Dosimetric correlations of acute esophagitis in lung cancer patients treated with radiotherapy

Reduced frequency and severity of radiation esophagitis without marginal failure risk by contralateral esophagus sparing IMRT in stage III non-small cell lung cancer patients undergoing definitive concurrent chemoradiotherapy

PURPOSE

Radiation esophagitis is frequent and annoying toxicity in high dose thoracic radiation therapy. Contalateral esophagus sparing intensity modulated radiation therapy (CES-IMRT) has been proposed to mitigate this problem, and this is to report the impact of CES-IMRT in definitive concurrent chemoradiotherapy (dCCRT) for lung cancer patients.

MATERIALS AND METHODS

From January 2021 till May 2023, 183 stage III non-small cell lung cancer patients underwent dCCRT. Esophagus was located within 1 cm from internal target volume in 159 patients. We comparatively evaluated the frequency and severity of esophagitis by pain-killer usage, analgesic quantification algorithm (AQA) score, and failure patterns in 159 CES-necessary patients.

RESULTS

All patients underwent dCCRT (66 Gy in 30 fractions with concurrent chemotherapy). Actual CES-IMRT application was determined based on the discretion of responsible radiation oncologists: CES-applied in 41 patients; and CES-unapplied in 118. CES-applied patients experienced pain events less frequently (pain-killer usage: 53.7 % vs. 77.1 %, p = 0.008) and less severely (AQA score of 2-3: 39.0 % vs. 68.6 %, p = 0.002). On multivariate analyses, overlapping volume of esophagus and planning target (HR = 1.32, 95 % CI 1.12-1.55, p = 0.001) and CES-IMRT application (HR = 0.31, 95 % CI 0.13-0.76, p = 0.010) were associated with AQA score of 2-3 less frequently. There were no differences in failure pattern, progression-free survival, and overall survival.

CONCLUSIONS

CES-IMRT application resulted in less frequent and less severe pain events without compromising oncologic outcomes. Further studies, preferably in a randomized fashion, would be desired.

Model development of dose and volume predictors for esophagitis induced during chemoradiotherapy for lung cancer as a step towards radiobiological treatment planning

BACKGROUND

Currently, radiation therapy treatment planning system intends biological optimization that relies heavily upon plan metrics from tumor control probability (TCP) and normal tissue complication probability (NTCP) modeling. Implementation and expansion of TCP and NTCP models with alternative data is an important step towards reliable radiobiological treatment planning. In this retrospective single institution study, the treatment charts of 139 lung cancer patients treated with chemo-radiotherapy were reviewed and correlated dosimetric predictors with the incidence of esophagitis and established NTCP model of esophagitis grade 1 and 2 for lung cancer patients.

METHODS

Esophagus is an organ at risk (OAR) in lung cancer radiotherapy (RT). Esophagitis is a common toxicity induced by RT. In this study, dose volume parameters Vx (Vx: percentage esophageal volume receiving ≥ x Gy) and mean esophagus dose (MED) as quantitative dose-volume metrics, the esophagitis grade 1 and 2 as endpoints, were reviewed and derived from the treatment planning system and the electronic medical record system. Statistical analysis of binary logistic regression and probit were performed to have correlated the probability of grade 1 and 2 esophagitis to MED and Vx. IBM SPSS software version 24 at 5% significant level (α = 0.05) was used in the statistical analysis.

RESULTS

The probabilities of incidence of grade 1 and 2 esophagitis proportionally increased with increasing the values of Vx and MED. V20, V30, V40, V50 and MED are statistically significant good dosimetric predictors of esophagitis grade 1. 50% incidence probability (TD50) of MED for grade 1 and 2 esophagitis were determined. Lyman Kutcher Burman model parameters, such as, n, m and TD50, were fitted and compared with other published findings. Furthermore, the sigmoid shaped dose responding curve between probability of esophagitis grade 1 and MED were generated respecting to races, gender, age and smoking status.

CONCLUSIONS

V20, V30, V40 and V50 were added onto Quantitative Analysis of Normal Tissue Effects in the clinic, or QUANTEC group's dose constrains of V35, V50, V70 and MED. Our findings may be useful as both validation of 3-Dimensional planning era models and also additional clinical guidelines in treatment planning and plan evaluation using radiobiology optimization.

Comparison of dose volumetric parameters of oesophagus in the radiation treatment of carcinoma breast with and without oesophagus delineation

Aim:

There are only limited studies available in literature that discuss methods to reduce the oesophageal dose and acute oesophagitis during breast cancer radiotherapy. The aim of this study is to compare dose volumetric parameters of oesophagus in radiation treatment of breast with and without oesophagus delineation.

Methods:

Treatment plans of 44 patients, who underwent chest wall and supraclavicular fossa irradiation, were selected for the study. Oesophagus was later delineated and treatment replanned using three-dimensional conformal radiotherapy (3DCRT) considering oesophagus as an organ at risk (OAR). The dose prescribed was 40 Gy/15 fractions to the planning target volume (PTV). Dose volumetric parameters of oesophagus such as maximum dose (Dmax), mean dose (Dmean), the percentage of oesophagus volume receiving ≥15Gy (V15), ≥25Gy(V25), ≥33Gy(V33) and ipsilateral lung volume parameters V4, V8 and V16 were compared with already executed plans in which oesophagus was not delineated.

Results:

Contouring the oesophagus as an OAR as a part of the radiotherapy treatment for Carcinoma Breast resulted in statistically significant reduction in dose to the oesophagus. No statistically significant change was found in the ipsilateral lung volume parameters. No compromise in plan quality was required as evident from the statistically non-significant differences in Homogeneity index and Conformity index.

Findings:

3DCRT planning with oesophagus delineation can be considered as a method to reduce oesophageal dose and the acute oesophageal toxicity during radiotherapy for carcinoma breast.

The prognostic value of decrease in prognostic nutritional index in stage III non-small cell lung cancer patients during curative thoracic radiotherapy

BACKGROUND

Curative thoracic radiotherapy (CTRT) with concurrent chemotherapy has been considered as standard treatment approach for stage-III non-small cell lung cancer (NSCLC). The hematological and esophageal toxicities that have been encountered during CTRT would affect the immunonutritional status of the patients. The aim of this study is to evaluate the prognostic value of the change in pre- and post-treatment prognostic nutritional index (PNI) in stage-III NSCLC patients.

METHODS

Eighty seven consecutive stage III NSCLC patients' data were collected. Pre-radiotherapy (RT) and post-RT PNI values were calculated and the impact of prognostic value of PNI change on overall survival (OS) was evaluated by univariate and multivariate Cox regression analyses. A cutoff value of PNI change was obtained by receiver operator characteristic (ROC) curve analysis.

RESULTS

The cutoff value was found to be a 22% decrease in PNI by ROC curve analysis in terms of effect on OS. The median OS of low and high PNI decrease groups were 22.5 and 16.5 months respectively (P = 0,001). In univariate and multivariate analyses PNI decrease of ≥ 22% was found to be an independent poor prognostic factor for OS (P = 0.012) and hazard ratio (95% confidence interval)= 2.05 (1.16-3.62).

CONCLUSION

The PNI change would be a convenient parameter to assess the immunonutritional status of the patient at the end of CTRT. A decrease of more than 22% of PNI value may predict poor prognosis.

Radiation Esophagitis in a Patient with Oral Carcinoma and Bone Metastasis

Radiation esophagitis requiring endoscopic evaluation occurs quite rarely, affecting <1% of patients undergoing radiation treatment. Acute radiation esophagitis develops within 3 weeks of radiation therapy. We describe herein a case of radiation esophagitis in a patient with oral carcinoma with multiple general bone metastases. Cisplatin, fluorouracil, and cetuximab were given for 3 cycles. Radiation therapy (30 Gy) to the thoracic vertebrae and lumbar vertebrae was prescribed to prevent worsening of bone metastases and relieve pain. Neutropenia was also observed due to chemotherapy. After the end of radiation therapy, the patient experienced chest pain, heartburn, and dysphagia. Upper gastrointestinal endoscopy revealed severe radiation esophagitis of endoscopic Fukui Acute Radiation Esophagitis grade 4. Oral food was discontinued and an intravenous proton-pump inhibitor was administered. After 3 weeks, upper gastrointestinal endoscopy showed improvement of radiation esophagitis, with scars. The symptoms of chest pain, heartburn, and dysphagia had also disappeared. This is the first case to be reported of acute radiation esophagitis in a patient with oral carcinoma with bone metastasis who experienced dramatic improvement of endoscopic findings. Neutropenia appears to be associated with more severe acute radiation esophagitis.

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.

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.

Acute radiation oesophagitis associated with 2-deoxy-2-[18F]fluoro-d-glucose uptake on positron emission tomography/CT during chemo-radiation therapy in patients with non-small-cell lung cancer

INTRODUCTION

Acute radiation oesophagitis (ARO) is frequently experienced by patients receiving concurrent chemo-radiation therapy (cCRT) for non-small-cell lung cancer (NSCLC). We investigated ARO symptoms (CTCAE v3.0), radiation dose and oesophageal FDG PET/CT uptake.

METHOD

Candidates received cCRT (60 Gy, 2 Gy/fx) and sequential FDG PET/CT (baseline FDG₀ , FDG_wk2 and FDG_wk4 ). Mean and maximum standardized uptake value (SUVmean and SUVmax) and radiation dose (O_mean and O_max ) were calculated within the whole oesophagus and seven sub-regions (5-60 Gy).

RESULTS

Forty-four patients underwent FDG₀ and FDG_wk2 , and 41 (93%) received FDG_wk4 , resulting in 129 PET/CT scans for analysis. Of 29 (66%) patients with ≥ grade 2 ARO, SUVmax (mean ± SD) increased from FDG₀ to FDG_wk4 (3.06 ± 0.69 to 3.83 ± 1.27, P = 0.0019) and FDG_wk2 to FDG_wk4 (3.10 ± 0.75 to 3.83 ± 1.27, P = 0.0046). Radiation dose (mean ± SD) was higher in grade ≥2 patients; O_mean (47.5 ± 20 vs 53.9 ± 10.2, P = 0.0061), O_max (13.7 ± 9.6 vs 20.1 ± 10.6, P = 0.0009) and V40 Gy (8.0 ± 8.2 vs 11.9 ± 7.3, P = 0.0185).

CONCLUSIONS

FDG_wk4 SUVmax and radiation dose were associated with ≥ grade 2 ARO. Compared to subjective assessments, future interim FDG PET/CT acquired for disease response assessment may also be utilized to objectively characterize ARO severity and image-guided oesophageal dose constraints.

Potential for Interfraction Motion to Increase Esophageal Toxicity in Lung SBRT

Purpose:

To characterize the effect of the relative motion of esophagus and tumor on radiation doses to the esophagus in patients treated with stereotactic body radiation therapy for central lung tumors.

Methods and Materials:

Fifty fractions of stereotactic body radiation therapy in 10 patients with lung tumors within 2.5 cm of the esophagus were reviewed. The esophagus was delineated on each treatment’s cone-beam computed tomography scan and compared to its position on the planning scan. Dose–volume histograms were calculated using the original treatment beams to determine the actual dose delivered to the esophagus for each fraction of stereotactic body radiation therapy.

Results:

Median interfraction right–left shift of the esophagus was 0.9 mm (range, −5.4 to 3.3 mm) toward the left. Median interfraction anteroposterior shift was 0.7 mm (range, −3.7 to 11.5 mm) posteriorly. The median percentage increase in dose to 1 cm3, dose to 3.5 cm3, and dose to 5 cm³ was 1.7%, 5.6%, and 6.6%, respectively. Two cases of significant late esophageal toxicity were observed, with change in esophageal position relative to the planning target volume resulting in significantly higher D_5cc values than anticipated.

Conclusion:

Interfraction shifts between the internal target volume and esophagus can lead to unanticipated increases in the volume of esophagus receiving high doses when treating central lung tumors with stereotactic body radiation therapy. Certain practical steps, such as considering deep breath hold for internal target volume reduction, using a planning risk volume for esophagus, and carefully visualizing and considering esophageal position at the time of stereotactic body radiation therapy, can be taken to minimize unanticipated dose increases that could cause unexpected esophageal toxicity.

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.

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.

Association of oesophageal radiation dose volume metrics, neutropenia and acute radiation oesophagitis in patients receiving chemoradiotherapy for non-small cell lung cancer

INTRODUCTION

The relationship between oesophageal radiation dose volume metrics and dysphagia in patients having chemoradiation (CRT) for non-small cell lung cancer (NSCLC) is well established. There is also some evidence that neutropenia is a factor contributing to the severity of oesophagitis. We retrospectively analysed acute radiation oesophagitis (ARO) rates and severity in patients with NSCLC who received concurrent chemotherapy and high dose radiation therapy (CRT). We investigated if there was an association between grade of ARO, neutropenia and radiation dose volume metrics.

MATERIAL AND METHODS

Patients with NSCLC having concurrent CRT who had RT dose and toxicity data available were eligible. Exclusion criteria included previous thoracic RT, treatment interruptions and non-standard dose regimens. RT dosimetrics included maximum and mean oesophageal dose, oesophagus dose volume and length data.

RESULTS

Fifty four patients were eligible for analysis. 42 (78 %) patients received 60 Gy. Forty four (81 %) patients received carboplatin based chemotherapy. Forty eight (89 %) patients experienced ARO ≥ grade 1 (95 % CI: 78 % to 95 %). ARO grade was associated with mean dose (rs = 0.27, p = 0.049), V20 (rs = 0.31, p = 0.024) and whole oesophageal circumference receiving 20 Gy (rs = 0.32 p = 0.019). In patients who received these doses, V20 (n = 51, rs = 0.36, p = 0.011), V35 (n = 43, rs = 0.34, p = 0.027) and V60 (n = 25, rs = 0.59, P = 0.002) were associated with RO grade. Eleven of 25 (44 %) patients with ARO ≥ grade 2 also had ≥ grade 2 acute neutropenia compared with 5 of 29 (17 %) patients with RO grade 0 or 1 (p = 0.035).

CONCLUSION

In addition to oesophageal dose-volume metrics, neutropenia may also be a risk factor for higher grades of ARO.

Acute esophagitis for patients with local-regional advanced non small cell lung cancer treated with concurrent chemoradiotherapy

PURPOSE

Esophagitis is common in patients treated with definitive radiotherapy for local-regional advanced non small cell lung cancer (NSCLC). The purpose of this study was to estimate the dose-effect relationship using clinical and dosimetric parameters in patients receiving intensity modulated radiotherapy (IMRT) and concomitant chemotherapy (CCT).

METHODS

Between 2009 and 2013, 117 patients with stages IIB-IIIB NSCLC were treated in a multicenter randomized phase II trial with 2 cycles of induction chemotherapy followed by IMRT and CCT. The esophagitis was prospectively scored using the Common Toxicity Criteria 3.0. Clinical and dosimetric variables were analyzed for the correlation with grade ⩾2 esophagitis through logistic regression.

RESULTS

Grade 2 esophagitis was experienced by 31 (27%). All models including gender, institution, a dosimetric parameter and a position parameter were significantly associated with esophagitis. The two models using the relative esophagus volume irradiated above 40 Gy (V40, OR=2.18/10% volume) or the length of esophagus irradiated above 40 Gy (L40, OR=4.03/5 cm) were optimal. The upper part of esophagus was more sensitive and females experienced more toxicity than men.

CONCLUSION

V40 and L40 were most effective dosimetric predictors of grade ⩾2 esophagitis. The upper part of esophagus was more sensitive.

Normal tissue complication models for clinically relevant acute esophagitis (≥ grade 2) in patients treated with dose differentiated accelerated radiotherapy (DART-bid)

Background

One of the primary dose-limiting toxicities during thoracic irradiation is acute esophagitis (AE). The aim of this study is to investigate dosimetric and clinical predictors for AE grade ≥ 2 in patients treated with accelerated radiotherapy for locally advanced non-small cell lung cancer (NSCLC).

Patients and methods

66 NSCLC patients were included in the present analysis: 4 stage II, 44 stage IIIA and 18 stage IIIB. All patients received induction chemotherapy followed by dose differentiated accelerated radiotherapy (DART-bid). Depending on size (mean of three perpendicular diameters) tumors were binned in four dose groups: <2.5 cm 73.8 Gy, 2.5–4.5 cm 79.2 Gy, 4.5–6 cm 84.6 Gy, >6 cm 90 Gy. Patients were treated in 3D target splitting technique. In order to estimate the normal tissue complication probability (NTCP), two Lyman models and the cutoff-logistic regression model were fitted to the data with AE ≥ grade 2 as statistical endpoint. Inter-model comparison was performed with the corrected Akaike information criterion (AIC_c), which calculates the model’s quality of fit (likelihood value) in relation to its complexity (i.e. number of variables in the model) corrected by the number of patients in the dataset. Toxicity was documented prospectively according to RTOG.

Results

The median follow up was 686 days (range 84–2921 days), 23/66 patients (35 %) experienced AE ≥ grade 2. The actuarial local control rates were 72.6 % and 59.4 % at 2 and 3 years, regional control was 91 % at both time points. The Lyman-MED model (D50 = 32.8 Gy, m = 0.48) and the cutoff dose model (D_c = 38 Gy) provide the most efficient fit to the current dataset. On multivariate analysis V38 (volume of the esophagus that receives 38 Gy or above, 95 %-CI 28.2–57.3) was the most significant predictor of AE ≥ grade 2 (HR = 1.05, CI 1.01–1.09, p = 0.007).

Conclusion

Following high-dose accelerated radiotherapy the rate of AE ≥ grade 2 is slightly lower than reported for concomitant radio-chemotherapy with the additional benefit of markedly increased loco-regional tumor control. In the current patient cohort the most significant predictor of AE was found to be V38. A second clinically useful parameter in treatment planning may be MED (mean esophageal dose).

Electronic supplementary material

The online version of this article (doi:10.1186/s13014-015-0429-1) contains supplementary material, which is available to authorized users.

A prospective phase II trial of EGCG in treatment of acute radiation-induced esophagitis for stage III lung cancer

BACKGROUND

Acute radiation-induced esophagitis (ARIE) is one of main toxicities complicated by thoracic radiotherapy, influencing patients' quality of life and radiotherapy proceeding seriously. It is difficult to be cured rapidly so far. Our phase I trial preliminarily showed that EGCG may be a promising strategy in the treatment of ARIE.

MATERIALS AND METHODS

We prospectively enrolled patients with stage III lung cancer from the Shandong Tumor Hospital & Institute in China from January 2013 to September 2014. All patients received concurrent or sequential chemo-radiotherapy, or radiotherapy only. EGCG was administrated once ARIE appeared. EGCG was given with the concentration of 440μmol/L during radiotherapy and additionally two weeks after radiotherapy. RTOG score, dysphagia and pain related to esophagitis were recorded every week.

RESULTS

Thirty-seven patients with stage IIIA and IIIB lung cancer were enrolled in this trial. In comparison to the original, the RTOG score in the 1st, 2nd, 3rd, 4th, 5th week after EGCG prescription and the 1st, 2nd week after radiotherapy decreased significantly (P=0.002, 0.000, 0.000, 0.001, 0.102, 0.000, 0.000, respectively). The pain score of each week was significantly lower than the baseline (P=0.000, 0.000, 0.000, 0.000, 0.006, 0.000, 0.000, respectively).

CONCLUSION

This trial confirmed that the oral administration of EGCG is an effective and safe method to deal with ARIE. A phase III randomized controlled trial is expected to further corroborate the consequence of EGCG in ARIE treatment.

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.

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.

Acute radiation esophagitis caused by high-dose involved field radiotherapy with concurrent cisplatin and vinorelbine for stage III non-small cell lung cancer

Purpose of this study is to obtain dose-volume histogram (DVH) predictors and threshold values for radiation esophagitis caused by high-dose involved field radiotherapy (IFRT) with concurrent chemotherapy in patients with stage III non-small cell lung cancer (NSCLC). Thirty-two patients treated by 66 Gy/33 Fr, 72 Gy/36 Fr, and 78 Gy/39 Fr thoracic radiotherapy without elective nodal irradiation plus concurrent cisplatin and vinorelvine were reviewed. Acute radiation esophagitis was evaluated according to common terminology criteria for adverse events version 4.0, and correlations between grade 2 or worse radiation esophagitis and DVH parameters were investigated. Grade 0-1, 2, 3, and 4-5 of radiation esophagitis were seen in 11 (34.4%), 20 (62.5%), 1 (3.1%), and 0 (0%) of the patients, respectively. Multivariate analysis revealed that whole esophagus V35 is a predictor of radiation esophagitis (OR = 0.74 [95%CI; 0.60-0.91], p = 0.006). There is a significant difference (38.4% vs. 89.4%, p = 0.027) in the cumulative rates of acute esophagitis according to V35 values of more than 20% versus less. As compared with other factors concerning patient and tumor and treatment factors, V35 ≤ 20% of the esophagus was an independent predictor (HR 5 0.29 [95%CI; 0.09-0.85], p 5 0.025). In conclusion, whole esophagus V35 < 20% is proposed in high-dose IFRT with concurrent chemotherapy for stage III NSCLC patients.

Mean esophageal radiation dose is predictive of the grade of acute esophagitis in lung cancer patients treated with concurrent radiotherapy and chemotherapy

The intention of this research was to define the predictive factors for acute esophagitis (AE) in lung cancer patients treated with concurrent chemotherapy and three-dimensional conformal radiotherapy. The data for 72 lung cancer patients treated with concurrent chemoradiotherapy between 2008 and 2010 were prospectively evaluated. Mean lung dose, mean dose of esophagus, volume of esophagus irradiated and percentage of esophagus volume treated were analysed according to esophagitis grades. The mean esophageal dose was associated with an increased risk of esophageal toxicity (Kruskal-Wallis test, P < 0.001). However, the mean lung dose and the volume of esophagus irradiated were not associated with an increased risk of esophageal toxicity (Kruskal-Wallis test, P = 0.50 and P = 0.41, respectively). The mean radiation dose received by the esophagus was found to be highly correlated with the duration of Grade 2 esophagitis (Spearman test, r = 0.82, P < 0.001). The mean dose of esophagus ≥28 Gy showed statistical significance with respect to AE Grade 2 or worse (receiver operating characteristic curve analysis, 95% CI, 0.929-1.014). In conclusion, the mean esophageal dose was significantly associated with a risk of esophageal toxicity in patients with lung cancer treated with concurrent radiotherapy and chemotherapy.

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.

[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.

Correlation of dosimetric parameters obtained with the analytical anisotropic algorithm and toxicity of chest chemoradiation in lung carcinoma

The purpose of this study was to analyze and revisit toxicity related to chest chemoradiotherapy and to correlate these side effects with dosimetric parameters obtained using analytical anisotropic algorithm (AAA) in locally unresectable advanced lung cancer. We retrospectively analyzed data from 47 lung cancer patients between 2005 and 2008. All received conformal 3D radiotherapy using high-energy linear accelerator plus concomitant chemotherapy. All treatment planning data were transferred into Eclipse 8.05 (Varian Medical Systems, Palo Alto, CA) and dosimetric calculations were performed using AAA. Thirty-three patients (70.2%) developed acute pneumopathy after radiotherapy (grades 1 and 2). One patient (2.1%) presented with grade 3 pneumopathy. Thirty-one (66%) presented with grades 1-2 lung fibrosis, and 1 patient presented with grade 3 lung fibrosis. Thirty-four patients (72.3%) developed grade 1-2 acute oesophagic toxicity. Four patients (8.5%) presented with grades 3 and 4 dysphagia, necessitating prolonged parenteral nutrition. Median prescribed dose was 64 Gy (range 50-74) with conventional fractionation (2 Gy per fraction). Dose-volume constraints were respected with a median V20 of 23.5% (maximum 34%) and a median V30 of 17% (maximum 25%). The median dose delivered to healthy contralateral lung was 13.1 Gy (maximum 18.1 Gy). At univariate analysis, larger planning target volume and V20 were significantly associated with the probability of grade ≥2 radiation-induced pneumopathy (p = 0.022 and p = 0.017, respectively). No relation between oesophagic toxicity and clinical/dosimetric parameters could be established. Using AAA, the present results confirm the predictive value of the V20 for lung toxicity as already demonstrated with the conventional pencil beam convolution approach.

Modeling the risk of radiation-induced acute esophagitis for combined Washington University and RTOG trial 93-11 lung cancer patients

PURPOSE

To construct a maximally predictive model of the risk of severe acute esophagitis (AE) for patients who receive definitive radiation therapy (RT) for non-small-cell lung cancer.

METHODS AND MATERIALS

The dataset includes Washington University and RTOG 93-11 clinical trial data (events/patients: 120/374, WUSTL = 101/237, RTOG9311 = 19/137). Statistical model building was performed based on dosimetric and clinical parameters (patient age, sex, weight loss, pretreatment chemotherapy, concurrent chemotherapy, fraction size). A wide range of dose-volume parameters were extracted from dearchived treatment plans, including Dx, Vx, MOHx (mean of hottest x% volume), MOCx (mean of coldest x% volume), and gEUD (generalized equivalent uniform dose) values.

RESULTS

The most significant single parameters for predicting acute esophagitis (RTOG Grade 2 or greater) were MOH85, mean esophagus dose (MED), and V30. A superior-inferior weighted dose-center position was derived but not found to be significant. Fraction size was found to be significant on univariate logistic analysis (Spearman R = 0.421, p < 0.00001) but not multivariate logistic modeling. Cross-validation model building was used to determine that an optimal model size needed only two parameters (MOH85 and concurrent chemotherapy, robustly selected on bootstrap model-rebuilding). Mean esophagus dose (MED) is preferred instead of MOH85, as it gives nearly the same statistical performance and is easier to compute. AE risk is given as a logistic function of (0.0688 MED+1.50 ConChemo-3.13), where MED is in Gy and ConChemo is either 1 (yes) if concurrent chemotherapy was given, or 0 (no). This model correlates to the observed risk of AE with a Spearman coefficient of 0.629 (p < 0.000001).

CONCLUSIONS

Multivariate statistical model building with cross-validation suggests that a two-variable logistic model based on mean dose and the use of concurrent chemotherapy robustly predicts acute esophagitis risk in combined-data WUSTL and RTOG 93-11 trial datasets.

Clinical and dosimetric risk factors of acute esophagitis in patients treated with 3-dimensional conformal radiotherapy for non-small-cell lung cancer

PURPOSE

To analyze the clinical and dosimetric risk factors of acute esophagitis (AE) in non-small-cell lung cancer (NSCLC) patients treated with 3-dimensional conformal radiotherapy (3D-CRT).

METHODS AND MATERIALS

One hundred two NSCLC patients treated with 3D-CRT were retrospectively analyzed. Forty of these 102 patients analyzed were treated with concurrent chemotherapy (CCT). The median biologic effective dose of radiotherapy was 72.0 Gy. AE was scored according to the Radiation Therapy Oncology Group criteria. The clinical and dosimetric factors associated with grade 2 or worse AE were analyzed using univariate and multivariate binary logistic analysis.

RESULTS

There were no grade 4 or 5 AE observed in the 102 patients analyzed. Thirty-four of 102 patients (33.3%) developed grade 2 or 3 AE. Univariate analysis showed that clinical factors, such as lymph nodes stage (N 0/1 vs. N 2/3), pretreatment weight loss > or =5%, CCT, and the use of late-course hyperfractionated radiotherapy were significantly associated with grade 2 and 3 AE. Dose volume parameters of esophagus including mean esophageal dose, maximal esophageal dose, rV15, rV20, rV25, rV30, rV35, rV40, rV45, rV50, rV55, rV60 were also associated with AE. On multivariate forward step-wise logistic analysis, CCT, lymph nodes stage, and rV55 emerged as the statistically most significant factors of AE with OR parameters of 8.911, 4.832, and 1.083, respectively.

CONCLUSION

CCT, lymphatic status, and rV55 were strong predictors of grade 2 or worse AE in NSCLC treated with 3D-CRT.

Spanish radiobiological pattern of care in lung cancer: a GOECP/SEOR study

INTRODUCTION

A survey regarding radiobiological questions in the treatment of lung cancer (LC) was done to study the clinical aspects of radiotherapy in Spain, in order to standardise treatment decisions.

METHODS AND MATERIALS

From November 2007 to March 2008, a survey was performed among radiation oncologists in Spain specialising in LC treatment via e-mail, which included questions regarding different radiobiological aspects of radiotherapy LC treatment. The extent of the resulting material made it necessary to divide it into two parts; the first is presented in this article. The second, which includes items about alpha/beta-NTCP/TCP values and reirradiation criteria, will be reported elsewhere.

RESULTS

Thirty-one radiation therapists from 29 radiation oncology departments answered the survey. 77.4-93.5% of responders used the basic formula from the linear-quadratic model and/or computer software for radiobiological calculations; 100% used lung (mostly V20, median <30%) and spinal cord constraints (mostly a median of physical maximum dose <45.5 Gy); and 90.3% used heart and oesophagus constraints (very heterogeneous parameters in both organs).

CONCLUSIONS

Radiobiological considerations are clearly present in the planning process of radiotherapy of LC in Spain, with a high coincidence with the literature regarding lung and spinal cord constraints. The heterogeneity shown for oesophagus and heart results demonstrates the need for continuing investigation into the standardisation of clinical, dosimetric and radiobiologic aspects of the treatment of this cancer.

Radiation dose-volume effects in the esophagus

Publications relating esophageal radiation toxicity to clinical variables and to quantitative dose and dose-volume measures derived from three-dimensional conformal radiotherapy for non-small-cell lung cancer are reviewed. A variety of clinical and dosimetric parameters have been associated with acute and late toxicity. Suggestions for future studies are presented.

Radiation therapy in the elderly: more side effects and complications?

Aging is associated with physiological changes and comorbid illnesses, which may affect an individual's tolerance to radiation. There is the belief that a relationship exists between age and radiation toxicity and therefore non-curative schemes are offered to older patients. Preclinical studies show that normal tissue radiation-induced toxicity differs little with age. In the clinical setting, retrospective and some prospective studies have reported that elderly patients treated with radical radiotherapy alone or in combination with chemotherapy, who do not have comorbidities and retain a good performance status, show a benefit in treatment outcomes. However, an increase in acute effects or a lowered functional tolerance has also been reported. To select candidates for radical treatments, a specific geriatric assessment should be used to stratify elderly patients as a function of the physiological status. Only specifically designed prospective studies can define the role of radiation treatment in elderly patients with different physiological status.

Systematic review of dose-volume parameters in the prediction of esophagitis in thoracic radiotherapy

PURPOSE

With dose escalation and increasing use of concurrent chemoradiotherapy, radiation esophagitis (RE) remains a common treatment-limiting acute side effect in the treatment of thoracic malignancies. The advent of 3DCT planning has enabled investigators to study esophageal dose-volume histogram (DVH) parameters as predictors of RE. The purpose of this study was to assess published dosimetric parameters and toxicity data systematically in order to define reproducible predictors of RE, both for potential clinical use, and to provide recommendations for future research in the field.

MATERIALS AND METHODS

We performed a systematic literature review of published studies addressing RE in the treatment of lung cancer and thymoma. Our search strategy included a variety of electronic medical databases, textbooks and bibliographies. Both prospective and retrospective clinical studies were included. Information relating to the relationship among measured dosimetric parameters, patient demographics, tumor characteristics, chemotherapy and RE was extracted and analyzed.

RESULTS

Eighteen published studies were suitable for analysis. Eleven of these assessed acute RE, while the remainder assessed both acute and chronic RE together. Heterogeneity of esophageal contouring practices, individual differences in information reporting and variability of RE outcome definitions were assessed. Well-described clinical and logistic modeling directly related V(35Gy), V(60Gy) and SA(55Gy) to clinically significant RE.

CONCLUSIONS

Several reproducible dosimetric parameters exist in the literature, and these may be potentially relevant in the prediction of RE in the radiotherapy of thoracic malignancies. Further clarification of the predictive relationship between such standardized dosimetric parameters and observed RE outcomes is essential to develop efficient radiation treatment planning in locally advanced NSCLC in the modern concurrent chemotherapy and image-guided IMRT era.

Predictors of acute esophagitis in lung cancer patients treated with concurrent three-dimensional conformal radiotherapy and chemotherapy

PURPOSE

To evaluate the risk factors for acute esophagitis (AET) in lung cancer patients treated with concurrent 3D-CRT and chemotherapy.

METHODS AND MATERIALS

Data from 100 patients treated with concurrent chemoradiotherapy with a mean dose of 62.05 +/- 4.64 Gy were prospectively evaluated. Esophageal toxicity was graded according to criteria of the Radiation Therapy Oncology Group. The following dosimetric parameters were analyzed: length and volume of esophagus in treatment field, percentage of esophagus volume treated to >or=10, >or=20, >or=30, >or=35, >or=40, >or=45, >or=50, >or=55, and >or=60 Gy, and the maximum (D(max)) and mean doses (D(mean)) delivered to the esophagus. Also, we developed an esophagitis index (EI) to account the esophagitis grades over treatment time.

RESULTS

A total of 59 patients developed AET (Grade 1, 26 patients; Grade 2, 29 patients; and Grade 3, 4 patients). V50 was associated with AET duration (p = 0.017), AET Grade 1 duration (p = 0.016), maximum analgesia (p = 0.019), esophagitis index score (p = 0.024), and AET Grade >or=1 (p = 0.058). If V50 is <30% there is a 47.3% risk of AET Grade >or=1, which increases to 73.3% if V50 is >or=30% (p = 0.008). The predictive abilities of models (sensitivity and specificity) were calculated by receiver operating characeristic curves.

CONCLUSIONS

According to the receiver operating characeristic curve analysis, the 30% of esophageal volume receiving >or=50 Gy was the most statistically significant factor associated with AET Grade >or=1 and maximum analgesia (A(max)). There was an association with AET Grade >or=2 but it did not achieve statistical significance (p = 0.076).

Accelerated high-dose radiotherapy alone or combined with either concomitant or sequential chemotherapy; treatments of choice in patients with Non-Small Cell Lung Cancer

BACKGROUND

Results of high-dose chemo-radiotherapy (CRT), using the treatment schedules of EORTC study 08972/22973 or radiotherapy (RT) alone were analyzed among all patients (pts) with Non Small Cell Lung Cancer (NSCLC) treated with curative intent in our department from 1995-2004.

MATERIAL

Included are 131 pts with medically inoperable or with irresectable NSCLC (TNM stage I:15 pts, IIB:15 pts, IIIA:57 pts, IIIB:43 pts, X:1 pt).

TREATMENT

Group I: Concomitant CRT: 66 Gy/2.75 Gy/24 fractions (fx)/33 days combined with daily administration of cisplatin 6 mg/m(2): 56 pts (standard).Group II: Sequential CRT: two courses of a 21-day schedule of chemotherapy (gemcitabin 1250 mg/m(2) d1, cisplatin 75 mg/m2 d2) followed by 66 Gy/2.75 Gy/24 fx/33 days without daily cisplatin: 26 pts.Group III: RT: 66 Gy/2.75 Gy/24 fx/33 days or 60 Gy/3 Gy/20 fx/26 days: 49 pts.

RESULTS

The 1, 2, and 5 year actuarial overall survival (OS) were 46%, 24%, and 15%, respectively.At multivariate analysis the only factor with a significantly positive influence on OS was treatment with chemo-radiation (P = 0.024) (1-, 2-, and 5-yr OS 56%, 30% and 22% respectively). The incidence of local recurrence was 36%, the incidence of distant metastases 46%.Late complications grade 3 were seen in 21 pts and grade 4 in 4 patients. One patient had a lethal complication (oesophageal). For 32 patients insufficient data were available to assess late complications.

CONCLUSION

In this study we were able to reproduce the results of EORTC trial 08972/22973 in a non-selected patient population outside of the setting of a randomised trial. Radiotherapy (66 Gy/24 fx/33 days) combined with either concomitant daily low dose cisplatin or with two neo-adjuvant courses of gemcitabin and cisplatin are effective treatments for patients with locally advanced Non-Small Cell Lung Cancer. The concomitant schedule is also suitable for elderly people with co-morbidity.

An analysis of 6-MV versus 18-MV photon energy plans for intensity-modulated radiation therapy (IMRT) of lung cancer

PURPOSE

To analyse the supposed benefits of low over high photon energies for the radiotherapy of lung cancer.

MATERIALS AND METHODS

For 13 patients, 6- and 18-MV IMRT planning was performed using identical planning objectives and dose constraints. Plans were compared according to dose-volume histogram (DVH) analysis including conformity and homogeneity indices (CI and HI) and overall plan quality (composite score CS), considering also magnitude and location of planning target volumes (PTVs).

RESULTS

With 6-MV plans, CSs were better in 11/13, HIs in 10/13 and CIs in 6/13 patients compared with 18-MV plans. Six-MV plans resulted in a better normal tissue sparing except for specified dose levels to the thorax and spinal cord. On average differences between 6 and 18 MV both for the PTV and normal tissues were not statistically significant (p>0.05). Considering size and location of the PTVs as well as their relative position to normal tissue, overall no significant differences between 6 and 18 MV were observed.

CONCLUSIONS

On average no clinically or statistically significant differences between 6- and 18-MV plans were observed. High photon energies should therefore not be excluded a priori when a dose-calculation algorithm is utilized that accurately accounts for heterogeneities.

Complications aiguës et tardives des irradiations thoraciques

Radiotherapy of lung cancer is often complexe because of several organs at risk such as lung, heart, esophagus or spinal cord. An accurate balance needs to be defined between the necessities to reach a local control and to limit the risks of toxicities for each of them. Several parameters were significantly correlated with radiation induced lung toxicities (V13, V20, 30, Mean Dose) and esophagitis (V40 to V60). However no parameters are clearly defined for heart toxicities. The large number of parameters described for lung and esophagus highlights the necessity to perform an overall analysis of the DVHs that could be possible by using Nomal Tissue Complication Probability models.

Predictive factors for acute esophageal toxicity in thoracic radiotherapy

Acute esophageal toxicity (AET) is a common complication and dose-limiting toxicity in thoracic radiotherapy. Previous studies demonstrated several clinical and dosimetric parameters of AET in patients with lung cancer. However, there are few reports dealing with these variables in intra-thoracic malignancies, including lung cancer and other thoracic malignancy. The purpose of this study was to evaluate the clinical and dosimetric factors associated with AET in patients with intra-thoracic malignancies. We examined 61 patients with intra-thoracic malignancies treated with radiotherapy: 34 patients with non-small-cell lung cancer (55%), 9 cases with small-cell lung cancer (15%), 7 cases with thymic cancer (11%), 4 thymomas (7%), 2 malignant lymphomas (3%), one seminoma (2%), one liposarcoma (2%), and 3 cases of other malignancies (5%). Radiotherapy was performed with a median dose of 60 Gray (Gy) (range 40-67 Gy). AET was graded according to the Radiation Therapy Oncology Group (RTOG) criteria. The following parameters were analyzed with respect to associations with AET by univariate and multivariate analyses: age, gender, thoracic surgery before radiotherapy, concurrent chemotherapy, duration of radiotherapy, maximum esophageal dose, mean esophageal dose, and percentage of esophageal volume receiving from 10 Gy (V10) to 65 Gy (V65), in 5-Gy increments. 43 patients (70%) developed AET: 36 patients (59%) with AET of RTOG Grade 1, 7 patients (11%) with Grade 2, and no patients (0%) with Grade 3 or worse. On multivariate analysis, V35 > 30% was the most statistically significant factor associated with mild AET (p = 0.013). Our findings provide a better understanding of the factors related to AET, and might be useful in designing a treatment plan to prevent severe esophageal toxicity.