Metastasis directed stereotactic radiotherapy in NSCLC patients progressing under targeted- or immunotherapy: efficacy and safety reporting from the 'TOaSTT' database

Systematic review of the efficacy of stereotactic ablative radiotherapy for oligoprogressive disease in metastatic cancer

BACKGROUND

Stereotactic Ablative Radiotherapy (SABR) for the treatment of oligometastatic disease can improve survival and delay the requirement for systemic therapy. The benefits of SABR in oligoprogressive disease are less well-defined. Here, we evaluate the available evidence investigating the efficacy of SABR in the treatment of oligoprogressive disease.

METHODS

A systematic review was carried out following PRISMA guidelines. Medline and Embase databases were searched using the terms "stereotactic radiotherapy" OR "SABR" OR "Stereotactic Ablative Body Radiotherapy" OR "SBRT" OR "SRT" AND "oligoprogression" in May 2022, June 2023, and February 2024. Studies were excluded where: SABR was used as a radical treatment, a specific oligoprogressive cohort could not be identified, publication was as a conference abstract or where fewer than 10 patients were recruited. Studies treating only brain metastases were also excluded. The site of primary tumour, oligoprogressive sites, rates of overall survival (OS), progression free survival (PFS), local control (LC) and time to next systemic therapy were collected.

RESULTS

Thirty-three full text studies were included. These consisted of single centre and multi-institutional observational studies, case series and phase II trials. Twenty-two studies were related to a specific tumour type: 12 urological cancer (9 prostate, 3 renal cancer), 6 non-small cell lung cancer, 2 colorectal cancer, 2 breast cancer and 11 were studies covering multiple tumour sites (5 studies involving SABR to a single organ and 6 studies involving SABR to multi-organ). Median PFS was >6 months in patients with oligoprogressive prostate, non-small cell lung cancer and renal cancer patients.

CONCLUSIONS

SABR appears to have clinical benefit in oligoprogresssive prostate, lung, and renal patients. However, the optimal management of patients with oligoprogressive disease is still somewhat uncertain due to lack of prospective data. This will hopefully become clearer in the near future with the publication of further randomised trials.

The Emerging Role of Radiotherapy in Oligoprogressive Non-Small Cell Lung Cancer

Oligoprogressive disease (OPD) is an emerging concept that describes patients who have progression of disease in a limited number of metastatic sites while on systemic therapy. Growing evidence has suggested the integration of local ablative therapy with systemic agents in patients with OPD further improves survival. In oligoprogressive non-small cell lung cancer, stereotactic body radiotherapy may have an important role in the effective local control of selective progressing metastases, which may translate to better patient outcomes. This review explores the treatment paradigm of this subset of patients and provides an update on the current existing literature on this topic.

Metastases-directed stereotactic body radiotherapy in combination with targeted therapy or immunotherapy: systematic review and consensus recommendations by the EORTC-ESTRO OligoCare consortium

Stereotactic body radiotherapy (SBRT) for patients with metastatic cancer, especially when characterised by a low tumour burden (ie, oligometastatic disease), receiving targeted therapy or immunotherapy has become a frequently practised and guideline-supported treatment strategy. Despite the increasing use in routine clinical practice, there is little information on the safety of combining SBRT with modern targeted therapy or immunotherapy and a paucity of high-level evidence to guide clinical management. A systematic literature review was performed to identify the toxicity profiles of combined metastases-directed SBRT and targeted therapy or immunotherapy. These results served as the basis for an international Delphi consensus process among 28 interdisciplinary experts who are members of the European Society for Radiotherapy and Oncology (ESTRO) and European Organisation for Research and Treatment of Cancer (EORTC) OligoCare consortium. Consensus was sought about risk mitigation strategies of metastases-directed SBRT combined with targeted therapy or immunotherapy; a potential need for and length of interruption to targeted therapy or immunotherapy around SBRT delivery; and potential adaptations of radiation dose and fractionation. Results of this systematic review and consensus process compile the best available evidence for safe combination of metastases-directed SBRT and targeted therapy or immunotherapy for patients with metastatic or oligometastatic cancer and aim to guide today's clinical practice and the design of future clinical trials.

Stereotactic ablative radiotherapy for acquired resistance to EGFR therapy in metastatic non-small cell lung cancer

The advent of targeted therapy has transformed the treatment paradigm and survival of patients with metastatic non-small cell lung cancer (NSCLC) with driver mutations. The development of acquired resistances during treatment with tyrosine kinase inhibitors (TKIs) impedes a prolonged survival in many patients. This fact is leading to the use of locally ablative therapies such as stereotactic ablative radiotherapy (SABR) to counter these resistances. SABR is a non-invasive treatment that can be delivered in multiple locations and has already proven effective in oligometastatic disease. Clinical evidence suggests that the combination of SABR with TKIs prolongs progression-free survival (PFS) in metastatic NSCLC patients with mutations in epidermal growth factor receptor (EGFR), with international guidelines recommending their use in unfavorable scenarios such as oligoprogressive disease. In this publication, we have reviewed the available evidence on EGFR-TKIs resistance mechanisms and the combination of SABR with TKI in metastatic NSCLC with EGFR mutations. We also describe the utility and clinical recommendations of this combination in oligometastatic and oligoprogressive disease.

Immunotherapy in Advanced NSCLC Without Driver Mutations: Available Therapeutic Alternatives After Progression and Future Treatment Options

The treatment paradigm of non-small-cell lung cancer without oncogenic drivers has varied dramatically in recent years and is constantly evolving. Immune- checkpoint inhibitors have demonstrated unprecedented durable efficacy in a subset of these patients, so these drugs have become the standard of care in most cases. There are different ways to deliver these agents, such as monotherapy and combinations of immunotherapy or chemotherapy plus immunotherapy. Treatment selection is complicated by an absence of head-to-head comparisons in randomized trials because these agents have gained approval by demonstrating superiority to platinum-doublet chemotherapy alone. Unfortunately, most patients will progress and die from their disease despite advances. Furthermore, after progression on these agents, there is a lack of randomized controlled data to support further management, constituting an unmet need. This review discusses the therapeutic alternatives after progression, summarizes mechanisms of resistance and progression patterns, and describes the main approaches under clinical investigation in the field.

Outcomes With Local Therapy and Tyrosine Kinase Inhibition in Patients With ALK/ROS1/RET-Rearranged Lung Cancers

PURPOSE

Local therapy prolongs progression-free survival in patients with oligometastatic non-small-cell lung cancers treated with chemotherapy. We previously reported that local therapy also prolongs survival and time to next therapy in patients on tyrosine kinase inhibitors (TKIs) for EGFR-mutant lung adenocarcinomas. Here, we investigate the role of local therapy in patients progressing on TKIs for ALK/ROS1/RET-rearranged lung adenocarcinomas.

MATERIALS AND METHODS

Patients with advanced ALK/ROS/RET-rearranged lung adenocarcinomas who underwent radiation, surgery, or percutaneous thermal ablation from 2012 to 2020 for progression on an ALK/ROS1/RET TKI were included. Progression patterns were identified. Times from local therapy to progression, next therapy, and death were measured.

RESULTS

Sixty-one patients with ALK (n = 37), ROS1 (n = 12), and RET (n = 12) fusions were identified. Patients received radiotherapy (92%), surgery (13%), and percutaneous thermal ablation (8%). Local therapy was administered for solitary/oligoprogressive (94%) or polyprogressive (6%) disease. For most patients (85%), local therapy addressed all progressing sites. The median times from any local therapy to subsequent progression and next systemic therapy were 6.8 months (95% CI, 5.1 to 8.1) and 10 months (95% CI, 8.4 to 15.3), respectively. Third or greater local therapy was associated with shorter time to progression and next therapy than first/second local therapies (hazard ratio, 4.97; P < .001 and hazard ratio, 2.48; P < .001). The median overall survival from first local therapy was 34 months (95% CI, 26 to not reached).

CONCLUSION

Local therapy for progression on ALK, ROS1, or RET TKIs is associated with clinically meaningful time on continued TKI therapy beyond progression, especially earlier in the course of disease.

Radiotherapy improves the outcomes of immunotherapy with Sintilimab in non-small-cell lung cancer: A real-world analysis

Introduction

Radiotherapy may augment systemic antitumor responses to immunotherapy. We did a retrospective study to infer whether radiotherapy improves outcomes to immunotherapy in patients with stage III and IV non-small-cell lung cancer (NSCLC).

Methods

This retrospective study conducted at Enze Medical Center enrolled 259 patients with histopathology confirmed NSCLC from December 2018 to December 31, 2021. All were treated with Sintilimab, some patients received radiotherapy at an appropriate time point. Radiation type includes conventional radiotherapy and stereotactic body radiotherapy. The progression-free survival (PFS), and overall survival (OS) were the primary endpoint.

Results

A retrospective analysis was performed on 259 patients, of whom 140 had been treated with immunotherapy lonely and 119 had been remedied with immunotherapy plus radiotherapy. Baseline variables were well balanced between the two groups, including gender, age, smoking status, TNM staging, number of metastases, ECOG score, pathological type and lines of previous systemic therapy. The median PFS in the immunotherapy alone group was 5.00 months (95%CI 4.38-5.62) versus immunotherapy plus radiotherapy was 9.00 months (5.95-12.05; p<0.001). The median OS in the immunotherapy alone group was 16.00 months (12.59-19.42) versus immunotherapy plus radiotherapy was 30.00 months (20.75-39.25; p=0.027). PFS was finer in the radiotherapy plus immunotherapy group than the immunotherapy group alone in both stage III(P=0.0069) and Stage IV(P=0.006) patients. In the univariate analysis, radiotherapy, male, ECOG=0 and <2 lines of previous systemic therapy were connected with an observably better PFS (P<0.001; P=0.03; P=0.002;P=0.021). In a multivariate analysis, radiotherapy, ECOG=0 and <2 lines of previous systemic therapy were independent prognostic factors with a markedly better PFS (P<0.001; P=0.006;P=0.009). An univariate analysis, radiotherapy, male, stage III, non-metastasis, ECOG=0 and squamous carcinoma were associated with a significantly better OS (P=0.032, P=0.036,P=0.002,P<0.001,P=0.002,P=0.025). A multivariate analysis, non-metastasis was a standalone prognostic indicator with a significantly better OS (P=0.006). However, radiotherapy was a tendency indicator with a better OS (HR0.70 95% CI 0.47-1.06). There were also no obvious increases in adverse events in the combination group.

Conclusions

Radiotherapy with addition of immunotherapy was observably linked to a better outcome in patients with III and IV staging NSCLC.

A critical review on oligometastatic disease: a radiation oncologist's perspective

Since the first definition by Hellman and Weichselbaum in 1995, the concept of OligoMetastatic Disease (OMD) is a growing oncology field. It was hypothesized that OMD is a clinical temporal window between localized primary tumor and widespread metastases deserving of potentially curative treatment. In real-world clinical practice, OMD is a “spectrum of disease” that includes a highly heterogeneous population of patients with different prognosis. Metastasis directed therapy with local ablative treatment have proved to be a valid alternative to surgical approach. Stereotactic body radiation therapy demonstrated high local control rate and increased survival outcomes in this setting with a low rate of toxicity. However, there is a lack of consensus regarding many clinical, therapeutic, and prognostic aspects of this disease entity. In this review, we try to summarize the major critical features that could drive radiation oncologists toward a better selection of patients, treatments, and study endpoints. With the help of a set of practical questions, we aim to integrate the literature discussion.

18F FDG PET/CT and Novel Molecular Imaging for Directing Immunotherapy in Cancer

Immunotherapy has transformed the treatment landscape of many cancers, with durable responses in disease previously associated with a poor prognosis. Patient selection remains a challenge, with predictive biomarkers an urgent unmet clinical need. Current predictive biomarkers, including programmed death-ligand 1 (PD-L1) (measured with immunohistochemistry), are imperfect. Promising biomarkers, including tumor mutation burden and tumor infiltrating lymphocyte density, fail to consistently predict response and have yet to translate to routine clinical practice. Heterogeneity of immune response within and between lesions presents a further challenge where fluorine 18 fluorodeoxyglucose PET/CT has a potential role in assessing response, stratifying treatment, and detecting and monitoring immune-related toxicities. Novel radiopharmaceuticals also present a unique opportunity to define the immune tumor microenvironment to better predict which patients may respond to therapy, for example by means of in vivo whole-body PD-L1 and CD8+ T cell expression imaging. In addition, longitudinal molecular imaging may help further define dynamic changes, particularly in cases of immunotherapy resistance, helping to direct a more personalized therapeutic approach. This review highlights current and emerging applications of molecular imaging to stratify, predict, and monitor molecular dynamics and treatment response in areas of clinical need.

Better survival of patients with oligo- compared with polymetastatic cancers: a systematic review and meta-analysis of 173 studies

Background: The modern concept of oligometastatic (OM) state has been initially developed to describe patients with a low burden of disease and with a potential for cure with local ablative treatments. We systematically assessed the risk of death and relapse of oligometastatic (OM) cancers compared to cancers with more diffuse metastatic spread, through a meta-analysis of published data. 

Methods: PubMed, the Cochrane Library, and EMBASE were searched for studies reporting prognosis of patients with OM solid tumors. Risk of death and relapse were extracted and pooled to provide an adjusted hazard ratio with a 95% confidence interval (HR 95%CI).  The primary outcome of the study refers to overall mortality in OM vs. polymetastatic (PM) patients. 

Results. Mortality and relapse associated with OM state in patients with cancer were evaluated among 104,234 participants (n=173 studies). Progression-free survival was better in patients with OM disease (hazard ratio [HR] = 0.62, 95% CI 0.57–0.68; P <.001; n=69 studies). Also, OM cancers were associated with a better overall survival (OS) (HR = 0.65, 95% CI 0.62-0.68; P<.01; n=161 studies). In colorectal (CRC), breast, non-small cell lung cancer (NSCLC) and renal cell carcinoma (RCC) the reduction in the risk of death for OM patients were 35, 38, 30 and 42%, respectively. Biliary tract and cervical cancer do not significantly better in OM stage likely for paucity of data.

Conclusions. Patients with OM cancers have a significantly better prognosis than those with more widespread stage IV tumors. In OM cancer patients a personalized approach should be pursued.

Role of Radiosurgery and Stereotactic Ablative Radiotherapy for Oligometastatic Non-Oncogene Addicted NSCLC

Local ablative therapy (LAT), intended as stereotactic ablative radiotherapy or stereotactic radiosurgery, is a well-recognized effective treatment for selected patients with oligometastatic NSCLC. Current clinical evidence supports LAT alone or in combination with systemic therapies. Our retrospective mono-institutional study aims to assess the role of LAT with a peculiar focus on the largest series of non-oncogene addicted oligometastatic NSCLC patients to date. We included in this analysis all patients with the mentioned disease characteristics who underwent LAT for intracranial and/or extracranial metastases between 2011 and 2020. The main endpoints were local control (LC), progression free survival (PFS) and overall survival (OS) in the whole population and after stratification for prognostic factors. We identified a series of 245 consecutive patients (314 lesions), included in this analysis (median age 69 years). In 77% of patients, a single metastasis was treated with LAT and intracranial involvement was the most frequent indication (53% of patients) in our series. The overall response rate (ORR) after LAT was 95%. In case of disease progression, 66 patients underwent new local treatments with curative intent. With a median follow-up of 18 months, median PFS was 13 months (1-year PFS 50%) and median OS was 32 months (1-year OS 75%). The median LC was not reached (1-year LC 89%). The presence of brain metastases was the only factor that negatively affected all clinical endpoints, with a 1-year LC, PFS and OS of 82%, 29% and 62% respectively, compared to 95%, 73% and 91%, respectively, for patients without BMs (p < 0.001 for each endpoint). At the multivariate analysis, mediastinal nodal involvement at baseline (p = 0.049), ECOG PS = 1 (p = 0.011), intracranial disease involvement (p = 0.001), administration of chemotherapy in combination with LAT (p = 0.020), and no delivery of further local treatment for progression or delivery of focal treatment for intracranial progression (p < 0.001) were related to a poorer OS. In our retrospective series, which is to our knowledge the largest to date, LAT showed encouraging results and confirmed the safety and effectiveness of focal treatments in non-oncogene addicted oligometastatic NSCLC patients.

Management of oligoprogression in non-small cell lung cancer patients

Oligoprogression is an emerging concept in oncology representing a state where after an initially successfully local or systemic treatment a disease progression occurs characterized by the appearance of a single or few new lesions. We reviewed the literature and explained the rationale of the therapeutic choices by referring to the current guidelines and literature data. In any case, the treatment of oligometastatic disease should be tailored to suit the individual patient with the aim of maximizing the benefit of each line of therapy.

Management of Oligoprogression in Patients with Metastatic NSCLC Harboring ALK Rearrangements

Simple Summary

The growing efficacy and availability of new targeted systemic therapies have markedly improved the prognosis of metastatic lung cancer patients harboring ALK rearrangements. The use of effective targeted therapies capable of maintaining a prolonged control of disease, for as long as possible, is paramount to ensure the best survival outcomes. In this regard, in cases of oligoprogression, “beyond progression” systemic treatment added to local ablative therapies is considered a feasible option in an attempt to improve the quality and quantity of patients’ lives, even if based on retrospective data. Certainly, treatment of ALK rearranged lung cancer patients with oligoprogressive disease must be individualized and based on multidisciplinary decisions. Above all, when further molecular targeted therapies are available, options must always be evaluated, especially in case of cerebral progression. In this review, we provide an updated and comprehensive overview of the main treatment strategies in cases of ALK rearranged oligoprogression.

Abstract

Personalized treatment based on driver molecular alterations, such as ALK rearrangement, has revolutionized the therapeutic management of advanced oncogene-addicted NSCLC patients. Multiple effective ALK tyrosine kinase inhibitors (TKIs), with the amelioration of the activity at central nervous system level, are now available, leading to substantial prognosis improvement. The exposure to TKIs triggers resistance mechanisms and the sequential administration of other TKIs and chemotherapy is, for the most part, not targeted. In this context, extending the benefit deriving from precision medicine is paramount, above all, when disease progression occurs in a limited number of sites. Retrospective data indicate that, in oligoprogressive disease, targeted therapy beyond progression combined with definitive local treatment of the progressing site(s) is an effective alternative. In these cases, a multidisciplinary approach becomes essential for an integrated treatment strategy, depending on the site of disease progression, in order to improve not only survival, but also quality of life. In this review we provide an updated and comprehensive overview of the main treatment strategies in cases of ALK rearranged oligoprogression, including systemic treatment as well as local therapy, and report a real-world clinical story, with the final aim of identifying the most promising management for this subset of patients.

Stereotactic Radiotherapy for Oligoprogression in Metastatic Renal Cell Cancer Patients Receiving Tyrosine Kinase Inhibitor Therapy: A Phase 2 Prospective Multicenter Study

BACKGROUND

Despite the paucity of prospective evidence, stereotactic radiotherapy (SRT) is increasingly being considered in the setting of oligoprogression to delay the need to change systemic therapy.

OBJECTIVE

To determine the local control (LC), progression-free survival (PFS), cumulative incidence of changing systemic therapy, and overall survival (OS) after SRT to oligoprogressive metastatic renal cell carcinoma (mRCC) lesions in patients who are on tyrosine kinase inhibitor (TKI) therapy.

DESIGN, SETTING, AND PARTICIPANTS

A prospective multicenter study was performed to evaluate the use of SRT in oligoprogressive mRCC patients. Patients with mRCC who had previous stability or response after ≥3 mo of TKI therapy were eligible if they developed progression of five of fewer metastases. Thirty-seven patients with 57 oligoprogressive tumors were enrolled.

INTERVENTION

Oligoprogressive tumors were treated with SRT, and the same TKI therapy was continued afterward.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Competing risk analyses and the Kaplan-Meir methodology were used to report the outcomes of interest.

RESULTS AND LIMITATIONS

The median duration of TKI therapy prior to study entry was 18.6 mo; 1-yr LC of the irradiated tumors was 93% (95% confidence interval [CI] 71-98%). The median PFS after SRT was 9.3 mo (95% CI 7.5-15.7 mo). The cumulative incidence of changing systemic therapy was 47% (95% CI 32-68%) at 1 yr, with a median time to change in systemic therapy of 12.6 mo (95% CI 9.6-17.4 mo). One-year OS was 92% (95% CI 82-100%). There were no grade 3-5 SRT-related toxicities.

CONCLUSIONS

LC of irradiated oligoprogressive mRCC tumors was high, and the need to change systemic therapy was delayed for a median of >1 yr.

PATIENT SUMMARY

The use of stereotactic radiotherapy in metastatic kidney cancer patients, who develop growth of a few tumors while on oral targeted therapy, can significantly delay the need to change to the next line of drug therapy.

Metastasis-Directed Radiotherapy for Oligoprogressive or Oligopersistent Metastatic Colorectal Cancer

INTRODUCTION

Some patients with cancer may present with progressive or persistent disease at a limited number of sites following a period of treatment response. We evaluated the safety and effectiveness of metastasis-directed radiotherapy (MRT) for oligoprogressive or oligopersistent disease in patients receiving systemic treatment for metastatic colorectal cancer (mCRC).

PATIENTS AND METHODS

Patients with mCRC who received 5-fluorouracil, leucovorin, and oxaliplatin; 5-fluorouracil, leucovorin, and irinotecan; and/or capecitabine chemotherapy between 2011 and 2020 at a single institution were identified. Then, those who underwent MRT for five or fewer lesion sites while receiving systemic treatment for other metastases were categorized. The primary endpoint was time to change to systemic therapy. Secondary endpoints included MRT-related toxicity, overall survival, and local control.

RESULTS

Among 4157 patients included, 91 (2%) received MRT to limited lesion sites (55 oligoprogressive and 36 oligopersistent) during systemic treatment following a period of treatment response. The median time to change to next-line systemic therapy was 5 months in the overall cohort (measured from the current chemotherapy session) and 9.5 (range, 6.0-40.6) months in the MRT group (measured from the MRT session). No severe toxicity or systemic treatment interruption was observed following MRT. The 1-year local control and overall survival rates were 69% and 99%, respectively.

CONCLUSION

In patients with oligoprogressive or oligopersistent mCRC, MRT may be performed safely in conjunction with systemic treatment to maximize the benefit of systemic therapy and to prolong the time to change to systemic therapy. Further prospective studies should confirm these findings.

Better survival of patients with oligo- compared with polymetastatic cancers: a systematic review and meta-analysis of 173 studies

Background: The modern concept of oligometastatic (OM) state has been initially developed to describe patients with a low burden of disease and with a potential for cure with local ablative treatments. We systematically assessed the risk of death and relapse of oligometastatic (OM) cancers compared to cancers with more diffuse metastatic spread, through a meta-analysis of published data.  Methods: PubMed, the Cochrane Library, and EMBASE were searched for studies reporting prognosis of patients with OM solid tumors. Risk of death and relapse were extracted and pooled to provide an adjusted hazard ratio with a 95% confidence interval (HR 95%CI).  The primary outcome of the study refers to overall mortality in OM vs. polymetastatic (PM) patients.  Results. Mortality and relapse associated with OM state in patients with cancer were evaluated among 104,234 participants (n=173 studies). Progression-free survival was better in patients with OM disease (hazard ratio [HR] = 0.62, 95% CI 0.57-0.68; P <.001; n=69 studies). Also, OM cancers were associated with a better overall survival (OS) (HR = 0.65, 95% CI 0.62-0.68; P<.01; n=161 studies). In colorectal (CRC), breast, non-small cell lung cancer (NSCLC) and renal cell carcinoma (RCC) the reduction in the risk of death for OM patients were 35, 38, 30 and 42%, respectively. Biliary tract and cervical cancer do not significantly better in OM stage likely for paucity of data. Conclusions. Patients with OM cancers have a significantly better prognosis than those with more widespread stage IV tumors. In OM cancer patients a personalized approach should be pursued.