Radical treatment of non-small-cell lung cancer patients with synchronous oligometastases: long-term results of a prospective phase II trial (Nct01282450). J Thorac Oncol. 2012;7:1547-1555. [PMID: 22982655 DOI: 10.1097/jto.0b013e318262caf6]

Role of Local Ablative Therapy in Patients with Oligometastatic and Oligoprogressive Non-Small Cell Lung Cancer

Because of an improved understanding of lung cancer biology and improvement in systemic treatment, an oligometastatic state in which metastatic disease is present at a limited number of anatomic sites is being increasingly recognized. An oligoprogressive state, which is a similar but distinct entity, refers to disease progression at a limited number of anatomic sites, with continued response or stable disease at other sites of disease. Such an oligoprogressive state is best described in patients with NSCLC treated with molecular targeted therapy. Possible explanations for development of the oligoprogressive state include the presence of underlying clonal heterogeneity and extrinsic selection pressure due to the use of targeted therapy. Traditionally, local ablative therapy (LAT) has been limited to symptom palliation in patients with advanced NSCLC, but the presence of oligometastatic or oligoprogressive disease provides a unique opportunity to evaluate the role of LAT such as surgery, radiation therapy, radiofrequency ablation, or cryoablation. There is increasing evidence to support the clinical benefit of LAT in patients with NSCLC with limited metastatic disease and in selected individuals in whom resistance to targeted therapies develops. In the latter instance, adequate treatment of drug-resistant clones by LAT could potentially help in avoiding switching systemic therapy prematurely. This review focuses on the biology of oligometastatic and oligoprogressive NSCLC and describes the role of LAT in the treatment of these conditions.

The IASLC Lung Cancer Staging Project: Proposals for the Revision of the M Descriptors in the Forthcoming Eighth Edition of the TNM Classification of Lung Cancer

INTRODUCTION

The aim of this study is to analyze all metastatic (M) categories of the current tumor, node, and metastasis (TNM) classification of lung cancer with the objective of providing suggestions for modifications of the M component in the next edition of the TNM classification for lung cancer.

METHODS

The new International Association for the Study of Lung Cancer lung cancer database was created from 94,708 patients diagnosed as having lung cancer between 1999 and 2010. Including further patients submitted through the electronic data capture system to Cancer Research and Biostatistics until 2012, all together 1059 non-small-cell lung cancer cases were available for a detailed analysis of the clinical M categories. Overall survival was calculated using the Kaplan-Meier method, and prognosis was assessed using a Cox proportional hazards regression analysis.

RESULTS

No significant differences were found among the M1a (metastases within the chest cavity) descriptors. However, when M1b (distant metastases outside the chest cavity) were assessed according to the number of metastases, tumors with a single metastasis in a single organ had significantly better prognosis than those with multiple metastases in one or several organs.

CONCLUSIONS

In this revision of the TNM classification, cases with pleural/pericardial effusions, contralateral/bilateral lung nodules, contralateral/bilateral pleural nodules, or a combination of multiple of these parameters should continue to be grouped as M1a category. Single metastatic lesions in a single distant organ should be newly designated to the M1b category. Multiple lesions in a single organ or multiple lesions in multiple organs should be reclassified as M1c category. This new division can serve as a first step into providing rational definitions for an oligometastatic disease stage in non-small-cell lung cancer in the future.

Stereotactic body radiotherapy for oligoprogressive cancer

Stereotactic body radiotherapy (SBRT) is a focused tumour treatment that produces high local control rates with low toxicity. Its use in metastatic cancer is evolving rapidly, with purported benefits in the oligometastatic setting and for better palliation of symptomatic disease. Another potential indication for SBRT is in the setting of oligoprogression, where there is progression of a solitary or a few tumours while all other tumours are responding or stable on a systemic therapy strategy. SBRT to the progressing "rogue" tumours may delay the need to start or change systemic therapy. This may have clinical benefits including improved progression-free/overall survival and quality of life for patients. This review will summarize the limited published data. More prospective clinical trials are urgently needed to better identify and quantify the potential clinical benefits.

Clinical applications of stereotactic radiation therapy for oligometastatic cancer patients: a disease-oriented approach

Oligometastases from solid tumors are currently recognized as a distinct clinical entity, corresponding to an intermediate state between local and widespread disease. It has been suggested that local ablative therapies (including surgery, radiofrequency ablation and radiation therapy) play an important role in this setting, in combination or not with systemic therapies, particularly in delaying disease progression and hopefully in increasing the median survival time. Stereotactic body radiation therapy (SBRT) rapidly emerged in recent years as one of the most effective and less toxic local treatment modalities for lung, liver, adrenal, brain and bone metastases. The aim of this review was to focus on its clinical role for oligometastatic disease in four major cancer subtypes: lung, breast, colorectal and prostate. On the basis of the available evidence, SBRT is able to provide high rates of local tumor control without significant toxicity. Its global impact on survival is uncertain; however, in specific subpopulations of oligometastatic patients there is a trend towards a significant improvement in progression-free and overall survival rates; these important data might be used as a platform for clinical decision-making and establish the basis for the current and future prospective trials investigating its role with or without systemic treatments.

The role of local ablative therapy in oligometastatic non-small-cell lung cancer: hype or hope

In recent years, the emergence of the oligometastatic state has called into question whether patients found to have a limited or low metastatic tumor burden may benefit from locally ablative therapy (LAT). In the past two decades, stereotactic body radiation therapy has been increasingly used to safely deliver LAT and provide high local control in nonoperable non-small-cell lung cancer patients. Mostly retrospective analyses suggest that using LAT for oligometastatic disease in non-small-cell lung cancer offers excellent local control and may provide an improvement in progression-free survival. Any meaningful improvement in cancer-specific survival remains debatable. We examine the role of integrating LAT in this patient population and the rationale behind its use in combination with targeted therapy and immunotherapy.

Patterns of Distant Metastases After Surgical Management of Non-Small-cell Lung Cancer

BACKGROUND

Patients with limited metastases, oligometastases (OMs), might have improved outcomes compared with patients with widespread distant metastases (DMs). The incidence and behavior of OMs from non-small-cell lung cancer (NSCLC) need further characterization.

PATIENTS AND METHODS

The medical records of patients who had undergone surgery for stage I-III NSCLC from 1995 to 2009 were retrospectively reviewed. All information pertaining to development of the first metastatic progression was recorded and analyzed. Patients with DMs were categorized into OMs (1-3 lesions potentially amenable to local therapy) and DM subgroups.

RESULTS

Of 1719 patients reviewed, 368 (21%) developed DMs with a median follow-up period of 39 months. A single lesion was diagnosed in 115 patients (31%) and 69 (19%) had 2 to 3 lesions (50% oligometastatic). The median survival from the DM diagnosis for oligometastatic and diffuse DM was 12.4 and 6.1 months, respectively (hazard ratio, 0.54; 95% confidence interval, 0.42-0.68; P < .001). Patients with a single metastasis had the longest median survival at 14.7 months. Younger age, OM, the use of chemotherapy for the primary tumor, and DM detection by surveillance imaging were independently associated with improved survival.

CONCLUSION

DMs and OMs are common in surgically managed NSCLC. Overall survival appears to be prolonged with OM.

PET Imaging of Skeletal Metastases and Its Role in Personalizing Further Management

In oncology, the skeleton is one of the most frequently encountered sites for metastatic disease and thus early detection not only has an impact on an individual patient's management but also on the overall outcome. Multiparametric and multimodal hybrid PET/computed tomography and PET/MR imaging have revolutionized imaging for bone metastases, but irrespective of tumor biology or morphology of the bone lesion it remains unclear which imaging modality is the most clinically relevant to guide individualized cancer care. In this review, we highlight the current clinical challenges of PET imaging in evaluation and quantification of skeletal tumor burden and its impact on personalized cancer management.

Integration of Stereotactic Body Radiation Therapy With Tyrosine Kinase Inhibitors in Stage IV Oncogene-Driven Lung Cancer

: Genotype-based selection of patients for targeted therapies has had a substantial impact on the treatment of non-small cell lung cancers (NSCLCs). Tyrosine kinase inhibitors (TKIs) directed at cancers driven by oncogenes, such as epidermal growth factor receptor mutations or anaplastic lymphoma kinase rearrangements, often achieve dramatic responses and result in prolonged survival compared with chemotherapy. However, TKI resistance invariably develops. Disease progression can be limited to only one or a few sites and might not be symptomatic, raising the important question of whether this type of oligoprogression warrants a change in systemic therapy or consideration of local treatment. Recent clinical observations suggest a growing role for stereotactic body radiation therapy (SBRT) in the treatment of oligoprogressive and perhaps even oligopersistent disease (primary and/or metastases) in oncogene-driven NSCLC. SBRT might allow patients to continue with existing TKI treatments longer and delay the need to switch to other systemic options. We review the current data with regard to the use of SBRT for metastatic NSCLC and particularly oncogene-driven disease. Although there is great promise in the marriage of targeted therapies with SBRT, prospective data are urgently needed. In the meantime, such strategies are being used in carefully selected patients, with risk-adapted SBRT dose-fractionation regimens used to optimize the therapeutic index.

IMPLICATIONS FOR PRACTICE

Stereotactic body radiation therapy (SBRT) or SBRT-like treatments are increasingly being used for oligoprogression in patients with oncogene-driven non-small cell lung cancer. This approach allows patients to extend the duration of tyrosine kinase inhibitor therapy and has the potential to prolong survival times. Careful patient selection and risk-adapted radiation dosing is of critical importance to minimize toxicity and preserve patient quality of life.

Outcomes of a Highly Selective Surgical Approach to Oligometastatic Lung Cancer

BACKGROUND

A highly selected subset of patients with oligometastatic non-small cell lung cancer (NSCLC) will be cured after all sites of established disease (primary and metastases) have been eliminated by surgery or radiation (ie, "curative intent" approach). Mediastinal lymph node metastases (N2) have been found retrospectively to predict a poor prognosis in this setting (5-year survival of 4% for N2-positive versus 31% for N2-negative). Hence, our institution has programmatically limited the use of curative intent local therapy to oligometastatic NSCLC patients confirmed to be free of N2 disease. However, it is unclear whether the exclusion of N2-positive patients is an effective prospective selection step to aggressively treat oligometastatic NSCLC.

METHODS

A prospectively maintained institutional tumor registry was reviewed for oligometastatic stage IV NSCLC patients evaluated for curative intent treatment from 2005 to 2014.

RESULTS

All synchronous oligometastatic NSCLC cases were evaluated by invasive mediastinal staging before treatment. Twenty-two patients without N2 disease underwent curative intent treatment, and 13 patients with N2 disease were treated palliatively. The groups were similar by bivariate analyses. The N2-negative patients treated with curative intent had a superior 5-year survival compared with N2-positive patients treated palliatively (58% versus 0%, respectively; p = 0.028).

CONCLUSIONS

Using invasive mediastinal staging to exclude N2 disease has a role in surgical decision making and achieving long-term survival among oligometastatic NSCLC patients. Further study is warranted to determine whether a subset of patients with N2 disease also have the potential for long-term survival with local therapy.

[Development of Precision Medicine in the Surgical Treatment of Lung Cancer]

精准医学是根据每个人从宏观到微观层面的个体差异，制定最为合适的个性化治疗方案。基因组、蛋白组、代谢组等海量生物学数据及大数据分析方法是精准医学模式的精髓。精准医学为人类攻克肿瘤带来了希望。肺癌是对人类危害最大的肿瘤。本文就肺癌的外科治疗在精准医学时代发展的方向进行了综述。

Radiation Therapy for Oligometastatic Non-Small Cell Lung Cancer: Theory and Practice

Management paradigms for metastatic non-small cell lung cancer (mNSCLC) are evolving. Locally ablative therapies are now being increasingly integrated into combined-modality treatment strategies for mNSCLC patients with limited burdens of metastatic foci, termed oligometastases. Concurrently, techniques allowing for precise high-dose radiotherapy delivered over 1 to 5 total treatments, termed stereotactic body radiation therapy (SBRT) or stereotactic ablative radiation therapy (SABR), have emerged as a powerful means of noninvasive tumor ablation with broad patient candidacy. Strong rationale exists for ablative therapy in the setting of oligometastatic NSCLC, including patterns-of-failure analyses and data supporting local ablation of oligoprogressive disease for patients with oncogene-addicted mNSCLC treated with tyrosine kinase inhibitors. In this article, we examine the theoretical basis for ablation of oligometastatic NSCLC and review the growing clinical literature of mNSCLC patients treated with ablative radiation therapy.

Long-term outcomes in radically treated synchronous vs. metachronous oligometastatic non-small-cell lung cancer

BACKGROUND

Radical treatment for oligometastatic non-small-cell lung cancer (NSCLC) has a curative potential for selected patients. The present retrospective study was designed to examine the relevance of synchronous vs. metachronous manifestations as a potential prognostic factor when ablative treatments are performed in oligometastatic disease.

METHODS

Seventy-five patients with radically treated oligometastatic NSCLC were identified, of whom 39 presented with synchronous and 36 with metachronous metastatic manifestations. For patients with synchronous metastases, an additional therapy of the thoracic locoregional disease with a curative intent (either surgery or radiochemotherapy) was required. All patients with metachronous metastases had a documented remission of the primary tumor. Ablative treatment of the complete extent of oligometastatic disease consisted (as a minimum requirement) of either complete surgical resection or definitive ablative stereotactic radiotherapy. A comparative survival analysis of two groups of patients with oligometastatic NSCLC (synchronous vs. metachronous) and a complementary analysis of prognostic factors for the whole group of patients (by means of Cox regression analysis) was performed. Endpoints were median overall and progression-free survival (OS, PFS, respectively).

RESULTS

Of the 75 patients, 57 presented with a solitary metastasis, in only 7 patients metastastatic lesions were present in ≥2 organs and 66 patients had a Karnofsky performance score (KPS) of 80 % or 90 %. The median follow-up was 54.0 months (95 % CI 28-81), the median OS 21.8 months (16.1-27.6) and the median PFS 13.7 months (9.7-17.6). In univariable Cox regression analysis, no single clinical factor was significantly associated with OS. For PFS both 'metastatic involvement of ≥2 organs vs. 1 organ' (hazard ratio (HR) 0.43, 0.23-0.83, p = 0.012) and a 'KPS of 90 % vs. 70-80 %' (HR 4.32, 1.73-10.89, p = 0.02) were significant prognostic factors as calculated by multivariable analysis. Comparing the cohorts with synchronous (n = 39) vs. metachronous oligometastases (n = 36), no differences in median OS and PFS were found. Both cohorts were well-balanced except for the KPS, which was significantly superior in patients with synchronous oligometastases.

CONCLUSIONS

Radical treatment of oligometastatic NSCLC was associated with acceptable long-term survival rates in patients with good KPS and it was equally effective for synchronous and metachronous manifestations.

Prognostic value of blood-biomarkers related to hypoxia, inflammation, immune response and tumour load in non-small cell lung cancer - A survival model with external validation

AIM

Improve the prognostic prediction of clinical variables for non-small cell lung cancer (NSCLC), by selecting from blood-biomarkers, non-invasively describing hypoxia, inflammation and tumour load.

METHODS

Model development and validation included 182 and 181 inoperable stage I-IIIB NSCLC patients treated radically with radiotherapy (55.2%) or chemo-radiotherapy (44.8%). Least absolute shrinkage and selection operator (LASSO), selected from blood-biomarkers related to hypoxia [osteopontin (OPN) and carbonic anhydrase IX (CA-IX)], inflammation [interleukin-6 (IL-6), IL-8, and C-reactive protein (CRP)], and tumour load [carcinoembryonic antigen (CEA), and cytokeratin fragment 21-1 (Cyfra 21-1)]. Sequent model extension selected from alpha-2-macroglobulin (α2M), serum interleukin-2 receptor (sIL2r), toll-like receptor 4 (TLR4), and vascular endothelial growth factor (VEGF). Discrimination was reported by concordance-index.

RESULTS

OPN and Cyfra 21-1 (hazard ratios of 3.3 and 1.7) significantly improved a clinical model comprising gender, World Health Organization performance-status, forced expiratory volume in 1s, number of positive lymph node stations, and gross tumour volume, from a concordance-index of 0.66 to 0.70 (validation=0.62 and 0.66). Extension of the validated model yielded a concordance-index of 0.67, including α2M, sIL2r and VEGF (hazard ratios of 4.6, 3.1, and 1.4).

CONCLUSION

Improvement of a clinical model including hypoxia and tumour load blood-biomarkers was validated. New immunological markers were associated with overall survival. Data and models can be found at www.cancerdata.org (http://dx.doi.org/10.17195/candat.2016.04.1) and www.predictcancer.org.

Risk factors and management of oligometastatic non-small cell lung cancer

Non-small cell lung cancer (NSCLC) is an aggressive malignancy with close to half of all patients presenting with metastatic disease. A proportion of these patients with limited metastatic disease, termed oligometastatic disease, have been shown to benefit from a definitive treatment approach. Synchronous and metachronous presentation of oligometastatic disease have prognostic significance, with current belief that metachronous disease is more favorable. Surgical excision of intracranial and extracranial oligometastatic disease has been shown to improve survival, especially in patients with lymph node-negative disease, adenocarcinoma histology and smaller thoracic tumors. Definitive radiation to sites of oligometastatic disease and initial thoracic disease has also been shown to have a similar impact on survival for both intracranial and extracranial disease. Recent studies have reported on the use of targeted agents combined with ablative doses of radiation in the oligometastatic setting with promising outcomes. In this review, we present the historical and current literature describing surgical and radiation treatment options for patients with oligometastatic NSCLC.

Curative intent therapy in oligometastatic lung cancer with an unresectable primary with N3 nodes: case report and review of the literature

Untreated NSCLC patients with brain metastases have a median survival of approximately 2 months; locally advanced stage III NSCLC patients treated with chemoradiation have a median survival of 16-19 months. Select patients with oligometastatic disease may have a prolonged survival if managed aggressively. We present the case of a 47-year-old woman with lung adenocarcinoma, cT2aN3M1a, (supraclavicular lymph node, solitary brain metastasis). She underwent brain metastasectomy, whole brain radiation, induction chemotherapy and concurrent chemoradiotherapy. She relapsed in the brain and locoregionally and was treated with brain re-irradiation, and systemic chemotherapy. Her progression-free survival was 32 months and she is alive with recurrent disease 63 months after diagnosis. Systemic therapy is an important tool in the multimodality management of patients with oligometastatic disease.

Approach for oligometastasis in non-small cell lung cancer

Non-small cell lung cancer (NSCLC) harboring a limited number of distant metastases, referred to as the oligometastatic state, has been indicated for surgery for the past several decades. However, whether the strategy of surgical treatment results in a survival benefit for such patients remains controversial. Experientially, however, thoracic surgeons often encounter long-term survivors among surgically resected oligometastatic NSCLC patients. In this article, the current situation of surgical approach and potential future perspective for oligometastatic NSCLC are reviewed.

TELEHEALTH ALLOWS FOR CLINICAL TRIAL PARTICIPATION AND MULTIMODALITY THERAPY IN A RURAL PATIENT WITH STAGE 4 NON-SMALL CELL LUNG CANCER

Oligometastatic non-small cell lung cancer (NSCLC) has a poor prognosis for rural patients with traditional therapies. Implementation of multi-modality systemic therapy in conjunction with surgical resection can dramatically improve overall survival, leading to clinical complete remission. The currently accepted indications for resection in oligometastatic NSCLC include brain and adrenal metastases. Rural populations are known to have disparities in care of complex malignancies and the use of telehealth has been shown to improve outcomes. We present a case of a rural patient with stage IV NSCLC, who was able to participate in two clinical trials, undergo trimodality therapy, and remain disease-free for 18 months, whose care was facilitated via telehealth video conferencing with a tertiary care center.

Stereotactic Body Radiotherapy for Recurrent Unresectable Head and Neck Cancers

Background

Treatment of locoregional, recurrent head and neck cancers following definitive radiotherapy has evolved during the past 30 years. Brachytherapy as well as protracted courses of systemic therapy and chemoradiotherapy result in 12-month survival rates of 40% to 50% but have high rates of severe toxicity. Given the advancements in radiotherapy targeting and delivery, stereotactic body radiotherapy (SBRT) has been investigated as an alternative treatment option with the potential advantages of reduced treatment time and rates of toxicity.

Methods

The authors reviewed prospective trials and retrospective reports from the past decade addressing the management of locoregional, recurrent, previously radiated head and neck cancers, focusing on SBRT.

Results

The body of evidence is growing in support of reirradiation using SBRT for the treatment of recurrent head and neck cancers. The 1-year survival rates associated with SBRT are promising and similar to those seen with chemotherapy alone and concurrent, conventionally fractionated radiotherapy and chemotherapy. Treatment-related adverse events of reirradiation using SBRT are also similar to other palliative therapies. Late carotid rupture is a relatively rare but concerning late toxicity associated with reirradiation using SBRT.

Conclusions

SBRT is a promising treatment for locoregional recurrent head and neck cancers. It also offers a logistical advantage over other palliative treatments, as it only requires 1 to 2 weeks of treatment.

The Response, Outcome and Toxicity of Aggressive Palliative Thoracic Radiotherapy for Metastatic Non-Small Cell Lung Cancer Patients with Controlled Extrathoracic Diseases

Background and Purpose

For metastatic non-small cell lung cancer (NSCLC) patients with controlled extrathoracic disease after systemic treatment, stable or progressive primary lung lesions may cause respiratory symptoms and increase comorbidities. In the present study, we sought to investigate whether aggressive palliative thoracic radiotherapy (RT) can enhance local control and improve the survival for this subgroup of patients.

Materials and Methods

Between March 2006 and December 2014, 56 patients with metastatic NSCLC who had responsive or stable extrathoracic diseases after chemotherapy and/or molecular targets, and received thoracic RT for stable and progressive primary lung lesions were included. RT with a median dose of 55 Gy (range, 40–62 Gy) was administered in 1.8–2.5 Gy fractions to primary lung tumor and regional mediastinal lymph nodes using modern RT technique. Overall survival (OS) from diagnosis, and locoregional progression-free survival (LRPFS), and survival calculated from radiotherapy (OS-RT) were estimated using the Kaplan-Meier method.

Results

There were 37 men and 19 women with a median age of 60 years at diagnosis. The median interval from the diagnosis of metastatic disease to thoracic RT was 8 months. Following thoracic RT, 26 patients (46%) achieved complete or partial response (overall response rate, ORR). Patients with squamous cell carcinoma or poorly-differentiated carcinoma had a higher ORR than those with adenocarcinoma (63% vs. 34%, P = 0.034). EGFR mutations was closely associated with a better ORR (45% vs. 29%, P = 0.284). At a median follow-up time of 44 months, the median OS, LRPFS after RT, and OS-RT were 50 months, 15 months, and 18 months.

Conclusion

Radical palliative throractic RT is safe and might be beneficial for primary lung lesions of metastatic NSCLC patients with controlled extrathoracic diseases.

The role of stereotactic ablative radiotherapy (SBRT) in the management of oligometastatic non small cell lung cancer

Our understanding of metastatic disease has evolved significantly in the last 20 years. Considered strictly a systemic issue, local treatment would only have significant impact in terms of palliation. However, Hellman and Weichselbaum stated that there might be an intermediate state, in which controlling limited metastatic sites could improve oncologic outcomes. This is called an oligometastatic state, a point between locally confined cancer and widespread disease [1,2]. As treatment with chemotherapy alone for non small cell lung cancer (NSCLC) yields median survivals of 8-11 months [3] and minimal chances of long term survival, new strategies are needed to offer better odds for metastatic patients. Outcomes tend to be better in patients with low volume metastatic disease. [4,5], leading us to question whether the oligometastatic group of patients will gain from a more radical treatment paradigm. In this setting, ablative treatments like surgery or SBRT may provide longer survival and better local control times. There is a rationale for the use of ablative local treatments, as most failures after chemotherapy occur at sites initially affected by disease, and these sites could be a source of further dissemination. Also, chemotherapy resistance can adversely impact resolution of metastatic disease [6]. In rare cases, the abscopal effect (an immune effect arising after radiotherapy in non irradiated metastatic sites) has been described [7,8]. In this review article, we address the impact of SBRT in oligometastatic NSCLC, the most relevant prognostic factors, indications and a site specific review. This review will focus on SBRT for extracranial disease as the role for intracranial SBRT is established.

The evolving role of radiotherapy in treatment of oligometastatic NSCLC

Non-small cell lung cancer (NSCLC) patients with metastases limited in site and number, termed oligometastases, may represent a unique subpopulation of advanced NSCLC with improved prognosis. The optimal management of these patients remains unclear with the treatment approach currently undergoing a paradigm shift. The potential benefit of aggressive metastasis directed local treatment with surgery and/or radiotherapy (RT) in combination with systemic therapy is bolstered predominantly by retrospective analyses but also by a growing number of non-randomized prospective studies regarding the use of ablative RT techniques including stereotactic body radiotherapy (SBRT), alternatively termed stereotactic ablative radiotherapy (SABR), directed at the primary tumor (if present) and all metastatic sites. Long-term survival is possible in a subset of patients treated aggressively in this manner. The challenge for the clinical oncology community moving forward is appropriately selecting patients for this treatment approach based on clinical, imaging, and molecular features and increasing enrollment of patients to prospective clinical trials to more definitively determine the added benefit and appropriate timing of aggressive metastasis directed therapy in the oligometastatic setting.

Radical thoracic radiotherapy may provide favorable outcomes for stage IV non-small cell lung cancer

BACKGROUND

This study investigates the outcome of synchronous stage IV non-small cell lung cancer (NSCLC) patients who received radical thoracic radiotherapy (TRT).

METHODS

We retrospectively reviewed the charts of stage IV NSCLC patients treated with TRT between January 2007 and December 2011. Radiotherapy was considered radical if it was the primary therapy with non-symptom driven intent, or consolidation therapy after initial chemotherapy and the biologically equivalent dose ≥53 Gy halted disease progression. The patients' demographics, disease characteristics, and treatment parameters were uniformly collected.

RESULTS

Eighty-one patients were irradiated with radical intent, including 52% with more than five metastatic lesions. The minimum follow-up was 31.5 months for survivors. The median overall survival (OS) was 20.8 months, with three and four-year OS rates of 23% and 18%, respectively. The median progression-free survival (PFS) was 8.2 months, with one and two-year PFS rates of 23% and 9%, respectively. Partial response (PR) after TRT and administration of targeted therapy were predictive of longer OS. The factors associated with favorable PFS included earlier local tunor node stage, absence of concurrent chemotherapy, and post-TRT PR. No correlation was found between the number of metastatic lesions and survival outcome. Incidences of grade ≥2 toxicities in the lung and esophagus were 9% and 26%, respectively.

CONCLUSIONS

Radical TRT may result in advantageous outcomes for selected stage IV NSCLC patients, regardless of the number of metastatic foci. Patients who achieved post-TRT PR attained the best outcomes.

Stereotactic ablative radiotherapy for pulmonary oligometastases and oligometastatic lung cancer

An increasing body of experience suggests that oligometastasis represents a minimal metastatic state with the potential for cure or prolonged survival in selected patients treated with radical local therapy to all identified sites of disease. The main clinical scenarios managed by thoracic oncology specialists are pulmonary oligometastases from primary malignancies of other anatomic sites and primary lung cancer with oligometastases to lung or other organs. Surgery has been a mainstay of treatment in these situations, with remarkably favorable outcomes following pulmonary metastasectomy in well-selected patient cohorts. As with early stage lung cancer in patients who are medically inoperable, stereotactic ablative radiotherapy is emerging as a prominent local treatment option for oligometastatic disease. We review the role and clinical experience of stereotactic ablative radiotherapy for pulmonary oligometastases and oligometastatic lung cancer.

The biology and treatment of oligometastatic cancer

Clinical reports of limited and treatable cancer metastases, a disease state that exists in a transitional zone between localized and widespread systemic disease, were noted on occasion historically and are now termed oligometastasis. The ramification of a diagnosis of oligometastasis is a change in treatment paradigm, i.e. if the primary cancer site (if still present) is controlled, or resected, and the metastatic sites are ablated (surgically or with radiation), a prolonged disease-free interval, and perhaps even cure, may be achieved. Contemporary molecular diagnostics are edging closer to being able to determine where an individual metastatic deposit is within the continuum of malignancy. Preclinical models are on the outset of laying the groundwork for understanding the oligometastatic state. Meanwhile, in the clinic, patients are increasingly being designated as having oligometastatic disease and being treated owing to improved diagnostic imaging, novel treatment options with the potential to provide either direct or bridging therapy, and progressively broad definitions of oligometastasis.

Results of surgical treatment of primary lung cancer with synchronous brain metastases

Introduction

The surgical treatment of non-small cell lung cancer (NSCLC) with synchronous brain matastases is more effective than other therapeutic options, but this management is still controversial.

The aim of the study

The aim of the study was to evaluate the survival of patients after pulmonary resection NSCLC preceded by resection of brain metastases.

Material and methods

From 2007 to 2012, 645 patients underwent pulmonary resection for NSCLC at our department. In 25 of them (3.87%) thoracic surgery was preceded by resection of a single brain metastasis of NSCLC and a PET CT scan. No signs of nodal involvement or distant metastases were detected.

Results

The group consisted of 18 men (72%) and 7 women (28%). Average age was 57.62 years (46-70). In all cases, whole brain radiotherapy (5 × 4 Gy) was performed. The average interval between excision of brain metastasis and lung resection was 31.4 days (27-41). Pneumonectomy was performed in 1, lobectomy/bilobectomy in 17 and wedge resection in 7 cases. Pathological stage N0 was diagnosed in 17, N1 in 5 and N2 in 3 patients. Average survival was 18.68 months (4-74). Survival at 1, 2 and 5 years was 64%, 28% and 28% respectively. Average disease-free survival was 17.52 months. Histological type (p = 0.57) and G (p = 0.82) have no influence on survival. All the patients with hilar lymph node involvement died within 26 months and with mediastinal one within 12 months.

Conclusions

Surgical treatment of patients with NSCLC with synchronous brain metastases may prove beneficial in selected patients after excluding other distant metastases and lymph node involvement.

Definitive dose thoracic radiation therapy in oligometastatic non-small cell lung cancer: A hypothesis-generating study

PURPOSE

A subset of patients with minimal extrathoracic disease may benefit from aggressive primary tumor treatment. We report comparative outcomes in oligometastatic non-small cell lung cancer (NSCLC) treated with and without definitive, conventionally fractionated thoracic radiation therapy.

METHODS AND MATERIALS

We identified consecutive patients with stage IV NSCLC who had an Eastern Cooperative Oncology Group performance status ≤2 and ≤4 total sites of metastatic disease and who had been prescribed ≥50 Gy of thoracic radiation.

RESULTS

Twenty-nine patients with oligometastatic NSCLC were identified between January 2004 and August 2010. Median survival was 22 months from diagnosis. Four patients (14%) experienced pneumonitis greater than or equal to grade 3; 6 (21%) had esophagitis greater than or equal to grade 3. Local control was associated with improved survival (P = .02). In matched subset analysis, median survival was 9 months (P < .01) in patients who received chemotherapy alone. Median time to local failure was 18 versus 6 months (P = .01). On multivariable analysis, radiation (P < .01; odds ratio [OR], 0.33), fewer metastases (P < .01; OR, 2.14), and female sex (P < .01; OR, 0.41) were associated with improved survival.

CONCLUSIONS

Definitive dose radiation therapy may improve survival in a select subset of patients with minimal extrathoracic disease in whom local progression is of primary concern. Prospective trials are needed to further evaluate the role of local control in oligometastatic NSCLC.

To SABR or not to SABR? Indications and contraindications for stereotactic ablative radiotherapy in the treatment of early-stage, oligometastatic, or oligoprogressive non-small cell lung cancer

Stereotactic ablative radiotherapy (SABR) is a highly effective treatment for early-stage non-small cell lung cancer. Although direct comparisons from randomized trials are not available, rates of both primary tumor control and distant metastasis are similar between SABR and surgery. Overall survival is lower after SABR compared with surgery, largely reflecting that a primary selection criterion for SABR has been medical inoperability because of decreased cardiopulmonary function and other comorbidities that lead to decreased survival independent of non-small cell lung cancer. Survival outcomes between SABR and surgery are much more similar in propensity-matched cohorts. Newer potential indications for SABR include treatment of operable patients; of oligometastatic lung cancer, in which SABR has emerged as an alternative to metastasectomy; and of oligoprogressive lung cancer, an attractive concept especially as improved personalized systemic therapies emerge, and prospective trials are currently being conducted in these settings. Although toxicity in modern series is low, SABR is clearly capable of producing fatal complications, and understanding the risk factors and approaches for mitigating them has been emerging in recent years. Thus, appropriate patient selection is a vital, evolving, and controversial topic.

Radiofrequency ablation for ground-glass opacity-dominant lung adenocarcinoma

PURPOSE

To evaluate retrospectively the clinical utility of lung radiofrequency (RF) ablation for the treatment of ground-glass opacity (GGO)-dominant lung adenocarcinoma.

MATERIALS AND METHODS

From August 2004 through May 2012, 33 consecutive patients (14 men and 19 women; mean age, 71.1 y; age range, 46-84 y) with 42 lung tumors having ≥ 50% GGO component received lung RF ablation. The mean maximum tumor diameter was 1.6 cm ± 0.9 (range, 0.7-4.0 cm). Feasibility, safety, local tumor progression, and survival were evaluated.

RESULTS

For the 42 RF sessions, after RF electrodes were placed in each target tumor, planned ablation protocols were completed in all sessions (100%; 42 of 42). No deaths related to the RF procedure occurred. Major and minor complication rates were 4.8% and 23.8%, respectively. Local tumor progression developed in 6 tumors (14.3%; 6 of 42) during a mean follow-up of 42 months ± 23 (range, 5-92 mo). Four of six tumors with local progression were controlled by repeated RF ablation. No evidence of disease was achieved in 31 of 33 patients (93.9%) at the end of the follow-up period. All but one patient (who died of brain hemorrhage) are alive today. Overall and cancer-specific survival rates were 100% and 100% at 1 year, 96.4% (95% confidence interval [CI], 77.5%-99.5%) and 100% at 3 years, and 96.4% (95% CI, 77.5%-99.5%) and 100% at 5 years, respectively.

CONCLUSIONS

Lung RF ablation is a feasible, safe, and useful therapeutic option to control GGO-dominant lung adenocarcinoma.

Targeting tumour hypoxia to prevent cancer metastasis. From biology, biosensing and technology to drug development: the METOXIA consortium

The hypoxic areas of solid cancers represent a negative prognostic factor irrespective of which treatment modality is chosen for the patient. Still, after almost 80 years of focus on the problems created by hypoxia in solid tumours, we still largely lack methods to deal efficiently with these treatment-resistant cells. The consequences of this lack may be serious for many patients: Not only is there a negative correlation between the hypoxic fraction in tumours and the outcome of radiotherapy as well as many types of chemotherapy, a correlation has been shown between the hypoxic fraction in tumours and cancer metastasis. Thus, on a fundamental basis the great variety of problems related to hypoxia in cancer treatment has to do with the broad range of functions oxygen (and lack of oxygen) have in cells and tissues. Therefore, activation-deactivation of oxygen-regulated cascades related to metabolism or external signalling are important areas for the identification of mechanisms as potential targets for hypoxia-specific treatment. Also the chemistry related to reactive oxygen radicals (ROS) and the biological handling of ROS are part of the problem complex. The problem is further complicated by the great variety in oxygen concentrations found in tissues. For tumour hypoxia to be used as a marker for individualisation of treatment there is a need for non-invasive methods to measure oxygen routinely in patient tumours. A large-scale collaborative EU-financed project 2009-2014 denoted METOXIA has studied all the mentioned aspects of hypoxia with the aim of selecting potential targets for new hypoxia-specific therapy and develop the first stage of tests for this therapy. A new non-invasive PET-imaging method based on the 2-nitroimidazole [(18)F]-HX4 was found to be promising in a clinical trial on NSCLC patients. New preclinical models for testing of the metastatic potential of cells were developed, both in vitro (2D as well as 3D models) and in mice (orthotopic grafting). Low density quantitative real-time polymerase chain reaction (qPCR)-based assays were developed measuring multiple hypoxia-responsive markers in parallel to identify tumour hypoxia-related patterns of gene expression. As possible targets for new therapy two main regulatory cascades were prioritised: The hypoxia-inducible-factor (HIF)-regulated cascades operating at moderate to weak hypoxia (<1% O(2)), and the unfolded protein response (UPR) activated by endoplasmatic reticulum (ER) stress and operating at more severe hypoxia (<0.2%). The prioritised targets were the HIF-regulated proteins carbonic anhydrase IX (CAIX), the lactate transporter MCT4 and the PERK/eIF2α/ATF4-arm of the UPR. The METOXIA project has developed patented compounds targeting CAIX with a preclinical documented effect. Since hypoxia-specific treatments alone are not curative they will have to be combined with traditional anti-cancer therapy to eradicate the aerobic cancer cell population as well.

Evaluating the utility of local therapy for oligometastatic lung cancer

SUMMARY 

In patients with metastatic non-small-cell lung cancer, limited metastases are identified as ‘oligometastases’, and such patients are expected to be long-term progression-free, or possibly curable by local control of those lesions. Especially for oligometastatic recurrence after complete resection of the original primary tumor, local treatment should be taken into consideration as a choice of treatment. Oligoprogression after the administration of EGF receptor tyrosine kinase inhibitors for EGFR-mutated non-small-cell lung cancer might also be indicated for local treatment while continuing the EGF receptor tyrosine kinase inhibitor treatment. Since stereotactic radiotherapy delivery is now available, its potential for local control is nearly comparable to that of surgery. These two major modalities of local therapy should be selected for the treatment of oligometastases after carefully considering both the oligometastatic status (organs, number) and patient status.

Propensity score-matched analysis of comprehensive local therapy for oligometastatic non-small cell lung cancer that did not progress after front-line chemotherapy

PURPOSE

To retrospectively analyze factors influencing survival in patients with non-small cell lung cancer presenting with ≤3 synchronous metastatic lesions.

METHODS AND MATERIALS

We identified 90 patients presenting between 1998 and 2012 with non-small cell lung cancer and ≤3 metastatic lesions who had received at least 2 cycles of chemotherapy followed by surgery or radiation therapy before disease progression. The median number of chemotherapy cycles before comprehensive local therapy (CLT) (including concurrent chemoradiation as first-line therapy) was 6. Factors potentially affecting overall (OS) or progression-free survival (PFS) were evaluated with Cox proportional hazards regression. Propensity score matching was used to assess the efficacy of CLT.

RESULTS

Median follow-up time was 46.6 months. Benefits in OS (27.1 vs 13.1 months) and PFS (11.3 months vs 8.0 months) were found with CLT, and the differences were statistically significant when propensity score matching was used (P ≤ .01). On adjusted analysis, CLT had a statistically significant benefit in terms of OS (hazard ratio, 0.37; 95% confidence interval, 0.20-0.70; P ≤ .01) but not PFS (P=.10). In an adjusted subgroup analysis of patients receiving CLT, favorable performance status (hazard ratio, 0.43; 95% confidence interval, 0.22-0.84; P=.01) was found to predict improved OS.

CONCLUSIONS

Comprehensive local therapy was associated with improved OS in an adjusted analysis and seemed to favorably influence OS and PFS when factors such as N status, number of metastatic lesions, and disease sites were controlled for with propensity score-matched analysis. Patients with favorable performance status had improved outcomes with CLT. Ultimately, prospective, randomized trials are needed to provide definitive evidence as to the optimal treatment approach for this patient population.

Stereotactic ablative body radiotherapy combined with immunotherapy: present status and future perspectives

Radiotherapy is along with surgery and chemotherapy one of the prime treatment modalities in cancer. It is applied in the primary, neoadjuvant as well as the adjuvant setting. Radiation techniques have rapidly evolved during the past decade enabling the delivery of high radiation doses, reducing side-effects in tumour-adjacent normal tissues. While increasing local tumour control, current and future efforts ought to deal with microscopic disease at a distance of the primary tumour, ultimately responsible for disease-progression. This review explores the possibility of bimodal treatment combining radiotherapy with immunotherapy.

Radical irradiation of extracranial oligometastases

Advances in radiotherapy planning and delivery have been used to treat patients with limited metastatic disease. With these techniques, high rates of treated metastasis control and low toxicity have been reported. Some patients have long disease-free intervals after radiotherapy similar to those seen after surgical resection. Ongoing studies will determine the benefit of these irradiation techniques to treat limited metastases, identify appropriate candidates, and assist in integrating these treatments into management strategies for specific diseases.

Phase II study of stereotactic body radiotherapy to primary tumor and metastatic locations in oligometastatic nonsmall-cell lung cancer patients

BACKGROUND

Stereotactic body radiotherapy (SBRT) has emerged as a treatment modality in patients presenting with oligometastatic nonsmall-cell lung cancer (NSCLC). SBRT is used as a local consolidative treatment to metastatic disease sites. The majority of patients included in SBRT trials for oligometastatic NSCLC have controlled primary tumors and brain metastases.

PATIENTS AND METHODS

Oligometastatic NSCLC patients with ≤5 metastatic lesions were included in a prospective phase II trial to evaluate efficacy and toxicity of SBRT to all disease sites, primary tumor and metastatic locations. SBRT to a dose of 50 Gy in 10 fractions was delivered. Positron emission tomography-computed tomography (PET-CT) was carried out at baseline and 3 months after SBRT to evaluate the metabolic response rate according to PET Response Criteria in Solid Tumors (PERCIST). The progression-free survival (PFS) and overall survival (OS) were calculated using Kaplan-Meier method from start of chemotherapy or radiotherapy. Side-effects were scored using the National Cancer Institute Common Terminology Criteria for Adverse Events (NCI CTCAE) version 3.0.

RESULTS

Twenty-six patients received SBRT after induction chemotherapy (n = 17) or as a primary treatment (n = 9). Median follow-up was 16.4 months. Overall metabolic response rate was 60% with seven patients (30%) achieving a complete metabolic remission and 7 (30%) a partial metabolic response. Any acute grade 2 toxicity was observed in four patients (15%) and grade 3 pulmonary toxicity in two patients (8%). Median PFS and OS were 11.2 and 23 months. The 1-year PFS and 1-year OS rate were 45% and 67%, respectively.

CONCLUSION

SBRT to all disease sites, primary tumor and metastatic locations, in oligometastatic NSCLC patients produced an acceptable median PFS of 11.2 months.

Imaging techniques for tumour delineation and heterogeneity quantification of lung cancer: overview of current possibilities

Imaging techniques for the characterization and delineation of primary lung tumours and lymph nodes are a prerequisite for adequate radiotherapy. Numerous imaging modalities have been proposed for this purpose, but only computed tomography (CT) and FDG-PET have been implemented in clinical routine. Hypoxia PET, dynamic contrast-enhanced CT (DCE-CT), dual energy CT (DECT) and (functional) magnetic resonance imaging (MRI) hold promise for the future. Besides information on the primary tumour, these techniques can be used for quantification of tissue heterogeneity and response. In the future, treatment strategies may be designed which are based on imaging techniques to optimize individual treatment.

Prognostic significance of genotype and number of metastatic sites in advanced non-small-cell lung cancer

BACKGROUND

TNM stage remains the most important prognostic factor in clinical practice. The 7th edition lung cancer staging system has not considered some important prognostic factors, such as the number of metastatic organ sites and the molecular biologic characterization.

PATIENTS AND METHODS

Using driver gene alternation and tumor burden, advanced NSCLC cases were divided into 3 groups: M1-I group, epidermal growth factor (EGFR)-positive and/or anaplastic lymphoma kinase (ALK)-positive; MI-II, wild-type EGFR and ALK with intrathoracic metastasis or 1 distant metastatic organ with ≤ 3 metastasis lesions; and MI-III, wild-type EGFR and ALK with 1 distant metastatic organ with > 3 metastasis lesions or multiple metastatic organs. Overall survival was comparable between the 7th edition staging system and our category of M descriptors.

RESULTS

A total of 627 patients with stage IV NSCLC newly diagnosed at Guangdong Lung Cancer Institute between January 2009 and July 2012 were enrolled in the present study. The median overall survival (OS) was 22.2 (95% CI, 19.590-24.810), 15.5 (95% CI, 13.176-17.824), and 10.0 (95% CI, 8.033-11.967) months for M1-I, M1-II, and M1-III, respectively (P < .001). According to the 7th edition of the TNM staging system, the median OS of the M1a and M1b groups was 22.8 (95% CI, 19.484-26.116) and 13.7 (95% CI, 11.793-15.607) months, respectively (P < .001). The maximum of the absolute values of the M1 category for our study and the 7th TNM staging system was 5.881 and 5.089, respectively.

CONCLUSION

Advanced NSCLC could potentially be further divided into 3 subgroups according to the genotype and number of metastatic organ sites and metastasis lesions.

Aggressive therapy for patients with non-small cell lung carcinoma and synchronous brain-only oligometastatic disease is associated with long-term survival

OBJECTIVES

Optimal therapy for patients with non-small cell lung carcinoma (NSCLC) presenting with synchronous brain-only oligometastases (SBO) is not well defined. We sought to analyze the effect of differing therapeutic paradigms in this subpopulation.

MATERIALS AND METHODS

We retrospectively analyzed NSCLC patients with 1-4 SBO diagnosed between 1/2000 and 1/2011 at our institution. Patients with T0 tumors or documented Karnofsky Performance Status <70 were excluded. Aggressive thoracic therapy (ATT) was defined as resection of the primary disease or chemoradiotherapy whose total radiation dose exceeded 45 Gy. Cox proportional hazards and competing risks models were used to analyze factors affecting survival and first recurrence in the brain.

RESULTS

Sixty-six patients were included. Median follow-up was 31.9 months. Intrathoracic disease extent included 9 stage I, 10 stage II and 47 stage III patients. Thirty-eight patients received ATT, 28 did not. Patients receiving ATT were younger (median age 55 vs. 60.5 years, p=0.027) but were otherwise similar to those who did not. Receipt of ATT was associated with prolonged median overall survival (OS) (26.4 vs. 10.5 months; p<0.001) with actuarial 2-year rates of 54% vs. 26%. ATT remained associated with OS after controlling for age, thoracic stage, performance status and initial brain therapy (HR 0.40, p=0.009). On multivariate analysis, the risk of first failure in the brain was associated with receipt of ATT (HR 3.62, p=0.032) and initial combined modality brain therapy (HR 0.34, p=0.046).

CONCLUSION

Aggressive management of thoracic disease in NSCLC patients with SBO is associated with improved survival. Careful management of brain disease remains important, especially for those treated aggressively.

Definitive primary therapy in patients presenting with oligometastatic non-small cell lung cancer

PURPOSE

Although palliative chemotherapy is the standard of care for patients with diagnoses of stage IV non-small cell lung cancer (NSCLC), patients with a small metastatic burden, "oligometastatic" disease, may benefit from more aggressive local therapy.

METHODS AND MATERIALS

We identified 186 patients (26% of stage IV patients) prospectively enrolled in our institutional database from 2002 to 2012 with oligometastatic disease, which we defined as 5 or fewer distant metastatic lesions at diagnosis. Univariate and multivariable Cox proportional hazards models were used to identify patient and disease factors associated with improved survival. Using propensity score methods, we investigated the effect of definitive local therapy to the primary tumor on overall survival.

RESULTS

Median age at diagnosis was 61 years of age; 51% of patients were female; 12% had squamous histology; and 33% had N0-1 disease. On multivariable analysis, Eastern Cooperate Oncology Group performance status ≥ 2 (hazard ratio [HR], 2.43), nodal status, N2-3 (HR, 2.16), squamous pathology, and metastases to multiple organs (HR, 2.11) were associated with a greater hazard of death (all P<.01). The number of metastatic lesions and radiologic size of the primary tumor were not significantly associated with overall survival. Definitive local therapy to the primary tumor was associated with prolonged survival (HR, 0.65, P=.043).

CONCLUSIONS

Definitive local therapy to the primary tumor appears to be associated with improved survival in patients with oligometastatic NSCLC. Select patient and tumor characteristics, including good performance status, nonsquamous histology, and limited nodal disease, may predict for improved survival in these patients.

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.