ≥60 Gy RT. FDG-PET/CT scans were acquired prior to, and during-RT after delivery of 45 Gy. Normalized standardized uptake values (NSUV), defined by the esophageal maximum SUV relative to intravascular background level in the aortic arch, were sampled in the esophagus at the level of the primary tumor, sternal notch, aortic arch, carina, and gastro-esophageal junction. Symptomatic radiation esophagitis was defined as an event.

Results

Compared to baseline, esophageal NSUV increased significantly during-RT at the level of the primary tumor (1.09 ± 0.05 vs.1.28 ± 0.06, p = 0.001), but did not change at other levels in the esophagus. 16 patients had radiation esophagitis events and these patients had significantly higher during-RT to baseline NSUV ratios than those without esophagitis (1.46 ± 0.12, 95% CI 1.20-1.71; vs. 1.11 ± 0.05, 95% CI 1.01-1.21, p = 0.002). Maximum esophageal dose (p = 0.029), concurrent chemotherapy (p = 0.022) and esophageal FDG PET NSUV ratio (during-RT to baseline, p = 0.007), were independent factors associated with esophagitis and area under curves (AUC) were 0.76, 0.70 and 0.78, respectively. Combining esophageal maximum dose and FDG PET NSUV Ratio at the tumor level increased AUC to 0.85 (p = 0.016).

Conclusion

FDG uptake increased in esophagus during-RT and this increase may predict radiation esphagitis during later course of treatment.

High-dose accelerated hypofractionated three-dimensional conformal radiotherapy (at 3 Gy/fraction) with concurrent vinorelbine and carboplatin chemotherapy in locally advanced non-small-cell lung cancer: a feasibility study

BACKGROUND

Increasing the radiotherapy dose can result in improved local control for non-small-cell lung cancer (NSCLC) and can thereby improve survival. Accelerated hypofractionated radiotherapy can expose tumors to a high dose of radiation in a short period of time, but the optimal treatment regimen remains unclear. The purpose of this study was to evaluate the feasibility of utilizing high-dose accelerated hypofractionated three-dimensional conformal radiotherapy (at 3 Gy/fraction) with concurrent vinorelbine (NVB) and carboplatin (CBP) chemotherapy for the treatment of local advanced NSCLC.

METHODS

Untreated patients with unresectable stage IIIA/IIIB NSCLC or patients with a recurrence of NSCLC received accelerated hypofractionated three-dimensional conformal radiotherapy. The total dose was greater than or equal to 60 Gy. The accelerated hypofractionated radiotherapy was conducted once daily at 3 Gy/fraction with 5 fractions per week, and the radiotherapy was completed in 5 weeks. In addition to radiotherapy, the patients also received at least 1 cycle of a concurrent two-drug chemotherapy regimen of NVB and CBP.

RESULTS

A total of 26 patients (19 previously untreated cases and 7 cases of recurrent disease) received 60Gy-75Gy radiotherapy with concurrent chemotherapy. All of the patients underwent evaluations for toxicity and preliminary therapeutic efficacy. There were no treatment-related deaths within the entire patient group. The major acute adverse reactions were radiation esophagitis (88.5%) and radiation pneumonitis (42.3%). The percentages of grade III acute radiation esophagitis and grade III radiation pneumonitis were 15.4% and 7.7%, respectively. Hematological toxicities were common and did not significantly affect the implementation of chemoradiotherapy after supportive treatment. Two patients received high dose of 75 Gy had grade III late esophageal toxicity, and none had grade IV and above. Grade III and above late lung toxicity did not occur.

CONCLUSION

High-dose accelerated hypofractionated three-dimensional conformal radiotherapy with a dose of 60 Gy or greater with concurrent NVB and CBP chemotherapy might be feasible. However esophagus toxicity needs special attention. A phase I trial is recommended to obtain the maximum tolerated radiation dose of accelerated hypofractionated radiotherapy with concurrent chemotherapy.

Analysis of esophageal-sparing treatment plans for patients with high-grade esophagitis

We retrospectively generated IMRT plans for 14 NSCLC patients who had experienced grade 2 or 3 esophagitis (CTCAE version 3.0). We generated 11-beam and reduced esophagus dose plan types to compare changes in the volume and length of esophagus receiving doses of 50, 55, 60, 65, and 70 Gy. Changes in planning target volume (PTV) dose coverage were also compared. If necessary, plans were renormalized to restore 95% PTV coverage. The critical organ doses examined were mean lung dose, mean heart dose, and volume of spinal cord receiving 50 Gy. The effect of interfractional motion was determined by applying a three-dimensional rigid shift to the dose grid. For the esophagus plan, the mean reduction in esophagus V50, V55, V60, V65, and V70 Gy was 2.8, 4.1, 5.9, 7.3, and 9.5 cm(3), respectively, compared with the clinical plan. The mean reductions in LE50, LE55, LE60, LE65, and LE70 Gy were 2.0, 3.0, 3.8, 4.0, and 4.6 cm, respectively. The mean heart and lung dose decreased 3.0 Gy and 2.4 Gy, respectively. The mean decreases in 90% and 95% PTV coverage were 1.7 Gy and 2.8 Gy, respectively. The normalized plans' mean reduction of esophagus V50, V55, V60, V65, and V70 Gy were 1.6, 2.0, 2.9, 3.9, and 5.5 cm(3), respectively, compared with the clinical plans. The normalized plans' mean reductions in LE50, LE55, LE60, LE65, and LE70 Gy were 4.9, 5.2, 5.4, 4.9, and 4.8 cm, respectively. The mean reduction in maximum esophagus dose with simulated interfractional motion was 3.0 Gy and 1.4 Gy for the clinical plan type and the esophagus plan type, respectively. In many cases, the esophagus dose can be greatly reduced while maintaining critical structure dose constraints. PTV coverage can be restored by increasing beam output, while still obtaining a dose reduction to the esophagus and maintaining dose constraints.

Dosimetric and clinical predictors of acute esophagitis in lung cancer patients in Turkey treated with radiotherapy

BACKGROUND

The purpose of this study was to determine the clinical and dosimetric factors associated with acute esophagitis (AE) in lung cancer patients treated with conformal radiotherapy (RT) in Turkey.

MATERIALS AND METHODS

In this retrospective review 104 lung cancer patients were examined. Esophagitis grades were verified weekly during treatment, and at 1 week, and 1 and 2 months afterwards. The clinical parameters included patient age, gender, tumor pathology, number of chemotherapy treatments before RT, concurrent chemotherapy, radiation dose, tumor response to RT, tumor localization, interruption of RT, weight loss, tumor and nodal stage and tumor volume. The following dosimetric parameters were analyzed for correlation of AE: The maximum (Dmax) and mean (Dmean) doses delivered to the esophagus, the percentage of esophagus volume receiving ≥10 Gy (V10), ≥20 Gy (V20), ≥30 Gy (V30), ≥35 Gy (V35), ≥40 Gy (V40), ≥45 Gy (V45), ≥50 Gy (V50) and ≥60 Gy (V60).

RESULTS

Fifty-five patients (52.9%) developed AE. Maximum grades of AE were recorded: Grade 1 in 51 patients (49%), and Grade 2 in 4 patients (3.8%). Clinical factors had no statistically significant influence on the incidence of AE. In terms of dosimetric findings, correlation analyses demonstrated a significant association between AE and Dmax (>5117 cGy), Dmean (>1487 cGy) and V10-60 (percentage of volume receiving >10 to 60 Gy). The most significant relationship between RT and esophagitis were in Dmax (>5117 cGy) (p=0.002) and percentage of esophageal volume receiving >30 Gy (V30>31%) (p=0.008) in the logistic regression analysis.

CONCLUSIONS

The maximum dose esophagus greater than 5117 cGy and approximately one third (31%) of the esophageal volume receiving >30 Gy was the most statistically significant predictive factor associated with esophagitis due to RT.

Esophagitis, treatment-related toxicity in non-small cell lung cancer

OBJECTIVES

Radiation esophagitis represents a significant complication experienced by non-small cell cancer (NSCLC) patients receiving thoracic irradiation. The objective of the current review was to assess the clinical and dosimetrical parameters that may predict radiation esophagitis.

METHODS

Studies were identified by searching PubMed electronic databases. Both prospective and retrospective studies were included. Information regarding clinical and dosimetrical parameters predicting for radiation-induced esophagitis was extracted and analyzed.

RESULTS

The esophageal clinical and dosimetric parameters that best predict acute esophagitis remain unclear. In many reports, Vx (the volume of esophagus receiving x Gy) stands out, with values of x ranging from 20-70 Gy. Other studies conclude that the maximal dose received by any point of the esophagus is the best predictor of esophagitis. Another metric implicated with esophageal toxicity in some reports is the proportion of the esophageal circumference or surface area that receives high doses of radiation.

CONCLUSIONS

Technological advancements in patient immobilization, setup verification, and radiotherapy delivery are increasingly being employed to limit the toxicity of thoracic irradiation. Future efforts are required to determine how these complex techniques should best be implemented to minimize the risks of acute and long-term esophageal injury.

Displaying 3D radiation dose on endoscopic video for therapeutic assessment and surgical guidance

We have developed a method to register and display 3D parametric data, in particular radiation dose, on two-dimensional endoscopic images. This registration of radiation dose to endoscopic or optical imaging may be valuable in assessment of normal tissue response to radiation, and visualization of radiated tissues in patients receiving post-radiation surgery. Electromagnetic sensors embedded in a flexible endoscope were used to track the position and orientation of the endoscope allowing registration of 2D endoscopic images to CT volumetric images and radiation doses planned with respect to these images. A surface was rendered from the CT image based on the air/tissue threshold, creating a virtual endoscopic view analogous to the real endoscopic view. Radiation dose at the surface or at known depth below the surface was assigned to each segment of the virtual surface. Dose could be displayed as either a colorwash on this surface or surface isodose lines. By assigning transparency levels to each surface segment based on dose or isoline location, the virtual dose display was overlaid onto the real endoscope image. Spatial accuracy of the dose display was tested using a cylindrical phantom with a treatment plan created for the phantom that matched dose levels with grid lines on the phantom surface. The accuracy of the dose display in these phantoms was 0.8-0.99 mm. To demonstrate clinical feasibility of this approach, the dose display was also tested on clinical data of a patient with laryngeal cancer treated with radiation therapy, with estimated display accuracy of ∼2-3 mm. The utility of the dose display for registration of radiation dose information to the surgical field was further demonstrated in a mock sarcoma case using a leg phantom. With direct overlay of radiation dose on endoscopic imaging, tissue toxicities and tumor response in endoluminal organs can be directly correlated with the actual tissue dose, offering a more nuanced assessment of normal tissue toxicities following radiation therapy and accurate registration of radiation dose to the surgical field.

[Esophageal toxicity of radiation therapy: clinical risk factors and management]

Acute radiation-induced esophagitis includes all clinical symptoms (odynophagia, dysphagia) occurring within 90 days after thoracic irradiation start. Its severity can be graded using RTOG and CTCAE scales. The clinical risk factors are: age, female gender, initial performance status, pre-therapeutic body mass index, pre-therapeutic dysphagia, tumoral and nodal stage, delivered dose, accelerated hyperfractionned radiotherapy, concomitant association of chemotherapy to radiotherapy and response to the treatment. The dosimetric parameters predictive of esophagitis are: mean dose, V(20Gy), V(30Gy), V(40Gy), V(45Gy) and V(50Gy). Amifostine is the only drug to have a proven radioprotective efficacy (evidence level C, ESMO recommendation grade III). The medical management of esophagitis associates a diet excluding irritant food, medication against gastroesophageal reflux, analgesic treatment according to the WHO scale and management of dehydration and denutrition by enteral feeding.

Dosimetric comparison of free-breathing and deep inspiration breath-hold radiotherapy for lung cancer

PURPOSE

The goal of this work was to evaluate the potential benefit of deep inspiration breath-hold (DIBH) compared to free breathing (FB) radiotherapy in a homogeneous population of patients with lung cancer.

METHODS AND MATERIALS

A total of 25 patients with non-small cell lung cancer treated by DIBH underwent an additional FB CT scan. The DIBH and FB treatment plans were compared. Target volume was compared using coverage, homogeneity, and conformal indices. Organs at risk were compared using V(5), V(13), V(20), V(25), V(37), mean dose (D(mean)) for lungs, V(40) and D(mean) for the heart, V(50), D(mean) and maximum dose (D(max)) for the esophagus, and using biological indices, i.e., the equivalent uniform dose (EUD) and the normal tissue complication probability (NTCP).

RESULTS

Median age was 62 years. Prescribed total dose was 66 Gy. Conformity index was improved with DIBH (0.67 vs. 0.58, p = 0.046) but coverage and homogeneity indices were not significantly different. Lung dosimetric parameters were improved using DIBH: D(mean) (13 vs. 15 Gy, p = 10(-4)), V(5) (43 vs. 51%, p = 6.10(-5)), V(13) (31 vs. 38%, p = 2.10(-3)), V(20) (25 vs. 31%, p = 0.01), V(25) (22% vs. 27%, p = 0.01) and V(37) (12 vs. 16%, p = 0.03), EUD (8.2 vs. 9.9 Gy, p = 3.10(-4)), and NTCP (1.9 vs. 4.8%, p = 10(-3)). For the heart, D(mean) (14 vs. 17 Gy, p = 0.003), V(40) (12 vs. 17%, p = 0.004), and EUD (19 vs. 22 Gy, p = 6.10(-4)) were reduced with DIBH, whereas V(30) and NTCP were similar. DIBH improved the D(mean) (28 vs. 30 Gy, p = 0.007) and V(50) (25 vs. 30%, p = 0.003) for the esophagus, while EUD, NTCP, and D(max) were not altered.

CONCLUSION

DIBH improves the target conformity index and heart and lung dosimetry in lung cancer patients treated with radiotherapy. The clinical implications of these findings should be confirmed.

Esophageal toxicity from high-dose, single-fraction paraspinal stereotactic radiosurgery

PURPOSE

To report the esophageal toxicity from single-fraction paraspinal stereotactic radiosurgery (SRS) and identify dosimetric and clinical risk factors for toxicity.

METHODS AND MATERIALS

A total of 204 spinal metastases abutting the esophagus (182 patients) were treated with high-dose single-fraction SRS during 2003-2010. Toxicity was scored using the National Cancer Institute Common Toxicity Criteria for Adverse Events, version 4.0. Dose-volume histograms were combined to generate a comprehensive atlas of complication incidence that identifies risk factors for toxicity. Correlation of dose-volume factors with esophageal toxicity was assessed using Fisher's exact test and logistic regression. Clinical factors were correlated with toxicity.

RESULTS

The median dose to the planning treatment volume was 24 Gy. Median follow-up was 12 months (range, 3-81). There were 31 (15%) acute and 24 (12%) late esophageal toxicities. The rate of grade ≥3 acute or late toxicity was 6.8% (14 patients). Fisher's exact test resulted in significant median splits for grade ≥3 toxicity at V12 = 3.78 cm(3) (relative risk [RR] 3.7, P=.05), V15 = 1.87 cm(3) (RR 13, P=.0013), V20 = 0.11 cm(3) (RR 6, P=0.01), and V22 = 0.0 cm(3) (RR 13, P=.0013). The median split for D2.5 cm(3) (14.02 Gy) was also a significant predictor of toxicity (RR 6; P=.01). A highly significant logistic regression model was generated on the basis of D2.5 cm(3). One hundred percent (n = 7) of grade ≥4 toxicities were associated with radiation recall reactions after doxorubicin or gemcitabine chemotherapy or iatrogenic manipulation of the irradiated esophagus.

CONCLUSIONS

High-dose, single-fraction paraspinal SRS has a low rate of grade ≥3 esophageal toxicity. Severe esophageal toxicity is minimized with careful attention to esophageal doses during treatment planning. Iatrogenic manipulation of the irradiated esophagus and systemic agents classically associated with radiation recall reactions are associated with development of grade ≥4 toxicity.