Indications and Patient Selection
| Category | Criteria |
|---|---|
| Ideal (BCLC 0/A) | Single HCC ≤3 cm (optimal ≤2 cm) · Up to 3 nodules ≤3 cm · Child-Pugh A or B7 · ECOG PS 0–1 · Bridge to transplant while on waitlist · Recurrent HCC post-resection if accessible |
| Relative (tumor board) | 3–5 cm HCC: combination ablation + TACE (TACE-ablation); MWA preferred for larger tumors · Subphrenic/perivascular HCC: hydrodissection required · Residual viable HCC after TACE (LR-TR Viable on follow-up MRI) |
| Contraindicated | Child-Pugh C · Uncorrectable coagulopathy (INR >1.5 — correct; platelets <50K — transfuse) · Tumor adjacent to hepatic duct confluence (biliary stricture risk — surgery preferred) · Extrahepatic disease (curative intent) |
Ablation Modality Selection
| Modality | Best For | Key Limitation |
|---|---|---|
| Microwave (MWA) | Most HCC <5 cm; near vasculature (less heat-sink than RFA); two-probe simultaneous technique for 3–5 cm lesions | Tip artifact; larger ablation zone harder to predict precisely |
| RFA | Well-circumscribed HCC <3 cm, away from large vessels (>3 mm) | Heat-sink effect near portal/hepatic veins reduces zone size; slower than MWA |
| Cryoablation | Subphrenic lesions, perivascular, near bile ducts — iceball edge is visible on CT in real time | Longer procedure; cryoshock risk (rare); Segment VIII (IVC/RHV junction) preferred |
Perivascular HCC: Prefer MWA — less heat-sink effect than RFA. Reposition probe toward the portal side of the tumor to achieve margin despite heat dissipation. Segment VIII near IVC: Use cryoablation — the visible iceball avoids inadvertent IVC thermal injury not detectable with MWA/RFA.
Pre-Procedure Checklist
- Diagnostic MRI liver: LI-RADS LR-4 or LR-5 preferred — confirm arterial phase enhancement + washout.
- CT/PET-CT: Exclude extrahepatic disease for curative-intent ablation
- Measure tumor in 3 planes: Plan probe trajectory for 1 cm circumferential margin; for tumors >2.5 cm, plan overlapping zones ("tiling") with multiple probe positions before starting
- Labs: CBC, CMP, PT/INR, type and screen; AFP for baseline; HBV/HCV viral load — active HBV → prophylactic entecavir pre-procedure
- Coagulopathy correction: INR ≤1.5 (FFP if needed), platelets ≥50K (transfuse if needed)
- Anesthesia plan: MAC preferred for breath-hold compliance; general anesthesia for subphrenic lesions requiring controlled apnea
- D5W available for hydrodissection if bile ducts, bowel, or diaphragm within 1 cm of planned zone — D5W only (NOT saline — saline conducts electricity)
- Bilioenteric anatomy: If prior Whipple or biliary enteric anastomosis — prophylactic antibiotics (pip-tazo) required before ablation; higher abscess risk
Procedure Overview
The following is a high-level summary. Full probe and antenna selection by lesion size, multi-probe MWA strategies, hydrodissection protocols, and margin assessment criteria are available in RadCall Pro.
Setup and Positioning
Supine (most HCC) or left lateral decubitus (posterior right lobe). Unenhanced planning CT confirms lesion position and trajectory — avoid gallbladder, bowel, bile ducts, and diaphragm. Insert probe under apneic conditions with intermittent CT fluoroscopy.
Probe Placement and Ablation
Final CT confirms probe tip centered in or at the deep margin of the tumor. Traverse normal liver parenchyma to reach tumor — reduces capsular bleeding risk for subcapsular lesions. Two-probe simultaneous MWA for 3–5 cm lesions creates a larger confluent ablation zone with additive synergy beyond sequential ablation.
Hydrodissection
If bile ducts, bowel, or diaphragm are within 1 cm of the planned ablation zone: inject D5W into the targeted dissection plane and confirm separation on CT. Maintain a continuous slow D5W drip during ablation. D5W only — saline conducts electricity and can cause injury.
Intraprocedural Assessment and Tract Ablation
CT after ablation: zone must encompass tumor + ≥5 mm margin in all directions. If margin is inadequate, reposition and ablate before withdrawal. Activate probe during removal to ablate the tract (MWA/RFA) — reduces seeding risk.
LI-RADS Treatment Response (LR-TR)
Obtain MRI liver with gadolinium at 4–6 weeks post-ablation (allow edema to resolve). Use LI-RADS TR categories — not RECIST 1.1 (which underestimates response by relying on size alone):
| LR-TR Category | Imaging Findings | Action |
|---|---|---|
| LR-TR Nonviable | No arterial phase hyperenhancement (APHE); no washout; complete treatment zone | Routine surveillance MRI at 3–6 months |
| LR-TR Equivocal | Equivocal findings; may represent post-treatment change | Short-interval follow-up MRI at 3 months; consider biopsy if persistent |
| LR-TR Viable | APHE in untreated portion; washout; nodule in or at margin of treatment zone | Re-ablation if feasible; TACE bridge if >3 cm; multidisciplinary review |
| LR-TR Non-evaluable | Technically inadequate exam (motion, metal artifact, poor enhancement) | Repeat with adequate technique |
Complications
| Complication | Rate/Context | Management |
|---|---|---|
| Post-ablation syndrome | Common — fever, malaise, RUQ pain × 3–7 days | Self-limiting; Tylenol + NSAIDs; reassurance; persistent fever >72h → CT to rule out abscess |
| Hepatic abscess | 1–2%; higher with bilioenteric anatomy | CT-guided drain + broad-spectrum antibiotics; higher threshold for ERCP in post-Whipple patients |
| Hemorrhage | <2% significant | Subcapsular hematoma: serial CT; active extravasation → emergent hepatic arteriography + embolization |
| Pneumothorax | Subphrenic/intercostal access | Small, asymptomatic: O2 + observation. Moderate/large: CT-guided pigtail catheter |
| Biliary injury/biloma | Duct proximity — risk with hilar lesions | ERCP ± biliary stent for bile leak; hepatobiliary surgery for hilum stricture |
| Incomplete ablation | 10–30% (size/location-dependent) | LR-TR Viable on follow-up MRI → re-ablation or TACE; tumor board review |
Post-Procedure Care
- Day 0: 4h bedrest; vitals q30 min × 4h; CBC at 4h (hematocrit drop >6 = significant hemorrhage → repeat CT); pain management with Toradol + Tylenol scheduled; opioids PRN
- Post-ablation fever: Temperature >38°C is expected — Tylenol and reassurance. Persistent >72h → CT to rule out abscess
- Discharge: Same-day for single-lesion in Child-Pugh A; overnight for Child-Pugh B or complex cases
- AFP tracking: Baseline and at 4–6 weeks post-ablation. Rising AFP at follow-up → likely residual/recurrent HCC before imaging detects it
Imaging Follow-up Schedule
| Timepoint | Study | Assessment |
|---|---|---|
| 4–6 weeks | MRI liver with gadolinium | LR-TR response category (primary treatment response assessment) |
| 3 months | MRI liver | Early recurrence detection; AFP trend |
| 6 months | MRI liver | Surveillance; new lesions |
| 12 months | MRI + AFP | Annual thereafter; transplant candidacy reassessment |
Evidence Base for Liver-Directed Therapy in HCC
The evidence informing the choice of locoregional therapy in HCC spans multiple RCTs, meta-analyses, and registry studies. The following is an organized summary by modality, relevant when counseling patients or participating in multidisciplinary tumor board discussions.
1. TACE vs. Best Supportive Care — Foundational Evidence
TACE became the standard of care for intermediate-stage (BCLC B) HCC based on two landmark RCTs (Llovet 2002, Lo 2002) and a subsequent meta-analysis demonstrating improved overall survival compared with best supportive care. A systematic review of 101 studies (12,372 patients) reported an ORR of 52.5% and median survival of 19.4 months with conventional TACE. Median OS with TACE ranges from 16–40 months depending on patient selection. The NCCN and AASLD guidelines both endorse TACE as a primary locoregional option for unresectable HCC.[1,2,4]
2. cTACE vs. DEB-TACE vs. Bland Embolization (TAE)
- PRECISION V trial (212 patients, advanced HCC): DEB-TACE showed higher rates of complete response, objective response, and disease control vs. conventional TACE, but was not statistically superior (P = .11). Doxorubicin-related side effects were higher with conventional TACE.[3]
- Multiple RCTs and meta-analyses have shown similar responses and safety profiles between cTACE and DEB-TACE, with no consistent superiority of either approach.[2]
- A meta-analysis of RCTs comparing TACE (both types) to bland TAE also did not demonstrate superiority of chemoembolization over bland embolization — the embolic effect itself may be the primary mechanism.[3,5]
3. TARE — Y-90 Radioembolization
| Trial | Design | Key Result |
|---|---|---|
| LEGACY[6] | Single-arm, 162 pts, CTP-A, solitary HCC ≤8 cm | ORR 88.3% (mRECIST); DoR ≥6 mo in 76.1%; 3-yr OS 86.6% with radiation segmentectomy approach → FDA approval of Y-90 glass microspheres (2021) |
| TRACE[7] | Phase II RCT, 72 pts, BCLC A–B; Y-90 glass vs. DEB-TACE | TARE: TTP 17.1 vs. 9.5 mo (HR 0.36); OS 30.2 vs. 15.6 mo (HR 0.48). Trial terminated early after meeting primary endpoint |
| SARAH[8] | Phase III RCT, 459 pts, advanced HCC; Y-90 resin vs. sorafenib | No significant OS difference (8.0 vs. 9.9 mo; HR 0.86, P = .18). Post-hoc: patients receiving ≥100 Gy had OS 14.1 vs. 6.1 mo — dosimetry matters |
| DOSISPHERE-01[9] | RCT; personalized dosimetry (>205 Gy to tumor) vs. standard dosimetry | Personalized: ORR 76.6% vs. 22.2%; downstaging to surgery 35% vs. 3.5%; OS 26.6 vs. 10.7 mo. Dosimetry optimization is critical |
4. TARE as Bridge to Transplant
- UNOS database study (5,677 patients, 2026): TARE as first locoregional therapy was associated with a 22% decreased hazard of waitlist dropout vs. TACE (HR 0.78), higher complete necrosis on explant (35.3% vs. 20.2%), and fewer treatment sessions required.[10]
- Meta-analysis (10,661 patients, 2026): TARE required fewer sessions, had lower grade 3/4 bilirubin toxicity, higher complete necrosis rates, and superior recurrence-free survival compared to TACE for bridging and downstaging.[11]
5. Ablation (RFA/MWA) vs. Resection
| Study | Design | Finding |
|---|---|---|
| SURF trial[12] | Phase III RCT, 302 pts, Japan, HCC ≤3 cm; surgery vs. RFA | No significant difference in 5-yr OS (74.6% vs. 70.4%; HR 0.96) or RFS (42.9% vs. 42.7%). 90% solitary tumor, ~65% ≤2 cm |
| 2026 meta-analysis[13] | 25 studies, 10,322 patients | Resection: superior 3- and 5-yr OS and RFS overall; for tumors ≤2 cm, outcomes comparable between modalities |
The AASLD recommends an ablation-first strategy may be considered for tumors <3 cm with good hepatic reserve, particularly in patients with significant surgical risk.[2]
6. Radiation Therapy and HAIC vs. TACE
A 2024 systematic review of 40 RCTs (11,576 patients) established a hierarchical efficacy structure for locoregional therapies:[14]
Efficacy hierarchy (PFS and OS, network meta-analysis):
Surgery + adjuvant therapy > surgery alone > RT ≈ HAIC > TACE ≈ TARE ≈ TAE ≈ TKI monotherapy
RT vs. TACE: HR 0.35 (PFS and OS). HAIC vs. TACE: HR 0.57 (PFS), 0.58 (OS).
7. TACE + Systemic Therapy Combinations
| Trial | Regimen | Result |
|---|---|---|
| EMERALD-1[15] | TACE + durvalumab ± bevacizumab vs. TACE + placebo (phase III RCT) | Improved PFS vs. TACE + placebo — first positive phase III trial of immunotherapy combined with TACE |
| CHANCE2005/CARES-005[16] | TACE + camrelizumab + rivoceranib vs. TACE alone (phase II RCT, 200 pts) | PFS 10.8 vs. 3.2 mo (HR 0.34) — significant benefit with dual systemic blockade added to TACE |
Key takeaways for MDT discussion: No single modality is universally preferred (NCCN). Critical emerging themes: personalized dosimetry for TARE (DOSISPHERE-01); TARE over TACE for bridge-to-transplant (UNOS 2026); ablation appropriate for tumors <3 cm with good hepatic reserve; and combined locoregional + immunotherapy as the new frontier (EMERALD-1, CHANCE2005).
References
- Villanueva A. Hepatocellular Carcinoma. N Engl J Med. 2019;380(15):1450–1462.
- Singal AG, Llovet JM, Yarchoan M, et al. AASLD Practice Guidance on Prevention, Diagnosis, and Treatment of Hepatocellular Carcinoma. Hepatology. 2023;78(6):1922–1965.
- Katsanos K, Kitrou P, Spiliopoulos S, et al. Comparative Effectiveness of Different Transarterial Embolization Therapies for Unresectable HCC: A Network Meta-Analysis. PloS One. 2017;12(9):e0184597.
- National Comprehensive Cancer Network. Hepatocellular Carcinoma. Updated 2026-03-10.
- Thornton LM, Abi-Jaoudeh N, Lim HJ, et al. Combination and Optimal Sequencing of Systemic and Locoregional Therapies in HCC. J Vasc Interv Radiol. 2024;35(6):818–824.
- Salem R, Johnson GE, Kim E, et al. Yttrium-90 Radioembolization for the Treatment of Solitary, Unresectable HCC: The LEGACY Study. Hepatology. 2021;74(5):2342–2352.
- Dhondt E, Lambert B, Hermie L, et al. Y-90 Radioembolization Versus Drug-Eluting Bead Chemoembolization for Unresectable HCC: Results From the TRACE Phase II RCT. Radiology. 2022;303(3):699–710.
- Vilgrain V, Pereira H, Assenat E, et al. Efficacy and Safety of Selective Internal Radiotherapy With Y-90 Resin Microspheres Compared With Sorafenib in Locally Advanced HCC (SARAH). Lancet Oncol. 2017;18(12):1624–1636.
- Garin E, Tselikas L, Guiu B, et al. Personalised Versus Standard Dosimetry Approach of Selective Internal Radiation Therapy in Patients With Locally Advanced HCC (DOSISPHERE-01). Lancet Gastroenterol Hepatol. 2021;6(1):17–29.
- Kim NG, Yao FY, Kwong AJ, Mehta N. Y-90 Radioembolization Is Associated With a Lower Risk of Liver Transplant Waitlist Dropout Than Chemoembolization in HCC. J Hepatol. 2026;S0168-8278(26)00020-6.
- Xie M, Zhen Y. Efficacy of TARE and TACE as Downstaging or Bridging Strategies for HCC Before Liver Transplantation. Cardiovasc Intervent Radiol. 2026.
- Kawaguchi Y, Hasegawa K, Kashiwabara K, et al. Surgery Versus Ablation for HCC: SURF-RCT Trial. J Clin Oncol. 2025;JCO2402030.
- Dai LA, Sun M, Li T, Wei D, Zou RC. Comparison of Surgical Resection and RFA for Small HCC (≤3 cm): An Updated Meta-Analysis. Syst Rev. 2026.
- Patel KR, Menon H, Patel RR, et al. Locoregional Therapies for HCC: A Systematic Review and Meta-Analysis. JAMA Netw Open. 2024;7(11):e2447995.
- Sangro B, Kudo M, Erinjeri JP, et al. Durvalumab With or Without Bevacizumab With TACE in HCC (EMERALD-1). Lancet. 2025;405(10474):216–232.
- Zhu HD, Fan WJ, Zhao C, et al. TACE Combined With Camrelizumab and Rivoceranib for Unresectable HCC (CHANCE2005/CARES-005). J Clin Oncol. 2026;44(11):959–969.