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    Real-world evidence

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    Confirmatory

    MROQC ADT Practice Patterns

    ForHigh-risk M0/N0-1 prostate on definitive RT, GG4-5 predominant

    TL;DRGuideline-concordant ADT (≥18mo) recommended in 67.0% of high-risk pts on definitive RT; ARPI intensification just 23.2% of STAMPEDE-eligible.

    Why it mattersRadiation oncology

    The RT prescriber's read is the adoption gap, not a treatment effect: even in a quality consortium, only 67.0% of high-risk pts on definitive RT are recommended ≥18mo ADT, and just 23.2% of STAMPEDE-eligible get ARPI intensification. Facility-level variability persists on multivariable analysis (P<.0001), so where a man is treated, not only his risk, sets his ADT. Prompts an audit of your own duration and intensification practice.

    8 details
    Design

    Prospective practice-pattern study within the Michigan Radiation Oncology Quality Consortium (MROQC), a statewide RT registry. 553 pts across 26 centers, Jun 2020–Nov 2024. Facility modeled as a random intercept (mixed-effects).

    Population & inclusion

    Intact, high-risk M0/N0-1 prostate cancer on definitive RT. GG4-5 75.0%, PSA ≥20 40.0%, cN1 19.9%, cT3/4 13.3%. 27.9% met STAMPEDE M0 intensification criteria.

    Endpoints

    Primary: intended guideline-concordant ADT (≥18mo). Also assessed: ARPI adoption before vs after STAMPEDE M0 publication, facility-level variability, and multivariable predictors of concordance.

    Results

    91.3% recommended any ADT, 67.0% guideline-concordant. ARPI intensification among STAMPEDE-eligible rose 0% → 23.2% post-publication. Facility variability persisted on MVA (P<.0001).

    FactorOR (GC-ADT)95% CI
    cN12.941.44-5.99
    GG46.232.85-13.62
    GG59.454.46-20.06
    PSA ≥403.641.22-10.87
    vs leading data

    Benchmarks real practice against the 2022 AUA/ASTRO guideline (18-36mo ADT) and STAMPEDE M0 (ARPI for high-burden high-risk). Documents a persistent adoption gap, not a treatment effect.

    Applies to
    high-risk M0/N0-1 prostate treated with definitive RT within a quality consortium
    Does not represent low/intermediate-risk disease, national non-consortium practice, or delivered (vs intended) treatment.
    Limitations

    Captures intended ADT duration and recommendations, not delivered therapy or adherence. Single-state consortium limits generalizability, and there is no efficacy or outcome endpoint.

    Rationale

    Descriptive practice-pattern audit (no efficacy endpoint); reinforces AUA/ASTRO ADT guideline and STAMPEDE M0 as benchmark, documenting under-adoption rather than testing a new effect.

    Monday clinic

    In high-risk men (GG4-5, cN1, PSA ≥40, or ≥2 STAMPEDE factors) starting definitive RT, this supports benchmarking ADT to ≥18mo and weighing ARPI intensification when STAMPEDE-eligible; it does not extend to low/intermediate-risk disease or ADT-omission decisions.

    Open questions
    • Does intended guideline-concordant ADT translate to delivered treatment and adherence?
    • What interventions reduce facility-level variability in ADT recommendations?
    • Do Michigan consortium patterns generalize to national practice?
    📚 Sources · 📄 1 paper
    📄 PAPER Dykstra, Michael P.; Regan, Samuel N.; Yin, Huiying (Maggie) et al. · JCO Oncology Practice (2025-09)
    Androgen Deprivation Therapy Practice Patterns in High-Risk Prostate Cancer Treated With Definitive Radiotherapy: Prospective Results From a Statewide Quality Consortium
    doi
    Abstract
    PURPOSE The 2022 AUA/ASTRO guidelines recommend 18-36 months of androgen deprivation therapy (ADT) with definitive radiotherapy for localized, high-risk prostate cancer. The STAMPEDE M0 trial supports intensification with androgen receptor pathway inhibitors (ARPIs) for patients with ≥2 cT3/T4, Grade Group [GG] 4-5, prostate-specific antigen (PSA) ≥40 ng/mL, or cN1. Given advances in imaging, risk stratification, and treatment delivery, we characterized contemporary practice patterns using prospective data from the Michigan Radiation Oncology Quality Consortium (MROQC). METHODS Patients enrolled in MROQC with intact, high-risk M0/N0-1 prostate cancer were included. Clinical information, including intended ADT duration and ARPI use, was prospectively collected. The primary outcome was intended guideline-concordant ADT (GC-ADT, ≥18 months). Multivariable analyses (MVA) assessed associations between clinical factors and GC-ADT recommendations. We compared the adoption of ARPI with standard therapies before and after the publication of STAMPEDE M0. Facility-level variability was evaluated using a mixed-effects model, with the treatment site as a random intercept. RESULTS Between June 2020 and November 2024, 553 patients across 26 centers were included: cT3/4 (13.3%), cN1 (19.9%), GG 4-5 (75.0%), and PSA ≥20 ng/mL (40.0%). Overall, 91.3% were recommended ADT, with 67.0% being guideline-concordant. On MVA, GC-ADT was significantly associated with cN1 (odds ratio [OR], 2.94 [95% CI, 1.44 to 5.99]), GG (GG4 OR, 6.23 [95% CI, 2.85 to 13.62]; GG5 OR, 9.45 [95% CI, 4.46 to 20.06]), and PSA ≥40 (OR, 3.64 [95% CI, 1.22–10.87]). Facility-level variability persisted in the MVA ( P &lt; .0001). Among the 27.9% who met meeting STAMPEDE criteria, ARPI recommendations increased from 0% prepublication to 23.2% afterward. CONCLUSION Within a statewide quality consortium, guideline-concordant ADT recommendations occurred in two thirds of patients, with ARPI intensification in under 25% among STAMPEDE-eligible patients. These findings highlight the need for individualized ADT strategies and collaborative efforts to standardize high-quality care.

    Systemic Curative Real-world evidence Confirmatory ASCO Annual Meeting 2026

    Early signal

    COMPPARE

    ForDe novo localized prostate cancer, excl very-high-risk and metastatic

    TL;DRProton vs IMRT: no difference in bowel urgency (6% vs 5.7%), ≥G2 GI tox, or 3-yr biochemical control in localized prostate.

    Why it mattersRadiation oncology

    The RT read is that rectal spacer use, not proton vs photon, moved GI toxicity: 2-yr G2+ fell to ~4.4-4.7% with a spacer vs 7.2-8.7% without (p=0.009), similar across modalities. Protons showed no toxicity or 3-yr biochemical-control edge, arguing against the proton premium for localized disease.

    COMPPARE
    EndpointIMRTProtonP
    Bowel urgency (EPIC)6%5.7%0.28
    Bowel frequency (EPIC)4%3.5%0.43
    GI tox ≥G2 (CTCAE)5.6%5.2%0.60
    3-yr FFDP (PSA)97.9%98.0%0.90
    +1 more figure
    COMPPARE
    Group2-yr G2+ GI toxicity (95% CI)
    IMRT, no spacer7.2% (5.0%, 9.9%)
    Proton, no spacer8.7% (5.0%, 14%)
    IMRT, spacer4.4% (2.8%, 6.4%)
    Proton, spacer4.7% (3.6%, 6.0%)
    6 details 5 trials watching
    Design

    Prospective comparative effectiveness study (COMPPARE, PCORI-funded), non-randomized proton vs photon cohorts across 51 centers. 2524 accrued July 2018-October 2022. Early results, short follow-up.

    Population & inclusion

    De novo localized prostate cancer, excluding very-high-risk and metastatic. Proton cohort n=1500, photon (IMRT) cohort n=1000.

    Radiotherapy

    Proton therapy vs IMRT; rectal spacer use captured as a covariate (FDA-approved 2015). Dose/fractionation and target volume not reported in source.

    Endpoints

    Co-primary patient-reported bowel urgency and frequency (EPIC) and ≥G2 GI toxicity (CTCAE v5), each powered 90%. Exploratory: 3-yr freedom from PSA progression.

    Results

    No significant proton advantage on any endpoint (all p ≥ 0.28). Observed toxicity fell far below design assumptions (hypothesized IMRT GI tox 29%, actual 5.6%).

    Safety

    Rectal spacer reduced 2-yr cumulative G2+ GI toxicity in both arms (p=0.009); the spacer effect exceeded any proton-vs-IMRT difference.

    vs leading data

    Directionally consistent with PARTIQoL (randomized proton vs IMRT, localized prostate), which found no bowel-QoL advantage for protons.

    Applies to
    de novo localized prostate cancer treated with definitive protons or IMRT
    Does not represent very-high-risk or metastatic disease.
    Limitations

    Non-randomized cohorts (selection bias, residual confounding); short follow-up leaves late GU/GI toxicity and long-term control unanswered; dose/fractionation not reported.

    Rationale

    Prospective but non-randomized cohorts (selection bias); early results, short f/u leave late toxicity and long-term control open. Null aligns with randomized PARTIQoL non-superiority.

    Monday clinic

    In localized prostate cancer (de novo, excluding very-high-risk and metastatic), these early data question routine proton use over IMRT for GI toxicity or 3-yr control; they do not yet speak to late toxicity or long-term outcomes.

    Open questions
    📚 Sources · 🐦 1 tweet

    Radiation Curative Real-world evidence Early signal

    Caveats dominate

    OCEANUS

    ForAdvanced/refractory NSCLC on immunoradiotherapy, median age 64, 74% male

    TL;DRSequential iRT beat concurrent for real-world OS in newly-dx advanced NSCLC: median 20.3 vs 16.0 mo, HR 0.68 (0.47-0.99), P=.045.

    Why it mattersRadiation oncology

    Sequential iRT (ICI and RT not overlapping) beat concurrent for real-world OS in newly-dx advanced NSCLC, HR 0.68 (0.47-0.99), P=.045, favoring temporal separation of RT from ICI. RT dose, fractionation, and target volume aren't in the source, so the signal can't yet transfer to a specific plan. The refractory RT+ICI-maintenance read was NS (P=.20).

    7 details 1 trial watching
    Design

    Territory-wide real-world cohort (OCEANUS, Hong Kong CDARS, >90% population coverage); NSCLC diagnosed 2010-2021 who received iRT. Overlap-weighting propensity score primary, IPTW sensitivity; landmark-based OS with weighted Kaplan-Meier and Cox (restricted mean survival time where PH violated).

    Population & inclusion

    335 of 3522 ICI-treated pts received RT: 155 newly-dx advanced, 180 refractory. Median age 64 (34-90), 73.7% male. Refractory analysis required survival ≥90 days (landmark).

    Radiotherapy

    RT dose, fractionation, modality, and target volume not reported in source. The variable studied is timing of RT relative to ICI (sequential vs concurrent), not technique.

    Results

    Both comparisons favored the sequential / ICI-maintenance arm (magnitudes in table). Chemotherapy was associated with longer OS in newly-dx pts only; not significant in refractory disease.

    Setting / comparisonExperimental OSControl OSHR / P value
    Newly-dx advanced, sequential vs concurrent iRT20.3 mo (95% CI 13.3-NR)16.0 mo (95% CI 8.3-30.0)HR 0.68 (0.47-0.99), P=.045
    Refractory, RT + ICI maintenance vs RT alone11.2 mo (95% CI 7.9-20.6)6.7 mo (95% CI 4.4-17.4)P=.20 (ns)
    vs leading data

    Randomized data on iRT sequencing in advanced NSCLC are limited (stated by authors). RT-before-ICI direction is consistent with the PACIFIC consolidation paradigm, but PACIFIC treated curative-intent unresectable stage III with concurrent chemoRT, a different population.

    Applies to
    advanced or refractory NSCLC receiving immunoradiotherapy, predominantly male, median age 64
    Does not represent curative-intent stage III chemoRT, oligometastatic, or ICI-treated patients who did not receive RT.
    Limitations

    Observational: sequential vs concurrent not randomized, residual confounding by indication despite weighting. Small subgroups (155 newly-dx). Refractory comparison non-significant (P=.20).

    Rationale

    Observational real-world cohort; sequential-vs-concurrent not randomized, confounding by indication despite propensity weighting. Small subgroups (155 newly-dx). Authors label it hypothesis-generating.

    Monday clinic

    In newly-diagnosed advanced NSCLC starting immunoradiotherapy, this real-world signal supports separating RT from ICI in time rather than delivering them concurrently; it does not extend to refractory disease, where the RT-plus-ICI-maintenance benefit was not significant.

    Open questions
    📚 Sources · 📄 1 paper
    📄 PAPER Zhou; Wang; Lee et al. · JAMA oncology (2026-05)
    Combination of Radiotherapy and Immunotherapy in Advanced Non-Small Cell Lung Cancer.
    PMID 41885834 → doi full text (PMC)
    Abstract
    IMPORTANCE: The optimal sequencing of radiotherapy (RT) combined with immunotherapy (iRT) and the value of chemotherapy remain undefined for advanced non-small cell lung cancer (NSCLC), where randomized data are limited.<br/><br/>OBJECTIVE: To compare real-world overall survival (OS) between sequential and concurrent iRT in newly diagnosed advanced NSCLC, assess the effect of immune checkpoint inhibitor (ICI) maintenance after RT in refractory disease, and evaluate the association of chemotherapy with survival.<br/><br/>DESIGN, SETTING, AND PARTICIPANTS: This is a territory-wide study (OCEANUS) based on the Hong Kong Hospital Authority Clinical Data Analysis and Reporting System (more than 90% population coverage). Patients with NSCLC diagnosed from January 1, 2010, to December 31, 2021, who subsequently received iRT for advanced or refractory disease were included. Overlap weighting was the primary propensity score-weighted method, with inverse probability of treatment weighting used for sensitivity analysis. Data were analyzed from December 2024 to April 2025.<br/><br/>EXPOSURES: Sequential vs concurrent iRT for newly diagnosed advanced NSCLC; RT with vs without ICI maintenance for refractory NSCLC; receipt of chemotherapy.<br/><br/>MAIN OUTCOMES AND MEASURES: The primary outcome was real-world OS after landmark, estimated with weighted Kaplan-Meier and Cox models. When proportional hazards were violated (per Schoenfeld residuals), treatment effects were summarized using restricted mean survival time.<br/><br/>RESULTS: Of 3522 patients who received ICIs, 335 received RT, including 155 with newly diagnosed advanced and 180 with refractory NSCLC. Of these, 247 (73.7%) were male, and the median (range) age was 64 (34-90) years. In newly diagnosed NSCLC, patients treated with sequential iRT had significant longer real-world OS than those treated with concurrent iRT (median, 20.3 months [95% CI, 13.3 to not reached] vs 16.0 months [95% CI, 8.3-30.0]; adjusted hazard ratio, 0.68; 95% CI, 0.47-0.99; P&#x2009;=&#x2009;.045). Chemotherapy was also associated with longer survival in patients with newly diagnosed advanced NSCLC. In refractory NSCLC, RT with ICI maintenance was associated with a numerically longer median real-world OS (11.2 months [95% CI, 7.9-20.6] vs 6.7 months [95% CI, 4.4-17.4]; P&#x2009;=&#x2009;.20). Addition of chemotherapy was not significant for real-world OS. Inverse probability of treatment weighting analyses produced similar estimates.<br/><br/>CONCLUSIONS AND RELEVANCE: In this cohort study, sequential iRT was associated with longer survival than concurrent iRT in patients with newly diagnosed advanced NSCLC, and chemotherapy was associated with longer survival. In patients with refractory NSCLC who survived at least 90 days, RT with ICI maintenance resulted in nonsignificantly longer survival and an unclear association with chemotherapy. These findings are hypothesis generating and support prospective randomized studies to define optimal sequencing of iRT and use of systemic treatment partners.
    📝 https://jamanetwork.com/journals/jamaoncology/fullarticle/2847148?guestAccessKey=6284363c-f1dd-46da-aa0e-8528e5ecca06&utm_source=twitter&utm_medium=social_jamaonc&utm_term=20674463146&utm_campaign=article_alert&linkId=952727864

    Combined Palliative Real-world evidence Caveats dominate

    Confirmatory

    DBCG IMN2 NCT06549920

    ForNode-positive breast cancer, incl. 1-3 positive nodes; no neoadjuvant therapy

    Overall survival

    HR 0.85

    95% CI 0.76-0.94, p=0.0016; 15yr OS 65.0% vs 60.8%

    TL;DR15yr OS 65.0% vs 60.8% with IMNI, adjusted HR 0.85 (0.76-0.94); benefit persists under modern systemic therapy and 3D RT.

    Why it mattersRadiation oncology

    The 1-3 positive-node subgroup is the RT read: IMNI benefit held at the lowest nodal burden, no subgroup found for omission, moving elective IMN coverage where guidelines diverge. Reassuring on toxicity too: 15yr ischemic/valvular cardiac death 0.2% (right/IMNI) vs 0.7% (left) under 3D planning.

    8 details 4 trials watching
    Design

    Prospective nationwide population-based cohort, N=4541, 6 RT centres, treated 2007-14. IMNI assigned by tumour laterality: right-sided → IMNI, left-sided → no IMNI. Median follow-up 13.7 yr.

    Population & inclusion

    Node-positive breast cancer, including the 1-3 positive-node low-burden group. Excluded prior malignancy, bilateral cancer, neoadjuvant systemic therapy, pre-RT recurrence, non-standard RT.

    Regimen

    Modern systemic backbone: taxane chemotherapy, trastuzumab, aromatase inhibitors, the era hypothesized to shrink absolute IMNI gain.

    Radiotherapy

    3D-based RT. IMNI delivered to right-sided tumours only; laterality allocation balances cardiac dose. Dose/fractionation not reported in source.

    Endpoints

    Primary: overall survival. Secondary: breast cancer mortality, distant metastasis.

    Results

    IMNI improved all three endpoints (see table). Absolute 15yr OS gain 4.2% (65.0% vs 60.8%).

    EndpointAdjusted HR (95% CI)p
    Overall survival0.85 (0.76-0.94)0.0016
    Breast cancer mortality0.84 (0.74-0.95)0.0077
    Distant metastasis0.87 (0.78-0.98)0.026
    StudyDesignSignal
    DBCG IMN1 (2003-07)prospective cohort, n=3089+4.7% abs OS, f/u 14.8yr
    EBCTCG meta-analysisn=12,167+3% abs 15yr survival, regional node RT
    Korean KROG 06-083D-RT, modern systemicnegative for IMNI
    vs leading data

    Confirms DBCG IMN1 (+4.7% abs OS at 14.8 yr) and the EBCTCG meta-analysis (+3% abs 15yr survival, regional node RT); contradicts the negative Korean KROG 06-08 in the modern-therapy era.

    Applies to
    node-positive breast cancer, including 1-3 positive nodes, treated with upfront surgery and modern systemic therapy
    Does not represent neoadjuvant-treated patients, who were excluded.
    Limitations

    Non-randomized: IMNI assigned by tumour laterality rather than randomization, so residual confounding is possible despite balanced baseline characteristics.

    Rationale

    Large prospective laterality-allocated cohort, not randomized; confirms IMN1 + EBCTCG that IMNI benefit persists with modern systemic therapy. Non-random design caps it below practice-changing.

    Monday clinic

    In node-positive breast cancer treated with upfront surgery then modern systemic therapy, especially 1-3 positive nodes, this supports including internal mammary nodes in the RT target; it does not extend to neoadjuvant-treated pts, who were excluded.

    Open questions
    📚 Sources · 📄 1 paper
    📄 PAPER Anders W. Mølby Nielsen; Lise B. J. Thorsen; Demet Özcan et al. · The Lancet Regional Health - Europe (2025-02)
    Internal mammary node irradiation in 4541 node-positive breast cancer patients treated with newer systemic therapies and 3D-based radiotherapy (DBCG IMN2): a prospective, nationwide, population-based cohort study
    doi

    Radiation Curative Real-world evidence Confirmatory

    Caveats dominate

    Tumour bed boost after BCS + WBRT

    ForPost-BCS invasive breast cancer treated with WBRT, Dutch cohort 2012-2016

    TL;DR10-yr IBTR 1.2% no-boost vs 1.2% boost in 0-2 risk factors; boost omission viable in modern systemic era.

    Why it mattersRadiation oncology

    The boost arm carries HIGHER crude IBTR at every stratum (10-yr 3.3% vs 2.7% at ≥3 RF), which is confounding by indication, not harm, and it means these data cannot estimate boost efficacy at all. What they do support is a floor: with 0-2 risk factors, 10-yr IBTR is 1.2% either way, so the omission decision rests on that absolute rate.

    Tumour bed boost after BCS + WBRT
    Risk factorsN no boostN boost5-yr no boost5-yr boost10-yr no boost10-yr boost
    0-215,08513,8450.6%0.7%1.2%1.2%
    ≥ 31497331.3%2.9%2.7%3.3%
    Uncertain5929440.8%3.3%1.4%3.6%
    +2 more figures
    Study aim: 5- and 10-yr IBTR with/without boost. Assisi thresholds: <3% boost, <6% no boost.
    Study aim: 5- and 10-yr IBTR with/without boost. Assisi thresholds: <3% boost, <6% no boost.
    Tumour bed boost after BCS + WBRT
    9 details
    Design

    Dutch population-based cohort (DBRT / Netherlands Cancer Registry linkage) of breast-conserving treatment, 2012-2016. Non-randomised: boost use reflects clinician risk assessment, not allocation.

    Population & inclusion

    Breast conserving treatment with or without an RT boost. Strata by number of risk factors: 0-2 (15,085 no boost / 13,845 boost), ≥3 (149 / 733), uncertain (592 / 944).

    Radiotherapy

    Whole-breast RT with or without tumour bed boost. No dose, fractionation, boost technique, or target-volume detail reported in source.

    Endpoints

    Primary: ipsilateral breast tumour recurrence (IBTR), histologically confirmed via a pathology-report text/code algorithm. Cumulative incidence reported at 5 and 10 years by risk-factor count.

    Results

    Low IBTR across every subgroup. Only the ≥3 risk-factor boost group crossed an Assisi threshold at 10 years (3.3%, vs the <3% bar).

    vs leading data

    EORTC 22881-10882 anchored the ~50% relative IBTR reduction from boost. Absolute IBTR here is an order of magnitude below that trial's era, which is the authors' argument that a relative halving now buys little absolute benefit.

    Applies to
    pts having BCS + WBRT for invasive breast cancer with 0-2 of the five listed risk factors, treated in the modern systemic-therapy era
    Does not represent pts with ≥3 risk factors, DCIS-only, or anyone whose boost benefit would be estimated from these data, since allocation was not randomised.
    Limitations

    Confounding by indication is the dominant issue: higher-risk pts got the boost, so crude boost-arm rates run higher. The ≥3 RF no-boost cell is 149 pts. 10-yr estimates on a 2012-2016 cohort are projected, and IBTR ascertainment was algorithmic.

    Rationale

    Registry cohort with non-random boost allocation; confounding by indication and a 149-pt no-boost ≥3 RF stratum undercut the omission claim.

    Monday clinic

    In post-BCS pts with 0-2 of the listed risk factors receiving WBRT, this supports discussing boost omission on absolute-risk grounds; it does not inform pts with ≥3 risk factors, where the ≥3 RF no-boost stratum is only 149 pts.

    Open questions
    • Which ≥3 risk-factor subgroups actually gain from a boost
    • Does boost omission hold with longer observed follow-up
    • Boost value in pts with residual disease after neoadjuvant therapy
    📚 Sources · 🐦 1 tweet

    Radiation Curative Real-world evidence Caveats dominate ESTRO Congress 2026

    Confirmatory

    OligoCare

    ForOligometastatic solid tumors treated with SABR; prostate/NSCLC/CRC/breast…

    TL;DRReal-world SABR local in-field progression 5.0% at 1yr, 11.4% at 3yrs across 2447 pts / 3533 lesions; CRC worst.

    Why it mattersRadiation oncology

    The histology split is the actionable read: CRC 3yr in-field failure 19.6% vs prostate 8.1%, despite CRC receiving the highest median dose per fraction. That argues for dose escalation or a combination strategy in CRC mets specifically, and it puts minimum PTV dose (not prescription dose) on the plan-review checklist.

    OligoCare
    Primaryn1 year3 years
    Colorectal5189.3%19.6%
    Breast3784.1%11.3%
    NSCLC5306.0%9.8%
    Prostate10212.7%8.1%
    +2 more figures
    OligoCare
    57 institutions, 2447 eligible pts, 3533 lesions. Median age 69 (28-94), 69% male. Median f/u 31 mo.
    57 institutions, 2447 eligible pts, 3533 lesions. Median age 69 (28-94), 69% male. Median f/u 31 mo.
    10 details
    Design

    EORTC OligoCare prospective real-world registry of SABR for oligometastatic disease, 57 institutions, accrual July 2019 to July 2025. Interim analysis; median follow-up 31 months (minimum 6).

    Population & inclusion

    2447 eligible pts with 3533 lesions. Median age 69 (28-94), 69% male. Primary tumors: prostate 1021 (42%), NSCLC 530 (22%), colorectal 518 (21%), breast 378 (15%).

    Radiotherapy

    SABR to metastatic sites; lesion locations were lung 807 (23%), non-vertebral bone 869 (25%), non-regional lymph node 558 (16%), spine 515, liver 306 (9%), brain 231 (7%), other 247 (7%). Minimum PTV dose correlated with outcome and is named the most critical technical factor; prescription dose and fractionation not reported in source.

    Endpoints

    Local in-field progression reported as cumulative incidence. No primary endpoint stated in the source; no survival or systemic-progression endpoints given here.

    Results

    Local in-field progression 5.0% at 1 year and 11.4% (99% CI 10.0-12.9%) at 3 years, i.e. 88.6% local control at 3 years, 237 events among 2447 pts.

    Discussion

    Colorectal primaries failed most (19.6% at 3 years) despite the highest median dose per fraction, which the authors read as relative radioresistance rather than underdosing and a case for dose escalation or combination approaches. De novo oligometastatic disease outperformed repeat OMD, attributed to higher delivered dose.

    Applies to
    pts receiving SABR for oligometastatic disease from prostate, NSCLC, colorectal, or breast primaries across European practice
    Does not represent randomised comparison of SABR against systemic therapy alone, nor histologies outside the four dominant primaries.
    Limitations

    Registry design with no comparator arm and heterogeneous dose/fractionation across 57 centres; indication and selection bias are unaddressed in source. Safety and toxicity outcomes are not reported in the source content.

    Rationale

    Large prospective multi-site registry with explicit histology-stratified analyses, but non-randomised and no comparator; supports rather than tests current oligomet SABR practice.

    Monday clinic

    In a CRC oligomet being planned for SABR, this registry supports treating minimum PTV dose as the coverage constraint to scrutinize and sets a realistic ~1 in 5 three-year in-field failure expectation; it does not extend to unirradiated or non-oligometastatic disease.

    Open questions
    • Optimal dose escalation strategy for colorectal oligometastases
    • Minimum PTV dose threshold for durable local control
    • Whether repeat OMD failure reflects dose or biology
    📚 Sources · 🐦 1 tweet

    Radiation Real-world evidence Confirmatory ESTRO Congress 2026