Tumor biology plays a vital role in shaping interventional embolization strategies. Tumors exhibit diverse vascular patterns, and understanding these differences is crucial for effective treatment. Hypervascular tumors, such as renal angiomyolipoma (AML), respond well to embolization, with tumor shrinkage rates correlating with baseline size and vascular density (35, 36). Mechanistically, high vascular density increases the delivery of embolic agents to the tumor site, enhancing ischemia-induced necrosis. Conversely, hypovascular tumors may require adjunctive strategies such as radioembolization or systemic therapy to overcome limited perfusion-mediated drug delivery. Lin et al. (35) demonstrated that AMLs diameter >4 cm and high intratumoral vascularity predicted significant post-embolization volume reduction (OR: 3.2, p < 0.01). Conversely, hypovascular metastases (e.g., colorectal liver metastases) may require combination therapies like radioembolization with Yttrium-90 to enhance efficacy (37). Notably, NETs exhibit heterogeneous vascular patterns; Bai et al. (38) found that embolization outcomes varied significantly between NETs subtypes, with pancreatic NETs showing better response than gastrointestinal counterparts (HR: 1.8, p = 0.03). This biological heterogeneity underscores the need for pre-procedural imaging biomarkers (e.g., perfusion CT, DCE-MRI) to quantify vascularity and predict embolic agent distribution, enabling a mechanistically informed selection of embolization strategy. While tumor size and vascularity are consistently identified as predictors (35, 36), discrepancies exist in thresholds for “high-risk” tumor size (e.g., 4 cm vs. 5 cm), likely due to differences in embolic agents and follow-up durations. Future studies should standardize vascularity assessment using quantitative imaging biomarkers.

Patient-specific factors also significantly impact the feasibility and safety of embolization. Patient age, comorbidities, and functional status must be carefully evaluated. Arslan and Degirmencioglu (39) identified age >65 years, Child-Pugh B/C cirrhosis, and hypoalbuminemia as independent risk factors for post-embolization syndrome after TACE (AUC: 0.76). From a mechanistic perspective, hypoalbuminemia reflects reduced hepatic synthetic function and increased systemic inflammation, which may impair post-embolization recovery and increase susceptibility to infection or hepatic decompensation. Similarly, patients with ECOG ≥2 often have reduced systemic reserve, limiting their ability to tolerate procedural stress or post-embolization inflammation. Similarly, Kim et al. (40) reported higher complication rates in bladder cancer patients with ECOG ≥2 undergoing superselective vesical artery embolization (OR: 4.1, p < 0.001). Conversely, Hongyo et al. (36) emphasized that renal function preservation in AML patients favored selective embolization over surgery, particularly for those with chronic kidney disease (eGFR <60 mL/min/1.73 m²). The heterogeneity in comorbidity assessment complicates cross-study comparisons. Notably, while albumin-bilirubin (ALBI) grade predicts Yttrium-90 radioembolization survival in metastatic liver tumors, its utility in non-hepatocellular malignancies remains underexplored.

Embolization technique and material selection are pivotal. Liu et al. (41) showed that superselective embolization minimizes non-target ischemia. They combined radiofrequency ablation with embolization for renal AMLs and achieved 92% tumor control with preserved renal function. Mechanistically, superselective catheterization enables targeted delivery of embolic agents to the tumor-feeding vessels while preserving adjacent normal tissue perfusion. This reduces the risk of post-embolization syndrome and organ dysfunction, particularly in patients with limited functional reserve. For gastrointestinal hemorrhage, Xu et al. (42) demonstrated superior hemostasis with Fuaile adhesive compared to gelatin sponge (success rate: 94% vs. 78%, p = 0.02). Emerging approaches, like sequential embolization-cryoablation-osteoplasty for osseous tumors, highlight the role of multimodal strategies in complex cases (43).

Despite advances, embolic agent selection remains contentious. Crawford et al. (44) noted no significant difference in benign liver tumor outcomes between particles and lipiodol-based regimens, suggesting agent choice should align with operator expertise. However, particle size impacts distal penetration; smaller particles (<100 μm) may increase PES risk4, necessitating personalized sizing. Importantly, the interaction between particle size and vascular resistance is a key determinant of embolic distribution. Smaller particles penetrate deeper into the tumor microvasculature but may also pass into collateral or shunt vessels, increasing the risk of non-target embolization. Thus, a mechanistic understanding of tumor hemodynamics (e.g., arteriovenous shunting, pressure gradients) is essential for safe and effective agent selection.

Imaging biomarkers and post-procedural monitoring enhance outcome prediction. Tsai et al. (45) developed a cone-beam CT-based lipiodol deposition scoring system to predict 1-year HCC response post-TACE (AUC: 0.88). Similarly, Azar et al. (37) validated ALBI grade as a prognostic marker for Yttrium-90 radioembolization in non-HCC liver malignancies (median OS: 15.2 vs. 8.1 months for ALBI grade 1 vs. 2, p = 0.004). This supports the hypothesis that hepatic reserve influences not only treatment tolerance but also the regenerative response to embolization-induced injury. Patients with poor liver function may have impaired compensatory regeneration, leading to worse outcomes even after technically successful procedures. While imaging biomarkers show promise, their reproducibility across centers is limited by variability in imaging protocols. Standardization efforts, such as the Quantitative Imaging Biomarkers Alliance guidelines, are essential for clinical adoption.

Personalized embolization strategies hinge on integrating tumor biology, patient physiology, technical precision, and predictive analytics. While consensus exists on factors like tumor vascularity and comorbidities, variability in study designs and outcome measures underscores the need for standardized protocols. Future research should prioritize prospective validation of biomarkers and comparative effectiveness studies to refine decision-making frameworks.

The pre-treatment evaluation phase is critical for establishing a comprehensive baseline of both the patient and the tumor. Imaging examinations such as computed tomography (CT) and magnetic resonance imaging (MRI) provide detailed anatomical information about the tumor, including its location, size, and vascular supply (46). CT angiography is particularly useful for visualizing the tumor’s blood supply and identifying potential feeding arteries (47). A study demonstrated that multi-phase CT imaging could accurately identify the vascular characteristics of hepatocellular carcinoma, guiding the selection of embolization techniques and embolic agents (21).

Laboratory tests are equally important. Liver function tests, such as albumin and bilirubin levels, help assess the patient’s ability to tolerate the procedure and the potential for post-embolization complications (48). For example, patients with Child-Pugh B cirrhosis may have a higher risk of liver failure following traditional TACE, making DEB-TACE a more suitable option (49). Similarly, renal function tests are essential for determining the patient’s ability to excrete contrast agents used during the procedure. Aoe et al. found that patients with impaired renal function had a higher incidence of contrast-induced nephropathy following TACE, highlighting the need for careful pre-treatment assessment (50).

Tumor biomarker assessments provide additional information about tumor activity and prognosis. Elevated levels of alpha-fetoprotein (AFP) in patients with HCC can indicate tumor burden and aggressiveness (51). He et al. showed that patients with high AFP levels often had poorer treatment outcomes following TACE, emphasizing the importance of incorporating biomarker data into treatment planning (52).

Based on the pre-treatment evaluation, a tailored treatment plan is developed. This includes selecting the most appropriate embolization technique and determining the optimal embolic agents and drug dosages (53). Conventional TACE involves mixing chemotherapeutic drugs with lipiodol and embolic agents, while DEB-TACE uses drug-eluting microspheres loaded with chemotherapeutic drugs (54). A meta-analysis by Wang et al. found that DEB-TACE demonstrated better radiological tumor response and progression-free survival compared to conventional TACE. This is likely due to the more controlled drug release and reduced systemic toxicity of DEB-TACE (55).

The choice of embolic agents also depends on the tumor’s vascular characteristics and the desired treatment outcome (56). Gelatin sponge particles are biodegradable and commonly used in conventional TACE, but their non-uniform particle size may lead to non-target embolization. Polyvinyl alcohol particles are non-biodegradable and provide long-term vessel occlusion, but their use may increase the risk of post-embolization syndrome (56). Microspheres, such as DEBs, offer controlled drug release and reduced systemic toxicity. A retrospective study showed that DEB-TACE using microspheres achieved better tumor response and survival outcomes compared to conventional TACE with gelatin sponge particles (57).

The intraoperative phase involves the implementation of the treatment plan. During the procedure, the interventional radiologist carefully navigates the catheter to the tumor-feeding arteries and administers the embolic agents according to the pre-determined plan. Real-time imaging, such as fluoroscopy and angiography, is used to monitor the progress of the procedure and ensure accurate delivery of the embolic agents (58). Intraoperative complications, such as vessel perforation or non-target embolization, must be promptly identified and managed. Studies have shown that the combined use of embolizing agents with different particle sizes can achieve more complete vascular occlusion and reduce the risk of complications (18, 59).

Short-term and long-term follow-up schedules are essential for monitoring treatment outcomes and complications. Short-term follow-up typically includes clinical assessments and imaging studies within the first few weeks to evaluate the immediate response to treatment and detect any complications (60). Scheau et al. (61) showed that early follow-up imaging could identify cases of incomplete tumor necrosis, allowing for timely re-treatment. Long-term follow-up involves regular monitoring of tumor recurrence and patient survival. Studies have demonstrated that patients receiving personalized embolization therapy often have improved survival rates and quality of life (62). For example, Garin et al. (63) found that personalized chemoembolization for HCC significantly improved patient survival rates compared to conventional treatment (Tables 1–4).

Personalized TACE has revolutionized HCC management. Gholamrezanezhad et al. (64) demonstrated that 70–150 μm DEBs achieved targeted drug delivery and reduced tumor growth in a rabbit VX2 liver tumor model, with histological confirmation of necrosis and minimal systemic toxicity. In clinical practice, Kim et al. (65) compared Yttrium-90 radioembolization with conventional TACE in a propensity score-matched study (n = 156), showing superior progression-free survival (11.2 vs. 6.8 months, p = 0.003) and fewer adverse events with Yttrium-90. However, Lee et al. (66) highlighted regional variations in TACE refractoriness definitions, emphasizing the need for standardized criteria. Emerging strategies include combining TACE with anti-angiogenic agents; Chen et al. (67) reported enhanced tumor response in rabbit VX2 models using apatinib-TACE combination therapy, validated by intravoxel incoherent motion MRI. While DEB-TACE and Yttrium-90 show efficacy, discrepancies exist in patient selection and embolic agent protocols. For instance, Sarwar et al. (68) advocated for resin microspheres in Yttrium-90 to optimize dosimetry, whereas Binzaqr et al. (69) observed improved outcomes in HCC patients post-SIRT after incomplete TACE response, suggesting sequential therapy benefits. These variations underscore the need for personalized protocols based on tumor vascularity and liver reserve.

Portal vein embolization (PVE) and hepatic vein embolization (HVE) are critical for resectability in colorectal cancer liver metastases (CRLM). Niekamp et al. (70) demonstrated that HVE after PVE induced additional liver hypertrophy (median 47% volume increase) in metastatic colorectal cancer patients, facilitating curative resection. Comparatively, Rassam et al. (71) found associating liver partition and portal vein ligation (ALPPS) superior to PVE in hypertrophy rates but with higher morbidity. For unresectable cases, Braat et al. (72) combined lutetium-177-DOTATATE with holmium-166 radioembolization in neuroendocrine liver metastases, achieving disease control in 75% of patients. PVE and ALPPS differ in risk–benefit profiles, necessitating individualized planning. While ALPPS offers rapid hypertrophy, its morbidity limits use in frail patients. Radioembolization combinations (e.g., holmium-166) show promise but require validation in larger cohorts.

Embolization plays a role in managing bleeding and unresectable pancreatic tumors. Tokue et al. (73) successfully controlled life-threatening hemorrhage in intraductal papillary mucinous neoplasms using coil embolization. For advanced disease, Lopez-Benitez et al. (74) developed gemcitabine-eluting hydrogel devices, demonstrating sustained drug release and tumor suppression in murine models. Kook et al. (75) reported laparoscopic pancreaticoduodenectomy with preoperative embolization of aberrant hepatic arteries, reducing intraoperative bleeding in mid-bile duct cancer. While embolization effectively manages hemorrhage, therapeutic applications (e.g., drug-eluting hydrogels) remain experimental. Heterogeneity in pancreatic tumor biology complicates standardized protocols, necessitating biomarker-driven approaches.

Liver-dominant NETs metastases benefit from radioembolization and multimodal approaches. Maekawa et al. (76) introduced hormonal tumor mapping to guide embolization of gastroenteropancreaticNETs liver metastases, achieving 68% partial response rates. Drescher et al. (77) combined holmium-166 TARE with systemic therapy, reporting median progression-free survival of 14.3 months in a multicenter study. In contrast, Bibok et al. (78) observed modest efficacy of radioembolization in RCC liver metastases, emphasizing histology-specific responses. NETs heterogeneity demands subtype-specific strategies. While holmium-166 shows promise, its utility in non-NET metastases is limited, highlighting the importance of molecular profiling.

Personalized embolization strategies improve outcomes across digestive tumors by integrating tumor biology, vascular anatomy, and patient-specific factors. While HCC and CRLM have robust evidence, pancreatic and NETs applications require further refinement. Discrepancies in study designs (e.g., DEB-TACE vs. Yttrium-90) highlight the need for comparative trials. Future directions include biomarker-driven protocols and advanced embolic materials to optimize therapeutic precision.

Personalized peripheral vascular interventional embolization has emerged as a critical strategy for managing urinary system tumors, particularly in cases where surgical resection is contraindicated or for palliative care. This section synthesizes evidence from recent studies, focusing on renal AML, RCC, bladder cancer, and prostate cancer, while evaluating the consistency and limitations of current research.

AML, a benign tumor composed of fat, smooth muscle, and blood vessels, often requires embolization to manage hemorrhage or reduce tumor burden. A landmark prospective randomized study by Wang et al. (79) compared polyvinyl alcohol (PVA) particles versus a combination of lipiodol-bleomycin emulsion (LBE) and NBCA-lipiodol emulsion for AML embolization. The LBE-NBCA group demonstrated superior outcomes, including higher rates of complete remission (CR, 93.8% vs. 68% in PVA) and reduced need for repeat embolization, attributed to enhanced vascular occlusion and tumor necrosis. These findings underscore the importance of tailored embolic agent selection based on tumor vascularity and clinical presentation. For acute scenarios, urgent embolization of ruptured AML achieves rapid hemostasis. Kervancioglu and Yilmaz (80) reported immediate symptom resolution in 95% of cases, with no major complications, highlighting its role in emergency management. However, long-term follow-up data remain limited, necessitating further studies to validate durability.

In locally advanced RCC, embolization is often combined with surgical or ablative therapies. Uka et al. (81) demonstrated that preoperative embolization followed by percutaneous cryoablation achieved 85% local tumor control in T3a RCC with venous involvement, minimizing intraoperative bleeding and enhancing procedural safety. Similarly, Lopez et al. (82) utilized NBCA embolization prior to cryoablation, achieving 92% technical success with no major adverse events, suggesting synergistic benefits in tumor devascularization. Selective embolization also plays a role in managing unresectable RCC. Aydin et al. (83) employed upper-body perfusion techniques during tumor thrombectomy, reducing systemic complications and improving survival in patients with vena cava involvement. These studies emphasize the need for individualized approaches based on tumor stage and vascular anatomy.

For advanced bladder cancer with intractable hematuria, selective transarterial embolization (TAE) offers effective palliation. Hekimoglu et al. (84) reported a 78% success rate in controlling hemorrhage, with minimal procedural morbidity, in patients unfit for surgery. Notably, tumor size and vascularity influenced outcomes, with larger tumors requiring higher embolic doses. While these results align with earlier studies, heterogeneity in embolic agents (e.g., gelatin sponge vs. coils) across trials complicates direct comparisons, underscoring the need for standardized protocols.

Prostate artery embolization (PAE) has gained traction for palliative management of localized prostate cancer. Malling et al. (85) observed significant symptom relief in 80% of patients with hormone-refractory disease, with reduced urinary obstruction and improved quality of life. A follow-up feasibility study by the same group proposed CT perfusion as a predictor of PAE response, identifying tumor perfusion metrics as key determinants of success (86). However, small sample sizes and single-center designs limit generalizability, warranting multicenter validation.

Current evidence supports the efficacy of personalized embolization across urinary tumors, yet inconsistencies persist. For AML, while LBE-NBCA combinations outperform PVA 10, cost and availability may limit adoption in resource-constrained settings. In RCC, combined embolization-ablation strategies show promise, but long-term oncologic outcomes remain understudied. For bladder and prostate cancers, standardization of embolic agents and dosages is crucial to enhance reproducibility. Future research should prioritize randomized trials comparing embolic materials, integrate biomarkers for response prediction, and explore combination therapies with immunotherapy or targeted agents. Such efforts will refine personalization paradigms and solidify embolization’s role in multidisciplinary tumor management.

Personalized peripheral vascular interventional embolization has demonstrated efficacy in managing a diverse range of tumors beyond the urinary and digestive systems. This section evaluates its role inNETs, spinal and soft tissue neoplasms, carotid body tumors, and other rare malignancies, focusing on clinical outcomes, technical nuances, and areas requiring further standardization.