Daniel R. Gomez

Comparative Effectiveness of 5 Treatment Strategies for Early-Stage Non-Small Cell Lung Cancer in the Elderly

PURPOSE The incidence of early-stage non-small cell lung cancer (NSCLC) among older adults is expected to increase because of demographic trends and computed tomography-based screening; yet, optimal treatment in the elderly remains controversial. Using the Surveillance, Epidemiology, and End Results (SEER)-Medicare cohort spanning 2001-2007, we compared survival outcomes associated with 5 strategies used in contemporary practice: lobectomy, sublobar resection, conventional radiation therapy, stereotactic ablative radiation therapy (SABR), and observation. METHODS AND MATERIALS Treatment strategy and covariates were determined in 10,923 patients aged ≥ 66 years with stage IA-IB NSCLC. Cox regression, adjusted for patient and tumor factors, compared overall and disease-specific survival for the 5 strategies. In a second exploratory analysis, propensity-score matching was used for comparison of SABR with other options. RESULTS The median age was 75 years, and 29% had moderate to severe comorbidities. Treatment distribution was lobectomy (59%), sublobar resection (11.7%), conventional radiation (14.8%), observation (12.6%), and SABR (1.1%). In Cox regression analysis with a median follow-up time of 3.2 years, SABR was associated with the lowest risk of death within 6 months of diagnosis (hazard ratio [HR] 0.48; 95% confidence interval [CI] 0.38-0.63; referent is lobectomy). After 6 months, lobectomy was associated with the best overall and disease-specific survival. In the propensity-score matched analysis, survival after SABR was similar to that after lobectomy (HR 0.71; 95% CI 0.45-1.12; referent is SABR). Conventional radiation and observation were associated with poor outcomes in all analyses. CONCLUSIONS In this population-based experience, lobectomy was associated with the best long-term outcomes in fit elderly patients with early-stage NSCLC. Exploratory analysis of SABR early adopters suggests efficacy comparable with that of surgery in select populations. Evaluation of these therapies in randomized trials is urgently needed.

Combining radiation and immunotherapy: a new systemic therapy for solid tumors?

With the recent success of checkpoint inhibitors and other immunomodulating agents, there has been renewed interest in the combination of such agents with radiation. The biologic premise behind such a strategy is that the tumor-antigen release achieved by localized radiation will promote specific tumor targeting by the adaptive immune system, which can be augmented further by systemic immune-stimulating agents. In this manner, clinicians hope to induce a phenomenon known as the abscopal effect, whereby localized radiation results in immune-mediated tumor regression in disease sites well outside of the radiation field. Herein, we present a comprehensive overview of the early clinical and preclinical evidence behind this approach. Cancer Immunol Res; 2(9); 831–8. ©2014 AACR.

An Individual Patient Data Metaanalysis of Outcomes and Prognostic Factors After Treatment of Oligometastatic Non-Small-Cell Lung Cancer.

INTRODUCTION/BACKGROUND An individual patient data metaanalysis was performed to determine clinical outcomes, and to propose a risk stratification system, related to the comprehensive treatment of patients with oligometastatic NSCLC. MATERIALS AND METHODS After a systematic review of the literature, data were obtained on 757 NSCLC patients with 1 to 5 synchronous or metachronous metastases treated with surgical metastectomy, stereotactic radiotherapy/radiosurgery, or radical external-beam radiotherapy, and curative treatment of the primary lung cancer, from hospitals worldwide. Factors predictive of overall survival (OS) and progression-free survival were evaluated using Cox regression. Risk groups were defined using recursive partitioning analysis (RPA). Analyses were conducted on training and validating sets (two-thirds and one-third of patients, respectively). RESULTS Median OS was 26 months, 1-year OS 70.2%, and 5-year OS 29.4%. Surgery was the most commonly used treatment for the primary tumor (635 patients [83.9%]) and metastases (339 patients [62.3%]). Factors predictive of OS were: synchronous versus metachronous metastases (P < .001), N-stage (P = .002), and adenocarcinoma histology (P = .036); the model remained predictive in the validation set (c-statistic = 0.682). In RPA, 3 risk groups were identified: low-risk, metachronous metastases (5-year OS, 47.8%); intermediate risk, synchronous metastases and N0 disease (5-year OS, 36.2%); and high risk, synchronous metastases and N1/N2 disease (5-year OS, 13.8%). CONCLUSION Significant OS differences were observed in oligometastatic patients stratified according to type of metastatic presentation, and N status. Long-term survival is common in selected patients with metachronous oligometastases. We propose this risk classification scheme be used in guiding selection of patients for clinical trials of ablative treatment.

Local consolidative therapy versus maintenance therapy or observation for patients with oligometastatic non-small-cell lung cancer without progression after first-line systemic therapy: a multicentre, randomised, controlled, phase 2 study.

Summary Background Retrospective evidence indicates that disease progression after first-line chemotherapy for metastatic non-small cell lung cancer (NSCLC) occurs most often at sites of disease known to exist at baseline. However, the potential benefit of aggressive local consolidative therapy (LCT) on progression-free survival (PFS) for patients with oligometastatic NSCLC is unknown. Methods We conducted a multicenter randomized study (NCT01725165; currently ongoing but not recruiting participants) to assess the effect of LCT on progression-free survival ((PFS). Eligible patients hadwere (1) histologic confirmation of (2) stage IV NSCLC, (3) ≤3 disease sites after systemic therapy, and (4) no disease progression before randomization. Front line therapy was ≥4 cycles of platinum doublet therapy or ≥3 months of inhibitors of epidermal growth factor receptor (EGFR) or anaplastic lymphoma kinase (ALK) for patients with EGFR mutations or ALK rearrangements. Patients were randomized to either LCT ([chemo]radiation or resection of all lesions) +/− maintenance therapy versus maintenance therapy/observation only. Maintenance therapy was recommended based on a list of approved regimens, and observation was defined as close surveillance without cytotoxic therapy. Randomization was not masked and was balanced dynamically on five factors: number of metastases, response to initial therapy, central nervous system metastases, intrathoracic nodal status, and EGFR/ALK status. The primary endpoint was PFS, powered to detect an increase from 4 months to 7 months (hazard ratio [HR}=0.57) using intent-to-treat analysis. The plan was to study 94 randomized patients, with an interim analysis at 44 events. PFS, overall survival (OS), and time to develop a new lesion were compared between arms with log-rank tests. Results The study was terminated early after treatment of 49 patients (25 LCT, 24 control), when at a median follow-up time for PFS of 18.7 months, the median PFS time in the LCT group was 11.9 months (90% confidence interval [CI] 5.72 ,20.90) versus 3.9 months (90% CI 2.30, 6.64) in the maintenance group (HR=0.35, 90% CI 0.18,0.66, log rank p=0.005). Toxicity was similar between groups, with no grade 4–5 events. Grade 3 or higher adverse events in the maintenance therapy arm were fatigue (n=1) and anemia (n=1). In the LCT arm, Grade 3 events were: esophagitis (n=2), anemia (n=1), pneumothorax (n=1), and abdominal pain (n=1). Overall survival data are immature, with only 14 deaths recorded. Interpretation LCT +/− maintenance therapy for patients with ≤3 metastases from NSCLC that did not progress after initial systemic therapy improved PFS relative to maintenance therapy alone. These findings imply that aggressive local therapy should be further explored in phase III trials as a standard treatment option in this clinical scenario.

PDL1 Regulation by p53 via miR-34

Background: Although clinical studies have shown promise for targeting PD1/PDL1 signaling in non–small cell lung cancer (NSCLC), the regulation of PDL1 expression is poorly understood. Here, we show that PDL1 is regulated by p53 via miR-34. Methods: p53 wild-type and p53-deficient cell lines (p53–/– and p53+/+ HCT116, p53-inducible H1299, and p53-knockdown H460) were used to determine if p53 regulates PDL1 via miR-34. PDL1 and miR-34a expression were analyzed in samples from patients with NSCLC and mutated p53 vs wild-type p53 tumors from The Cancer Genome Atlas for Lung Adenocarcinoma (TCGA LUAD). We confirmed that PDL1 is a direct target of miR-34 with western blotting and luciferase assays and used a p53R172HΔg/+K-rasLA1/+ syngeneic mouse model (n = 12) to deliver miR-34a–loaded liposomes (MRX34) plus radiotherapy (XRT) and assessed PDL1 expression and tumor-infiltrating lymphocytes (TILs). A two-sided t test was applied to compare the mean between different treatments. Results: We found that p53 regulates PDL1 via miR-34, which directly binds to the PDL1 3’ untranslated region in models of NSCLC (fold-change luciferase activity to control group, mean for miR-34a = 0.50, SD = 0.2, P < .001; mean for miR-34b = 0.52, SD = 0.2, P = .006; and mean for miR-34c = 0.59, SD = 0.14, and P = .006). Therapeutic delivery of MRX34, currently the subject of a phase I clinical trial, promoted TILs (mean of CD8 expression percentage of control group = 22.5%, SD = 1.9%; mean of CD8 expression percentage of MRX34 = 30.1%, SD = 3.7%, P = .016, n = 4) and reduced CD8+PD1+ cells in vivo (mean of CD8/PD1 expression percentage of control group = 40.2%, SD = 6.2%; mean of CD8/PD1 expression percentage of MRX34 = 20.3%, SD = 5.1%, P = .001, n = 4). Further, MRX34 plus XRT increased CD8+ cell numbers more than either therapy alone (mean of CD8 expression percentage of MRX34 plus XRT to control group = 44.2%, SD = 8.7%, P = .004, n = 4). Finally, miR-34a delivery reduced the numbers of radiation-induced macrophages (mean of F4-80 expression percentage of control group = 52.4%, SD = 1.7%; mean of F4-80 expression percentage of MRX34 = 40.1%, SD = 3.5%, P = .008, n = 4) and T-regulatory cells. Conclusions: We identified a novel mechanism by which tumor immune evasion is regulated by p53/miR-34/PDL1 axis. Our results suggest that delivery of miRNAs with standard therapies, such as XRT, may represent a novel therapeutic approach for lung cancer.

Stereotactic ablative radiation therapy for centrally located early stage or isolated parenchymal recurrences of non-small cell lung cancer: how to fly in a "no fly zone".

PURPOSE We extended our previous experience with stereotactic ablative radiation therapy (SABR; 50 Gy in 4 fractions) for centrally located non-small cell lung cancer (NSCLC); explored the use of 70 Gy in 10 fractions for cases in which dose-volume constraints could not be met with the previous regimen; and suggested modified dose-volume constraints. METHODS AND MATERIALS Four-dimensional computed tomography (4DCT)-based volumetric image-guided SABR was used for 100 patients with biopsy-proven, central T1-T2N0M0 (n=81) or isolated parenchymal recurrence of NSCLC (n=19). All disease was staged with positron emission tomography/CT; all tumors were within 2 cm of the bronchial tree, trachea, major vessels, esophagus, heart, pericardium, brachial plexus, or vertebral body. Endpoints were toxicity, overall survival (OS), local and regional control, and distant metastasis. RESULTS At a median follow-up time of 30.6 months, median OS time was 55.6 months, and the 3-year OS rate was 70.5%. Three-year cumulative actuarial local, regional, and distant control rates were 96.5%, 87.9%, and 77.2%, respectively. The most common toxicities were chest-wall pain (18% grade 1, 13% grade 2) and radiation pneumonitis (11% grade 2 and 1% grade 3). No patient experienced grade 4 or 5 toxicity. Among the 82 patients receiving 50 Gy in 4 fractions, multivariate analyses showed mean total lung dose >6 Gy, V20 >12%, or ipsilateral lung V30 >15% to independently predict radiation pneumonitis; and 3 of 9 patients with brachial plexus Dmax >35 Gy experienced brachial neuropathy versus none of 73 patients with brachial Dmax <35 Gy (P=.001). Other toxicities were analyzed and new dose-volume constraints are proposed. CONCLUSIONS SABR for centrally located lesions produces clinical outcomes similar to those for peripheral lesions when normal tissue constraints are respected.

Long-Term Clinical Outcome of Intensity-Modulated Radiotherapy for Inoperable Non-Small Cell Lung Cancer: The MD Anderson Experience

PURPOSE In 2007, we published our initial experience in treating inoperable non-small-cell lung cancer (NSCLC) with intensity-modulated radiation therapy (IMRT). The current report is an update of that experience with long-term follow-up. METHODS AND MATERIALS Patients in this retrospective review were 165 patients who began definitive radiotherapy, with or without chemotherapy, for newly diagnosed, pathologically confirmed NSCLC to a dose of ≥60 Gy from 2005 to 2006. Early and late toxicities assessed included treatment-related pneumonitis (TRP), pulmonary fibrosis, esophagitis, and esophageal stricture, scored mainly according to the Common Terminology Criteria for Adverse Events 3.0. Other variables monitored were radiation-associated dermatitis and changes in body weight and Karnofsky performance status. The Kaplan-Meier method was used to compute survival and freedom from radiation-related acute and late toxicities as a function of time. RESULTS Most patients (89%) had Stage III to IV disease. The median radiation dose was 66 Gy given in 33 fractions (range, 60-76 Gy, 1.8-2.3 Gy per fraction). Median overall survival time was 1.8 years; the 2-year and 3-year overall survival rates were 46% and 30%. Rates of Grade ≥3 maximum TRP (TRP(max)) were 11% at 6 months and 14% at 12 months. At 18 months, 86% of patients had developed Grade ≥1 maximum pulmonary fibrosis (pulmonary fibrosis(max)) and 7% Grade ≥2 pulmonary fibrosis(max). The median times to maximum esophagitis (esophagitis(max)) were 3 weeks (range, 1-13 weeks) for Grade 2 and 6 weeks (range, 3-13 weeks) for Grade 3. A higher percentage of patients who experienced Grade 3 esophagitis(max) later developed Grade 2 to 3 esophageal stricture. CONCLUSIONS In our experience, using IMRT to treat NSCLC leads to low rates of pulmonary and esophageal toxicity, and favorable clinical outcomes in terms of survival.

Improved survival outcomes with the incidental use of beta-blockers among patients with non-small-cell lung cancer treated with definitive radiation therapy

BACKGROUND Preclinical studies have shown that norepinephrine can directly stimulate tumor cell migration and that this effect is mediated by the beta-adrenergic receptor. PATIENTS AND METHODS We retrospectively reviewed 722 patients with non-small-cell lung cancer (NSCLC) who received definitive radiotherapy (RT). A Cox proportional hazard model was utilized to determine the association between beta-blocker intake and locoregional progression-free survival (LRPFS), distant metastasis-free survival (DMFS), disease-free survival (DFS), and overall survival (OS). RESULTS In univariate analysis, patients taking beta-blockers (n = 155) had improved DMFS (P < 0.01), DFS (P < 0.01), and OS (P = 0.01), but not LRPFS (P = 0.33) compared with patients not taking beta-blockers (n = 567). In multivariate analysis, beta-blocker intake was associated with a significantly better DMFS [hazard ratio (HR), 0.67; P = 0.01], DFS (HR, 0.74; P = 0.02), and OS (HR, 0.78; P = 0.02) with adjustment for age, Karnofsky performance score, stage, histology type, concurrent chemotherapy, radiation dose, gross tumor volume, hypertension, chronic obstructive pulmonary disease and the use of aspirin. There was no association of beta-blocker use with LRPFS (HR = 0.91, P = 0.63). CONCLUSION Beta-blocker use is associated with improved DMFS, DFS, and OS in this large cohort of NSCLC patients. Future prospective trials can validate these retrospective findings and determine whether the length and timing of beta-blocker use influence survival outcomes.

Scientific advances in lung cancer 2015

ABSTRACT Lung cancer continues to be a major global health problem; the disease is diagnosed in more than 1.6 million new patients each year. However, significant progress is underway in both the prevention and treatment of lung cancer. Lung cancer therapy has now emerged as a “role model” for precision cancer medicine, with several important therapeutic breakthroughs occurring during 2015. These advances have occurred primarily in the immunotherapy field and in treatments directed against tumors harboring specific oncogenic drivers. Our knowledge about molecular mechanisms for oncogene‐driven tumors and about resistance to targeted therapies has increased quickly over the past year. As a result, several regulatory approvals of new agents that significantly improve survival and quality of life for patients with lung cancer who have advanced disease have occurred. The International Association for the Study of Lung Cancer has gathered experts in different areas of lung cancer research and management to summarize the most significant scientific advancements related to prevention and therapy of lung cancer during the past year.

Intensity-Modulated Proton Therapy Further Reduces Normal Tissue Exposure During Definitive Therapy for Locally Advanced Distal Esophageal Tumors: A Dosimetric Study

PURPOSE We have previously found that ≤ 75% of treatment failures after chemoradiotherapy for unresectable esophageal cancer appear within the gross tumor volume and that intensity-modulated (photon) radiotherapy (IMRT) might allow dose escalation to the tumor without increasing normal tissue toxicity. Proton therapy might allow additional dose escalation, with even lower normal tissue toxicity. In the present study, we compared the dosimetric parameters for photon IMRT with that for intensity-modulated proton therapy (IMPT) for unresectable, locally advanced, distal esophageal cancer. PATIENTS AND METHODS Four plans were created for each of 10 patients. IMPT was delivered using anteroposterior (AP)/posteroanterior beams, left posterior oblique/right posterior oblique (LPO/RPO) beams, or AP/LPO/RPO beams. IMRT was delivered with a concomitant boost to the gross tumor volume. The dose was 65.8 Gy to the gross tumor volume and 50.4 Gy to the planning target volume in 28 fractions. RESULTS Relative to IMRT, the IMPT (AP/posteroanterior) plan led to considerable reductions in the mean lung dose (3.18 vs. 8.27 Gy, p<.0001) and the percentage of lung volume receiving 5, 10, and 20 Gy (p≤.0006) but did not reduce the cardiac dose. The IMPT LPO/RPO plan also reduced the mean lung dose (4.9 Gy vs. 8.2 Gy, p<.001), the heart dose (mean cardiac dose and percentage of the cardiac volume receiving 10, 20, and 30 Gy, p≤.02), and the liver dose (mean hepatic dose 5 Gy vs. 14.9 Gy, p<.0001). The IMPT AP/LPO/RPO plan led to considerable reductions in the dose to the lung (p≤.005), heart (p≤.003), and liver (p≤.04). CONCLUSIONS Compared with IMRT, IMPT for distal esophageal cancer lowered the dose to the heart, lung, and liver. The AP/LPO/RPO beam arrangement was optimal for sparing all three organs. The dosimetric benefits of protons will need to be tailored to each patient according to their specific cardiac and pulmonary risks. IMPT for esophageal cancer will soon be investigated further in a prospective trial at our institution.