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Consensus

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Consensus

GUAM international consensus guideline on GU adverse events after prostate RT

ForProstate cancer pts receiving definitive or post-RP RT with GU toxicity

TL;DRDelphi panel (48 experts, ≥75% agreement): 76% favor moderate hypofx over SBRT at baseline IPSS 15–19; no dose-volume constraint reached consensus.

Reported via UroToday →

Why it mattersRadiation oncology

The technique read is that baseline IPSS now gates fractionation: 76% favored moderate hypofx over SBRT at IPSS 15–19, and MIRAGE (2-mm MRI-guided margins, late G≥2 GU 51% → 27%) was the margin evidence cited. Yet no bladder or urethral dose-volume constraint reached consensus, so planning-level GU sparing still rests on institutional choice.

Monday clinic

In an intact-prostate pt with baseline IPSS 15–19 weighing SBRT vs moderate hypofx, this panel leaned toward moderate hypofx; it does not address post-RP pts, and at IPSS ≥20 the question shifts toward urology referral for an outlet procedure before RT. The longer read

12 details 2 trials watching

Systematic review (183 articles) plus 3-round modified Delphi, May 2025 to Feb 2026. Consensus = ≥75% agreement; independent peer review, endorsed by ASTRO and ESTRO.

Panel of 48 experts from 15 countries: 34 radiation oncologists, 7 medical oncologists, 7 urologic oncologists across North America, Europe, Asia and Australia. Scope: acute medical mgmt, RT technique, outlet obstruction, urology referral, HBOT.

76% favored moderate hypofx over SBRT at baseline IPSS 15–19; 85% endorsed a full bladder at sim and treatment. No specific dose-volume constraint reached consensus.

Intact prostate: alpha blockers first for obstructive, anti-spasmodics first for irritative symptoms; post-RP: anti-spasmodics first. 80% against prophylactic medication; 80% add a 2nd agent rather than switch.

MIRAGE was cited for margin reduction (late G≥2 GU 51% → 27% with 2-mm MRI-guided vs 4-mm CT-guided). CHHiP, PROFIT, RTOG 0415 and HYDRA were cited as showing no consistent late GU excess with moderate hypofx; RICH-ART supports HBOT for radiation cystitis.

men receiving definitive or post-prostatectomy RT for prostate cancer with acute or late GU adverse events
Does not represent GI toxicity, sexual function, or non-prostate pelvic RT.

Several reported positions (74% IPSS ≥20 referral, 66% ≥12-wk wait, 52% SBRT after outlet procedure) fall below the ≥75% consensus bar. Panel is radonc-weighted, and this read comes from a conference summary, not the full manuscript.

Formalizes IPSS as a fractionation and referral gate and standardizes symptom-directed pharmacotherapy. It leaves dose-volume constraints, urethral contouring reliability and RT-specific drug evidence open; BEFORE, RadTARGET, RELIEF and DESTINATION-2 are named as ongoing.

SettingPreferred 1st lineSubsequent options (in order)
Intact prostate, obstructiveAlpha blockersPDE5-Is, NSAIDs, steroids, anti-spasmodics
Intact prostate, irritativeAnti-spasmodicsAlpha blockers, NSAIDs, phenazopyridine, cranberry
Post-prostatectomyAnti-spasmodicsNot specified in source
RecommendationAgreement
No prophylactic GU medication before symptom onset80%
Add 2nd agent rather than switch if 1st line inadequate80%
Alpha blockers do not/probably do not help post-RP74%
Moderate hypofx over SBRT at baseline IPSS 15–1976%
Full bladder at simulation and treatment85%
Refer for outlet procedure at IPSS ≥2074%
Wait ≥8 wk after outlet procedure before RT94%
Wait ≥12 wk after outlet procedure before RT66%
SBRT safe after outlet procedure once obstruction resolved52%
Prophylactic outlet procedure for severe LUTS85%
No outlet procedure when irritative symptoms predominate95%
IPSS thresholdPanelists
10–1416%
15–1961%
20–2421%
≥252%
IPSS thresholdPanelists
15–1934%
20–2447%
25–2915%
≥304%

Delphi consensus over a systematic review; agreement figures are opinion, not outcomes. First RT-specific GU toxicity framework, with core technique questions left unresolved.

📚 Sources · 📄 1 paper
📄 PAPER · UroToday
ASTRO 2026: International Consensus Guideline on Management of Genitourinary Adverse Events Associated with Prostate Cancer Radiation Therapy
Abstract
ASTRO 2026, prostate cancer, management of genitourinary adverse events associated with prostate cancer radiation therapy, MIRAGE trial.
📝 https://www.urotoday.com/conference-highlights/astro-2026/astro-2026-prostate-cancer/172248-astro-2026-international-consensus-guideline-on-management-of-genitourinary-adverse-events-associated-with-prostate-cancer-radiation-therapy.html?mtm_campaign=Dornisch_SocialASTRO26_ID172248
Consensus

ASTRO Clinical Practice Guideline: RT for Bladder Cancer

ForBladder cancer, high-grade cT1 NMIBC through metastatic disease

TL;DRTMT recommended (strong, high QoE) as alternative to RC for select cT2-4aN0M0 MIBC; bladder-alone 5500 cGy/20 fx or 6400-6480 cGy/32-36 fx.

Why it mattersRadiation oncology

Elective pelvic nodes stay conditional: no validated RCT vs bladder-only RT, and bladder-only series show ~7% pelvic nodal recurrence. Prostate and proximal urethra are conditionally added for base/neck, T4 or prostatic urethral involvement. Investigational concurrent IO warrants caution with moderately hypofractionated whole-pelvis chemoRT or >400 cGy/fx.

Monday clinic

In select cT2-4aN0M0 MIBC (solitary, <7 cm, no extensive CIS or hydronephrosis), this supports TMT with concurrent chemo as an alternative to RC; it gives only conditional, expert-opinion support to consolidative local therapy in cN2-3M0 disease after systemic response. The longer read

8 details 3 trials watching

Clinical practice guideline, not a trial. Systematic review of Ovid MEDLINE and Embase, January 2009 to November 18, 2024, yielding 153 studies; retrospective series limited to ≥65 pts (KQ1) and ≥100 pts (KQ2). Consensus by modified Delphi, threshold ≥75% agreement (≥90% for expert-opinion recs).

Adults (≥18 years) with bladder cancer treated with RT, across 4 KQs: bladder preservation, intact-bladder technique and dose, postoperative RT, noncurative RT. Out of scope: surgical management of MIBC, systemic-therapy specifics, intravesical therapy.

Preferred concurrent radiosensitizers: cisplatin ± 5-FU, 5-FU + mitomycin-C, or low-dose gemcitabine; carbogen and nicotinamide an alternative. Capecitabine ± mitomycin-C or single-agent 5-FU for pts ineligible for those agents.

Simulation and daily treatment supine with empty bladder and rectum; fiducials help delineate a tumor boost. 2 to 4 weeks from maximal TURBT to RT is typical, and post-TMT cystoscopy with biopsy follows at 8 to 12 weeks.

Caution, not absolute contraindication, for active inflammatory bowel disease, prior pelvic RT, or severely reduced bladder capacity. Elective nodal coverage is weighed against bowel toxicity.

Prior RTOG and NRG studies put the prostate in the field under 3-D CRT; the guideline narrows that to base/neck, T4 or prostatic urethral involvement. SWOG/NRG 1806 allowed bladder-only or bladder plus pelvic nodes, which the task force reads as equipoise on elective nodal coverage. Bladder-only series report ~7% pelvic nodal recurrence.

adults with bladder cancer from high-grade cT1 NMIBC through metastatic disease, with the evidence densest for urothelial cT2-4aN0M0 MIBC
Does not represent rarer aggressive subtypes (plasmacytoid, sarcomatoid, micropapillary, nested, small cell), which are left to individualized multidisciplinary management.

Search closed November 18, 2024 and excluded abstract-only reports. Histology guidance rests mostly on pure urothelial data, and ctDNA after TMT is not yet prospectively validated.

TMT is framed as curative treatment alongside RC within multidisciplinary shared decision-making, not a fallback for unfit pts. The guideline names access as the binding constraint: Black pts with MIBC are less likely to receive curative-intent cystectomy or chemoRT.

ScenarioRecommendationStrengthQoE
Select cT2-4aN0M0 MIBCTMT as alternative to RCStrongHigh
High-grade cT1N0M0 NMIBC, T1 recurrence, cystectomy declined/ineligibleTMT or clinical trialConditionalLow
cN1M0TMT or RC after neoadjuvant/induction systemic therapyStrongLow
cN2-3M0, stable/responding after systemic therapyConsolidative local therapyConditionalExpert opinion
Any TMTConcurrent radiosensitizing systemic therapyStrongHigh (chemo); Moderate (carbogen/nicotinamide)
TMT, cT3-4 or N1-3Neoadjuvant/induction systemic therapyStrongLow
Bladder preservationMaximal TURBT before chemoRTStrongLow
SettingDose-fractionationStrengthQoE
Bladder alone, intact cT1-4N0M05500 cGy/20 fx or 6400-6480 cGy/32-36 fxStrongHigh
cT1N0M0 option6120 cGy/34 fxUngraded remarkn/a
Bladder + elective nodes, cT2-4N0M0Nodes + bladder 4000-4600 cGy, bladder boost to 6400-6480 cGy/32-36 fxStrongLow
Nodal alternativeNodes 4000-4400 cGy/20 fx, bladder 5500 cGy/20 fxUngraded remarkn/a
Gross nodes, cT2-4N1-3M0Focal boost, tolerance-dependent; up to 6400-6480 cGy/32-36 fxConditionalLow
Escalation above 6400-6480 cGyNot outside trial or multi-institutional registryStrongModerate
ScheduleDaily RT, no mid-treatment break for cystoscopic assessmentStrongModerate
RecommendationStrengthQoE
Whole bladder full dose, or reduced dose to uninvolved bladder + partial tumor boost (cT2-4N0-3M0)StrongModerate
Elective pelvic nodes optional in cT2-4N0M0; higher-risk features (cT3-4, hydronephrosis, LVI, incomplete TURBT)ConditionalModerate
Prostate/proximal urethra for base/neck tumors, T4, or prostatic urethral involvementConditionalModerate
IMRT/VMAT with daily CBCT to verify bladder volumeStrongLow
Adaptive RT when coverage/OAR constraints or setup reproducibility failConditionalModerate

ASTRO guideline from systematic review (153 studies) plus modified Delphi; output is graded recommendations, not outcomes. Elective nodal RT and adjuvant RT stay conditional.

📚 Sources · 📄 1 paper
📄 PAPER Ballas, Leslie K.; Solanki, Abhishek A.; Baumann, Brian C. et al. · Practical Radiation Oncology (2026-09)
Radiation Therapy for Bladder Cancer: An ASTRO Clinical Practice Guideline
Consensus

BEACON-HCC

ForHCC across all stages, North American practice context

TL;DRNew North American HCC allocation framework; expert decisions 96.6% concordant with BEACON vs 72.4% with BCLC 2025 across 29 cases.

Why it mattersRadiation oncology

First major allocation framework to place EBRT/SBRT alongside TARE as a first-line locoregional option rather than a BCLC afterthought, extending to Class 1D (Vp1-2) and Class 3B (Vp3/4). The panel's own citation base for Class 3B is RTOG1112, which showed only a trend (p=0.06) for SBRT vs sorafenib, so the elevation runs ahead of randomised evidence.

Monday clinic

For a cirrhotic patient with unifocal HCC not eligible for resection or transplant, this framework treats SBRT as a legitimate first-line ablative option rather than a fallback; it does not apply to Class 4A, where the panel explicitly withholds EBRT outside symptom palliation. The longer read

9 details 4 trials watching

Modified Delphi consensus, 20 North American multidisciplinary experts, iterative discussion and voting over two rounds. Followed by a 29-case pilot concordance exercise against external experts.

Framework spans the full HCC spectrum, from unifocal ≤3 cm (Class 1A) to distant metastases (Class 4B). Class assignment keys on tumor burden, Vp level of portal invasion, and poor prognostic features (>8 cm, AFP >1000 ng/mL, poor differentiation).

EBRT including SBRT is named a first-line locoregional option in Classes 1A through 3A, on par with TARE, RFA/MWA, and TACE. No dose or fractionation is specified anywhere in the framework: the stated rationale is ablative dose delivered selectively to limit radiation-induced liver injury. In Class 4A, EBRT is not routinely indicated outside palliation of symptomatic disease.

Expert decisions matched BEACON in 28 of 29 cases (96.6%) vs 72.4% for BCLC 2025. The single discordant case was combination systemic plus locoregional therapy for vascular invasion reaching the right atrium.

BEACON classBCLC 2025AJCC v8Adaptation from BCLC
Class 1AVery early (0) or early (A)Stage 1A or 1BAligned; framework elevates SBRT and TARE
Class 1BEarly (A)Stage 1BAligned
Class 1CEarly (A)Stage 2Aligned
Class 1DAdvanced (C)Stage 2Macrovascular invasion may suit local or surgical therapy: TARE, SBRT, resection
Class 2Early (A)Stage 1A or 1BAligned; framework elevates SBRT and TARE
Class 3AIntermediate (B) or advanced (C)Stage 3AAligned; framework elevates SBRT and TARE
Class 3BAdvanced (C)Stage 3B or 4AMacrovascular invasion may be amenable to local therapy in selected cases
Class 4AIntermediate (B)Stage 3AExtensive intrahepatic spread treated as systemic process
Class 4BAdvanced (C)Stage 4BStage and treatment framework aligned

BCLC keeps radiation outside its core allocation algorithm; BEACON moves it in. The supporting evidence the panel cites is uneven: DOSISPHERE (ORR 71 vs 36%, OS 26.6 vs 10.7 mo) for personalized-dosimetry TARE is randomised, while the SBRT case in Class 3B rests on RTOG1112, which reached only p=0.06 for OS vs sorafenib.

North American multidisciplinary HCC practice where SBRT, TARE, and transplant are all locally available
Does not represent centers without radiation or interventional expertise, nor practice settings where the BCLC algorithm governs reimbursement or trial eligibility.

The 72.4% BCLC comparator was scored by BEACON's own authors against cases the same group selected, and 29 cases cannot exercise nine classes evenly. Round-1 per-class agreement is unreadable from the source table because vote counts and class labels arrived unpaired.

The framework's real claim is that intrahepatic burden and Vp level, not BCLC's stage buckets, should drive allocation, and that radiation-based modalities are burden-appropriate rather than stage-restricted. Whether that improves outcomes is untested: validation against empiric clinical data is deferred to the HCC-Live Consortium.

Delphi consensus framework, not an efficacy study. Concordance figures measure opinion against opinion. Elevates EBRT/TARE to first-line locoregional status in a formal allocation system.

📚 Sources · 📄 1 paper
📄 PAPER Singal, Amit G.; Agopian, Vatche G; Dawson, Laura A. et al. · Hepatology (2026-08)
BEACON-HCC: Best evidence and north american consensus on treatment allocation for hepatocellular carcinoma
Abstract
Background : Hepatocellular carcinoma (HCC) remains a major cause of cancer-related mortality. Optimal treatment decisions are challenging, and existing treatment allocation frameworks may not fully reflect the evolving therapeutic landscape or contemporary clinical practices in North America. Methods : Using a modified Delphi process, a multidisciplinary panel of 20 North American experts in hepatology, medical oncology, surgery, radiology, and radiation oncology developed a consensus-based treatment framework for HCC, termed the BEACON-HCC system. The framework was informed by current evidence and expert opinion through iterative discussion and voting. In a pilot study using 29 real-world patient cases, we assessed concordance between external expert recommendations and BEACON-HCC recommendations and Barcelona Clinic Liver Cancer (BCLC) 2025 treatment recommendations. Results : The BEACON-HCC treatment allocation framework diverges from prior frameworks by incorporating nuanced clinical features such as degree of intrahepatic tumor burden and vascular invasion, and adverse tumor prognostic markers, to align treatment allocation with tumor biology and therapeutic potential. Key innovations include the incorporation of emerging modalities such as external beam radiation therapy (EBRT), transarterial radioembolization (TARE), and systemic-locoregional combination therapies. In the pilot exercise, expert treatment decisions showed 96.6% concordance with BEACON-HCC recommendations and 72.4% concordance with BCLC recommendations. Conclusions : BEACON-HCC is a consensus-based framework for treatment allocation that incorporates the expanding range of therapeutic options available to patients in the North American HCC population. Expert treatment decisions showed a high concordance with the BEACON-HCC system; further validation using empiric clinical data is planned through the HCC-Live Consortium.
Consensus

IROCK RCC SABR contouring guidelines

ForLocalized RCC treated with SABR, incl. IVC thrombus, recurrence, post-RFA

TL;DRFirst international consensus on target delineation for localized RCC SABR: 16 experts, median DSC 0.85 vs consensus, >0.70 in every case.

Why it mattersRadiation oncology

The two contested target calls are settled: include the entire tumor thrombus and the entire RFA cavity, and these were also the cases with most variation (DSC 0.85 and 0.75; HD 64.60 mm in Case 1). The 5 mm PTV assumes 4DCT, vacuum cushion, IV contrast and daily CBCT, so a center without those shouldn't copy the margin.

Monday clinic

In a medically inoperable localized RCC with IVC tumor thrombus or recurrence after RFA, this supports covering the full thrombus or full ablation cavity in the iGTV; it does not settle the dose or fraction number, which the panel left institution-specific. The longer read

10 details

Contouring consensus: 16 IROCK radiation oncologists contoured 4 CT-only cases; a STAPLE algorithm produced the 95% consensus contour, refined over 2 online meetings (May and June 2024) until 100% agreement on statements.

Panel eligibility: ≥10 RCC SABR cases treated; 14 of 16 had treated ≥10 pts in the prior 12 months. Cases: >10 cm tumor with IVC thrombus, central tumor at the hilum, post-nephrectomy recurrence, post-RFA residual.

iGTV equals ITV since no microscopic-spread margin is added. Most common PTV: uniform 5 mm on iGTV with supine vacuum cushion, 4DCT, IV contrast and daily CBCT. Participants used 1, 3, or 5 fractions; OAR constraints drawn from FASTRACK-II and AQuOS-II protocols.

Overall median DSC 0.85 (range 0.40-0.95), MDA 2.17 mm, HD 9.00 mm; median DSC >0.70 in every case. Greatest variation in Case 1 (superior thrombus extent) and Case 4 (cavity inclusion).

CaseScenarioiGTV recommendation
1Tumor >10 cm with IVC tumor thrombusPrimary tumor + entire tumor thrombus; exclude bland thrombus
2Central tumor abutting renal hilumAll visible tumor, account for internal motion; may extend into hilum
3Local recurrence post-nephrectomyAll visible gross tumor; surgical clips need not be included
4Residual tumor post-RFAVisible gross recurrence + entire ablation cavity
CaseDSCMDA (mm)HD (mm)
10.85, 0.79-0.856.69, 5.88-8.7964.60, 64.44-86.40
20.90, 0.84-0.931.55, 1.00-2.097.92, 5.35-9.98
30.91, 0.88-0.931.42, 1.18-1.896.18, 6.00-7.12
40.75, 0.60-0.792.50, 2.12-2.999.00, 9.00-12.39

FASTRACK-II established prospective phase II support for RCC SABR; this document standardizes the target and OAR definitions that trial-era protocols left variable. AQuOS-II is prospectively testing whether ipsilateral parenchyma and hilum contours matter for toxicity.

localized RCC treated with SABR in centers with 4DCT, contrast and CBCT
Does not represent MRI-guided or adaptive workflows, where the 5 mm margin may differ.

CT-only images; MRI might have reduced variation. Participants did not recontour after consensus, so the post-consensus agreement is assumed rather than measured.

The guideline chooses OAR priority over coverage and accepts heterogeneous target dose, which trades some target coverage for bowel safety. Whether hilum or cortex sparing reduces renal toxicity remains unanswered and is deliberately left optional.

Expert contouring consensus; agreement metrics measure contour overlap, not outcome. Standardizes target definition for an emerging indication; not validated prospectively.

  • Does renal hilum or cortex sparing reduce renal toxicity?
  • Patterns of failure with the 5 mm PTV margin
  • Does MRI-based contouring reduce target variation?
📚 Sources · 📄 1 paper
📄 PAPER Dhar, Aneesh; Siva, Shankar; Tan, Vivian S. et al. · International Journal of Radiation Oncology*Biology*Physics (2026-05)
International Radiosurgery Oncology Consortium of the Kidney (IROCK) Contouring Guidelines for Renal Cell Carcinoma Treated With Stereotactic Ablative Radiation Therapy
Consensus

EANO Consensus Statement on Radiation Necrosis

ForPost-cranial-RT pts with a new enhancing lesion, glioma or brain metastases

TL;DRDelphi consensus: 53/57 statements reached ≥80% agreement across 20 experts; perfusion MRI + amino acid PET preferred, bevacizumab for steroid-refractory RN.

Why it mattersRadiation oncology

The dose-volume numbers are the transferable part: V12Gy ~10 cm³ carrying 5-10% symptomatic necrosis in single-fraction SRS, and hypofractionated brain+target V20Gy (3fx) or V24Gy (5fx) <20 cm³ holding RN needing resection under 4%. That is a planning constraint, and it gates the single-session vs hypofractionated choice for larger or eloquent-region metastases.

Monday clinic

For a patient 6-24 months out from SRS or cranial RT with a new enhancing lesion, this supports going to perfusion MRI plus amino acid PET before calling progression; it does not settle mixed lesions, where the panel still points to tissue. The longer read

11 details 5 trials watching

Three-round Delphi. 57 statements drafted after literature review across epidemiology-pathophysiology (n=8), causes (n=10), imaging (n=10), histopathology (n=9), management (n=20), plus an exploratory research set of 8. Consensus prespecified at ≥80% agreement on a 5-point Likert scale.

The voting panel, not patients: 15 volunteers (2 radiation/clinical oncologists, 4 neuro-oncologists, 4 medical oncologists, 2 neurosurgeons, 1 neuropathologist, 1 neuroradiologist, 1 nuclear medicine physician), expanded by 5 more in round 1 (4 neuro-oncologists, 1 radiation/clinical oncologist) to 20 total. Clinically the scope is RN after RT for primary glial or metastatic brain tumors.

RN is called uncommon below EQD2 ~40 Gy (α/β 2 Gy), rising with dose per fraction, total dose and irradiated volume. V12Gy ~10 cm³ carries a 5-10% symptomatic necrosis risk after single-session SRS; for hypofractionated SRT, brain-plus-target V20Gy (3fx) or V24Gy (5fx) <20 cm³ associates with <10% any necrosis and <4% RN requiring resection. Re-irradiation risk stays under 10% at cumulative EQD2 100-110 Gy and reaches up to 25% above 130 Gy.

Consensus reached on 53 of 57 statements after three rounds. Diagnostic and management statements are tabulated separately in the details; the four that failed to reach 80% are not identified in the available text.

ModalitySettingSensitivitySpecificity
T1 contrast-enhanced MRI aloneWHO grade 3-4 glioma68%77%
T1 contrast-enhanced MRI aloneBrain metastases79%76%
DSC rCBVGrade 3-4 glioma87-90%86-88%
DSC rCBVBrain metastases (418 lesions)83%78%
MR spectroscopy Cho/NAAGlioma (455 pts)88%86%
Amino acid PETBrain metastases (~400 pts)82%84%

The document's practical contribution is a decision sequence rather than a new treatment: advanced MRI first, amino acid PET to add confidence, tissue when doubt persists, and treatment triggered only by symptoms of >7 days with increasing severity. Its most consequential position is moving bevacizumab from rescue to an expected next step at a defined steroid threshold (dependence >4 weeks or dexamethasone 8 mg/day), which is a lower bar than many centres apply.

symptomatic cerebral RN after RT for glioma or brain metastases, in centres with perfusion MRI and amino acid PET access
Does not represent spinal or head-and-neck RN, pseudoprogression within the first months after chemoradiation, or the late enlarging cysts after SRT that the panel says are pathogenetically separate.

Agreement percentages measure how a self-selected 20-person European panel voted, and the panel skews neuro-oncology (8 of 20) over radiation oncology (3 of 20) for a complication defined by dose and volume. FET and F-DOPA availability is largely European, so the imaging algorithm's top tier is not reproducible in most centres worldwide. The 4 non-consensus statements are not enumerated in the accessible text, so the reader cannot see where the panel actually split.

Delphi expert-opinion document, no efficacy endpoint. Agreement measured against opinion, not outcomes; authors state absence of Level 1 evidence and call for randomised trials.

📚 Sources · 📄 1 paper
📄 PAPER Duerinck, Johnny; Van Den Bent, Martin; Brandal, Petter et al. · Neuro-Oncology (2026-07)
The European Association for Neuro-oncology (EANO) Consensus Statement on Radiation Necrosis
Abstract
Abstract Introduction Radiation necrosis (RN) complicates neuro-oncological care, mimicking tumor recurrence and lacking high-level evidence for standardized management. Methods A European Association for Neuro-Oncology (EANO) expert panel utilized a three-round Delphi process to create a comprehensive expert opinion document based on the available current scientific evidence. A series of statements, derived from the published literature were created by the experts in each field. Consensus was defined as ≥ 80% agreement using a 5-point Likert scale. Results After three rounds among 20 experts that included adaptation of statements, the Delphi process reached a consensus (≥80% agreement) on 53 statements out of 57. RN occurs in 4% to 30% of patients, typically appearing 6 to 24 months after radiotherapy for primary (glial) or metastatic brain tumors. Experts identified perfusion MRI and amino acid PET as the most suitable imaging modalities for differentiation from tumor recurrence. While histopathology remains the gold standard, identifying viable tumor cells in irradiated gliomas is challenging due to overlapping cytological features with reactive glia. For symptomatic management, corticosteroids may be tried, and bevacizumab is recommended for corticosteroid-refractory cases, with evidence suggesting profound efficacy even at low doses. Surgery is considered effective for rapid symptom relief and definitive diagnosis in accessible lesions. Laser Interstitial Thermal Therapy (LITT) can be considered an additional treatment option for symptomatic RN. Conclusions Despite the absence of Level 1 evidence, these Delphi-survey-formulated recommendations provide actionable guidance for clinical practice. There is a need for prospective randomized trials focusing on symptomatic RN.
Consensus

ESTRO OCSCC Post-op CTV Delineation Guidelines

ForResected oral cavity SCC proceeding to post-operative radiotherapy

TL;DRFirst ESTRO guideline for post-op CTV delineation in oral cavity SCC: GTV-P pre-op + 10 mm composited with surgical defect/flap + 5 mm.

Why it mattersRadiation oncology

The margin recipe is asymmetric and that is the operative detail: 10 mm around the re-created pre-op GTV-P but only 5 mm around the surgical defect or flap, composited rather than either alone. Fig 3.1/3.2 shows why, the re-created GTV-P extended superiorly beyond the defect into infratemporal fossa, a geographical miss if you contour the defect alone.

Monday clinic

In resected OCSCC going to PORT, this supports re-creating the pre-op GTV-P from diagnostic MRI alongside the defect or flap rather than contouring the operative bed alone; it does not extend to R2 resections or other head and neck subsites. The longer read

11 details 5 trials watching

ESTRO-convened multi-disciplinary expert group developing delineation guidelines through discussion and review of current evidence and international practice. Drafts were reviewed by HNSCC experts from countries outside the authorship (Japan, Hong Kong, Australia, Brazil, Mexico, Canada, Denmark, France, Spain, Poland, Ireland, UK) and modified on their feedback. No efficacy endpoint, no patient cohort.

Patients with oral cavity squamous cell carcinoma requiring post-operative radiotherapy, regardless of margin status and other histological risk factors. R2 resection (macroscopic residual disease) is explicitly out of scope. Companion background manuscript from the same group covers indications for PORT.

Planning CT 2.0 mm slices (range 1-3 mm), skull base to below sterno-clavicular joint, IV contrast mandatory, rigid co-registration with pre-op contrast-enhanced CT and/or MRI matched to C1-C3 vertebral bodies or nearby bone, not to soft tissue. CTV-P is the composite of GTV-P pre-op + 10 mm and surgical defect/flap + 5 mm, edited for bone, fascia, air, teeth and any intra-oral prosthesis. Nodal margin is 5 mm on GTV-N pre-op without pENE, 10 mm with pENE.

None. The stated aim is consistency of delineation to enable multi-institutional audit, clinical trials and RTQA. Authors position prospective audits of practice and outcomes as the route to establishing these volumes as standard of care.

resected oral cavity SCC receiving post-operative radiotherapy, including flap and non-flap reconstruction
Does not represent R2 resections, definitive (non-surgical) treatment, or non-oral-cavity head and neck subsites, which the authors flag as future work.

Extends the 2018 international CTV-P consensus for definitive HNSCC RT, whose 5+5 mm geometric expansion supplies the 10 mm used here around GTV-P pre-op. Cites the DAHANCA finding that geometric expansion is more conformal than anatomical margins, a post-hoc De-ESCALaTE analysis correlating the anatomical-to-geometric protocol change with lower late dysphagia, and non-randomised Dutch series where reducing the high-risk margin 10 mm to 6 mm cut salivary and constrictor dose. GORTEC's 2020 flap delineation guidance is named as an adjunct.

The 5 mm and 10 mm margins are imported from definitive-setting geometry and one surgical pathology series (>95 % of microscopic infiltration within 5 mm of GTV-P edge), not from post-operative recurrence mapping. The dose to dissected but uninvolved levels rests on a 1993 MD Anderson observation never tested prospectively, and is left to clinician discretion (EQD2 50-60 Gy). The whole method assumes accurate pre-op to planning CT co-registration, and the fallback where it fails is to treat the entire involved level, a larger volume.

The novel move is refusing to pick between the two available surrogates for a resected tumour: re-created pre-op GTV and operative bed are contoured independently and unioned, because each fails in a different direction. Fig 3.1 shows a GTV-P pre-op extending superiorly past the defect toward the infratemporal fossa, and Fig 8.1 a pectoralis major pedicled flap whose composite volume extends outside the oral cavity and is trimmed back. What is left unsettled is dose de-escalation to central flap tissue, where the guideline offers a flap avoidance structure for standardisation while stating there is a lack of data and consequently a lack of consensus.

VolumeIndicationEQD2 dose
CTV-P post-opPTV associated with post-op primary CTV60 Gy
CTV-P high-riskPositive (<1 mm) margin, whole CTV-P or localised stripover 60 Gy, e.g. 64-66 Gy
CTV-N1Involved nodal levels60 Gy
CTV-N2Undissected at-risk levels50 Gy
CTV-N2, dissected at-risk levelsOptimal dose unknown50 Gy to 60 Gy, clinician discretion
CTV-N high-riskPathological extranodal extensionover 60 Gy, e.g. 64-66 Gy

ESTRO expert guideline, no efficacy endpoint. Fills a documented gap (no prior post-op HNSCC CTV consensus); authors themselves position prospective audit as the validation step.

📚 Sources · 📄 1 paper
📄 PAPER Evans, Mererid; Bonomo, Pierluigi; Chan, Po Chung et al. · Radiotherapy and Oncology (2025-11)
Delineation of the post-operative primary tumour and nodal clinical target volumes in oral cavity squamous cell carcinoma: European Society for Radiotherapy and Oncology (ESTRO) clinical guidelines
Consensus

American Radium Society AUC: Local Intraprostatic Recurrence

ForIsolated intraprostatic recurrence after definitive prostate RT

TL;DRSevere GU toxicity 20% after salvage RP vs 5.6% SBRT, 9.6% HDR: panel prefers biopsy-confirmed reirradiation.

Why it mattersRadiation oncology

The modality recommendation is a toxicity argument, not an efficacy one: MASTER found adjusted 5-yr recurrence-free survival of 50% to 60% across modalities with no survival difference vs RP, so reirradiation wins on severe GU toxicity (5.6% SBRT, 9.6% HDR vs 20% RP). Target volume then follows concordance, focal when mpMRI and systematic biopsy agree, whole-gland when they do not.

Monday clinic

In a man with rising PSA after conventionally fractionated definitive prostate EBRT whose PSMA PET and mpMRI show isolated intraprostatic recurrence, this supports biopsy confirmation before reirradiation rather than ADT alone; it does not extend to recurrence after primary brachytherapy or to nodal or distant failure. The longer read

9 details 4 trials watching

PRISMA systematic review of PubMed and Embase (searched 28 June 2022) across four topics, excluding conference abstracts, non-English publications and series of fewer than five patients. A 12-member multidisciplinary panel of radiation oncologists, urologists and medical oncologists voted in two rounds by modified Delphi, with RAND methodology defining disagreement.

Scope is tier A disease, local-only intraprostatic radiorecurrence after definitive RT, with BCR defined as PSA 2.0 ng/ml above nadir. Evidence was restricted to men whose primary treatment was conventionally fractionated EBRT, and prior brachytherapy patients were excluded from the synthesis. Every variant presumes the patient wants curative-intent local salvage.

All accepted salvage schemas fit in six or fewer fractions. For focal salvage, GETUG-AFU 31 defines GTV by mpMRI plus choline PET with a 5-7 mm margin bound by the prostatic capsule; whole-gland salvage SBRT has prospective support from the Fuller series. Dose constraints and IGRT method are out of scope.

Long hormone courses are recommended against across all salvage scenarios. A short 4-6 mo LHRH agonist carries moderate consensus as a radiosensitizer with salvage SBRT in patients without cardiac history, weaker consensus with cardiac comorbidity, and classic ADT is preferred over novel hormonal agents.

The toxicity read that drives the reirradiation preference comes from pooled retrospective data that could not evaluate sexual toxicity and included no PSMA PET selection. Approaches that combine biopsy and ablation in one procedure are discouraged, since histologic confirmation must precede salvage.

No prior consensus guideline addressed intraprostatic radiorecurrence exclusively. The hormone-only comparators being displaced (Crook intermittent vs continuous ADT, TOAD immediate vs delayed, EMBARK enzalutamide MFS benefit) all enrolled before PET-based selection and none isolated a biopsy-confirmed, local-only cohort. RTOG 0526 reported after MASTER closed, adding prospective LDR support.

men with biopsy-confirmable, PSMA PET and mpMRI-localised isolated intraprostatic recurrence after conventionally fractionated definitive EBRT
Does not represent recurrence after primary brachytherapy or after moderate or ultrahypofractionated RT, nor nodal or distant failure (tiers B and C).

The search closed 28 June 2022 with an acknowledged lag to publication. MASTER carries between-study heterogeneity and follow-up asymmetry favoring older modalities, so its flat efficacy comparison is not a randomised one. The hormone recommendation rests on no qualifying study and is extrapolated from de novo intermediate-risk data.

Settled: image, biopsy with both systematic and targeted cores, then prefer reirradiation over hormones alone. Not settled: the modality for a second salvage, for castrate-resistant local recurrence, for short PSA doubling time, or after prior grade 3 toxicity, all of which drew panel disagreement.

VariantPanel position
Variant 1: isolated intraprostatic recurrenceReirradiation usually appropriate; cryotherapy or HIFU may be appropriate; ADT alone not recommended
Variant 2: short PSA doubling time, short interval to failureHIFU may be appropriate, but disagreement across all interventions; ADT alone not recommended
Variant 3: castrate-resistant local recurrenceDisagreement on intervention; androgen suppression uniformly not recommended
Variant 4: second local salvageDisagreement on which modality to select
Variant 5: prior grade ≥3 toxicityDisagreement; active surveillance may be appropriate; ADT can be considered
ModalitySevere GUSevere GI
Salvage RP (reference)20%1.8%
SBRT5.6%not reported in source
HDR brachytherapy9.6%0.0%, p < 0.01 vs RP
LDR brachytherapy9.1%not reported in source
ScenarioTarget volume
mpMRI and systematic biopsy agree on lesion locationFocal favored
History of grade ≥3 toxicity from initial RT courseFocal favored
Lesion occult on mpMRI, localised by PET plus systematic biopsyFocal or whole-gland both appropriate
mpMRI and systematic biopsy disagree on lesion locationWhole-gland preferred
Recurrent lesion in a different location to the index lesionWhole-gland preferred, focal appropriate in selected cases

Appropriate use criteria from a 12-member Delphi panel; the output is a recommendation grid, not an efficacy result. No trial endpoint, so efficacy verdicts do not apply.

📚 Sources · 📄 1 paper
📄 PAPER Valle, Luca F.; Jiang, Tommy; Rosenbloom, Ashton et al. · European Urology Oncology (2025-06)
American Radium Society Appropriate Use Criteria for the Workup and Treatment of Local Intraprostatic Recurrence of Prostate Cancer Following Definitive Radiotherapy