Long-Term Prospective Outcomes of Intensity Modulated Radiotherapy for Locally Advanced Lung Cancer: A Secondary Analysis of a Randomized Clinical Trial.

Importance: The optimal radiotherapy technique for unresectable locally advanced non-small cell lung cancer (NSCLC) is controversial, so evaluating long-term prospective outcomes of intensity-modulated radiotherapy (IMRT) is important. Objective: To compare long-term prospective outcomes of patients receiving IMRT and 3-dimensional conformal radiotherapy (3D-CRT) with concurrent carboplatin/paclitaxel for locally advanced NSCLC. Design, Setting, and Participants: A secondary analysis of a prospective phase 3 randomized clinical trial NRG Oncology-RTOG 0617 assessed 483 patients receiving chemoradiotherapy (3D-CRT vs IMRT) for locally advanced NSCLC based on stratification. Main Outcomes and Measures: Long-term outcomes were analyzed, including overall survival (OS), progression-free survival (PFS), time to local failure, development of second cancers, and severe grade 3 or higher adverse events (AEs) per Common Terminology Criteria for Adverse Events, version 3. The percentage of an organ volume (V) receiving a specified amount of radiation in units of Gy is reported as V(radiation dose). Results: Of 483 patients (median [IQR] age, 64 [57-70] years; 194 [40.2%] female), 228 (47.2%) received IMRT, and 255 (52.8%) received 3D-CRT (median [IQR] follow-up, 5.2 [4.8-6.0] years). IMRT was associated with a 2-fold reduction in grade 3 or higher pneumonitis AEs compared with 3D-CRT (8 [3.5%] vs 21 [8.2%]; P = .03). On univariate analysis, heart V20, V40, and V60 were associated with worse OS (hazard ratios, 1.06 [95% CI, 1.04-1.09]; 1.09 [95% CI, 1.05-1.13]; 1.16 [95% CI, 1.09-1.24], respectively; all P < .001). IMRT significantly reduced heart V40 compared to 3D-CRT (16.5% vs 20.5%; P < .001). Heart V40 (<20%) had better OS than V40 (≥20%) (median [IQR], 2.5 [2.1-3.1] years vs 1.7 [1.5-2.0] years; P < .001). On multivariable analysis, heart V40 (≥20%), was associated with worse OS (hazard ratio, 1.34 [95% CI, 1.06-1.70]; P = .01), whereas lung V5 and age had no association with OS. Patients receiving IMRT and 3D-CRT had similar rates of developing secondary cancers (15 [6.6%] vs 14 [5.5%]) with long-term follow-up. Conclusions and Relevance: These findings support the standard use of IMRT for locally advanced NSCLC. IMRT should aim to minimize lung V20 and heart V20 to V60, rather than constraining low-dose radiation bath. Lung V5 and age were not associated with survival and should not be considered a contraindication for chemoradiotherapy. Trial Registration: ClinicalTrials.gov Identifier: NCT00533949.

Association of Radiotherapy Duration With Clinical Outcomes in Patients With Esophageal Cancer Treated in NRG Oncology Trials: A Secondary Analysis of NRG Oncology Randomized Clinical Trials.

Importance: For many types of epithelial malignant neoplasms that are treated with definitive radiotherapy (RT), treatment prolongation and interruptions have an adverse effect on outcomes. Objective: To analyze the association between RT duration and outcomes in patients with esophageal cancer who were treated with definitive chemoradiotherapy (CRT). Design, Setting, and Participants: This study was an unplanned, post hoc secondary analysis of 3 prospective, multi-institutional phase 3 randomized clinical trials (Radiation Therapy Oncology Group [RTOG] 8501, RTOG 9405, and RTOG 0436) of the National Cancer Institute-sponsored NRG Oncology (formerly the National Surgical Adjuvant Breast and Bowel Project, RTOG, and Gynecologic Oncology Group). Enrolled patients with nonmetastatic esophageal cancer underwent definitive CRT in the trials between 1986 and 2013, with follow-up occurring through 2014. Data analyses were conducted between March 2022 to February 2023. Exposures: Treatment groups in the trials used standard-dose RT (50 Gy) and concurrent chemotherapy. Main Outcomes and Measures: The outcomes were local-regional failure (LRF), distant failure, disease-free survival (DFS), and overall survival (OS). Multivariable models were used to examine the associations between these outcomes and both RT duration and interruptions. Radiotherapy duration was analyzed as a dichotomized variable using an X-Tile software to choose a cut point and its median value as a cut point, as well as a continuous variable. Results: The analysis included 509 patients (median [IQR] age, 64 [57-70] years; 418 males [82%]; and 376 White individuals [74%]). The median (IQR) follow-up was 4.01 (2.93-4.92) years for surviving patients. The median cut point of RT duration was 39 days or less in 271 patients (53%) vs more than 39 days in 238 patients (47%), and the X-Tile software cut point was 45 days or less in 446 patients (88%) vs more than 45 days in 63 patients (12%). Radiotherapy interruptions occurred in 207 patients (41%). Female (vs male) sex and other (vs White) race and ethnicity were associated with longer RT duration and RT interruptions. In the multivariable models, RT duration longer than 45 days was associated with inferior DFS (hazard ratio [HR], 1.34; 95% CI, 1.01-1.77; P = .04). The HR for OS was 1.33, but the results were not statistically significant (95% CI, 0.99-1.77; P = .05). Radiotherapy duration longer than 39 days (vs ≤39 days) was associated with a higher risk of LRF (HR, 1.32; 95% CI, 1.06-1.65; P = .01). As a continuous variable, RT duration (per 1 week increase) was associated with DFS failure (HR, 1.14; 95% CI, 1.01-1.28; P = .03). The HR for LRF 1.13, but the result was not statistically significant (95% CI, 0.99-1.28; P = .07). Conclusions and Relevance: Results of this study indicated that in patients with esophageal cancer receiving definitive CRT, prolonged RT duration was associated with inferior outcomes; female patients and those with other (vs White) race and ethnicity were more likely to have longer RT duration and experience RT interruptions. Radiotherapy interruptions should be minimized to optimize outcomes.

Randomized Phase IIB Trial of Proton Beam Therapy Versus Intensity-Modulated Radiation Therapy for Locally Advanced Esophageal Cancer.

PURPOSE: Whether dosimetric advantages of proton beam therapy (PBT) translate to improved clinical outcomes compared with intensity-modulated radiation therapy (IMRT) remains unclear. This randomized trial compared total toxicity burden (TTB) and progression-free survival (PFS) between these modalities for esophageal cancer. METHODS: This phase IIB trial randomly assigned patients to PBT or IMRT (50.4 Gy), stratified for histology, resectability, induction chemotherapy, and stage. The prespecified coprimary end points were TTB and PFS. TTB, a composite score of 11 distinct adverse events (AEs), including common toxicities as well as postoperative complications (POCs) in operated patients, quantified the extent of AE severity experienced over the duration of 1 year following treatment. The trial was conducted using Bayesian group sequential design with three planned interim analyses at 33%, 50%, and 67% of expected accrual (adjusted for follow-up). RESULTS: This trial (commenced April 2012) was approved for closure and analysis upon activation of NRG-GI006 in March 2019, which occurred immediately prior to the planned 67% interim analysis. Altogether, 145 patients were randomly assigned (72 IMRT, 73 PBT), and 107 patients (61 IMRT, 46 PBT) were evaluable. Median follow-up was 44.1 months. Fifty-one patients (30 IMRT, 21 PBT) underwent esophagectomy; 80% of PBT was passive scattering. The posterior mean TTB was 2.3 times higher for IMRT (39.9; 95% highest posterior density interval, 26.2-54.9) than PBT (17.4; 10.5-25.0). The mean POC score was 7.6 times higher for IMRT (19.1; 7.3-32.3) versus PBT (2.5; 0.3-5.2). The posterior probability that mean TTB was lower for PBT compared with IMRT was 0.9989, which exceeded the trial's stopping boundary of 0.9942 at the 67% interim analysis. The 3-year PFS rate (50.8% v 51.2%) and 3-year overall survival rates (44.5% v 44.5%) were similar. CONCLUSION: For locally advanced esophageal cancer, PBT reduced the risk and severity of AEs compared with IMRT while maintaining similar PFS.

Metabolic Responses to Metformin in Inoperable Early-stage Non-Small Cell Lung Cancer Treated With Stereotactic Radiotherapy: Results of a Randomized Phase II Clinical Trial.

BACKGROUND: Metformin reduces glucose uptake in physiologic tissues and has been shown to affect non-small cell lung cancer (NSCLC) metabolism. We hypothesized that positron emission tomography (PET) scans could detect the impact of metformin on glucose uptake in NSCLC and we sought to test this hypothesis in a prospective clinical trial. MATERIALS AND METHODS: A single-blinded phase II clinical trial was performed with subjects randomized 6:1 to 3 to 4 weeks of metformin versus placebo for inoperable early-stage NSCLC. PET scans were performed at baseline, mid-treatment (after 2 wk study medication), and 6 months postradiation. The primary endpoint of the trial was tumor metabolic response to metformin by PERCIST before definitive radiation. Stereotactic body radiotherapy to 50 Gy in 4 fractions was used for peripheral tumors and 70 Gy in 10 fractions for central tumors. RESULTS: There were 14 subjects randomized to the metformin and 1 to placebo. Histologies were 60% adenocarcinoma, 33.3% squamous cell carcinoma, and 6.7% poorly differentiated carcinoma. At mid-treatment PET scan, 57% of subjects randomized to metformin met PERCIST criteria for metabolic response, of which 75% had progressive metabolic disease and 25% had partial metabolic response, whereas the placebo subject had stable metabolic disease. At 6 months, the metformin arm had 69% complete metabolic response, 23% partial metabolic response and 1 progressive metabolic disease, and the subject treated with placebo had a complete metabolic response. There were no CTCAE grade ≥3 toxicities. CONCLUSIONS: Despite low accrual, majority of subjects treated with metformin had metabolic responses by PERCIST criteria on PET imaging. Contrary to the effect of metformin on most physiologic tissues, most tumors had increased metabolic activity in response to metformin.

Anticancer therapy and lung injury: molecular mechanisms.

INTRODUCTION: Chemotherapy and radiation therapy are two mainstream strategies applied in the treatment of cancer that is not operable. Patients with hematological or solid tumor malignancies substantially benefit from chemotherapeutic drugs and/or ionizing radiation delivered to the site of malignancy. However, considerable adverse effects, including lung inflammation and fibrosis, are associated with the use of these treatment modalities. Areas covered: As we move toward the era of precision health, we are compelled to understand the molecular basis of chemoradiation-induced pathological lung remodeling and to develop effective treatment strategies that mitigate the development of chronic lung disease (i.e. fibrosis) in cancer patients. The review discusses chemotherapeutic agents that are reported to induce or associate with acute and/or chronic lung injury. Expert commentary: There is a need to molecularly understand how chemotherapeutic drugs induce or associate with respiratory toxicities and whether such characteristics are inherently related to their antitumor effect or are collateral. Once such mechanisms have been identified and/or fully characterized, they may be able to guide disease-management decisions including effective intervention strategies for the adverse effects. In the meantime, radiation oncologists should be judicious on the dose of radiation delivered to the lungs, the volume of lung irradiated, and concurrent use of chemotherapeutic drugs.

Barriers to Combined-Modality Therapy for Limited-Stage Small Cell Lung Cancer.

Importance: Combined-modality therapy with chemotherapy and radiation therapy plays a crucial role in the upfront treatment of patients with limited-stage small cell lung cancer (SCLC), but there may be barriers to utilization in the United States. Objective: To estimate utilization rates and factors associated with chemotherapy and radiation therapy delivery for limited-stage SCLC using the National Cancer Database. Design, Setting, and Participants: Analysis of initial management of all limited-stage SCLC cases from 2004 through 2013 in the National Cancer Database. Main Outcomes and Measures: Utilization rates of chemotherapy and radiation therapy at time of initial treatment. Multivariable analysis identified independent clinical and socioeconomic factors associated with utilization and overall survival. Results: A total of 70 247 cases met inclusion criteria (55.3% female; median age, 68 y [range, 19-90 y]). Initial treatment was 55.5% chemotherapy and radiation therapy, 20.5% chemotherapy alone, 3.5% radiation therapy alone, and 20.0% neither (0.5% not reported). Median survival was 18.2 (95% CI, 17.9-18.4), 10.5 (95% CI, 10.3-10.7), 8.3 (95% CI, 7.7-8.8), and 3.7 (95% CI, 3.5-3.8) months, respectively. Being uninsured was associated with a lower likelihood of both chemotherapy (odds ratio [OR], 0.65; 95% CI, 0.56-0.75; P < .001) and radiation therapy (OR, 0.75; 95% CI, 0.67-0.85; P < .001) administration on multivariable analysis. Medicare/Medicaid insurance had no impact on chemotherapy use, whereas Medicaid (OR, 0.79; 95% CI, 0.72-0.87; P < .001) and Medicare (OR, 0.86; 95% CI, 0.82-0.91; P < .001) were independently associated with a lower likelihood of radiation therapy delivery. Lack of health insurance (HR, 1.19; 95% CI, 1.13-1.26; P < .001), Medicaid (HR, 1.27; 95% CI, 1.21-1.32; P < .001), and Medicare (HR, 1.12; 95% CI, 1.09-1.15; P < .001) coverage were independently associated with shorter survival on adjusted analysis, while chemotherapy (HR, 0.55; 95% CI, 0.54-0.57; P < .001) and radiation therapy (HR, 0.62; 95% CI, 0.60-0.63; P < .001) were associated with a survival benefit. Conclusions and Relevance: Substantial proportions of patients documented in a major US cancer registry did not receive radiation therapy or chemotherapy as part of initial treatment for limited-stage SCLC, which, in turn, was associated with poor survival. Lack of radiation therapy delivery was uniquely associated with government insurance coverage, suggesting a need for targeted access improvement in this population. Additional work will be necessary to conclusively define exact population patterns, specific treatment deficiencies, and causative factors leading to heterogeneous care delivery.

Prophylactic Cranial Irradiation Following Surgical Resection of Early-Stage Small-Cell Lung Cancer: A Review of the Literature.

With increasing use of low-dose screening CT scans, the diagnosis of early-stage small-cell lung cancer (SCLC) without evidence of mediastinal nodal or distant metastasis is likely to become more common, but the role of adjuvant therapies such as prophylactic cranial irradiation (PCI) are not well understood in this population. We performed a review of the literature pertaining to the impact of PCI in patients who underwent surgical resection of early-stage SCLC. Four studies were identified that were pertinent including three single-institution retrospective analyses and a National Cancer Database analysis. Based upon these studies, we estimate the rate of brain metastases to be 10-15% for Stage I and 15-25% for Stage II disease without PCI. However, the impact of PCI on the development of brain metastases and its ultimate impact on overall survival were not consistent across these studies. In summary, there is sparse evidence to guide recommendations for PCI following resection of early-stage SCLC. While it may be reasonable to offer PCI to maximize likelihood of cure, alternative strategies such as observation with close imaging follow-up can also be considered for the appropriate patient given the known neurocognitive side effects of PCI.

7-year follow-up after stereotactic ablative radiotherapy for patients with stage I non-small cell lung cancer: Results of a phase 2 clinical trial.

BACKGROUND: The authors evaluated the efficacy, patterns of failure, and toxicity of stereotactic ablative radiotherapy (SABR) for patients with medically inoperable, clinical stage I non-small cell lung cancer (NSCLC) in a prospective clinical trial with 7 years of follow-up. Clinical staging was performed according to the seventh edition of the American Joint Committee on Cancer TNM staging system. METHODS: Eligible patients with histologically confirmed NSCLC of clinical stage I as determined using positron emission tomography staging were treated with SABR (50 grays in 4 fractions). The primary endpoint was progression-free survival. Patients were followed with computed tomography and/or positron emission tomography/computed tomography every 3 months for the first 2 years, every 6 months for the next 3 years, and then annually thereafter. RESULTS: A total of 65 patients were eligible for analysis. The median age of the patients was 71 years, and the median follow-up was 7.2 years. A total of 18 patients (27.7%) developed disease recurrence at a median of 14.5 months (range, 4.3-71.5 months) after SABR. Estimated incidences of local, regional, and distant disease recurrence using competing risk analysis were 8.1%, 10.9%, and 11.0%, respectively, at 5 years and 8.1%, 13.6%, and 13.8%, respectively, at 7 years. A second primary lung carcinoma developed in 12 patients (18.5%) at a median of 35 months (range, 5-67 months) after SABR. Estimated 5-year and 7-year progression-free survival rates were 49.5% and 38.2%, respectively; the corresponding overall survival rates were 55.7% and 47.5%, respectively. Three patients (4.6%) experienced grade 3 treatment-related adverse events. No patients developed grade 4 or 5 adverse events (toxicity was graded according to the National Cancer Institute Common Terminology Criteria for Adverse Events [version 3.0]). CONCLUSIONS: With long-term follow-up, the results of the current prospective study demonstrated outstanding local control and low toxicity after SABR in patients with clinical stage I NSCLC. Regional disease recurrence and distant metastases were the dominant manifestations of failure. Surveillance for second primary lung carcinoma is recommended. Cancer 2017;123:3031-39. © 2017 American Cancer Society.

Final Results of NRG Oncology RTOG 0246: An Organ-Preserving Selective Resection Strategy in Esophageal Cancer Patients Treated with Definitive Chemoradiation.

INTRODUCTION: The impact of selective surgical resection for patients with esophageal cancer treated with definitive chemoradiation has not been clearly evaluated long-term. METHODS: NRG (National Surgical Adjuvant Breast and Bowel Project, Radiation Therapy Oncology Group, Gynecologic Oncology Group) Oncology Radiation Therapy Oncology Group 0246 was a multi-institutional, single-arm, open-label, nonrandomized phase II study that enrolled 43 patients from September 2003 to March 2008 with clinical stage T1-4N0-1M0 squamous cell or adenocarcinoma of the esophagus or gastroesophageal junction from 19 sites. Patients received induction chemotherapy with fluorouracil (650 mg/m2/d), cisplatin (15 mg/m2/d), and paclitaxel (200 mg/m2/d) for two cycles followed by concurrent chemoradiation consisting of 50.4 Gy of radiation (1.8 Gy per fraction) and daily fluorouracil (300 mg/m2/d) with cisplatin (15 mg/m2/d) over the first 5 days. After definitive chemoradiation, patients were evaluated for residual disease. Selective esophagectomy was considered only for patients with residual disease after chemoradiation (clinical incomplete response) or recurrent disease on surveillance. RESULTS: This report looks at the long-term outcome of this selective surgical strategy. With a median follow-up of 8.1 years (minimum to maximum for 12 alive patients 7.2-9.8 years), the estimated 5- and 7-year survival rates are 36.6% (95% confidence interval [CI]: 22.3-51.0) and 31.7% (95% CI: 18.3-46.0). Clinical complete response was achieved in 15 patients (37%), with 5- and 7-yearr survival rates of 53.3% (95% CI: 26.3-74.4) and 46.7% (95% CI: 21.2-68.7). Esophageal resection was not required in 20 of 41 patients (49%) on this trial. CONCLUSIONS: The long-term results of NRG Oncology Radiation Therapy Oncology Group 0246 demonstrate promising efficacy of a selective surgical resection strategy and suggest the need for larger randomized studies to further evaluate this organ-preserving approach.

Local Control and Toxicity of a Simultaneous Integrated Boost for Dose Escalation in Locally Advanced Esophageal Cancer: Interim Results from a Prospective Phase I/II Trial.

INTRODUCTION: Approximately 50% of recurrences after standard-dose chemoradiation for locally advanced esophageal cancer occur within the gross tumor volume (GTV). In this prospective phase I/II clinical trial, we explored the use of a simultaneous integrated boost (SIB) dose to the GTV. METHODS: Forty-four patients with unresectable esophageal cancer received chemoradiation with an SIB of 58.8 to 63 Gy to the GTV and 50.4 Gy to the planning target volume, all in 28 fractions, with 5 weeks of concurrent docetaxel and fluorouracil or capecitabine. The end points were maximum tolerated dose, time to local failure, and clinical response. RESULTS: Excluding those with less than 6 months of follow-up, 38 patients were evaluated at the time of analysis. The median age was 65 years (range 37-84). Most patients (71%) were men; 84% had T3 disease, 37% had N1 disease, 26% had N2 disease, 13% had M1 disease, and 50% had adenocarcinoma. The maximum tolerated SIB dose was 63 Gy. None experienced Common Terminology Criteria for Adverse Events grade 4 or 5 toxicity. At a median follow-up time of 13.3 months (range 1.2-36.2), 11 (29%) had local failure (median time to local failure 2.5 months [range 1.5-23.9]). A comparison with 97 similar patients who received 50.4 Gy without an SIB showed that the SIB reduced the local failure rate for patients with node-positive disease (13% versus 56%, p = 0.04), adenocarcinoma (26% versus 59%, p = 0.02), or stage III-IV disease (29% versus 55%, p = 0.04). CONCLUSIONS: SIB intensity-modulated radiation therapy to gross primary disease may improve local control for patients with unresectable locally advanced esophageal cancer, especially those with adenocarcinoma.

Impact of Intensity-Modulated Radiation Therapy Technique for Locally Advanced Non-Small-Cell Lung Cancer: A Secondary Analysis of the NRG Oncology RTOG 0617 Randomized Clinical Trial.

Purpose Although intensity-modulated radiation therapy (IMRT) is increasingly used to treat locally advanced non-small-cell lung cancer (NSCLC), IMRT and three-dimensional conformal external beam radiation therapy (3D-CRT) have not been compared prospectively. This study compares 3D-CRT and IMRT outcomes for locally advanced NSCLC in a large prospective clinical trial. Patients and Methods A secondary analysis was performed to compare IMRT with 3D-CRT in NRG Oncology clinical trial RTOG 0617, in which patients received concurrent chemotherapy of carboplatin and paclitaxel with or without cetuximab, and 60- versus 74-Gy radiation doses. Comparisons included 2-year overall survival (OS), progression-free survival, local failure, distant metastasis, and selected Common Terminology Criteria for Adverse Events (version 3) ≥ grade 3 toxicities. Results The median follow-up was 21.3 months. Of 482 patients, 53% were treated with 3D-CRT and 47% with IMRT. The IMRT group had larger planning treatment volumes (median, 427 v 486 mL; P = .005); a larger planning treatment volume/volume of lung ratio (median, 0.13 v 0.15; P = .013); and more stage IIIB disease (30.3% v 38.6%, P = .056). Two-year OS, progression-free survival, local failure, and distant metastasis-free survival were not different between IMRT and 3D-CRT. IMRT was associated with less ≥ grade 3 pneumonitis (7.9% v 3.5%, P = .039) and a reduced risk in adjusted analyses (odds ratio, 0.41; 95% CI, 0.171 to 0.986; P = .046). IMRT also produced lower heart doses ( P < .05), and the volume of heart receiving 40 Gy (V40) was significantly associated with OS on adjusted analysis ( P < .05). The lung V5 was not associated with any ≥ grade 3 toxicity, whereas the lung V20 was associated with increased ≥ grade 3 pneumonitis risk on multivariable analysis ( P = .026). Conclusion IMRT was associated with lower rates of severe pneumonitis and cardiac doses in NRG Oncology clinical trial RTOG 0617, which supports routine use of IMRT for locally advanced NSCLC.

Strategies for combining immunotherapy with radiation for anticancer therapy.

Radiation therapy controls local disease but also prompts the release of tumor-associated antigens and stress-related danger signals that primes T cells to promote tumor regression at unirradiated sites known as the abscopal effect. This may be enhanced by blocking inhibitory immune signals that modulate immune activity through a variety of mechanisms. Indeed, abscopal responses have occurred in patients with lung cancer or melanoma when given anti-CTLA4 antibody and radiation. Other approaches involve expanding and reinfusing T or NK cells or engineered T cells to express receptors that target specific tumor peptides. These approaches may be useful for immunocompromised patients receiving radiation. Preclinical and clinical studies are testing both immune checkpoint-based strategies and adoptive immunotherapies with radiation.

Post-chemoradiation surgical pathology stage can customize the surveillance strategy in patients with esophageal adenocarcinoma.

Current algorithms for surveillance of patients with esophageal adenocarcinoma (EAC) after chemoradiation and surgery (trimodality therapy [TMT]) remain empiric. The authors hypothesized that the frequency, type, and timing of relapses after TMT would be highly associated with surgical pathology stage (SPS), and therefore SPS could be used to individualize the surveillance strategy. Between 2000 and 2010, 518 patients with EAC were identified who underwent TMT at The University of Texas MD Anderson Cancer Center and were frequently surveyed. Frequency, type, and timing of the first relapse (locoregional and/or distant) were tabulated according to SPS. Standard statistical approaches were used. The median follow-up time after esophageal surgery was 55.4 months (range, 1.0-149.2 months). Disease relapse occurred in 215 patients (41.5%). Higher SPS was associated with a higher rate of relapse (0/I vs II/III, P≤.001; 0/I vs II, P=.002; SPS 0/I vs III, P≤.001; and SPS II vs III, P=.005) and with shorter time to relapse (P<.001). Irrespective of the SPS, approximately 95% of all relapses occurred within 36 months of surgery. The 3- and 5-year overall survival rates were shorter for patients with a higher SPS than those with a lower SPS (0/I vs II/III, P≤.001; 0/I vs II, P≤.001; 0/I vs III, P≤.001; and II vs III, P=.014). The compelling data show an excellent association between SPS and frequency/type/timing of relapses after TMT in patients with EAC. Thus, the surveillance strategy can potentially be customized based on SPS. These data can inform a future evidence-based surveillance strategy that can be efficient and cost-effective.

Progress in the management of limited-stage small cell lung cancer.

Approximately 15% of lung cancer cases are of the small cell subtype, but this variant is highly aggressive and is often diagnosed at advanced stages. Outcomes after current treatment regimens have been poor, with 5-year survival rates as low as 25% for patients with limited-stage disease. Advances in therapy for small cell lung cancer have included the development of more effective chemotherapeutic agents and radiation techniques. For example, hyperfractionated radiotherapy given early in the course of the disease can reduce local recurrence and extend survival. Other technologic advances in radiation planning and delivery such as intensity-modulated radiotherapy, image-guided adaptive radiotherapy, and 4-dimensional computed tomography/positron emission tomography have facilitated the design of treatment volumes that closely conform to the shape of the tumor, which allows higher radiation doses to be given while minimizing radiation-induced toxicity to adjacent structures. Future improvements in outcomes will require clarifying the molecular basis for this disease.

Surgery is an essential component of multimodality therapy for patients with locally advanced esophageal adenocarcinoma.

BACKGROUND: Experience with neoadjuvant chemoradiation (CXRT) has raised questions regarding the additional benefit of surgery after locally advanced esophageal adenocarcinoma patients achieve a clinical response to CXRT. We sought to quantify the value of surgery by comparing the overall (OS) and disease-free survival (DFS) of trimodality-eligible patients treated with definitive CXRT vs. CXRT followed by esophagectomy. METHODS: We identified 143 clinical stage III esophageal adenocarcinoma patients that were eligible for trimodality therapy. All patients successfully completed neoadjuvant CXRT and were considered appropriate candidates for resection. Patients that were medically inoperable were excluded. Cox regression models were used to identify significant predictors of survival. RESULTS: Among the 143 patients eligible for surgery after completing CXRT, 114 underwent resection and 29 did not. Poorly differentiated tumors (HR = 2.041, 95% CI = 1.235-3.373) and surgical resection (HR = 0.504, 95% CI = 0.283-0.899) were the only independent predictors of OS. Patients treated with surgery had a 50 and 54 % risk reduction in overall and cancer-specific mortality, respectively. Median OS (41.2 vs. 20.3 months, p = 0.012) and DFS (21.5 vs. 11.4 months, p = 0.007) were significantly improved with the addition of surgery compared to definitive CXRT. CONCLUSIONS: Surgery provides a significant survival benefit to trimodality-eligible esophageal adenocarcinoma patients with locally advanced disease.

Modulation of c-Met signaling and cellular sensitivity to radiation: potential implications for therapy.

The c-Met/hepatocyte growth factor receptor and its family members are known to promote cancer cell migration and invasion. Signaling within and beyond this pathway contributes to the systemic spread of metastases through induction of the epithelial-mesenchymal transition, a process also implicated in mediating resistance to current anticancer therapies, including radiation. Induction of c-Met has also been observed after irradiation, suggesting that c-Met participates in radiation-induced disease progression through the epithelial-mesenchymal transition. Therefore, c-Met inhibition is an attractive target for potentially mitigating radiation resistance. This article summarizes key findings regarding crosstalk between radiotherapy and c-Met and discusses studies performed to date in which c-Met inhibition was used as a strategy to increase cellular radiosensitivity.

A Phase II study of a paclitaxel-based chemoradiation regimen with selective surgical salvage for resectable locoregionally advanced esophageal cancer: initial reporting of RTOG 0246.

PURPOSE: The strategy of definitive chemoradiation with selective surgical salvage in locoregionally advanced esophageal cancer was evaluated in a Phase II trial in Radiation Therapy Oncology Group (RTOG)-affiliated sites. METHODS AND MATERIALS: The study was designed to detect an improvement in 1-year survival from 60% to 77.5% (α = 0.05; power = 80%). Definitive chemoradiation involved induction chemotherapy with 5-fluorouracil (5-FU) (650 mg/mg(2)/day), cisplatin (15 mg/mg(2)/day), and paclitaxel (200 mg/mg(2)/day) for two cycles, followed by concurrent chemoradiation with 50.4 Gy (1.8 Gy/fraction) and daily 5-FU (300 mg/mg(2)/day) with cisplatin (15 mg/mg(2)/day) over the first 5 days. Salvage surgical resection was considered for patients with residual or recurrent esophageal cancer who did not have systemic disease. RESULTS: Forty-three patients with nonmetastatic resectable esophageal cancer were entered from Sept 2003 to March 2006. Forty-one patients were eligible for analysis. Clinical stage was ≥T3 in 31 patients (76%) and N1 in 29 patients (71%), with adenocarcinoma histology in 30 patients (73%). Thirty-seven patients (90%) completed induction chemotherapy followed by concurrent chemoradiation. Twenty-eight patients (68%) experienced Grade 3+ nonhematologic toxicity. Four treatment-related deaths were noted. Twenty-one patients underwent surgery following definitive chemoradiation because of residual (17 patients) or recurrent (3 patients) esophageal cancer,and 1 patient because of choice. Median follow-up of live patients was 22 months, with an estimated 1-year survival of 71%. CONCLUSIONS: In this Phase II trial (RTOG 0246) evaluating selective surgical salvage after definitive chemoradiation in locoregionally advanced esophageal cancer, the hypothesized 1-year RTOG survival rate (77.5%) was not achieved (1 year, 71%; 95% confidence interval< 54%-82%).

Consideration of dose limits for organs at risk of thoracic radiotherapy: atlas for lung, proximal bronchial tree, esophagus, spinal cord, ribs, and brachial plexus.

PURPOSE: To review the dose limits and standardize the three-dimenional (3D) radiographic definition for the organs at risk (OARs) for thoracic radiotherapy (RT), including the lung, proximal bronchial tree, esophagus, spinal cord, ribs, and brachial plexus. METHODS AND MATERIALS: The present study was performed by representatives from the Radiation Therapy Oncology Group, European Organization for Research and Treatment of Cancer, and Soutwestern Oncology Group lung cancer committees. The dosimetric constraints of major multicenter trials of 3D-conformal RT and stereotactic body RT were reviewed and the challenges of 3D delineation of these OARs described. Using knowledge of the human anatomy and 3D radiographic correlation, draft atlases were generated by a radiation oncologist, medical physicist, dosimetrist, and radiologist from the United States and reviewed by a radiation oncologist and medical physicist from Europe. The atlases were then critically reviewed, discussed, and edited by another 10 radiation oncologists. RESULTS: Three-dimensional descriptions of the lung, proximal bronchial tree, esophagus, spinal cord, ribs, and brachial plexus are presented. Two computed tomography atlases were developed: one for the middle and lower thoracic OARs (except for the heart) and one focusing on the brachial plexus for a patient positioned supine with their arms up for thoracic RT. The dosimetric limits of the key OARs are discussed. CONCLUSIONS: We believe these atlases will allow us to define OARs with less variation and generate dosimetric data in a more consistent manner. This could help us study the effect of radiation on these OARs and guide high-quality clinical trials and individualized practice in 3D-conformal RT and stereotactic body RT.

ACR appropriateness criteria on nonsurgical treatment for non-small-cell lung cancer: poor performance status or palliative intent.

Radiation therapy (RT) plays a major role in the definitive treatment of patients with non-small-cell lung cancer who are unable to tolerate surgery. Radiation therapy alone is used primarily for early-stage (stages I and II) patients. Higher doses of RT (>65 Gy) seem to improve outcomes, and modern techniques such as stereotactic body RT have been very promising. For patients with locally advanced disease (stages IIIA and IIIB), concurrent chemotherapy and RT remains the standard of care. However, many patients cannot tolerate the regimen because of its toxicity. Sequential chemotherapy followed by RT is used in these situations. Radiation therapy alone is used for the rare patient who cannot tolerate the use of any chemotherapy because of comorbid conditions. Palliative external-beam RT is useful for patients with metastatic disease, causing symptoms such as dyspnea, cough, hemoptysis, postobstructive pneumonia, and pain. Hypofractionation has been attempted as a means to provide more rapid and convenient symptom relief, but results from clinical trials are conflicting on whether it is an improvement over standard palliative fractionation. Endobronchial brachytherapy provides relief for patients with endobronchial lesions causing obstruction or hemoptysis. Palliative chemotherapy improves survival and quality of life in patients with metastatic disease compared with best supportive care. Chemotherapy also improves outcomes as a second-line and third-line treatment for patients in whom previous regimens have failed. Biologic therapies such as erlotinib and bevacizumab have been incorporated into every phase of chemotherapy with good results.