Defining oligometastatic disease from a radiation oncology perspective: An ESTRO-ASTRO consensus document

Exploring the Evolving Landscape of Stereotactic Body Radiation Therapy in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) carries significant morbidity and mortality. Management of the HCC requires a multidisciplinary approach. Surgical resection and liver transplantation are the gold standard options for the appropriate settings. Stereotactic body radiation therapy (SBRT) has emerged as a promising treatment modality in managing HCC; its use is more studied and well-established in advanced HCC (aHCC). Current clinical guidelines universally endorse SBRT as a viable alternative to radiofrequency ablation (RFA), transarterial chemoembolisation (TACE), and transarterial radioembolisation (TARE), a recommendation substantiated by literature demonstrating comparable efficacy among these modalities. In early-stage HCC, SBRT primarily manages unresectable tumours unsuitable for ablative procedures such as microwave ablation and RFA. SBRT has been incorporated as a modality to downstage tumours or as a bridge to transplant. In the case of intermediate or advanced HCC, SBRT offers excellent results either as a single modality or adjunct to other locoregional modalities such as TACE/TARE. Recent data from late-stage HCC patients illustrate the effectiveness of SBRT in achieving local tumour control while minimising damage to surrounding healthy liver tissue. It has promising local control of approximately 80-90% in managing HCC. Additional prospective data comparing the efficacy of SBRT with the first-line recommended therapies such as RFA, TACE, and surgery are essential. The standard of care for patients with advanced/metastatic disease is systemic therapy (immunotherapy/tyrosine kinase inhibitors). SBRT, in combination with immune-checkpoint inhibitors, has an immune-modulatory effect that results in a synergistic effect. Recent findings indicate that the combination of immunotherapy and SBRT in HCC is well-tolerated and exhibits synergistic effects. Further exploration of diverse immunotherapy and radiotherapy strategies is essential to identify the appropriate time for combination treatments and to optimise dose and fraction regimens. Prospective, randomised studies are imperative to establish SBRT as the primary treatment for HCC.

OligoM-Cancer: A multidimensional information platform for deep phenotyping of heterogenous oligometastatic cancer

Patients with oligometastatic cancer (OMC) exhibit better response to local therapeutic interventions and a more treatable tendency than those with polymetastatic cancers. However, studies on OMC are limited and lack effective integration for systematic comparison and personalized application, and the diagnosis and precise treatment of OMC remain controversial. The application of large language models in medicine remains challenging because of the requirement of high-quality medical data. Moreover, these models must be enhanced using precise domain-specific knowledge. Therefore, we developed the OligoM-Cancer platform (http://oligo.sysbio.org.cn), pioneering knowledge curation that depicts various aspects of oligometastases spectrum, including markers, diagnosis, prognosis, and therapy choices. A user-friendly website was developed using HTML, FLASK, MySQL, Bootstrap, Echarts, and JavaScript. This platform encompasses comprehensive knowledge and evidence of phenotypes and their associated factors. With 4059 items of literature retrieved, OligoM-Cancer includes 1345 valid publications and 393 OMC-associated factors. Additionally, the included clinical assistance tools enhance the interpretability and credibility of clinical translational practice. OligoM-Cancer facilitates knowledge-guided modeling for deep phenotyping of OMC and potentially assists large language models in supporting specialised oligometastasis applications, thereby enhancing their generalization and reliability.

Stereotactic ablative radiotherapy for oligoprogressive solid tumours: A systematic review and meta-analysis

INTRODUCTION

The aim of this systematic review and meta-analysis was to review evidence and pool outcomes to assess the effectiveness of stereotactic ablative radiotherapy (SABR) in patients treated for oligoprogressive metastases.

METHODS AND MATERIALS

A search was conducted January 2010 to January 2023 in five bibliographic databases for studies of patients with oligoprogressive disease treated with SABR to all lesions. Clinical outcomes included PFS (progression-free survival), OS (overall survival) and CST (change in systemic therapy). Descriptive statistics were used to summarize the data. Binary random effects model was used for pooled analyses.

RESULTS

12,366 titles/abstracts screened, of which 25 met eligibility criteria and were included the review. All studies were published after 2017 with approximately 80% of the publications in 2021 and 2022. The primary tumour was prostate (n=8, 32%), kidney (n=6, 24%), colorectal (n=4, 16%) followed by breast (n=3, 12%), lung (n=2, 8%) and mixed (n=3, 12%). At 1 year, the pooled PFS was 44% (95% confidence interval [CI]: 34-53%, I2=91%); 53% (95% CI: 45-60%, I2=46%) in prostate, 49% (95% CI: 33-65%, I2=88%) in kidney, 62% (95% CI: 11-113%, I2=96%) in lung, 13% (95% CI: 3-24%, I2=39%) in breast and 30% (95% CI: 19-41%, I2=59%) in mixed.

DISCUSSION

There has been a surge in publications describing the use of SABR in oligoprogressive tumours. Published studies are mostly retrospective reported in prostate and kidney cancers, with limited evidence in other sites. Universal guidelines are recommended to ensure consistency in reporting and comparability of future studies.

Local Ablative Therapy Combined With Pembrolizumab in Patients With Synchronous Oligometastatic Non-Small Cell Lung Cancer: A Recursive Partitioning Analysis

PURPOSE

This study aimed to evaluate the efficacy of local ablative therapy (LAT) combined with pembrolizumab in patients with synchronous oligometastatic non-small cell lung cancer (NSCLC) and to identify patients who would most benefit from LAT.

METHODS AND MATERIALS

We retrospectively identified patients who received diagnosis of synchronous oligometastatic NSCLC (≤5 metastatic lesions and ≤3 organs involved) and were treated with first-line pembrolizumab between January 2017 and December 2022. Patients who underwent LAT, including surgery or radiation therapy at all disease sites, were compared with those who did not undergo LAT. A recursive partitioning analysis (RPA) model was developed using prognostic factors for progression-free survival (PFS).

RESULTS

Among the 258 patients included, 78 received LAT with pembrolizumab, and 180 received pembrolizumab alone. The median follow-up duration was 15.5 months (range, 3.0-71.2 months). In the entire cohort, LAT was independently associated with significantly improved PFS (hazard ratio [HR], 0.64; P = .015) and overall survival (OS) (HR, 0.61; P = .020). In the propensity score-matched cohort (N = 74 in each group), the median PFS was 19.9 months and 9.6 months, respectively (P = .003), and the median OS was 42.2 months and 20.5 months, respectively (P = .045), for the LAT and non-LAT groups. Based on the RPA model, incorporating the number of metastatic lesions, performance status, and programmed cell death-ligand 1 expression level, patients were stratified into 3 risk groups with distinct PFS. LAT significantly improved PFS and OS in the low- and intermediate-risk groups; however, no difference was observed in the high-risk group. LAT was more effective as a consolidative treatment after pembrolizumab initiation than as an upfront therapy.

CONCLUSIONS

LAT combined with pembrolizumab was associated with higher PFS and OS compared with pembrolizumab alone in selected patients with synchronous oligometastatic NSCLC. The RPA model could serve as a valuable clinical tool for identifying appropriate patients for LAT.

Role of stereotactic radiotherapy in the management of small-cell lung cancer

Small-cell lung cancer is the most aggressive form of lung neoplasia, treated in recent decades with chemoradiotherapy in case of limited stage and chemotherapy alone at the metastatic stage. In the last few years, the advent of immunotherapy has changed the landscape in the treatment of non-small-cell lung cancer, and to a lesser degree in small-cell lung cancer. Despite the recent advances in research, small-cell lung cancer is still considered an aggressive and lethal disease characterized by high recurrence or metastatic potential. As stereotactic radiotherapy has established itself as the standard of care in the early stage of inoperable non-small-cell lung cancer and in metastatic disease to treat brain and extracranial metastases, these same issues now arise in the management of small-cell lung cancer. This article aims to review the current knowledge and the potential of stereotactic radiotherapy in small-cell lung cancer.

Tailoring neoadjuvant systemic therapy in breast cancer: "The advent of a personalized approach"-The Breast-Gynecological and Immuno-Oncology International Cancer Conference (BGICC) consensus and recommendations

BACKGROUND

The management of early breast cancer (BC) has witnessed an uprise in the use of neoadjuvant therapy and a remarkable reshaping of the systemic therapy postneoadjuvant treatment in the last few years, with the evolution of many controversial clinical situations that require consensus.

METHODS

During the 14th Breast-Gynecological and Immuno-Oncology International Cancer Conference held in Egypt in 2022, a panel of 44 BC experts from 13 countries voted on statements concerning debatable challenges in the neo/adjuvant treatment setting. The recommendations were subsequently updated based on the most recent data emerging. A modified Delphi approach was used to develop this consensus. A consensus was achieved when ≥75% of voters selected an answer.

RESULTS AND CONCLUSIONS

The consensus recommendations addressed different escalation and de-escalation strategies in the setting of neoadjuvant therapy for early BC. The recommendations recapitulate the available clinical evidence and expert opinion to individualize patient management and optimize therapy outcomes. Consensus was reached in 63% of the statements (52/83), and the rationale behind each statement was clarified.

Stereotactic Radiosurgery with Volumetric Modulated Arc Radiotherapy: Final Results of a Multi-arm Phase I Trial (DESTROY-2)

AIMS

To present the final results of a phase I trial on stereotactic radiosurgery (SRS) delivered using volumetric modulated arc therapy (VMAT) in patients with primary or metastatic tumors in different extracranial sites.

MATERIALS AND METHODS

The DESTROY-2 trial, planned as a prospective dose escalation study in oligometastatic (one to five lesions) cancer patients relied on the delivery of a single high dose of radiation utilizing high-precision technology. The primary study endpoint was the definition of the maximum tolerated dose (MTD) of SRS-VMAT. The secondary objectives of the study were the evaluation of safety, efficacy, and long-term outcomes. All patients consecutively observed at our radiotherapy unit matching the inclusion criteria were enrolled. Each enrolled subject was included in a different phase I study arm, depending on the tumor site and the disease stage (lung, liver, bone, other), and sequentially assigned to a particular dose level.

RESULTS

Two hundred twenty seven lesions in 164 consecutive patients (male/female: 97/67, median age: 68 years; range: 29-92) were treated. The main primary tumors were: prostate cancer (60 patients), colorectal cancer (47 patients), and breast cancer (39 patients). The maximum planned dose level was achieved in all study arms, and the MTD was not exceeded. 34 Gy, 32 Gy, 24 Gy, and 24 Gy were established as the single-fraction doses for treating lung, liver, bone, and other extracranial lesions, respectively. The prescribed BED 2Gyα/β:10 to the planning target volume ranged from 26.4 Gy to 149.6 Gy. Twenty-seven patients (16.5%) experienced grade 1-2 and only one grade 3 acute toxicity, which was a pulmonary one. In terms of late toxicity, we registered only 5 toxicity>G2: a G3 gastro-intestinal one, three G3 bone toxicity, and a G3 laryngeal toxicity. The overall response was available for 199 lesions: 107 complete response (53.8%), 50 partial response (25.1%), and 31 stable disease (15.6%), leading to an overall response rate of 94.5%. Progression was registered only in 11 cases (5.5%). The overall response rate in each arm ranged from 88.6% to 96.4%. The overall two-year local control, distant metastasis free survival, disease free survival, and overall survival were 81.7%, 33.0%, 25.4%, and 78.7% respectively.

CONCLUSION

In conclusion, the planned doses of 34 Gy, 32 Gy, 24 Gy, and 24 Gy were successfully administered as single-fractions for the treatment of lung, liver, bone, and other extracranial lesions, respectively, in a prospective SRS dose-escalation trial. No dose-limiting toxicities were registered, and minimal acute and late toxicity were reported. New indications for SRS are currently being studied in oligoprogressive patients receiving targeted drugs or in combination with immunotherapy. The DESTROY-2 trial represents, in our opinion, a credible starting point for future modern radiosurgery trials.

Patterns of initial ovarian cancer recurrence on niraparib maintenance monotherapy in patients with no baseline evidence of disease after first-line chemotherapy: An ad hoc subgroup analysis of PRIMA/ENGOT-OV26/GOG-3012

OBJECTIVES

Patterns of disease recurrence on poly(ADP-ribose) polymerase inhibitor maintenance therapy are unclear and may affect subsequent treatment. This ad hoc subgroup analysis of the phase 3 PRIMA/ENGOT-OV26/GOG-3012 study evaluated patterns of initial recurrence in patients with advanced ovarian cancer (AOC).

METHODS

PRIMA included participants at high risk for disease progression. This ad hoc analysis only evaluated participants randomized to niraparib maintenance without evidence of disease at baseline. The number and site(s) of initial recurrent lesions at investigator-assessed progressive disease (PD) were evaluated.

RESULTS

Of the 314 niraparib-treated patients analyzed, 190 developed ≥1 new lesion (median number of new lesions, 1.0; interquartile range, 1-2). In total, 93.2% (177/190) of patients developed 1-3 lesions at first disease progression. The most common sites of recurrence were the peritoneum (30.0% [57/190]), lymph nodes (26.3% [50/190]), and liver (20.5% [39/190]). Similar results were observed when patients with PD were stratified by biomarker status, disease stage at diagnosis, and type of debulking surgery. Patients with homologous recombination-proficient tumors, stage III disease, or a history of primary debulking developed a median of 2.0 new lesions at first progression; patients with homologous recombination-deficient tumors, stage IV disease, or a history of interval debulking developed a median of 1.0 new lesion.

CONCLUSIONS

Many patients with AOC without lesions at first-line maintenance treatment initiation develop oligometastatic disease at first recurrence. Prospective evaluation is required to determine whether these patients have improved outcomes when local therapies are combined with continuous, systemic, targeted maintenance therapy.

Genomic signature for oligometastatic disease in non-small cell lung cancer patients with brain metastases

Purpose/objectives

Biomarkers for extracranial oligometastatic disease remain elusive and few studies have attempted to correlate genomic data to the presence of true oligometastatic disease.

Methods

Patients with non-small cell lung cancer (NSCLC) and brain metastases were identified in our departmental database. Electronic medical records were used to identify patients for whom liquid biopsy-based comprehensive genomic profiling (Guardant Health) was available. Extracranial oligometastatic disease was defined as patients having ≤5 non-brain metastases without diffuse involvement of a single organ. Widespread disease was any spread beyond oligometastatic. Fisher's exact tests were used to screen for mutations statistically associated (p<0.1) with either oligometastatic or widespread extracranial disease. A risk score for the likelihood of oligometastatic disease was generated and correlated to the likelihood of having oligometastatic disease vs widespread disease. For oligometastatic patients, a competing risk analysis was done to assess for cumulative incidence of oligometastatic progression. Cox regression was used to determine association between oligometastatic risk score and oligoprogression.

Results

130 patients met study criteria and were included in the analysis. 51 patients (39%) had extracranial oligometastatic disease. Genetic mutations included in the Guardant panel that were associated (p<0.1) with the presence of oligometastatic disease included ATM, JAK2, MAP2K2, and NTRK1, while ARID1A and CCNE1 were associated with widespread disease. Patients with a positive, neutral and negative risk score for oligometastatic disease had a 78%, 41% and 11.5% likelihood of having oligometastatic disease, respectively (p<0.0001). Overall survival for patients with positive, neutral and negative risk scores for oligometastatic disease was 86% vs 82% vs 64% at 6 months (p=0.2). Oligometastatic risk score was significantly associated with the likelihood of oligoprogression based on the Wald chi-square test. Patients with positive, neutral and negative risk scores for oligometastatic disease had a cumulative incidence of oligometastatic progression of 77% vs 35% vs 33% at 6 months (p=0.03).

Conclusions

Elucidation of a genomic signature for extracranial oligometastatic disease derived from non-invasive liquid biopsy appears feasible for NSCLC patients. Patients with this signature exhibited higher rates of early oligoprogression. External validation could lead to a biomarker that has the potential to direct local therapies in oligometastatic patients.

Focal therapy for oligometastatic and oligoprogressive renal cell carcinoma: a narrative review

Metastatic renal cell carcinoma (RCC) can present with oligometastatic disease and/or develop oligoprogression following systemic therapy. Cytoreductive and focal metastasis-directed therapy options include resection, stereotactic ablative radiation and thermal ablation. Aggressive focal therapy may allow delay in initiation of or modification to systemic therapy and improve clinical outcomes. In this narrative review we synthesize current practice guidelines and prospective data on focal therapy management options and highlight future research. Patient selection and the choice of focal treatment techniques are controversial due to limited and heterogeneous data and patients may benefit from multidisciplinary evaluation. Prospective comparative trials with clearly defined inclusion criteria and relevant end points are needed to clarify the risks and benefits of different approaches.

Immune checkpoint inhibitors rechallenge in non-small cell lung cancer: Current evidence and future directions

Immunotherapy, remarkably immune checkpoint inhibitors (ICIs), has significantly altered the treatment landscape for non-small cell lung cancer (NSCLC). Despite their success, the discontinuation of ICIs therapy may occur due to factors such as prior treatment completion, disease progression during ICIs treatment, or immune-related adverse events (irAEs). As numerous studies highlight the dynamic nature of immune responses and the sustained benefits of ICIs, ICIs rechallenge has become an attractive and feasible option. However, the decision-making process for ICIs rechallenge in clinical settings is complicated by numerous uncertainties. This review systematically analyses existing clinical research evidence, classifying ICIs rechallenge into distinct clinical scenarios, exploring methods to overcome ICIs resistance in rechallenge instances, and identifying biomarkers to select patients likely to benefit from rechallenge. By integrating recent studies and new technologies, we offer crucial recommendations for future clinical trial design and provide a practical guideline to maximize the therapeutic benefits of immunotherapy for NSCLC patients.

Stereotactic Body Radiation Therapy for Oligoprogressive Ovarian Cancer Patients Treated During Poly(ADP-Ribose)-Polymerase Inhibitor Maintenance: Efficacy and Adverse Events From the Epimetheo Retrospective Study

PURPOSE

The aim of this observational, retrospective, multicenter study (Epimetheo) was to analyze the activity and the safety of stereotactic body radiation therapy (SBRT) during poly(ADP-ribose)-polymerase inhibitor (PARPi) maintenance in a series of oligometastatic ovarian cancer (OC) patients.

METHODS AND MATERIALS

Patients treated with PARPi in maintenance setting received SBRT if oligometastatic progression occurred. Maintenance treatment was continued until the extensive progression of the disease. The primary endpoints of the study were as follows: next systemic treatment change-free survival (NEST-FS) and acute and late toxicity; the secondary endpoints were as follows: the rate of clinical complete response (CR), the 2-year actuarial local control (LC, progression of disease inside SBRT field) rate on "per lesion" basis, the 2-year actuarial progression-free survival, and 2-year overall survival (OS).

RESULTS

From April 2018 to September 2023, SBRT was used to treat 74 OC patients with a total of 158 lesions (98 lymph nodes and 60 parenchymal lesions) under PARPi maintenance. Olaparib, niraparib, and rucaparib were administered to 41.9%, 48.6%, and 9.5% of patients, respectively. CR, partial response, stable disease, and progressive disease were observed in 115 (72.8%), 32 (20.3%), 9 (5.7%), and 2 lesions (1.3%), respectively. Severe toxicities were reported in less than 3% of patients. The actuarial median NEST-FS was 10 months, with a range of 6.7-13.3 months. The 12- and 24-month actuarial NEST-FS rates were 44.9% and 31.4%, respectively. The 2-year actuarial LC, progression-free survival, and OS were 68.1%, 22.5%, and 77%, respectively with differences in figures between complete and incomplete responders. The achievement of CR was found to be correlated with an improvement in LC and OS.

CONCLUSIONS

This study reports the activity and the low toxicity profile of SBRT in association with PARPi in oligometastatic OC patients. A rapid, minimally invasive, and cost-effective treatment such as SBRT may be proposed as a means of prolonging NEST-FS and maintaining an effective treatment regimen involving PARPi.

Radiosurgery Society Case-Based Guide to Stereotactic Body Radiation Therapy for Challenging Cases of Spinal Metastases

PURPOSE

Spinal stereotactic body radiation therapy (SBRT) has become the standard of care in management of patients with limited sites of metastatic disease, radioresistant histologies, painful vertebral metastases with long life expectancy and cases of reirradiation. Our case-based guidelines aim to assist radiation oncologists in the appropriate utilization of SBRT for common, yet challenging, cases of spinal metastases.

METHODS AND MATERIALS

Cases were selected to include scenarios of large volume sacral disease with nerve entrapment, medically inoperable disease abutting the thecal sac, and local failure after prior SBRT. Relevant literature was reviewed, and areas requiring further investigation were discussed to offer a framework for evidence-based clinical practice.

RESULTS

Spinal SBRT can be effectively delivered in challenging cases following multidisciplinary discussion by using a methodical approach to patient selection, appropriate dose selection, and adherence to evidence-based dose constraints.

CONCLUSIONS

The Radiosurgery Society's case-based practice review offers guidance to practicing physicians treating technically challenging SBRT candidate patients with spinal metastases.

Coverage with evidence development program on stereotactic body radiotherapy in Belgium (2013-2019): a nationwide registry-based prospective study

Background

Although stereotactic body radiotherapy (SBRT) was progressively adopted in clinical practice in Belgium, a reimbursement request in 2011 was not granted because of remaining clinical and economic uncertainty. A coverage with evidence development (CED) program on SBRT started in 2013, with the aim to assess clinical and technical patterns-of-care in Belgium and monitor survival per indication, in view of supporting inclusion in the reimbursement system.

Methods

The Belgian National Institute for Health and Disability Insurance (NIHDI) initiated this prospective observational registry. Participating departments, using SBRT in clinical practice, signed the 'NIHDI convention'. Eligible patients had a primary tumour (PT) or oligometastatic disease (OMD). Patient, tumour, and treatment characteristics were collected through an online module of the Belgian Cancer Registry, prerequisite for financing. Five-year overall survival (5YOS) and 30- and 90-days mortality were primary outcomes, derived from vital status information.

Findings

Between 10/2013 and 12/2019, 20 of the 24 accredited radiotherapy departments participated, 6 were academic. Registered cases per department ranged from 21 to 867. Of 5675 registrations analysed, the majority had good performance status and limited number of lesions. Enrolment of PTs remained stable over time, OMDs almost doubled. Peripheral lung lesions dominated in PTs as in OMDs. Other metastases were (para)spinal, 'non-standard' and hepatic. Thirty- and 90-days mortalities remained below 0.5% [95% CI 0.3%-0.8%] respectively 2.1% [95% CI 1.6%-2.7%]. 5YOS varied by indication, primary prostate patients performing best (85%, 95% CI [76%, 96%]), those with liver metastases worst (19%, 95% CI [15%, 24%]). Better OS was observed in academic departments, department size did not significantly impact survival. OMD survival was better in 2018-19.

Interpretation

CED can be used to define patterns-of-care and real-life outcome of innovative radiotherapy. As the observed survival for different indications was in line with outcome in emerging literature, SBRT was included in the Belgian reimbursement system as of January 2020.

Funding

NIHDI financed participating departments per registered case.

The prognostic value of pretreatment 18F-FDG PET-CT parameters with peripheral blood markers in patients with de novo metastatic nasopharyngeal carcinoma

BACKGROUND AND PURPOSE

To develop and validate a prognostic nomogram based on pretreatment 18F-fluorodeoxyglucose positron emission tomography/computed tomography (PET-CT)radiomics parameters and peripheral blood markers for risk stratification in patients with de novo metastatic nasopharyngeal carcinoma (dmNPC).

MATERIALS AND METHODS

A total of 558 patients with dmNPC were retrospectively enrolled between 2011 and 2019. Eligible patients were randomly divided into training and validation cohorts (7:3 ratio). A Cox regression model was used to identify prognostic factors for overall survival (OS). The predictive accuracy and discriminative ability of the prognostic nomogram were determined using the concordance index (C-index) and calibration curve.

RESULTS

Independent factors derived from multivariable analysis of the training cohort to predict death were lactate dehydrogenase levels, pretreatment Epstein-Barr virus DNA, total lesion glycolysis of locoregional lesions, number of metastatic lesions, and age, all of which were assembled into a nomogram with (nomogram B) or without PET-CT parameters (nomogram A). The C-index of nomogram B for predicting death was 0.70, which was significantly higher than the C-index values for nomogram A. Patients were then stratified into low- and high-risk groups based on the scores calculated using nomogram B for OS. The median OS was significantly higher in the low-risk group than in the high-risk group (69.60 months [95 % CI: 58.50-108.66] vs. 21.40 months [95 % CI: 19.20-23.90]; p＜0.01). All the results were confirmed in the validation cohort.

CONCLUSION

The proposed nomogram including PET-CT parameters yielded accurate prognostic predictions for patients with dmNPC, enabling effective risk stratification for these patients.

Clinical management of oligometastatic cancer: Applying multidisciplinary tumor board recommendations in practice

Aims

Multidisciplinary tumor boards (MDTs) are an integral part of ensuring high-quality, evidence-based and personalized cancer care. In this study, we aimed to evaluate the adherence to and implementation of MDT recommendations in patients with oligometastatic disease (OMD).

Methods

We screened all oncologic positron emission tomography (PET) scans conducted at a single comprehensive cancer center in 2020. Patients were included if they had evidence of imaging-based OMD from a solid organ malignancy on the index scans, had their OMD case discussed at an MDT, and were treated and followed up at the same center. A switch away from the MDT-recommended treatment modalities was classified as a major deviation; non-MDT-mandated adjustments to a recommended treatment modality were coded as minor deviation. Clinical data was obtained via chart review; statistical calculations were computed using the R software.

Results

After review of PET and/or concurrent brain scans, 787 cases of OMD were identified. Thereof, 347 (44.1 %) cases were discussed at MDT, of which 331 (42.1 %) were therapeutically managed and subsequently followed. The three most commonly recommended therapies were systemic therapy (35.6 %), multimodality treatment including definitive local therapy (17.8 %), and radiotherapy (13.9 %). A major deviation was recorded in 16.3 % of cases (most commonly: none of the MDT-recommended treatment modalities were performed: 19 (35.2 %); not all MDT-planned treatment modalities were performed: 12 (22.2 %); and additional treatment modality was performed: 11 (20.3 %). A minor deviation was found in 1.5 % of cases. On multivariable regression, number of distant metastases (n > 1) was associated with a major deviation (OR: 1.85; 95 % CI, 1.0-3.52). Major deviations were associated with a significantly worse OS (p = 0.0034).

Conclusions

Adherence to and implementation of MDT recommendations in OMD patients was generally high (83.7%). Major deviations might be further reduced by more careful and elaborate discussions of OMD patient characteristics s and patient preferences.

Classification of Patients With Painful Tumors to Predict Response to Palliative Radiation Therapy

PURPOSE

This study aimed to identify factors affecting pain response to develop a patient classification system for palliative radiation therapy (RT).

METHODS AND MATERIALS

Our prospective observational study (UMIN000044984) provided data on patients who received palliative RT for painful tumors. The eligibility criteria were having a numerical rating scale (NRS) score of 2 or more before treatment and receiving palliative RT between August 2021 and September 2022. Post-RT follow-up was scheduled prospectively at 2, 4, 12, 24, 36, and 52 weeks. Pain response was assessed using the International Consensus Pain Response Endpoints criteria, with the primary outcome being the response rate within 12 weeks. Multivariable logistic regression was performed to identify factors affecting pain response and develop the classification system. Each class evaluated the differences in response rate, time to response, and progression.

RESULTS

Of the 488 registered lesions, 366 from 261 patients met the criteria. Most patients had bone metastases (75%), of whom 72% were using opioids and 22% underwent reirradiation. Conventional RT (eg, 8-Gy single fraction, 20 Gy in 5 fractions) was administered to 93% of patients. Over a median of 6.8 months of follow-up, the average NRS decreased from 6.1 to 3.4 at 12 weeks for 273 evaluable lesions, with a 60% response rate. Opioid use and reirradiation negatively affected the response rate in multivariate analysis (P < .01). Lesions were categorized into class 1 (no opioid use and no reirradiation; 89 lesions), class 2 (neither class 1 nor 3; 211 lesions), and class 3 (opioid use and reirradiation; 66 lesions), with respective response rates of 75%, 61%, and 36% (P < .001). Time to response was similar across the classes (P = .91), but the progression rates at 24 weeks differed (11%, 27%, and 63%, respectively; P < .001).

CONCLUSIONS

Opioid use and reirradiation are factors leading to significant variations in pain response rates and time to progression.

Treatment Classification by Intent in Oncology-The Need for Meaningful Definitions: Curative, Palliative and Potentially Life-Prolonging

BACKGROUND

Realistic cancer treatment goals should be used by health care professionals and communicated to patients, families, and the public. The current nomenclature on this subject is outdated and has not been changed since the advent of modern oncology in the middle of the 20th century.

METHODS

Based on the literature we propose a three-tier system composed of curative, palliative, and potentially life-prolonging (PLP) therapies, instead of the current two-tier system of only curative and palliative treatment.

RESULTS

The new system introduces the notion of prolonged survival. Furthermore, the negative connotation linked to palliative care is also eliminated in this setting.

CONCLUSION

The current terminology used to describe cancer treatment goals has not been updated since the mid-20th century and it is time for a more modern approach. We propose a three-tier system: (1) curative treatment, (2) palliative care, and (3) potentially life-prolonging therapy.

Palliative Thoracic Radiotherapy in the Era of Modern Cancer Care for NSCLC

Palliative thoracic radiotherapy provides rapid and effective symptom relief in approximately two-thirds of NSCLC patients treated. In patients with poor performance status, the degree of palliation appears unrelated to the radiation dose or fractionation schedule. Conversely, in patients with good performance status, higher radiation doses administered over longer periods have shown modest survival benefits. These findings stem from studies conducted before the advent of immunotherapy and targeted therapy in clinical practice. Currently, there are no large prospective studies specifically dedicated to palliative radiotherapy conducted in this new treatment era. Modern radiotherapy technologies are now widely available and are increasingly used for palliative purposes in selected patients, reflecting the expanded array of therapeutic options for disseminated NSCLC and improved prognosis. Some traditional tenets of palliative thoracic radiotherapy, such as the improvement of overall survival with a protracted radiation schedule and the use of simple, cost-effective radiation techniques for palliative purposes, may no longer hold true for patients receiving immunotherapy or targeted therapy. The application of IMRT or SBRT in the context of palliative radiotherapy for NSCLC is not yet sufficiently explored, and this is addressed in this review. Moreover, new risks associated with combining palliative radiotherapy with these systemic treatments are being explored and are discussed within the context of palliative care. The optimal timing, doses, fractionation schedules, and treatment volumes for radiotherapy combined with immunotherapy or targeted therapy are currently subjects of investigation. In emergencies, radiotherapy should be used as a life-saving measure without delay. However, for other indications of palliative thoracic radiotherapy, decisions regarding doses, timing relative to systemic treatments, and treatment volumes should be made in a multidisciplinary context, considering the patient's prognosis, anticipated outcomes, and access to potentially effective treatments. We still lack robust data from prospective studies on this matter. This review examines and discusses available evidence on the use of palliative thoracic radiotherapy within the framework of modern treatment strategies for NSCLC.

Optimal therapeutic strategies for hepatic metachronous oligometastatic nasopharyngeal carcinoma: Insights from a retrospective study

Hepatic metachronous oligometastatic nasopharyngeal carcinoma (hmoNPC) exhibits distinct clinical characteristics compared to other types of metastatic NPC. We investigated the optimal therapy for hmoNPC. 160 patients with hmoNPC treated in Sun Yat-sen University Cancer Center between 2010 and 2021 were retrospectively recruited. A total of 56 patients were classified into the local therapy (LT) cohort, 23 into the systemic therapy (ST) cohort and 81 into the combination therapy (LT + ST) cohort. The median PFS was 7.9 months (95% confidence interval [CI]: 4.1-11.9 months) in the LT cohort, 15.5 months (95% CI: 10.5-32.3 months) in the ST cohort, and 31.3 months (95% CI: 20.3 to NA months) in the LT + ST cohort. The median OS was 41.1 months (95% CI: 30.0-54.0 months) in the LT cohort, 50.4 months (95% CI: 41.5 to NA months) in the ST cohort and not reached (NR) (95% CI: 77.3 to NA months) in the LT + ST cohort. Cox analysis was used to construct nomograms to predict patient outcomes. Among patients with no evidence of disease status after LT, the prognosis was significantly better in the LT + ST cohort than LT cohort (median PFS: NR [95% CI: 29.0 to NA months] vs. 20.0 months [95% CI: 10.4 to NA months]). More survival benefits were achieved with platinum-based chemotherapy than oral monotherapy (median PFS: NR [95% CI: 21.7 to NA months] vs. 17.2 months [95% CI: 10.2 to NA months]). Fewer postoperative early progression events were observed in neoadjuvant chemotherapy cohort than in adjuvant chemotherapy cohort (2.78% vs. 18.81%, P = .013). In conclusion, combining neoadjuvant platinum-based chemotherapy and local therapy was the best strategy for patients with hmoNPC.

PSMA-PET/CT response after metastasis-directed radiotherapy of bone oligometastases in prostate cancer

OBJECTIVE

Bone metastases are very common in advanced prostate cancer and can sensitively be detected utilizing PSMA-PET/CT. Therefore, our goal was to evaluate the suitability of PSMA-PET/CT-guided metastasis-directed external beam radiotherapy (MDT) as treatment option for patients with biochemical recurrence and oligometastatic bone lesions.

MATERIALS & METHODS

We retrospectively examined 32 prostate cancer patients with biochemical recurrence and PSMA-positive oligometastatic disease limited to the bone (n = 1-3). A total of 49 bone lesions were treated with MDT. All patients received a post-radiotherapy PSMA-PET/CT-Scan. Changes in SUVmax, PSMA-positive tumor volume per lesion and PSA, as well as the correlation between the PET/CT-interval and SUVmax response were calculated.

RESULTS

MDT lead to a SUVmax decrease in 46/49 (94%) of the lesions. The median relative decline of SUVmax was 60.4%, respectively. Based on PSMA-positive lesion volume with a SUV cut-off of 4, 46/49 (94%) of lesions showed complete response, two (4%) partial response and one lesion (2%) was stable on PSMA-PET/CT after MDT. Most of the treated patients (56.3%) showed an initial PSA decline at three months and a PSA nadir of median 0.14 ng/ml after a median time of 3.6 months after MDT. The median relative PSA change at three months after MDT was 3.9%.

CONCLUSION

MDT is a very effective treatment modality for prostate cancer bone oligometastases and lesion response to MDT can be assessed using the (semi-)quantitative parameters SUVmax and PSMA-positive lesion volume with established SUV cut-offs.

Liver Oligometastasis in Biliary Tract Cancer and Impact on Survival Outcomes

PURPOSE

Outcomes of unresectable biliary tract cancer (BTC) with varying extents of liver involvement remain unclear. We evaluated characteristics and outcomes of BTC patients with liver metastases who underwent chemotherapy.

METHODS

We retrospectively reviewed consecutive BTC patients with synchronous or metachronous intrahepatic metastases who started first-line chemotherapy at our institution between January 2016 and December 2021.

RESULTS

Ninety-six patients were included, of which 57 only had liver metastases and 39 had multiorgan involvement. The liver only group had longer median overall survival (OS) (11.8 vs. 7.4 months, P = 0.006) and median progression-free survival (PFS) (4.1 vs. 2.7 months, P = 0.035) than the multiorgan group. Patients with oligometastases (defined as no more than three liver metastases) achieved longer OS than those with polymetastases (four or more liver metastases) in the entire cohort. Within the liver only group, there were no significant differences in OS or PFS between the oligometastasis and polymetastasis groups. Patients who underwent subsequent surgery had significantly longer median OS than those who did not (44.4 vs. 7.7 months, P < 0.001). Age ≥ 75 years, liver-only metastasis, modified Glasgow prognostic score ≥ 1 carcinoembryonic antigen ≥ 5 μg/L, and subsequent surgery were independent predictors of OS. Liver oligometastasis was only a significant predictor of longer OS in univariate Cox analysis.

CONCLUSIONS

Outcomes in BTC patients with metastases limited to the liver, particularly those with oligometastasis, were more favorable than those with multiorgan metastases. Selected cases, generally with liver oligometastases, may achieve prolonged OS through subsequent surgery.

Is Local Ablative Stereotactic Radiation Therapy a Valuable Rescue Strategy for Time on Drug in Patients Enrolled in Phase I Trials?

PURPOSE

Patients with advanced tumors enrolled in phase I trials display strong treatment expectations and few therapeutic alternatives. When oligoacquired resistance (OAR; ≤3 lesions of disease progression) occurs, local ablative stereotactic radiation therapy (SRT) could allow disease control and continuing the experimental systemic treatment.

METHODS AND MATERIALS

Data from patients enrolled in phase I trials evaluating systemic treatments, who experienced OAR while on the phase I systemic therapy and subsequently received SRT between January 2014 and April 2023, were retrospectively analyzed. Progression-free survival (PFS)1 (trial entry to OAR), PFS2 (SRT to first subsequent relapse), time to next systemic treatment (TTNT), and overall survival (OS) were assessed. First subsequent patterns of relapse after SRT were distinguished as OAR2, which could be locally rechallenged, or systemic acquired resistance (SAR; >3 lesions of disease progression). When available, correlations between molecular profile and pathway enrichments of OAR and SAR were explored.

RESULTS

Forty-two patients with 52 oligoprogressive lesions were analyzed. The median follow-up was 24 months. SRT allowed a median PFS2 of 7.1 months and a median TTNT of 12.8 months. PFS2 included 49% OAR2 and 51% SAR. Median time to first subsequent relapse (9.6 vs 3.5 months; P = .014) and TTNT (22.4 vs 7.6 months; P < .001) were longer for OAR2 compared with that for SAR. No severe toxicities were reported. A PFS1 of <6 months and de novo oligoprogressive lesions were associated with the presence of SAR. More diverse enriched gene pathways were observed for SAR compared with that for OAR2.

CONCLUSIONS

In patients enrolled in phase I trials, OAR managed with SRT may increase time on investigational systemic treatments. Predictive factors reflecting tumor aggressiveness and clonal heterogeneity could help deciphering OAR2 from SAR and maximize SRT output in the oligoprogressive setting.

Outcomes Analysis of Patients Receiving Local Ablative Therapy for Oligoprogressive Metastatic NSCLC Under First-Line Immunotherapy

CONTEXT

Nonsmall Cell Lung Cancer (NSCLC) treatment relies on first-line immunotherapy as single agent or combined with chemotherapy. Oligoprogression may be observed in this setting.

MATERIAL AND METHOD

We performed a European multicentric retrospective study on patients treated with first-line immunotherapy, who presented with oligoprogressive disease, treated with a local ablative treatment.

RESULTS

A total of 61 patients were retrospectively included between 2018 and 2022. Twenty-four patients (39%) received immunotherapy as single agent, and 37 (61%) chemo-immunotherapy. First oligoprogression occurred more frequently in pre-existing metastatic sites (47% of patients). Median PFS1 (defined as time to first oligoprogression) was 11.5 months [IC95%: 10.0-12.3]. We observed that 37 patients (61%) progressed after first oligoprogression, and 20 (54%) from them presented second oligoprogression. Median OS for the whole cohort was 72.0 months [IC95%: 19.3-124.8], with positive correlation between OS and PFS1 (R=0.65, P < .0001). After loco-ablative treatment with radiotherapy, disease control rate was 89% with ablative radiotherapy: 88% with conventional radiotherapy, and 89% with stereotactic radiotherapy.

CONCLUSION

Patients with oligoprogression under/after immunotherapy have better prognosis with a high risk of subsequent oligoprogression.

Addition of Metastasis-Directed Therapy to Systemic Therapy for Oligometastatic Pancreatic Ductal Adenocarcinoma (EXTEND): A Multicenter, Randomized Phase II Trial

PURPOSE

The EXTEND trial tested the hypothesis that adding comprehensive metastasis-directed therapy (MDT) to chemotherapy would improve progression-free survival (PFS) over chemotherapy alone among patients with oligometastatic pancreatic ductal adenocarcinoma (PDAC).

METHODS

EXTEND (ClinicalTrials.gov identifier: NCT03599765) is a multicenter, phase II basket trial randomly assigning patients with ≤five metastases 1:1 to MDT plus systemic therapy versus systemic therapy. Disease progression was defined by radiologic criteria (RECIST v1.1), clinical progression, or death. The primary end point was PFS in the per-protocol population, evaluated after all patients achieved at least 6 months of follow-up. Exploratory end points included systemic immune response measures.

RESULTS

Between March 19, 2019, and February 13, 2023, 41 patients were randomly assigned and 40 were eligible for the primary analysis of PFS (19 patients in the MDT arm; 21 patients in the control arm). At a median follow-up time of 17 months, the median PFS time was 10.3 months (95% CI, 4.6 to 14.0) in the MDT arm versus 2.5 months (95% CI, 1.7 to 5.1) in the control arm. PFS was significantly improved by the addition of MDT to systemic therapy (P = .030 for stratified log-rank test) with a hazard ratio of 0.43 (95% CI, 0.20 to 0.94). No grade ≥3 or greater adverse events related to MDT were observed. Systemic immune activation events were associated with MDT and correlated with improved PFS.

CONCLUSION

This study supports the addition of MDT to systemic therapy for patients with oligometastatic PDAC. Induction of systemic immunity is a possible mechanism of benefit. These results warrant confirmatory trials to refine treatment strategy and provide external validation.

Longitudinal cell-free DNA characterization by low-coverage whole-genome sequencing in patients undergoing high-dose radiotherapy

BACKGROUND AND PURPOSE

Current radiotherapy guidelines rely heavily on imaging-based monitoring. Liquid biopsy monitoring promises to complement imaging by providing frequent systemic information about the tumor. In particular, cell-free DNA (cfDNA) sequencing offers a tumor-agnostic approach, which lends itself to monitoring heterogeneous cohorts of cancer patients.

METHODS

We collected plasma cfDNA from oligometastatic patients (OMD) and head-and-neck cancer patients (SCCHN) at six time points before, during, and after radiotherapy, and compared them to the plasma samples of healthy and polymetastatic volunteers. We performed low-pass (on average 7x) whole-genome sequencing on 93 plasma cfDNA samples and correlated copy number alterations and fragment length distributions to clinical and imaging findings.

RESULTS

We observed copy number alterations in 4/7 polymetastatic cancer patients, 1/7 OMD and 1/7 SCCHN patients, these patients' imaging showed progression following radiotherapy. Using unsupervised learning, we identified cancer-specific fragment length features that showed a strong correlation with copy number-based tumor fraction estimates. In 4/4 HPV-positive SCCHN patient samples, we detected viral DNA that enabled the monitoring of very low tumor fraction samples.

CONCLUSIONS

Our results indicate that an elevated tumor fraction is associated with tumor aggressiveness and systemic tumor spread. This information may be used to adapt treatment strategies. Further, we show that by detecting specific sequences such as viral DNA, the sensitivity of detecting cancer from cell-free DNA sequencing data can be greatly increased.

Ablative Radiation Therapy to Restrain Everything Safely Treatable (ARREST): A Phase 1 Study of Stereotactic Ablative Radiation Therapy for Polymetastatic Disease

PURPOSE

This phase 1 study aimed to assess the safety and feasibility of SABR therapy delivery to all sites of polymetastatic disease (>10 metastases).

METHODS AND MATERIALS

A 3 + 3 study design was used with 5 dose levels from 6 Gy (6 Gy × 1) to 30 Gy (6 Gy weekly × 5). Dose-limiting toxicity (DLT) was defined as any grade 4 or 5 toxicity or more than 3 grade 3 toxicities within 6 weeks of treatment. The primary endpoint was the maximal tolerated dose, defined as the dose level where ≥2/6 of patients experienced DLT. Secondary endpoints included quality of life (Functional Assessment of Cancer Therapy - General and European Quality of Life 5 Dimension 5 Level) at 6 weeks posttreatment, progression-free survival, and overall survival.

RESULTS

Thirteen patients were accrued: 12 Gy (n = 3), 18 Gy (n = 3), 24 Gy (n = 4), and 30 Gy (n = 3), and 207 lesions were treated. Nine patients (69%) had acute toxicity: grade 1 (n = 6, 46%), grade 2 (n = 2, 15%; n = 1 pneumonitis and n = 1 fatigue), and grade 3 (n = 1, 7.7% neutropenia). There were no grade 4 or 5 toxicities. Mean ± SD quality of life (Functional Assessment of Cancer Therapy - General and European Quality of Life 5 Dimension 5 Level health state) was 80.4 ± 21.9 and 77.4 ± 20.9 at baseline versus 76.4 ± 21.8 and 68.0 ± 24.2 at 6-week follow-up, respectively (p = .009 and p = .055, respectively). With a median follow-up of 8.7 months posttreatment (IQR, 2.4-24 months), 8 of 13 patients had disease progression (62%). The median and 12-month progression-free survival were 3.6 months and 11.3%, respectively. The median and 12-month overall survival were 13.8 months and 62%, respectively.

CONCLUSIONS

In this phase 1 trial, SABR therapy for polymetastatic disease was technically feasible with acceptable acute toxicity at dose levels up to 30 Gy (6 Gy weekly × 5). DLT was not observed.

Outcomes of De Novo Oligometastatic Breast Cancer Treated With Surgery of Primary and Metastasis Directed Radiotherapy

OBJECTIVES

With sensitive imaging for breast cancer, the question arises whether present-day oncologists treat dOMBC with palliative systemic therapy (ST), which, a few years earlier, would have been treated with curative intent. We retrospectively analyzed outcomes of dOMBC treated with curative intent using a combination of surgery, metastasis-directed radiotherapy (RT), and adjuvant/neoadjuvant ST and have also explored the possible role of total lesional glycolysis of metastases and p53 immunohistochemistry in predicting outcomes.

METHODS

Data were collected from a prospectively maintained database using electronic medical records and Radiation Oncology Information System. In the study, dOMBC was defined as up to 3 metastatic sites, all amenable to treatment with ablative RT and primary and axillary disease amenable to curative surgery. Patients were treated with surgery, ST, and RT.

RESULTS

Patients underwent either breast conservation surgery or modified radical mastectomy. Patients were treated with 6 to 8 cycles of chemotherapy in the neoadjuvant and/or adjuvant setting. Hormone receptor-positive patients received either tamoxifen or aromatase inhibitors. Trastuzumab was offered to Her-2-neu receptor-positive patients. RT included locoregional RT and metastases-directed ablative body RT. The median progression-free survival was 39 months (95% CI: -28.7 to 50.1 mo). Two and 3 year estimated disease-free survival (DFS) was 79% and 60.5%, respectively. The median overall survival was not reached. The estimated 3-year overall survival was 87.3%. Total lesional glycolysis of metastases score and p53 status did not affect DFS.

CONCLUSION

Combination treatment of surgery, metastases-directed ablative RT, and ST may provide prolonged DFS in dOMBC.

A real-world analysis of stereotactic body radiotherapy combined with immunotherapy in advanced or recurrent non-small cell lung cancer (NSCLC): A single-center experience

Background

We aimed to assess the value of stereotactic body radiotherapy (SBRT) delivered under the situation of controlled or progressed disease during ICI therapy in advanced or recurrent NSCLC.

Methods

We retrospectively collected patients with advanced or recurrent NSCLC who received SBRT concurrently with ICI in our institution between January 2017 and December 2021. Patients were divided into two groups, including those for whom SBRT was delivered initially or to the residual tumors during the first- or later-line ICI treatment (Group 1), and those for whom SBRT was given to the progressed tumors irrespective of first- or later-line ICI treatment (Group 2).

Results

A total of 144 patients were included. With median follow-up duration of 25.6 (range: 3.6 to 56.2) months, median progression-free survival (PFS) was 13.7 (95 % CI: 10.4 to 17.1) months and median overall survival (OS) was 52.8 [95 % CI: 30.6 to not available (NA)] months. In Group 1 (n = 78), median PFS was 17.9 (95 % CI: 14.5 to 29.8) months while median OS was not reached and 5-year OS rate was 61.2 %. In Group 2 (n = 66), median PFS was 8.0 (95 % CI: 6.0 to 13.1) months and median OS was 30.6 (95 % CI: 21.5 to NA) months.

Conclusions

SBRT combined with ICI demonstrated favorable survival for advanced or recurrent NSCLC, delivered in a controlled-disease situation as well as to progressed diseases with salvage-intent. Future prospective studies are warranted to investigate the optimal SBRT dose regimen and appropriate combination strategy to synergize ICI.

Local Therapy for Metastatic Colorectal Cancer: A Case-Based Review

ABSTRACT

The oligometastatic disease state, defined as a cancer with 5 or fewer sites of metastasis, is a therapeutic opportunity to improve oncologic outcomes. Colorectal cancer (CRC) was among the first for which oligometastatic treatment was used in routine clinical practice, and recent studies have shown potential for improved overall survival with metastasis-directed therapies. As CRC is the third most common cause of cancer death in men and women, improving oncologic outcomes in this population is of paramount importance. The relatively recent identification of this treatment paradigm and paucity of high-quality data have led to heterogeneity in clinical practice. This review will explore perspectives of a panel of surgical and radiation oncologists for complex or controversial cases of metastatic CRC.

Pelvic lymph node motion during cone-beam computed tomography guided stereotactic radiotherapy

Background and purpose

Stereotactic body radiotherapy (SBRT) is increasingly applied for pelvic lymph node recurrence. Thus far, knowledge on pelvic lymph node motion during CBCT-guided SBRT is lacking and the applied margins vary between institutions. This study evaluated pelvic lymph node motion during CBCT-guided SBRT and assessed the currently applied PTV margins of 3 and 5 mm.

Material and methods

In total, 45 pelvic lymph node metastases were included. One observer delineated 45 GTVs on planning CT, 224 GTVs on pre-fraction and 216 on post-fraction CBCT. The GTV centroid coordinates were derived from all images for inter- and intrafraction motion analysis. Additionally, we assessed the influence of treatment time and lesion location on lesion motion. The expected coverage of a 3-mm and 5-mm PTV margin was assessed using the inclusiveness index for GTVs on pre- and post-fraction CBCT.

Results

Lymph node interfraction motion was limited to 5 mm in 96-97 % of fractions for all translational directions and intrafraction lesion motion was limited to 3 mm in 97-100 % of fractions. Para-rectal lesions (11 %) were associated with significantly larger inter- and intrafraction motion compared to other pelvic locations and treatment duration showed no correlation with lesion motion. The mean (sd) lesion inclusiveness index was 99 % (5 %) for the 5-mm PTV margin and 96 % (9 %) for the 3-mm margin.

Conclusion

Pelvic lymph node motion during CBCT-guided stereotactic radiotherapy was within the widely applied PTV margin of 5 mm, providing an opportunity to reduce this margin for pelvic lymph node SBRT.

Is there a role for metastasis-directed therapy in bladder cancer?

PURPOSE OF REVIEW

This article aims to comprehensively review and critique the existing literature on the role of metastatic-directed therapy in patients with metastatic bladder cancer, particularly in oligometastatic disease state.

RECENT FINDINGS

The role of metastasectomy in metastatic bladder cancer is still controversial. Several studies have demonstrated improved outcomes, particularly in a highly selected patients with small metastatic lesions or with lung or brain metastases, whereas others show no significant survival benefit. Combining metastasectomy with systemic therapies, such as immunotherapy and chemotherapy, has also shown benefits. Metastasis-directed radiotherapy is evolving as a potentially effective approach with minimal toxicity in achieving local control and improving survival, particularly in patients with oligometastatic disease. The evidence regarding the impact of several factors such as performance status, metastatic burden, and the presence of visceral metastases on outcomes is mixed. Concurrent treatment with systemic therapy may potentiate the effectiveness of metastasis-directed therapy.

SUMMARY

In patients with metastatic deposits amenable to surgical resection, metastasectomy stands as a promising avenue. Metastatic-directed radiotherapy has demonstrated local control and improved survival in the evolving landscape of oligometastatic bladder cancer management. Further, well designed multicenter prospective studies are needed to support these findings and better understand the synergy between radiotherapy and systemic treatments, especially immunotherapy.

The current landscape of stereotactic body radiation therapy for metastatic castration-resistant prostate cancer

BACKGROUND

The onset of castration-resistance is associated with dismal outcomes in patients with prostate cancer (PCa). Metastasis directed therapy has been investigated in multiple disease settings and may improve outcomes in selected patients. Our systematic review aims to summarize evidence with stereotactic body radiotherapy (SBRT) in castration-resistant prostate cancer (CRPC).

METHODS

The literature search was performed on March 2024, on Pubmed, using the keywords "SBRT" AND "CRPC", and "stereotactic ablative radiotherapy (SABR)" AND "CRPC". This search retrieved a total of 108 articles, 19 were included.

RESULTS

The literature is largely dominated by retrospective series. In men with metachronous oligoprogression, SBRT with androgen receptor pathway inhibitor significantly increased progression-free survival (PFS) including biochemical progression-free survival in a randomized phase II trial (hazard ratio of 0.35, p < 0.001). In patients continuing ADT, the bPFS ranged between 9.5 months to 17.9 months, and next systemic treatment-free survival (NEST-FS) reached up to 2 years. In men with induced oligoprogression, SBRT enabled NEST-FS up to 3 years. SBRT was well tolerated, with less than 5% grade 3 toxicity reported across studies.

CONCLUSION

In the population of patients with oligometastatic CRPC, SBRT enables long-term biochemical response and PFS. In the oligoprogressive setting, SBRT could be integrated to prolong the duration and efficacy of systemic therapies. Nevertheless, the level of evidence remains very low and inclusion within prospective trials remain the preferred option for this population of patients.

Stereotactic body radiation therapy is beneficial for a subgroup of patients with urothelial cancer and solitary metastatic disease: a single institution real-world experience

BACKGROUND

Standard treatment options for patients with metastatic urothelial cancer (mUC) include systemic platinum-based chemotherapy, immunotherapy, antibody-drug-conjugates, and targeted therapy. Oligometastatic disease (OMD) may be an intermediate state between localized and generalized cancer. The best treatment strategy for OMD and oligoprogressive (OPD) disease is poorly studied in mUC but local stereotactic body radiation therapy (SBRT) could be an option to avoid or delay systemic treatment. The aim of this study was to assess the efficacy and feasibility of SBRT given in a real-world patient population.

METHODS

All patients with mUC treated with SBRT at Karolinska University Hospital, Stockholm, Sweden between 2009 and 2022 were included in this study. Baseline clinical characteristics, treatment data, SBRT dosimetry data and treatment outcome were collected retrospectively. The study endpoints were local control rate (LCR), progression-free-survival (PFS), overall survival (OS) and feasibility of SBRT.

RESULTS

In total 39 patients were treated with SBRT. The median follow-up was 25.6 months. The LCR was 82%. PFS and OS were 4.1 and 26.2 months, respectively. Treatment was well tolerated; all patients but one (treatment related pain) completed the planned SBRT. Number of metastases irradiated with SBRT was significantly associated with outcome; patients with only one irradiated lesion had more favourable PFS compared to individuals with 2 or more metastases (HR 4.12, 95% CI: 1.81-9.38, p = 0.001). A subgroup of patients (15%) achieved a sustained long-term survival benefit and never required systemic treatments after SBRT.

CONCLUSIONS

SBRT was well tolerated and associated with high LCR. A subpopulation of patients with single metastatic lesion achieved long-term OS and never required subsequent systemic treatment after SBRT. Prospective randomized studies are warranted to discover treatment predictive biomarkers and to investigate the role of SBRT in oligometastatic UC.

Radiation Oncologists' Perspectives on Oligometastatic Prostate Cancer: A Survey from Korean Oligometastasis Working Group

BACKGROUND

Interest in the oligometastatic prostate cancer (OMPC) is increasing, and various clinical studies have reported the benefits of metastasis-directed radiation therapy (MDRT) in OMPC. However, the recognition regarding the adopted definitions, methodologies of assessment, and therapeutic approaches is diverse among radiation oncologists. This study aims to evaluate the level of agreement for issues in OMPC among radiation oncologists.

METHODS

We generated 15 key questions (KQs) for OMPC relevant to definition, diagnosis, local therapies, and endpoints. Additionally, three clinical scenarios representing synchronous metastatic prostate cancer (mPC) (case 1), metachronous mPC with visceral metastasis (case 2), and metachronous mPC with castration-resistance and history of polymetastasis (case 3) were developed. The 15 KQs were adapted according to each scenario and transformed into 23 questions with 6-9 per scenario. The survey was distributed to 80 radiation oncologists throughout the Republic of Korea. Answer options with 0.0-29.9%, 30-49.9%, 50-69.9%, 70-79.9%, 80-89.9%, and 90-100% agreements were considered as no, minimal, weak, moderate, strong, and near perfect agreement, respectively.

RESULTS

Forty-five candidates voluntarily participated in this study. Among 23 questions, near perfect (n = 4), strong (n = 3), or moderate (n = 2) agreements were shown in nine. For the case recognized as OMPC with agreements of 93% (case 1), near perfect agreements on the application of definitive radiation therapy (RT) for whole metastatic lesions were achieved. While ≥70% agreements regarding optimal dose-fractionation for metastasis-directed RT (MDRT) has not been achieved, stereotactic body RT (SBRT) is favored by clinicians with higher clinical volume.

CONCLUSION

For the case recognized as OMPC, near perfect agreement for the application of definitive RT for whole metastatic lesions was reached. SBRT was more favored as a MDRT by clinicians with a higher clinical volume.

Detecting Metastatic Patterns of Oligometastatic Breast Cancer: A Comparative Analysis of 18F-FDG PET/CT and Conventional CT Imaging

Metastasis-directed therapy has the potential to improve progression-free and overall survival in oligometastatic disease (OMD). For breast cancer, however, randomized trials have failed so far to confirm this finding. Because the concept of metastasis-directed therapy in OMD is highly dependent on the accuracy of the imaging modality, we aimed to assess the impact of 18F-FDG PET/CT on the definition of OMD in breast cancer patients. Methods: Eighty patients with a total of 150 18F-FDG PET/CT images (between October 2006 and January 2022) were enrolled in this retrospective study at the Technical University of Munich. The inclusion criteria were OMD, defined as 1-5 distant metastases, at the time of 18F-FDG PET/CT. For the current study, we systemically compared the metastatic pattern on 18F-FDG PET/CT with conventional CT. Results: At the time of 18F-FDG PET/CT, 21.3% of patients (n = 32) had a first-time diagnosis of metastatic disease, 40.7% (n = 61) had a previous history of OMD, and 38% (n = 57) had a previous history of polymetastatic disease. In 45.3% of cases, the imaging modality (18F-FDG PET/CT vs. conventional CT) had an impact on the assessment of whether OMD was present. An identical metastatic pattern was observed in only 32% of cases.18F-FDG PET/CT detected additional metastases in 33.3% of cases, mostly in the nonregional lymph node system. Conclusion: The use of 18F-FDG PET/CT had a substantial impact on the definition of OMD and detection of metastatic pattern in breast cancer. Our results emphasize the importance of establishing a standardized definition for imaging modalities in future trials and clinical practices related to metastasis-directed therapy in breast cancer patients.

First-Line Treatments and Management of Metastatic Renal Cell Carcinoma Patients: An Italian Interdisciplinary Uro-Oncologic Group Algorithm

The treatment landscape for metastatic renal cell carcinoma (mRCC) has undergone significant transformations in recent years. The introduction of novel combination therapies involving tyrosine kinase inhibitors (TKI) and immune checkpoint inhibitors has resulted in improved oncological outcomes compared to traditional TKI monotherapy. In this evolving paradigm, the pivotal role of the multidisciplinary tumor board is underscored, particularly in shaping the therapeutic trajectory for patients eligible for locoregional interventions like cytoreductive nephrectomy and metastasectomy. In cases where systemic treatment is deemed appropriate, the absence of direct comparisons among the various combination therapies complicates the selection of a first-line approach. The clinician is faced with the challenge of making decisions based on patient-specific factors such as performance status, risk classification according to the International Metastatic Renal Cell Carcinoma Database Consortium, comorbidities, and disease characteristics, including the number and location of metastases and tumor histology. Considering these concerns, we propose, as a member of a Tuscany Interdisciplinary Uro-Oncologic Group, an algorithm to streamline the decision-making process for mRCC patients, offering guidance to clinicians in their day-to-day clinical practice.

Surgery for Oligometastatic Pancreatic Cancer: Defining Biologic Resectability

Pancreatic ductal adenocarcinoma (PDAC) is most often metastatic at diagnosis. As systemic therapy continues to improve alongside advanced surgical techniques, the focus has shifted toward defining biologic, rather than technical, resectability. Several centers have reported metastasectomy for oligometastatic PDAC, yet the indications and potential benefits remain unclear. In this review, we attempt to define oligometastatic disease in PDAC and to explore the rationale for metastasectomy. We evaluate the existing evidence for metastasectomy in liver, peritoneum, and lung individually, assessing the safety and oncologic outcomes for each. Furthermore, we explore contemporary biomarkers of biological resectability in oligometastatic PDAC, including radiographic findings, biochemical markers (such as CA 19-9 and CEA), inflammatory markers (including neutrophil-to-lymphocyte ratio, C-reactive protein, and scoring indices), and liquid biopsy techniques. With careful consideration of existing data, we explore the concept of biologic resectability in guiding patient selection for metastasectomy in PDAC.

Radioresistant Pulmonary Oligometastatic and Oligoprogressive Lesions From Nonlung Primaries: Impact of Histology and Dose-Fractionation on Local Control After Radiation Therapy

Purpose

We investigated whether pulmonary metastases from historically considered radioresistant primaries would have inferior local control after radiation therapy than those from nonradioresistant nonlung primaries, and whether higher biologically effective dose assuming alpha/beta=10 (BED10) would be associated with superior local control.

Methods and Materials

We identified patients treated with radiation therapy for oligometastatic or oligoprogressive pulmonary disease to 1 to 5 lung metastases from nonlung primaries in 2013 to 2020 at a single health care system. Radioresistant primary cancers included colorectal carcinoma, endometrial carcinoma, renal cell carcinoma, melanoma, and sarcoma. Nonradioresistant primary cancers included breast, bladder, esophageal, pancreas, and head and neck carcinomas. The Kaplan-Meier estimator, log-rank test, and multivariable Cox proportional hazards regression were used to compare local recurrence-free survival (LRFS), new metastasis-free survival, progression-free survival, and overall survival.

Results

Among 114 patients, 73 had radioresistant primary cancers. The median total dose was 50 Gy (IQR, 50-54 Gy) and the median number of fractions was 5 (IQR, 3-5). Median follow-up time was 59.6 months. One of 41 (2.4%) patients with a nonradioresistant metastasis experienced local failure compared with 18 of 73 (24.7%) patients with radioresistant metastasis (log-rank P = .004). Among radioresistant metastases, 12 of 41 (29.2%) patients with colorectal carcinoma experienced local failure compared with 6 of 32 (18.8%) with other primaries (log-rank P = .018). BED10 ≥100 Gy was associated with decreased risk of local recurrence. On univariable analysis, BED10 ≥100 Gy (hazard ratio [HR], 0.263; 95% CI, 0.105-0.656; P = .004) was associated with higher LRFS, and colorectal primary (HR, 3.060; 95% CI, 1.204-7.777; P = .019) was associated with lower LRFS, though these were not statistically significant on multivariable analysis. Among colorectal primary patients, BED10 ≥100 Gy was associated with higher LRFS (HR, 0.266; 95% CI, 0.072-0.985; P = .047) on multivariable analysis.

Conclusions

Local control after radiation therapy was encouraging for pulmonary metastases from most nonlung primaries, even for many of those classically considered to be radioresistant. Those from colorectal primaries may benefit from testing additional strategies, such as resection or systemic treatment concurrent with radiation.

Management of Oligometastatic Colorectal Cancer

The management of oligometastatic colorectal cancer differs from the treatment of metastatic colorectal cancer, and it is essential that those who treat oligometastatic disease be familiar with the treatment options for these patients. Although definitive treatment is often surgical, there are situations where local therapies such as SBRT or ablative techniques may better serve the patient. Adjuvant therapy should be provided to all patients, and neoadjuvant chemotherapy should be considered as well. The role of immunotherapy is currently limited due to the lack of clinical trials in this area.

Cancer-specific dose and fractionation schedules in stereotactic body radiotherapy for oligometastatic disease: An interim analysis of the EORTC-ESTRO E2-RADIatE OligoCare study

BACKGROUND AND INTRODUCTION

Optimal dose and fractionation in stereotactic body radiotherapy (SBRT) for oligometastatic cancer patients remain unknown. In this interim analysis of OligoCare, we analyzed factors associated with SBRT dose and fractionation.

MATERIALS AND METHODS

Analysis was based on the first 1,099 registered patients. SBRT doses were converted to biological effective doses (BED) using α/β of 10 Gy for all primaries, and cancer-specific α/β of 10 Gy for non-small cell lung and colorectal cancer (NSCLC, CRC), 2.5 Gy for breast cancer (BC), or 1.5 Gy for prostate cancer (PC).

RESULTS

Of the interim analysis population of 1,099 patients, 999 (99.5 %) fulfilled inclusion criteria and received metastasis-directed SBRT for NSCLC (n = 195; 19.5 %), BC (n = 163; 16.3 %), CRC (n = 184; 18.4 %), or PC (n = 457; 47.5 %). Two thirds of patients were treated for single metastasis. Median number of fractions was 5 (IQR, 3-5) and median dose per fraction was 9.7 (IQR, 7.7-12.4) Gy. The most frequently treated sites were non-vertebral bone (22.8 %), lung (21.0 %), and distant lymph node metastases (19.0 %). On multivariate analysis, the dose varied significantly for primary cancer type (BC: 237.3 Gy BED, PC 300.6 Gy BED, and CRC 84.3 Gy BED), and metastatic sites, with higher doses for lung and liver lesions.

CONCLUSION

This real-world analysis suggests that SBRT doses are adjusted to the primary cancers and oligometastasis location. Future analysis will address safety and efficacy of this site- and disease-adapted SBRT fractionation approach (NCT03818503).

Consideration of Metastasis-Directed Therapy for Patients With Metastatic Colorectal Cancer: Expert Survey and Systematic Review

BACKGROUND

A survey of medical oncologists (MOs), radiation oncologists (ROs), and surgical oncologists (SOs) who are experts in the management of patients with metastatic colorectal cancer (mCRC) was conducted to identify factors used to consider metastasis-directed therapy (MDT).

MATERIALS AND METHODS

An online survey to assess clinical factors when weighing MDT in patients with mCRC was developed based on systematic review of the literature and integrated with clinical vignettes. Supporting evidence from the systematic review was included to aid in answering questions.

RESULTS

Among 75 experts on mCRC invited, 47 (response rate 62.7%) chose to participate including 16 MOs, 16 ROs, and 15 SOs. Most experts would not consider MDT in patients with 3 lesions in both the liver and lung regardless of distribution or timing of metastatic disease diagnosis (6 vs. 36 months after definitive treatment). Similarly, for patients with retroperitoneal lymph node and lung and liver involvement, most experts would not offer MDT regardless of timing of metastatic disease diagnosis. In general, SOs were willing to consider MDT in patients with more advanced disease, ROs were more willing to offer treatment regardless of metastatic site location, and MOs were the least likely to consider MDT.

CONCLUSIONS

Among experts caring for patients with mCRC, significant variation was noted among MOs, ROs, and SOs in the distribution and volume of metastatic disease for which MDT would be considered. This variability highlights differing opinions on management of these patients and underscores the need for well-designed prospective randomized trials to characterize the risks and potential benefits of MDT.

Assessing the effect of metastasis-directed therapy in oligometastatic disease using the restricted mean survival time

BACKGROUND

Metastasis-directed therapy (MDT) with stereotactic body radiotherapy (SBRT) is emerging as an effective therapeutic option for oligometastatic disease (OMD). However, a lack of phase III data, consensus guidelines, and toxicity concerns limit its widespread use. Randomized controlled trials (RCTs) routinely report hazard ratios (HRs) and medians that lack clear clinical and robust interpretation. Restricted-mean survival time (RMST) is the duration of time a patient is expected to survive over the follow-up period, providing a robust and interpretable alternative. We analyzed the efficacy of SBRT using RMST.

METHODS

All registered RCTs of ablative radiotherapy in OMD in ClinicalTrials.gov through 2022 were identified. Data were reconstructed from Kaplan-Meier curves, and the HRs and RMST differences were estimated for surrogate endpoints (SEs) and overall survival (OS).

RESULTS

Six studies comprising 426 patients met the inclusion criteria. The RMST differences for SEs ranged from 4.6 months in a study by Iyengar et al. to 11.1 months in SABR-COMET. The RMST differences for OS in SABR-COMET, Gomez et al., and SINDAS studies were 12.6, 15 and 7.9 months, respectively.

CONCLUSION

RMST demonstrates the efficacy of local treatment in OMD. Representing the expected survival time, this method effectively communicates outcomes to patients and clinicians.

European clinical practice guidelines for the definition, diagnosis, and treatment of oligometastatic esophagogastric cancer (OMEC-4)

INTRODUCTION

The OligoMetastatic Esophagogastric Cancer (OMEC) project aims to provide clinical practice guidelines for the definition, diagnosis, and treatment of esophagogastric oligometastatic disease (OMD).

METHODS

Guidelines were developed according to AGREE II and GRADE principles. Guidelines were based on a systematic review (OMEC-1), clinical case discussions (OMEC-2), and a Delphi consensus study (OMEC-3) by 49 European expert centers for esophagogastric cancer. OMEC identified patients for whom the term OMD is considered or could be considered. Disease-free interval (DFI) was defined as the time between primary tumor treatment and detection of OMD.

RESULTS

Moderate to high quality of evidence was found (i.e. 1 randomized and 4 non-randomized phase II trials) resulting in moderate recommendations. OMD is considered in esophagogastric cancer patients with 1 organ with ≤ 3 metastases or 1 involved extra-regional lymph node station. In addition, OMD continues to be considered in patients with OMD without progression in number of metastases after systemic therapy. 18F-FDG PET/CT imaging is recommended for baseline staging and for restaging after systemic therapy when local treatment is considered. For patients with synchronous OMD or metachronous OMD and a DFI ≤ 2 years, recommended treatment consists of systemic therapy followed by restaging to assess suitability for local treatment. For patients with metachronous OMD and DFI > 2 years, upfront local treatment is additionally recommended.

DISCUSSION

These multidisciplinary European clinical practice guidelines for the uniform definition, diagnosis and treatment of esophagogastric OMD can be used to standardize inclusion criteria in future clinical trials and to reduce variation in treatment.

Navigating Breast Cancer Oligometastasis and Oligoprogression: Current Landscape and Future Directions

PURPOSE

We examine the potential for curative approaches among metastatic breast cancer (MBC) patients by exploring the recent literature on local ablative therapies like surgery and stereotactic body radiation therapy (SBRT) in patients with oligometastatic (OM) breast cancer. We also cover therapies for MBC patients with oligoprogressive (OP) disease.

KEY FINDINGS

Surgery and SBRT have been studied for OM and OP breast cancer, mainly in retrospective or non-randomized trials. While many studies demonstrated favorable results, a cooperative study and single-institution trial found no support for surgery/SBRT in OM and OP cases, respectively.

CONCLUSION

While there is interest in applying local therapies to OM and OP breast cancer, the current randomized data does not back the routine use of surgery or SBRT, particularly when considering the potential for treatment-related toxicities. Future research should refine patient selection through advanced imaging and possibly explore these therapies specifically in patients with hormone receptor-positive or HER2-positive disease.

Robotic Stereotactic Body Radiation Therapy for Oligometastatic Liver Metastases: A Systematic Review of the Literature and Evidence Quality Assessment

INTRODUCTION

The role of stereotactic body radiation therapy (SBRT) as a locally effective therapeutic approach for liver oligometastases from tumors of various origin is well established. We investigated the role of robotic SBRT (rSBRT) treatment on oligometastatic patients with liver lesions.

MATERIAL AND METHODS

This review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. The PubMed and Scopus databases were accessed by two independent investigators concerning robotic rSBRT for liver metastases, up to 3 October 2023.

RESULTS

In total, 15 studies, including 646 patients with 847 lesions that underwent rSBRT, were included in our systematic review. Complete response (CR) after rSBRT was achieved in 40.5% (95% CI, 36.66-44.46%), partial response (PR) in 19.01% (95% CI, 16.07-22.33%), whereas stable disease (SD) was recorded in 14.38% (95% CI, 11.8-17.41%) and progressive disease (PD) in 13.22% (95% CI, 10.74-16.17%) of patients. Progression-free survival (PFS) rates at 12 and 24 months were estimated at 61.49% (95% CI, 57.01-65.78%) and 32.55% (95% CI, 28.47-36.92%), respectively, while the overall survival (OS) rates at 12 and 24 months were estimated at 58.59% (95% CI, 53.67-63.33%) and 44.19% (95% CI, 39.38-49.12%), respectively. Grade 1 toxicity was reported in 13.81% (95% CI, 11.01-17.18%), Grade 2 toxicity in 5.57% (95% CI, 3.82-8.01%), and Grade 3 toxicity in 2.27% (955 CI, 1.22-4.07%) of included patients.

CONCLUSIONS

rSBRT represents a promising method achieving local control with minimal toxicity in a significant proportion of patients. Further studies are needed to evaluate the role of rSBRT in the management of metastatic liver lesions.

Management of oligometastatic and oligoprogressive epidermal growth factor receptor mutated non-small cell lung cancer patients: state of the art of a combined approach

Recently, the development of targeted therapy approaches such as those based on tyrosine kinase inhibitor (TKI) greatly improved the clinical outcomes of patients affected by oncogene addicted advanced non-small cell lung cancer (NSCLC). Similarly, the improvement of radiation therapy techniques has permitted to deliver high radiation doses to a limited number of metastatic target lesions (oligopersistent or oligoprogressive), with limited high-dose normal tissue exposure that leads to low severe toxicity rates. The aim of this narrative review was to provide an overview of the currently established definition of oligometastatic and oligoprogressive disease, to define first line and subsequent lines targeted therapies and the role of consolidative non-invasive local ablative treatments (LATs) in these settings. The potential benefit of local treatment (LT) such as radiotherapy (RT) or surgery might be represented by an overall reduction of switching to subsequent systemic treatments lowering the risk of further systemic dissemination. Further randomized clinical trials will clarify the role of LT and their correct timing in relation to systemic targeted therapies.