Treatment of Irresectable Colorectal Liver Metastases by Combination of Liver Resection and Percutaneous Tumor Ablation: Mid-term Outcome

Abstract

Purpose

Primary resection of liver metastases in colorectal cancer remains the leading curative approach. However, a small future liver remnant or central localization of metastases often prevent resectability. In such cases, combining resection with percutaneous ablation may offer a curative-intent treatment option. This study aims to evaluate the oncologic results and morbidity of this combined treatment.

Materials and methods

In this retrospective study, 21 patients with advanced colorectal liver metastases underwent a two-stage treatment consisting of planned incomplete resection and percutaneous ablation. Outcomes assessed included overall survival and intrahepatic progression-free survival. Main exclusion criteria were extrahepatic disease and ablation of metastases > 3 cm. Results are reported as medians with 95% confidence intervals and standard deviation.

Results

The median number of preoperative intrahepatic metastases was 5 [2–13]. Follow-up was available for 95% of patients, with a median follow-up of 21 months. Intra- und extrahepatic recurrences occurred in 81% (17/21). Median intrahepatic progression-free survival was 5 [0–44] months. Median overall survival was 36.5 [6.6–55] months, resulting in a 1-year survival rate of 91%. Twelve patients (57%) passed away. Technical success was achieved in 90%. Three major complications occurred, all of which were successfully treated.

Conclusion

In patients with partially unresectable colorectal liver metastases, a two-stage approach combining resection and percutaneous ablation represents a potential curative-intent strategy, particularly when intraoperative ablation is not feasible. Despite high recurrence rates, OS was comparatively long relative to systemic therapy. Further studies are needed to explore treatment sequencing, perioperative therapies, and advanced ablation technologies for optimizing the concept. Ultimately, treatment must be individualized based on the patient’s disease profile and institutional capabilities.

Key Points

• A two-stage approach combining resection and percutaneous ablation represents a potential curative-intent strategy in partially irresectable colorectal liver metastases.

• High recurrence rates occur, but overall survival remains comparatively long.

• Individualized, interdisciplinary treatment planning optimizes patient outcomes.

• Further research is needed on sequencing, perioperative strategies, and ablation technologies.

Citation Format

• Lokancevic T, Keil S, Bruners P et al. Treatment of Irresectable Colorectal Liver Metastases by Combination of Liver Resection and Percutaneous Tumor Ablation: Mid-term Outcome. Rofo 2026; DOI 10.1055/a-2781-8926

Zusammenfassung

Ziel

Die Resektion von Lebermetastasen bei kolorektalem Karzinom bleibt der Goldstandard als kurative Therapieoption. Ein kleines Leberrestvolumen oder eine zentrale Lage der Metastasen verhindern jedoch häufig die Resektabilität. In solchen Fällen kann die Kombination von Resektion und perkutaner Ablation eine Therapieoption in kurativer Intention darstellen. Ziel dieser Studie war es, das Überleben, die Rezidivraten und die Morbidität dieser kombinierten Behandlung zu untersuchen.

Material und Methoden

In dieser retrospektiven Studie erhielten 21 Patienten mit fortgeschrittenen kolorektalen Lebermetastasen eine zweistufige Behandlung, bestehend aus geplanter inkompletter Resektion und perkutaner Ablation. Erhobene Endpunkte waren das Gesamtüberleben und das intrahepatische progressionsfreie Überleben. Hauptausschlusskriterien waren extrahepatische Tumormanifestationen und Metastasen >3 cm. Ergebnisse werden als Median mit 95%-Konfidenzintervallen und Standardabweichung berichtet.

Ergebnisse

Der Median der Anzahl präoperativer intrahepatischer Metastasen betrug 5 [2–13]. Follow-up-Daten lagen für 95% der Patienten vor, mit einem medianen Follow-up von 21 Monaten. Rezidive traten bei 81% (17/21) der Patienten auf. Das mediane intrahepatische progressionsfreie Überleben betrug 5 [0–44] Monate. Das mediane Gesamtüberleben lag bei 36,5 [6,6–55] Monaten. Dies entspricht einer 1-Jahres-Überlebensrate von 91%. Zwölf Patienten (57%) verstarben während des Untersuchungszeitraumes.

Die technische Erfolgsrate lag bei 90%. Es traten drei Komplikationen auf, die jedoch alle erfolgreich behandelt werden konnten.

Schlussfolgerung

Bei Patienten mit partiell irresektablen kolorektalen Lebermetastasen stellt eine Kombinationstherapie aus Resektion und perkutaner Ablation eine in kurativer Intention durchgeführte Therapieoption dar, insbesondere wenn eine intraoperative Ablation nicht durchführbar ist. Trotz hoher Rezidivraten zeigte sich ein vergleichsweise langes Gesamtüberleben im Vergleich zu systemischen Therapien.

Weitere Studien sollten den Einfluss von Therapiereihenfolge, perioperativen Zusatztherapien und technischen Weiterentwicklungen untersuchen.

Das Behandlungskonzept sollte letztlich individuell an das Krankheitsprofil des Patienten und die institutionellen Möglichkeiten angepasst werden.

Kernaussagen

• Die Kombination von Resektion und perkutaner Ablation von a priori irresektablen Metastasen bietet eine Therapiemöglichkeit in kurativer Intention.

• Es wurden hohe Rezidivraten beobachtet, aber das Gesamtüberleben ist vergleichsweise lang.

• Individualisierte, interdisziplinäre Behandlungsplanung optimiert Therapieergebnisse.

• Weitere Forschung zu Therapiereihenfolge, perioperativen Strategien und Ablationstechniken ist notwendig.

Keywords

ablation procedures - interventional procedures - metastases - radiofrequency (RF) ablation - percutaneous - abdomen

Introduction

In Western countries, colorectal cancer (CRC) ranks as the second most common cause of death due to malignancy. Approximately 50% of affected patients suffer from colorectal liver metastases (CRLM), which significantly reduces overall survival (OS). Untreated, disseminated CRLM have a median OS of less than one year [1] [2].

While resection remains the gold standard for curative therapy of CRLM, only about 10–20% of patients present with resectable disease [3] [4]. Additional local treatment strategies could therefore be considered to potentially expand curative options. In this context, minimally invasive ablation is gaining importance, particularly for smaller metastases ≤ 2 cm, where it has demonstrated outcomes comparable to resection [5]. As ablation becomes increasingly available in cancer centers, an interdisciplinary treatment approach for CRLM is essential.

Although numerous studies assess overall survival after either resection or ablation of CRLM [6], fewer investigate the combined approach for oligometastatic disease to extend curative options. Previous research has reported outcomes following surgical resection combined with intraoperative RFA or MWA [7] [8] [9] [10] [11]. Nevertheless, intraoperative thermoablation is not always feasible and may be limited by challenges in intraoperative detection and by anatomically complex intrahepatic locations. In our institutional experience, feasibility for intraoperative ablation is limited by the need for coordinated availability of surgical and radiological teams, as well as by the inability to detect some lesions sonographically. Radiologists can localize such lesions using cross-sectional imaging and provide the full spectrum of ablation modalities. Studies evaluating two-stage treatment combining incomplete resection with percutaneous ablation are scarce.

This study aims to evaluate overall survival and the intrahepatic recurrence rate following combined resection and percutaneous ablation in patients with otherwise unresectable CRLM, who are treated with curative intent.

Materials and Methods

Patients and data collection

We retrospectively screened 136 electronic records of patients who underwent ablation between March 2014 and July 2020. Eligibility was restricted to patients with multifocal, partially unresectable CRLM. Inclusion and exclusion criteria are summarized in [Fig. 1]. Twenty-one patients were included in the statistical analysis. In all cases, complete tumor clearance would not have been achievable without combining resection and percutaneous ablation.

Fig. 1 Inclusion and exclusion criteria.

All patients underwent staging via full-body CT alone or in combination with liver MRI. Treatment plans were set by an interdisciplinary tumor board. Standard criteria for assessing resectability, such as number and location of CRLM, proximity to major hepatic vessels, liver function, and future liver remnant, were applied. Metastases eligible for resection were surgically removed. Lesions ≤ 3 cm that could not be resected were scheduled for percutaneous ablation. The total number of metastases was not an exclusion criterion. Absence of disease progression between the two treatment steps was verified in all patients by up-to-date cross-sectional imaging obtained shortly before liver resection or ablation.

Ablation was performed under CT guidance by experienced interventional radiologists. The choice of technique, RFA, MWA, or irreversible electroporation (IRE), was based on metastasis location and the radiologists’ experience. For RFA, a monopolar system (RF 3000, Boston Scientific Corp, MA, USA) with umbrella-shaped applicators with a 2–4 cm diameter and varying shaft lengths was used (LeVeen, Boston Scientific Corp, MA, USA). MWA was performed by using the Emprint system (Medtronic, MI, USA) using dedicated antennas with varying shaft lengths. The NanoKnife-System (AngioDynamics, Amsterdam, the Netherlands) was utilized for IRE with two to five probes with a tip exposure of 1.5 cm. IRE was performed with 70–90 pulses per probe pair, a pulse length of 90 µs, and a maximum voltage of 3,000 V. Ablation followed the manufacturer's protocols and was performed under general anesthesia. After ablation, a multiphase contrast-enhanced CT scan was performed to assess complications and ablation success. Re-ablation was performed if needed to ensure complete coverage. Track ablation was used in all RFA and MWA cases to prevent needle-track seeding.

Follow-up included contrast-enhanced CT or liver MRI (1.5 T Achieva, Philips) four weeks after ablation, then every three months for two years and thereafter every six months for up to five years.

Statistical analysis and outcome measures

Primary endpoints were overall survival (OS) and intrahepatic progression-free survival (ihPFS).

OS was defined as the time from therapy completion to death from any cause, and ihPFS as the time from completion of therapy to the first intrahepatic recurrence.

OS and ihPFS were estimated using Kaplan-Meier analysis. Patients with isolated extrahepatic progression were censored when it was detected. Results are presented as medians with 95% confidence intervals (CI) and standard deviation (SD). 1-year survival and follow-up rates were calculated. Patients with incomplete follow-up were censored at the date of their last documented contact.

Secondary endpoints included technical success and complication rates. Technical success was defined as complete ablation in the first follow-up after 4 weeks. Post-ablation and post-resection complications were described individually and categorized according to CIRSE criteria [12].

Patient demographics, number of metastases, Fong-Clinical Risk Score (CRS), Eastern Cooperative Oncology GroupScore (ECOGScore) as well as prior therapies, resection and ablation types were reported as counts and percentages, or medians with ranges.

Statistical analyses were performed using IBM SPSS Statistics 27.

Results

Twenty-one patients underwent combined resection and percutaneous ablation with curative intent. One patient with rectal cancer received a “liver-first” approach. The primary tumor was resected five months after liver treatment. All patients received guideline-adapted adjuvant chemotherapy after resection of the primary tumor.

The median number of CRLM before treatment was five [2–13]. Additional demographic data are available in [Table 1].

Table 1 Demographic variables.

Demographic variables	N (%)	Median [Range]
Sex
Male	17 (81)
Female	4 (19)
Age (years)		55 [33–79]
Metastases
Total		5 [2–13]
Ablated		2 [1–3]
CRS		3 [1–4]
ECOG-Score		1 [0–2]

Eleven patients (52.4%) had undergone previous liver resections. Six out of 21 patients received ablation before surgery. In 15 patients, surgery preceded ablation.

The median interval between resection and percutaneous ablation was 1.1 months [0.2–5], with no observed tumor progression during that period. Details on resection and ablation types, as well as therapy intervals, are shown in [Table 2].

Table 2 Previous therapies, resection and ablation types, interval between resection and ablation.

Therapy	N (%)
Previous surgeries	11 (52.4)
PVL (portal vein ligation)	7 (33.3)
Resection types
Right hemihepatectomy	6 (28.6)
Right hemihepatectomy + non-anatomical resection	1 (4.8)
Left-hemihepatectomy + non-anatomical resection	2 (9.5)
Non-anatomical resection	12 (57.1)
Ablation types
MWA	7 (33.3)
IRE	7 (33.3)
RFA	5 (23.8)
Intraoperative MWA + IRE	2 (9.5)
	Median [Range]
Interval between resection and ablation (months)	1.1 [0.2–5]

A follow-up rate of 95% was achieved, with a median follow-up of 21 months [7–55]. One patient (5%) discontinued follow-up prior to the study endpoint.

Technical success and complication rates

Technical success of the ablation procedures was achieved in 90% (19/21). Incomplete ablation occurred in two cases (10%, IRE with needle-track seeding).

Post-treatment complications were observed in 14%. Two were surgery-related (perihepatic abscess, bilioma) and were managed by CT-guided drainage. The third was a portal vein thrombosis, treated with anticoagulation and ascites drainage. All complications prolonged hospitalization, and are classified as major complications but were successfully treated.

Intrahepatic progression-free survival

Median ihPFS was 5 months ([0–44]; 95% CI [1.5; 7.5]; SD 1.3), [Fig. 2].

Fig. 2 Intrahepatic progression-free survival.

Tumor recurrence (intrahepatic or extrahepatic) occurred in 81% (17/21) of patients. Of these, 18% (3/17) recurred at the ablation site, 24% (4/17) at the resection site. About 41% (7/17) of patients had an intrahepatic recurrence at sites remote from the ablation or resection areas. The remaining 17% (3/17) of patients had extrahepatic disease.

Overall survival

Median OS was 36.5 months ([6.6–55]; 95% CI [33.6; 39.4]; SD 1.46), with a 1-year survival rate of 91% ([Fig. 3]).

Fig. 3 Overall survival.

At study end, 12 patients (57%) had died. Eight patients (38%) were alive at last follow-up. One patient (5%) was lost to follow-up.

Discussion

The aim of this study was to analyze the OS and ihPFS of patients with oligometastatic, partially unresectable CRLM who underwent a combination therapy of resection and percutaneous ablation to achieve tumor clearance. With a follow-up rate of 95%, we observed a median OS of 36.5 months and an ihPFS of 5 months.

For patients with a priori unresectable oligometastatic CRLM, palliative chemotherapy remains a primary alternative. Advances in systemic therapies, driven by improved understanding of tumor biology and targeted agents, have enabled downstaging and subsequent resectability in some cases. However, if downstaging is not achieved within two to four months, patients typically continue with guideline-based palliative chemotherapy. In this population, which is comparable to our cohort, reported OS ranges from 7–37 months depending on treatment regimen and tumor genetics [13] [14] [15]. In this context, the OS observed in our cohort is comparatively high.

Nevertheless, our median OS of 36.5 months lies at the lower end of the 36–50 months reported in comparable curative approaches [7] [9] [10] [16], but it may reflect outcomes seen in higher-risk cohorts. Approximately 52% of our patients had undergone previous liver surgery, and the median Fong-CRS was 3, indicating a cohort predisposed to a poorer outcome. Retrospective studies with comparable therapeutic strategies have shown that the number and size of metastases – key components of the Fong-CRS score – can significantly influence OS, ihPFS and complication rates [8] [9] [10].

With a 81% tumor recurrence rate, our results reflect a key limitation of ablation, particularly compared to resection, which continues to achieve lower local recurrence rates [6]. Although such a high rate may appear discouraging at first, it is important to recognize that many patients remain eligible for salvage therapy, such as repeat ablation or segmentectomy. In our study, eight out of 17 patients (47%) with recurrence underwent salvage treatment. This likely contributes to the relatively high OS, despite the short ihPFS, aligning with findings from a retrospective study on salvage therapy via ablation for CRLM [17].

Several aspects of the combined resection-ablation strategy may influence intrahepatic recurrence, including treatment sequencing, the interval between both interventions and underlying tumor biology. Evidence suggests that two-stage concepts may offer biological and technical advantages. Livraghi et al. investigated the “test-of-time” approach, in which definitive liver surgery was intentionally delayed, to allow biologically aggressive micrometastases to manifest before major hepatectomy is undertaken. Their findings showed no significant differences in OS and no loss of resectability [18]. Conversely, delaying surgery also carries the risk of interval progression, underscoring the need for structured imaging follow-up. Additional biological considerations for an ablation-first approach arise from experimental data indicating that the inflammatory response following hepatic surgery may stimulate residual tumor activity [19]. Whether inflammation after ablation has an effect on tumor growth remains unclear, but it represents a relevant biological factor that may influence recurrence patterns [20] [21]. The majority of previous studies have evaluated immediate intraoperative ablation combined with resection. However, specific surgical expertise and organizational coordination are not universally available. A retrospective study similar to ours compared an intraoperative ablation with postoperative percutaneous ablation group after incomplete resection and found significantly lower complication rates and a lower 5-year local tumor progression in the percutaneous group [22]. Although our cohort did not follow a predefined order of interventions, treatment sequencing may be an important conceptual aspect of two-stage strategies and could be considered in further investigations. The window between ablation and resection could also provide an opportunity for adjuvant strategies such as immunotherapy or anti-angiogenic agents [23]. Ablation-specific factors may also influence intrahepatic recurrence. Technical advancements, such as stereotactic-guided navigation or the combination of ablation and transarterial embolization, have the potential to improve targeting precision and further reduce recurrence rates [24] [25] [26].

Previous studies indicate that local treatment of CRLM prolongs OS [27] [28] [29]. Accordingly, techniques to maximize resectability, such as downstaging, portal vein embolization, and combination with ablation, are continually evolving. This reflects a broader trend toward increasingly aggressive curative-intent strategies, even in patients with extensive disease [30]. For example, a recent retrospective study found no significant difference in OS or ihPFS between patients undergoing resection alone versus those receiving combined resection and ablation [31].

Nevertheless, combining resection with ablation extends the current boundaries of curative therapies in CRLM. Establishing clear limits within these broader trends is challenging, particularly in determining which patients truly benefit. Pawlik et al. [7] reported that patients with more than ten liver metastases had a significantly shorter time to intrahepatic recurrence, suggesting that curative combined therapy in such cases should be considered critically. These uncertainties are compounded by the absence of randomized controlled trials, leaving most evidence based on retrospective analyses. The rationale for the combined treatment is individualized and influenced by patient-specific and institutional factors. This view is consistent with recent findings from the COLLISION trial. The authors conclude that thermal ablation should not be limited to unresectable cases, but rather incorporated into decision-making based on clinical context and available expertise [29].

Limitations

While the study’s small sample size and use of multiple ablation techniques, resulting in a heterogeneous cohort, are clear limitations of this study, the data nonetheless reflect real-world practice. In our institution, the expertise of interventional radiologists allows for the selection of the optimal ablation technique for each case. Treatment choice was individualized based on tumor size, location, technical feasibility, and operator experience.

Conclusions

In conclusion, for patients with partially unresectable colorectal liver metastases, a two-stage approach combining resection and percutaneous ablation represents a potential curative-intent strategy, particularly when intraoperative ablation is not feasible. Despite relatively high intrahepatic recurrence rates, this strategy may offer a survival benefit compared to systemic therapies, potentially due to salvage treatment. Further research is needed to assess the impact of treatment sequencing, perioperative therapies (e.g. immunotherapy, anti-angiogenics), and advanced technologies (e.g. stereotactic ablation, preoperative embolization). Ultimately, therapeutic concepts should be tailored to the patient’s individual disease profile and take into consideration institutional capabilities.

Clinical relevance

• In patients with colorectal liver oligometastases, the combination of resection with percutaneous ablation for primarily unresectable metastases may offer a curative-intent treatment option.

• Despite high intrahepatic recurrence rates, overall survival is high compared to systemic therapy alone, likely supported by the availability of salvage treatment.

• Individualized, interdisciplinary treatment planning and further research on sequencing, perioperative strategies, and technical innovations are essential to optimize outcomes.

Conflict of Interest

The authors declare that they have no conflict of interest.

• References

• 1 Bengtsson G, Carlsson G, Hafström L. et al. Natural history of patients with untreated liver metastases from colorectal cancer. Am J Surg 1981; 141: 586-589
• 2 Sung H, Ferlay J, Siegel RL. et al. Global Cancer Statistics 2020: GLOBOCAN Estimates of Incidence and Mortality Worldwide for 36 Cancers in 185 Countries. CA Cancer J Clin 2021; 71: 209-249
• 3 Stangl R, Altendorf-Hofmann A, Charnley RM. et al. Factors influencing the natural history of colorectal liver metastases. Lancet 1994; 343: 1405-1410
• 4 Penchev DK, Vladova LV, Zashev MZ. et al. Distant Liver Metastases as a Major Factor Influencing Survival in Patients with Colorectal Cancer. Folia Med (Plovdiv) 2016; 58: 182-187
• 5 Puijk RS, Dijkstra M, van den Bemd BAT. et al. Improved Outcomes of Thermal Ablation for Colorectal Liver Metastases: A 10-Year Analysis from the Prospective Amsterdam CORE Registry (AmCORE). Cardiovasc Intervent Radiol 2022; 45: 1074-1089
• 6 Kron P, Linecker M, Jones RP. et al. Ablation or Resection for Colorectal Liver Metastases? A Systematic Review of the Literature. Front Oncol 2019; 9: 1052
• 7 Pawlik TM, Izzo F, Cohen DS. et al. Combined Resection and Radiofrequency Ablation for Advanced Hepatic Malignancies: Results in 172 Patients. Ann Surg Oncol 2003; 10: 1059-1069
• 8 Kornprat P, Jarnagin W, DeMatteo R. et al. Role of intraoperative thermoablation combined with resection in the treatment of hepatic metastasis from colorectal cancer. Arch Surg 2007; 142: 1085-1092
• 9 Philips P, Groeschl RT, Hanna EM. et al. Single-stage resection and microwave ablation for bilobar colorectal liver metastases. Br J Surg 2016; 103: 1048-1054
• 10 Agcaoglu O, Aliyev S, Karabulut K. et al. Complementary Use of Resection and Radiofrequency Ablation for the Treatment of Colorectal Liver Metastases: An Analysis of 395 Patients. World J Surg 2013; 37: 1333-1339
• 11 Abdalla EK, Vauthey JN, Ellis LM. et al. Recurrence and outcomes following hepatic resection, radiofrequency ablation, and combined resection/ablation for colorectal liver metastases. Ann Surg 2004; 239: 818-825
• 12 Filippiadis DK, Binkert C, Pellerin O. et al. Cirse Quality Assurance Document and Standards for Classification of Complications: The Cirse Classification System. Cardiovasc Intervent Radiol 2017; 40: 1141-1146
• 13 Zheng P, Ren L, Feng Q. et al. Patients with RAS wild-type right-sided unresectable liver-confined mCRC also benefit from cetuximab plus chemotherapy in first-line treatment. Am J Cancer Res 2018; 8: 2337-2345
• 14 Loupakis F, Cremolini C, Masi G. et al. Initial therapy with FOLFOXIRI and bevacizumab for metastatic colorectal cancer. N Engl J Med 2014; 371: 1609-1618
• 15 Cremolini C, Loupakis F, Antoniotti C. et al. FOLFOXIRI plus bevacizumab versus FOLFIRI plus bevacizumab as first-line treatment of patients with metastatic colorectal cancer: Updated overall survival and molecular subgroup analyses of the open-label, phase 3 TRIBE study. Lancet Oncol 2015; 16: 1306-1315
• 16 Eisele RM, J. Z, Chopra S. et al. Results of liver resection in combination with radiofrequency ablation for hepatic malignancies. Eur J Surg Oncol 2010; 36: 269-274
• 17 Zimmermann M, Pedersoli F, Schulze-Hagen M. et al. Salvage RFA in patients with intrahepatic recurrence after major hepatic surgery for colorectal cancer liver metastases: Mid-term outcome. Eur Radiol 2020; 30: 1221-1227
• 18 Livraghi T, Solbiati L, Meloni F. et al. Percutaneous radiofrequency ablation of liver metastases in potential candidates for resection. Cancer 2003; 97: 3027-3035
• 19 Auguste P, Fallavollita L, Wang N. et al. The host inflammatory response promotes liver metastasis by increasing tumor cell arrest and extravasation. Am J Pathol 2007; 170: 1781-1792
• 20 Jansen MC, van Wanrooy S, van Hillegersberg R. et al. Assessment of systemic inflammatory response (SIR) in patients undergoing radiofrequency ablation or partial liver resection for liver tumors. Eur J Surg Oncol 2008; 34: 662-667
• 21 Zhao J, Li Q, Muktiali M. et al. Effect of microwave ablation treatment of hepatic malignancies on serum cytokine levels. BMC Cancer 2020; 20: 812
• 22 Okuno M, Kawaguchi Y, De Bellis M. et al. A new sequential treatment strategy for multiple colorectal liver metastases: Planned incomplete resection and postoperative completion ablation for intentionally-untreated tumors under guidance of cross-sectional imaging. Eur J Surg Oncol 2021; 47: 311-316
• 23 van der Bij GJ, Oosterling SJ, Beelen RH. et al. The perioperative period is an underutilized window of therapeutic opportunity in patients with colorectal cancer. Ann Surg 2009; 249: 727-734
• 24 Palma DA, Olson R, Harrow S. et al. Stereotactic Ablative Radiotherapy for the Comprehensive Treatment of Oligometastatic Cancers: Long-Term Results of the SABR-COMET Phase II Randomized Trial. J Clin Oncol 2020; 38: 2830-2838
• 25 Bale R, Widmann G, Schullian P. et al. Stereotaktische Radiofrequenzablation von kolorektalen Lebermetastasen – Langzeitüberleben. Rofo 2011; 183: VO207_203
• 26 Fong Z, Palazzo F, Needleman L. et al. Combined hepatic arterial embolization and hepatic ablation for unresectable colorectal metastases to the liver. Am Surg 2012; 78: 1243-1248
• 27 Matsuoka H, Morise Z, Tanaka C. et al. Repeat hepatectomy with systemic chemotherapy might improve survival of recurrent liver metastasis from colorectal cancer-a retrospective observational study. World J Surg Oncol 2019; 17: 33
• 28 Kanas GP, Taylor A, Primrose JN. et al. Survival after liver resection in metastatic colorectal cancer: Review and meta-analysis of prognostic factors. Clin Epidemiol 2012; 4: 283-301
• 29 van der Lei S, Puijk RS, Dijkstra M. et al. Thermal ablation versus surgical resection of small-size colorectal liver metastases (COLLISION): An international, randomised, controlled, phase 3 non-inferiority trial. Lancet Oncol 2025; 26: 187-199
• 30 Vera R, González-Flores E, Rubio C. et al. Multidisciplinary management of liver metastases in patients with colorectal cancer: A consensus of SEOM, AEC, SEOR, SERVEI, and SEMNIM. Clin Transl Oncol 2020; 22: 647-662
• 31 Amygdalos I, Hitpass L, Schmidt F. et al. Survival after combined resection and ablation is not inferior to that after resection alone, in patients with four or more colorectal liver metastases. Langenbecks Arch Surg 2023; 408: 343

Publication History

Received: 11 September 2025

Accepted after revision: 02 January 2026

Article published online:
06 February 2026