Outcomes research in cancer clinical trial cooperative groups: the RTOG model

Symptom science research conducted in community programs funded by the US National Cancer Institute: a 12-year review, 2008 to 2019

PURPOSE

This study was conducted to describe the portfolio of symptom science research conducted through the community oncology network supported by the US National Cancer Institute during the 12-year period 2008 to 2019.

METHODS

The National Cancer Institute conducted a retrospective review of the National Cancer Institute database to identify pediatric and adult symptom management studies that were opened between 2008 and 2019 in the community oncology network and to determine types of studies, accrual patterns, completed studies, and number of publications reporting clinical trial results.

RESULTS

The NCI community oncology network conducted 109 symptom studies between 2008 and 2019. The majority of these studies were phase II and III clinical trials. Neurotoxicities were the most frequently occurring symptom studied, with the majority of those focused on neurocognitive impairments. Gastrointestinal symptoms, pain, and fatigue were the next most frequently studied. A variety of interventions were utilized including pharmacologic, behavioral, complementary and alternative medicines, and radiation therapy. Accrual to symptom studies ranged from a low of 896 participants in 2008 to a high of 3468 participants in 2012. The number of open studies ranged from 8 in 2008 to 35 in 2012.

CONCLUSIONS

Examining the symptom science portfolio of the NCI community oncology network has identified research gaps and has highlighted the need to focus on a mechanistic understanding of symptoms and phenotyping of patients experiencing cancer and treatment-related symptoms. Subsequently, targeted interventions can be developed to prevent or treat these symptoms.

Differences in Normal Tissue Response in the Esophagus Between Proton and Photon Radiation Therapy for Non-Small Cell Lung Cancer Using In Vivo Imaging Biomarkers

PURPOSE

To determine whether there exists any significant difference in normal tissue toxicity between intensity modulated radiation therapy (IMRT) or proton therapy for the treatment of non-small cell lung cancer.

METHODS AND MATERIALS

A total of 134 study patients (n=49 treated with proton therapy, n=85 with IMRT) treated in a randomized trial had a previously validated esophageal toxicity imaging biomarker, esophageal expansion, quantified during radiation therapy, as well as esophagitis grade (Common Terminology Criteria for Adverse Events version 3.0), on a weekly basis during treatment. Differences between the 2 modalities were statically analyzed using the imaging biomarker metric value (Kruskal-Wallis analysis of variance), as well as the incidence and severity of esophagitis grade (χ² and Fisher exact tests, respectively). The dose-response of the imaging biomarker was also compared between modalities using esophageal equivalent uniform dose, as well as delivered dose to an isotropic esophageal subvolume.

RESULTS

No statistically significant difference in the distribution of esophagitis grade, the incidence of grade ≥3 esophagitis (15 and 11 patients treated with IMRT and proton therapy, respectively), or the esophageal expansion imaging biomarker between cohorts (P>.05) was found. The distribution of imaging biomarker metric values had similar distributions between treatment arms, despite a slightly higher dose volume in the proton arm (P>.05). Imaging biomarker dose-response was similar between modalities for dose quantified as esophageal equivalent uniform dose and delivered esophageal subvolume dose. Regardless of treatment modality, there was high variability in imaging biomarker response, as well as esophagitis grade, for similar esophageal doses between patients.

CONCLUSIONS

There was no significant difference in esophageal toxicity from either proton- or photon-based radiation therapy as quantified by esophagitis grade or the esophageal expansion imaging biomarker.

A Novel Methodology using CT Imaging Biomarkers to Quantify Radiation Sensitivity in the Esophagus with Application to Clinical Trials

Personalized cancer therapy seeks to tailor treatment to an individual patient's biology. Therefore, a means to characterize radiosensitivity is necessary. In this study, we investigated radiosensitivity in the normal esophagus using an imaging biomarker of radiation-response and esophageal toxicity, esophageal expansion, as a method to quantify radiosensitivity in 134 non-small-cell lung cancer patients, by using K-Means clustering to group patients based on esophageal radiosensitivity. Patients within the cluster of higher response and lower dose were labelled as radiosensitive. This information was used as a variable in toxicity prediction modelling (lasso logistic regression). The resultant model performance was quantified and compared to toxicity prediction modelling without utilizing radiosensitivity information. The esophageal expansion-response was highly variable between patients, even for similar radiation doses. K-Means clustering was able to identify three patient subgroups of radiosensitivity: radiosensitive, radio-normal, and radioresistant groups. Inclusion of the radiosensitive variable improved lasso logistic regression models compared to model performance without radiosensitivity information. Esophageal radiosensitivity can be quantified using esophageal expansion and K-Means clustering to improve toxicity prediction modelling. Finally, this methodology may be applied in clinical trials to validate pre-treatment biomarkers of esophageal toxicity.

Radical hypo-fractionated radiotherapy with volumetric modulated arc therapy in lung cancer : A retrospective study of elderly patients with stage III disease

BACKGROUND

This study aimed to analyse the feasibility and acute toxicity of radical hypo-fractionated radiotherapy (RT) for elderly patients with non-small-cell lung cancer (NSCLC).

PATIENTS AND METHODS

We conducted a retrospective evaluation of treatment with volumetric modulated arc therapy (VMAT) of elderly patients affected by stage III inoperable NSCLC. The dose prescription was 56 Gy in 20 fractions, 55 Gy in 22 fractions, or 50 Gy in 20 fractions. Target volume included only the primary lesion and the infiltrated lymph nodes. The primary end point was acute and late toxicity, while secondary end points were progression-free survival (PFS), and overall survival (OS).

RESULTS

In all, 41 patients were included in this analysis. The mean age of the patients was 78.6 years, and 22 patients had staged IIIA while 19 patients had stage IIIB disease. All but one patient had pathological nodal involvement; 15 patients received chemotherapy before RT. Acute grade 1-2 toxicity was recorded in 25 (61%) patients. Late toxicity was recorded in 13 (32%) patients. No cases of G3 or G4 toxicity were recorded. Complete response was obtained in two (5%) patients, 26 (63%) showed a partial response, and two (5%) experience disease progression. At a mean follow-up of 9.9 months (range, 1.1-25.4), 17 patients had died from disease progression, one died from other causes, and 23 were alive. Median OS was 13.7 ± 1.5 months (95% CI: 10.7-16.7), OS at 12 and 18 months was 51.3 ± 9.5% and 35.1 ± 10.1%, respectively. Median PFS was 13.7 ± 2.3 months (95% CI: 9.1-18.2), and PFS at 12 and 18 months was 50.1 ± 9.9% and 38.9 ± 10.4%, respectively.

CONCLUSION

Radical hypo-fractionated VMAT is a promising treatment for locally advanced NSCLC in the elderly. The use of hypo-fractionated radiotherapy for lung cancer in older patients can be considered a valuable approach, particularly for patients with poor performance status or refusing other treatment approaches.

(18)F-Fluorodeoxyglucose Positron Emission Tomography Can Quantify and Predict Esophageal Injury During Radiation Therapy

PURPOSE

We sought to investigate the ability of mid-treatment (18)F-fluorodeoxyglucose positron emission tomography (PET) studies to objectively and spatially quantify esophageal injury in vivo from radiation therapy for non-small cell lung cancer.

METHODS AND MATERIALS

This retrospective study was approved by the local institutional review board, with written informed consent obtained before enrollment. We normalized (18)F-fluorodeoxyglucose PET uptake to each patient's low-irradiated region (<5 Gy) of the esophagus, as a radiation response measure. Spatially localized metrics of normalized uptake (normalized standard uptake value [nSUV]) were derived for 79 patients undergoing concurrent chemoradiation therapy for non-small cell lung cancer. We used nSUV metrics to classify esophagitis grade at the time of the PET study, as well as maximum severity by treatment completion, according to National Cancer Institute Common Terminology Criteria for Adverse Events, using multivariate least absolute shrinkage and selection operator (LASSO) logistic regression and repeated 3-fold cross validation (training, validation, and test folds). This 3-fold cross-validation LASSO model procedure was used to predict toxicity progression from 43 asymptomatic patients during the PET study. Dose-volume metrics were also tested in both the multivariate classification and the symptom progression prediction analyses. Classification performance was quantified with the area under the curve (AUC) from receiver operating characteristic analysis on the test set from the 3-fold analyses.

RESULTS

Statistical analysis showed increasing nSUV is related to esophagitis severity. Axial-averaged maximum nSUV for 1 esophageal slice and esophageal length with at least 40% of axial-averaged nSUV both had AUCs of 0.85 for classifying grade 2 or higher esophagitis at the time of the PET study and AUCs of 0.91 and 0.92, respectively, for maximum grade 2 or higher by treatment completion. Symptom progression was predicted with an AUC of 0.75. Dose metrics performed poorly at classifying esophagitis (AUC of 0.52, grade 2 or higher mid treatment) or predicting symptom progression (AUC of 0.67).

CONCLUSIONS

Normalized uptake can objectively, locally, and noninvasively quantify esophagitis during radiation therapy and predict eventual symptoms from asymptomatic patients. Normalized uptake may provide patient-specific dose-response information not discernible from dose.

Objectively Quantifying Radiation Esophagitis With Novel Computed Tomography-Based Metrics

PURPOSE

To study radiation-induced esophageal expansion as an objective measure of radiation esophagitis in patients with non-small cell lung cancer (NSCLC) treated with intensity modulated radiation therapy.

METHODS AND MATERIALS

Eighty-five patients had weekly intra-treatment CT imaging and esophagitis scoring according to Common Terminlogy Criteria for Adverse Events 4.0, (24 Grade 0, 45 Grade 2, and 16 Grade 3). Nineteen esophageal expansion metrics based on mean, maximum, spatial length, and volume of expansion were calculated as voxel-based relative volume change, using the Jacobian determinant from deformable image registration between the planning and weekly CTs. An anatomic variability correction method was validated and applied to these metrics to reduce uncertainty. An analysis of expansion metrics and radiation esophagitis grade was conducted using normal tissue complication probability from univariate logistic regression and Spearman rank for grade 2 and grade 3 esophagitis endpoints, as well as the timing of expansion and esophagitis grade. Metrics' performance in classifying esophagitis was tested with receiver operating characteristic analysis.

RESULTS

Expansion increased with esophagitis grade. Thirteen of 19 expansion metrics had receiver operating characteristic area under the curve values >0.80 for both grade 2 and grade 3 esophagitis endpoints, with the highest performance from maximum axial expansion (MaxExp1) and esophageal length with axial expansion ≥30% (LenExp30%) with area under the curve values of 0.93 and 0.91 for grade 2, 0.90 and 0.90 for grade 3 esophagitis, respectively.

CONCLUSIONS

Esophageal expansion may be a suitable objective measure of esophagitis, particularly maximum axial esophageal expansion and esophageal length with axial expansion ≥30%, with 2.1 Jacobian value and 98.6 mm as the metric value for 50% probability of grade 3 esophagitis. The uncertainty in esophageal Jacobian calculations can be reduced with anatomic correction methods.

Phase 2 study of concurrent cetuximab plus definitive thoracic radiation therapy followed by consolidation docetaxel plus cetuximab in poor prognosis or elderly patients with locally advanced non-small cell lung cancer

BACKGROUND

Recursive partitioning analysis has shown that Eastern Cooperative Oncology Group (ECOG) Performance Status (PS) ≥2, male sex, and age ≥70 years are prognostic of poor outcome in locally advanced non-small cell lung cancer (LA-NSCLC) patients. Concurrent chemoradiation therapy (CRT) improves survival, but toxicity is a concern in this frail patient cohort. We therefore opened this trial of concurrent definitive thoracic radiation therapy (XRT) and cetuximab, followed by consolidation docetaxel plus cetuximab.

METHODS AND MATERIALS

Eligible patients had pathologically proven, unresectable LA-NSCLC (stage IIA-"dry" IIIB). They had ECOG PS 2 or weight loss ≥5% in 3 months or were aged ≥70 years. The primary objective was progression-free survival (PFS). Secondary objectives included overall survival (OS) and overall response rate (ORR).

RESULTS

From May 2008 to November 2010, a total of 32 patients were evaluated in our single-institution, institutional review board-approved prospective clinical trial. Three patients were screen failures and 2 more withdrew consent before treatment, leaving 27 evaluable patients. One was removed because of poor therapy compliance, and 2 were taken off trial because of grade 3 cetuximab-related toxicities but were followed up under intent-to-treat analysis. The median follow-up and OS were 10.5 months. The median PFS was 7.5 months. The ORR was 59.3%. Eight early/sudden deaths were reported. Upon review, 6 patients developed severe pulmonary complications.

CONCLUSIONS

Patients enrolled in this trial had improved OS compared with poor-PS historical controls (10.5 vs 6.4 months) and comparable OS to good-PS historical controls (10.5 vs 11.9 months) treated with XRT alone. However, pulmonary toxicity is a concern. Consolidative cetuximab/docetaxel, in conjunction with high-dose radiation therapy, is a putative cause.

Development of a symptom index for patients with primary brain tumors

OBJECTIVES

This study's primary goals included identifying the highest priority symptoms of patients with advanced brain tumors on treatment, comparing patient priority ratings with those of oncology experts, and constructing a brief symptom index using combined input to assess these symptoms and concerns.

METHODS

Fifty patients with advanced primary brain tumors and 10 physician experts were recruited from the National Comprehensive Cancer Network institutions and community support agencies. By using a 40-item symptom checklist, patients first selected up to 10 of the most important symptoms/concerns to monitor when assessing the value of drug treatment for brain tumors, then nominated up to 5 of the very most important concerns, and finally generated additional symptoms/concerns. By using the same checklist as patients, physicians rated each symptom/concern as disease- or treatment-related.

RESULTS

By using the combined input, a 24-item National Comprehensive Cancer Network/Functional Assessment of Cancer Therapy-Brain Symptom Index (NFBrSI-24) was developed. The NFBrSI-24 showed good internal consistency (α = 0.84), significantly differentiated patients with different levels of functional status (F2,47 = 8.21; P < .001), and demonstrated good convergent validity with the Functional Assessment of Cancer Therapy-General functional, physical, social, emotional, and brain tumor-specific concerns (ρ = 0.59, 0.57, 0.40, 0.35, and 0.50, respectively; Ps < 0.05).

CONCLUSIONS

The NFBrSI-24, an index of the symptoms in advanced brain tumors perceived as most important by both patients and clinicians, improves upon existing measures of brain tumor symptoms through better satisfaction of regulatory requirements for measure development. The findings suggest good reliability and validity, indicating that the NFBrSI-24 is a promising brief assessment of high-priority advanced brain tumor symptoms for research and clinical settings.

Portrayal of complementary and alternative medicine for cancer by top online news sites

BACKGROUND

Medical research news provided through the World Wide Web is easily accessible to the general public. Thus, it is necessary to understand how research findings released from online news sources are portrayed.

METHODS

The sample includes articles (n=205) published between January 1, 2010 and June 18, 2010 in top online news sites with competitive traffic rankings in the United States as determined by Alexa.com. Google Reader was used to find health-related news articles corresponding to the relevant news sources. Data analysis was performed using SPSS with two-tailed significance values of the χ(2) statistic.

RESULTS

A content analysis (n=205 stories) revealed that the majority of complementary and alternative medicine (CAM) modalities for cancer discussed in top online news sources are classified as nutritional therapeutics, and the cancer topic that appeared most frequently was that of prevention. General oncology was the most frequently cited cancer type that was discussed with regard to CAM. Medical journals were the most frequently cited source in CAM/cancer news articles. The majority of news stories on CAM/cancer were neutral in tone, and the relationship between tone and evidence type reported was statistically significant. Observational studies rather than randomized controlled trials were the predominant form of evidence provided for research findings.

CONCLUSIONS

Overall, the quality of how online news sources report research findings on complementary and alternative medicine therapies for cancer is fairly high. However, certain top online media sources are more reliable and informative than others when it comes to reporting about CAM remedies for cancer.

Patient self-reports of symptoms and clinician ratings as predictors of overall cancer survival

BACKGROUND

The National Cancer Institute's Common Terminology Criteria for Adverse Events (NCI-CTCAE) reporting system is widely used by clinicians to measure patient symptoms in clinical trials. The European Organization for Research and Treatment of Cancer's Quality of Life core questionnaire (EORTC QLQ-C30) enables cancer patients to rate their symptoms related to their quality of life. We examined the extent to which patient and clinician symptom scoring and their agreement could contribute to the estimation of overall survival among cancer patients.

METHODS

We analyzed baseline data regarding six cancer symptoms (pain, fatigue, vomiting, nausea, diarrhea, and constipation) from a total of 2279 cancer patients from 14 closed EORTC randomized controlled trials. In each trial that was selected for retrospective pooled analysis, both clinician and patient symptom scoring were reported simultaneously at study entry. We assessed the extent of agreement between clinician vs patient symptom scoring using the Spearman and kappa correlation statistics. After adjusting for age, sex, performance status, cancer severity, and cancer site, we used Harrell concordance index (C-index) to compare the potential for clinician-reported and/or patient-reported symptom scores to improve the accuracy of Cox models to predict overall survival. All P values are from two-sided tests.

RESULTS

Patient-reported scores for some symptoms, particularly fatigue, did differ from clinician-reported scores. For each of the six symptoms that we assessed at baseline, both clinician and patient scorings contributed independently and positively to the predictive accuracy of survival prognostication. Cox models of overall survival that considered both patient and clinician scores gained more predictive accuracy than models that considered clinician scores alone for each of four symptoms: fatigue (C-index = .67 with both patient and clinician data vs C-index = .63 with clinician data only; P <.001), vomiting (C-index = .64 vs .62; P = .01), nausea (C-index = .65 vs .62; P < .001), and constipation (C-index = .62 vs .61; P = .01).

CONCLUSION

Patients provide a subjective measure of symptom severity that complements clinician scoring in predicting overall survival.

Decreasing the adverse effects of cancer therapy: National Cancer Institute guidance for the clinical development of radiation injury mitigators

Recently, many agents have been identified that target molecular pathways that can mitigate radiation toxicity. To date, no drugs have been approved as radiation injury mitigators, which are defined as agents administered after irradiation but before toxicity is manifest. In order to accelerate the application of potential mitigators for cancer patients, a meeting sponsored by the National Cancer Institute (NCI) and National Institute of Allergy and Infectious Diseases (NIAID) was held in January 2010. This article presents an algorithm to guide clinical trials for such agents in patients receiving radiotherapy or radiochemotherapy. It reviews the mechanisms of radiation injury, the clinical problem, the preclinical and clinical development of candidate agents, and the design and conduct of clinical trials. The central role of patient reported outcomes is outlined, as well as key lessons learned from prior clinical trials. Ultimately, the goal is to be able to apply such promising agents to improve the quality of life for patients receiving radiotherapy or chemoradiotherapy for cancer.

Outcomes research in cancer symptom management trials: the Radiation Therapy Oncology Group (RTOG) conceptual model

The Radiation Therapy Oncology Group (RTOG) Health Services Research and Outcomes (HSRO) Committee aims to guide the study of the interactions among clinical, humanistic, and economic variables that optimize patient outcomes on clinical trials. To guide this work, the RTOG Outcomes Model was developed. Within this framework, measurement focuses primarily on patient-reported outcomes (PROs). In the examples presented, these outcomes have served to better quantify the benefit of one therapy over alternative therapies, as in the example of multimodality therapy for lung cancer, and to add evidence to clinical outcomes when clinical outcomes alone have not been strong enough to change clinical practice, as in the example of palliative radiotherapy for painful bone metastasis. The unique contribution to the RTOG of the HSRO Committee is the selection and use of PRO measures that give "voice" to the patient in clinical trials as well as provide data to better manage symptoms.

Issues and challenges with integrating patient-reported outcomes in clinical trials supported by the National Cancer Institute-sponsored clinical trials networks

PURPOSE

The objective of this report is to provide a historical overview of and the issues and challenges inherent in the incorporation of patient-reported outcomes (PROs) into multinational cancer clinical trials in the cancer cooperative groups.

METHODS

An online survey of 12 cancer cooperative groups from the United States, Canada, and Europe was conducted between June and August of 2006. Each of the cooperative groups designated one respondent, who was a member of one of the PRO committees within the cooperative group.

RESULTS

There was a 100% response rate, and all of the cancer clinical trial cooperative groups reported conducting PRO research. PRO research has been conducted in the cancer cooperative groups for an average of 15 years (range, 6 to 30 years), and all groups had multidisciplinary committees focused on the design of PRO end points and the choice of appropriate PRO measures for cancer clinical trials. The cooperative groups reported that 5% to 50% of cancer treatment trials and an estimated 50% to 75% of cancer control trials contained PRO primary and secondary end points. There was considerable heterogeneity among the cooperative groups with respect to the formal and informal policies and procedures or cooperative group culture towards PROs, investigator training/mentorship, and resource availability for the measurement and conduct of PRO research within the individual cooperatives.

CONCLUSION

The challenges faced by the cooperative groups to the incorporation of PROs into cancer clinical trials are varied. Some common opportunities for improvement include the adoption of standardized training/mentorship mechanisms for investigators for the conduct of PRO assessments and data collection and the development of minimal criteria for PRO measure acceptability. A positive cultural shift has occurred in most of the cooperative groups related to the incorporation of PROs in clinical trials; however, financial and other resource barriers remain and need to be addressed.

Randomized trial results of quality of life comparing whole abdominal irradiation and combination chemotherapy in advanced endometrial carcinoma: A gynecologic oncology group study

OBJECTIVE

To prospectively compare quality of life (QOL) outcomes in patients with advanced endometrial cancer treated with whole abdominal irradiation (WAI) or doxorubicin-cisplatin (AP) chemotherapy.

METHODS

Using the Fatigue Scale (FS), Assessment of Peripheral Neuropathy (APN), Functional Alterations due to Changes in Elimination (FACE), and Functional Assessment of Cancer Therapy-General (FACT-G), QOL was measured at: pre-treatment, end of treatment (EOT), and 3 and 6 months post-treatment.

RESULTS

317 of 396 eligible patients provided a baseline QOL assessment. The AP arm produced a statistically significant survival benefit along with greater toxicities, including peripheral neuropathy persisting up to 6 months. WAI patients reported worse FS (p < 0.001) and FACE (p < 0.001) scores at EOT and poorer FACE scores 3 months post-treatment (p = 0.004) compared to AP patients. APN scores were significantly worse among AP patients at EOT, and 3 and 6 months post-treatment (p < 0.001 for all). There is no indication that FACT-G scores differed between the two arms at any assessment point.

CONCLUSIONS

The trade-off for increased survival with AP is its potential for clinically significant peripheral neuropathy. This should be discussed with patients, particularly those who work with their hands or on their feet, in weighing therapeutic choices. Further research is needed to manage side effects having an enduring impact on QOL.

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.

Quality-of-Life Outcomes in Oncology

QOL outcomes have become an integral component of many clinical oncology trials. Much work has been performed testing the validity and reliability of Q OL instruments. The current challenge is to understand better the clinical relevance of QOL research in oncology. QOL studies should focus on phase III trials with clear hypotheses that can lead to clinically meaningful interventions.

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

PURPOSE

To evaluate the factors associated with acute esophagitis in lung cancer patients treated with thoracic radiotherapy.

METHODS AND MATERIALS

We examined 35 patients with non-small-cell lung cancer (n = 27, 77%) and small-cell lung cancer (n = 8, 23%) treated with thoracic radiotherapy between February 2003 and November 2004. The median patient age was 70 years (range, 50-83 years). The disease stage was Stage I in 2 patients (6%), Stage II in 1 (3%), Stage IIIa in 10 (28%), Stage IIIb in 9 (26%), and Stage IV in 9 (26%); 4 patients (11%) had recurrent disease after surgery. A median dose of 60 Gy (range, 50-67 Gy) was given to the isocenter and delivered in single daily fractions of 1.8 or 2 Gy. With heterogeneity corrections, the median given dose to the isocenter was 60.3 Gy (range, 49.9-67.2 Gy). Of the 35 patients, 30 (86%) received concurrent chemotherapy consisting of a platinum agent, cisplatin or carboplatin, combined with paclitaxel in 18 patients (52%), irinotecan hydrochloride in 7 (20%), vincristine sulfate and etoposide in 2 (5%), vinorelbine ditartrate in 1 (3%), etoposide in 1 (3%), and docetaxel in 1 patient (3%). Three of these patients underwent induction therapy with cisplatin and irinotecan hydrochloride, administered before thoracic radiotherapy, and concurrent chemotherapy. Esophageal toxicity was graded according to the Radiation Therapy Oncology Group criteria. The following factors were analyzed with respect to their association with Grade 1 or worse esophagitis by univariate and multivariate analyses: age, gender, concurrent chemotherapy, chemotherapeutic agents, maximal esophageal dose, mean esophageal dose, and percentage of esophageal volume receiving >10 to >65 Gy in 5-Gy increments.

RESULTS

Of the 35 patients, 25 (71%) developed acute esophagitis, with Grade 1 in 20 (57%) and Grade 2 in 5 (14%). None of the patients had Grade 3 or worse toxicity. The most significant correlation was between esophagitis and percentage of esophageal volume receiving >35 Gy on univariate (p = 0.002) and multivariate (p = 0.018) analyses.

CONCLUSION

The percentage of esophageal volume receiving >35 Gy was the most statistically significant factor associated with mild acute esophagitis.