Patterns of Disease Recurrence after SABR for Early Stage Non–Small-Cell Lung Cancer: Optimizing Follow-Up Schedules for Salvage Therapy

RBM10 Mutation as a Potential Negative Prognostic/Predictive Biomarker to Therapy in Non-Small-Cell Lung Cancer

BACKGROUND

According to WHO, lung cancer is the leading cause of cancer-related death worldwide, but treatment has advanced in the last decade. The widespread use of Next Generation Sequencing has led to the discovery of several pathogenic mutations including RNA binding motif 10 (RBM10), a part of the spliceosome complex that regulates splicing of pre-mRNA.

PATIENTS AND METHODS

Electronic medical records were utilized to create a database of patients (50 patients) seen from 2018-2023 with NSCLC and RBM10 mutations, with appropriate IRB approval. For subgroup analysis, we separated into groups by rapid progression vs stable disease defined as progression-free survival earlier than respective clinical trials.

RESULTS

From the analysis of treatment response the mutated RBM10 population had a median PFS was 6.7 months compared to 13.9 in the wild-type RBM10 population controlled for driver mutations TP53 mutation had a higher representation in the RBM10 mutated rapid progression group than the stable disease group. The ZFHX3 mutation had a higher representation in the RBM10 mutated stable disease group.

CONCLUSIONS

RBM10 mutations were associated with aggressive disease with treatment progression faster than median durations of response. RBM10 mutations with concurrent ZFHX3 and EGFR mutations were associated with more stable disease, while concurrent KRAS and TP53 predicted even more aggressive disease.

Reirradiation with stereotactic body radiotherapy for primary or secondary lung malignancies: Tumor control probability and safety analyses

BACKGROUND

Reirradiation with stereotactic body radiotherapy (SBRT) for patients with primary or secondary lung malignancies represents an appealing definitive approach, but its feasibility and safety are not well defined. The purpose of this study was to investigate the tumor control probability (TCP) and toxicity for patients receiving reirradiation with SBRT.

PATIENTS AND METHODS

Eligible patients with recurrence of primary or secondary lung malignancies from our hospital were subjected to reirradiation with SBRT, and PubMed- and Embase-indexed articles were reviewed. The patient characteristics, pertinent SBRT dosimetric details, local tumor control, and toxicities were extracted. The logistic dose-response models were compared for TCP and overall survival (OS) in terms of the physical dose and three-, four-, and five-fraction equivalent doses.

RESULTS

The data of 17 patients from our hospital and 195 patients extracted from 12 articles were summarized. Reirradiation with SBRT yielded 2-year estimates of 80% TCP for doses of 50.10 Gy, 55.85 Gy, and 60.54 Gy in three, four, and five fractions, respectively. The estimated TCP with common fractionation schemes were 50%, 60%, and 70% for 42.04 Gy, 47.44 Gy, and 53.32 Gy in five fractions, respectively. Similarly, the 2-year estimated OS was 50%, 60%, and 70% for 41.62 Gy, 46.88 Gy, and 52.55 Gy in five fractions, respectively. Central tumor localization may be associated with severe toxicity.

CONCLUSIONS

Reirradiation with SBRT doses of 50-60 Gy in 3-5 fractions is feasible for appropriately selected patients with recurrence of peripheral primary or secondary lung malignancies, but should be carefully considered for centrally-located tumors due to potentially severe toxicity. Further studies are warranted for optimal dose/fractionation schedules and more accurate selection of patients suitable for reirradiation with SBRT.

Survival and quality-of-life outcomes in early-stage NSCLC patients: a literature review of real-world evidence

Aim

Assess the long-term survival and quality-of-life outcomes in early-stage NSCLC (eNSCLC) patients.

Methods

Review of long-term survival and quality-of-life after curative treatment in eNSCLC patients in observational studies.

Results

Disease-free proportion decreased in stage III vs stage I patients. Recurrence-free proportion decreased with age and disease stage. Advanced stage and vascular invasion increased risk of late recurrence. Conditional 5-year relative survival rates did not exceed 87%, indicating higher mortality in eNSCLC survivors. Lower conditional survival rates and relative survival rates were associated with older age and advanced disease. Survivors of eNSCLC had poorer physical quality-of-life.

Conclusion

Despite curative-intent therapy, survivors of eNSCLC still face significant risks of recurrence, excess mortality, and diminished quality-of-life.

Retrospective comparison between definitive stereotactic body radiotherapy and radical surgery for 538 patients with early-stage non-small cell lung cancer in a single institution

Introduction

Survival information for stereotactic body radiotherapy (SBRT) and surgery for stage I non-small cell lung cancer (NSCLC) was examined.

Methods

Stage I NSCLC patients who underwent surgery or SBRT between 2012 and 2016 were retrospectively enrolled in this single-institution study. Using the Kaplan--Meier method and Cox regression model, overall survival (OS) was estimated and compared.

Results

Among 538 enrolled patients, compared to the surgery group (443), the SBRT group (95) had more complications (P = 0.01), worse performance status (P = 0.001), and were older (P < 0.001). Three-year OS was 70.5% post SBRT and 90.1% postsurgery. The 3-year cancer-specific survival (CSS) and disease-free survival (DFS) post SBRT and postsurgery were 92.7% vs. 92.3% and 61.1% vs 79.3%, respectively. Three-year locoregional and distant control rates post SBRT and postsurgery were 85.6% vs. 90.1% and 82.5% vs. 86.4%, respectively. Multivariate analysis using the Cox model, including age, T-stage, CCI, and C/T ratio and treatment, showed the surgery group's OS to be significantly superior to that of the SBRT group (HR of SBRT per surgery: 1.90, 95%CI: 1.12-3.21, P = 0.017). No significant differences were observed in rates of adverse events.

Conclusion

Although OS was better in the surgery group, no differences in CSS existed. This analysis suggests the need for future studies that compare specific radical surgeries and SBRT in a prospective and randomized setting.

Comparison of outcome after stereotactic ablative radiotherapy of patients with metachronous lung versus primary lung cancer

BACKGROUND

Early-stage lung cancer, primarily treated with surgery, often occur in poor surgical candidates (impaired respiratory function, prior thoracic surgery, severe comorbidities). Stereotactic ablative radiotherapy (SABR) is a non-invasive alternative that provides comparable local control. This technique is particularly relevant for surgically resectable metachronous lung cancer, in patients unable to undergo surgery.. The objective of this study is to evaluate the clinical outcome of patients treated with SABR for stage I metachronous lung cancer (MLC) versus stage I primary lung cancer (PLC).

PATIENTS AND METHODS

137 patients treated with SABR for stage I non-small cell lung cancer were retrospectively reviewed, of which 28 (20.4%) were MLC and 109 (79.6%) were PLC. Cohorts were evaluated for differences in overall survival (OS), progression-free survival (PFS), metastasis-free survival, local control (LC), and toxicity.

RESULTS

After SABR, patients treated for MLC have comparable median age (76.6 vs 78.6, p = 0.2), 3-year LC (83.6% vs. 72.6%, p = 0.2), PFS (68.7% vs. 50.9%, p = 0.9), and OS (78.6% vs. 52.1%, p = 0.9) as PLC, along with similar rates of total (54.1% vs. 42.9%, p = 0.6) and grade 3 + toxicity (3.7% vs. 3.6%, p = 0.9). Previous treatment of MLC patients was either surgery (21/28, 75%) or SABR (7/28, 25%). The median follow-up was 53 months.

CONCLUSION

SABR is a safe and effective approach for localized metachronous lung cancer.

Stereotactic Ablative Radiotherapy in the Treatment of Early-Stage Lung Cancer - A Done Deal?

Stereotactic ablative radiotherapy (SABR) is an important curative-intent treatment option for early-stage non-small cell lung cancer. It offers good cancer control without invasive surgery and has become the standard of care for medically inoperable patients. The literature on SABR for early-stage non-small cell lung cancer is substantial and continues to grow. However, there remain areas of controversy where data are limited - notably the use of SABR in medically operable patients. Other areas of some debate include the treatment of central/ultra-central and large (>5 cm) lesions, as well as treatment with co-existing interstitial lung disease. This review article provides an overview of the current literature together with a discussion of future directions.

Systematic Review of Single-Fraction Stereotactic Body Radiation Therapy for Early Stage Non-Small-Cell Lung Cancer and Lung Oligometastases: How to Stop Worrying and Love One and Done

Adoption of single-fraction lung stereotactic body radiation therapy (SBRT) for patients with medically inoperable early stage non-small-cell lung cancer (NSCLC) or oligometastatic lung disease, even during the coronavirus disease 2019 (COVID-19) pandemic, was limited despite encouraging phase II trial results. Barriers to using single-fraction SBRT may include lack of familiarity with the regimen and lack of clarity about the expected toxicity. To address these concerns, we performed a systematic review of prospective literature on single-fraction SBRT for definitive treatment of early stage and oligometastatic lung cancer. A PubMed search of prospective studies in English on single-fraction lung SBRT was conducted. A systematic review was performed of the studies that reported clinical outcomes of single-fraction SBRT in the treatment of early stage non-small-cell lung cancer and lung oligometastases. The current prospective literature including nine trials supports the use of single-fraction SBRT in the definitive treatment of early stage peripheral NSCLC and lung oligometastases. Most studies cite local control rates of >90%, mild toxicity profiles, and favorable survival outcomes. Most toxicities reported were grade 1–2, with grade ≥3 toxicity in 0–17% of patients. Prospective trial results suggest potential consideration of utilizing single-fraction SBRT beyond the COVID-19 pandemic.

Impact of local recurrence on cause-specific death after stereotactic body radiotherapy for early-stage non-small cell lung cancer: dynamic prediction using landmark model

PURPOSE

The purpose of this study was to assess the impact of local recurrence (LR) on cause-specific death (CSD) in patients with non-small cell lung cancer (NSCLC) treated with stereotactic body radiotherapy (SBRT). A dynamic prediction model that incorporated LR as a time-dependent covariate was used.

METHODS AND MATERIALS

This study included 535 stage I (cT1-T2aN0M0) NSCLC patients treated with SBRT from two institutions. We developed a landmark dynamic prediction model to estimate the probability of a CSD. This model determined the probability of surviving for an additional 3 years at different prediction time points during follow-up, given the history of recurrence status. The baseline covariates included in the model were age, sex, T stage, and histology, while the time-dependent covariates were LR and regional and/or distant recurrence (RDR) status.

RESULTS

Overall, 137 patients (25.6%) died of lung cancer within a median follow-up of 4.1 years. Of the 195 patients who developed recurrence, 28, 125, and 42 patients had LR only, RDR only, and both, respectively. The landmark model showed that older age, advanced T stage, LR, and RDR were significantly associated with an increased risk of subsequent CSD. Among these covariates, LR (odds ratio [OR], 8.5; 95% confidence interval [CI], 6.0-12.0; P < .001) and RDR (OR, 11.6; 95% CI, 9.1-14.9; P < .001) demonstrated strong effects on CSD within 3 years after the prediction time points. The dynamic prediction provided information on the probability of future CSD according to individual recurrence status during follow-up.

CONCLUSIONS

Dynamic prediction using the landmark model showed that LR had a substantial impact on subsequent CSD, which was comparable to that of RDR. This result supports the notion that strategies to improve local control are reasonable.

Multi-disciplinary approach for the management of non-metastatic non-small cell lung cancer in the Middle East and Africa: Expert panel recommendations

The Middle East and Africa (MEA) region, a large geographical area, lies at the confluence of Asian, Caucasian and African races and comprises of a population with several distinct ethnicities. The course of management of non-small cell lung cancer (NSCLC) differs as per patients' performance status as well as stage of disease, requiring personalized therapy decisions. Although management of NSCLC has received a significant impetus in the form of molecularly targeted therapies and immune therapies in last few years, surgery remains gold standard for patients with early-stage disease. In case of unresectable disease, radiotherapy and chemotherapy are the primary management modalities. With newer therapies being approved for treatment of early stage disease, use of multi-disciplinary team (MDT) for comprehensive management of NSCLC is of prime importance. A group of experts with interest in thoracic oncology, deliberated and arrived at a consensus statement for the community oncologists treating patients with NSCLC in the MEA region. The deliberation was based on the review of the published evidence including literature and global and local guidelines, subject expertise of the participating panellists and experience in real-life management of patients with NSCLC. We present the proposed regional adaptations of international guidelines and recommends the MDT approach for management of NSCLC in MEA.

Stage I non-small cell lung cancer: Treatment modalities, Dutch daily practice and future perspectives

OBJECTIVES

Several treatment modalities are available for patients with stage I non-small cell lung cancer (NSCLC). Over the past decade, these treatment modalities have been further investigated and might have changed current treatment regimens. In this review we present an overview of the treatment options, developments and future perspectives for stage I NSCLC. Furthermore, we describe the current use of these treatment modalities in the Netherlands.

MATERIALS AND METHODS

A bibliographical search was performed in PubMed and the Cochrane Library for publications concerning treatment modalities for stage I NSCLC. In addition, evidence-based guidelines of the European Society for Medical Oncology (ESMO) and the National Comprehensive Cancer Network (NCCN) were studied.

RESULTS

The guideline-recommended treatment for operable stage I NSCLC patients is a lobectomy with systematic lymph node dissection. Inoperable patients or those refusing surgery are offered stereotactic ablative radiotherapy (SABR). Percutaneous ablation, such as radiofrequency ablation, is a non-surgical minimally invasive technique offered to those who are ineligible for surgery or SABR. The role of systemic therapy is currently limited. However, the efficacy of immunotherapy is being investigated in clinical trials. In the Netherlands, an increasing use of SABR and a relative decrease in resection rates have been observed.

CONCLUSION

Surgery and SABR are currently the prevailing treatment modalities for stage I NSCLC patients. Despite optimization of treatment regimens, survival of patients with stage I NSCLC remains to be improved. Future studies are required to optimize treatment strategies, but also to investigate factors influencing treatment decision-making for patients with stage I NSCLC.

Effectiveness of Thermal Ablation and Stereotactic Radiotherapy Based on Stage I Lung Cancer Histology

PURPOSE

To assess whether the effectiveness of thermal ablation (TA) and stereotactic body radiotherapy (SBRT) as initial treatments for stage I lung cancer varies depending on the histological subtype.

MATERIALS AND METHODS

The 2004-2016 National Cancer Database was queried for patients with American Joint Committee on Cancer stage I lung cancer treated with TA or SBRT. Patients <18 years, those treated with surgery or chemotherapy, or those with unknown survival and follow-up were excluded. TA and SBRT patients were 1:5 propensity score matched separately for each histological subtype to adjust for confounders. Overall survival (OS) was assessed using Cox models.

RESULTS

A total of 28,425 patients were included (SBRT, n = 27,478; TA, n = 947). TA was more likely to be used in Caucasian patients, those with more comorbidities and smaller neuroendocrine tumors (NETs) of the lower lobe, and those whose treatment had taken place in the northeastern United States. After propensity score matching, a cohort with 4,085 SBRT and 817 TA patients with balanced confounders was obtained. In this cohort, OS for TA and SBRT was comparable (hazard ratio = 1.07; 95% confidence interval,0.98-1.18; P = .13), although it varied by histological subtypes: higher OS for TA was observed in patients with non-small cell NETs (vs SBRT hazard ratio = 0.48; 95% confidence interval, 0.24-0.95; P = .04). No significant OS differences between TA and SBRT were noted for adenocarcinomas, squamous cell carcinomas, small cell carcinomas, and non-neuroendocrine large cell carcinomas (each, P > .1).

CONCLUSIONS

OS following TA and SBRT for stage I lung cancer is comparable for most histological subtypes, except that OS is longer after TA in non-small cell NETs.

Stereotactic ablative radiotherapy as single treatment for early stage non-small cell lung cancer: A single institution analysis

BACKGROUND

Stereotactic ablative radiotherapy (SABR) is the current standard-of-care in cases of inoperable early stage non-small cell lung cancer (ES-NSCLC). This study aimed to assess the survival outcomes and recurrence patterns after SABR for ES-NSCLC in a hospital setting.

METHODS

A single-institution retrospective study was performed which included 109 patients who had undergone SABR. The main study endpoints were overall survival (OS), cancer specific survival (CSS), local recurrence-free survival (LRFS), regional recurrence free survival (RRFS) and distant metastasis-free survival (DMFS). Univariate and multivariate analysis were conducted to explore the potential factors which might be related to patient survival.

RESULTS

A total of 109 patients were enrolled into the study. Median follow-up was 44 months (range: 2-93 months). (i) Recurrence results: Among 45 patients with recurrence, 30 patients (28%) had distant metastasis (DM), 17 patients (16%) had local recurrence (LR), 10 patients (9%) had regional recurrence (RR) of lymph nodes and two patients (2%) had second primary lung cancer (SPLC). (ii) Survival results: Median OS, CSS, PFS was 78 months, 78 and 40 months. Two-year OS, CSS, PFS, LRFS, RRFS and DMFS was 84.7%, 87.1%, 69.2%, 86.8%, 92.7% and 78.0%, respectively. Four-year OS, CSS, PFS, LRFS, RRFS and DMFS was 55.6%, 60.7%, 37.3%, 76.3%, 88.4% and 59.4%, respectively. (iii) Univariate and multivariate analyses indicated that age was a prognostic factor of CSS in patients aged <75 years (P = 0.04 HR 2.12 95% confidence interval [CI]: 1.04-4.33).

CONCLUSIONS

Although high survival rates can be achieved in ES-NSCLC patients treated with SABR, using SABR on its own may not be enough. Prolonged surveillance and adjuvant therapy is therefore needed.

Pretransplant solid organ malignancy and organ transplant candidacy: A consensus expert opinion statement

Patients undergoing evaluation for solid organ transplantation (SOT) often have a history of malignancy. Although the cancer has been treated in these patients, the benefits of transplantation need to be balanced against the risk of tumor recurrence, especially in the setting of immunosuppression. Prior guidelines of when to transplant patients with a prior treated malignancy do not take in to account current staging, disease biology, or advances in cancer treatments. To develop contemporary recommendations, the American Society of Transplantation held a consensus workshop to perform a comprehensive review of current literature regarding cancer therapies, cancer stage-specific prognosis, the kinetics of cancer recurrence, and the limited data on the effects of immunosuppression on cancer-specific outcomes. This document contains prognosis based on contemporary treatment and transplant recommendations for breast, colorectal, anal, urological, gynecological, and nonsmall cell lung cancers. This conference and consensus documents aim to provide recommendations to assist in the evaluation of patients for SOT given a history of a pretransplant malignancy.

Survival Outcomes of Salvage Therapy for Local and Regionally Recurrent NSCLC

Introduction

The treatment of locally recurrent NSCLC after initial curative therapy is variable. We sought to perform a real-world analysis of curative and palliative therapeutic strategies used in locally recurrent NSCLC and explore the impact of baseline factors and the previous and recurrent treatment on outcomes.

Methods

A retrospective cohort study was done including all patients with stage I to III NSCLC who were referred to BC Cancer and received curative-intent therapy between 2005 and 2012. Patients were followed up to determine whether they developed locoregional recurrence. Two cohorts were created: curative-intent treatment at recurrence (surgery, radiotherapy with ≥50Gy ± chemotherapy, stereotactic radiosurgery) and palliative treatment. The primary outcome was overall survival (OS).

Results

A total of 1571 patients received curative-intent therapy during the study period. Of these, 179 (11%) developed a local and regional recurrence. A total of 51 patients (28%) were treated with curative intent at recurrence (12 surgery, 39 radiotherapy ± chemotherapy), and 128 (72%) received palliative treatment only. Patients receiving curative-intent therapy were more likely to have an Eastern Cooperative Oncology Group performance status of 0 to 1 (90% versus 58%), earlier stage at diagnosis (51% stage I) and receive more aggressive staging investigations at recurrence, pathologic confirmation (75% versus 27%) and positron emission tomography (77% versus 27%). OS was longer in the cohort receiving curative-intent therapy, with an OS of 34.3 months versus 9.8 months (p < 0.001) in palliative treatment.

Conclusions

In this real-world population, isolated locoregional recurrences occurred in 11% of patients. Curative-intent treatment at recurrence is associated with a reasonable chance of long-term survival, making aggressive therapy of locoregional recurrences an important treatment consideration.

ESMO Management and treatment adapted recommendations in the COVID-19 era: Lung cancer

The COVID-19 pandemic, characterised by a fast and global spread during the first months of 2020, has prompted the development of a structured set of recommendations for cancer care management, to maintain the highest possible standards. Within this framework, it is crucial to ensure no disruption to essential oncological services and guarantee the optimal care.This is a structured proposal for the management of lung cancer, comprising three levels of priorities, namely: tier 1 (high priority), tier 2 (medium priority) and tier 3 (low priority)-defined according to the criteria of the Cancer Care Ontario, Huntsman Cancer Institute and Magnitude of Clinical Benefit Scale.The manuscript emphasises the impact of the COVID-19 pandemic on lung cancer care and reconsiders all steps from diagnosis, staging and treatment.These recommendations should, therefore, serve as guidance for prioritising the different aspects of cancer care to mitigate the possible negative impact of the COVID-19 pandemic on the management of our patients.As the situation is rapidly evolving, practical actions are required to guarantee the best patients' treatment while protecting and respecting their rights, safety and well-being. In this environment, cancer practitioners have great responsibilities: provide timely, appropriate, compassionate and justified cancer care, while protecting themselves and their patients from being infected with COVID-19. In case of shortages, resources must be distributed fairly. Consequently, the following recommendations can be applied with significant nuances, depending on the time and location for their use, considering variable constraints imposed to the health systems. An exceptional flexibility is required from cancer caregivers.

Circulating Tumor Cells Are Associated with Recurrent Disease in Patients with Early-Stage Non-Small Cell Lung Cancer Treated with Stereotactic Body Radiotherapy

PURPOSE

Although stereotactic body radiotherapy (SBRT) is effective in early-stage non-small cell lung cancer (NSCLC), approximately 10%-15% of patients will fail regionally and 20%-25% distantly. We evaluate a novel circulating tumor cell (CTC) assay as a prognostic marker for increased risk of recurrence following SBRT.

EXPERIMENTAL DESIGN

Ninety-two subjects (median age, 71 years) with T1a (64%), T1b (23%), or T2a (13%) stage I NSCLC treated with SBRT were prospectively enrolled. CTCs were enumerated by utilizing a GFP-expressing adenoviral probe that detects elevated telomerase activity in cancer cells. Samples were obtained before, during, and serially up to 24 months after treatment. SBRT was delivered to a median dose of 50 Gy (range, 40-60 Gy), mostly commonly in four to five fractions (92%).

RESULTS

Thirty-eight of 92 subjects (41%) had a positive CTC test prior to SBRT. A cutoff of ≥5 CTCs/mL before treatment defined favorable (n = 78) and unfavorable (n = 14) prognostic groups. Increased risk of nodal (P = 0.04) and distant (P = 0.03) failure was observed in the unfavorable group. Within 3 months following SBRT, CTCs continued to be detected in 10 of 35 (29%) subjects. Persistent detection of CTCs was associated with increased risk of distant failure (P = 0.04) and trended toward increased regional (P = 0.08) and local failure (P = 0.16).

CONCLUSIONS

Higher pretreatment CTCs and persistence of CTCs posttreatment is significantly associated with increased risk of recurrence outside the targeted treatment site. This suggests that CTC analysis may potentially identify patients at higher risk for regional or distant recurrences and who may benefit from either systemic therapy and/or timely locoregional salvage treatment.

Effects of the recurrence pattern on patient survival following SABR for stage I lung cancer

Background: Information on the effect of the recurrence pattern on survival for stage I lung cancer following stereotactic ablative radiotherapy (SABR) is limited.Materials and Methods: The recurrence pattern was analyzed for 100 consecutive stage I non-small-cell lung cancer patients treated with SABR using predominantly 12 Gy × 4. Recurrences were classified as local, regional lymph nodes and distant. Distant recurrences included recurrences in the lung and outside the chest. Single lung recurrences were named solitary, if no other location was involved. Kaplan-Meier survival estimates were calculated for different locations of recurrence. Clinical and dosimetrical factors affecting survival were also analyzed.Results: Median follow-up was 32 months (3-123), median age 70 years (49-95). In total, 31 patients had recurrences after a median 21 months (4-60): 5 local; 10 regional; 8 distant outside the chest; 25 non-local lung recurrences, of which 15 were single - 10 of which solitary - and 10 multiple lung nodules. Patients with a solitary lung recurrence had longer survival compared to local or distant recurrences (p = .04 each), and compared to multiple lung nodules (p = .09). 3-year local recurrence-free survival was 92%, disease-free survival 69% and overall survival 59%. On multivariate analysis, disease-free survival was associated with statin use (p = .038) and tumor location (p = .035). Smoking history predicted overall survival (p < .0006).Conclusions: A total of 81% of recurrences involved the lungs. Patients with solitary lung recurrences/second primary lung cancers had the longest overall survival suggesting definitive treatment should be considered. The effects of statin use need to be explored further.

Salvage Therapy for Locoregional Recurrence After Stereotactic Ablative Radiotherapy for Early-Stage NSCLC

Although isolated local (LRs) and regional recurrences (RRs) constitute a minority of post-stereotactic ablative radiotherapy (SABR) relapses, their management is becoming increasingly important as the use of SABR continues to expand. However, few evidence-based strategies are available to guide treatment of these potentially curable recurrences. On behalf of the Advanced Radiation Technology Committee of the International Association for the Study of Lung Cancer, this article was written to address management of recurrent disease. Topics discussed include diagnosis and workup, including the roles of volumetric and functional imaging as well as histopathologic methods; clinical outcomes after salvage therapy; patterns of recurrence after salvage therapy; and management options. Our main conclusions are that survival for patients with adequately salvaged LRs is similar to that for patients after primary SABR without recurrence, and survival for those with salvaged RRs (regardless of nodal burden or location) is similar to that of patients with de novo stage III disease. Although more than half of patients who undergo salvage do not develop a second relapse, the predominant pattern of second failure is distant, especially for RRs. Management requires rigorous multidisciplinary coordination. Isolated LRs can be managed with resection and nodal dissection, repeat SABR, thermal ablation, or systemic therapies. RRs can be treated with combined chemoradiotherapy, radiation or chemotherapy alone, or supportive services. Finally, regular and structured follow-up is recommended after post-SABR salvage therapy.

Idiopathic pulmonary fibrosis in patients with early-stage non-small-cell lung cancer after surgical resection

Background The outcomes of patients with both lung cancer and idiopathic pulmonary fibrosis (IPF) are unfavorable. Therapeutic interventions for lung cancer such as surgery can cause acute exacerbation of IPF (aeIPF). This study aimed to assess the frequency of IPF in a group of patients with early-stage non-small-cell lung cancer (NSCLC) and to report clinical characteristics and outcomes of this cohort of patients. Patients and methods This observational cohort retrospective study analyzed 641 pathological records of patients after surgical resection of early-stage non-small-cell lung cancer (NSCLC) at University Clinic Golnik from May 2010 to April 2017. Pathological records of NSCLC with coexisting IPF were reviewed. CT scans and biopsy specimens for this group of patients were analyzed by a thoracic radiologist and pathologist, independently. We searched radiological and pathological features of usual interstitial pneumonia (UIP) pattern in this group of patients. We report the clinical characteristics and outcome of this cohort of patients. Results Out of 641 patients with early-stage NSCLC, only 13 (2.0%) had histologically and radiologically proven coexisting UIP/IPF. Squamous cell carcinoma was the most common type of lung cancer (7/13 patients). The majority of tumors were small size (all being pT1 or pT2), stage I-II (11/13 patients), located in the lower lung lobes (11/13 patients). Almost all patients were current or ex-smokers (11/13 patients). There were two pathologically confirmed fatal cases (15.4%) due to aeIPF in the first two months after radical treatment, one after adjuvant radiotherapy and the other after surgery. Out of 13 patients, one patient had a lung cancer relapse. Conclusions Frequency of UIP/IPF in surgically treated early stage NSCLC is rather low. Our observational study shows that radical treatment of lung cancer can cause aeIPF with dismal outcome in this group of patients. The standard of care in these mostly elderly patients still remains unresolved.

Pathologic response after modern radiotherapy for non-small cell lung cancer

In non-small cell lung cancer (NSCLC), pathologic complete response (pCR) following radiotherapy treatment has been shown to be an independent prognostic factor for long-term survival, progression-free survival and locoregional control. PCR is considered a surrogate to therapeutic efficacy, years before survival data are available, and therefore can be used to guide treatment plans and additional therapeutic interventions post-surgical resection. Given the extensive fibrotic changes induced by radiotherapy in the lung, radiological assessment of response can potentially misrepresent pathologic response. The optimal timing for assessment of pathologic response after conventionally fractionated radiotherapy and stereotactic ablative radiotherapy (SABR) remains poorly understood. In this review, we summarize recent literature on pathologic response after radiotherapy for early stage and locally advanced NSCLC, we discuss current controversies around radiobiological considerations, and we present upcoming trials that will provide insight into current knowledge gaps.

Management of local recurrences and regional failure in early stage non-small cell lung cancer after stereotactic body radiation therapy

Stereotactic body radiation therapy (SBRT) is a very effective way to treat early stage non-small cell lung cancer (NSCLC) and small oligometastatic lung lesions with consistently high rates of local control, but both local and regional/distant recurrences still occur. The management of recurrences remains unsettled and may entail repeat SBRT, conventionally fractionated external beam RT (EF-EBRT), chemotherapy or surgery. Most patients with local recurrences [within the initial planning target volume (PTV)] can be salvaged successfully with good cancer specific survival. Nonetheless, proximity of the initial SBRT delivery to organs at risk (ribs, blood vessels, airways) may make retreatment more difficult. With attention to detail and careful patient selection, both surgery and reirradiation can be performed safely and effectively. Strategies for management of regional (nodal) recurrences may require conventional therapies tailored to the patterns of failure. The role of immunotherapy in salvage has not been elucidated as yet. We review here data on the available literature concerning salvage of SBRT lung patients.

The advanced radiotherapy network (ART-NET) UK lung stereotactic ablative radiotherapy survey: national provision and a focus on image guidance

OBJECTIVE

Stereotactic ablative radiotherapy (SABR) has become the standard of care for suitable patients with peripherally located early stage non-small cell lung cancer. Lung SABR requires strict image-guided radiotherapy (IGRT) protocols to ensure its safe delivery. The aim of this survey was to provide an assessment of current lung SABR practice in the UK.

METHODS

An online semi-structured survey containing a maximum of 32 questions regarding lung SABR, focussing on treatment image verification processes was piloted, developed and disseminated to the radiotherapy managers of 62 National Health Service centres across the UK.

RESULTS

The survey had a 100% complete response from NHS centres. 36 centres (58%) currently deliver lung SABR, with half treating fewer than 50 patients per year. Six centres deliver SABR despite not being commissioned by the NHS to provide this service. There is wide variation in the use of IGRT. Eight different permutations of cone beam CT order within the workflow were reported. Almost half of lung centres (17/36, 47%) believe there is a need to update national image guidance associated with lung SABR, such as the use of 'day zero', mid treatment and post treatment cone beam CTs.

CONCLUSION

Our results demonstrate wide variation in IGRT for lung SABR. There is an opportunity to develop existing IGRT workflows and the optimal approach to image guidance. Further work is required to investigate lung SABR provision and potential barriers to its implementation.

ADVANCES IN KNOWLEDGE

This survey represents the most comprehensive and accurate assessment of lung SABR practice in the UK since the 2014 SABR consortium survey.

Lobectomy versus stereotactic ablative radiotherapy for medically operable patients with stage IA non-small cell lung cancer: A virtual randomized phase III trial stratified by age

BACKGROUND

Although the choice between stereotactic ablative radiotherapy (SABR) and lobectomy for early-stage non-small cell lung cancer (NSCLC) has been debated for years, the two procedures have not yet been directly compared in a randomized trial. We conducted a virtual randomized phase III trial stratified by age to compare the effectiveness of lobectomy and SABR for medically operable patients with stage IA (AJCC eighth) NSCLC using the Markov model analysis.

METHODS

A Markov model was developed to simulate a cohort of patients aged 45-85 years with stage IA NSCLC who had undergone either lobectomy or SABR and were followed up for their remaining lifetime. Each virtual patient was randomly assigned to undergo lobectomy or SABR, and 10 000 patients were allocated to each group. All estimates of the variables were obtained by a systematic review of published articles.

RESULTS

The lobectomy group showed a better life expectancy than the SABR group, in patients under 75 years of age. However, no statistically significant difference was seen in patients 75 years or older. The predicted life expectancy was 9.43 and 8.70 years in 75-year-old patients in the lobectomy and SABR groups, respectively. However, the 95%CI for the difference in life expectancy between the two groups was - 0.06-1.50 years (P = 0.0689).

CONCLUSIONS

The Markov model showed no statistically significant difference in the expected overall survival in stage IA NSCLC patients who were older than 75 years and had undergone SABR or lobectomy.

Stereotactic ablative radiation therapy in lung cancer: an emerging standard

PURPOSE OF REVIEW

Significant advances have been made in the field of stereotactic ablative radiotherapy (SABR) for the treatment of pulmonary neoplasms in recent years. This review aims to summarize recent salient evidence on SABR for early-stage nonsmall cell lung cancer (ES-NSCLC).

RECENT FINDINGS

In medically inoperable patients, SABR remains the standard of care. The optimal SABR dosing regimen is being studied. Comparisons with non-SABR radiotherapy regimens with lower doses per fraction revealed benefit of SABR. In operable patients, no prospective clinical trial comparing SABR and surgery has been completed, although multiple trials are currently underway to address this question. SABR is generally cost-effective and safe in most patients, with preserved patient-reported quality of life. However, increased toxicity with SABR is noted in patients with disease close to, or invading the proximal tracheobronchial tree. Significant SABR-related toxicity and mortality is also reported in patients with coexisting interstitial lung disease. Considerations on pathologic confirmation, surveillance and multiple primaries are also addressed.

SUMMARY

SABR is an effective and safe treatment for inoperable ES-NSCLC. Ongoing trials and comparative effectiveness research will help to clarify SABR's role in various lung cancer indications going forward.

Population-based patterns of treatment and survival for patients with stage I and II non-small cell lung cancer aged 65-74 years and 75 years or older

OBJECTIVES

Insights regarding utilization and survival of surgery and radiotherapy (stereotactic body radiotherapy (SBRT) or conventional radiotherapy (RT)) are lacking for older patients with stage I and II non-small cell lung cancer (NSCLC) in clinical practice.

METHODS

Data from the Netherlands Cancer Registry were retrieved for patients ≥65 years with clinical stage I-II NSCLC in 2010-2015. Descriptive analyses, overall survival (OS), and cox regression were stratified for stage I (n = 8742) and II (n = 3439) and compared age groups (65-74 years vs ≥75 years).

RESULTS

Patients aged 65-74 underwent surgery significantly more often compared to those aged ≥75 (stage I 55% vs 27%; stage II: 65% vs 35%), and received SBRT less often (I: 29% vs 42%; II: 5% vs 11%), conventional RT less often (I: 6% vs 11%; II 10% vs 24%) and best supportive care alone less often (BSC, I: 8% vs 19%; II: 9% vs 25%). One-year OS was significantly higher in patients aged 65-74 compared to those aged ≥75 (I: 87% vs 78%; II: 74% vs 60%); as was five-year OS (I: 49% vs 31%; II: 36% vs 18%). After adjustment for gender, histology, stage, treatment, and comorbidity, hazard ratio (HR) of death was higher for patients aged ≥75 compared to those aged 65-74 (I: HR 1.3, 95% confidence interval (CI) 1.1-1.5; II: HR 1.3 95%CI 1.1-1.7).

CONCLUSION

Patients aged ≥75 with stage I-II NSCLC had poorer OS, underwent surgery less often, and received SBRT, conventional RT, and BSC more often than patients aged 65-74. In both stages, one-year OS within age groups was similar for surgery and SBRT. However, long-term OS adjusted for prognostic factors was superior for surgery compared to SBRT and remained poorer for those aged ≥75. Prospective research should focus on predictive characteristics for treatment selection and patient-centered outcomes.

A Systematic Literature Review on Salvage Radiotherapy for Local or Regional Recurrence After Previous Stereotactic Body Radiotherapy for Lung Cancer

Purpose:

The purpose of this review article was to summarize available data on the efficacy and safety of salvage radiotherapy for isolated local or regional recurrence after prior stereotactic body radiotherapy for lung cancer.

Methods:

Studies were systematically searched on PubMed, following which suitable papers were selected. Reported outcomes and toxicities were qualitatively reviewed.

Results:

Nineteen papers, which were retrospective studies based on single institution experiences, were selected. Sixteen papers were on salvage radiotherapy for local tumor recurrence, and the remaining 3 papers evaluated radiotherapy for regional failures after stereotactic body radiotherapy for lung cancer. Patient cohorts in the selected papers seemed very frail with 2-year survival of 30% to 40% after the salvage. Local control was reported to be approximately 60% to 70%, which is worse than that after primary stereotactic body radiotherapy. Reported rates of toxicity grade 3 or worse were considered acceptable. Larger target volume and central tumor localization were suggested as risk factors for severe toxicities. Dosimetric data on patients having toxicities were found to help with considering dose constraints for organs at risk.

Conclusion:

Based on data from a limited number of articles, salvage radiotherapy is a reasonable treatment option for select patients with local or regional tumor recurrence after prior stereotactic body radiotherapy for lung cancer. Optimal patient selection and dose prescription can be clarified with a larger study that include more data on experiences with salvage radiotherapy.

Survival Rates after Thermal Ablation versus Stereotactic Radiation Therapy for Stage 1 Non-Small Cell Lung Cancer: A National Cancer Database Study

Purpose To compare survival rates of thermal ablation and stereotactic radiation therapy (SRT) for stage 1 non-small cell lung cancer (NSCLC). Materials and Methods In this retrospective study, patients with stage 1 NSCLC treated by thermal ablation (TA) or SRT were identified in the 2004-2013 National Cancer Database. Patients who underwent TA and SRT were one-to-one propensity matched to undergo thermal ablation. Outcomes were overall survival and unplanned hospital readmission within 30 days after treatment. Results This study included 28 834 patients (TA, 1102 patients; SRT, 27 732 patients). Patients treated with TA had more comorbidities (Charlson comorbidity index of 1 vs ≥2, 32.8% [362 of 1102] vs 19.7% [217 of 1102], respectively) compared with SRT (Charlson comorbidity index of 1 vs ≥2, 26.9% [7448 of 27 732] vs 15.3% [4251 of 27 732], respectively; P , .001) and smaller tumor size (mean tumor size, TA vs SRT: 19 mm vs 22 mm, respectively; P , .001). In the propensity score-matched cohort with balanced distribution of potential confounders, there was no significant difference in overall survival between TA and SRT at a mean follow-up of 52.4 months (survival difference, P = .69). Overall survival rates were comparable between TA and SRT (1 year, 85.4% vs 86.3%, respectively, P = .76; 2 years, 65.2% vs 64.5%, respectively, P = .43; 3 years, 47.8% vs 45.9%, respectively, P = .32; 5 years, 24.6% vs 26.1%, respectively, P = .81). Unplanned hospital readmission rates were higher for patients who underwent TA versus those who underwent SRT (3.7% [40 of 1070] vs 0.2% [two of 1070], respectively; P , .001). Conclusion Regarding overall survival, thermal ablation was noninferior to stereotactic radiation therapy for primary treatment of stage 1 non-small cell lung cancer. © RSNA, 2018 Online supplemental material is available for this article. See also the editorial by Shyn in this issue.

Association of Long-term Outcomes and Survival With Multidisciplinary Salvage Treatment for Local and Regional Recurrence After Stereotactic Ablative Radiotherapy for Early-Stage Lung Cancer

Importance

Stereotactic ablative radiotherapy (SABR) is first-line treatment for patients with early-stage non-small cell lung cancer (NSCLC) who cannot undergo surgery. However, up to 1 in 6 such patients will develop isolated local recurrence (iLR) or isolated regional recurrence (iRR). Little is known about outcomes when disease recurs after SABR, or about optimal management strategies for such recurrences.

Objective

To characterize long-term outcomes for patients with iLR or iRR after SABR for early-stage NSCLC with the aim of informing treatment decision making for these patients with potentially curable disease.

Design, Setting, and Participants

In this cohort study, a retrospective review was conducted of 912 patients prospectively enrolled in an institutional database at a tertiary cancer center from January 1, 2004, through December 31, 2014.

Main Outcomes and Measures

Overall survival, progression-free survival, recurrence patterns, demographics, salvage techniques, patterns of salvage failure, and toxic effects.

Results

Of the 912 patients in the study (456 women and 456 men; median age, 72 years [range, 46-91 years]), 756 (82.9%) had T1 tumors at initial diagnosis; 502 tumors (55.0%) were adenocarcinomas and 309 tumors (33.9%) were squamous cell carcinomas. Of 912 patients with early-stage I to II NSCLC who received definitive SABR (50 Gy in 4 fractions or 70 Gy in 10 fractions), 102 developed isolated recurrence (49 with iLR and 53 with iRR), and 658 had no recurrence. Median times to recurrence after SABR were 14.5 months (range, 1.5-60.8 months) for iLR and 9.0 months (range, 1.9-70.7 months) for iRR; 39 of 49 patients (79.6%) with iLR and 48 of 53 patients (90.6%) with iRR underwent salvage with reirradiation, surgery, thermal ablation, or chemotherapy. Median follow-up times for patients with iLR or iRR were 57.2 months (interquartile range, 37.7-87.6 months) from initial SABR and 38.5 months (interquartile range, 19.9-69.3 months) from recurrence. Rates of overall survival at 5 years from initial SABR were no different between patients with iLR and salvage treatment (57.9%) and patients with no recurrence (54.9%; hazard ratio, 0.89; 95% CI, 0.56-1.43; P = .65) but were lower for patients with iRR and salvage treatment (31.1%; hazard ratio, 1.43; 95% CI, 1.00-2.34; P = .049). Patients receiving salvage treatment had longer overall survival than patients who did not (median, 37 vs 7 months after recurrence; hazard ratio, 0.40; 95% CI, 0.09-0.66; P = .006). Twenty-four of 87 patients (27.6%) who received salvage treatment for iLR or iRR subsequently developed distant metastases. No patient experienced grade 5 toxic effects after salvage treatment.

Conclusions and Relevance

Life expectancy after salvage treatment for iLR was similar to that for patients without recurrence, but survival after salvage treatment for iRR was similar to that of patients with stage III NSCLC. Patients who received salvage treatment had significantly improved survival. Because salvage treatment for iLR or iRR was based on a consistent multidisciplinary approach, this may help in clinical decision making.

Is there a room for immune checkpoint inhibitors in early stage non-small cell lung cancer?

Early non-small cell lung cancer (NSCLC) represents 16% of all new NSCLC at diagnosis with a 5-year survival rate of about 60%. Surgical intervention and adjuvant platinum-based chemotherapy represent the cornerstone treatments, but no significant advances have been achieved since several decades in term of relapse rate reduction or survival improvement. Immunotherapy represents an appealing strategy considering the acceptable toxicity profile but, despite the awesome changing recently introduced in the locally advanced and metastatic setting, its role in early NSCLC is not clear yet. In the past few years, two strategies have been investigated to improve the early NSCLC outcomes eliciting the anti-tumour immune response: tumour vaccines and adoptive cellular therapies. However, none of them provided convincing results. Preclinical and clinical data supported the prognostic role of immune checkpoints in resected NSCLC even if they did not show a clear predictive value for adjuvant treatment. However, some preliminary data about safety and efficacy of neo-adjuvant immune checkpoint inhibitors encourage further investigation of their potential role as monotherapy or as part of a multimodal strategy. Then, even if no significant progress has been done in early NSCLC treatment until today, checkpoint inhibitors can open the door to a new strategy in this setting.

Significance of stereotactic body radiotherapy in older patients with early stage non-small cell lung cancer

OBJECTIVES

Our aim was to investigate long-term treatment outcomes in older patients with early stage non-small cell lung cancer (NSCLC) and the presence or absence of therapeutic benefits, using the G8 screening tool.

METHODS

We retrospectively studied 43 older patients (median age 78 years, range 65-89 years) with stage I lung tumors (T1 and T2 tumors in 34 and 9 patients, respectively), who underwent stereotactic body radiotherapy (SBRT). This study assessed outcomes in a cohort of patients who received geriatric assessments, performed between 2004 and 2011, before the start of their SBRT regimen. Any questions asked to patients before undergoing treatment were applied to the G8 screening tool.

RESULTS

G8 scores ranged from 8 to 16 (median, 12) in all patients (n = 43), while G8 scores in the T1 and T2 groups ranged from 9 to 16 (median, 13) and 8 to 15 (median, 12), respectively. In patients with G8 scores ≤12, the 2-year and 5-year survival rates were 56.1% and 28% respectively, while the rates were 94.1% and 68.4%, respectively, in patients with G8 scores ≥13 (P = 0.0014). During long-term follow-up, 25.9% of the patients (n = 43) died of the primary disease, NSCLC, and 34.9% of patients died of other diseases or other types of cancer.

CONCLUSION

SBRT may be effective, even in older adults. Regardless of age, SBRT improved the long-term survival of patients only with G8 scores ≥13. The G8 screening tool may aid in determining whether older patients with comorbidities would benefit from SBRT.

A Retrospective Long-term Follow-up Study of Stereotactic Body Radiation Therapy for Non-Small Cell Lung Cancer From a Single Institution: Incidence of Late Local Recurrence

PURPOSE

To assess the local recurrence (LR) rate and timing after stereotactic body radiation therapy (SBRT) for non-small cell lung cancer using long-term follow-up data from a single institution.

METHODS AND MATERIALS

Patients with primary or recurrent non-small cell lung cancer with or without pathologic verification, with tumors <3 cm, treated with SBRT (isocenter prescription of 48 Gy in 4 fractions) between April 1998 and August 2014, and with >6 months' follow-up were eligible. The LR rate was calculated by the cumulative incidence function, accounting for death as a competing risk. Univariate and multivariate analyses were performed to identify prognostic factors for LR.

RESULTS

A total of 216 patients and 230 tumors were analyzed. The median follow-up time of tumors without LR was 3.9 years, and the crude number of LR cases was 49 (21%). The actuarial rate of LR was 19% (95% confidence interval, 14%-25%) at 5 years. The number of LR cases in each period was 10 in year 1, 17 in year 2, 9 in year 3, 3 in year 4, 3 in year 5, and 7 after 5 years. Among 73 tumors with >5 years' follow-up, we observed 7 late LRs. The tumor histology of these late LRs was adenocarcinoma in 3, squamous cell carcinoma in 2, and unknown in 2 (1 of the unknown cases was confirmed as adenocarcinoma following salvage surgery). The median time to LR was 2.1 years (interquartile range, 1.5-4.2 years) for adenocarcinoma compared with 1.3 years (interquartile range, 1.0-2.3 years) for squamous cell carcinoma. Multivariate analysis revealed that larger tumor size, squamous cell histology compared with adenocarcinoma, and use of abdominal compression for respiratory motion management were independent negative prognostic factors for LR.

CONCLUSIONS

Long-term follow-up data demonstrated that late LR was not uncommon and that careful follow-up after SBRT is needed, especially in patients with adenocarcinoma.

Radiological differential diagnosis between fibrosis and recurrence after stereotactic body radiation therapy (SBRT) in early stage non-small cell lung cancer (NSCLC)

Background

Parenchymal changes after stereotactic body radiation therapy (SBRT) make differential diagnosis between treatment outcomes and disease recurrence often difficult. The purpose of our study was to identify the radiographic features detectable at computed tomography (CT) scan [high-risk features (HRFs)] that allow enough specificity and sensitivity for early detection of recurrence.

Methods

We retrospectively evaluated patients who underwent SBRT for inoperable early stage non-small cell lung cancer (NSCLC). The median delivered dose performed was 50 Gy in 5 fractions prescribed to 80% isodose. All patients underwent chest CT scan before SBRT and at 3, 6, 12, 18, 24 months after, and then annually. Each CT scan was evaluated and benign and HRFs were recorded. ¹⁸F-fluorodeoxyglucose-CT was not used routinely.

Results

Forty-five patients were included (34 males, 11 females; median age: 77 years; stage IA: 77.8%, stage IB: 22.2%; median follow-up: 21.7 months). Two year and actuarial local control was 77%. HRFs were identified in 20 patients. The most significant predictor of relapse was an enlarging opacity at 12 months (P<0.001) with 84.6% sensitivity and 71.8% specificity. The presence of ≥2 HRFs demonstrated a high sensibility (92.3%) and specificity (71.9%) (P<0.0001).

Conclusions

Detection of HRFs is predictive of relapse with a sensibility that increases with the number of HRFs observed. This observation may allow to better define the diagnostic follow algorithm up suggesting to performing further exams only in patients with >2 HRFs.

Radiation therapy-induced metastasis: radiobiology and clinical implications

Radiation therapy is an effective means of achieving local control in a wide range of primary tumours, with the reduction in the size of the tumour(s) thought to mediate the observed reductions in metastatic spread in clinical trials. However, there is evidence to suggest that the complex changes induced by radiation in the tumour environment can also present metastatic risks that may counteract the long-term efficacy of the treatment. More than 25 years ago, several largely theoretical mechanisms by which radiation exposure might increase metastatic risk were postulated. These include the direct release of tumour cells into the circulation, systemic effects of tumour and normal tissue irradiation and radiation-induced changes in tumour cell phenotype. Here, we review the data that has since emerged to either support or refute these putative mechanisms focusing on how the unique radiobiology underlying modern radiotherapy modalities might alter these risks.

Difference in target definition using three different methods to include respiratory motion in radiotherapy of lung cancer

INTRODUCTION

Minimizing the planning target volume (PTV) while ensuring sufficient target coverage during the entire respiratory cycle is essential for free-breathing radiotherapy of lung cancer. Different methods are used to incorporate the respiratory motion into the PTV.

MATERIAL AND METHODS

Fifteen patients were analyzed. Respiration can be included in the target delineation process creating a respiratory GTV, denoted iGTV. Alternatively, the respiratory amplitude (A) can be measured based on the 4D-CT and A can be incorporated in the margin expansion. The GTV expanded by A yielded GTV + resp, which was compared to iGTV in terms of overlap. Three methods for PTV generation were compared. PTV_del (delineated iGTV expanded to CTV plus PTV margin), PTV_σ (GTV expanded to CTV and A was included as a random uncertainty in the CTV to PTV margin) and PTV_∑ (GTV expanded to CTV, succeeded by CTV linear expansion by A to CTV + resp, which was finally expanded to PTV_∑).

RESULTS

Deformation of tumor and lymph nodes during respiration resulted in volume changes between the respiratory phases. The overlap between iGTV and GTV + resp showed that on average 7% of iGTV was outside the GTV + resp implying that GTV + resp did not capture the tumor during the full deformable respiration cycle. A comparison of the PTV volumes showed that PTV_σ was smallest and PTV_Σ largest for all patients. PTV_σ was in mean 14% (31 cm³) smaller than PTV_del, while PTV_del was 7% (20 cm³) smaller than PTV_Σ.

CONCLUSIONS

PTV_σ yields the smallest volumes but does not ensure coverage of tumor during the full respiratory motion due to tumor deformation. Incorporating the respiratory motion in the delineation (PTV_del) takes into account the entire respiratory cycle including deformation, but at the cost, however, of larger treatment volumes. PTV_Σ should not be used, since it incorporates the disadvantages of both PTV_del and PTV_σ.

European Organization for Research and Treatment of Cancer (EORTC) recommendations for planning and delivery of high-dose, high precision radiotherapy for lung cancer

PURPOSE

To update literature-based recommendations for techniques used in high-precision thoracic radiotherapy for lung cancer, in both routine practice and clinical trials.

METHODS

A literature search was performed to identify published articles that were considered clinically relevant and practical to use. Recommendations were categorised under the following headings: patient positioning and immobilisation, Tumour and nodal changes, CT and FDG-PET imaging, target volumes definition, radiotherapy treatment planning and treatment delivery. An adapted grading of evidence from the Infectious Disease Society of America, and for models the TRIPOD criteria, were used.

RESULTS

Recommendations were identified for each of the above categories.

CONCLUSION

Recommendations for the clinical implementation of high-precision conformal radiotherapy and stereotactic body radiotherapy for lung tumours were identified from the literature. Techniques that were considered investigational at present are highlighted.

Salvage surgery after high-dose radiotherapy

Salvage surgery is a relatively new entity in thoracic surgery and oncology. Salvage resection after radiotherapy refers to surgery as only remaining therapeutic option in patients who were treated with high-dose stereotactic radiotherapy (SRT) for early-stage lung cancer or full-dose chemoradiation for locally advanced lung cancer. Indications include locally progressive tumors, recurrent local or locoregional disease, or specific complications after radiotherapy such as lung abscesses or infected, necrotic cavities. Small, retrospective series demonstrate that salvage surgery after high-dose radiotherapy is feasible and may yield good long-term results. A clear distinction should be made between salvage surgery after SRT for early-stage lung cancer and salvage procedures after full-dose chemoradiation for lung cancers with locoregional extension into the mediastinum. Salvage surgery after SRT may be rather straightforward and in specific cases even feasible by a minimally invasive approach. In contrast, surgery after a full dose of chemoradiation delivered several months or years earlier, can be quite challenging and the dissection of the pulmonary artery and mediastinal lymph nodes technically demanding. Due to the more central irradiation an intrapericardial dissection is often required. To prevent a bronchopleural fistula protection of the bronchial stump with well-vascularized flaps is recommended. Each individual patient in whom salvage surgery is considered, should be discussed thoroughly within a multidisciplinary board, detailed cardiopulmonary functional evaluation is required, and the operation should be performed by an experienced team including a thoracic surgeon, anaesthesiologist and intensive care physician. At the present time only retrospective series are available. Carefully designed prospective studies are necessary to more precisely define indications and results of salvage surgery not only after SRT for peripherally localized lesions but also following full-dose chemoradiation for locoregionally advanced disease.

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.

Salvage surgery for local failures after stereotactic ablative radiotherapy for early stage non-small cell lung cancer

Introduction

The literature on surgical salvage, i.e. lung resections in patients who develop a local recurrence following stereotactic ablative radiotherapy (SABR), is limited. We describe our experience with salvage surgery in nine patients who developed a local recurrence following SABR for early stage non-small cell lung cancer (NSCLC).

Methods

Patients who underwent surgical salvage for a local recurrence following SABR for NSCLC were identified from two Dutch institutional databases. Complications were scored using the Dindo-Clavien-classification.

Results

Nine patients who underwent surgery for a local recurrence were identified. Median time to local recurrence was 22 months. Recurrences were diagnosed with CT- and/or 18FDG-PET-imaging, with four patients also having a pre-surgical pathological diagnosis. Extensive adhesions were observed during two resections, requiring conversion from a thoracoscopic procedure to thoracotomy during one of these procedures. Three patients experienced complications post-surgery; grade 2 (N = 2) and grade 3a (N = 1), respectively. All resection specimens showed viable tumor cells. Median length of hospital stay was 8 days (range 5–15 days) and 30-day mortality was 0 %. Lymph node dissection revealed mediastinal metastases in 3 patients, all of whom received adjuvant therapy.

Conclusions

Our experience with nine surgical procedures for local recurrences post-SABR revealed two grade IIIa complications, and a 30-day mortality of 0 %, suggesting that salvage surgery can be safely performed after SABR.

A critical review of recent developments in radiotherapy for non-small cell lung cancer

Lung cancer is the leading cause of cancer mortality, and radiotherapy plays a key role in both curative and palliative treatments for this disease. Recent advances include stereotactic ablative radiotherapy (SABR), which is now established as a curative-intent treatment option for patients with peripheral early-stage NSCLC who are medically inoperable, or at high risk for surgical complications. Improved delivery techniques have facilitated studies evaluating the role of SABR in oligometastatic NSCLC, and encouraged the use of high-technology radiotherapy in some palliative settings. Although outcomes in locally advanced NSCLC remain disappointing for many patients, future progress may come about from an improved understanding of disease biology and the development of radiotherapy approaches that further reduce normal tissue irradiation. At the moment, the benefits, if any, of radiotherapy technologies such as proton beam therapy remain unproven. This paper provides a critical review of selected aspects of modern radiotherapy for lung cancer, highlights the current limitations in our understanding and treatment approaches, and discuss future treatment strategies for NSCLC.

Narcissus, the Beam, and lung cancer

In the management of lung cancer, the rules of engagement of stereotactic ablative radiotherapy (SABR) are not clearly defined. The potential for SABR to affect to an unprecedented level current protocols and in all disease stages emerges vehemently from the literature. However, in a time when the role of surgery is being reassessed, surgeons need to take a closer look at the evidence for the use of SABR in lung cancer patients and clearly define their indisputable role within the context of multidisciplinary teams. The myth of Narcissus exemplified in the absolute masterpiece by Caravaggio seems to represent an ideal metaphor to explain the ever-evolving interaction between surgery and SABR in lung cancer management.