Clinical Nomogram Using Novel Computed Tomography-Based Radiomics Predicts Survival in Patients With Non-Small-Cell Lung Cancer Treated With Stereotactic Body Radiation Therapy

PURPOSE

Improved survival prediction and risk stratification in non-small-cell lung cancer (NSCLC) would lead to better prognosis counseling, adjuvant therapy selection, and clinical trial design. We propose the persistent homology (PHOM) score, the radiomic quantification of solid tumor topology, as a solution.

MATERIALS AND METHODS

Patients diagnosed with stage I or II NSCLC primarily treated with stereotactic body radiation therapy (SBRT) were selected (N = 554). The PHOM score was calculated for each patient's pretreatment computed tomography scan (October 2008-November 2019). PHOM score, age, sex, stage, Karnofsky Performance Status, Charlson Comorbidity Index, and post-SBRT chemotherapy were predictors in the Cox proportional hazards models for OS and cancer-specific survival. Patients were split into high- and low-PHOM score groups and compared using Kaplan-Meier curves for overall survival (OS) and cumulative incidence curves for cause-specific death. Finally, we generated a validated nomogram to predict OS, which is publicly available at Eashwarsoma.Shinyapps.

RESULTS

PHOM score was a significant predictor for OS (hazard ratio [HR], 1.17; 95% CI, 1.07 to 1.28) and was the only significant predictor for cancer-specific survival (1.31; 95% CI, 1.11 to 1.56) in the multivariable Cox model. The median survival for the high-PHOM group was 29.2 months (95% CI, 23.6 to 34.3), which was significantly worse compared with the low-PHOM group (45.4 months; 95% CI, 40.1 to 51.8; P < .001). The high-PHOM group had a significantly greater chance of cancer-specific death at post-treatment month 65 (0.244; 95% CI, 0.192 to 0.296) compared with the low-PHOM group (0.171; 95% CI, 0.123 to 0.218; P = .029).

CONCLUSION

The PHOM score is associated with cancer-specific survival and predictive of OS. Our developed nomogram can be used to inform clinical prognosis and assist in making post-SBRT treatment considerations.

Smoking Cessation, Version 3.2022, NCCN Clinical Practice Guidelines in Oncology

Although the harmful effects of smoking after a cancer diagnosis have been clearly demonstrated, many patients continue to smoke cigarettes during treatment and beyond. The NCCN Guidelines for Smoking Cessation emphasize the importance of smoking cessation in all patients with cancer and seek to establish evidence-based recommendations tailored to the unique needs and concerns of patients with cancer. The recommendations contained herein describe interventions for cessation of all combustible tobacco products (eg, cigarettes, cigars, hookah), including smokeless tobacco products. However, recommendations are based on studies of cigarette smoking. The NCCN Smoking Cessation Panel recommends that treatment plans for all patients with cancer who smoke include the following 3 tenets that should be done concurrently: (1) evidence-based motivational strategies and behavior therapy (counseling), which can be brief; (2) evidence-based pharmacotherapy; and (3) close follow-up with retreatment as needed.

Esophageal adenocarcinoma: A dire need for early detection and treatment

Esophageal cancer is the sixth most common cause of cancer-related death worldwide. Esophageal adenocarcinoma is the most common subtype of esophageal cancer in the United States, and its incidence has risen dramatically in the last few decades. Modern endoscopic and surgical techniques have significantly improved morbidity and mortality rates of patients undergoing treatment for esophageal cancer. However, most cases are diagnosed at a late stage when the prognosis is poor, emphasizing the need for an effective screening strategy. This clinical overview focuses on screening, multidisciplinary evaluation, and treatment of early esophageal adenocarcinoma.

Prophylactic Cranial Irradiation vs Observation in Patients With Locally Advanced Non-Small Cell Lung Cancer: A Long-term Update of the NRG Oncology/RTOG 0214 Phase 3 Randomized Clinical Trial

Importance

Brain metastasis (BM) rates are high in locally advanced non-small cell lung cancer (LA-NSCLC), approaching rates seen in small cell lung cancer, where prophylactic cranial irradiation (PCI) is standard of care. Although PCI decreases the incidence of BM in LA-NSCLC, a survival advantage has not yet been shown.

Objective

To determine if PCI improves survival in LA-NSCLC.

Design, Setting, and Participants

Radiation Therapy Oncology Group (RTOG) 0214 was a randomized phase 3 clinical trial in stage III NSCLC stratified by stage (IIIA vs IIIB), histologic characteristics (nonsquamous vs squamous) and therapy (no surgery vs surgery). The study took place at 291 institutions in the United States, Canada, and internationally. Of 356 patients with stage III NSCLC entered onto this study, 16 were ineligible; therefore, 340 patients were randomized.

Intervention for Clinical Trials

Observation vs PCI.

Main Outcomes and Measures

The primary outcome was overall survival (OS). The secondary end points were disease-free survival (DFS) and incidence of BM.

Results

Of the 340 total participants, mean (SD) age was 61 years; 213 of the participants were men and 127 were women. The median follow-up time was 2.1 years for all patients, and 9.2 years for living patients. The OS for PCI was not significantly better than observation (hazard ratio [HR], 0.82; 95% CI, 0.63-1.06; P = .12; 5- and 10-year rates, 24.7% and 17.6% vs 26.0% and 13.3%, respectively), while the DFS (HR, 0.76; 95% CI, 0.59-0.97; P = .03; 5- and 10-year rates, 19.0% and 12.6% vs 16.1% and 7.5% for PCI vs observation) and BM (HR, 0.43; 95% CI, 0.24-0.77; P = .003; 5- and 10-year rates, 16.7% vs 28.3% for PCI vs observation) were significantly different. Patients in the PCI arm were 57% less likely to develop BM than those in the observation arm. Younger patients (<60 years) and patients with nonsquamous disease developed more BM. On multivariable analysis, PCI was associated with decreased BM and improved DFS, but not improved OS. Multivariable analysis within the nonsurgical arm suggests that PCI effectively prolongs OS, DFS, and BM.

Conclusions and Relevance

In patients with stage III LA-NSCLC without progression of disease after therapy, PCI decreased the 5- and 10-year rate of BM and improved 5- and 10-year DFS, but did not improve OS. Although this study did not meet its primary end point, the long-term results reveal many important findings that will benefit future trials. Identifying the appropriate patient population and a safe intervention is critical.

Trial Registration

ClinicalTrials.gov identifier: NCT00048997.

Treatment-Related Predictive and Prognostic Factors in Trimodality Approach in Stage IIIA/N2 Non-Small Cell Lung Cancer

While there are no established pretreatment predictive and prognostic factors in patients with stage IIIA/pN2 non-small cell lung cancer (NSCLC) indicating a benefit to surgery as a part of trimodality approach, little is known about treatment-related predictive and prognostic factors in this setting. A literature search was conducted to identify possible treatment-related predictive and prognostic factors for patients for whom trimodality approach was reported on. Overall survival was the primary endpoint of this study. Of 30 identified studies, there were two phase II studies, 5 “prospective” studies, and 23 retrospective studies. No study was found which specifically looked at treatment-related predictive factors of improved outcomes in trimodality treatment. Of potential treatment-related prognostic factors, the least frequently analyzed factors among 30 available studies were overall pathologic stage after preoperative treatment and UICC downstaging. Evaluation of treatment response before surgery and by pathologic tumor stage after induction therapy were analyzed in slightly more than 40% of studies and found not to influence survival. More frequently studied factors—resection status, degree of tumor regression, and pathologic nodal stage after induction therapy as well as the most frequently studied factor, the treatment (in almost 75% studies)—showed no discernible impact on survival, due to conflicting results. Currently, it is impossible to identify any treatment-related predictive or prognostic factors for selecting surgery in the treatment of patients with stage IIIA/pN2 NSCLC.

Effect of the Addition of Cetuximab to Paclitaxel, Cisplatin, and Radiation Therapy for Patients With Esophageal Cancer: The NRG Oncology RTOG 0436 Phase 3 Randomized Clinical Trial

Importance

The role of epidermal growth factor receptor (EGFR) inhibition in chemoradiation strategies in the nonoperative treatment of patients with esophageal cancer remains uncertain.

Objective

To evaluate the benefit of cetuximab added to concurrent chemoradiation therapy for patients undergoing nonoperative treatment of esophageal carcinoma.

Design, Setting, and Participants

A National Cancer Institute (NCI) sponsored, multicenter, phase 3, randomized clinical trial open to patients with biopsy-proven carcinoma of the esophagus. The study accrued 344 patients from 2008 to 2013.

Interventions

Patients were randomized to weekly concurrent cisplatin (50 mg/m2), paclitaxel (25 mg/m2), and daily radiation of 50.4 Gy/1.8 Gy fractions with or without weekly cetuximab (400 mg/m2 on day 1 then 250 mg/m2 weekly).

Main Outcomes and Measures

Overall survival (OS) was the primary endpoint, with a study designed to detect an increase in 2-year OS from 41% to 53%; 80% power and 1-sided α = .025.

Results

Between June 30, 2008, and February 8, 2013, 344 patients were enrolled. This analysis used all data received at NRG Oncology through April 12, 2015. Sixteen patients were ineligible, resulting in 328 evaluable patients, 159 in the experimental arm and 169 in the control arm. Patients were well matched between the treatment arms for patient and tumor characteristics: 263 (80%) with T3 or T4 disease, 215 (66%) N1, and 62 (19%) with celiac nodal involvement. Incidence of grade 3, 4, or 5 treatment-related adverse events at any time was 71 (46%), 35 (23%), or 6 (4%) in the experimental arm and 83 (50%), 28 (17%), or 2 (1%) in the control arm, respectively. A clinical complete response (cCR) rate of 81 (56%) was observed in the experimental arm vs 92 (58%) in the control arm (Fisher exact test, P = .66). No differences were seen in cCR between treatment arms for either histology (adenocarcinoma or squamous cell). Median follow-up for all patients was 18.6 months. The 24- and 36-month local failure for the experimental arm was 47% (95% CI, 38%-57%) and 49% (95% CI, 40%-59%) vs 49% (95% CI, 41%-58%) and 49% (95% CI, 41%-58%) for the control arm (HR, 0.92; 95% CI, 0.66-1.28; P = .65). The 24- and 36-month OS rates for the experimental arm were 45% (95% CI, 37%-53%) and 34% (95% CI, 26%-41%) vs 44% (95% CI, 36%-51%) and 28% (95% CI, 21%-35%) for the control arm (HR, 0.90; 95% CI, 0.70-1.16; P = .47).

Conclusions and Relevance

The addition of cetuximab to concurrent chemoradiation did not improve OS. These phase 3 trial results point to little benefit to current EGFR-targeted agents in an unselected patient population, and highlight the need for predictive biomarkers in the treatment of esophageal cancer.

Trial Registration

clinicaltrials.gov Identifier: NCT00655876.

ASTRO's Advances in Radiation Oncology: Success to date and future plans

ASTRO's Advances in Radiation Oncology was launched as a new, peer-reviewed scientific journal in December 2015. More than 200 manuscripts have been submitted and 97 accepted for publication as of May 2017. As Advances enters its second year of publication, we have chosen to highlight subjects that will transform the way we practice radiation oncology in special issues or ongoing series: immunotherapy, biomedical analytics, and social media. A teaching case report contest for North American radiation oncology residents will be launched at American Society of Radiation Oncology 2017 to encourage participation in scientific publication by trainees early in their careers. Recognizing our social mission, Advances will also begin a series of articles devoted to highlighting the growing disparities in access to radiation oncology services in vulnerable populations in North America. We wish to encourage the American Society of Radiation Oncology membership to continue its support of the journal through high-quality manuscript submission, participation in the peer review process, and highlighting important manuscripts through sharing on social media.

Combined modality therapy in Stage IIIA non-small cell lung cancer: clarity or confusion despite the highest level of evidence?

Recent years have witnessed a number of clinical trials in Stage IIIA non-small cell lung cancer (NSCLC) comparing (A) induction chemotherapy (CHT) with induction CHT and radiotherapy (RT), each followed by surgery; (B) either induction CHT or induction RT-CHT, each followed by surgery, with definitive RT-CHT (no surgery). Due to the heterogeneity of patient, tumor and treatment characteristics across these trials, various meta-analyses (MAs) have been performed to define the optimal treatment approach in this setting for this clinical presentation. Six such MAs exist. In spite of the differences between MAs, it appears that RT does not add extra benefit to induction CHT administered before surgery, and that a trimodality (i.e. including surgery) regimen is not superior to definitive concurrent RT-CHT. While one can consider both induction CHT followed by surgery and exclusive concurrent RT-CHT as feasible in this setting, lack of pre-treatment predictive factors identifying patients who might preferentially benefit from a surgical approach limits its use to well-planned clinical trials.

Dose differences in intensity-modulated radiotherapy plans calculated with pencil beam and Monte Carlo for lung SBRT

For patients with medically inoperable early‐stage non‐small cell lung cancer (NSCLC) treated with stereotactic body radiation therapy, early treatment plans were based on a simpler dose calculation algorithm, the pencil beam (PB) calculation. Because these patients had the longest treatment follow‐up, identifying dose differences between the PB calculated dose and Monte Carlo calculated dose is clinically important for understanding of treatment outcomes. Previous studies found significant dose differences between the PB dose calculation and more accurate dose calculation algorithms, such as convolution‐based or Monte Carlo (MC), mostly for three‐dimensional conformal radiotherapy (3D CRT) plans. The aim of this study is to investigate whether these observed dose differences also exist for intensity‐modulated radiotherapy (IMRT) plans for both centrally and peripherally located tumors. Seventy patients (35 central and 35 peripheral) were retrospectively selected for this study. The clinical IMRT plans that were initially calculated with the PB algorithm were recalculated with the MC algorithm. Among these paired plans, dosimetric parameters were compared for the targets and critical organs. When compared to MC calculation, PB calculation overestimated doses to the planning target volumes (PTVs) of central and peripheral tumors with different magnitudes. The doses to 95% of the central and peripheral PTVs were overestimated by 9.7%±5.6% and 12.0%±7.3%, respectively. This dose overestimation did not affect doses to the critical organs, such as the spinal cord and lung. In conclusion, for NSCLC treated with IMRT, dose differences between the PB and MC calculations were different from that of 3D CRT. No significant dose differences in critical organs were observed between the two calculations.

PACS number: 87.53.Ly

Heart rate recovery and survival in patients undergoing stereotactic body radiotherapy for treatment of early-stage lung cancer

OBJECTIVES

Up to 25% of patients with stage I non-small cell lung cancer (NSCLC) are considered high-risk for surgery, due to severe medical comorbidity and/or poor pulmonary reserve. Many of these patients are treated with stereotactic body radiotherapy (SBRT). Prognosis in this subgroup of patients is difficult to determine. We investigated the association of impaired heart rate recovery (HRR) with survival in patients who received SBRT for treatment of early-stage lung cancer.

METHODS

We collected data from consecutive patients who, between October 2009 and December 2012, received SBRT for treatment of lung cancer at the Cleveland Clinic, and had 6-minute walk test (6MWT) followed by HRR evaluation performed within six months of initiation of treatment. Impaired HRR was defined as a ≤ 12 beat decrease within the first minute following the 6MWT. Survival analyses were performed using Kaplan-Meier estimates and Cox proportional hazard ratios.

RESULTS

Forty nine patients who received SBRT for treatment of early-stage lung cancer had HRR data available. Thirty two (65%) patients had impaired HRR following the 6MWT. In univariable and multivariable Cox regression analyses, impaired HRR was associated with poorer survival (HR: 11.0, 95% CI: 1.42 - 84.4, p = 0.004, and HR: 15.8, 95% CI: 1.96 - 128.0, p = 0.010, respectively). The 2-year overall survival rates were 52.6% for those with impaired HRR, and 94.1% for those with normal HRR.

CONCLUSION

Impaired HRR was associated with poorer survival in patients who received SBRT for treatment of early-stage lung cancer. HRR following the 6MWT can be one of the factors considered in patient selection for treatment with SBRT, along with other medical comorbidities.

Prediction of survival by [18F]fluorodeoxyglucose positron emission tomography in patients with locally advanced non-small-cell lung cancer undergoing definitive chemoradiation therapy: results of the ACRIN 6668/RTOG 0235 trial

PURPOSE

In this prospective National Cancer Institute-funded American College of Radiology Imaging Network/Radiation Therapy Oncology Group cooperative group trial, we hypothesized that standardized uptake value (SUV) on post-treatment [(18)F]fluorodeoxyglucose positron emission tomography (FDG-PET) correlates with survival in stage III non-small-cell lung cancer (NSCLC).

PATIENTS AND METHODS

Patients received conventional concurrent platinum-based chemoradiotherapy without surgery; postradiotherapy consolidation chemotherapy was allowed. Post-treatment FDG-PET was performed at approximately 14 weeks after radiotherapy. SUVs were analyzed both as peak SUV (SUVpeak) and maximum SUV (SUVmax; both institutional and central review readings), with institutional SUVpeak as the primary end point. Relationships between the continuous and categorical (cutoff) SUVs and survival were analyzed using Cox proportional hazards multivariate models.

RESULTS

Of 250 enrolled patients (226 were evaluable for pretreatment SUV), 173 patients were evaluable for post-treatment SUV analyses. The 2-year survival rate for the entire population was 42.5%. Pretreatment SUVpeak and SUVmax (mean, 10.3 and 13.1, respectively) were not associated with survival. Mean post-treatment SUVpeak and SUVmax were 3.2 and 4.0, respectively. Post-treatment SUVpeak was associated with survival in a continuous variable model (hazard ratio, 1.087; 95% CI, 1.014 to 1.166; P = .020). When analyzed as a prespecified binary value (≤ v > 3.5), there was no association with survival. However, in exploratory analyses, significant results for survival were found using an SUVpeak cutoff of 5.0 (P = .041) or 7.0 (P < .001). All results were similar when SUVmax was used in univariate and multivariate models in place of SUVpeak.

CONCLUSION

Higher post-treatment tumor SUV (SUVpeak or SUVmax) is associated with worse survival in stage III NSCLC, although a clear cutoff value for routine clinical use as a prognostic factor is uncertain at this time.

Dose calculation differences between Monte Carlo and pencil beam depend on the tumor locations and volumes for lung stereotactic body radiation therapy

Stereotactic body radiation therapy (SBRT) has been increasingly used as an efficacious treatment modality for early-stage non-small cell lung cancer. The accuracy of dose calculations is compromised due to the presence of inhomogeneity. For the purpose of a consistent prescription, radiation doses were calculated without heterogeneity correction in several RTOG trials. For patients participating in these trials, recalculations of the planned doses with more accurate dose methods could provide better correlations between the treatment outcomes and the planned doses. Using a Monte Carlo (MC) dose calculation algorithm as a gold standard, we compared the recalculated doses with the MC algorithm to the original pencil beam (PB) calculations for our institutional clinical lung SBRT plans. The focus of this comparison is to investigate the volume and location dependence on the differences between the two dose calculations. Thirty-one clinical plans that followed RTOG and other protocol guidelines were retrospectively investigated in this study. Dosimetric parameters, such as D1, D95, and D99 for the PTV and D1 for organs at risk, were compared between two calculations. Correlations of mean lung dose and V20 of lungs between two calculations were investigated. Significant dependence on tumor size and location was observed from the comparisons between the two dose calculation methods. When comparing the PB calculations without heterogeneity correction to the MC calculations with heterogeneity correction, we found that in terms of D95 of PTV: (1) the two calculations resulted in similar D95 for edge tumors with volumes greater than 25.1 cc; (2) an average overestimation of 5% in PB calculations for edge tumors with volumes less than 25.1 cc; and (3) an average overestimation of 9% or underestimation of 3% in PB calculations for island tumors with volumes smaller or greater than 22.6 cc, respectively. With heterogeneity correction, the PB calculations resulted in an average reduction of 23.8% and 15.3% in the D95 for the PTV for island and edge lesions, respectively, when compared to the MC calculations. For organs at risks, very small differences were found among all the comparisons. Excellent correlations for mean dose and V20 of lungs were observed between the two calculations. This study demonstrated that using a single scaling factor may be overly simplified when accounting for the effects of heterogeneity correction. Accurate dose calculations, such as the Monte Carlo algorithms, are highly recommended to understand dose responses in lung SBRT.

SU-E-T-486: Volume and Location Dependence on the Difference Between Monte Carlo and Pencil Beam Dose Calculations for Lung Stereotactic Body Radiation Therapy

PURPOSE

Stereotactic body radiotherapy has been an efficacious treatment modality for early stage non-small cell lung cancer. The accuracy of dose calculations is in question due to the presence of inhomogeneity. It was required in several clinical trials to calculate dose without heterogeneity correction. However, to better correlate the outcomes with the planned dose, accurate dose calculation with heterogeneity correction is highly desirable.

METHODS

We compared the recalculated dose with Monte Carlo (MC) algorithm to the original Pencil Beam (PB) calculations for clinical lung SBRT plans. Thirty-one clinical plans that followed protocol guidelines were retrospectively investigated. Dosimetric parameters D1, D95 and D99 for the PTV and D1 for organs at risk were compared. Correlations of mean lung dose and V20 of lungs between two calculations were investigated.

RESULTS

Compared to the PB calculations without heterogeneity correction in clinical plans, we found that in terms of D95 of PTV, (1) the two calculations resulted in similar D95 for edge tumors with volumes greater than 25.1cc; (2) an average overestimation of 5% in PB calculations for edge tumors with volumes less than 25.1cc; and (3) an average overestimation of 9% or underestimation of 3% in PB calculations for island tumors with volumes smaller or greater than 22.6 cc, respectively. With heterogeneity correction, the PB calculation resulted in an average reduction of 23.8% and 15.3% in D95 for island and edge lesions respectively compared to the MC calculation. For organs at risks, no clinical meaningful differences were found among all the comparisons. Excellent correlations for mean dose and V20 of lungs were observed between the two calculations.

CONCLUSIONS

Using a single scaling factor to account for the differences in using heterogeneity correction may not be sufficient. To understand dose-response relation in Lung SBRT, accurate dose calculation such as the Monte Carlo algorithms is highly recommended.

Stereotactic body radiation therapy for inoperable early stage lung cancer

CONTEXT

Patients with early stage but medically inoperable lung cancer have a poor rate of primary tumor control (30%-40%) and a high rate of mortality (3-year survival, 20%-35%) with current management.

OBJECTIVE

To evaluate the toxicity and efficacy of stereotactic body radiation therapy in a high-risk population of patients with early stage but medically inoperable lung cancer.

DESIGN, SETTING, AND PATIENTS

Phase 2 North American multicenter study of patients aged 18 years or older with biopsy-proven peripheral T1-T2N0M0 non-small cell tumors (measuring <5 cm in diameter) and medical conditions precluding surgical treatment. The prescription dose was 18 Gy per fraction x 3 fractions (54 Gy total) with entire treatment lasting between 1(1/2) and 2 weeks. The study opened May 26, 2004, and closed October 13, 2006; data were analyzed through August 31, 2009.

MAIN OUTCOME MEASURES

The primary end point was 2-year actuarial primary tumor control; secondary end points were disease-free survival (ie, primary tumor, involved lobe, regional, and disseminated recurrence), treatment-related toxicity, and overall survival.

RESULTS

A total of 59 patients accrued, of which 55 were evaluable (44 patients with T1 tumors and 11 patients with T2 tumors) with a median follow-up of 34.4 months (range, 4.8-49.9 months). Only 1 patient had a primary tumor failure; the estimated 3-year primary tumor control rate was 97.6% (95% confidence interval [CI], 84.3%-99.7%). Three patients had recurrence within the involved lobe; the 3-year primary tumor and involved lobe (local) control rate was 90.6% (95% CI, 76.0%-96.5%). Two patients experienced regional failure; the local-regional control rate was 87.2% (95% CI, 71.0%-94.7%). Eleven patients experienced disseminated recurrence; the 3-year rate of disseminated failure was 22.1% (95% CI, 12.3%-37.8%). The rates for disease-free survival and overall survival at 3 years were 48.3% (95% CI, 34.4%-60.8%) and 55.8% (95% CI, 41.6%-67.9%), respectively. The median overall survival was 48.1 months (95% CI, 29.6 months to not reached). Protocol-specified treatment-related grade 3 adverse events were reported in 7 patients (12.7%; 95% CI, 9.6%-15.8%); grade 4 adverse events were reported in 2 patients (3.6%; 95% CI, 2.7%-4.5%). No grade 5 adverse events were reported.

CONCLUSION

Patients with inoperable non-small cell lung cancer who received stereotactic body radiation therapy had a survival rate of 55.8% at 3 years, high rates of local tumor control, and moderate treatment-related morbidity.