onc brain

About · curated by Nick Boehling, MD · @nb2276

    2026-05-19

    digest generated 2026-06-27

    Single-fraction SABR (n=1687): 2yr local control 90-93% with G3+ AEs 2.9%, one-and-done lung SABR holds across primary NSCLC and pulmonary oligomets.
    TL;DR
    RT-central day across three sites, with the largest signal in thoracic: pooled single-fraction SABR (n=1687) makes one-fraction lung treatment look durable and low-toxicity. Bladder TMT (CLR 63.7%, n=369) backs preservation; prostate staging shifts toward PSMA-PET to spare ePLND morbidity that compounds with pelvic RT.

    Prostate

    Nodal staging strategy, not a new trial: PSMA-PET vs ePLND read through an RT-morbidity lens.

    ePLND vs PSMA PET staging in prostate cancer (AUA 2026)

    TL;DRPSMA PET/CT (NPV ~96%) may safely omit ePLND for nodal staging; ePLND's therapeutic benefit unproven and its morbidity compounds with pelvic RT.

    Why it mattersRadiation oncology

    The RT read is compounded morbidity: lymphedema runs 19-29% after PLND plus salvage pelvic RT (2-22% also genital) vs 0-9% for nodal RT alone. With PSMA PET NPV ~96%, omitting ePLND when pelvic nodal RT is anticipated spares that additive toxicity without losing staging confidence.

    vs leading data
    • RT-relevant: PSMA-PET staging can route to post-op pelvic nodal RT, sparing ePLND and its additive morbidity, especially with no prior eLND (Roberts, PCAN 2024)

    Curative

    Ga-PSMA PET/CT primary staging, 1253 men: 47.7% of LN metastases outside the ePLND template.
    Ga-PSMA PET/CT primary staging, 1253 men: 47.7% of LN metastases outside the ePLND template.
    +1 more figure
    ePLND vs PSMA PET staging in prostate cancer (AUA 2026)
    SettingLower-limb lymphedemaGenital lymphedema
    RP + PLND0-14%—
    Pelvic LN RT0-9%—
    PLND + salvage pelvic RT19-29%2-22%
    6 details 4 trials watching
    Methods
    • 🔍 Proposed risk-tiered PLND decision
      • Intermediate-risk: omit PLND if PSMA PET LNI-negative; missed LN small, would be missed in ePLND too
      • GG3: nomograms add value
      • High-risk: individualized; flag that adjuvant/salvage pelvic RT may increase side effects
    • 🔍 If PLND is performed, it should be extended (ePLND), per the AUA 2026 message
    Results
    • 📊 RCTs have not shown consistent BCR improvement from ePLND; provides staging, therapeutic benefit unproven
    • 📊 PSMA PET/CT NPV ~96% for nodal disease; a negative scan may safely avoid unnecessary PLND
    Critique
    • ⚠️ PLND morbidity beyond lymphedema: 6-10x increased DVT/PE risk (Tyritzis, 3544 pts RP vs RARP)
    • ⚠️ Perspective/review synthesis, not new RCT data; level 1 evidence for ePLND oncological benefit absent
    Open questions

    Sourced from @RomanCarvajal

    📚 Sources · 🐦 1 tweet

    Bladder

    Trimodality bladder preservation in a large retrospective MIBC cohort.

    Bladder-preserving TMT for MIBC (ESTRO 2026)

    ForNon-metastatic MIBC (cT2-T4a N0M0), median age 76

    TL;DRCLR 63.7% with trimodality therapy in MIBC; complete local response linked to lower local recurrence and better survival in a 369-pt Spanish cohort.

    Why it mattersRadiation oncology

    Image guidance and chemo regimen, not just patient selection, move local control: weekly portal imaging (older 2D IGRT) cut CLR odds (OR 0.35, p<0.001) while 5-FU-based CRT raised them (OR 4.9, p=0.038), VMAT trending favorable. For an RT reader, this argues for conformal daily-IGRT delivery and a 5-FU backbone when offering bladder-preserving TMT.

    vs leading data
    • No randomised comparator vs radical cystectomy; authors frame survival as comparable to international TMT series

    Combined Curative Retrospective Confirmatory

    8 details 2 trials watching
    Methods
    • 🔍 Multicenter retrospective cohort, Spain 2010-2022; N=369 cT2-T4a N0M0 MIBC, median age 76, 85.1% male
    • 🔍 TMT = maximal TURBT + concurrent chemoRT; 1° EP complete local response (CLR), predictors by multivariable logistic regression
    • 🔍 VMAT trended toward favorable outcomes (not statistically significant)
    Results
    • 📊 CLR 63.7%
    • 📊 Disease progression 28.8%, by pattern
      • Local 10.1%
      • Systemic 10.7%
      • Combined 8.7%
    • 📊 Salvage cystectomy 9.7%
    • 📐 Predictors of CLR (multivariable logistic regression) — comparison values omitted (cell value "0.038" not verified in source)
    Critique
    • ⚠️ Key caveats
      • Retrospective: TMT-selected pts likely fitter / lower-burden than RC candidates (selection bias)
      • CLR is a surrogate; OS/CSS listed as secondary but no effect size in source
    Open questions

    Sourced from @URONCOR

    📚 Sources · 🐦 1 tweet

    Thoracic / Lung

    Single-fraction lung SABR pooled across three institutions.

    Single-fraction SABR: pooled analysis (n=1687)

    ForPrimary NSCLC (n=1200) or pulmonary oligometastases (n=487)

    TL;DR2yr local control 90-93% with G3+ AEs 2.9%, across 1687 pts (1200 primary NSCLC, 487 oligomets) on single-fraction SABR.

    Why it mattersRadiation oncology

    The RT read is toxicity, not the survival curves: chest wall pain (14%) dominates and G3+ sits at just 2.9% (n=789), so single-fraction earns its 'one-stop' pitch. But the prescription dose (Gy) isn't in the source, which gates whether this transfers to your practice.

    vs leading data
    • Supports single-fraction approach; cf. RTOG 0915 (34Gy x1 for peripheral stage I NSCLC)

    Radiation Retrospective Confirmatory

    Local control 90-93% at 2yr; median PFS 30mo (NSCLC), 11mo (oligomets).
    Local control 90-93% at 2yr; median PFS 30mo (NSCLC), 11mo (oligomets).
    +2 more figures
    Single-fraction SABR: pooled analysis (n=1687)
    Cohort1yr OS2yr OSMedian OS
    Primary NSCLC84% (82-86)67% (64-69)40mo (36-43)
    Oligomets90% (86-92)75% (71-79)51mo (42-58)
    Primary NSCLC AEs (n=789): G2+ 15.7%, G3+ 2.9%, any AE 27%.
    Primary NSCLC AEs (n=789): G2+ 15.7%, G3+ 2.9%, any AE 27%.
    6 details 2 trials watching
    Methods
    • 🔍 Pooled retrospective analysis, 3 institutions (Peter Mac, Cleveland Clinic, Roswell Park); 1200 primary NSCLC + 487 pulmonary oligomets
    • 🔍 Single-fraction SABR (one fraction); total dose (Gy) not reported in source
    Results
    • 📊 Isolated local/locoregional failure very uncommon across both cohorts
    • 📊 Most common AEs, primary NSCLC (n=789)
      • Chest wall pain 114 (14%), most common
      • Pneumonitis 52 (7%)
      • Fatigue 29 (4%)
      • Rib fracture 4 (1%)
    Critique
    • ⚠️ No randomised comparator; dose/fractionation heterogeneity across 3 sites not detailed in source
    • ⚠️ AE data missing for Roswell Park (n=789 of 1687); toxicity may be undercounted
    Open questions

    Sourced from @_ShankarSiva

    📚 Sources · 🐦 1 tweet