The effect of radiotherapy dose on survival in stage III non-small-cell lung cancer patients undergoing definitive chemoradiotherapy

Optimal Radiation Dose for Stage III Lung Cancer-Should "Definitive" Radiation Doses Be Used in the Preoperative Setting?

Introduction

There are currently two recommended radiation strategies for clinical stage III NSCLC: a lower "preoperative" (45-54 Gy) and a higher "definitive/nonsurgical" (60-70 Gy) dose. We sought to determine if definitive radiation doses should be used in the preoperative setting given that many clinical stage III patients planned for surgery are ultimately managed with chemoradiation alone.

Methods

Using the National Cancer Database data from 2006 to 2016, we performed a comparative effectiveness analysis of stage III N2 patients who received chemoradiotherapy. Patients were stratified into subgroups across 2 parameters: (1) radiation dose: lower (45-54 Gy) and higher (60-70 Gy); and (2) the use of surgery (i.e., surgical and nonsurgical treatment approaches). Long-term survival and perioperative outcomes were evaluated using multivariable Cox proportional hazards and logistic regression models.

Results

A cohort of 961 patients received radiation before surgery including 321 who received a higher dose and 640 who received a lower dose. A higher preoperative dose revealed similar long-term mortality risk (hazard ratio = 0.99, 95% confidence interval: 0.82-1.21, p = 0.951) compared with a lower dose. There was no significant association between radiation dose and 90-day mortality (p = 0.982), 30-day readmission (p = 0.931), or prolonged length of stay (p = 0.052) in the surgical cohort. A total of 17,904 clinical-stage IIIA-N2 patients were treated nonsurgically, including 15,945 receiving higher and 1959 treated with a lower dose. A higher dose was associated with a reduction in long-term mortality risk (hazard ratio = 0.64, 95% confidence interval: 0.60-0.67, p < 0.001) compared with a lower dose.

Conclusions

For clinical stage III NSCLC, the administration of 60 to 70 Gy of radiation seems to be more effective than the lower dose for nonsurgical patients without compromising surgical safety for those that undergo resection. This evidence supports the implementation of 60 to 70 Gy as a single-dose strategy for both preoperative and definitive chemoradiotherapy.

Stage III Non-Small-Cell Lung Cancer Treated With Concurrent Chemoradiation Followed or Not by Consolidation Chemotherapy: A Survival Analysis From a Brazilian Multicentric Cohort

Purpose

Of newly diagnosed patients with non–small-cell lung cancer (NSCLC), stage III accounts for 30%. Most patients are treated with concurrent chemoradiation therapy, but the addition of consolidation chemotherapy (CC) is debatable. We examined the effect of CC in Brazilian patients with stage III NSCLC treated in routine clinical practice.

Methods

We retrospectively collected data for patients from five different Brazilian cancer institutions who had stage III NSCLC and who were treated with chemoradiation therapy followed or not by CC. Eligible patients were age 18 years or older and must have been treated with cisplatin-carboplatin plus etoposide, paclitaxel, or vinorelbine, concurrently with thoracic radiation therapy (RT). Patients treated with surgery or neoadjuvant chemotherapy were excluded. The primary end point was overall survival (OS). Associations between CC and clinical variables and demographics were evaluated by using Pearson’s χ² test. Survival curves were calculated by using the Kaplan-Meier method and were compared using the log-rank test. Univariable and multivariable analysis used a Cox proportional hazards model.

Results

We collected data from 165 patients. Median age was 60 years. Most patients were male (69.1%), white (77.9%), current or former smokers (93.3%), and had stage IIIB disease (52.7%). Adenocarcinoma was the most common histology (47.9%). Weight loss of more than 5% was observed in 39.1% and Eastern Cooperative Oncology Group performance status of 2 was observed in 14.6%. The only variable associated with CC was T stage (P = .022). We observed no statistically significant difference in OS between patients treated or not with CC (P = .128). A total delivered RT dose ≥ 61 Gy was the only variable independently associated with improved survival (P = .012).

Conclusion

Brazilian patients with locally advanced NSCLC who were treated with standard treatment achieved OS similar to that reported in randomized trials. CC did not improve OS in patients with stage III NSCLC after concurrent chemoradiation therapy. An RT dose of less than 61 Gy had a negative effect on OS.

Association between intensity modulated radiotherapy and survival in patients with stage III non-small cell lung cancer treated with chemoradiotherapy

PURPOSE

To determine the effect of radiotherapy (RT) technique on treatment compliance and overall survival (OS) in patients with stage III non-small lung cancer (NSCLC) treated with definitive chemoradiotherapy (CRT).

METHODS AND MATERIALS

This study included patients with stage III NSCLC in the National Cancer Database treated between 2003 and 2011 with definitive CRT to 60-63 Gray (Gy). Radiation treatment interruption (RTI) was defined as a break of ≥4 days. Treatment technique was dichotomized as intensity modulated (IMRT) or non-IMRT techniques.

RESULTS

Out of the cohort of 7492, 35% had a RTI and 10% received IMRT. With a median follow-up of surviving patients of 32 months, the median survival for those with non-IMRT vs. IMRT was 18.2 months vs. 20 months (p<0.0001). Median survival for those with and without an RTI≥4 days was 16.1 months vs. 19.8 months (p<0.0001). Use of IMRT predicted for a decreased likelihood of RTI (odds ratio, 0.84, p=0.04). On multivariable analysis for OS, IMRT had a HR of 0.89 (95% CI: 0.80-0.98, p=0.01) and RTI had a HR of 1.2 (95% confidence interval (CI): 1.14-1.27, p=0.001).

CONCLUSIONS

IMRT was associated with small but significant survival advantage for patients with stage III NSCLC treated with CRT. A RTI led to inferior survival, and both IMRT and RTI were independently associated with OS. Additional research should investigate whether improved tolerability, reduced normal tissue exposure, or superior coverage drives the association between IMRT and improved survival.

A population-based comparative effectiveness study of chemoradiation regimens and sequences in stage III non-small cell lung cancer

OBJECTIVES

In patients receiving concurrent chemoradiation for locally advanced non-small cell lung cancer (NSCLC), consolidation chemotherapy is frequently given even though several randomized trials have failed to show a benefit. We explored the potential benefits of consolidation chemotherapy using a population-based comparative effectiveness approach.

MATERIALS AND METHODS

Surveillance, Epidemiology, and End Results-Medicare was used to identify patients with Stage III NSCLC aged ≥65 and diagnosed 2002-2009. We selected patients who received concurrent chemoradiotherapy and determined whether they were (concurrent-consolidation) or were not (concurrent-alone) treated with consolidation chemotherapy. Outcomes were overall and cancer specific survival using a conditional landmark analysis approach.

RESULTS

1688 patients treated with concurrent-alone or concurrent-consolidation were identified with a median follow up of 29 months. Choice of chemotherapy agents did not correlate with outcome. For concurrent-consolidation versus concurrent-alone, the median overall survival was 21 months versus 18 months, respectively (log-rank p=0.008) and the median cancer specific survival was 23 months versus 19 months, respectively (log-rank p=0.03). On multivariate analysis, concurrent-consolidation remained associated with improved overall survival (HR 0.85, p=0.04), and there was a trend for improved cancer specific survival (HR 0.87, p=0.12). Inverse probability of treatment weighting using propensity scores demonstrated similar findings. Importantly, the benefit of concurrent-consolidation held only for patients treated with carboplatin-taxane but not with cisplatin-etoposide.

CONCLUSION

Survival outcomes were similar among the five most commonly employed platinum-based doublets. We found that patients receiving cisplatin during radiation do not appear to benefit from additional chemotherapy. However, for patients receiving carboplatin, consolidation chemotherapy was associated with improved overall and cancer specific survival.

Improved survival with dose-escalated radiotherapy in stage III non-small-cell lung cancer: analysis of the National Cancer Database

BACKGROUND

Concurrent chemoradiation is the standard of care in non-operable stage III non-small-cell lung cancer (NSCLC). Data have suggested a benefit of dose escalation; however, results from the randomized dose-escalation trial RTOG 0617 revealed a lower survival rate with high-dose radiation. To evaluate the impact of dose escalation on overall survival (OS) in stage III NSCLC treated with chemoradiotherapy outside the controlled setting of a randomized trial, we carried out an observational, population-based investigation of the National Cancer Database (NCDB).

PATIENTS AND METHODS

A total of 33 566 patients with stage III NSCLC treated with chemoradiation from 2004 to 2012 and radiation doses between 59.4 and 85 Gy were included. The primary end point was OS, with median survival calculated via Kaplan-Meier. Univariate, multivariable and propensity-score matching analyses were carried out.

RESULTS

Patients were stratified by dose with median OS of: 18.8, 19.8 and 21.6 months for cohorts receiving 59.4-60, 61-69 and ≥70 Gy, respectively (P < 0.001). Granular dose analyses were carried out demonstrating increased OS with increasing radiation dose: median survival of 18.8, 21.1, 22.0 and 21.0 months for 59.4-60, 66, 70 and ≥71 Gy, respectively. While 66, 70 and ≥71 Gy resulted in increased OS in comparison with 59.4-60 Gy, no significant difference in OS was observed when comparing 66 with ≥71 Gy (P = 0.38).

CONCLUSIONS

Dose escalation above 60 Gy was associated with improved OS in this cohort of stage III NSCLC patients treated with chemoradiotherapy. A plateau of benefit was observed, with no additional improvement in OS with increased dose (≥71 Gy) compared with 66-70 Gy. With evidence suggesting worse OS and quality of life with increased dose, these data support investigation of the role of intermediate-dose radiation, and in the absence of randomized evidence, may be leveraged to justify utilization of intermediate-dose radiation.

Patients Selected for Definitive Concurrent Chemoradiation at High-volume Facilities Achieve Improved Survival in Stage III Non-Small-Cell Lung Cancer

BACKGROUND

The relationship between provider experience and clinical outcomes is poorly defined in radiation oncology. This study examined the impact of facility case volume on overall survival in patients with stage III non-small cell lung cancer (NSCLC) treated with definitive concurrent chemoradiation therapy (CCRT).

METHODS

Using the National Cancer Data Base, we identified clinical stage III NSCLC patients diagnosed in 2004 to 2006 who were treated with definitive CCRT to 59.4-74.0 Gy. High-volume facilities (HVF) were defined as those in the ninetieth percentile of annual CCRT volume (≥12 cases/year). Independent predictors of receiving CCRT at HVF were identified using multivariable logistic regression. Overall survival based on receiving CCRT at HVF was assessed using Kaplan-Meier analysis, Cox proportional hazards regression, and propensity score matching.

RESULTS

Among 10,072 included patients, 1207 (12.0%) were treated at HVF. Patients in HVF were more likely to have a higher Charlson-Deyo comorbidity score, more advanced nodal stage, higher doses, and 3D-conformal or intensity-modulated radiotherapy. When controlling for demographic and clinical covariates including academic affiliation, treatment at HVF was independently associated with a significantly decreased risk of death (hazards ratio = 0.93; 95% confidence interval: 0.87-0.99; p = 0.03). Propensity score matching showed that these findings were robust (hazards ratio = 0.91; 95% confidence interval: 0.84-0.99; p = 0.04).

CONCLUSIONS

Our findings suggest that treatment at HVF is associated with improved overall survival among stage III NSCLC patients receiving definitive CCRT, independent of academic affiliation. Further research is needed to determine whether or not efforts supporting centralization of radiotherapy at HVF will improve population-based survival, toxicities, and costs.

Accelerated hypofractionated radiotherapy with concomitant chemotherapy in locally advanced squamous cell carcinoma of lung: evaluation of response, survival, toxicity and quality of life from a Phase II randomized study

OBJECTIVE

To evaluate the feasibility and efficacy of accelerated hypofractionated radiation with concomitant chemotherapy (AHFx-RT-CT) in locally advanced squamous cell carcinoma (SCC) of the lung.

METHODS

36 patients were enrolled in this study (CTRI/2013/11/004143). Patients in Arm A (n = 18) received neoadjuvant chemotherapy (NACT) (paclitaxel 200 mg m(-2) and carboplatin area under the curve 5) followed by external radiotherapy (60 Gy/30 fractions/6 weeks). Patients in Arm B (n = 18) received NACT as in Arm A followed by AHFx-RT (48 Gy/20 fractions/4 weeks) with concomitant chemotherapy (cisplatin 30 mg m(-2) weekly). Primary end points included comparative evaluation of overall locoregional response rates (ORRs) and progression-free survival (PFS). Secondary end points included toxicity, quality of life (QOL) and overall survival (OS).

RESULTS

The median follow-up duration was 15 months. The ORR at first follow-up (72.2% vs 44%, p = 0.06) and at 1 year after treatment completion (61% vs 5.5%, p = 0.04) were superior in Arm B. The median PFS (17 vs 5.36 months; p = 0.053) and OS (24.73 vs 12.33 months; p = 0.007) were also superior in Arm B. Grade ≥3 acute pharyngitis/oesophagitis was less in Arm B (p = 0.05). Improvement of emotional function, cognitive function and chest pain was observed in Arm B.

CONCLUSION

The study suggests that AHFx-RT-CT is feasible for locally advanced SCC of the lung with improved response rate, survival, QOL and favourable toxicity.

ADVANCES IN KNOWLEDGE

To the best of our knowledge, this is the first study comparing conventionally fractionated radiation with AHFx-RT-CT. Addition of low-dose weekly cisplatin as radiosensitizer may be the potential factor responsible for improved response rate, survival and favourable toxicity in the study arm despite lower biological effective dose.

A Validated Prediction Model for Overall Survival From Stage III Non-Small Cell Lung Cancer: Toward Survival Prediction for Individual Patients

PURPOSE

Although patients with stage III non-small cell lung cancer (NSCLC) are homogeneous according to the TNM staging system, they form a heterogeneous group, which is reflected in the survival outcome. The increasing amount of information for an individual patient and the growing number of treatment options facilitate personalized treatment, but they also complicate treatment decision making. Decision support systems (DSS), which provide individualized prognostic information, can overcome this but are currently lacking. A DSS for stage III NSCLC requires the development and integration of multiple models. The current study takes the first step in this process by developing and validating a model that can provide physicians with a survival probability for an individual NSCLC patient.

METHODS AND MATERIALS

Data from 548 patients with stage III NSCLC were available to enable the development of a prediction model, using stratified Cox regression. Variables were selected by using a bootstrap procedure. Performance of the model was expressed as the c statistic, assessed internally and on 2 external data sets (n=174 and n=130).

RESULTS

The final multivariate model, stratified for treatment, consisted of age, gender, World Health Organization performance status, overall treatment time, equivalent radiation dose, number of positive lymph node stations, and gross tumor volume. The bootstrapped c statistic was 0.62. The model could identify risk groups in external data sets. Nomograms were constructed to predict an individual patient's survival probability (www.predictcancer.org). The data set can be downloaded at https://www.cancerdata.org/10.1016/j.ijrobp.2015.02.048.

CONCLUSIONS

The prediction model for overall survival of patients with stage III NSCLC highlights the importance of combining patient, clinical, and treatment variables. Nomograms were developed and validated. This tool could be used as a first building block for a decision support system.