Radical treatment of synchronous oligometastatic non-small cell lung carcinoma (NSCLC): patient outcomes and prognostic factors

Overcoming Resistance to Checkpoint Inhibitors with Combination Strategies in the Treatment of Non-Small Cell Lung Cancer

Lung cancer continues to contribute to the highest percentage of cancer-related deaths worldwide. Advancements in the treatment of non-small cell lung cancer like immune checkpoint inhibitors have dramatically improved survival and long-term disease response, even in curative and perioperative settings. Unfortunately, resistance develops either as an initial response to treatment or more commonly as a progression after the initial response. Several modalities have been utilized to combat this. This review will focus on the various combination treatments with immune checkpoint inhibitors including the addition of chemotherapy, various immunotherapies, radiation, antibody-drug conjugates, bispecific antibodies, neoantigen vaccines, and tumor-infiltrating lymphocytes. We discuss the status of these agents when used in combination with immune checkpoint inhibitors with an emphasis on lung cancer. The early toxicity signals, tolerability, and feasibility of implementation are also reviewed. We conclude with a discussion of the next steps in treatment.

Integrative Approaches in Non-Small Cell Lung Cancer Management: The Role of Radiotherapy

Treatment guidelines for non-small cell lung cancer (NSCLC) vary by several factors including pathological stage, patient candidacy, and goal of treatment. With many therapeutics and even more combinations available in the NSCLC clinician's toolkit, a multitude of questions remain unanswered vis-a-vis treatment optimization. While some studies have begun exploring the interplay among the many pillars of NSCLC treatment-surgical resection, radiotherapy, chemotherapy, and immunotherapy-the vast number of combinations and permutations of different therapy modalities in addition to the modulation of each constituent therapy leaves much to be desired in a field that is otherwise rapidly evolving. Given NSCLC's high incidence and lethality, the experimentation of synergistic benefits that combinatorial treatment may confer presents a ripe target for advancement and increased understanding without the cost and burden of novel drug development. This review introduces, synthesizes, and compares prominent NSCLC therapies, placing emphasis on the interplay among types of therapies and the synergistic benefits some combinatorial therapies have demonstrated over the past several years.

Resection of the Primary Tumor and Survival in Patients with Single-Site Synchronous Oligometastatic Non-Small Cell Lung Cancer: Propensity-Matched Analysis of the National Cancer Database

BACKGROUND

Local therapy for the primary tumor is postulated to remove resistant cancer cells as well as immunosuppressive cells from the tumor microenvironment, potentially improving response to systemic therapy (ST). We sought to determine whether resection of the primary tumor was associated with overall survival (OS) in a multicentric cohort of patients with single-site synchronous oligometastatic non-small cell lung cancer.

STUDY DESIGN

Using the National Cancer Database (2018 to 2020), we evaluated patients with clinical stage IVA disease who received ST and stratified the cohort based on receipt of surgery for the primary tumor (S). We used multivariable and propensity score-matched analysis to study factors associated with S (logistic regression) and OS (Cox regression and Kaplan-Meier), respectively.

RESULTS

Among 12,215 patients identified, 2.9% (N = 349) underwent S and 97.1% (N = 11,886) ST (chemotherapy or immunotherapy) without surgery. Patients who underwent S were younger, more often White, had higher income levels, were more likely to have private insurance, and were more often treated at an academic facility. Among those who received S, 22.9% (N = 80) also underwent resection of the distant metastatic site. On multivariable analysis, metastasis to bone, N+ disease, and higher T-stages were independently associated with less S. On Cox regression, S and resection of the metastatic site were associated with improved survival (hazard ratio 0.67, 95% CI 0.56 to 0.80 and hazard ratio 0.80, 95% CI 0.72 to 0.88, respectively). After propensity matching, OS was improved in patients undergoing S (median 36.8 vs 20.8 months, log-rank p < 0.001).

CONCLUSIONS

Advances in ST for non-small cell lung cancer may change the paradigm of eligibility for surgery. This study demonstrates that surgical resection of the primary tumor is associated with improved OS in selected patients with single-site oligometastatic disease.

Measured Steps: Navigating the Path of Oligoprogressive Lung Cancer with Targeted and Immunotherapies

PURPOSE OF REVIEW

This review discusses the definitions, treatment modalities, management, future directions, and ongoing clinical trials of oligoprogressive disease in oncogene-driven and non-oncogene-driven NSCLC.

RECENT FINDINGS

During the last decades, diagnostic and treatment modalities for oligometastatic NSCLC have advanced significantly, leading to improved survival. Additionally, our understanding of the tumor biology of oligoprogressive disease has expanded. However, despite the efforts of organizations, such as EORTC, ESTRO, and ASTRO proposing definitions for oligometastatic and oligoprogressive disease, heterogeneity in definitions persists in (ongoing) trials. Recognizing the significance of subclassification within oligoprogressive disease in NSCLC and the varying risks associated with subsequent metastatic spread, there is a call for tailored management strategies. A consensus on standardized criteria for the definition of oligoprogressive disease is urgently needed and will not only facilitate meaningful comparisons between studies but also pave the way for the development of personalized treatment plans that take into account the heterogeneous nature of oligoprogressive disease.

Radiotherapy to reinvigorate immunotherapy activity after acquired resistance in metastatic non-small-cell lung cancer: A pooled analysis of two institutions prospective phase II single arm trials

AIM

The current work aimed to investigate the clinical benefit of radiotherapy in patients with metastatic non-small cell lung cancer (NSCLC) developing acquired resistance to immune checkpoint inhibitors.

METHOD

We report on a pooled, two-institution, phase II single-arm prospective cohort study. The study included patients with stage IV NSCLC who showed progression of one or more measurable lesions under anti-PD-(L)1 inhibition alone, after initially having achieved at least stable disease. Hypofractionated radiotherapy (hRT) of one to four metastases was performed, while one or more lesions were kept untreated. Following hRT, treatment with immune checkpoint inhibitors was continued unchanged until further evidence of tumor progression or unacceptable toxicity. Primary endpoint of the pooled analysis was progression-free survival (PFS), secondary endpoints included overall survival (OS) and toxicity.

RESULTS

A total of 48 patients were enrolled: mean age was 67.1 ± 9.3 years, 50 % were male and 72.9 % were PD-L1 positive. Immunotherapy was in 95.8 % of patients the first or second line therapy at time of enrollment. hRT was performed to one (93.8 % of cases) or more lesions (median total dose: 27.5 Gy, median 6.5 Gy/fraction). Forty-five patients (93.8 %) were able to continue immunotherapy for a median of 6.2 months following hRT. Median PFS was 4.4 months, with 62.5 % disease control at three months and 37.5 % at six months. Median OS was 14.9 months. Severe adverse events (grade ≥ 2) were reported in 12 cases (25 %), of which none were radiotherapy-related and four were immunotherapy-related. Salvage therapy consisted of chemotherapy (48.8 %) or repeated irradiation (21.9 %). No further tumor treatment was performed in 29.3 % of patients.

CONCLUSIONS

The current pooled analysis is a prospective evaluation of the role of radiation therapy for metastatic NSCLC in the setting of newly acquired immunotherapy resistance. Hypofractionated radiotherapy can support the outcome of immune checkpoint inhibitors and thus allow continuation of treatment for a relevant amount of time despite initial tumor progression.

Multimodal treatment of oligometastatic non-small cell lung cancer

The management of patients with oligometastatic non-small cell lung cancer has undergone significant improvement in recent years. The combination of increase in sensitivity of diagnostic tests, development in systemic therapies, surgical techniques and radiotherapy allowing radical ablative treatment of metastases have significantly influenced the treatment of advanced lung cancer, mainly in the patients in which these treatment modalities converge.We report a rare case of a young patient with an oligometastatic lung adenocarcinoma with a single synchronous brain metastasis, who underwent aggressive locoregional and systemic therapies and is still in annual follow-up with excellent quality of life and progression-free survival of 164 months.

Invasive mucinous adenocarcinoma of the lung revealed by a subcutaneous metastasis: A case report of a rare presentation

INTRODUCTION

Lung cancer stands as the second most prevalent tumour and the foremost cause of cancer-related mortality. It typically manifests through respiratory symptoms. Subcutaneous metastases originating from pulmonary cancers are rare occurrences, with a remarkably low incidence.

PRESENTATION OF CASE

A 53-year-old patient, with a history of smoking and unchecked chronic obstructive pulmonary disease, sought care at our outpatient clinic due to the rapid development of a subcutaneous mass. The patient underwent surgical excision of the mass under local anaesthesia. The anatomopathological examination confirmed the diagnosis of cutaneous metastasis from an infiltrative adenocarcinoma. A whole-body CT scan revealed an invasive mucinous adenocarcinoma of the lung. Consequently, palliative chemotherapy was initiated. Unfortunately, the patient succumbed to the disease three months later.

DISCUSSION

Subcutaneous metastasis originating from pulmonary sources is a rare phenomenon, with scant literature available on the subject. The presence of pulmonary cutaneous metastasis serves as an ominous sign of rapidly progressing and aggressive lung cancer. The prognosis in such cases is reserved, with an overall survival rate measured in months. The approach to management in these instances predominantly revolves around palliative chemotherapy, although surgical excision of metastases may be considered in select cases.

CONCLUSION

Lung cancer unmasked by subcutaneous metastasis represents a rare clinical scenario. While chemotherapy remains the cornerstone of treatment, surgical intervention to remove metastases may be contemplated in a restricted subset of cases. Further research is imperative to ascertain the impact of surgery on both quality of life and overall survival.

Unravelling oligometastatic disease from the perspective of radiation and medical oncology. Part I: non-small cell lung cancer and breast cancer

Oligometastatic disease (OMD) defines a cancer status that is intermediate between localized and widely spread metastatic disease, and can be treated with curative intent. While diagnostic imaging tools have considerably improved in recent years, unidentified micrometastases can still evade current detection techniques, allowing the disease to progress. The various OMD scenarios are mainly defined by the number of metastases, the biological and molecular tumour profiles, and the timing of the development of metastases. Increasing knowledge has contributed to the earlier and improved detection of OMD, underlining the importance of early disease control. In view of increasing OMD detection rates in current real-world clinical practice and the lack of standardized evidence-based guidelines to treat this cancer status, a board of experts from the Spanish Societies of Radiation Oncology (SEOR) and Medical Oncology (SEOM) organized a series of sessions to update the current state-of-the-art on OMD from a multidisciplinary perspective, and to discuss how results from clinical studies might translate into promising treatment options. This expert review series summarizes what is known and what it is pending clarification in the context of OMD in the scenarios of non-small cell lung cancer and breast cancer (Part I), and prostate cancer and colorectal cancer (Part II), aiming to offer specialists a pragmatic framework to help improve patient management.

Solitary Uncommon Metastasis in Non-Small Cell Lung Cancer

The major sites of metastasis in non-small cell lung cancer (NSCLC) are bones, the brain, adrenal glands, the liver, the contralateral lung, and distant lymph nodes. Solitary metastasis in an uncommon site is very rare; therefore, it has not often been reported. Identifying whether a solitary lesion is a metastatic lesion is important because it decisively influences the stage and treatment decisions. We report a series of cases of NSCLC diagnosis with uncommon solitary metastasis. (1) A 71-year-old man was diagnosed with poorly differentiated NSCLC after a bronchoscopic biopsy of a tumor in the bronchus of the right middle lobe. A hypermetabolic lesion was observed in the tail of the pancreas using positron emission tomography/computed tomography (PET/CT), and metastasis of NSCLC was confirmed using endoscopic ultrasound fine-needle aspiration (EUS-FNA). (2) A 77-year-old man was diagnosed with squamous cell carcinoma after a bronchoscopic biopsy of a tumor in the bronchus of the left upper lobe. A hypermetabolic lesion was observed in the bilateral lobes of the thyroid gland using PET/CT, and metastasis of the squamous cell carcinoma was confirmed by FNA and cytology. (3) A 79-year-old woman was diagnosed with adenocarcinoma by brushing cytology performed on the apicoposterior segmental bronchus of the left upper lobe. Hypermetabolic lesions were observed using PET/CT in the subcutaneous layer of the right back and the left breast, and metastases of adenocarcinoma were confirmed by biopsies in each lesion. These three patients were treated with platinum-based chemotherapy for stage IV lung cancer. With this case series, we recommend that, when a solitary lesion is observed in NSCLC patients, a tissue biopsy should be performed, even if the lesion is located in an organ where lung cancer metastasis is uncommon.

Prognostic factors in nonsmall cell lung cancer: insights from the German CRISP registry

INTRODUCTION

Understanding prognosis, especially long-term outcome, in advanced nonsmall cell lung cancer (NSCLC) is crucial to inform patients, guide treatment and plan supportive and palliative care.

METHODS

Prognostic factors influencing overall survival (OS) and progression-free survival (PFS) in 2082 patients with wild-type (WT)-NSCLC (629 M1a, 249 M1b, 1204 M1c) are reported. Patients were included in the prospective German CRISP registry recruiting in >150 centres. Analysis for pre-therapeutic factors was based on results from Cox proportional hazard models.

RESULTS

Current M-descriptors of the Union for International Cancer Control-8 staging system were validated: M1a and M1b patients had significantly longer median time to events compared to M1c (OS/PFS 16.4/7.2 months, 17.8/6.7 months and 10.9/5.4 months, respectively). OS and PFS were influenced by number and location of metastatic organ systems. M1c and four or more metastatic organs involved had shorter OS and PFS than M1c with one to three organs (OS hazard ratio (HR) 1.69, p<0.001; PFS HR 1.81, p<0.001). M1b-liver metastases had shorter OS/PFS than M1b involving other organs (OS HR 2.70, p=0.006; PFS HR 2.48, p=0.007). Based on number of involved organs (orgsys) and liver metastases, two risk groups (low-risk: M1a, M1b-non-liver, M1c-1-3-orgsys-non-liver; high-risk: M1c-liver, M1b-liver, M1c-4+-orgsys) with significantly different prognoses could be amalgamated (median OS/PFS 14.3/6.5 months and 7.7/4.1 months, respectively). Other favourable factors were female gender and Eastern Cooperative Oncology Group stage 0, with age showing no impact. Those with T1- or N0-status were associated with longer OS than T2-4 or N2-3.

CONCLUSION

In this large observational dataset, we further defined factors for outcome in WT-NSCLC, including increased number of involved metastatic organ systems and liver metastases, as those with overall poorer prognosis and reduced survival chance.

Local thermal ablative therapies for extracranial oligometastatic disease of non-small-cell lung cancer

Non-small cell lung cancer (NSCLC) is the most common type of lung cancer. Clinically, 40-50% of patients with NSCLC are found to have systemic metastasis at the initial diagnosis. Meanwhile, 30-75% of patients with lung cancer who have undergone radical surgical resection have local recurrence and distant metastases. However, not all distant metastases are multiple, and some are potentially curable. In this study, among the patients with NSCLC having distant organ metastasis, approximately 7% showed extrapulmonary solitary metastasis and remained in this relatively stable state for a long time. This form of metastasis is known as NSCLC oligometastases. This review describes the concept and classification of oligometastases, as well as the local treatment and prognosis of extracranial oligometastases.

Association of Brain Metastases With Survival in Patients With Limited or Stable Extracranial Disease: A Systematic Review and Meta-analysis

IMPORTANCE

Intracranial metastatic disease (IMD) is a severe complication of cancer with profound prognostic implications. Patients with IMD in the setting of limited or stable extracranial disease (IMD-SE) may represent a unique and understudied subset of patients with IMD with superior prognosis.

OBJECTIVE

To evaluate overall survival (OS), progression-free survival (PFS), and intracranial PFS (iPFS) in patients with IMD-SE secondary to any primary cancer.

DATA SOURCES

Records were identified from MEDLINE, EMBASE, CENTRAL, and gray literature sources from inception to June 21, 2021.

STUDY SELECTION

Studies in English reporting OS, PFS, or iPFS in patients with IMD-SE (defined as IMD and ≤2 extracranial metastatic sites) and no prior second-line chemotherapy or brain-directed therapy were selected.

DATA EXTRACTION AND SYNTHESIS

Author, year of publication, type of study, type of primary cancer, and outcome measures were extracted. Random-effects meta-analyses were performed to estimate effect sizes, and subgroup meta-analysis and metaregression were conducted to measure between-study differences in February 2022.

MAIN OUTCOMES AND MEASURES

The primary end point was OS described as hazard ratios (HRs) and medians for comparative and single-group studies, respectively. Secondary end points were PFS and iPFS.

RESULTS

Overall, 68 studies (5325 patients) were included. IMD-SE was associated with longer OS (HR, 0.52; 95% CI, 0.39-0.70) and iPFS (HR, 0.63; 95% CI, 0.52-0.76) compared with IMD in the setting of progressive extracranial disease. The weighted median OS estimate for patients with IMD-SE was 17.9 months (95% CI, 16.4-22.0 months), and for patients with IMD-PE it was 8.0 months (95% CI, 7.2-12.8 months). Pooled median OS for all patients with IMD-SE was 20.9 months (95% CI, 16.35-25.98 months); for the subgroup with breast cancer it was 20.2 months (95% CI, 10.43-38.20 months), and for non-small cell lung cancer it was 27.5 months (95% CI, 18.27-49.66 months). Between-study heterogeneity for OS and iPFS were moderate (I2 = 56.5%) and low (I2 = 0%), respectively.

CONCLUSIONS AND RELEVANCE

In this systematic review and meta-analysis of patients with IMD-SE, limited systemic disease was associated with improved OS and iPFS. Future prospective trials should aim to collect granular information on the extent of extracranial disease to identify drivers of mortality and optimal treatment strategies in patients with brain metastases.

Local therapy treatment conditions for oligometastatic non-small cell lung cancer

Standard treatments for patients with metastatic non-small cell lung cancer (NSCLC) include palliative chemotherapy and radiotherapy, but with limited survival rates. With the development of improved immunotherapy and targeted therapy, NSCLC prognoses have significantly improved. In recent years, the concept of oligometastatic disease has been developed, with randomized trial data showing survival benefits from local ablation therapy (LAT) in patients with oligometastatic NSCLC (OM-NSCLC). LAT includes surgery, stereotactic ablation body radiation therapy, or thermal ablation, and is becoming an important treatment component for OM-NSCLC. However, controversy remains on specific management strategies for the condition. In this review, we gathered current randomized trial data to analyze prognostic factors affecting patient survival, and explored ideal treatment conditions for patients with OM-NSCLC with respect to long-term survival.

Radiotherapy combined with immunotherapy: the dawn of cancer treatment

Radiotherapy (RT) is delivered for purposes of local control, but can also exert systemic effect on remote and non-irradiated tumor deposits, which is called abscopal effect. The view of RT as a simple local treatment has dramatically changed in recent years, and it is now widely accepted that RT can provoke a systemic immune response which gives a strong rationale for the combination of RT and immunotherapy (iRT). Nevertheless, several points remain to be addressed such as the interaction of RT and immune system, the identification of the best schedules for combination with immunotherapy (IO), the expansion of abscopal effect and the mechanism to amplify iRT. To answer these crucial questions, we roundly summarize underlying rationale showing the whole immune landscape in RT and clinical trials to attempt to identify the best schedules of iRT. In consideration of the rarity of abscopal effect, we propose that the occurrence of abscopal effect induced by radiation can be promoted to 100% in view of molecular and genetic level. Furthermore, the “radscopal effect” which refers to using low-dose radiation to reprogram the tumor microenvironment may amplify the occurrence of abscopal effect and overcome the resistance of iRT. Taken together, RT could be regarded as a trigger of systemic antitumor immune response, and with the help of IO can be used as a radical and systemic treatment and be added into current standard regimen of patients with metastatic cancer.

Role of stereotactic body radiotherapy in gynecologic radiation oncology

Stereotactic body radiotherapy (SBRT, also referred to as stereotactic ablative radiotherapy (SABR)) has been used in the treatment of primary and metastatic solid tumors, and increasingly so in gynecologic oncology. This review article aims to summarize the current literature describing the utility of SBRT in the primary, recurrent, and limited metastatic settings for gynecologic malignancies. The use of SBRT in both retrospective and prospective reports has been associated with adequate control of the treated site, particularly in the setting of oligometastatic disease. It is not, however, recommended as an alternative to brachytherapy for intact disease unless all efforts to use brachytherapy are exhausted. While phase I and II trials have established the relative safety and potential toxicities of SBRT, there remains a dearth of phase III randomized evidence, including the use of immunotherapy, in order to better establish the role of this technique as a method of improving more global outcomes for our patients with gynecologic cancers.

Oligometastatic Disease in Non-Small-Cell Lung Cancer: An Update

Simple Summary

Approximately 7–50% of patients with non-small-cell lung cancer (NSCLC) develop oligometastases, which are new tumors found in another part of the body, arising from cancer cells of the original tumor that have travelled through the body. In recent years, these patients have been increasingly regarded as a distinct group that could benefit from treatment that intends to cure the disease, rather than palliative care, to achieve a better clinical outcome. Various treatment procedures have been developed for treating NSCLC patients with different oligometastatic sites. In addition, the newly proposed uniform definition for oligometastases as well as ongoing trials may lead to increased appropriate patient selection and evaluation of treatment effectiveness. The aim of this review article is to summarize the latest evidence regarding optimal management strategies for NSCLC patients with oligometastases.

Abstract

Oligometastatic non-small-cell lung cancer (NSCLC) is a distinct entity that is different from localized and disseminated diseases. The definition of oligometastatic NSCLC varies across studies in past decades owing to the use of different imaging modalities; however, a uniform definition of oligometastatic NSCLC has been proposed, and this may facilitate trial design and evaluation of certain interventions. Patients with oligometastatic NSCLC are candidates for curative-intent management, in which local ablative treatment, such as surgery or stereotactic radiosurgery, should be instituted to improve clinical outcomes. Although current guidelines recommend that local therapy for thoracic and metastatic lesions should be considered for patients with oligometastatic NSCLC with stable disease after systemic therapy, optimal management strategies for different oligometastatic sites have not been established. Additionally, the development of personalized therapies for individual patients with oligometastatic NSCLC to improve their quality of life and overall survival should also be addressed. Here, we review relevant articles on the management of patients with oligometastatic NSCLC and categorize the disease according to the site of metastases. Ongoing trials are also summarized to determine future directions and expectations for new treatment modalities to improve patient management.

Definitive Chemoradiotherapy Results in Synchronous Oligometastatic Non-small Cell Lung Cancer Patients: Turkish Society for Radiation Oncology Group Study (TROD 10-003)

OBJECTIVE

It is aimed to investigate the survival outcomes and prognostic factors after curative treatment of patients diagnosed with synchronous oligometastatic non-small cell lung carcinoma.

MATERIALS AND METHODS

Fifty-two patients from 3 centers diagnosed between 2014 and 2019 were analyzed. The treatment results of thoracic and oligometastatic regions were retrospectively evaluated. The Kaplan-Meier method was used to determine the overall survival (OS) and progression-free survival (PFS) and log-rank tests for the factors affecting survival. Cox regression analysis was employed for multivariate analysis.

RESULTS

Of the 52 patients, 46 (88%) had <2 organ involvement at diagnosis. Treatment of oligometastasis was radiotherapy (RT) in 37, surgery in 4, and surgery with RT in 11 patients. Median 60 Gy were administered to the thoracic tumor. Median RT dose for oligometastasis was 30 Gy in median 5 fractions with either stereotactic body radiation therapy or conventional RT. The median follow-up was 18 months. The median OS and PFS were 35 and 20 months, respectively. The 1-, 2-, and 3-year OS rates were 80.5%, 60.2%, and 41.2%, while the corresponding PFS rates were 75%, 42.5%, and 21.5%, respectively. Multivariate Cox regression analysis revealed that the Eastern Cooperative Oncology Group performance status of "0" and thoracic RT dose over 60 Gy were significant prognostic factors for both the OS and PFS.

CONCLUSIONS

Definitive chemoradiotherapy to the thoracic tumor and treatment of oligometastasis region indicate promising survival outcomes.

A Promising Treatment Strategy for Lung Cancer: A Combination of Radiotherapy and Immunotherapy

Lung cancer is a leading cause of cancer-related deaths worldwide despite advances in treatment. In the past few decades, radiotherapy has achieved outstanding technical advances and is being widely used as a definitive, prophylactic, or palliative treatment of patients with lung cancer. The anti-tumor effects of radiotherapy are considered to result in DNA damage in cancer cells. Moreover, recent evidence has demonstrated another advantage of radiotherapy: the induction of anti-tumor immune responses, which play an essential role in cancer control. In contrast, radiotherapy induces an immunosuppressive response. These conflicting reactions after radiotherapy suggest that maximizing immune response to radiotherapy by combining immunotherapy has potential to achieve more effective anti-tumor response than using each alone. Immune checkpoint molecules, such as cytotoxic T-lymphocyte-associated protein 4, programmed cell death-1/programmed death-ligand 1, and their inhibitors, have attracted significant attention for overcoming the immunosuppressive conditions in patients with cancer. Therefore, the combination of immune checkpoint inhibitors and radiotherapy is promising. Emerging preclinical and clinical studies have demonstrated the rationale for these combination strategies. In this review, we outlined evidence suggesting that combination of radiotherapy, including particle therapy using protons and carbon ions, with immunotherapy in lung cancer treatment could be a promising treatment strategy.

Patient Selection for Local Aggressive Treatment in Oligometastatic Non-Small Cell Lung Cancer

Simple Summary

Since the first introduction of the oligometastatic state with a low burden of metastases in non-small cell lung cancer, accumulating evidence from retrospective and prospective studies has shown that a local aggressive, multimodality treatment may significantly improve the prognosis in these patients. Local aggressive treatment includes a systemic therapy of micrometastatic disease, as well as a radical resection of the primary tumor and surgical resection and/or radiation therapy of distant metastases. However, patient selection and treatment allocation remain a central challenge in oligometastatic disease. In this review, we aimed to address the current evidence on criteria for patient selection for local aggressive treatment in non-small cell lung cancer.

Abstract

One-fourth of all patients with metastatic non-small cell lung cancer presents with a limited number of metastases and relatively low systemic tumor burden. This oligometastatic state with limited systemic tumor burden may be associated with remarkably improved overall and progression-free survival if both primary tumor and metastases are treated radically combined with systemic therapy. This local aggressive therapy (LAT) requires a multidisciplinary approach including medical oncologists, radiation therapists, and thoracic surgeons. A surgical resection of the often advanced primary tumor should be part of the radical treatment whenever feasible. However, patient selection, timing, and a correct treatment allocation for LAT appear to be essential. In this review, we aimed to summarize and discuss the current evidence on patient selection criteria such as characteristics of the primary tumor and metastases, response to neoadjuvant or first-line treatment, molecular characteristics, mediastinal lymph node involvement, and other factors for LAT in oligometastatic NSCLC.

Management of brain metastases in lung cancer: evolving roles for radiation and systemic treatment in the era of targeted and immune therapies

Brain metastases are a common occurrence in both non-small cell and small cell lung cancer with the potential to affect quality of life and prognosis. Due to concerns about the accessibility of the central nervous system by systemic chemotherapy agents, the management of brain metastases has historically relied on local therapies including surgery and radiation. However, novel targeted and immune therapies that improve overall outcomes in lung cancer have demonstrated effective intracranial activity. As a result, the management of brain metastases in lung cancer has evolved, with both local and systemic therapies now playing an important role. Factors such as tumor histology (non-small versus small cell), oncogenic driver mutations, and symptom burden from intracranial disease impact treatment decisions. Here, we review the current management of brain metastases in lung cancer, highlighting the roles of stereotactic radiosurgery and novel systemic therapies as well as the ongoing questions that remain under investigation.

Lung Cancer Surgery after Treatment with Anti-PD1/PD-L1 Immunotherapy for Non-Small-Cell Lung Cancer: A Case-Cohort Study

Simple Summary

The scope of indications for immune checkpoint inhibitors (ICIs) in non-small-cell lung cancer is growing, and an increasing number of patients are undergoing lung resection surgery after ICI treatment, with some technical difficulties being reported. The aim of our study was to determine if preoperative ICIs were associated with more difficult lung surgeries or poorer perioperative outcomes compared to surgeries performed after induction chemotherapy. We confirmed that ICIs were associated with tissue fibrosis and inflammation, particularly in centrally located lung tumours, although this did not translate to higher rates of perioperative morbidity. There was no 90-day mortality. We also found higher rates of major pathological response to pre-operative treatment in the ICI cohort and higher disease-free survival. Our findings further support the safety of lung resection in patients following preoperative ICIs.

Abstract

Background: Immune checkpoint inhibitors (ICIs) are the standard of care for non-resectable non-small-cell lung cancer and are under investigation for resectable disease. Some authors have reported difficulties during lung surgery following ICI treatment. This retrospective study investigated the perioperative outcomes of lung resection in patients with preoperative ICI. Methods: Patients with major lung resection after receiving ICIs were included as cases and were compared to patients who received preoperative chemotherapy without ICI. Surgical, clinical, and imaging data were collected. Results: A total of 25 patients were included in the ICI group, and 34 were included in the control group. The ICI patients received five (2–18) infusions of ICI (80% with pembrolizumab). Indications for surgery varied widely across groups (p < 0.01). Major pathological response was achieved in 44% of ICI patients and 23.5% of the control group (p = 0.049). Surgery reports showed a higher rate of tissue fibrosis/inflammation in the ICI group (p < 0.01), mostly in centrally located tumours (7/13, 53.8% vs. 3/11, 27.3% of distal tumours, p = 0.24), with no difference in operating time (p = 0.81) nor more conversions (p = 0.46) or perioperative complications (p = 0.94). There was no 90-day mortality. Disease-free survival was higher in the ICI group (HR = 0.30 (0.13–0.71), p = 0.02). Conclusions: This study further supports the safety and feasibility of lung resection in patients following preoperative treatment with ICI.

Classifying Oligometastatic Non-Small Cell Lung Cancer

An oligometastatic cancer state was first postulated in the 1990s by Hellman and Weichselbaum and described limited metastatic spread to a single or few sites of disease. It was hypothesized that this metastatic entity falls along a continuum of the natural history of cancer progression from a localized primary tumor to widespread metastases. Support for oligometastatic non-small cell lung cancer (NSCLC) has since been provided by multiple retrospective studies and then prospective randomized trials demonstrating better survival in this patient population after aggressive consolidative treatment. However, the lack of a universal definition of oligometastatic NSCLC has hindered a comparison between different studies and prevented well-defined recommendations for local consolidative treatment in this patient population. Attempts have been made to establish a common definition for use in clinical management and for the identification of inclusion criteria for future trials. In this review, we seek to summarize the current definitions of oligometastatic NSCLC based on recent expert consensus statements, previous randomized trials, and current treatment guidelines and to highlight the continued variability in current practice.

Predicted outcomes of subdividing M1-stage metastatic lung cancer based on the prognosis and the response to local consolidative therapy

Background

For stage IV non-small cell lung cancer (NSCLC) patients, systemic therapy is the main strategy, and local consolidative therapy tends to be performed for patients with oligometastases. The porpose of this article is to evaluate the prognostic effects of local consolidative therapy for patients with stage IV NSCLC and divide these patients into different subcategories to stratify the prognoses.

Methods

A total of 30,583 patients with stage IV NSCLC were identified in the Surveillance, Epidemiology, and End Results (SEER) database. To identify factors related to high cancer-specific mortality (CSM) rates and compare the prognostic effects of different treatment strategies, a competing risk model was developed. Furthermore, independent prognostic factors identified through multivariable analysis were employed to supplement the current M1 subcategory. Cumulative incidence curves were estimated using the Kaplan-Meier method, and the log-rank test was used to compare prognostic differences.

Results

The CSM rates of M1a, M1b, and M1c patients were significantly different [M1b versus M1a: subdistribution hazard ratio (SHR), 1.38; 95% confidence interval (CI), 1.31-1.45; P<0.001; M1c vs. M1a: SHR, 1.76; 95% CI, 1.67-1.85; P<0.001]. Patients were divided into five groups depending on the M1 subcategory and liver involvement (Group A, M1c NSCLC with liver involvement; Group B, M1c NSCLC without liver involvement; Group C, M1b NSCLC with liver involvement; Group D, M1b NSCLC without liver involvement; and Group E, M1a NSCLC). Univariable analysis showed that liver involvement was associated with increased cancer-specific mortality (CSM) rates in both M1b and M1c patients (A vs. B: SHR, 1.36; 95% CI, 1.30-1.43; P<0.001; C vs. D: SHR, 1.27; 95% CI, 1.20-1.35; P<0.001). Primary tumor surgery plus chemotherapy may substantially benefit patients, especially M1b patients (surgery alone: SHR, 0.425; 95% CI, 0.361-0.500; P<0.001 vs. chemotherapy alone: SHR, 0.366; 95% CI, 0.352-0.382; P<0.001 vs. chemotherapy plus surgery: SHR, 0.194; 95% CI, 0.165-0.228; P<0.001; no treatment used as reference).

Conclusions

Subdivision of M1 disease and awareness of liver involvement may help to inform the prognosis of stage IV NSCLC patients and facilitate treatment planning.

Knowing When to Use Stereotactic Ablative Radiation Therapy in Oligometastatic Cancer

Oligometastatic patients are a heterogeneous and yet not well-defined population. The actual definition identifies as oligometastatic, patients with 1-5 metastases in 1-3 different organs. However, only a proportion of these patients are "true" oligometastatic and therefore derive some kinds of benefit from local ablative approaches like stereotactic ablative radiation therapy (SABR). Since SABR is an easily accessible, effective and well-tolerated treatment, it is widely employed in the oligometastatic scenarios, without a particular focus on selection criteria. However, it should be crucial to identify predictive and prognostic features that could be clinically implemented. Therefore, we conducted this narrative review of the available literature to summarize all clinical, radiomic, genetic and epigenetic features found to be predictive of overall survival, progression-free survival or local control of oligometastatic patients treated with SABR.

Radiotherapy for oligometastatic non-small cell lung cancer: a narrative review

Preclinical and early clinical evidence suggest that radical radiotherapy of oligometastatic disease in non-small cell lung cancer (NSCLC) patients can impact outcomes with relatively limited toxicity. Whilst data from phase 2 randomized trials suggesting an improved overall survival (OS) with this treatment is promising, it has also illustrated the heterogeneity in this patient population and treatment. Oligometastatic disease in itself comprises a broad spectrum of patients, in terms of tumor load and location, stage of the disease and treatment history. This real-life variety in patient characteristics is often reflected in studies to a certain extent, hinting to the fact that all might benefit from radical radiotherapy to limited metastatic disease, yet leaving the question unanswered as to whom the ideal candidate is. Furthermore, differences between and within studies with regards to treatment modality, timing, radiation technique, and radiation dose are substantial. Also, preclinical and early clinical trials suggest that radiotherapy can work synergistically with checkpoint inhibitors by acting as an in situ cancer vaccine, therefore the combination of these two treatments in oligometastatic patients might entail the largest benefit. Ongoing randomized controlled phase 3 trials and prospective registry trials will further elucidate the true extent of benefit of this local treatment strategy and aid in identifying the ideal patient population and therapy. The current narrative review summarizes the clinical evidence on radiotherapy for oligometastatic NSCLC and highlights the remaining unknowns.

Defining oligometastatic non-small cell lung cancer: concept versus biology, a literature review

Objective

In this review, the concept of (synchronous) oligometastatic disease in patients with non-oncogene-driven non-small cell lung cancer (NSCLC) will be placed in the context of tumor biology and metastatic growth patterns. We will also provide considerations for clinical practice and future perspectives, which will ultimately lead to better patient selection and oligometastatic disease outcome.

Background

The treatment landscape of metastasized NSCLC has moved from "one-size fits all" to a personalized approach. Prognosis has traditionally been poor but new treatment options, such as immunotherapy and targeted therapy, brighten future perspectives. Another emerging development is the recognition of patients with so-called "oligometastatic" state of disease. Oligometastatic disease has been recognized as a distinct clinical presentation in which the tumor is stated to be early in its evolution of metastatic potential. It is suggested that this stage of disease has an indolent course, comes with a better prognosis and therefore could be considered for radical multimodality treatment.

Methods

Narrative overview of the literature synthesizing the findings of literature retrieved from searches of computerized databases, hand searches, and authoritative texts.

Conclusions

Oligometastatic NSCLC is a broad spectrum disease, with a variable prognosis. Although the biology and behavior of "intermediate state" of metastatic disease are not fully understood, there is evidence that a subgroup of patients can benefit from local radical treatment when integrated into a multimodality regime. The consensus definition of oligometastatic NSCLC, including accurate staging, may help to uniform future trials. The preferable treatment strategy seems to sequential systemic treatment with subsequent local radical treatment in patients with a partial response or stable disease. Prognostic factors such as N-stage, number and site of distant metastases, tumor volume, performance status, age, and tumor type should be considered. The local radical treatment strategy has to be discussed in a multidisciplinary team meeting, taking into account patient characteristics and invasiveness of the procedure. However, many aspects remain to be explored and learned about the cancer biology and characteristics of intermediate state tumors.

Epidemiology of oligometastatic non-small cell lung cancer: results from a systematic review and pooled analysis

Background

To describe the incidence and the clinical characteristics of oligometastatic non-small cell lung cancer (NSCLC) patients. Oligometastatic NSCLC is gaining recognition as a clinical condition with a different prognosis compared to multi metastatic disease. Usually, four different scenarios of oligometastatic disease can be described but not epidemiological data are available. To date, it is difficult to delineate an exhaustive epidemiological scenario because no uniform or shared definition of oligometastatic status exists, even though a recent consensus defined synchronous oligometastatic disease as having a maximum of 5 metastases in 3 different organs.

Methods

A systematic review and a pooled analysis of literature were performed. Article selection was based on the following characteristics: focus on lung cancers; dealing with oligometastatic settings and providing a definition of oligometastatic disease; number of metastatic lesions with or without the number of organs involved; providing some incidence or clinical characteristics of oligometastatic NSCLC patients. Series focusing on a specific single metastatic organ were excluded. The research was launched in MEDLINE (OvidSP) in March 2020. Full articles were individually and collectively read by the authors according to the previous criteria. Each author inspected the reference list included in the eligible articles. If the selection criteria were recognized, the article was reviewed by all authors and then included. Data on patient clinical features were pooled together from 31 articles selected.

Results

A total number of 31 articles have been selected for the analysis. The following variables were extracted from the publications: (I) number of metastases, (II) number of organs involved, (III) number of patients, (IV) number and percentage of males and females, (V) number and percentage of squamous and non-squamous histology, (VI) T and N status and/or stage of primary disease for oligometastatic setting. The data collected have been analyzed according to the oligometastatic setting.

Conclusions

Oligometastatic status is globally identified as a different clinical condition from multi metastatic NSCLC, although the clinical characteristics were consistent in the general metastatic population, even with a lower-than-expected TN status. The brain and bones were the most frequent organs involved. Lacking consensus definition, these results must be interpreted cautiously and a prospective evaluation is urgently needed.

Local ablative therapies in oligometastatic NSCLC-upfront or outback?-a narrative review

Patients with oligometastatic (OM) non-small cell lung cancer (NSCLC) have favorable outcomes compared to patients presenting with diffuse metastatic disease. Recent randomized trials have demonstrated safety and efficacy signals for local ablative therapies with radiotherapy, surgery, or radiofrequency ablation for OM-NSCLC patients alongside systemic therapies. However, it remains unclear whether local ablative therapy (LAT) should be offered either upfront preceding systemic therapies or following initial systemic therapies as local consolidative therapy (LCT). Establishing optimal timing of RT and systemic therapy combinations is essential to maximize efficacy while maintaining safety. Most published randomized trial evidence surrounding the benefits of LAT and systemic therapies were generated from OM-NSCLC patients receiving cytotoxic chemotherapy agents. With increasing use of novel agents such as targeted therapies (i.e., tyrosine kinase inhibitors) and immune checkpoint inhibitors in management of metastatic NSCLC patients, LAT timing may need to be modulated based on the use of specific agents. This narrative review will discuss the current evidence on either upfront LAT or LCT for OM-NSCLC based on published trials and cohort studies. We briefly explored the possible biological mechanisms of the potential clinical advantages of either approach. This review also summarized the ongoing trials incorporating both upfront LAT and LCT, and considerations for future LAT strategies.

Clinical prognostic factors in surgically treated oligometastatic non-small cell lung cancer: a systematic review

Background

Since the concept of oligometastatic (OM) disease was introduced in the oncological scenario of non-small cell lung cancer (NSCLC), these patients progressively became a new category of stage IV NSCLC in whom the multimodality approach, including surgery, may improve prognosis. This systematic review aimed to investigate the clinical prognostic factors in OM-NSCLC surgically treated with radical intent.

Methods

This systematic review is reported following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Cochrane’s Collaboration Tool was used to determine the risk of bias for the included studies’ primary outcome. A search strategy using a combination of free-text words, relevant MeSH headings and appropriate restrictions (time limit: from January 1997 to March 2020, language: English) was designed. Potentially qualified papers were subjected to an in-depth full-text examination after preliminary title/abstract screening to identify studies for inclusion in the systematic review. Data extracted included: study characteristics, baseline patient characteristics, primary and secondary outcomes. The Cochrane’s Collaboration Tool was used to determine the risk of bias for included studies’ primary outcome. The risk of bias due to incomplete outcome data was evaluated at an outcome level. However, at the study stage, the possibility of bias due to sequence generation, allocation concealment, blinding, selective reporting, or funding was assessed. Two independent observers calculated the probability of bias, and differences were resolved through dialogue and consensus.

Results

Nine studies were selected. Overall survival (OS) was 51.8 months and varied from 21.1 to 60 months, but results were not statistically significant. Positive prognostic factors for survival were cessation of smoking, age <60, a histologic grade of G1/G2, pN0. The presence of extra-brain OM and multiple metastases negatively affected survival.

Discussion

For otherwise stable patients with a single organ site with synchronous (or metachronous) extrathoracic M1 disease and no intrathoracic lymph node involvement, aggressive treatment should be used in the absence of randomized evidence to help determine the effective management of OM-NSCLC.

The Role of Surgery in Lung Cancer Treatment: Present Indications and Future Perspectives-State of the Art

Non-small cell lung cancers (NSCLC) are different today, due to the increased use of screening programs and of innovative systemic therapies, leading to the diagnosis of earlier and pre-invasive tumors, and of more advanced and controlled metastatic tumors. Surgery for NSCLC remains the cornerstone treatment when it can be performed. The role of surgery and surgeons has also evolved because surgeons not only perform the initial curative lung cancer resection but they also accompany and follow-up patients from pre-operative rehabilitation, to treatment for recurrences. Surgery is personalized, according to cancer characteristics, including cancer extensions, from pre-invasive and local tumors to locally advanced, metastatic disease, or residual disease after medical treatment, anticipating recurrences, and patients' characteristics. Surgical management is constantly evolving to offer the best oncologic resection adapted to each NSCLC stage. Today, NSCLC can be considered as a chronic disease and surgery is a valuable tool for the diagnosis and treatment of recurrences, and in palliative conditions to relieve dyspnea and improve patients' comfort.

How to optimize the incorporation of immunotherapy in trials for oligometastatic non-small cell lung cancer: a narrative review

Patients with oligometastatic disease (OMD) non-small cell lung cancer (NSCLC) are considered as a subgroup of metastatic NSCLC that can obtain long-term survival or even cure. Oligometastatic refers to a state of a limited number of metastases in a limited number of organs. In clinical guidelines it is stated that patients with oligometastatic NSCLC can benefit from the addition of local radical therapy (LRT) to systemic therapy. With the introduction of minimally invasive surgery, advances in interventional radiology and stereotactic radiotherapy (SRT), LRT is becoming feasible for more and more patients. Furthermore, the introduction of immune checkpoint inhibitors (ICI) in the treatment landscape of advanced NSCLC has improved the survival of these patients. Importantly, the use of ICI in combination with LRT is also of interest in the subgroup of NSCLC patients with OMD. For example, it has been suggested that SRT may synergize with ICI as several preclinical studies reported an increased tumor antigen release, improved antigen presentation, and T-cell infiltration in irradiated tumors. In this narrative review, we describe the current evidence of immunotherapy treatment in OMD NSCLC, with a focus on future trial design and problems that need to be addressed.

Prognostic factors of oligometastatic non-small-cell lung cancer following radical therapy: a multicentre analysis

OBJECTIVES

Patients with oligometastatic non-small-cell lung cancer (NSCLC) may benefit from therapy with curative intent. Our goal was to identify prognostic factors related to better prognosis in a multicentre analysis of patients who underwent surgery of primary tumours in combination with radical treatment of all metastatic sites.

METHODS

We retrospectively reviewed the records of oligometastatic patients who underwent resection of primary tumours at 4 centres (August 2001-February 2018). Oligometastasis was defined as ≤5 synchronous metastases in ≤2 organs. Radical metastatic treatment was surgery, radiotherapy or a combination. The Cox proportional hazards model was used for identification of prognostic factors on overall survival.

RESULTS

We treated 124 patients; 72 (58%) were men, mean age 60 ± 9.8 years, with 87 (70%) adenocarcinoma. Sixty-seven (54%) patients had positive pathologic-N stage (pN). Brain metastases were most common (n = 76; 61%) followed by adrenal (n = 13; 10%) and bone (n = 12; 10%). Systemic therapy was administered in 101 (82%) patients. Median follow-up was 60 months [95% confidence interval (CI) 41-86]. Thirty- and 90-day mortality rates were 0 and 2.4%, respectively. One-, 2-, and 5-year overall survival were 80%, 58% and 36%, respectively. Cox regression analysis showed that patients ≤60 years [hazard ratio (HR) 0.41, 95% CI 0.24, 0.69; P = 0.001] and patients with pN0 (HR 0.38, 95% CI 0.21-0.69; P = 0.002) had a significant survival benefit. The presence of bone metastases negatively affected survival (HR 2.53, 95% CI 1.05-6.09; P = 0.04).

CONCLUSIONS

Treatment with curative intent of selected oligometastatic NSCLC, including resection of the primary tumour, can be performed safely and with excellent 5-year survival rates, especially in younger patients with pN0 disease.

Lung cancer surgery in oligometastatic patients: outcome and survival

OBJECTIVES

A few studies have already demonstrated survival benefits for local treatment in solitary metastatic non-small-cell lung cancer (NSCLC). The aim of this study is to retrospectively investigate the role of surgery in patients with oligometastatic (OM) NSCLC.

METHODS

Between January 1998 and December 2018, 57 patients with OM stage IV NSCLC (1 or 2) underwent a multidisciplinary approach including lung cancer surgery, local treatment of the distant metastasis (DM) and systemic medical treatments.

RESULTS

All patients had DM synchronous to lung cancer. Fifty-one (90%) patients had a single DM whereas 6 (11%) patients had 2 DMs. Forty-eight (84%) patients underwent induction chemotherapy. We performed 47 (82%) lobectomies, 4 (7%) segmentectomies and 6 (11%) pneumonectomies. Pathological lymph node involvement was evident in 28 (49%) patients. Adjuvant chemotherapy was administered in 20 (35%) patients. Forty-six (81%) patients had local treatment of the DM before lung resection, and 11 (19%) patients had after lung resection; 6 (11%) patients had both treatments. The median overall survival (OS) was 30 months, with the 2-, 3- and 5-year OS of 57%, 50% and 30%, respectively. OS was significantly related to lymph node involvement (P = 0.04), size of the primary tumour (P < 0.001), neoadjuvant chemotherapy (P = 0.02) and the time period between metastasis diagnosis and primary tumour removal (P = 0.04).

CONCLUSIONS

Multidisciplinary approach is the gold standard in OM patients. Patients with no lymph node involvement are the best candidates, with an acceptable OS. Thus, patients with OM-NSCLC should not be excluded from surgery as a matter of principle.

Sequence For Surgical Resection of Primary Lung Tumor For Oligometastatic Non-Small Cell Lung Cancer

BACKGROUND

Differing surgical series for the treatment of primary lung tumor with synchronous oligometastatic stage IV non-small cell lung cancer (NSCLC) have been published; however, outcomes remain ambiguous.

METHODS

Patients with synchronous oligometastatic stage IV NSCLC treated from 2005 to 2017 were enrolled to identify the impact of treatment sequence (primary lung resection versus systemic treatment) on progression-free survival (PFS) and overall survival (OS).

RESULTS

Fifty-one patients received tumor resection (84% adenocarcinoma, 55% non-smokers, and 65% driver gene mutation). Resection occurred before or after systemic treatment in 33 (64.7%) and 18 (35.3%) patients, respectively. Patients who received resection first were older (62.1 vs. 54 year) and at a less advanced intrathoracic stage (18% vs. 44%). No significant differences were noted regarding perioperative complication (30% vs. 28%), length of hospital stay (9.0 vs. 10.5 days), percentage of disease progression (91% vs. 94%), overall death (70% vs. 78%), median PFS (14.0 vs. 22.8 months) and OS (44.6 vs. 53.2 months). Patients with single-organ metastasis had significantly longer PFS and OS than those with oligometastases (17.5 vs. 12.8 months, p=0.040 and 55.6 vs. 39.8 months, p=0.035), respectively. Multivariable Cox analysis identified non-solitary metastasis as the only independent predictor of PFS (hazard ratio 2.27; 95% CI, 1.07-4.81, p=0.033).

CONCLUSIONS

Primary lung resection before or after induction systemic therapy may benefit patients with oligometastatic NSCLC. Future randomized clinical trials examining the effect of treatment sequence is recommended.

Management of Synchronous Extrathoracic Oligometastatic Non-Small Cell Lung Cancer

Stage IV non-small cell lung cancer (NSCLC) accounts for 35 to 40% of newly diagnosed cases of NSCLC. The oligometastatic state-≤5 extrathoracic metastatic lesions in ≤3 organs-is present in ~25% of patients with stage IV disease and is associated with markedly improved outcomes. We retrospectively identified patients with extrathoracic oligometastatic NSCLC who underwent primary tumor resection at our institution from 2000 to 2018. Event-free survival (EFS) and overall survival (OS) were estimated using the Kaplan-Meier method. Factors associated with EFS and OS were determined using Cox regression. In total, 111 patients with oligometastatic NSCLC underwent primary tumor resection; 87 (78%) had a single metastatic lesion. Local consolidative therapy for metastases was performed in 93 patients (84%). Seventy-seven patients experienced recurrence or progression. The five-year EFS was 19% (95% confidence interval (CI), 12-29%), and the five-year OS was 36% (95% CI, 27-50%). Factors independently associated with EFS were primary tumor size (hazard ratio (HR), 1.15 (95% CI, 1.03-1.29); p = 0.014) and lymphovascular invasion (HR, 1.73 (95% CI, 1.06-2.84); p = 0.029). Factors independently associated with OS were neoadjuvant therapy (HR, 0.43 (95% CI, 0.24-0.77); p = 0.004), primary tumor size (HR, 1.18 (95% CI, 1.02-1.35); p = 0.023), pathologic nodal disease (HR, 1.83 (95% CI, 1.05-3.20); p = 0.033), and visceral-pleural invasion (HR, 1.93 (95% CI, 1.10-3.40); p = 0.022). Primary tumor resection represents an important treatment option in the multimodal management of extrathoracic oligometastatic NSCLC. Encouraging long-term survival can be achieved in carefully selected patients, including those who received neoadjuvant therapy and those with limited intrathoracic disease.

In Spite of Curative Radical Pulmonary Procedures, Lesser Pulmonary Resection Shows More Favorable Prognosis in Surgically Treated NSCLC With Synchronous Isolated Cranial Oligometastases

Oligometastatic disease in lung cancer is not a rare condition as previously thought. Among 812 non-small cell lung cancer patients treated surgically with lung resection between October 2011 and October 2018 at the Department of Thoracic Surgery, Florence Nightingale Hospitals, Turkey, 28 patients (3.4%) had synchronous cranial metastases. We analyzed synchronous isolated cranial metastases patients treated by locally ablative treatments (surgery, radiotherapy, or both). Metastases existing at the diagnosis of primary cancer were considered as synchronous, and their treatment was performed before (at least 1 month) or after (for maximum 1 month) surgery of the primary lung lesion. Prognostic factors affecting survival are evaluated retrospectively to identify clinical factors predicting survival in an effort to better select patients for surgery. Patients having T1-T2 primary lung tumors, no mediastinal lymph node metastasis, receiving minor anatomical lung resection, receiving neoadjuvant chemotherapy, having single cranial metastasis, and receiving surgical cranial metastasectomy were found to have better survival. According to tumor histology, having adenocarcinoma, and not having lymphovascular or visceral pleura invasion correlated with better survival. Average survival time was 52.1 months and median survival was 32 months. The last mortality during the follow-up was at 24 months; cumulative survival was 48.3% at that time. Our study was designed to define the criteria for patients with oligometastatic disease who may benefit from lung resection.

Protocol for a phase II randomised controlled trial of TKI alone versus TKI and local consolidative radiation therapy in patients with oncogene driver-mutated oligometastatic non-small cell lung cancer

INTRODUCTION

Tyrosine kinase inhibitors (TKIs) have significantly improved the progression-free survival (PFS) of metastatic non-small cell lung cancer (NSCLC) with oncogene mutations of epidermal growth factor receptor (EGFR) and anaplastic lymphoma kinase (ALK) compared with systemic therapy alone. However, the majority eventually develop resistance with a median PFS of 8-12 months. The pattern of failure studies showed disease relapse at the original sites of the disease-harbouring resistant tumour cells.

METHODS AND ANALYSIS

This study is designed as a phase II randomised controlled trial to evaluate the efficacy of local consolidative radiation therapy (LCRT) in addition to TKI in upfront oligometastatic NSCLC. Patients will be screened at presentation for oligometastases (≤5 sites) and will start on TKI after confirmation of EGFR or ALK mutation status. After initial TKI for 2-4 months, eligible patients will be randomised in a 1:1 ratio with stratification of oligometastatic sites (1-3 vs 4-5), performance status of 0-1 versus 2 and brain metastases. The standard arm will continue to receive TKI, and the intervention arm will receive TKI plus LCRT. Stereotactic body radiation therapy will be delivered to all the oligometastatic sites.The primary end point is PFS, and secondary end points are overall survival, local control of oligometastatic sites, toxicity and patient-reported outcomes. The sample size calculation took a median PFS of 10 months in the standard arm. To detect an absolute improvement of 7 months in the interventional arm, with a one-sided alpha of 5% and 80% power, a total of 106 patients will be accrued over a period of 48 months.

ETHICS AND DISSEMINATION

The study is approved by the Institutional Ethics Committee II of Tata Memorial Centre, Mumbai, and registered with Clinical Trials Registry-India, CTRI/2019/11/021872, dated 5 November 2019. All eligible participants will be provided with a participant information sheet and will be required to provide written informed consent for participation in the study. The study results will be presented at a national/international conference and will be published in a peer-reviewed journal.

How to handle oligometastatic disease in nonsmall cell lung cancer

Patients with nonsmall cell lung cancer and limited metastatic disease have been defined as oligometastatic if local ablative therapy of all lesions is amenable. Evidence from different clinical retrospective series suggests that this subgroup harbours better prognosis than other stage IV patients. However, most reports have included patients with inconsistent numbers of metastases in different locations treated by a variety of invasive and noninvasive therapies. As long as further results from randomised clinical trials are awaited, treatment decision follows an interdisciplinary debate in each individual case. Surgery and radiotherapy should capture a dominant role in the treatment course offering the option of a curative-intended local therapy in combination with a systemic therapy based on an interdisciplinary decision. This review summarises the current treatment standard in oligometastatic lung cancer with focus on an ablative therapy for both lung primary and distant metastases in prognostically favourable locations.

Clinical significance of bifocal treatment for synchronous brain metastasis in T1-2 non-small-cell lung cancers: JNETS0301

OBJECTIVES

The treatment of patients with brain metastases associated with non-small-cell lung cancer (NSCLC) is frequently challenging. Starting in 2003, we conducted a phase II study of surgery for patients with clinical T1-2N0-1 NSCLC with oligometastasis. The aim of this subset study was to assess the clinical significance of bifocal treatment for synchronous brain metastases in T1-2N0-1 NSCLC using prospectively collected data.

METHODS

In this phase II study of clinical T1-2N0-1 NSCLC patients with oligometastasis, 47 patients were enrolled from December 2003 to December 2016. Among them, 18 NSCLC patients with synchronous brain metastases were investigated in this subset analysis.

RESULTS

Fourteen patients underwent complete resection, and 4 underwent incomplete resection of the primary lung cancer. The number of synchronous brain metastases was one in 14 and multiple in 4 patients. After surgery for the primary lung cancer, 12 of 18 patients underwent treatment for their brain lesions, including stereotactic radiosurgery (SRS) in 10, surgical resection in 1, and SRS followed by surgical resection in 1. In 5 of the 18 patients (28%), the brain lesion was diagnosed as benign on follow-up radiological imaging. The 5-year overall survival rate after enrollment was 31.8% for all 18 patients and 35.2% for the 13 patients with brain metastases. Univariate analysis showed that having multiple brain lesions was a significant factor related to a worse prognosis.

CONCLUSION

For patients with suspected brain metastases associated with NSCLC, bifocal local treatment could be an acceptable therapeutic strategy, especially for solitary brain metastasis.

Proposing synchronous oligometastatic non-small-cell lung cancer based on progression after first-line systemic therapy

Despite the importance of accurate disease definitions for effective management and treatment decisions, there is currently no consensus on what constitutes oligometastatic non–small‐cell lung cancer (NSCLC). Predominant patterns of initial progressive disease (PD) after first‐line systemic therapy have been shown to be a substantial basis for local ablative therapy (LAT) for all disease sites in patients with oligometastatic NSCLC, suggesting that these patterns could be helpful in defining synchronous oligometastatic NSCLC. Therefore, this retrospective study aimed to propose a threshold number of metastases for synchronous oligometastatic NSCLC, based on the pattern of initial PD after first‐line systemic therapy. The cut‐off threshold number of metastases compatible with synchronous oligometastatic NSCLC was determined using receiver operating characteristic (ROC) curve analyses of PD at the initially involved sites alone. ROC analysis of 175 patients revealed that the presence of 1‐3 metastases before first‐line treatment (sensitivity, 85.9%; specificity, 97.3%; area under the curve, 0.91) was compatible with oligometastatic NSCLC, therefore we divided patients into oligometastatic NSCLC and non‐oligometastatic NSCLC groups. Multivariate logistic regression analyses revealed oligometastatic NSCLC to be the only independent predictor of PD at initially involved sites alone (odds ratio 165.7; P < .001). The median survival times in patients with oligometastatic or non‐oligometastatic NSCLC were 23.0 and 10.9 mo (hazard ratio, 0.51; P = .002), respectively. Based on these findings, we propose synchronous oligometastatic NSCLC as 1‐3 metastases in accordance with patterns of initial progression. The result of our study might be contributory to provide a common definition of synchronous oligometastatic NSCLC.

Management of Non-Small-Cell Lung Cancer Patients Initially Diagnosed With 1 to 3 Synchronous Brain-Only Metastases: A Retrospective Study

BACKGROUND

The treatment options for newly diagnosed non-small-cell lung cancer (NSCLC) patients with 1 to 3 synchronous brain metastases (BM) remain controversial. The current study aimed to comprehensively analyze the characteristics, local treatment paradigms, and survival outcomes in these populations.

PATIENTS AND METHODS

A total of 252 NSCLC patients initially diagnosed with 1 to 3 synchronous brain-only metastases were enrolled onto this study. Local therapy (LT) to primary lung tumors (PLT) and BM included surgery, radiotherapy, or both. Median overall survival (mOS) was measured among patients who received LT to both PLT and BM (all-LT group), patients who were treated with LT to either PLT or BM (part-LT group), and patients who did not receive any LT (non-LT group).

RESULTS

The mOS for all-LT (n = 70), part-LT (n = 113), and non-LT (n = 69) groups was 33.2, 18.5, and 16.8 months, respectively (P = .002). The OS rates at 5 years for the all-LT, part-LT, and non-LT groups were 25.5%, 16.2%, and 0, respectively. Multivariable analysis revealed that all-LT versus non-LT, pretreatment Karnofsky performance status > 70, histology of adenocarcinoma, thoracic stage I-II, EGFR mutation, ALK positive, and second-line systemic therapies were independent prognostic factors for improved mOS.

CONCLUSIONS

The current study showed that LT for both PLT and BM is associated with superior OS in appropriately selected NSCLC patients initially diagnosed with 1 to 3 synchronous BM. Prospective trials are urgently needed to confirm this finding.

Linear accelerator-based stereotactic body radiation therapy in the treatment of oligometastatic disease

The present study reports the clinical outcomes of hypofractionated stereotactic body radiation therapy (SBRT) for oligometastasis (OM) originating from various tumors. Between February 2012 and April 2017, 40 patients with unresectable OM were treated with SBRT. Of these patients, 92% showed a solitary nodal metastasis and the rest had up to three metastases. The dose prescription was 50 Gy in 10 fractions with three-dimensional conformal techniques or volumetric intensity-modulated arc therapy. Median follow-up was 14 months. Of the 40 patients, none showed local progression at the site of SBRT, but 20 patients showed tumor growth at distant sites during follow-up. The 2- and 3-year overall survival rates were 45.1 and 36.1%, respectively. The 2- and 3-year progression-free survival rates were 35.4 and 26.5%, respectively. The interval between diagnosis and detection of OM (<2 vs. >2 years) and primary tumor site (esophagus vs. others) emerged as significant variables affecting survival. Grade 3 subacute and grade 4 chronic toxicities were observed in 1 and 2 patients, respectively. SBRT of 50 Gy in 10 fractions for OM from various primary tumors was shown to lead to good clinical outcomes from the viewpoints of local control and toxicity frequency. However, additional studies are required to identify the patient groups likely to receive maximal benefits from such treatment.

Management of Oligometastatic Disease in Advanced Non-Small Cell Lung Cancer

Non-small cell lung cancer with very limited extent of metastatic spread commonly is termed, oligometastatic disease (OMD), and typically described as no more than 3 to 5 lesions. Definitive local therapy potentially leads to significant improvement in progression-free survival and overall survival. OMD may occur de novo prior to initiation of systemic therapy or as an induced state after initiation of systemic therapy. Although prospective data are limited to small trials, they have consistently supported local therapy as an appropriate consideration if not a clear standard of care for well-selected patients. Several trials in OMD are ongoing.

Treatment outcomes in oligometastatic non-small-cell lung cancer: A single-centre experience

BACKGROUND

Even in oligometastatic stage 4 disease, survival rates are higher when curative approaches focus on both the primary tumour and metastasis. So, we aim to analyse our results of oligometastatic disease retrospectively.

METHODS

In total, data on 52 non-small-cell lung cancer (NSCLC) patients with limited metastasis (one to three synchronous/metachronous) were retrospectively analysed. All treatment modalities associated with various treatment modalities [surgery, chemoradiotherapy (CRT), supportive care and palliative chemotherapy] were compared in terms of survival. Curative treatment consisted of surgery or CRT (concurrent or sequential).

RESULTS

The median overall survival (OS) time was 35.2 ± 4.1 months. Surgery was superior to CRT in terms of OS (36.7 months vs 27.4 months, P > 0.05). Progression-free survival was 29.4 ± 3.9 months, and survival after first progression (SAFP) was 15.6 ± 2.8 months. Patients in whom a metastasectomy was performed had significantly higher rate of SAFP as compared with those who did not have a metastasectomy (20.07 ± 3.8 months vs 7.9 ± 1.7 months P = 0.046). According to pathological type, an adenocarcinoma was associated with better SAFP than a non-adenocarcinoma (23 ± 4.1 vs 6.4 ± 1.5, P = 0.002). The 1- and 2-years OS rates were 67% and 50.4%, respectively. Among the curative treatment group, the OS of patients younger than 65 years (n = 25) was 31 months, whereas that of patients older than 65 years (n = 13) was 22 months (P = 0.88).

CONCLUSION

In well-selected NSCLC patients with limited metastasis, survival rates can reach up to 3 years, even in a geriatric population. Clinical N staging and co-morbidity are important prognostic factors.

Microwave ablation for non-small cell lung cancer with synchronous solitary extracranial metastasis

AIMS

Local therapy including surgery or radiotherapy has been reported for the treatment of non-small cell lung cancer (NSCLC) with synchronous solitary metastasis, while studies with other local ablative treatment are rare. Here, we summarized our single-center experience of microwave ablation (MWA) for both primary and metastatic lesions in NSCLC patients with synchronous solitary extracranial metastases.

PATIENTS AND METHODS

We retrospectively screened our institute database from January 2014 to Jun 2019. NSCLC patients with synchronous extracranial solitary metastasis with primary and metastatic lesions that were treated with MWA were identified and analyzed.

RESULTS

Of the 1472 stage IV NSCLC patients found, 38 were diagnosed with synchronous extracranial solitary metastasis and 29 of them received MWA for primary and metastatic lesions. The most common distant metastases were contralateral lung metastases (14 cases), followed by bone (6), liver (4), adrenal gland (3) and pleura metastases (1). Median OS and PFS was 21.5 and 12.5 months, respectively. Patients with N0 had significantly longer PFS (median 18.5 vs. 8.0 months) and OS (median 42.7 vs. 19.0 months). In addition, systemic therapy was showed to be a prognostic factor for better PFS (12.9 vs. 7.5 months). Clinical pathological factors including age, histology, T stage, PS score, and metastasis locations are not significantly associated with survival.

CONCLUSIONS

MWA may serve as an alternative treatment for NSCLCs with synchronous solitary extracranial metastases.

Results of surgical resection in lung cancer with synchronous brain metastasis

Background

This study aims to investigate the factors affecting the survival of operated non-small cell lung cancer patients with synchronous brain metastasis.

Methods

Clinical outcomes of a total of 16 patients (14 males, 2 females; mean age 60 years; range, 41 to 71 years) who were diagnosed with non-small cell lung cancer and concomitant solitary/oligo brain metastasis and who underwent an intervention primarily for cranium, followed by lung resection in our clinic between January 2012 and January 2016 were retrospectively analyzed. Cranial surgery or gamma-knife radiosurgery was performed in the treatment of brain metastases.

Results

Twelve patients with solitary brain metastasis underwent cranial surgery, while four patients with solitary/oligo metastases underwent gamma-knife radiosurgery prior to pulmonary resection. Definitive pathological examination revealed adenocarcinoma in 13 patients and squamous-cell lung carcinoma in three patients. Mean survival time was 15.3±8.6 months. One-year and two-year survival rates were 56.2% and 32%, respectively. The number of brain metastases, treatment type, tumor cell type, resection type, and status of lymph nodes were not statistically significantly associated with survival (p>0.05).

Conclusion

Cranial surgery or gamma-knife radiosurgery followed by aggressive lung resection can be effectively applied in selected non-small cell lung cancer patients with synchronous brain metastasis. However, the suitability of the primary tumor and brain metastases for complete resection is of utmost importance in patient selection.

Efficacy and safety of microwave ablation in the treatment of patients with oligometastatic non-small-cell lung cancer: a retrospective study

Purpose: Patients with oligometastatic non-small-cell lung cancer (NSCLC) benefit from local control treatments such as surgery or irradiation. The efficacy and safety of microwave ablation (MWA) in these patients was unknown. Material and methods: Between January 2011 and April 2018, eligible patients were retrospectively enrolled. MWA was conducted for both primary lesions and metastatic lesions in patients with synchronous metastases and in metastatic lesions for patients with metachronous metastases. The primary endpoint was progression-free survival (PFS), and the secondary endpoints were overall survival (OS), technical success, technique efficacy, and complications. Results: Seventy-nine patients with 103 oligometastatic lesions were enrolled. A total of 20 primary lesions and 96 metastatic lesions were treated with MWA during 101 procedures. Technical success was achieved in all patients. Technique efficacy was achieved in 72 patients (91.1%). The median PFS and OS were 14.0 and 47.8 months, respectively. Forty-four patients (55.7%) developed complications with 21 (29.6%) of these patients developing major complications. All complications were resolved via appropriate medical treatments, and no MWA-related deaths occurred. Conclusion: MWA was safe and effective for patients with oligometastatic NSCLC.

Radiosurgery and fractionated stereotactic radiotherapy in oligometastatic/oligoprogressive non-small cell lung cancer patients: Results of a multi-institutional series of 198 patients treated with "curative" intent

OBJECTIVES

stereotactic radiosurgery (SRS) and fractionated stereotactic radiotherapy (FSRT) are a therapeutic option for Oligometastatic/Oligoprogressive (OM/OP) NSCLC. This retrospective multicentre analysis aims to analyse clinical outcomes and treatment related toxicity of patients treated to all sites of know disease with SRS and/or FSRT for OM/OP NSCLC in 8 Italian radiation oncology centres.

MATERIALS AND METHODS

From January 2016 to January 2017 198 OM/OP NSCLC patients (pts) were treated in 8 Centres. Inclusion criteria were as follows: 1-5 lesions at onset or after previous systemic treatment; Pts must have all metastatic lesions treated. Endpoints analysed were local progression free survival (LPFS); out-of-field recurrence free survival (OFPS); progression free survival (PFS); overall survival (OS). Time to New systemic Therapy free survival (TNT) and toxicity were also analysed.

RESULTS

At the time of radiotherapy, 119 pts (60 %) were treated for a single lesion, 49 (25 %) for 2 lesions, 30 (15 %) for 3-5 metastases. Total number of lesions treated was 333: 204 brain, 68 lung, 24 bone, 16 nodal, 12 adrenal, 8 liver and 1 soft tissue. 83/198 pts (41.8 %) had the primary tumour controlled at the time of the SRT. After a median follow-up of 18 months, median OS and PFS were 29.6 months and 10.6 months, respectively. One year LPFS and OPFS were 90 % and 47 %, respectively. Median TNT was 10 months. At univariate analysis factors associated with better OS were PS 0-1; controlled primary tumour, 1-2 lesions; extracranial metastasis. Multivariate analysis confirmed number of lesions <3 and extracranial metastasis to be related with better survival (Relative Risk 0.4 and 0.41, respectively). Two cases of death possibly related to brain radionecrosis were observed.

CONCLUSION

OM/OP NSCLC pts treated with an ablative SRT to all metastatic sites have fair outcomes with acceptable toxicity. Better results might be achieved in case of low disease burden and extracranial possibly when primary tumour is controlled.

Stereotactic Body Radiation Therapy for Extracranial Oligometastatic Non-small-cell Lung Cancer: A Systematic Review

Stereotactic body radiation therapy (SBRT) has emerged as a treatment modality for selected patients with oligometastatic non-small-cell lung cancer (NSCLC). The objectives of this systematic review were to explore the benefits and risks of SBRT for extracranial oligometastatic NSCLC. The MEDLINE, Embase, PubMed, and CENTRAL databases were searched for relevant articles from January 1, 2000 to July 23, 2019. Fully published phase III or phase II trials of any sample size were included. Retrospective series published in manuscript form with at least 50 patients were also included. Four prospective phase II randomized trials (total, 188 participants), 4 prospective non-randomized studies (total, 140 participants), and eleven retrospective studies (total, 1288 participants) were included in this systematic review. A variety of dose fractionation schemes were used. The median overall survival (OS) ranged from 13.5 to 55 months. Progression-free survival (PFS) ranged from 4.4 to 14.7 months. Quality of life outcomes were reported in 2 studies. None of the studies reported symptom control outcomes. There are no fully completed phase III randomized trials that clarify the risks and benefits of SBRT for oligometastatic NSCLC. Higher PFS and OS with SBRT were reported in 4 phase II randomized studies. The results from mature phase III randomized data regarding whether SBRT for oligometastatic NSCLC benefits patients in terms of OS, PFS, quality of life, and symptom control are needed.