Palliative Radiation Oncology - Board Review Summary

PART I - THE PALLIATIVE RT MINDSET: TRIAGE, GOALS, AND DOSE SELECTION

Management Paradigm + Dose Anchors

Clinical problemDefault management frameCommon RT / intervention anchor
Uncomplicated painful bone metastasisRT is highly effective. Choose fractionation by prognosis, logistics, prior RT, target size, and retreatment tolerance.8 Gy x 1, 20 Gy / 5, 24 Gy / 6, or 30 Gy / 10.
High-risk long-bone lesionAssess fracture risk before RT alone. Mechanical instability is a surgical problem first.Use Mirels; score ≥9 generally favors prophylactic fixation, then postop RT commonly 30 Gy / 10.
Postoperative orthopedic hardwareRT improves local control and reduces symptomatic recurrence. Treat after wound healing.Start about 2-4 weeks postop when feasible; cover the involved metastasis and hardware/surgical bed per operative anatomy.
Painful spine metastasis without MSCCSeparate non-mechanical tumor pain from instability. Use SINS and surgical input for mechanical pain.Conventional RT: 8 Gy x 1, 20 Gy / 5, 30 Gy / 10. SBRT only for selected stable patients.
Metastatic spinal cord compression (MSCC)Oncologic emergency. Steroids, MRI entire spine, spine surgery assessment, then surgery + RT or urgent RT.Dexamethasone 10 mg IV load then 4 mg q6h is a classic board regimen; urgent RT often 8 Gy x 1, 20 Gy / 5, or 30 Gy / 10.
Superior vena cava syndrome (SVCS)Urgent but not always an immediate RT emergency. Stent first for airway compromise, cerebral edema, or hemodynamic instability.Stent can relieve symptoms in 48-72 hours; RT ranges from 8-10 Gy x 1 to 30 Gy / 10; chemo first for lymphoma, SCLC, germ cell tumors when stable.
Thoracic symptoms from lung cancerTreat hemoptysis, cough, dyspnea, chest pain, obstruction. Use bronchoscopy/stent/laser for immediate central airway obstruction.Good PS: often 30 Gy / 10 or higher-equivalent schedule. Poor PS/logistics: 20 Gy / 5, 17 Gy / 2 weekly, or 10 Gy x 1.
Bleeding pelvic, gynecologic, bladder, rectal, or fungating massHemostasis, symptom control, wound care, transfusion/IR when needed. Use short regimens for poor PS.Common anchors: 8 Gy x 1, 20 Gy / 5, 30 Gy / 10; pelvic Quad Shot 14-14.8 Gy / 4 BID can be repeated.
Head and neck palliationSymptoms include pain, dysphagia/odynophagia, bleeding, ulceration, airway compromise, malodor, cranial neuropathy.Quad Shot 14-14.8 Gy / 4 BID over 2 days, repeat every 3-4 weeks for 3-4 cycles; selected fit patients may receive 30 Gy / 5 or longer split courses.
Painful liver tumor burdenUse antiemetic/steroid premedication and protect functional liver. Distinguish whole-liver palliation from ablative liver SBRT.Whole-liver palliation: 8 Gy x 1, 21 Gy / 7, or 30 Gy / 15. Selected liver SBRT often needs uninvolved liver reserve.
Radiopharmaceutical palliation / systemic radionuclide therapyBest when disease distribution and target biology fit the radiopharmaceutical better than spot EBRT.Radium-223 for symptomatic bone-predominant mCRPC without known visceral disease; Lu-177-PSMA for PSMA-positive mCRPC per current label.
Re-irradiationRetrieve prior DICOMs whenever possible; convert to EQD2/BED; account for interval, volume, serial OARs, and expected benefit.Re-treat bone pain after adequate response interval; spine/cord, brachial plexus, bowel, brainstem, optic apparatus, and skin drive feasibility.

What Makes Palliative RT Different?

Core board principle: palliative RT is a symptom-directed intervention, not just a shorter definitive regimen. The best plan maximizes near-term quality of life while minimizing travel burden, acute toxicity, treatment interruptions, and conflict with systemic therapy.

First-Visit Triage Checklist

  • Clarify the symptom: pain, neurologic deficit, bleeding, obstruction, dyspnea, dysphagia, mass effect, wound drainage, or impending fracture.
  • Decide urgency: MSCC, cauda equina, airway compromise, uncontrolled hemorrhage, and severe SVCS may require same-day multidisciplinary action.
  • Separate biology from mechanics: RT helps tumor pain; it does not stabilize an unstable spine or long bone quickly enough when mechanical failure is the main problem.
  • Estimate prognosis: very short prognosis favors 8 Gy x 1, 10 Gy x 1, or 20 Gy / 5; longer prognosis can justify 30 Gy / 10, SBRT, or postop treatment.
  • Coordinate systemic therapy: ask about radiosensitizers, immunotherapy, targeted agents, anti-VEGF therapy, marrow reserve, and whether rapid systemic response is expected.
  • Plan for response timing: bone pain often improves over days to weeks, not immediately; steroids, analgesics, and palliative care are part of the RT plan.
Board trap: do not reflexively simulate every metastatic lesion. Treat the lesion causing the symptom, the lesion about to cause a serious event, or selected oligometastatic/oligoprogressive disease where durable local control changes the disease course.

PART II - BONE METASTASES: PAIN, FRACTURE RISK, POSTOP RT, RETREATMENT

Bone Metastasis Workup

QuestionHigh-yield answerBoard pearl
Is the pain malignant?Assess pain location, movement-dependence, night pain, neurologic symptoms, analgesic response, and correlation with imaging.Mechanical pain with weight bearing or movement should trigger stability/fracture assessment before RT alone.
Does the patient need biopsy?Biopsy is important for a solitary bone lesion without known cancer, first metastatic relapse when histology will change management, or discordant biology.Do not irradiate away the only accessible diagnostic site unless urgent palliation requires it.
Which imaging?MRI is best for marrow/spine/neural elements; CT helps cortical destruction, fracture, and biopsy planning; X-ray helps long-bone cortical involvement.For appendicular lesions, image the whole involved bone if fixation is being considered.
What are common skeletal events?Pain is most common. Reduced mobility, pathologic fracture, hypercalcemia, and cord/nerve compression are the major morbidity patterns.About 10-20% of patients with bone metastases can develop pathologic fracture in many series; risk is site- and histology-dependent.

Mirels Score for Long-Bone Fracture Risk

Category1 point2 points3 points
SiteUpper limbLower limbPeritrochanteric
PainMildModerateFunctional / severe
Lesion typeBlasticMixedLytic
Cortical involvement<1/3 cortex1/3-2/3 cortex>2/3 cortex
Interpretation: Mirels ≤7 usually supports observation/RT as appropriate; 8 is a gray zone requiring orthopedic judgment; ≥9 generally favors prophylactic fixation before RT.

Conventional EBRT Dose Selection

ScenarioReasonable regimensHow to choose
Uncomplicated painful non-spine bone metastasis8 Gy x 1, 20 Gy / 5, 24 Gy / 6, 30 Gy / 10Pain relief is similar across regimens; single fraction is convenient but has higher retreatment rates.
Painful spine metastasis without neurologic compromise8 Gy x 1, 20 Gy / 5, 30 Gy / 10Assess SINS. Mechanical instability or fracture risk is not solved by RT alone.
Multiple myeloma / plasmacytoma palliationOften 20 Gy / 5-10; consider 30 Gy / 10 for durable local control or cord-risk situationsMyeloma is radiosensitive; avoid excessive dose when marrow reserve is poor.
Postoperative long bone / hardwareCommonly 30 Gy / 10Treat after wound healing; cover the surgical bed, hardware tract, and original involved bone anatomy when appropriate.
Bone metastasis retreatment8 Gy x 1 or 20 Gy / 5 are common; use composite dose for spine/OAR-adjacent sitesWait long enough to see initial response when clinically safe, often at least 4 weeks for pain response.
Extensive painful bony diseaseHemibody RT: upper half about 6 Gy x 1, lower half about 8 Gy x 1Consider when radiopharmaceuticals are unavailable/contraindicated; lung block and marrow reserve matter.

Landmark Bone Pain Evidence

Dutch Bone Metastasis Study: 8 Gy x 1 and 24 Gy / 6 produced similar pain response, with median response around 3 weeks; retreatment was higher after single fraction.
RTOG 9714: breast/prostate painful bone metastases treated with 8 Gy x 1 vs 30 Gy / 10 had similar pain response. Multifraction RT caused more acute GI toxicity, while single fraction required more retreatment.
Chow meta-analysis: single- and multifraction RT had similar overall and complete pain response; retreatment was more common after single-fraction treatment.

Pain Flare and Response Timing

Bone pain flare can occur in up to about 40% of patients, most often in the first 5 days, and usually lasts 1-2 days. A common prophylaxis/treatment approach is dexamethasone 4 mg BID x 5 days when not contraindicated. Pain response is often noticeable by 1-3 weeks; analgesics should be continued and tapered only as symptoms improve.

Prophylactic RT to High-Risk Asymptomatic Bone Metastases

Gillespie / MSKCC phase II: prophylactic RT to selected high-risk asymptomatic bone metastases reduced skeletal-related events compared with standard care. High-risk definitions included bulky lesions, hip/shoulder/sacroiliac involvement, long-bone cortical involvement, and junctional spine sites. This is practice-informing but should not override orthopedic evaluation for unstable long bones.

PART III - SPINE METASTASES, SBRT, AND METASTATIC SPINAL CORD COMPRESSION

SINS: Mechanical Stability Before Radiation

SINS domainHigh-yield scoring ideaPractical implication
LocationJunctional spine scores highest; mobile spine intermediate; semirigid/rigid lower.Junctional areas fail mechanically and deserve early spine input.
PainMechanical pain is the most important clinical red flag.Pain with movement/loading is not simply "tumor pain."
Bone lesionLytic > mixed > blastic for instability risk.RCC, thyroid, lung, and myeloma lesions can be structurally destructive.
AlignmentSubluxation/translation or de novo deformity increases score.Alignment change is a surgical/stabilization concern.
CollapseGreater vertebral body collapse increases score.RT may help pain but will not rapidly restore load-bearing strength.
Posterolateral involvementBilateral pedicle/facet/costovertebral involvement increases score.Posterior element involvement increases instability risk.
Interpretation: SINS 0-6 stable, 7-12 potentially unstable, 13-18 unstable. A score >7 should prompt surgical/spine consultation in most board-style scenarios.

Bilsky / ESCC Scale

GradeDescriptionBoard implication
0Bone-only disease; no epidural extension.RT or SBRT based on symptoms, stability, prognosis, and histology.
1aEpidural impingement without thecal sac deformation.Potential SBRT candidate if stable and no neurologic deficit.
1bThecal sac deformation without cord abutment.SBRT may be feasible with adequate cord separation and constraints.
1cSpinal cord abutment without compression.Higher caution; separation surgery may be needed for durable SBRT dose.
2Cord compression with visible CSF around cord.Multidisciplinary urgent decision; surgery often considered if appropriate.
3Cord compression without visible CSF.True high-grade MSCC; surgery + RT favored when feasible.

MSCC Initial Management

Classic board sequence: recognize neurologic red flags -> give dexamethasone -> urgent MRI of the entire spine with contrast -> spine surgery and radiation oncology evaluation -> surgery + postop RT for selected surgical candidates, or urgent RT if surgery is not appropriate.
  • Symptoms: back pain is most common; weakness, gait change, sensory loss, radicular pain, saddle anesthesia, and bowel/bladder dysfunction are emergencies.
  • Steroids: common regimen is dexamethasone 10 mg IV load then 4 mg q6h; some guidelines use 16 mg/day. Avoid very high-dose 96-100 mg/day regimens because toxicity increases without clear benefit.
  • Imaging: MRI entire spine is preferred because noncontiguous disease is common; CT myelogram is an alternative when MRI is not possible.
  • Biopsy: obtain tissue if no known diagnosis, discordant progression, or histology will change therapy, as long as urgent treatment is not delayed unsafely.
  • Most important prognostic factor: pretreatment neurologic function. Patients treated rapidly after loss of ambulation are more likely to recover walking.

Surgery + RT Versus RT Alone

Patchell trial: direct decompressive surgery plus RT improved ambulation and duration of ambulation compared with RT alone in carefully selected patients. The trial excluded highly radiosensitive histologies such as lymphoma, myeloma, leukemia, and germ cell tumors, so do not overapply surgery to every MSCC case.

MSCC RT Fractionation

ScenarioTypical regimenBoard logic
Poor prognosis, not surgical, urgent decompression not feasible8 Gy x 1Modern guidelines support single fraction for many nonsurgical MSCC patients; convenient and fast.
Intermediate prognosis or larger field20 Gy / 5Common balance between convenience and durability.
Longer prognosis, radiosensitive tumor, postop, or concern for durable local control30 Gy / 10Traditional board-friendly regimen, especially when retreatment would be difficult.
Postoperative spine RTOften 30 Gy / 10, after recoveryStart after wound healing, often about 2-4 weeks; longer delay may be needed after major reconstruction/corpectomy.
Previously irradiated MSCCIndividualized conventional re-RT or SBRT after surgical separationComposite cord/cauda dose and neurologic urgency drive the answer.

MSCC Fractionation Trials to Know

SCORAD III: 8 Gy x 1 did not formally meet noninferiority to 20 Gy / 5 for ambulatory status at 8 weeks, but outcomes were close and the trial supports single fraction for selected poor-prognosis patients.
SCORE-2: 20 Gy / 5 was noninferior to 30 Gy / 10 in intermediate- to poor-prognosis MSCC, supporting shorter-course RT when durability is less critical.

Spine SBRT / SRS

Use SBRT when...Avoid or pause SBRT when...Dose anchors
Good PS, durable prognosis, limited spine disease, radioresistant histology, oligometastatic/oligoprogressive disease, or re-irradiation with acceptable cord dose.High-grade epidural compression with neurologic deficits, unstable spine, severe vertebral collapse, no safe cord/cauda separation, or inability to meet constraints.Common regimens: 16-18 Gy x 1, 24 Gy x 1-2, 24-30 Gy / 3, or 30 Gy / 5.
SBRT planning pearl: ideal cord/cauda separation is often at least about 3 mm. Vertebral compression fracture risk rises with lytic disease, baseline collapse, spinal deformity, and high single-fraction dose, especially ≥20 Gy per fraction.
SC.24: spine SBRT 24 Gy / 2 improved complete pain response compared with conventional 20 Gy / 5, with better local control in longer follow-up. This supports SBRT for carefully selected painful spine metastases when anatomy and stability are favorable.
NRG/RTOG 0631: single-fraction spine SRS 16-18 Gy x 1 was not superior to conventional 8 Gy x 1 for pain response at 3 months. Practical takeaway: SBRT benefit depends on patient selection, dose/fractionation, endpoint, and whether durable local control matters.

PART IV - SVCS AND THORACIC PALLIATION

Superior Vena Cava Syndrome

ScenarioBest initial moveRT / systemic anchor
Severe SVCS with airway compromise, cerebral edema, syncope, or hemodynamic compromiseEndovascular stent first when feasible; supportive head elevation and oxygen.RT or systemic therapy follows based on histology and stage; stents often improve symptoms within 48-72 hours.
Stable SVCS, unknown histologyComplete diagnostic workup and staging if it can be done safely.Do not reflexively start RT before tissue unless symptoms are dangerous.
SCLC, lymphoma, germ cell tumorSystemic therapy is often first because response can be rapid.RT reserved for refractory symptoms, nonresponding disease, or combined definitive strategy.
NSCLC or less chemosensitive advanced malignancyRT is appropriate for symptom palliation when stent is not required or after stent.8-10 Gy x 1, 20 Gy / 5, or 30 Gy / 10; for potentially curable disease, consider short high-dose start then adapt to definitive fractionation.
Board trap: steroids and diuretics are commonly used but have uncertain benefit in malignant SVCS; steroids can obscure lymphoma diagnosis. The emergency is the airway/brain/hemodynamics, not the CT finding alone.

Palliative Thoracic RT for Lung Cancer

Symptom / settingManagement frameCommon regimen
HemoptysisRT is effective for malignant bleeding; brisk arterial bleeding may need bronchoscopy or IR first.20 Gy / 5 or 30 Gy / 10; 10 Gy x 1 for very poor PS/logistics.
Cough, chest pain, dyspnea from thoracic tumorRT helps symptoms; integrate opioids, antitussives, steroids when indicated, and palliative care.Good PS: 30 Gy / 10 or higher-equivalent. Poor PS: 20 Gy / 5, 17 Gy / 2 weekly, 10 Gy x 1.
Central airway obstructionBronchoscopy, laser, debulking, or stent if immediate airway relief is needed.RT after stabilization; avoid waiting days for RT response when airway is critically compromised.
Pleural effusion causing dyspneaDrainage, pleurodesis, or indwelling catheter usually matters more than RT.RT does not reliably palliate fluid physiology unless focal tumor obstruction is the driver.
Incurable stage III with good PS and prognosis >3 monthsConcurrent chemotherapy with palliative-intent thoracic RT can be considered selectively, but toxicity rises.ASTRO 2018 update supports selected concurrent therapy; not a default for frail metastatic patients.
Dose-selection pearl: higher-dose thoracic palliation can modestly improve symptom scores and survival in good-PS patients but increases esophagitis. Short schedules are preferred when PS, travel, prognosis, or systemic therapy timing dominate.

PART V - HEMOSTATIC, HEAD AND NECK, AND PELVIC PALLIATION

Hemostatic RT Framework

Bleeding scenarioFirst questionsRT anchor
Slow malignant bleeding from pelvic, bladder, gynecologic, rectal, skin, or head and neck tumorIs the patient stable? Is bleeding venous/oozing vs arterial? What is platelet count/coagulation status? Is transfusion or embolization needed?8 Gy x 1, 20 Gy / 5, or 30 Gy / 10.
Brisk arterial bleeding or unstable patientStabilize, transfuse, reverse coagulopathy when appropriate, and involve IR/surgery/endoscopy.RT can consolidate after stabilization but is rarely the fastest way to stop life-threatening hemorrhage.
Recurrent bleeding after prior RTReview prior dose to bowel, bladder, skin, mucosa, femoral heads, spinal cord, brachial plexus, and vessels.Re-RT may be feasible with shorter fields/fractionation; toxicity and fistula risk can dominate.

Head and Neck Palliative Regimens

RegimenDoseUse case / caution
Quad Shot14-14.8 Gy / 4 fx, BID over 2 days with at least 6 hours between fractions; repeat every 3-4 weeks for up to 3-4 cyclesExcellent board regimen for frail patients, mucosal symptoms, bleeding, or bulky unresectable/recurrent H&N disease.
Hypofractionated course30 Gy / 5 fx, often spaced at least several days apartUseful for selected patients with better PS and no prior high-dose RT to the region.
Christie-style course50 Gy / 16 fxLonger palliative local-control approach for fitter patients with longer expected survival.
Split-course H&N palliationExamples include 30 Gy / 10, break, then additional 30-36 Gy / 10-12 if toleratedCan balance response and mucosal toxicity; reassess after initial course.
H&N re-irradiationCurative-intent reRT often 60-72 Gy IMRT in selected patients; SBRT 35-44 Gy / 5 is used in selected small-volume casesNot routine palliation. Avoid if tumor abuts brainstem/spinal cord or if poor PS/distant progression makes toxicity unjustified.
H&N board pearl: the Quad Shot is not a one-time 14 Gy treatment; it is a repeatable cyclical regimen. It is useful because the built-in reassessment prevents overcommitting frail patients to a long toxic course.

Pelvic Palliation

ProblemTypical approachDose / trial hook
Bleeding bladder tumorShort-course RT is effective; coordinate cystoscopy, transfusion, anticoagulation plan, and catheter management.21 Gy / 3 and 35 Gy / 10 had similar symptom outcomes in MRC BA09-style bladder palliation.
Gynecologic bleeding / pelvic painUse EBRT for hemostasis and pain; brachytherapy may be considered when anatomy and goals support it.20 Gy / 5, 30 Gy / 10, or 14-14.8 Gy / 4 BID repeated.
Rectal bleeding, pain, tenesmus, obstruction riskRT can reduce bleeding/pain; surgical diversion or stent may be needed for obstruction.20 Gy / 5 or 30 Gy / 10; reRT in rectal cancer may use carefully planned 30-50 Gy ranges depending on prior dose.
Fungating skin/chest wall/pelvic massCombine RT with wound care, odor control, infection management, and social support.8 Gy x 1, 20 Gy / 5, 30 Gy / 10; electrons or bolus may be needed for superficial disease.

PART VI - VISCERAL AND SOFT-TISSUE PALLIATION

Visceral Palliation Quick Hits

SiteSymptoms / selectionRT anchor
Liver tumor burdenPain, capsular discomfort, nausea/anorexia, fever/night sweats, jaundice in refractory liver metastases or HCC. Premedicate with antiemetic and consider steroid.Whole-liver palliation: 8 Gy x 1, 21 Gy / 7, or 30 Gy / 15. CCTG HE1 supports 8 Gy x 1 for painful hepatic cancer.
Liver oligometastasis / dominant lesionSelected good-PS patients with preserved liver function, limited lesions, and adequate uninvolved liver volume.Ablative SBRT often 48-54 Gy / 3 when safe; not the same as whole-liver palliation.
Adrenal metastasisPain, hemorrhage, adrenal insufficiency, IVC/renal vessel compromise, or oligometastatic local control.Conventional palliation: 20 Gy / 5, 30 Gy / 10. SBRT examples include 36 Gy / 3, 32 Gy / 4, 40 Gy / 5-10, individualized by stomach/bowel/kidney.
Renal mass / RCC primary palliationBleeding, pain, local invasion, or selected cytoreductive/oligometastatic strategy.Conventional 20 Gy / 5 or 30 Gy / 10; renal SBRT 30-40 Gy / 5 appears in modern studies but is selected and OAR-limited.
Splenomegaly / hematologic palliationPainful massive spleen, hypersplenism, poor surgical candidate.Very low-dose splenic RT is often used, such as small fractions to about 5-10 Gy total, with close CBC monitoring.
Bulky nodal or soft-tissue massPain, edema, plexopathy risk, venous/lymphatic obstruction, skin compromise.20 Gy / 5, 30 Gy / 10, or SBRT for selected oligoprogression when OARs permit.

Whole-Liver RT Evidence

CCTG HE1: in painful refractory hepatic cancer, single-fraction whole-liver RT 8 Gy x 1 plus best supportive care improved pain response compared with best supportive care alone. This makes 8 Gy x 1 a high-yield modern option for liver-dominant pain when liver function and field size are acceptable.
Board trap: liver SBRT and whole-liver palliation are different treatments. SBRT is for focal durable control with adequate liver reserve; whole-liver low-dose RT is for symptom relief from diffuse liver tumor burden.

PART VII - CNS PALLIATION AND LEPTOMENINGEAL-STYLE SCENARIOS

Brain Metastasis Palliative Frame

ScenarioDefault frameRT / supportive anchor
Limited brain metastases, reasonable PSSRS preferred when feasible to preserve cognition.Dose by size/location; small intact lesions often 20-24 Gy x 1.
Extensive brain metastases, reasonable prognosis, not SRS-suitableHA-WBRT + memantine when hippocampal avoidance is oncologically safe.Common WBRT regimen 30 Gy / 10; hippocampi D100% ≤9 Gy, Dmax ≤16 Gy.
Poor prognosis brain metastasesSupportive care, steroids for edema, antiseizure therapy only if seizure/indication, hospice, or short-course WBRT for meaningful symptoms.20 Gy / 5 or best supportive care; QUARTZ-style logic supports avoiding reflex WBRT in poor-prognosis NSCLC.
Leptomeningeal diseaseFocal RT to symptomatic bulky/nodular sites, cauda/cranial nerve symptoms, or CSF-flow obstruction; systemic/intrathecal therapy when appropriate.WBRT 30 Gy / 10 or focal 20 Gy / 5/30 Gy / 10; CSI is selected, uncommon, and marrow/GI-toxic in adults.
CNS palliative pearl: symptomatic brain metastases still need upfront local therapy in most cases. Drug-first deferral is for carefully selected asymptomatic patients with highly CNS-active systemic options and reliable MRI follow-up.

PART VIII - RADIOPHARMACEUTICALS AND SYSTEMIC RADIONUCLIDE THERAPY

Radiopharmaceutical Board Table

AgentBest-fit disease stateDose / outcome hooksCommon cautions
Radium-223 dichlorideCastration-resistant prostate cancer with symptomatic bone metastases and no known visceral metastatic disease.55 kBq/kg IV q4 weeks x 6. ALSYMPCA improved OS about 14.9 vs 11.3 months and delayed first skeletal event.Check marrow reserve. Avoid combination with abiraterone plus prednisone/prednisolone because fracture/mortality concerns increased.
Lu-177 vipivotide tetraxetan (Pluvicto)PSMA-positive mCRPC. Current FDA indication includes patients treated with ARPI who are appropriate to delay taxane chemotherapy, and the older post-ARPI/post-taxane setting.7.4 GBq / 200 mCi IV q6 weeks x 6. PSMAfore improved rPFS after ARPI; VISION established benefit after ARPI and taxane.Requires PSMA PET selection. Monitor CBC, renal function, xerostomia, nausea, fatigue, marrow suppression, and radiation-safety instructions.
Lu-177 DOTATATESomatostatin-receptor-positive neuroendocrine tumors after appropriate imaging and systemic evaluation.Typically delivered by nuclear medicine using PRRT protocols.Renal protection, marrow reserve, carcinoid symptom management, and amino-acid infusion toxicity matter.
When EBRT still winsFocal fracture risk, MSCC, focal neurologic deficit, single dominant painful lesion, post-op hardware, or urgent hemostasis.Spot RT gives targeted rapid local control and can be combined/sequenced with radiopharmaceuticals.Do not use systemic radionuclide therapy as a substitute for stabilization or urgent cord decompression.
Radiopharm pearl: EBRT and radiopharmaceutical therapy answer different questions. EBRT is best for an anatomically urgent problem; radiopharmaceuticals are best for systemic target-positive disease when marrow reserve and label criteria fit.

PART IX - RE-IRRADIATION, OLIGOPROGRESSION, AND SIMULATION-FREE WORKFLOWS

Re-Irradiation Checklist

StepWhat to doWhy it matters
Retrieve prior recordsGet prior DICOM dose, structures, plans, prescription, fractionation, and setup notes whenever possible.Paper dose summaries are not enough for cord, bowel, brachial plexus, optic, brainstem, and skin decisions.
Convert biologyUse EQD2/BED with explicit alpha/beta and tissue recovery assumptions.Composite nominal dose can mislead when fraction sizes differ.
Assess intervalLonger intervals and small volumes are safer; recurrent symptoms at least several months after prior RT are more favorable.NICE supports considering further spine RT after good prior response and recurrent symptoms at least 3 months later.
Define goalAnalgesia, hemostasis, decompression, local control, or bridge to systemic therapy.ReRT toxicity is only justified by a clear clinical benefit.
Choose techniqueConventional fields for broad symptom palliation; IMRT/SBRT for reRT near critical OARs or oligoprogression.Conformality helps only if setup, imaging, and constraints are robust.

Oligoprogressive Disease Is Not the Same as Routine Palliation

Use metastasis-directed therapy when ablating a few progressing sites can preserve an effective systemic regimen, delay next systemic therapy, or consolidate limited metastatic disease in a patient with good PS and controlled extracranial disease. Common hypofractionated anchors include 30 Gy / 3, 35-40 Gy / 5, or disease-site-specific SBRT regimens; a practical anchor for selected oligoprogression is 10 Gy x 3.

Simulation-Free / Diagnostic CT-Based Palliative RT

DART-style workflow: diagnostic CT-based palliative planning can dramatically reduce time in the cancer center for selected simple palliative cases. The key is careful case selection, adequate diagnostic image quality, and safety checks so table position, immobilization, and OAR visibility are not compromised.
Board trap: simulation-free workflows are for selected straightforward palliative treatments, not unstable spine SBRT, re-irradiation near serial organs, or anatomy where daily setup uncertainty changes safety.

CROSS-CUTTING HIGH-YIELD POINTS

  • Palliative RT is symptom-directed: treat the clinical problem, not every radiographic metastasis.
  • Single-fraction bone RT works: 8 Gy x 1 gives similar pain relief to multifraction regimens, with higher retreatment.
  • Mechanical pain changes the answer: use Mirels for long bones and SINS for spine; unstable lesions need orthopedic/spine input.
  • Postoperative bone RT: wait for wound healing when feasible and cover the operative anatomy/hardware at risk.
  • MSCC is an emergency: steroids, MRI entire spine, surgical evaluation, and RT/surgery decision.
  • MSCC steroid anchor: dexamethasone 10 mg IV then 4 mg q6h; avoid very high-dose steroid regimens.
  • Neurologic function before treatment predicts outcome: ambulatory patients are more likely to remain ambulatory.
  • Patchell applies to selected surgical candidates: do not overapply it to lymphoma, myeloma, leukemia, germ cell tumors, or nonsurgical frail patients.
  • Spine SBRT is not for unstable high-grade cord compression: consider separation surgery when durable SBRT dose is desired.
  • SVCS: stent first for severe airway/cerebral/hemodynamic compromise; chemo first for chemosensitive histologies when stable.
  • Thoracic palliation: 30 Gy / 10 for good PS/longer prognosis; 20 Gy / 5, 17 Gy / 2, or 10 Gy x 1 for poor PS/logistics.
  • Quad Shot: 14-14.8 Gy / 4 BID over 2 days, repeated every 3-4 weeks, is a key H&N and pelvic palliation regimen.
  • Hemostatic RT: RT helps malignant oozing/bleeding, but unstable arterial bleeding requires stabilization and often IR/endoscopy first.
  • Whole-liver palliation: 8 Gy x 1 is a modern evidence-supported option for painful hepatic cancer in selected patients.
  • Radiopharmaceuticals: radium-223 is for symptomatic bone-predominant mCRPC without known visceral disease; Lu-177-PSMA requires PSMA-positive mCRPC and current label criteria.
  • Re-irradiation: think composite EQD2, interval, volume, and serial OARs before prescription.
  • Short prognosis means short treatment: long courses that outlive the patient are a failure of palliative judgment.

CONSOLIDATED DOSE TABLE

Clinical settingDose / planning ruleUse case
Uncomplicated painful bone metastasis8 Gy x 1Most convenient standard regimen; higher retreatment
Uncomplicated painful bone metastasis20 Gy / 5; 24 Gy / 6; 30 Gy / 10Equivalent pain relief; consider for longer prognosis, large fields, or lower retreatment preference
Bone pain flare prophylaxisDexamethasone 4 mg BID x 5 daysSelected patients without contraindication
Postoperative long bone / hardware30 Gy / 10Common postop palliation/local-control anchor
Bone metastasis retreatment8 Gy x 1 or 20 Gy / 5After adequate response interval; composite dose for OAR-adjacent sites
Hemibody upper half6 Gy x 1Extensive bony pain when radiopharm unsuitable
Hemibody lower half8 Gy x 1Extensive bony pain when radiopharm unsuitable
MSCC steroid anchorDex 10 mg IV load -> 4 mg q6hClassic emergency regimen; taper after surgery/RT begins
Nonsurgical MSCC8 Gy x 1Guideline-supported for many patients, especially limited prognosis
MSCC / spine palliation20 Gy / 5 or 30 Gy / 10Intermediate/longer prognosis, large field, postoperative, or durable-control preference
Spine SBRT common anchors16-18 Gy x 1; 24 Gy x 1-2; 24-30 Gy / 3; 30 Gy / 5Selected stable patients; respect cord/cauda constraints
Thoracic palliation, good PS30 Gy / 10Common NSCLC symptom regimen
Thoracic palliation, poor PS/logistics20 Gy / 5; 17 Gy / 2 weekly; 10 Gy x 1Short-course symptom relief
SVCS RT8-10 Gy x 1 to 30 Gy / 10After stent when severe; chemo first for chemosensitive tumors if stable
Head and neck Quad Shot14-14.8 Gy / 4 BIDRepeat every 3-4 weeks for 3-4 cycles if benefiting
H&N hypofractionation30 Gy / 5Selected fitter patients, usually no prior high-dose overlap
Hemostatic RT8 Gy x 1; 20 Gy / 5; 30 Gy / 10Bleeding pelvic, bladder, GI, skin, H&N tumors
Bladder palliation21 Gy / 3 or 35 Gy / 10MRC BA09-style options
Whole-liver palliation8 Gy x 1Painful hepatic cancer; CCTG HE1 modern anchor
Whole-liver older options21 Gy / 7; 30 Gy / 15Selected patients with adequate liver reserve
Adrenal conventional palliation20 Gy / 5 or 30 Gy / 10Pain, bleeding, mass effect
Adrenal SBRT examples36 Gy / 3; 32 Gy / 4; 40 Gy / 5-10Selected lesions, OAR-limited
Limited brain metastasis SRS20-24 Gy x 1 for small lesionsSize/location/OAR dependent
WBRT30 Gy / 10Extensive brain mets, reasonable prognosis; use HA + memantine when safe
Short-course WBRT20 Gy / 5Poor prognosis but symptomatic intracranial palliation desired
Radium-22355 kBq/kg q4 weeks x 6mCRPC, symptomatic bone mets, no known visceral disease
Lu-177-PSMA-6177.4 GBq / 200 mCi q6 weeks x 6PSMA-positive mCRPC per current FDA label

KEY LANDMARK TRIALS / GUIDELINES (MEMORIZE)

Study / guidelineDisease / syndromeOne-line takeaway
ASTRO Bone Metastases Guideline 2024Symptomatic bone metastasesMaintains 8 Gy x 1, 20 Gy / 5, 24 Gy / 6, and 30 Gy / 10 as standard conventional options; SBRT conditionally appropriate for selected good-PS patients.
Dutch Bone Metastasis StudyPainful bone metastasesSingle-fraction and multifraction RT have similar pain response; single fraction has higher retreatment.
RTOG 9714Breast/prostate painful bone mets8 Gy x 1 and 30 Gy / 10 provide similar pain relief; retreatment higher with single fraction.
Chow meta-analysisPainful bone metastasesConfirms similar pain response between single and multifraction RT, with more retreatment after single fraction.
NCIC SC.20Bone metastasis re-irradiation8 Gy x 1 is a reasonable retreatment option and less burdensome than multifraction therapy.
Gillespie / MSKCC phase IIHigh-risk asymptomatic bone metsProphylactic RT reduced skeletal-related events in selected high-risk lesions.
SC.24Painful spine metastasesSBRT 24 Gy / 2 improved complete pain response compared with conventional 20 Gy / 5 in selected patients.
NRG/RTOG 0631Painful spine metastasesSingle-fraction SRS 16-18 Gy x 1 did not improve pain response versus 8 Gy x 1 conventional RT.
PatchellSelected MSCCSurgery + RT improves ambulation outcomes versus RT alone in carefully selected surgical candidates.
SCORAD IIIMSCC8 Gy x 1 and 20 Gy / 5 have close ambulatory outcomes; single fraction useful in selected poor-prognosis patients.
SCORE-2MSCC20 Gy / 5 noninferior to 30 Gy / 10 for intermediate/poor prognosis MSCC.
NICE NG234 2023Spine metastases / MSCCMRI within 24 hours for suspected MSCC; urgent RT within 24 hours if not surgical; uses 8 Gy x 1 unless high side-effect risk.
ASTRO Palliative Thoracic NSCLC Guideline / 2018 updateThoracic symptomsHigher-dose palliation may help good-PS patients; shorter schedules fit poor PS/logistics; concurrent chemo only selected patients.
MRC BA09Bladder palliation21 Gy / 3 and 35 Gy / 10 are both reasonable symptom-palliation schedules.
CCTG HE1Painful hepatic cancerWhole-liver 8 Gy x 1 improved pain response compared with best supportive care alone.
ALSYMPCAmCRPC bone-predominant diseaseRadium-223 improved OS and delayed skeletal events in symptomatic bone-metastatic CRPC without known visceral disease.
VISIONPost-ARPI/post-taxane PSMA+ mCRPCLu-177-PSMA-617 improved outcomes in PSMA-positive mCRPC after ARPI and taxane therapy.
PSMAfore / FDA 2025 expansionPre-taxane PSMA+ mCRPC after ARPILu-177-PSMA-617 improved rPFS and FDA indication expanded to patients appropriate to delay taxane chemotherapy.
ASTRO Brain Metastases GuidelineCNS palliationSRS for limited brain mets; HA-WBRT + memantine when WBRT is needed and safe; supportive care alone can be appropriate for poor prognosis.
DARTSimulation-free palliationDiagnostic CT-based planning can reduce time in center for selected simple palliative RT cases.