The use of radiation therapy for oligoprogressive/oligopersistent oncogene-driven non small cell lung cancer: State of the art

Navigating resistance to ALK inhibitors in the lorlatinib era: a comprehensive perspective on NSCLC

INTRODUCTION

The emergence of anaplastic lymphoma kinase (ALK) rearrangements in non-small cell lung cancer (NSCLC) has revolutionized targeted therapy. This dynamic landscape, featuring novel ALK inhibitors and combination therapies, necessitates a profound understanding of resistance mechanisms for effective treatment strategies. Recognizing two primary categories - on-target and off-target resistance - underscores the need for comprehensive assessment.

AREAS COVERED

This review delves into the intricacies of resistance to ALK inhibitors, exploring complexities in identification and management. Molecular testing, pivotal for early detection and accurate diagnosis, forms the foundation for patient stratification and resistance management. The literature search methodology involved comprehensive exploration of Pubmed and Embase. The multifaceted perspective encompasses new therapeutic horizons, ongoing clinical trials, and their clinical implications post the recent approval of lorlatinib.

EXPERT OPINION

Our expert opinion encapsulates the critical importance of understanding resistance mechanisms in the context of ALK inhibitors for shaping successful treatment approaches. With a focus on molecular testing and comprehensive assessment, this review contributes valuable insights to the evolving landscape of NSCLC therapy.

Novel Blood Biomarkers for Response Prediction and Monitoring of Stereotactic Ablative Radiotherapy and Immunotherapy in Metastatic Oligoprogressive Lung Cancer

Up to 80% of patients under immune checkpoint inhibitors (ICI) face resistance. In this context, stereotactic ablative radiotherapy (SABR) can induce an immune or abscopal response. However, its molecular determinants remain unknown. We present early results of a translational study assessing biomarkers of response to combined ICI and SABR (I-SABR) in liquid biopsy from oligoprogressive patients in a prospective observational multicenter study. Cohort A includes metastatic patients in oligoprogression to ICI maintaining the same ICI due to clinical benefit and who receive concomitant SABR. B is a comparative group of oligometastatic patients receiving only SABR. Blood samples are extracted at baseline (T1), after the first (T2) and last (T3) fraction, two months post-SABR (T4) and at further progression (TP). Response is evaluated by iRECIST and defined by the objective response rate (ORR)-complete and partial responses. We assess peripheral blood mononuclear cells (PBMCs), circulating cell-free DNA (cfDNA) and small RNA from extracellular vesicles. Twenty-seven patients could be analyzed (cohort A: n = 19; B: n = 8). Most were males with non-small cell lung cancer and one progressing lesion. With a median follow-up of 6 months, the last ORR was 63% (26% complete and 37% partial response). A decrease in cfDNA from T2 to T3 correlated with a good response. At T2, CD8+PD1+ and CD8+PDL1+ cells were increased in non-responders and responders, respectively. At T2, 27 microRNAs were differentially expressed. These are potential biomarkers of response to I-SABR in oligoprogressive disease.

Is oligoprogression a potentially curable disease in epidermal growth factor receptor mutant lung adenocarcinoma?

Third-generation epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) have shown impressive results in EGFR mutant lung cancer (LC) patients in terms of disease control rate with a positive impact on overall survival. Nevertheless, after months of treatment with targeted therapy, progression inevitably occurs. Some patients develop oligoprogression and local treatment is required for optimal disease control while maintaining EGFR-TKIs. This work features a clinical case of a patient harboring an EGFR mutant LC undergoing oligoprogression to EGFR-TKIs, first into the brain and afterward to the primary tumor, requiring local ablative strategies, including primary tumor resection three years after the start of osimertinib. Currently, the patient is still alive and continues with a complete response upon EGFR-TKIs maintenance. Hence, oligoprogression, even in driven oncogenic tumors, represents a distinct biological entity and potential curative disease that deserves particular consideration in multidisciplinary tumor boards. In this case, tumor primary resection after three years of the initial diagnosis represents a paradigm shift in the treatment of EGFR mutant patients.

Stereotactic Body Radiation Therapy for Oligoprogressive and Oligorecurrent Non-Small-Cell Lung Cancer

BACKGROUND AND PURPOSE

The role of stereotactic body radiation therapy (SBRT) in oligoprogressive non-small-cell lung cancer (NSCLC) is controversial. We evaluated whether SBRT in a subset of patients with oligoprogressive or oligorecurrent NSCLC offers a durable response, obviating the need to change systemic therapy.

METHODS

A retrospective analysis of 168 NSCLC patients who underwent SBRT for oligoprogressive or oligorecurrent disease was performed. Oligoprogression was defined as progression in ≤5 lesions during or after systemic therapy following an initial complete or partial response. Oligorecurrence was defined as progression while off systemic therapy. Progression-free survival (PFS), overall survival (OS) and time to next treatment or death (TNT-D) were estimated.

RESULTS

Median age was 68 years. Sixty-seven percent of patients were on systemic therapy at the time of progression. Progression at the primary site was present in 31% of the patients. The number of sites of metastatic progression was 0 to 2 in 76% and 3 to 5 in 24% of the patients. Two-year OS and PFS were 56% (95%CI 46%-64%) and 14% (95%CI 8%-21%), respectively. Median TNT-D was 9 months (95%CI 6-11). No grade 4 or 5 toxicity was seen. In multivariable analysis, patients with 3 to 5 sites of metastatic progression had worse OS (HR 2.6, 95%CI 1.5-4.3, P < .001) and shorter TNT-D (HR 1.7, 95%CI 1.1-2.5, P = .01) than those with 0 to 2 sites.

CONCLUSION

SBRT is a safe and viable treatment option for oligoprogressive and oligorecurrent NSCLC. Patients with 0 to 2 sites had better OS and longer TNT-D compared to those with 3 to 5 lesions.

Treatment patterns and clinical outcomes of extensive stage small cell lung cancer (SCLC) in the real-world evidence ESME cohort before the era of immunotherapy

BACKGROUND

Small cell lung cancer (SCLC) is a highly aggressive entity of lung cancer with tendency toward early recurrence after first-line treatment. As per recently updated European Society for Medical Oncology recommendations, first-line treatment with up to 4 cycles of platinum-etoposide combined with immune checkpoint inhibitor (ICIs)-targeting PD-L1, is now the standard of care. The purpose of the current analysis is to identify current patient profiles and treatment strategies in real life clinical practice, and report outcomes in Extensive Stage (ES)-SCLC.

METHODS

Non-interventional, retrospective, multicentre, comparative study was carried out to describe the outcome of ES-SCLC patients included in the Epidémiologie Stratégie Médico-Economique (ESME) data platform for advanced and metastatic lung cancer. Patients were selected from 34 health care facilities between January 2015 and December 2017, before the era of immunotherapy.

RESULTS

1315 patients were identified, including 64% male and 78% under 70 year-old; 24% had at least 3 metastatic sites, mainly liver metastases (43%), bone metastases (36%), brain metastases (32%). 49% received only one line of systemic treatment; 30% and 21% received 2 and 3 lines or more, respectively. Carboplatin was more frequently used than cisplatin (71% and 29%, respectively). Prophylactic cranial irradiation was infrequent (4% of patients), but 16% of patients received thoracic radiation therapy, mainly after the completion of first-line chemotherapy (72% of patients); such strategies were more frequently applied in cisplatin/etoposide than carboplatin/etoposide patients (p = 0.006 and p = 0.015, respectively). After a median follow-up time of 21.8 (95% CI: 20.9-23.3) months, median real-world Progression-Free Survival (rw-PFS) was 6.2 (95% CI: 5.7; 6.9) and 6.1 (95% CI: 5.8; 6.3) months for cisplatin/etoposide and carboplatin/etoposide doublet regimens, respectively; 24-month rwPFS and Overall Survival were 3.2% (95% CI: 2.3; 4;2) and 22.2% (95% CI: 19.4; 25.1) in the whole population, respectively.

CONCLUSION

Our data provide with landmark reference findings on ES-SCLC before the immunotherapy era, and cover many aspects of the treatment strategy, while highlighting on the role of radiotherapy, subsequent lines of therapy, and the outcomes of patients. Generation of real-world data focusing on patients who received platinum-based chemotherapy combined with immune checkpoint inhibitors is under way.

Long-term effectiveness and treatment sequences in patients with extensive stage small cell lung cancer receiving atezolizumab plus chemotherapy: Results of the IFCT-1905 CLINATEZO real-world study

BACKGROUND

Small cell lung cancer (SCLC) has a tendency towards recurrence and limited survival. Standard-of-care in 1st-line is platinum-etoposide chemotherapy plus atezolizumab or durvalumab,based on landmarkclinical trials.

METHODS

IFCT-1905 CLINATEZO is a nationwide, non-interventional, retrospectivestudy of patients with extensive-SCLC receivingatezolizumab plus chemotherapy as part of French Early Access Program. Objectives were to analyse effectiveness,safetyand subsequent treatments.

RESULTS

The population analyzed included 518 patients who received atezolizumabin 65 participating centers. There were 66.2% male,mean age was 65.7 years; 89.1% had a performance status (PS) 0/1 and 26.6% brain metastases. Almost all(95.9%) were smokers. Fifty-five (10.6%) received at least 1 previous treatment. Median number of atezolizumab injections was 7.0 (range [1.0-48.0]) for a median duration of 4.9 months (95% CI 4.5-5.1). Atezolizumab was continued beyond progression in 122 patients (23.6%) for a median duration of 1.9 months (95% CI: [1.4-2.3]). Best objective response was complete and partialin 19 (3.9%) and 378 (77.1%)patients. Stable diseasewas observed in 50 patients (10.2%). Median follow-up was30.8 months (95% CI: [29.9-31.5]). Median overall survival (OS), 12-, 24-month OS rates were 11.3 months (95% CI: [10.1-12.4]), 46.7% (95% CI [42.3-50.9]) and 21.2% (95% CI [17.7-24.8]). Median real-world progression-free survival, 6-, 12-month rates were 5.2 months (95% CI [5.0-5.4]), 37.5% (95% CI [33.3-41.7]) and 15.2% (95% CI [12.2-18.6]). For patients with PS 0/1, median OS was 12.2 months (95% CI [11.0-13.5]). For patients with previous treatment, median OS was 14.9 months (95% CI [10.1-21.5]). Three-hundred-and-twenty-six patients(66.4%) received subsequent treatment and27 (5.2%) were still underatezolizumabat date of last news.

CONCLUSIONS

IFCT-1905 CLINATEZO shows reproductibility, in real-life,ofIMpower-133survival outcomes, possibly attributed to selection of patients fit for this regimen, adoption of pragmatic approaches,including concurrent radiotherapy and treatment beyond progression.

What to do after immune-checkpoint inhibitors failure in advanced non-small cell lung cancer: an expert opinion and review

INTRODUCTION

Immune-checkpoint inhibitors (IO) have significantly improved outcomes of patients with non-oncogene-addicted non-small cell lung cancer (NSCLC), becoming the first-line agents for advanced disease. However, resistance remains a significant clinical challenge, limiting their effectiveness.

AREAS COVERED

Hereby, we addressed standard and innovative therapeutic approaches for NSCLC patients experiencing progression after IO treatment, discussing the emerging resistance mechanisms and the ongoing efforts to overcome them. In order to provide a complete overview of the matter, we performed a comprehensive literature search across prominent databases, including PubMed, EMBASE (Excerpta Medica dataBASE), and the Cochrane Library, and a research of the main ongoing studies on clinicaltrials.gov.

EXPERT OPINION

The dynamics of progression to IO, especially in terms of time to treatment failure and burden of progressive disease, should guide the best subsequent management, together with patient clinical conditions. Long-responders to IO might benefit from continuation of IO beyond-progression, in combination with other treatments. Patients who experience early progression should be treated with salvage CT in case of preserved clinical conditions. Finally, patients who respond to IO for a considerable timeframe and who later present oligo-progression could be treated with a multimodal approach in order to maximize the benefit of immunotherapy.

Accelerated hypofractionated magnetic resonance-guided adaptive radiotherapy for oligoprogressive non-small cell lung cancer

Given the positive results from recent randomized controlled trials in patients with oligometastatic, oligoprogressive, or oligoresidual disease, the role of radiotherapy has expanded in patients with metastatic non-small cell lung cancer (NSCLC). While small metastatic lesions are commonly treated with stereotactic body radiotherapy (SBRT), treatment of the primary tumor and involved regional lymph nodes may require prolonged fractionation schedules to ensure safety especially when treating larger volumes in proximity to critical organs-at-risk (OARs). We have developed an institutional MR-guided adaptive radiotherapy (MRgRT) workflow for these patients. We present a 71-year-old patient with stage IV NSCLC with oligoprogression of the primary tumor and associated regional lymph nodes in which MR-guided, online adaptive radiotherapy was performed, prescribing 60 Gy in 15 fractions. We describe our workflow, dosimetric constraints, and daily dosimetric comparisons for the critical OARs (esophagus, trachea, and proximal bronchial tree [PBT] maximum doses [D0.03cc]), in comparison to the original treatment plan recalculated on the anatomy of the day (i.e., predicted doses). During MRgRT, few fractions met the original dosimetric objectives: 6.6% for esophagus, 6.6% for PBT, and 6.6% for trachea. Online adaptive radiotherapy reduced the cumulative doses to the structures by 11.34%, 4.2%, and 5.62% when comparing predicted plan summations to the final delivered summation. Therefore, this case study presets a workflow and treatment paradigm for accelerated hypofractionated MRgRT due to the significant variations in daily dose to the central thoracic OARs to reduce treatment-related toxicity associated with radiotherapy.

Rationale and value of consolidative cranial local therapy in EGFR-mutant non-small cell lung cancer patients with baseline brain metastasis treated with first-line EGFR-TKIs

Objectives

To explore the rationale and value of consolidative cranial local therapy (CLT) in epidermal growth factor receptor (EGFR)-mutant non-small cell lung cancer (NSCLC) patients with brain metastases (BMs).

Methods

EGFR-mutant NSCLC patients with baseline BMs who received first-line EGFR-tyrosine kinase inhibitors (TKIs) at two academic centers from May 2015 to June 2020 were retrospectively enrolled. Patterns of tumor response and treatment failure were extensively analyzed in order to explore the rationale of CLT. Cranial lesions with number ⩽3 and largest tumor size ⩽3 cm at baseline and best response to EGFR-TKIs were defined as oligo-BMs and oligo-residual cranial disease (ORCD), respectively. To provide preliminary data supporting CLT, survival outcomes were compared in patients with ORCD, stratified by CLT status.

Results

Of the 216 patients enrolled, 57.1% had oligo-BMs and 24.5% received first-line osimertinib. At best response to the first-line EGFR-TKIs, intracranial complete response, partial response, and stable disease occurred in 18.5, 31.9, and 44.4% of the whole population, respectively. For patients without CLT (n = 193), ORCD was observed in 78.1% of the 105 patients with baseline oligo-BMs and 10.2% of the 88 patients with baseline multiple-BMs. With a median follow-up of 22.8 months, 107 patients had cranial first progressive disease (PD); more than 60% developed their first PD solely from the residual tumor sites at best response to EGFR-TKIs. Moreover, among patients with ORCD (n = 108), patients who received CLT (n = 17) achieved significantly longer progression-free survival (13.4 versus 8.5 months, p = 0.001) and overall survival (58.9 versus 28.8 months, p = 0.021) than those without CLT. Meanwhile, CLT remained as an independent prognostic factor associated with improved survival after Cox regression analyses.

Conclusions

Cranial progressive disease developed mostly at the residual cranial lesions in EGFR-mutant NSCLC patients with baseline BMs who received first-line EGFR-TKIs. Consolidative cranial local therapy targeting the oligo-residual cranial tumor lesions may provide survival benefit, which warrants future validation.

Clinical Effects of Immuno-Oncology Therapy on Glioblastoma Patients: A Systematic Review

The most prevalent and deadly primary malignant glioma in adults is glioblastoma (GBM), which has a median survival time of about 15 months. Despite the standard of care for glioblastoma, which includes gross total resection, high-dose radiation, and temozolomide chemotherapy, this tumor is still one of the most aggressive and difficult to treat. So, it is critical to find more potent therapies that can help glioblastoma patients have better clinical outcomes. Additionally, the prognosis for recurring malignant gliomas is poor, necessitating the need for innovative therapeutics. Immunotherapy is a rather new treatment for glioblastoma and its effects are not well studied when it is combined with standard chemoradiation therapy. We conducted this study to evaluate different glioblastoma immunotherapy approaches in terms of feasibility, efficacy, and safety. We conducted a computer-assisted literature search of electronic databases for essays that are unique, involve either prospective or retrospective research, and are entirely written and published in English. We examined both observational data and randomized clinical trials. Eighteen studies met the criteria for inclusion. In conclusion, combining immunotherapy with radiochemotherapy and tumor removal is generally possible and safe, and rather effective in the prolongation of survival measures.

Thoracic Radiotherapy in Extensive Disease Small Cell Lung Cancer: Multicenter Prospective Observational TRENDS Study

(1) Introduction: Small cell lung cancer (SCLC) is an aggressive tumor type, accounting for about 15% of all lung cancers. Radiotherapy (RT) plays a fundamental role in both early and advanced stages. Currently, in advanced disease, the use of consolidative chest RT should be recommended for patients with good response to platinum-based first-line chemotherapy, but its use has not yet been standardized. The present prospective study aims to evaluate the pattern of care of consolidative chest RT in patients with advanced stage SCLC, and its effectiveness in terms of disease control and tolerability. (2) Materials and methods: This study was a multicenter prospective observational trial, proposed and conducted within the AIRO lung study group to evaluate the pattern of care of consolidative chest RT after first-line chemotherapy in patients with advanced SCLC. The patient and tumor characteristics, doses, fractionation and volumes of thoracic RT and prophylactic cranial irradiation (PCI), as well as the thoracic and extrathoracic response to the treatment, toxicity and clinical outcomes, were collected and analyzed. (3) Results: From January 2017 to December 2019, sixty-four patients were enrolled. Median follow-up was 33 months. The median age was 68 years (range 42-81); 38 patients (59%) were male and 26 (41%) female. Carboplatin + etoposide for 6 cycles was the most commonly used first-line therapeutic scheme (42%). With regard to consolidative chest RT, 56% of patients (35) received 30 Gy in 10 factions and 16 patients (26%) received 45 Gy in 15 sessions. The modulated intensity technique was used in 84.5% of cases, and post-chemotherapy macroscopic residual disease was the target volume in 87.5% of patients. Forty-four patients (69%) also underwent PCI. At the last follow-up, over 60% of patients did not experience chest disease progression, while 67% showed extrathoracic progression. At the first radiological evaluation after RT, complete response and stable disease were recorded in 6% and 46% of the cases, respectively. Two patients had a long-term complete response to the combined treatment. The brain was the first site of extrathoracic progression in 28%. 1y and 2y OS and PFS were 67%, 19%, 28% and 6%, respectively. Consolidative chest RT was well-tolerated in the majority of patients; it was interrupted in three cases (due to G2 pulmonary toxicity, disease progression and clinical decay, respectively). Only 1 patient developed G3 asthenia. (4) Conclusions: Consolidative chest RT has been shown to be useful in reducing the risk of thoracic disease progression and is absolutely well-tolerated in patients with advanced stage SCLC with good response after first-line chemotherapy. Among the Italian centers that participated in this study, there is still variability in the choice of fractionation and target volumes, although the guidelines contain clear recommendations. The aim of future research should be to clarify the role and modalities of chest RT in the era of immunotherapy in advanced-stage SCLC.

Immunotherapy resistance in non-small-cell lung cancer: From mechanism to clinical strategies

The high primary resistance incidence and unavoidable secondary resistance are the major clinical obstacle to lasting long-term benefits in Non-small-cell lung cancer (NSCLC) patients treated with immunotherapy. The mechanisms of immunotherapy resistance in NSCLC are complex, mainly involving tumor cells and tumor microenvironment (TME) infiltrating immune cells, including TAMs, B cells, NK cells, and T cells. The selection of clinical strategies for NSCLC progression after immunotherapy resistance should depend on the progressive mode. The progression pattern of NSCLC patients after immunotherapy resistance can be divided into oligo-progression and systemic/multiple progression, which should be considered for further treatment selection. In the future, it needs to explore how to optimize the combined therapy and explore strategies to reprogram infiltrating immune cells under various genetic backgrounds of tumor cells and timely reshape TME during antitumor treatments.

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.

Clinical value of PET/CT in identifying patients with oligometastatic/oligoprogressive disease among first-line tyrosine kinase inhibitor-treated advanced EGFR-mutant non-small cell lung cancer: Implications from survival comparisons

OBJECTIVE

Local therapy (LT) could potentially prolong the survival of patient with advanced epidermal growth factor receptor (EGFR)-mutant non-small cell lung cancer (NSCLC) receiving tyrosine kinase inhibitors (TKIs) and harboring oligometastatic/oligoprogressive disease (OMD/OPD). However, the optimal imaging method for identifying patients with OMD/OPD remains controversial. The objective of this study was to investigate the clinical value of incorporating PET/CT in detecting patients with OMD/OPD.

METHODS

Consecutive cases with metastatic EGFR-mutant NSCLC undergoing first-line EGFR-TKI treatment were retrospectively screened and those receiving baseline PET/CT and brain magnetic resonance imaging (MRI) or complete conventional imaging (CIM), including brain MRI, chest computed tomography (CT), abdomen ultrasound or CT and bone scintigraphy were included. OMD/OPD was defined as metastases/progressions documented at a maximum of five lesions and three organs, otherwise was defined as multiple metastatic/progressive disease (MMD/MPD). Progression-free survival (PFS) and overall survival (OS) were analyzed.

RESULTS

Of the 392 patients evaluated, baseline OMD was detected in 22.7% (53/233) of patients by PET/CT and in 18.2% (29/159) of patients by CIM (p = 0.171). Among the patients evaluated with baseline PET/CT, patients with OMD had longer PFS (p = 0.016) and tendency of improved OS (p = 0.058) than those with MMD. However, this result was not observed with patients evaluated using baseline CIM. With a median follow-up of 24.2 (range, 1.1-124.6) months, 297 patients had their first disease progression (FPD), of whom 164 (55.2%) had adequate imaging scans to analyze the tumor distributions at FPD comprehensively. OPD was detected in 63.0% (34/54) and 35.0% (39/110) of patients among the PET/CT and CIM assessed group (p = 0.003), respectively. Among the PET/CT assessed group, patients with OPD had significantly longer post-progressive overall survival (OS2) than those with MPD (p = 0.011). However, no significant difference of OS2 in the CIM assessed group was found.

CONCLUSION

Patients with OMD/OPD, evaluated by PET/CT but not CIM, generally had more favorable survival outcomes than those with MMD/MPD among patients with metastatic NSCLC undergoing first-line EGFR-TKI treatment.

ADVANCES IN KNOWLEDGE

PET/CT seems to affect the survival of patients under first-line EGFR-TKI treated metastatic NSCLC with OMD/OPD.

Impact of stereotactic body radiotherapy (SBRT) in oligoprogressive metastatic disease

PURPOSE

There is increasing interest in using stereotactic body radiation therapy (SBRT) in areas of oligoprogressive metastatic disease (OPD). Our main objective was to investigate the impact of SBRT on overall survival (OS) and the incidence of systemic therapy treatment switches in this population.

METHODS

A retrospective institutional review of patients treated with SBRT for OPD was performed. Patients were included if they received SBRT for 1-3 discrete progressing metastases, using a dose of at least 5 Gy per fraction. The study aimed to calculate progression-free survival (PFS), overall survival (OS), local control (LC), and incidence of treatment switch (TS). PFS and OS were calculated using the Kaplan-Meier methodology, while LC and TS were determined using cumulative incidence.

RESULTS

Eighty-one patients with a total of 118 lesions were treated with SBRT from July 2014 to November 2020. The Median SBRT dose was 40 (18-60) Gy in 5 (2-8) fractions. Patients had primarily kidney, lung, or breast cancer. Most patients were treated with a tyrosine kinase inhibitor (TKI) (30.9%) or chemotherapy (29.6%) before OPD. The median follow-up post-SBRT was 14 months. Median OS and PFS were 25.1 (95% CI 11.2-39.1) months and 7.8 (95% CI 4.6-10.9) months, respectively. The cumulative incidence of local progression of treated lesions was 5% at 1 year and 7.3% at 2 years. Sixty patients progressed after SBRT and 17 underwent additional SBRT. Thirty-eight patients (47%) changed systemic therapy following SBRT; the cumulative incidence of TS was 28.5% at 6 months, 37.4% at 1 year, and 43.9% at 2 years.

CONCLUSIONS

SBRT effectively controls locally progressing lesions but distant progression still occurs frequently. A sizeable number of patients can be salvaged by further SBRT or have minimally progressing diseases that may not warrant an immediate initiation/switch in systemic therapy. Further prospective studies are needed to validate this benefit.

Stereotactic Body Radiation Therapy (SBRT) for Oligorecurrent/Oligoprogressive Mediastinal and Hilar Lymph Node Metastasis: A Systematic Review

Simple Summary

This paper is a review of the literature on oligorecurrent/oligoprogressive mediastinal and hilar lymph node metastasis treated with SBRT. The use of mediastinal SBRT had historically been not feasible in view of the expected toxicity due to the proximity of critical structures such as the airways and esophagus. Despite the heterogeneity and lack of some data in the studies analyzed, this literature review is the first published and can be a valid guide for the radiotherapist in the management of oligometastatic/oligoprogressive patients, with particular regard to the radiotherapy doses, dose constraints for organs at risk, and clinical outcomes.

Abstract

Introduction: Mediastinal or hilar lymph node metastases are a challenging condition in patients affected by solid tumors. Stereotactic body radiation therapy (SBRT) could play a crucial role in the therapeutic management and in the so-called “no-fly zone”, delivering high doses of radiation in relatively few treatment fractions with excellent sparing of healthy surrounding tissues and low toxicity. The aim of this systematic review is to evaluate the feasibility and tolerability of SBRT in the treatment of mediastinal and hilar lesions with particular regard to the radiotherapy doses, dose constraints for organs at risk, and clinical outcomes. Materials and methods: Two blinded investigators performed a critical review of the Medline, Web of Knowledge, Google Scholar, Scopus, and Cochrane databases according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement (PRISMA), starting from a specific question: What is the clinical impact of SBRT for the treatment of oligorecurrent/oligoprogressive mediastinal and hilar metastasis? All retrospective and prospective clinical trials published in English up to February 2022 were analyzed. Results: A total of 552 articles were identified and 12 of them were selected with a total number of 478 patients treated with SBRT for mediastinal or hilar node recurrence. All the studies are retrospective, published between 2015 and 2021 with a median follow-up ranging from 12 to 42.2 months. Studies following SBRT for lung lesions or retreatments after thorax radiotherapy for stage III lung cancer were also included. The studies showed extensive heterogeneity in terms of patient and treatment characteristics. Non-small cell lung cancer was the most frequently reported histology. Different dose schemes were used, with a higher prevalence of 4–8 Gy in 5 or 6 fractions, but dose escalation was also used up to 52 Gy in 4 fractions with dose constraints mainly derived from RTOG 0813 trial. The radiotherapy technique most frequently used was volumetric modulated arc therapy (VMAT) with a median PTV volume ranging from 7 to 25.7 cc. The clinical outcome seems to be very encouraging with 1-year local control (LC), overall survival (OS) and progression-free survival (PFS) rates ranging from 84 to 94%, 53 to 88% and 23 to 53.9%, respectively. Half of the studies did not report toxicity greater than G3 and only five cases of fatal toxicity were reported. CONCLUSIONS: From the present review, it is not possible to draw definitive conclusions because of the heterogeneity of the studies analyzed. However, SBRT appears to be a safe and effective option in the treatment of mediastinal and hilar lymph node recurrence, with a good toxicity profile. Its use in clinical practice is still limited, and there is extensive heterogeneity in patient selection and fractionation schedules. Good performance status, small PTV volume, absence of previous thoracic irradiation, and administration of a high biologically effective dose (BED) seem to be factors that correlate with greater local control and better survival rates. In the presence of symptoms related to the thoracic lymph nodes, SBRT determines a rapid control that lasts over time. We look forward to the prospective studies that are underway for definitive conclusions.

The Value of Radiotherapy for Advanced Non-Small Cell Lung Cancer With Oncogene Driver-Mutation

Due to the widespread use of tyrosine kinase inhibitors (TKIs), which have largely supplanted cytotoxic chemotherapy as the first-line therapeutic choice for patients with advanced non-small cell lung cancer (NSCLC) who have oncogene driver mutations, advanced NSCLC patients with oncogene driver mutations had much long median survival. However, TKIs’ long-term efficacy is harmed by resistance to them. TKIs proved to have a limited potential to permeate cerebrospinal fluid (CSF) as well. Only a small percentage of plasma levels could be found in CSF at usual doses. Therefore, TKIs monotherapy may have a limited efficacy in individuals with brain metastases. Radiation has been demonstrated to reduce TKIs resistance and disrupt the blood-brain barrier (BBB). Previous trials have shown that local irradiation for bone metastases might improve symptoms, in addition, continuous administration of TKIs combined with radiotherapy was linked with beneficial progression-free survival (PFS) and overall survival (OS) for oligometastasis or bone metastasis NSCLC with oncogene driver mutations. The above implied that radiotherapy combined with targeted therapy may have a synergistic impact in patients with advanced oncogene driver-mutated NSCLC. The objective of this article is to discuss the value of radiotherapy in the treatment of those specific individuals.

State of the Art in Combination Immuno/Radiotherapy for Brain Metastases: Systematic Review and Meta-Analysis

Objectives: Common origins for brain metastases (BMs) are melanoma, lung, breast, and renal cell cancers. BMs account for a large share of morbidity and mortality caused by these cancers. The advent of new immunotherapeutic treatments has made a revolution in the treatment of cancer patients and particularly, as a new concept, if it is combined with radiotherapy, may lead to considerably longer survival. This systematic review and meta-analysis aimed to evaluate the survival rate and toxicities of such a combination in brain metastases. Methods: To perform a systematic review of the literature until January 2021 using electronic databases such as PubMed, Cochrane Library, and Embase; the Newcastle–Ottawa Scale was used to evaluate the quality of cohort studies. For data extraction, two reviewers extracted the data blindly and independently. Hazard ratio with 95% confidence interval (CI), fixed-effect model, and inverse-variance method was calculated. The meta-analysis has been evaluated with the statistical software Stata/MP v.16 (The fastest version of Stata). Results: In the first step, 494 studies were selected to review the abstracts, in the second step, the full texts of 86 studies were reviewed. Finally, 28 studies were selected consisting of 1465 patients. The addition of IT to RT in the treatment of brain metastasis from melanoma and non-small-cell lung carcinoma was associated with a 39% reduction in mortality rate and has prolonged overall survival, with an acceptable toxicity profile. The addition of IT to RT compared with RT alone has a hazard ratio of 0.39(95% CI 0.34–0.44). Conclusions: A combination of immuno/radiotherapy (IR) for the treatment of patients with BMs from melanoma and non-small-cell lung carcinoma has prolonged overall survival and reduced mortality rate, with acceptable toxicity. In terms of timing, RT seems to have the best effect on the result when performed before or simultaneously with immunotherapy.

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.

Efficacy and acquired resistance for EGFR-TKI plus thoracic SBRT in patients with advanced EGFR-mutant non-small-cell lung cancer: a propensity-matched retrospective study

Background

This retrospective study aimed to evaluate the efficacy of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) with stereotactic body radiation therapy (SBRT) and to elucidate potential mechanisms of acquired resistance.

Methods

Patients with advanced NSCLC harboring positive EGFR mutations after initial TKI therapy for at least 8 weeks were eligible for SBRT between August 2016 and August 2019. Eligible patients were treated with thoracic SBRT, and TKI was continued after SBRT until it was considered ineffective. The control group was treated with TKIs monotherapy. Propensity score matching (PSM, ratio of 1:2) was used to account for differences in baseline characteristics. Overall survival (OS), progression-free survival (PFS), treatment safety and resistance mechanisms were evaluated.

Results

Three hundred eight patients were included in the study population. Among them, 262 patients received TKIs alone, and 46 patients received TKIs with SBRT. Baseline characteristics were not significantly different between the two cohorts after PSM. The median PFS was 19.4 months in the TKIs +SBRT group compared to 13.7 months in the TKIs group (p = 0.034). An influence on OS has not yet been shown (p = 0.557). Of the 135 patients evaluated after PSM, 28 and 71 patients in the TKIs and TKIs +SBRT cohorts, respectively, had plasma cell-free DNA (cfDNA) next-generation sequencing (NGS) performed at baseline and disease progression. In the TKIs +SBRT cohort, the NGS results showed that T790M mutations were detected in 64.3% (18/28) of patients. Patients in the TKIs cohort exhibited fewer T790M-positive mutations (40.8%, p = 0.035) compared to patients in the TKIs +SBRT cohort.

Conclusion

Real world data prove that TKIs plus thoracic SBRT significantly extend PFS with tolerable toxicity. The mutation ratio of T790M was increased in the TKIs +SBRT group compared to the TKIs only group. Further randomized studies are warranted.

Personal and Prognostic: Tissue and Liquid Biomarkers of Radiotherapeutic Response in Non-Small Cell Lung Cancer

Recent treatment advances have improved outcomes for patients with non-small cell lung cancer (NSCLC), often utilizing tumor molecular characterization to identify targetable mutations. This is further enhanced by advancements in "liquid biopsies", using peripheral blood for noninvasive, serial sampling of tumor biology. While tumor genomic alterations have established therapeutic implications in metastatic NSCLC, research is also ongoing to develop applications for tissue and liquid biomarkers in earlier stage disease, such as patients treated with radiation for early stage or locoregional NSCLC.

Beyond First-Line Immunotherapy: Potential Therapeutic Strategies Based on Different Pattern Progressions: Oligo and Systemic Progression

First-line immune-checkpoint inhibitor (ICI)-based therapy has deeply changed the treatment landscape and prognosis in advanced non-small cell lung cancer (aNSCLC) patients with no targetable alterations. Nonetheless, a percentage of patients progressed on ICI as monotherapy or combinations. Open questions remain on patients' selection, the identification of biomarkers of primary resistance to immunotherapy and the treatment strategies to overcome secondary resistance to first-line immunotherapy. Local ablative approaches are the main therapeutic strategies in oligoprogressive disease, and their role is emerging in patients treated with immunotherapy. Many therapeutic strategies can be adapted in aNSCLC patients with systemic progression to personalize the treatment approach according to re-characterization of the tumors, previous ICI response, and type of progression. This review's aim is to highlight and discuss the current and potential therapeutic approaches beyond first-line ICI-based therapy in aNSCLC patients based on the pattern of disease progression (oligoprogression versus systemic progression).

Long-term disease outcome and volume-based decision strategy in a large cohort of multiple brain metastases treated with a mono-isocentric linac-based Stereotactic Radiosurgery technique

PURPOSE

Radiosurgery (SRS) is an effective treatment option for brain metastases (BMs). Long-term results of the first worldwide experience with a mono-isocentric, non-coplanar, linac-based stereotactic technique in the treatment of multiple BMs are reported.

METHODS

patients with multiple BMs, life expectancy > 3 months, and good performance status (≤ 2) were treated with simultaneous SRS with volumetric modulated arc technique. Data were retrospectively evaluated.

RESULTS

172 patients accounting for 1079 BMs were treated at our institution from 2017 to 2020. The median number of treated metastases was 4 (range 2-22). Primary tumor histology was: lung (44.8%), breast (32%), and melanoma (9.4%). The 2-year LPFS was 71.6%, respectively. A biological effective dose (BED) ≥ 51.3 Gy₁₀ correlated with higher local control. Uncontrolled systemic disease and melanoma histology were independent prognostic factors correlated with decreased iPFS. Patients with > 10 BMs had a trend towards shorter iPFS (p = 0.055). 31 patients received multiple SRS courses (2-7) in case of intracranial progression. The median iOS was 22.4 months. Brainstem metastases and total PTV > 7.1 cc correlated with shorter iOS. The 1- and 2-year WBRT-free survival was 83.2% and 61.1%, respectively.

CONCLUSION

Long-term results in a large patient population treated with a mono-isocentric, dedicated technique demonstrated its effectiveness and safety also in the case of multiple courses. The shortened treatment time and the possibility to safely spare healthy brain tissue allows the safe treatment of patients with a large number of metastases and to deliver multiple courses of SRS. In selected cases, the administration of WBRT can be delayed.

A narrative review of evolving roles of radiotherapy in advanced non-small cell lung cancer: from palliative care to active player

Radiotherapy, along with other loco-regional interventions, is conventionally utilized as a palliative approach to alleviate symptoms and mitigate oncological emergencies in advanced non-small cell lung cancer (NSCLC). Thanks to the ongoing improvement of medical treatments in the last decade, such as targeted therapy and immunotherapy, the survival of patients with advanced NSCLC has been considerably prolonged, making it feasible and clinically beneficial for radiotherapy to play a more active role in highly selected subpopulations. In this review, we will focus on the evolving roles of radiotherapy in advanced NSCLC. First of all, among patients who are initially unable to tolerate aggressive treatment due to severe symptoms caused by metastases and/or tumor emergencies, timely radiotherapy could significantly improve their performance status (PS) and general condition, thus giving them a chance for intensive treatment and prolonged survival. The efficacy, potential candidates, and optimal dose-fractionation regimens of radiotherapy in this clinical scenario will be discussed. Additionally, radiotherapy can play a curative role as a concurrent therapy, consolidation therapy, and salvage therapy for patients with oligo-metastatic, oligo-residual, and oligo-progressive disease, respectively. Accumulating evidence from recent clinical trials, basic research, and translational investigations regarding the potentially curative roles of radiotherapy in NSCLC patients with oligo-metastatic disease will be summarized. Moreover, with the advent of various small molecular tyrosine kinase inhibitors (TKIs), the treatment efficacy and overall survival of oncogene-addicted NSCLC with brain metastases have been significantly improved, and the clinical value and optimal timing of cranial radiotherapy have become topics of much debate. Finally, synergistic antitumor interactions between radiotherapy and immunotherapy have been repeatedly demonstrated. Thus, the immune sensitizing role of radiotherapy in advanced NSCLC is also highlighted in this review.