2026-11-08

CNS

HyTEC TCP modeling for vestibular schwannoma SRS alongside a LINAC planning comparison of DCA variants vs VMAT.

Confirmatory

SRS for Vestibular Schwannomas: TCP Analyses (HyTEC)

ForSporadic vestibular schwannoma, SRS or fSRS, non-NF2

TL;DRPooled model of 35 series and 5162 pts: 12 Gy single-fraction predicts 3-5y TCP of 91.2% (LQ) or 95.6% (LQ-L). No outcome data below 11 Gy.

Why it mattersRadiation oncology

The two models disagree on α/β (12.4 vs 2.97 Gy), which changes how fSRS ranks: LQ puts 18 Gy/3fx (93.6%) above 12 Gy x1 (91.2%), while LQ-L puts it below (94.0% vs 95.6%). Calling fractionation 'equivalent' therefore depends on the model chosen. Single-fraction dose reduction below 11 Gy has no outcome data behind it.

Monday clinic

In a sporadic VS being planned for SRS or fSRS, this supports the common 12-13 Gy/1fx, 18-21 Gy/3fx and 25 Gy/5fx prescriptions as all sitting high on the control curve. It does not extend to NF2-related tumors or salvage after prior resection. The longer read

12 details

Design

HyTEC literature review and pooled TCP model: 35 publications, 5162 pts. A 3-parameter Poisson model with α/β as a free parameter, fit by maximum likelihood under both LQ and LQ-L dose conversion.

Population & inclusion

Sporadic VS treated with SRS or fSRS. NF2 pts excluded, and the authors tried to exclude progression after prior resection. Pediatric pts and repeat SRS were not analyzed.

Radiotherapy

The most common prescriptions were 12 to 13 Gy in 1 fraction, 18 to 21 Gy in 3 fractions, or 25 Gy in 5 fractions. Gamma Knife, CyberKnife and linac series were pooled. The prescription was treated as the minimum GTV dose and the sole determinant of TCP.

Endpoints

3- to 5-year tumor control, using 5y when reported, otherwise 3y. Where both were given they were typically within 0%-3% of each other.

Results

LQ: EQD2 of 13, 19, 25 and 33 Gy predicted TCP of 80%, 90%, 95% and 98%. LQ-L: EQD2 of 18, 26, 35 and 45 Gy for the same levels. Per-regimen TCP is in the table above.

Regimen	LQ (α/β 12.4)	LQ-L (α/β 2.97)
10 Gy x1	85.0%	89.7%
11 Gy x1	88.4%	93.1%
12 Gy x1	91.2%	95.6%
13 Gy x1	93.5%	97.33%
18 Gy/3 fx	93.6%	94.0%
25 Gy/5 fx	97.2%	96.9%

vs leading data

The source cites prior comparative work that found SRS and fractionated stereotactic RT "equally effective", with no NTCP differences in hearing preservation, trigeminal toxicity or facial nerve toxicity. This model is consistent with that: every fSRS regimen modeled sits high on the curve.

Applies to

sporadic, non-NF2 VS treated with single-fraction SRS or 3- to 5-fraction fSRS at standard doses

Does not represent NF2-related tumors, salvage after resection, pediatric pts or single-fraction doses below 11 Gy.

Limitations

Only 26% of reports gave conformity indices, and none reported Dxx/Vxx, so dosimetry was reduced to the prescription. TCP at 0 Gy was assumed at 30%. There were too few data to model TCP by tumor volume.

Discussion

The curve is flat across standard prescriptions, so it cannot separate 12 from 13 Gy, or single-fraction from fSRS, on control alone. Toxicity and logistics should drive that choice. Whether control holds beyond 10y is still open.

Rationale

Dose-response model fit to pooled, mostly retrospective series with heterogeneous control definitions. It supports current prescriptions but adds no randomized or prospective dose-comparative data.

Open questions

Tumor control durability beyond 10 years after SRS
Control at single-fraction doses below 11 Gy
Volume-dependent TCP for larger schwannomas

Sourced from Soltys, Scott G. et al.

📚 Sources · 📄 1 paper

📄 PAPER Soltys, Scott G.; Milano, Michael T.; Xue, Jinyu et al. · International Journal of Radiation Oncology*Biology*Physics (2021-05)

Stereotactic Radiosurgery for Vestibular Schwannomas: Tumor Control Probability Analyses and Recommended Reporting Standards

doi

Radiation Meta-analysis Confirmatory

Caveats dominate

LINAC SRS Technique Comparison: DCA vs VMAT

ForLINAC-based single-target cranial SRS/SRT, Elekta Agility 5 mm MLC

TL;DRPaddick CI 0.78 VMAT vs 0.75 DCA+SSO+VDR vs 0.6 plain DCA across 11 replanned cases. VMAT needed 41 ± 17% more MU than DCA+SSO+VDR.

Why it mattersRadiation oncology

Against the optimized DCA+SSO+VDR variant, VMAT's dosimetric advantage shrinks to CI 0.78 vs 0.75 (p=0.03); GI (p=0.29) and V12Gy 11.14 vs 11.75 cc (p=0.38) did not differ, at the cost of MU 4040 vs 2818. On an Elekta 5 mm-leaf platform, SSO+VDR, not VMAT, captures most of the gain over plain DCA. The longer read

9 details

Design

Retrospective dosimetric replanning of 11 brain cases, each planned four ways (DCA, DCA+SSO, DCA+SSO+VDR, VMAT). Paired t-tests between adjacent techniques, p<0.05 significant.

Population & inclusion

7 solitary metastases, 2 meningiomas, 1 acoustic schwannoma, 1 pituitary adenoma. PTV 0.93 to 22.5 cc, median 4.99cc.

Radiotherapy

9 SRS and 2 SRT, 18 to 30Gy total. PTV = GTV + 2 mm; objective 95% of PTV covered by 95% of prescription. Elekta Versa HD, Agility 5 mm leaves, 6 FFF, Monaco Monte Carlo. DCA plans noncoplanar (couch angles ≥30 degrees apart); VMAT coplanar single arc.

Endpoints

Paddick CI, RTOG HI, Paddick GI, MU as a treatment-time proxy, and healthy-brain V12Gy (brain minus PTV).

Results

Each DCA refinement improved CI stepwise; VMAT edged DCA+SSO+VDR on CI only (p=0.03), with no difference in GI (p=0.29) or V12Gy (p=0.38) and higher MU (p=0.0007). DCA gave the most homogeneous dose (HI 1.17).

Metric	DCA	DCA+SSO	DCA+SSO+VDR	VMAT	p (DCA vs SSO / SSO vs VDR / VDR vs VMAT)
Paddick CI	0.6	0.69	0.75	0.78	0.0004 / 0.015 / 0.03
RTOG HI	1.17	1.22	1.26	1.28	0.008 / 0.04 / 0.06
Paddick GI	1.35	1.21	1.20	1.17	0.03 / 0.33 / 0.29
MU	2507	2724	2818	4040	0.001 / 0.20 / 0.0007
Brain V12Gy (cc)	16.75	14.13	11.75	11.14	0.10 / 0.01 / 0.38

vs leading data

Authors report CI direction matching Jessica et al and Lagerwaard et al (VMAT over DCA), and GI matching Chang et al. Chang et al reported VMAT needing higher MU than DCA by a factor of 2.37, larger than the gap here against SSO+VDR.

Applies to

single-lesion LINAC SRS/SRT planning on an Elekta Agility 5 mm MLC with Monaco

Does not represent multiple-metastasis single-isocenter plans, noncoplanar VMAT, cone-based or finer-leaf MLC platforms.

Limitations

Coplanar VMAT vs noncoplanar DCA means geometry and modulation are not separable. No delivery QA, measured beam-on time, or setup-error sensitivity analysis, despite the authors raising both. Mixed benign and malignant targets across a wide volume range in N=11.

Discussion

The defensible read is that SSO+VDR closes most of the DCA-to-VMAT gap; the authors' own claim that VMAT has shorter total treatment time rests on FFF dose rate and avoided couch entries, not a measured time.

Rationale

Dosimetric surrogates only, N=11 mixed histologies; beam geometry confounded with technique and VMAT's edge over DCA+SSO+VDR rests on CI alone.

Open questions

Does noncoplanar VMAT outperform optimized noncoplanar DCA?
Do dosimetric gains translate to lower radionecrosis rates?
How sensitive are VMAT gradients to setup error versus DCA?

Sourced from Venugopal, Ramya et al.

📚 Sources · 📄 1 paper

📄 PAPER Venugopal, Ramya; S., Sowmya Narayanan; Tiwari, Richa et al. · Asian Journal of Oncology (2022-07)

The Optimal Choice of Technique for Stereotactic Radiosurgery—A LINAC-Based Dosimetric Study between DCA, DCA-SSO, DCA-SSO-VDR, and VMAT

doi

Abstract

Abstract Introduction Advanced radiation therapy delivery techniques require greater understanding of various planning sequences and methods. The aim of this study is to determine a class solution that finds the best possible technique to deliver for stereotactic radiosurgery between dynamic conformal arc (DCA) techniques using various options such as DCA, DCA + SSO (segment shape optimization), and DCA + SSO + VDR (variable dose rate) using noncoplanar beam arrangement and volumetric modulated arc therapy (VMAT) using coplanar beams. Materials and Methods In this dosimetric study, 11 brain cases were retrospectively planned for various techniques and analyzed for the Paddick conformity index (CI), Radiation Therapy Oncology Group homogeneity index (HI), Paddick gradient index (GI), treatment time in terms of monitor units (MU) and normal brain dose (V12Gy). The paired t-test was performed to know the statistical significance between the techniques. Results In terms of CI, GI, and control of the normal brain dose, the VMAT plan was superior to other techniques. But, HI was found to be better with DCA. Above all, VMAT delivered higher MU than any other technique. The p-values between DCA + SSO and DCA, DCA + SSO + VDR and DCA + SSO, and VMAT and DCA + SSO + VDR are as follows: CI: 0.0004, 0.015, and 0.03; GI: 0.03, 0.33, and 0.29; HI: 0.008, 0.04, and 0.06; V12 Gy of normal brain: 0.1, 0.01, 0.38. VMAT requires approximately 41 ± 17% more MU than DCA + SSO + VDR. Conclusion VMAT using coplanar beams is preferable among all the techniques, considering the dosimetric parameters studied. If VMAT is not available in the facility, DCA + SSO + VDR technique using non coplanar beams can be used to deliver SRS treatment.

Radiation Retrospective Caveats dominate

Breast

Two joint ASTRO/ASCO/SSO guidelines: PMRT indications and volumes, plus RT safety by germline mutation status (TP53 the lone contraindication to intact-breast RT).

Consensus

Hereditary Breast Cancer ASCO-ASTRO-SSO Guideline

ForBreast cancer with germline BRCA1/2, PALB2, CHEK2, ATM or TP53 mutation

TL;DRRT not withheld for mutation status (strong rec), except germline TP53, where intact-breast RT is contraindicated; BCT stays open to BRCA1/2 carriers.

Why it mattersRadiation oncology

The panel graded the RT recommendations unevenly. Not withholding RT for BRCA1/2 or moderate-penetrance status is a strong rec on intermediate evidence, but the ATM rec rests on low evidence, so a toxicity concern is a counseling topic, not a reason to omit RT. TP53 is the only exclusion, and even there PMRT stays available with significant LRR risk.

Monday clinic

In a newly diagnosed BRCA1/2 or ATM carrier otherwise eligible for breast conservation, this supports keeping BCT plus indicated RT on the table; it does not extend to germline TP53 carriers, for whom intact-breast RT is contraindicated. The longer read

9 details 2 trials watching

Design

Joint ASCO/ASTRO/SSO expert panel; systematic review plus formal consensus with two voting rounds. 58 articles for local therapy, 6 RCTs (published 2017 to 2018) for systemic therapy.

Population & inclusion

Women with breast cancer carrying germline BRCA1/2, PALB2, CHEK2 or ATM mutations, early or advanced stage; TP53 addressed for RT. Panel states management should be largely the same for men.

Radiotherapy

RT should not be withheld because of mutation status after BCT or when PMRT is considered (Rec 6.1, strong). ATM carriers: offer RT when indicated (6.2). Germline TP53: intact-breast RT contraindicated, PMRT only with significant LRR risk (6.3).

Regimen

Metastatic BRCA carriers: platinum preferred over taxane if platinum-naive; olaparib or talazoparib as an alternative to chemo in metastatic HER2-negative disease, 1L to 3L. No routine platinum added to anthracycline/taxane (neo)adjuvant chemo; no PARPi in nonmetastatic disease.

Results

Round 1 agreement ranged 72% to 98%, mean 90%. One of 17 recs (moderate-gene CRRM) failed the 75% threshold and passed at 90% after revision.

Rec	Population	Recommendation	Evidence	Strength
6.1	BRCA1/2 or moderate-penetrance gene	RT not withheld for mutation status after BCT or when PMRT considered	Intermediate	Strong
6.2	ATM carriers	Offer RT when clinically indicated; discuss with those considering BCT	Low	Moderate
6.3	Germline TP53 carriers	Intact-breast RT contraindicated; mastectomy; PMRT only with significant LRR risk	Low	Moderate

Decision	BRCA1/2	Moderate-penetrance
BCT for index cancer	Not precluded; discuss CBC and ipsilateral new primary risk	Offer when BCT appropriate
CRRM	Discuss; lowers CBC, no proven survival gain	Not based predominantly on mutation status
Nipple-sparing mastectomy	Reasonable in selected pts	Reasonable in selected pts
Surveillance without bilateral mastectomy	Annual mammogram + MRI	Annual mammogram + MRI
Metastatic chemo	Platinum preferred over taxane if platinum-naive	No platinum efficacy data
PARPi, metastatic HER2-negative	Olaparib or talazoparib, 1L to 3L	No supporting data
(Neo)adjuvant	No routine platinum add-on; PARPi not recommended	No data

vs leading data

Systemic recs lean on TNT for platinum and OlympiAD/EMBRACA for PARPi. TNT included only 11 BRCA carriers with ER-positive disease, so the platinum preference extrapolates thinly to ER-positive carriers.

Applies to

germline BRCA1/2 and moderate-penetrance (PALB2, CHEK2, ATM) carriers with breast cancer weighing BCT, RT, CRRM or systemic options

Does not represent somatic-only BRCA tumors, where PARPi efficacy data are absent.

Limitations

Rec 4.1 wording ('offered') diverges from Table 2 and the abstract ('discussed') for BRCA1/2 CRRM. ATM pathogenicity is unsettled for most missense variants, which confounds the RT toxicity literature the panel reviewed.

Discussion

The RT message is permissive: genotype is not a reason to omit indicated RT outside TP53. The adjuvant PARPi stance (Rec 10) predates the OlympiA readout and is the rec most likely to have aged.

Rationale

Formal-consensus guideline; RT recs rest on intermediate to low evidence from nonrandomised series. Agreement figures measure panel opinion, not outcomes.

Open questions

Does heterozygous ATM status raise RT toxicity or contralateral risk?
Do PARP inhibitors work in PALB2, CHEK2 or ATM carriers?

not yet PARP-inhibitor on Advanced Metastatic Breast Cancer in Germline PALB2 Mutations Carriers Phase 2

n=12 · primary completion 2024-09 · single-arm niraparib in germline PALB2 MBC, BRCA wt

active Olaparib In Metastatic Breast Cancer Phase 2

n=114 · primary completion 2025-07 · olaparib in MBC with CHEK2, ATM or PALB2 mutations
Platinum vs anthracycline neoadjuvant chemo in BRCA carriers

Sourced from Tung, Nadine M. et al.

📚 Sources · 📄 1 paper

📄 PAPER Tung, Nadine M.; Boughey, Judy C.; Pierce, Lori J. et al. · Journal of Clinical Oncology (2020-06)

Management of Hereditary Breast Cancer: American Society of Clinical Oncology, American Society for Radiation Oncology, and Society of Surgical Oncology Guideline

doi

Abstract

PURPOSE To develop recommendations for management of patients with breast cancer (BC) with germline mutations in BC susceptibility genes. METHODS The American Society of Clinical Oncology, American Society for Radiation Oncology, and Society of Surgical Oncology convened an Expert Panel to develop recommendations based on a systematic review of the literature and a formal consensus process. RESULTS Fifty-eight articles met eligibility criteria and formed the evidentiary basis for the local therapy recommendations; six randomized controlled trials of systemic therapy met eligibility criteria. RECOMMENDATIONS Patients with newly diagnosed BC and BRCA1/ 2 mutations may be considered for breast-conserving therapy (BCT), with local control of the index cancer similar to that of noncarriers. The significant risk of a contralateral BC (CBC), especially in young women, and the higher risk of new cancers in the ipsilateral breast warrant discussion of bilateral mastectomy. Patients with mutations in moderate-risk genes should be offered BCT. For women with mutations in BRCA1/ 2 or moderate-penetrance genes who are eligible for mastectomy, nipple-sparing mastectomy is a reasonable approach. There is no evidence of increased toxicity or CBC events from radiation exposure in BRCA1/ 2 carriers. Radiation therapy should not be withheld in ATM carriers. For patients with germline TP53 mutations, mastectomy is advised; radiation therapy is contraindicated except in those with significant risk of locoregional recurrence. Platinum agents are recommended versus taxanes to treat advanced BC in BRCA carriers. In the adjuvant/neoadjuvant setting, data do not support the routine addition of platinum to anthracycline- and taxane-based chemotherapy. Poly (ADP-ribose) polymerase (PARP) inhibitors (olaparib and talazoparib) are preferable to nonplatinum single-agent chemotherapy for treatment of advanced BC in BRCA1/ 2 carriers. Data are insufficient to recommend PARP inhibitor use in the early setting or in moderate-penetrance carriers. Additional information available at www.asco.org/breast-cancer-guidelines .

Consensus / guideline Consensus

Consensus

PMRT ASTRO-ASCO-SSO Guideline

ForAdults with breast cancer undergoing mastectomy, upfront or after NST

TL;DRPMRT recommended for pN1 (Strong/High) and post-NST cT4/cN2-3 or ypN+; conditional for ypN0 after cT1-3N1/cT3N0; moderate hypofractionation preferred.

Why it mattersRadiation oncology

The pN1 omission remark is written for pts after ALND, so it does not directly cover the SLNB-only axilla now common in practice. Moderate hypofractionation is preferred with or without reconstruction, and IMN coverage is individualized by tumor location, size and nodal extent, which moves fractionation and nodal-volume defaults for most PMRT cases.

Monday clinic

In cT1-3N1 or cT3N0 disease converting to ypN0 after NST, this frames PMRT as a shared decision, with omission reasonable at ypT0N0; it does not extend to initial cT4 or cN2-3, where PMRT stands regardless of response. The longer read

12 details 5 trials watching

Design

Multidisciplinary ASTRO-ASCO-SSO task force answering four key questions via systematic review and a predefined consensus methodology. Inclusion required ≥50 pts for RCTs/meta-analyses and ≥100 for nonrandomized or retrospective studies; retrospective studies excluded for KQ1. Reviewed by 17 peer reviewers plus public comment.

Population & inclusion

Adults (≥18 years) with breast cancer undergoing mastectomy, upfront or after NST. Out of scope: inflammatory breast cancer, DCIS after mastectomy, locoregional recurrence, reirradiation, oligometastatic or palliative disease, phyllodes and breast sarcoma.

Radiotherapy

PMRT defined as chest wall/reconstructed breast plus ipsilateral regional nodes, including IMNs. Moderate hypofractionation preferred; conventional fractionation acceptable in rare cases, and an equal option with reconstruction. CT-based 3D-CRT, IMRT when 3D-CRT falls short, DIBH, bolus only for skin involvement, positive superficial margins or LVI.

vs leading data

The pN1 recommendation rests on the EBCTCG meta-analysis, which the panel notes was limited to trials initiated by 1995 and predates HER2-directed therapy and immunotherapy. The ypN0 recommendation draws on ACOSOG Z1071 analyses, the NSABP B-51/RTOG 1304 primary-outcomes abstract, and the RAPCHEM registry.

Applies to

adults undergoing mastectomy for invasive breast cancer with curative intent, upfront or after NST

Does not represent inflammatory disease, recurrent disease, reirradiation, or oligometastatic/palliative settings.

Limitations

pT1-2N0 omission is graded Strong on Low evidence, and its exception list (TNBC, high grade, LVI, young age, central/medial tumors) is unquantified. The ypN0 Moderate grade leans on pooled secondary analyses, retrospective series and a registry. Large registry database studies were excluded throughout.

Discussion

The operative content sits in the implementation remarks, not the headline grades: pN1 omission for favorable pN1mic/low-burden pN1a, ypT0N0 omission, and chest wall alone for select pT3N0. What stays unsettled is RT for the cN1 → ypN0 pt, the only Conditional call in the post-NST table.

Results

Scenario	Recommendation	Strength	QoE
pN1	PMRT recommended	Strong	High
Any pT4	PMRT recommended, even without other risk factors	Strong	High
pT3N0	PMRT conditionally recommended	Conditional	High
pT1-2N0	PMRT not recommended	Strong	Low
Positive margins, no other indication	Chest wall/reconstructed breast alone	Conditional	Expert opinion

Scenario	Recommendation	Strength	QoE
Initial cT4 or cN2-3	PMRT regardless of pathologic response	Strong	Moderate
ypN1	PMRT recommended	Strong	Moderate
cT1-3N1 or cT3N0 → ypN0	PMRT conditionally recommended	Conditional	Moderate
cT1-2N0 → ypN0	PMRT not recommended	Strong	Moderate
Positive margins after NST	PMRT recommended	Strong	Expert opinion

Scenario	Recommendation	Strength	QoE
Any PMRT	Chest wall/reconstructed breast + axillary, supra/infraclavicular, IMNs	Strong	High
No reconstruction	Moderate hypofractionation	Strong	High
Reconstruction	Moderate hypofx (preferred) or conventional	Strong	Moderate (hypofx)
T4 or close/positive margins	Chest wall/scar boost	Conditional	Low
Nodal disease not surgically addressed	Nodal boost	Strong	Expert opinion

Rationale

Joint ASTRO-ASCO-SSO guideline from a 104-study systematic review; output is graded recommendations, not a measured outcome. Reframes indications around NST response.

Open questions

PMRT omission in cN1 converting to ypN0 after NST

not yet De-escalation of RNI in Breast Cancer Patients With pN0 After Neoadjuvant Therapy Phase NA

n=100 · primary completion 2028-06 · RNI de-escalation in biopsy-proven cN1 → ypN0 after NST
Hypofractionated PMRT toxicity with reconstruction

recruiting Hypofractionated vs Conventional RT After Prosthetic Breast Reconstruction Phase 3

n=506 · primary completion 2029-03 · phase 3 43.5/15 vs 50/25 after prosthetic reconstruction

recruiting Hypofractionated vs. Conventionally Fractionated Postmastectomy Radiotherapy After Implant-Based Reconstruction Phase NA

n=534 · primary completion 2033-10 · hypo vs conv PMRT post-implant; NI unplanned reoperation
IMN irradiation benefit in the modern systemic era

not yet Internal Mammary Node Irradiation After Neoadjuvant Systemic Therapy for Breast Cancer Phase 3

n=1760 · primary completion 2032-07 · phase 3 ± IMNI in ypN+ after NST; DFS primary

recruiting Internal Mammary Lymph Nodes Irradiation in High-risk Breast Cancer After Neoadjuvant Chemotherapy Phase 3

n=722 · primary completion 2032-07 · phase 3 IMNI vs none, ypN+ post-NAC; DFS primary

Sourced from Jimenez, Rachel B. et al.

📚 Sources · 📄 1 paper

📄 PAPER Jimenez, Rachel B.; Abdou, Yara; Anderson, Penny et al. · Journal of Clinical Oncology (2025-10)

Postmastectomy Radiation Therapy: An ASTRO-ASCO-SSO Clinical Practice Guideline

doi

Abstract

ASCO Guidelines provide recommendations with comprehensive review and analyses of the relevant literature for each recommendation, following the guideline development process as outlined in the ASCO Guidelines Methodology Manual . ASCO Guidelines follow the ASCO Conflict of Interest Policy for Clinical Practice Guidelines . Clinical Practice Guidelines and other guidance (“Guidance”) provided by ASCO is not a comprehensive or definitive guide to treatment options. It is intended for voluntary use by clinicians and should be used in conjunction with independent professional judgment. Guidance may not be applicable to all patients, interventions, diseases or stages of diseases. Guidance is based on review and analysis of relevant literature, and is not intended as a statement of the standard of care. ASCO does not endorse third-party drugs, devices, services, or therapies and assumes no responsibility for any harm arising from or related to the use of this information. See complete ASCO and ASTRO disclaimers in Appendix 1 (online only) for more. PURPOSE This guideline provides recommendations on use of postmastectomy radiation therapy (PMRT) in breast cancer treatment. Updated recommendations detail indications for PMRT in the upfront surgical setting and after neoadjuvant systemic therapy, and provide guidance on appropriate target volumes, dosing, and treatment techniques. METHODS A multidisciplinary American Society for Radiation Oncology–ASCO–Society of Surgical Oncology task force addressed four key radiation therapy (RT) questions in patients with breast cancer who undergo mastectomy: (1) indications for PMRT after upfront surgery, (2) indications for PMRT after neoadjuvant systemic therapy followed by surgery, (3) appropriate PMRT volumes and dose-fractionation regimens, and (4) treatment techniques. Recommendations were based on a systematic review and created using a predefined consensus-building methodology for quality of evidence grading and strength of recommendation. RECOMMENDATIONS After upfront mastectomy, PMRT is indicated for most patients with node-positive breast cancer and select patients with node-negative disease. PMRT is also recommended after neoadjuvant systemic therapy for patients presenting with locally advanced disease and for those with residual nodal disease at the time of surgery. PMRT is conditionally recommended for patients with cT1-3N1 or cT3N0 breast cancer with pathologically negative nodes after neoadjuvant systemic therapy (ypN0). When PMRT is delivered, treatment to the ipsilateral chest wall or reconstructed breast and regional lymphatics is recommended, with moderate hypofractionation preferred, but with conventional fractionation approaches acceptable in rare cases. Computed tomography–based volumetric treatment planning with 3-dimensional conformal RT is recommended, with intensity-modulated RT advised when three-dimensional conformal RT is unable to achieve treatment goals. Deep inspiration breath-hold techniques are also recommended for normal tissue sparing. For patients with skin involvement, positive superficial margins, and/or lymphovascular invasion, use of a bolus is recommended, but routine use of tissue-equivalent bolus is not recommended. Additional information is available at www.asco.org/breast-cancer-guidelines .

Radiation Curative Consensus / guideline Consensus

Oligometastatic / Mets

Caveats dominate

Adrenal SBRT Tumor Control Probability Modeling (HyTEC)

ForAdrenal metastases treated with SBRT, no prior adrenal RT

TL;DRPoisson TCP fit to pooled adrenal SBRT series: 1-yr LC >95% at BED10 116.4 Gy (EQD2 ≈97 Gy), fit P<.0001.

Why it mattersRadiation oncology

The 95% LC point sits at BED10 116.4 Gy (EQD2 ≈97 Gy), reachable with 45 Gy/3 fx (112.5) or 55 Gy/5 fx (115.5); NRG-BR001 already prescribes 45 Gy/3 fx. Dose inputs were IDL-corrected median prescriptions, not GTV DVHs, and every series used motion management, so the target transfers only with ITV, compression, breath-hold or gating in place.

Monday clinic

For a previously unirradiated adrenal metastasis where adjacent OAR tolerances allow, this supports planning above the 40 Gy/5 fx series median toward the modeled LC target; it does not extend to adrenal reirradiation or to choosing SBRT over adrenalectomy. The longer read

10 details 1 trial watching

Design

HyTEC literature review plus dose-response model. PubMed search Jan 2007 to Mar 2017 returned 250 results; included series ranged 6 to 49 lesions (6-48 pts). 1-yr LC fit to a Poisson TCP model by maximum likelihood, CIs by profile likelihood.

Population & inclusion

Adrenal metastases, lung the dominant primary, plus kidney, liver, melanoma and others. Mostly single-institution retrospective series. All but 1 series excluded prior adrenal RT.

Radiotherapy

Median dose 40 Gy (mean 37.2 Gy), median 5 fx (range 1-27), prescribed to the 70% to 100% IDL. PTV margins 0 to 10 mm. All series reported motion management: 4DCT/ITV, compression, breath-hold, gating or CyberKnife tracking.

Endpoints

Modeled endpoints were 1-yr LC and 1-yr OS. LC was RECIST-based in most series; 3 used PET/CT progression.

Results

LC fit P<.0001; 1-yr LC >95% at BED10 116.4 Gy (EQD2 ≈97 Gy). OS also showed a dose-response (P<.001) with wide CIs.

Parameter	Local control	Overall survival
D50 (Gy EQD2)	34.6 (95% CI 27.1-45.4)	44.7 (95% CI 33.5-60.6)
γ50	0.4996 (95% CI 0.248-0.814)	0.4546 (95% CI 0.157-0.796)
Fit χ2	57.5, P<.0001	44.7, P<.001

Schedule	BED10
45 Gy / 3 fx	112.5 Gy
55 Gy / 5 fx	115.5 Gy
Casamassima: 36 Gy / 3 fx to 70% IDL	just over 139 Gy at isocenter

vs leading data

A later meta-analysis (39 studies) predicted 1-yr LC of 70.5%, 84.8% and 92.9% at BED10 60, 80 and 100 Gy, within this model's CI. Direction matches the BED10 ≥100 Gy LC association reported for SBRT in early-stage NSCLC. NRG-BR001 (phase 1) prescribes 45 Gy/3 fx.

Applies to

previously unirradiated adrenal metastases treated with SBRT under motion management

Does not represent adrenal reirradiation or the SBRT vs adrenalectomy decision.

Limitations

Competing distant-death risk in small cohorts degrades the 1-yr LC estimates. Neither PTV margin nor IDL could be tied to LC, so the model gives no margin guidance. Circle-weighted study points, not patient-level data.

Discussion

Durability is the open issue: two later series at BED10 85.5 and 72 Gy lost LC at 2 and 3 years, suggesting dose affects durability. The OAR feasibility of reaching BED10 116.4 Gy near bowel and stomach is left to the planner.

Rationale

Dose-response fit to small retrospective series using study-level median prescriptions, not patient DVHs; no prospective validation, so the BED10 116.4 Gy target is model-derived.

Open questions

Durability of LC beyond 1 year at BED10 116.4 Gy

recruiting Stereotactic Magnetic Resonance Guided Radiation Therapy Phase NA

n=397 · primary completion 2028-06 · MR-guided SBRT, adrenal met cohort, tumor control endpoint
SBRT vs adrenalectomy for adrenal oligometastases
Optimal PTV margin and motion management for adrenal SBRT

Sourced from Stumpf, Priscilla K. et al.

📚 Sources · 📄 1 paper

📄 PAPER Stumpf, Priscilla K.; Yorke, Ellen D.; El Naqa, Issam et al. · International Journal of Radiation Oncology*Biology*Physics (2021-05)

Modeling of Tumor Control Probability in Stereotactic Body Radiation Therapy for Adrenal Tumors

doi

Radiation Meta-analysis Caveats dominate

🧠 CNS

SRS for Vestibular Schwannomas: TCP Analyses (HyTEC)

LINAC SRS Technique Comparison: DCA vs VMAT

🎀 Breast

Hereditary Breast Cancer ASCO-ASTRO-SSO Guideline

PMRT ASTRO-ASCO-SSO Guideline

🎯 Oligometastatic / Mets

Adrenal SBRT Tumor Control Probability Modeling (HyTEC)

CNS

Breast

Oligometastatic / Mets