Selective Internal Radiation Therapy (SIRT) with yttrium-90 resin microspheres plus standard systemic chemotherapy regimen of FOLFOX versus FOLFOX alone as first-line treatment of non-resectable liver metastases from colorectal cancer: the SIRFLOX study

The Future of Interventions for Stage IV Colorectal Cancers

Future options for the management of stage IV colorectal cancer are primarily focused on personalized and directed therapies. Interventions include precision cancer medicine, utilizing nanocarrier platforms for directed chemotherapy, palliative pressurized intraperitoneal aerosol chemotherapy (PIPAC), adjunctive oncolytic virotherapy, and radioembolization techniques. Comprehensive genetic profiling provides specific tumor-directed therapy based on individual genetics. Biomimetic magnetic nanoparticles as chemotherapy delivery systems may reduce systemic side effects of traditional chemotherapy by targeting tumor cells and sparing healthy cells. PIPAC is a newly emerging option for patients with peritoneal metastasis from colorectal cancer and is now being used internationally, showing promising results as a palliative therapy for colorectal cancer. Oncolytic virotherapy is another emerging potential treatment option, especially when combined with standard chemotherapy and/or radiation, as well as immunotherapy. And finally, radioembolization with yttrium-90 ( 90 Y) microspheres has shown some success in treating patients with unresectable liver metastasis from colorectal cancer via selective arterial injection.

Prophylactic Medication during Radioembolization in Metastatic Liver Disease: Is It Really Necessary? A Retrospective Cohort Study and Systematic Review of the Literature

PURPOSE

Trans-arterial radioembolization is a well-studied tumoricidal treatment for liver malignancies; however, consensus and evidence regarding periprocedural prophylactic medication (PPM) are lacking.

METHODS

A single-center retrospective analysis from 2014 to 2020 was performed in patients treated with 90Y-glass microspheres for neuroendocrine or colorectal liver metastases. Inclusion criteria were the availability of at least 3 months of clinical, biochemical, and imaging follow-up and post-treatment 90Y-PET/CT imaging for the determination of the whole non-tumorous liver absorbed dose (Dh). Logistic regression models were used to investigate if variables (among which are P/UDCA and Dh) were associated with either clinical toxicity, biochemical toxicity, or hepatotoxicity. Additionally, a structured literature search was performed in November 2022 to identify all publications related to PPM use in radioembolization treatments.

RESULTS

Fifty-one patients received P/UDCA as post-treatment medication, while 19 did not. No correlation was found between toxicity and P/UDCA use. Dh was associated with biochemical toxicity (p = 0.05). A literature review resulted in eight relevant articles, including a total of 534 patients, in which no consistent advice regarding PPM was provided.

CONCLUSION

In this single-center, retrospective review, P/UDCA use did not reduce liver toxicity in patients with metastatic liver disease. The whole non-tumorous liver-absorbed dose was the only significant factor for hepatotoxicity. No standardized international guidelines or supporting evidence exist for PPM in radioembolization.

Interventional radiological therapies in colorectal hepatic metastases

Colorectal malignancy is the third most common cancer and one of the prevalent causes of death globally. Around 20-25% of patients present with metastases at the time of diagnosis, and 50-60% of patients develop metastases in due course of the disease. Liver, followed by lung and lymph nodes, are the most common sites of colorectal cancer metastases. In such patients, the 5-year survival rate is approximately 19.2%. Although surgical resection is the primary mode of managing colorectal cancer metastases, only 10-25% of patients are competent for curative therapy. Hepatic insufficiency may be the aftermath of extensive surgical hepatectomy. Hence formal assessment of future liver remnant volume (FLR) is imperative prior to surgery to prevent hepatic failure. The evolution of minimally invasive interventional radiological techniques has enhanced the treatment algorithm of patients with colorectal cancer metastases. Studies have demonstrated that these techniques may address the limitations of curative resection, such as insufficient FLR, bi-lobar disease, and patients at higher risk for surgery. This review focuses on curative and palliative role through procedures including portal vein embolization, radioembolization, and ablation. Alongside, we deliberate various studies on conventional chemoembolization and chemoembolization with irinotecan-loaded drug-eluting beads. The radioembolization with Yttrium-90 microspheres has evolved as salvage therapy in surgically unresectable and chemo-resistant metastases.

Transarterial Yttrium-90 Radioembolization in Intrahepatic Cholangiocarcinoma Patients: Outcome Assessment Applying a Prognostic Score

Radioembolization (RE) is a viable therapy option in patients with intrahepatic cholangiocarcinoma (ICC). This study delineates a prognostic score regarding overall survival (OS) after RE using routine pre-therapeutic parameters. A retrospective analysis of 39 patients (median age, 61 [range, 32−82] years; 26 females, 13 males) with ICC and 42 RE procedures was conducted. Cox regression for OS included age, ECOG, hepatic and extrahepatic tumor burden, thrombosis of the portal vein, ascites, laboratory parameters and dose reduction due to hepatopulmonary shunt. Median OS after RE was 8.0 months. Using univariable Cox, ECOG ≥ 1 (hazard ratio [HR], 3.8), AST/ALT quotient (HR, 1.86), high GGT (HR, 1.002), high CA19-9 (HR, 1.00) and dose reduction of 40% (HR, 3.8) predicted shorter OS (each p < 0.05). High albumin predicted longer OS (HR, 0.927; p = 0.045). Multivariable Cox confirmed GGT ≥ 750 [U/L] (HR, 7.84; p < 0.001), ECOG > 1 (HR, 3.76; p = 0.021), albumin ≤ 41.1 [g/L] (HR, 3.02; p = 0.006) as a three-point pre-therapeutic prognostic score. More specifically, median OS decreased from 15.3 months (0 risk factors) to 7.6 months (1 factor) or 1.8 months (≥2 factors; p < 0.001). The proposed score may aid in improved pre-therapeutic patient identification with (un-)favorable OS after RE and facilitate the balance between potential life prolongation and overaggressive patient selection.

The Role of Conventional TACE (cTACE) and DEBIRI-TACE in Colorectal Cancer Liver Metastases

Colorectal cancer (CRC) is one of the most common tumor entities worldwide and a common cause of cancer-associated death. Colorectal cancer liver metastases (CRLM) thereby constitute a severe life-limiting factor. The therapy of CRLM presents a major challenge and surgical resection as well as systemic chemotherapy remain the first-line treatment options. Over the years several locoregional, vascular- and image-based treatments offered by interventional radiologists have emerged when conventional therapies fail, or metastases recurrence occurs. Among such options is the conventional/traditional transarterial chemoembolization (cTACE) by local injection of a combination of chemotherapeutic- and embolic-agents. A similar treatment is the more recent irinotecan-loaded drug-eluting beads TACE (DEBIRI-TACE), which are administered using the same approach. Numerous studies have shown that these different types of chemoembolization can be applied in different clinical settings safely. Furthermore, such treatments can also be combined with other local or systemic therapies. Unfortunately, due to the incoherent patient populations of studies investigating TACE in CRLM, critics state that the definite evidence supporting positive patient outcomes is still lacking. In the following article we review studies on conventional and DEBIRI-TACE. Although highly dependent on the clinical setting, prior therapies and generally the study population, cTACE and DEBIRI-TACE show comparable results. We present the most representative studies on the different chemoembolization procedures and compare the results. Although there is compelling evidence for both approaches, further studies are necessary to determine which patients profit most from these therapies. In conclusion, we determine TACE to be a viable option in CRLM in different clinical settings. Nevertheless, a multidisciplinary approach is desired to offer patients the best possible care.

Local Treatments in the Unresectable Patient with Colorectal Cancer Metastasis: A Review from the Point of View of the Medical Oncologist

For patients with isolated liver metastases from colorectal cancer who are not candidates for potentially curative resections, non-surgical local treatments may be useful. Non-surgical local treatments are classified according to how the treatment is administered. Local treatments are applied directly on hepatic parenchyma, such as radiofrequency, microwave hyperthermia and cryotherapy. Locoregional therapies are delivered through the hepatic artery, such as chemoinfusion, chemoembolization or selective internal radiation with Yttrium 90 radioembolization. The purpose of this review is to describe the different interventional therapies that are available for these patients in routine clinical practice, the most important clinical trials that have tried to demonstrate the effectiveness of each therapy and recommendations from principal medical oncologic societies.

Biomarkers associated with survival and favourable outcome of radioembolization with yttrium-90 glass microspheres for colon cancer liver metastases: Single centre experience

OBJECTIVE

To determine the therapeutic effectiveness and safety of transarterial radioembolization (TARE) with Yttrium-90 in patients with colorectal cancer (CRC) liver metastases and to evaluate the prognostic value of different biomarkers.

MATERIAL AND METHODS

This prospective longitudinal study enrolled consecutive patients with CRC liver metastases treated with TARE between November 2015 and june 2020. The therapeutic response at three and six months (RECIST1.1 criteria) and the relationship of biomarkers with therapeutic response, by calculating objective tumor response rates (ORR) and disease control (DCR), and overall survival (OS) and progression-free (PFS).

RESULTS

Thirty TAREs were performed in 23 patients (mean age, 61.61 ± 9.13 years; 56.5% male). At three months, the objective response rate (ORR) was 16.7% and the disease control rate (DCR) 53.3%. At six months, the disease progressed in 80%. The ORR and DCR were significantly associated with age at diagnosis (P = 0.047), previous bevacizumab treatment (P = 0.008), pre-TARE haemoglobin (P = 0.008), NLR (P = 0.040), pre-TARE albumin (P = 0.012), pre-TARE ALT (P = 0.023) and tumour-absorbed dose > 115 Gy (P = 0.033). Median overall survival (OS) was 12 months (95% CI, 4.75-19.25 months) and median progression-free survival (PFS) 3 months (95% CI, 2.41-3.59). OS was significantly associated with primary tumour resection (P = 0.019), KRAS mutation (HR: 5.15; P = 0.024), pre-TARE haemoglobin (HR: 0.50; p = 0.009), pre-TARE NLR (HR: 1.65; P = 0.005) and PLR (HR: 1.01; P = 0.042).

CONCLUSION

TARE prognosis and therapeutic response were predicted by different biomarkers, ranging from biochemical parameters to tumour dosimetrics.

Selective Internal Radiation Therapy in Breast Cancer Liver Metastases: Outcome Assessment Applying a Prognostic Score

Selective internal radiation therapy (SIRT) is a therapy option in patients with breast cancer liver metastasis (BCLM). This analysis aimed at identifying a prognostic score regarding overall survival (OS) after SIRT using routine pretherapeutic parameters. Retrospective analysis of 38 patients (age, 59 (39-84) years) with BCLM and 42 SIRT procedures. Cox regression for OS included clinical factors (age, ECOG and prior treatments), laboratory parameters, hepatic tumor load and dose reduction due to hepatopulmonary shunt. Elevated baseline ALT and/or AST was present if CTCAE grade ≥ 2 was fulfilled (>3 times the upper limit of normal). Median OS after SIRT was 6.4 months. In univariable Cox, ECOG ≥ 1 (hazard ratio (HR), 3.8), presence of elevated baseline ALT/AST (HR, 3.8), prior liver surgery (HR, 10.2), and dose reduction of 40% (HR, 8.1) predicted shorter OS (each p < 0.05). Multivariable Cox confirmed ECOG ≥ 1 (HR, 2.34; p = 0.012) and elevated baseline ALT/AST (HR, 4.16; p < 0.001). Combining both factors, median OS decreased from 19.2 months (0 risk factors; n = 14 procedures) to 5.9 months (1 factor; n = 20) or 2.2 months (2 factors; n = 8; p < 0.001). The proposed score may facilitate pretherapeutic identification of patients with unfavorable OS after SIRT. This may help to balance potential life prolongation with the hazards of invasive treatment and hospitalization.

Biomarkers associated with survival and favourable outcome of radioembolization with yttrium-90 glass microspheres for colon cancer liver metastases: Single centre experience

OBJETIVE

To determine the therapeutic effectiveness and safety of transarterial radioembolization (TARE) with Yttrium-90 in patients with colorectal cancer (CRC) liver metastases and to evaluate the prognostic value of different biomarkers.

MATERIAL AND METHODS

This prospective longitudinal study enrolled consecutive patients with CRC liver metastases treated with TARE between November 2015 and june 2020. The therapeutic response at three and six months (RECIST1.1 criteria) and the relationship of biomarkers with therapeutic response, by calculating objective tumor response rates (ORR) and disease control (DCR), and overall survival (OS) and progression-free (PFS).

RESULTS

Thirty TAREs were performed in 23 patients (mean age, 61,61±9,13 years; 56,5% male). At three months, the objective response rate (ORR) was 16,7% and the disease control rate (DCR) 53,3%. At six months, the disease progressed in 80%. The ORR and DCR were significantly associated with age at diagnosis (P=.047), previous bevacizumab treatment (P=.008), pre-TARE haemoglobin (P=.008), NLR (P=.040), pre-TARE albumin (P=.012), pre-TARE ALT (P=.023) and tumour-absorbed dose>115Gy (P=.033). Median overall survival (OS) was 12 months (95% CI, 4.75-19.25 months) and median progression-free survival (PFS) 3 months (95% CI, 2.41-3.59). OS was significantly associated with primary tumour resection (P=.019), KRAS mutation (HR: 5.15; P=.024), pre-TARE haemoglobin (HR: .50; p=.009), pre-TARE NLR (HR: 1.65; P=.005) and PLR (HR: 1.01; P=.042).

CONCLUSION

TARE prognosis and therapeutic response were predicted by different biomarkers, ranging from biochemical parameters to tumour dosimetrics.

Combined quality and dose-volume histograms for assessing the predictive value of 99mTc-MAA SPECT/CT simulation for personalizing radioembolization treatment in liver metastatic colorectal cancer

Background

The relationship between the mean absorbed dose delivered to the tumour and the outcome in liver metastases from colorectal cancer patients treated with radioembolization has already been presented in several studies. The optimization of the personalized therapeutic activity to be administered is still an open challenge. In this context, how well the ^99mTc-MAA SPECT/CT predicts the absorbed dose delivered by radioembolization is essential. This work aimed to analyse the differences between predictive ^99mTc-MAA-SPECT/CT and post-treatment ⁹⁰Y-microsphere PET/CT dosimetry at different levels. Dose heterogeneity was compared voxel-to-voxel using the quality-volume histograms, subsequently used to demonstrate how it could be used to identify potential clinical parameters that are responsible for quantitative discrepancies between predictive and post-treatment dosimetry.

Results

We analysed 130 lesions delineated in twenty-six patients. Dose-volume histograms were computed from predictive and post-treatment dosimetry for all volumes: individual lesion, whole tumoural liver (TL) and non-tumoural liver (NTL). For all dose-volume histograms, the following indices were extracted: D₉₀, D₇₀, D₅₀, D_mean and D₂₀. The results showed mostly no statistical differences between predictive and post-treatment dosimetries across all volumes and for all indices. Notably, the analysis showed no difference in terms of D_mean, confirming the results from previous studies. Quality factors representing the spread of the quality-volume histogram (QVH) curve around 0 (ideal QF = 0) were determined for lesions, TL and NTL. QVHs were classified into good (QF < 0.18), acceptable (0.18 ≤ QF < 0.3) and poor (QF ≥ 0.3) correspondence. For lesions and TL, dose- and quality-volume histograms are mostly concordant: 69% of lesions had a QF within good/acceptable categories (40% good) and 65% of TL had a QF within good/acceptable categories (23% good). For NTL, the results showed mixed results with 48% QF within the poor concordance category. Finally, it was demonstrated how QVH analysis could be used to define the parameters that predict the significant differences between predictive and post-treatment dose distributions.

Conclusion

It was shown that the use of the QVH is feasible in assessing the predictive value of ^99mTc-MAA SPECT/CT dosimetry and in estimating the absorbed dose delivered to liver metastases from colorectal cancer via ⁹⁰Y-microspheres. QVH analyses could be used in combination with DVH to enhance the predictive value of ^99mTc-MAA SPECT/CT dosimetry and to assist personalized activity prescription.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40658-020-00345-4.

Liver Resection After Selective Internal Radiation Therapy with Yttrium-90: Safety and Outcomes

Introduction

Selective internal radiotherapy (SIRT) with yttrium-90 (Y-90) is an intra-arterial therapy for hepatic malignancy in patients who are unsuitable for surgical resection. This treatment is considered palliative, although some patients can demonstrate a response that is adequate to facilitate surgical resection with curative intent.

Methods

All patients who underwent liver resection post SIRT were reviewed. Data gathered included patient demographics, tumor type, surgical details, and post-operative outcomes.

Results

Twelve patients underwent SIRT followed by liver resection (7 males and 5 females). Pathologies were hepatocellular carcinoma (n = 5), metastatic colorectal cancer (n = 5), and neuroendocrine tumor (n = 2). Lesional response (size, volume, and RECIST (response evaluation criteria in solid tumors)) was calculated and where appropriate functional liver remnant (FLR) is presented. Mean FLR increase was 264cm³ (range − 123 to 909), and all cases demonstrated a partial response according to RECIST with a mean largest lesion volume reduction of 475cm³ (range 14–1632). No post-SIRT complications were noted. Hepatectomy occurred at a mean of 322 days from SIRT treatment. Ninety-day morbidity was 67% (n = 6), complications post-surgery were analyzed according to the Clavien-Dindo classification scale; a total of 15 events occurred in 6 patients. Ninety-day mortality of 11% (n = 1).

Conclusion

In selected cases, liver resection is possible post SIRT. As this can represent a potentially curative option, it is important to reconsider resection in the follow-up of patients undergoing SIRT. Post-operative complications are noted following major and extended liver resection. Therefore, further studies are needed to improve patient selection.

Radioembolization for neuroendocrine liver metastases is safe and effective prior to major hepatic resection

Background

Radioembolization (RE) is well established in the treatment of neuroendocrine liver metastases. However surgery is rarely performed after RE, although liver resection is the gold standard in the treatment of localized neuroendocrine liver metastases. Therefore, aim of the present study was to evaluate the safety and feasibility of liver resection after RE in a homogenous cohort.

Methods

From a prospective surgical (n=494) and nuclear medical (n=138) database patients with NELM who underwent liver resection and/or RE were evaluated. Between September 2011 and December 2017 eight patients could be identified who underwent liver resection after RE (mean therapeutic activity of 1,746 Mbq). Overall and progression free survival were evaluated as well as epidemiological and perioperative factors. The surgical specimens were analyzed for necrosis, fibrosis, inflammation, and steatosis.

Results

The mean hepatic tumor load of patients, who had liver surgery after RE, was 31.4% with a mean Ki-67 proliferation index of 5.9%. The majority of these patients (7/8) received whole liver RE prior to liver resection, which did not increase morbidity and mortality compared to a surgical collective. Indications for RE were oncological (6/8) or carcinoid syndrome associated reasons (2/8). Mean overall survival was 25.1 months after RE and subsequent surgery. Tumor necrosis in radioembolized lesions was 29.4% without evidence of fibrosis and inflammation in hepatic tissue.

Conclusions

This is the first study analyzing the multimodal therapeutic approach of liver resection following whole liver RE. This treatment algorithm is safe, does not lead to an increased morbidity and is associated with a favorable oncological outcome. Nonetheless, patient selection remains a key issue.

Quality of life in the FOXFIRE, SIRFLOX and FOXFIRE-global randomised trials of selective internal radiotherapy for metastatic colorectal cancer

Selective internal radiotherapy (SIRT) is a liver-directed treatment involving the injection of yttrium-90 microspheres into the blood supply of liver tumours. There are very few studies assessing health-related quality of life (HRQOL) in patients treated with SIRT. Patients with liver metastases from colorectal cancer (CRC) were randomised in the FOXFIRE (FFr; ISRCTN83867919), SIRFLOX (SF; NCT00724503) and FOXFIRE-Global (FFrG; NCT01721954) trials of first-line oxaliplatin-fluorouracil (FOLFOX) chemotherapy combined with SIRT versus FOLFOX alone. HRQOL was assessed using the three-level EQ-5D, European Organisation for Research and Treatment of Cancer Quality of Life (EORTC QLQ-C30) and EORTC Colorectal Liver Metastases cancer module (EORTC QLQ-LMC21) at baseline, ≤3 months, 6 months, 12 months and annually thereafter from randomisation, and at disease progression. Analyses were conducted on an intention-to-treat basis. In total, 554 patients were randomised to SIRT + FOLFOX and 549 patients to FOLFOX alone. HRQOL was statistically significant lower in SIRT + FOLFOX patients ≤3 months after SIRT administration in all three instruments, particularly global health, physical and role functioning and symptoms of fatigue, nausea/vomiting and appetite loss. By accepted thresholds, these differences were deemed not clinically important. Differences between SIRT + FOLFOX and FOLFOX alone over the 2-year follow up and at disease progression were also not clinically important. Although there is some decrease in HRQOL for up to 3 months following SIRT, the addition of SIRT to FOLFOX chemotherapy does not change HRQOL to a clinically important degree in metastatic CRC patients.

Critical review of multidisciplinary non-surgical local interventional ablation techniques in primary or secondary liver malignancies

Local non-surgical interventional percutaneous ablation represents nowadays an important part of the potential treatment strategies. Although surgical ablation represents the gold standard, in the past decade there was an expansion in the use of non-surgical ablative techniques: radiofrequency, microwave, laser, cryoablation, irreversible electroporation, and interventional radiotherapy (brachytherapy) in primary as well as secondary liver cancers. With the growing experience in the field, there was implemented a new pillar for cancer treatment, together with surgery, chemotherapy as well as radiotherapy, so-called interventional oncology (IO). To date, there are no published papers regarding a comparative interdisciplinary evaluation of all these non-surgical interventional local ablation therapies. Our paper offers a critical interdisciplinary overview of the treatments in both primary and secondary liver tumors, including from a cost-effective point of view. Furthermore, the present status of education in IO and a comparison of actual economic aspects of the treatments are also provided.

Radioembolization for the Treatment of Primary and Metastatic Liver Cancers

Radioembolization using ⁹⁰Y microspheres (glass or resin) has been introduced as an effective intraarterial therapy for unresectable primary and metastatic liver cancers. Although the basic therapeutic effect of chemoembolization results from ischemia, the therapeutic efficacy of radioembolization comes from radiation. Furthermore, compared with surgical resection and local ablation therapy, radioembolization is available with less limitation on the sites or number of liver cancers. The radioisotope ⁹⁰Y is a β-radiation emitter without γ-radiation, with the emission of secondary bremsstrahlung photons and small numbers of positrons. Administration of ⁹⁰Y microspheres into the hepatic artery can deliver a high dose of radiation selectively to the target tumor with limited radiation exposure to the surrounding normal parenchyma, and has low systemic toxicity. In general, radioembolization has been considered for patients with unresectable primary or metastatic liver-only or liver-dominant cancers with no ascites or other clinical signs of liver failure, life expectancy of > 12 weeks, and good performance status. Here, we review the current radioactive compounds, pretreatment assessment, and indications for radioembolization in patients with hepatocellular carcinoma, intrahepatic cholangiocarcinoma, and liver metastases from colorectal cancer.

Secondary technical resectability of colorectal cancer liver metastases after chemotherapy with or without selective internal radiotherapy in the randomized SIRFLOX trial

Background

Secondary resection of initially unresectable colorectal cancer liver metastases (CRLM) can prolong survival. The added value of selective internal radiotherapy (SIRT) to downsize lesions for resection is not known. This study evaluated the change in technical resectability of CRLM with the addition of SIRT to FOLFOX‐based chemotherapy.

Methods

Baseline and follow‐up hepatic imaging of patients who received modified FOLFOX (mFOLFOX6: fluorouracil, leucovorin, oxaliplatin) chemotherapy with or without bevacizumab (control arm) versus mFOLFOX6 (with or without bevacizumab) plus SIRT using yttrium‐90 resin microspheres (SIRT arm) in the phase III SIRFLOX trial were reviewed by three or five (of 14) expert hepatopancreatobiliary surgeons for resectability. Reviewers were blinded to one another, treatment assignment, extrahepatic disease status, and information on clinical and scanning time points. Technical resectability was defined as at least 60 per cent of reviewers (3 of 5, or 2 of 3) assessing a patient's liver metastases as surgically removable.

Results

Some 472 patients were evaluable (SIRT, 244; control, 228). There was no significant baseline difference in the proportion of technically resectable liver metastases between SIRT (29, 11·9 per cent) and control (25, 11·0 per cent) arms (P = 0·775). At follow‐up, significantly more patients in both arms were deemed technically resectable compared with baseline: 159 of 472 (33·7 per cent) versus 54 of 472 (11·4 per cent) respectively (P = 0·001). More patients were resectable in the SIRT than in the control arm: 93 of 244 (38·1 per cent) versus 66 of 228 (28·9 per cent) respectively (P < 0·001).

Conclusion

Adding SIRT to chemotherapy may improve the resectability of unresectable CRLM.

Personalised radioembolization improves outcomes in refractory intra-hepatic cholangiocarcinoma: a multicenter study

PURPOSE

Reported outcomes of patients with intra-hepatic cholangiocarcinoma (IH-CCA) treated with radioembolization are highly variable, which indicates differences in included patients' characteristics and/or procedure-related variables. This study aimed to identify patient- and treatment-related variables predictive for radioembolization outcome.

METHODS

This retrospective multicenter study enrolled 58 patients with unresectable and chemorefractory IH-CCA treated with resin ⁹⁰Y-microspheres. Clinicopathologic data were collected from patient records. Metabolic parameters of liver tumor(s) and presence of lymph node metastasis were measured on baseline ¹⁸F-FDG-PET/CT. ^99mTc-MAA tumor to liver uptake ratio (TLR_MAA) was computed for each lesion on the SPECT-CT. Activity prescription using body-surface-area (BSA) or more personalized partition-model was recorded. The study endpoint was overall survival (OS) starting from date of radioembolization. Statistical analysis was performed by the log-rank test and multivariate Cox's proportional hazards model.

RESULTS

Median OS (mOS) post-radioembolization of the entire cohort was 10.3 months. Variables associated with significant differences in terms of OS were serum albumin (hazard ratio (HR) = 2.78, 95%CI:1.29-5.98, p = 0.002), total bilirubin (HR = 2.17, 95%CI:1.14-4.12, p = 0.009), aspartate aminotransferase (HR = 2.96, 95%CI:1.50-5.84, p < 0.001), alanine aminotransferase (HR = 2.02, 95%CI:1.05-3.90, p = 0.01) and γ-GT (HR = 2.61, 95%CI:1.31-5.22, p < 0.001). The presence of lymph node metastasis as well as a TLR_MAA < 1.9 were associated with shorter mOS: HR = 2.35, 95%CI:1.08-5.11, p = 0.008 and HR = 2.92, 95%CI:1.01-8.44, p = 0.009, respectively. Finally, mOS was significantly shorter in patients treated according to the BSA method compared to the partition-model: mOS of 5.5 vs 14.9 months (HR = 2.52, 95%CI:1.23-5.16, p < 0.001). Multivariate analysis indicated that the only variable that increased outcome prediction above the clinical variables was the activity prescription method with HR of 2.26 (95%CI:1.09-4.70, p = 0.03). The average mean radiation dose to tumors was significantly higher with the partition-model (86Gy) versus BSA (38Gy).

CONCLUSION

Radioembolization efficacy in patients with unresectable recurrent and/or chemorefractory IH-CCA strongly depends on the tumor radiation dose. Personalized activity prescription should be performed.

Multi-modal image analysis for semi-automatic segmentation of the total liver and liver arterial perfusion territories for radioembolization

Purpose

We have developed a multi-modal imaging approach for SIRT, combining ^99mTc-MAA SPECT/CT and/or ⁹⁰Y PET, ¹⁸F-FDG PET/CT, and contrast-enhanced CBCT for voxel-based dosimetry, as a tool for treatment planning and verification. For radiation dose prediction calculations, a segmentation of the total liver volume and of the liver perfusion territories is required.

Method

In this paper, we proposed a procedure for multi-modal image analysis to assist SIRT treatment planning. The pre-treatment ¹⁸F-FDG PET/CT, ^99mTc-MAA SPECT/CT, and contrast-enhanced CBCT images were registered to a common space using an initial rigid, followed by a deformable registration. The registration was scored by an expert using Likert scores. The total liver was segmented semi-automatically based on the PET/CT and SPECT/CT images, and the liver perfusion territories were determined based on the CBCT images. The segmentations of the liver and liver lobes were compared to the manual segmentations by an expert on a CT image.

Result

Our methodology showed that multi-modal image analysis can be used for determination of the liver and perfusion territories using CBCT in SIRT using all pre-treatment studies. The results for image registration showed acceptable alignment with limited impact on dosimetry.

The image registration performs well according to the expert reviewer (scored as perfect or with little misalignment in 94% of the cases). The semi-automatic liver segmentation agreed well with manual liver segmentation (dice coefficient of 0.92 and an average Hausdorff distance of 3.04 mm). The results showed disagreement between lobe segmentation using CBCT images compared to lobe segmentation based on CT images (average Hausdorff distance of 14.18 mm), with a high impact on the dosimetry (differences up to 9 Gy for right and 21 Gy for the left liver lobe).

Conclusion

This methodology can be used for pre-treatment dosimetry and for SIRT planning including the determination of the activity that should be administered to achieve the therapeutical goal. The inclusion of perfusion CBCT enables perfusion-based definition of the liver lobes, which was shown to be markedly different from the anatomical definition in some of the patients.

The physics of radioembolization

Radioembolization is an established treatment for chemoresistant and unresectable liver cancers. Currently, treatment planning is often based on semi-empirical methods, which yield acceptable toxicity profiles and have enabled the large-scale application in a palliative setting. However, recently, five large randomized controlled trials using resin microspheres failed to demonstrate a significant improvement in either progression-free survival or overall survival in both hepatocellular carcinoma and metastatic colorectal cancer. One reason for this might be that the activity prescription methods used in these studies are suboptimal for many patients.In this review, the current dosimetric methods and their caveats are evaluated. Furthermore, the current state-of-the-art of image-guided dosimetry and advanced radiobiological modeling is reviewed from a physics' perspective. The current literature is explored for the observation of robust dose-response relationships followed by an overview of recent advancements in quantitative image reconstruction in relation to image-guided dosimetry.This review is concluded with a discussion on areas where further research is necessary in order to arrive at a personalized treatment method that provides optimal tumor control and is clinically feasible.

SIRT1-ZEB1-positive feedback promotes epithelial-mesenchymal transition process and metastasis of osteosarcoma

Osteosarcoma is the most common malignant bone cancer that mainly affects children and young adults. Recently, the NAD⁺ -dependent deacetylase, sirtuin 1 (SIRT1), has been reported to play a key role in the development of malignant tumors. The study aimed to investigate the role of SIRT1 in osteosarcoma and explore its underlying oncogenic mechanisms. The prognostic value of SIRT1 in osteosarcoma was assessed through detection of SIRT1 expression based on osteosarcoma biopsy tissue. Then, to further investigate the effect of SIRT1 in osteosarcoma, osteosarcoma cells were treated with small interfering RNA SIRT1 and overexpressed SIRT1 to detect the cell migration, invasion, and epithelial-mesenchymal transition (EMT). The levels of SIRT1 expression were significantly higher in osteosarcoma tissues than those in adjacent normal tissues, and the SIRT1 protein level may be coupled with metastatic and poor prognosis risk in patients with osteosarcoma. Moreover, SIRT1 silencing inhibited the migration as well as invasion ability of osteosarcoma cells in vitro, and SIRT1 upregulation reversed those effects. Finally, we found that SIRT1-ZEB1-positive feedback enhanced the EMT process and metastasis of osteosarcoma. Altogether, the results of the current study revealed that high levels of SIRT1 might be a biomarker for a high metastatic rate in patients with osteosarcoma, which suggested that inhibition of SIRT1 might be promising for the therapeutics of osteosarcoma.

Treatment of Primary Liver Tumors and Liver Metastases, Part 1: Nuclear Medicine Techniques

⁹⁰Y radioembolization is an increasingly used treatment for both primary and metastatic malignancy in the liver. Understanding the biophysical properties, dosing concerns, and imaging appearance of this treatment is important for interventional radiologists and nuclear medicine physicians to provide important therapy. ⁹⁰Y radioembolization is efficacious and safe, although the possibility of complications does exist. This article provides a comprehensive in-depth discussion about the indications for ⁹⁰Y radioembolization, reviews the role of preprocedural angiography and ^99mTc-macroaggregated albumin scans, illustrates different dosing techniques, compares and contrasts resin and glass microspheres, and describes potential complications.

Effect of Primary Tumor Side on Survival Outcomes in Untreated Patients With Metastatic Colorectal Cancer When Selective Internal Radiation Therapy Is Added to Chemotherapy: Combined Analysis of Two Randomized Controlled Studies

BACKGROUND

The primary tumor side is emerging as a major prognostic factor for patients with metastatic colorectal cancer (mCRC). We examined the survival data from 2 randomized studies to determine whether the outcomes differ between patients with mCRC with right-sided primary (RSP) tumors and those with left-sided primary (LSP) tumors after selective internal radiation therapy (SIRT) plus mFOLFOX6 (folinic acid [leucovorin], 5-fluorouracil, oxaliplatin) chemotherapy, versus chemotherapy alone.

PATIENTS AND METHODS

Separate and combined analyses were performed on the data from the SIRFLOX and FOXFIRE global trials, which compared chemotherapy plus SIRT with chemotherapy alone for patients with mCRC liver metastases. The primary tumor side data were prospectively collected. The principal outcome measure was overall survival (OS) stratified by treatment and primary tumor side.

RESULTS

In the combined analysis of all 739 patients enrolled, SIRT had no effect on OS (median OS, 24.3 vs. 24.6 months; hazard ratio [HR], 1.021; P = .810). For the 179 patients (24.2%) with a RSP tumor, OS was improved with the addition of SIRT (median, 22.0 vs. 17.1 months HR, 0.641; P = .008). The addition of SIRT was not associated with a significant difference in OS among the 540 patients with a LSP tumor (median, 24.6 vs. 26.6 months; HR, 1.120; P = .264). A test of treatment interaction by primary tumor side was statistically significant for RSP and SIRT (P = .002).

CONCLUSION

The addition of SIRT for patients with RSP tumors, but not for those with LSP tumors, was associated with a statistically and clinically significant OS gain.

First-line selective internal radiotherapy plus chemotherapy versus chemotherapy alone in patients with liver metastases from colorectal cancer (FOXFIRE, SIRFLOX, and FOXFIRE-Global): a combined analysis of three multicentre, randomised, phase 3 trials

BACKGROUND

Data suggest selective internal radiotherapy (SIRT) in third-line or subsequent therapy for metastatic colorectal cancer has clinical benefit in patients with colorectal liver metastases with liver-dominant disease after chemotherapy. The FOXFIRE, SIRFLOX, and FOXFIRE-Global randomised studies evaluated the efficacy of combining first-line chemotherapy with SIRT using yttrium-90 resin microspheres in patients with metastatic colorectal cancer with liver metastases. The studies were designed for combined analysis of overall survival.

METHODS

FOXFIRE, SIRFLOX, and FOXFIRE-Global were randomised, phase 3 trials done in hospitals and specialist liver centres in 14 countries worldwide (Australia, Belgium, France, Germany, Israel, Italy, New Zealand, Portugal, South Korea, Singapore, Spain, Taiwan, the UK, and the USA). Chemotherapy-naive patients with metastatic colorectal cancer (WHO performance status 0 or 1) with liver metastases not suitable for curative resection or ablation were randomly assigned (1:1) to either oxaliplatin-based chemotherapy (FOLFOX: leucovorin, fluorouracil, and oxaliplatin) or FOLFOX plus single treatment SIRT concurrent with cycle 1 or 2 of chemotherapy. In FOXFIRE, FOLFOX chemotherapy was OxMdG (oxaliplatin modified de Gramont chemotherapy; 85 mg/m2 oxaliplatin infusion over 2 h, L-leucovorin 175 mg or D,L-leucovorin 350 mg infusion over 2 h, and 400 mg/m2 bolus fluorouracil followed by a 2400 mg/m2 continuous fluorouracil infusion over 46 h). In SIRFLOX and FOXFIRE-Global, FOLFOX chemotherapy was modified FOLFOX6 (85 mg/m2 oxaliplatin infusion over 2 h, 200 mg leucovorin, and 400 mg/m2 bolus fluorouracil followed by a 2400 mg/m2 continuous fluorouracil infusion over 46 h). Randomisation was done by central minimisation with four factors: presence of extrahepatic metastases, tumour involvement of the liver, planned use of a biological agent, and investigational centre. Participants and investigators were not masked to treatment. The primary endpoint was overall survival, analysed in the intention-to-treat population, using a two-stage meta-analysis of pooled individual patient data. All three trials have completed 2 years of follow-up. FOXFIRE is registered with the ISRCTN registry, number ISRCTN83867919. SIRFLOX and FOXFIRE-Global are registered with ClinicalTrials.gov, numbers NCT00724503 (SIRFLOX) and NCT01721954 (FOXFIRE-Global).

FINDINGS

Between Oct 11, 2006, and Dec 23, 2014, 549 patients were randomly assigned to FOLFOX alone and 554 patients were assigned FOLFOX plus SIRT. Median follow-up was 43·3 months (IQR 31·6-58·4). There were 411 (75%) deaths in 549 patients in the FOLFOX alone group and 433 (78%) deaths in 554 patients in the FOLFOX plus SIRT group. There was no difference in overall survival (hazard ratio [HR] 1·04, 95% CI 0·90-1·19; p=0·61). The median survival time in the FOLFOX plus SIRT group was 22·6 months (95% CI 21·0-24·5) compared with 23·3 months (21·8-24·7) in the FOLFOX alone group. In the safety population containing patients who received at least one dose of study treatment, as treated, the most common grade 3-4 adverse event was neutropenia (137 [24%] of 571 patients receiving FOLFOX alone vs 186 (37%) of 507 patients receiving FOLFOX plus SIRT). Serious adverse events of any grade occurred in 244 (43%) of 571 patients receiving FOLFOX alone and 274 (54%) of 507 patients receiving FOLFOX plus SIRT. 10 patients in the FOLFOX plus SIRT group and 11 patients in the FOLFOX alone group died due to an adverse event; eight treatment-related deaths occurred in the FOLFOX plus SIRT group and three treatment-related deaths occurred in the FOLFOX alone group.

INTERPRETATION

Addition of SIRT to first-line FOLFOX chemotherapy for patients with liver-only and liver-dominant metastatic colorectal cancer did not improve overall survival compared with that for FOLFOX alone. Therefore, early use of SIRT in combination with chemotherapy in unselected patients with metastatic colorectal cancer cannot be recommended. To further define the role of SIRT in metastatic colorectal cancer, careful patient selection and studies investigating the role of SIRT as consolidation therapy after chemotherapy are needed.

FUNDING

Bobby Moore Fund of Cancer Research UK, Sirtex Medical.

Metastatic Liver Disease: Indications for Locoregional Therapy and Supporting Data

Metastatic liver disease is a major cause of cancer-related morbidity and mortality. Surgical resection is considered the only curative treatment, yet only a minority is eligible. Patients who present with unresectable disease are treated with systemic agents and/or locoregional therapies. The latter include thermal ablation and catheter-based transarterial interventions. Thermal ablation is reserved for those with limited tumor burden. It is used to downstage the disease to enable curative surgical resection, as an adjunct to surgery, or in select patients it is potentially curative. Transarterial therapies are indicated in those with more diffuse disease. The goals of care are to palliate symptoms and prolong survival. The indications and supporting data for thermal ablation and transarterial interventions are reviewed, technical and tumor factors that need to be considered prior to intervention are outlined, and finally several cases are presented.

Protocol for Combined Analysis of FOXFIRE, SIRFLOX, and FOXFIRE-Global Randomized Phase III Trials of Chemotherapy +/- Selective Internal Radiation Therapy as First-Line Treatment for Patients With Metastatic Colorectal Cancer

BACKGROUND

In colorectal cancer (CRC), unresectable liver metastases are associated with a poor prognosis. The FOXFIRE (an open-label randomized phase III trial of 5-fluorouracil, oxaliplatin, and folinic acid +/- interventional radioembolization as first-line treatment for patients with unresectable liver-only or liver-predominant metastatic colorectal cancer), SIRFLOX (randomized comparative study of FOLFOX6m plus SIR-Spheres microspheres versus FOLFOX6m alone as first-line treatment in patients with nonresectable liver metastases from primary colorectal carcinoma), and FOXFIRE-Global (assessment of overall survival of FOLFOX6m plus SIR-Spheres microspheres versus FOLFOX6m alone as first-line treatment in patients with nonresectable liver metastases from primary colorectal carcinoma in a randomized clinical study) clinical trials were designed to evaluate the efficacy and safety of combining first-line chemotherapy with selective internal radiation therapy (SIRT) using yttrium-90 resin microspheres, also called transarterial radioembolization.

OBJECTIVE

The aim of this analysis is to prospectively combine clinical data from 3 trials to allow adequate power to evaluate the impact of chemotherapy with SIRT on overall survival.

METHODS

Eligible patients are adults with histologically confirmed CRC and unequivocal evidence of liver metastases which are not treatable by surgical resection or local ablation with curative intent at the time of study entry. Patients may also have limited extrahepatic metastases. Final analysis will take place when all participants have been followed up for a minimum of 2 years.

RESULTS

Efficacy and safety estimates derived using individual participant data (IPD) from SIRFLOX, FOXFIRE, and FOXFIRE-Global will be pooled using 2-stage prospective meta-analysis. Secondary outcome measures include progression-free survival (PFS), liver-specific PFS, health-related quality of life, response rate, resection rate, and adverse event profile. The large study population will facilitate comparisons of low frequency adverse events and allow for more robust safety analyses. The potential treatment benefit in those patients who present with disease confined to the liver will be investigated using 1-stage IPD meta-analysis. Efficacy will be analyzed on an intention-to-treat basis.

CONCLUSIONS

This analysis will assess the impact of SIRT combined with chemotherapy on overall survival in the first-line treatment of metastatic CRC. If positive, the results will change the standard of care for this disease.

TRIAL REGISTRATION

FOXFIRE ISRCTN Registry ISRCTN83867919; http://www.isrctn.com/ISRCTN83867919 (Archived by WebCite at http://www.webcitation.org/6oN7axrvA). SIRFLOX ClinicalTrials.gov NCT00724503; https://clinicaltrials.gov/ ct2/show/NCT00724503 (Archived by WebCite at http://www.webcitation.org/6oN7lEGbD). FOXFIRE-Global ClinicalTrials.gov NCT01721954; https://clinicaltrials.gov/ct2/show/NCT01721954 (Archived by WebCite at http://www.webcitation.org/ 6oN7vvQvG).

Transarterial Therapy for Colorectal Liver Metastases

Until recently, hepatic arterial therapies (HAT) had been used for colorectal liver metastases after failure of first-, second-, and third-line chemotherapies. HAT has gained greater acceptance in patients with liver-dominant colorectal metastases after failure of surgery or systemic chemotherapy. The current data demonstrate that HAT is a safe and effective option for preoperative downsizing, optimizing the time to surgery, limiting non-tumor-bearing liver toxicity, and improving overall survival after surgery in patients with colorectal liver-only metastases. The aim of this review is to present the current data for HAT in liver-only and liver-dominant colorectal liver metastases.

SIRFLOX: Randomized Phase III Trial Comparing First-Line mFOLFOX6 (Plus or Minus Bevacizumab) Versus mFOLFOX6 (Plus or Minus Bevacizumab) Plus Selective Internal Radiation Therapy in Patients With Metastatic Colorectal Cancer

Purpose

SIRFLOX was a randomized, multicenter trial designed to assess the efficacy and safety of adding selective internal radiation therapy (SIRT) using yttrium-90 resin microspheres to standard fluorouracil, leucovorin, and oxaliplatin (FOLFOX)–based chemotherapy in patients with previously untreated metastatic colorectal cancer.

Patients and Methods

Chemotherapy-naïve patients with liver metastases plus or minus limited extrahepatic metastases were randomly assigned to receive either modified FOLFOX (mFOLFOX6; control) or mFOLFOX6 plus SIRT (SIRT) plus or minus bevacizumab. The primary end point was progression-free survival (PFS) at any site as assessed by independent centralized radiology review blinded to study arm.

Results

Between October 2006 and April 2013, 530 patients were randomly assigned to treatment (control, 263; SIRT, 267). Median PFS at any site was 10.2 v 10.7 months in control versus SIRT (hazard ratio, 0.93; 95% CI, 0.77 to 1.12; P = .43). Median PFS in the liver by competing risk analysis was 12.6 v 20.5 months in control versus SIRT (hazard ratio, 0.69; 95% CI, 0.55 to 0.90; P = .002). Objective response rates (ORRs) at any site were similar (68.1% v 76.4% in control v SIRT; P = .113). ORR in the liver was improved with the addition of SIRT (68.8% v 78.7% in control v SIRT; P = .042). Grade ≥ 3 adverse events, including recognized SIRT-related effects, were reported in 73.4% and 85.4% of patients in control versus SIRT.

Conclusion

The addition of SIRT to FOLFOX-based first-line chemotherapy in patients with liver-dominant or liver-only metastatic colorectal cancer did not improve PFS at any site but significantly delayed disease progression in the liver. The safety profile was as expected and was consistent with previous studies.

Characterization of CC-531 as a Rat Model of Colorectal Liver Metastases

Purpose

Surgical resection of colorectal liver metastases is not achievable in more than 70% of the cases. Although the liver directed therapies have become a part of the stand of care, lack of a preclinical model impedes the assessment of toxicity and therapeutic benefits attributed several candidate drugs or treatment regimens that can be designed. In the present study we aim develop and characterize a rat colorectal liver metastasis model.

Materials and Methods

Growth characteristics of CC-531 cells were determined in vitro followed by subcapsular liver implantation in syngeneic WAG/Rij rats. Tumor growth progression was followed over 3 weeks by ultrasound (US) and magnetic resonance imaging (MRI). Growth characteristics were also assessed by histopathology and immunohistochemistry in harvested tumor tissues.

Results

The doubling time of CC-531 cells was found be under 24hrs and all the implanted rats grew tumors. US imaging showed hypoechoic masses and MRI showed contrast enhancement representing complex tumor microenvironments. Hematoxylin and Eosin staining confirmed tumor growth and uniform CD31 staining in tumor confirmed even vessel density.

Conclusion

CC-531 can be used as a metastatic rat tumor colorectal liver metastases model with well-defined characteristics that can be readily followed by imaging whilst having a therapeutic window for interventions.

Current and Future Theranostic Applications of the Lipid-Calcium-Phosphate Nanoparticle Platform

Over the last four years, the Lipid-Calcium-Phosphate (LCP) nanoparticle platform has shown success in a wide range of treatment strategies, recently including theranostics. The high specific drug loading of radiometals into LCP, coupled with its ability to efficiently encapsulate many types of cytotoxic agents, allows a broad range of theranostic applications, many of which are yet unexplored. In addition to providing an overview of current medical imaging modalities, this review highlights the current theranostic applications for LCP using SPECT and PET, and discusses potential future uses of the platform by comparing it with both systemically and locally delivered clinical radiotherapy options as well as introducing its applications as an MRI contrast agent. Strengths and weaknesses of LCP and of nanoparticles in general are discussed, as well as caveats regarding the use of fluorescence to determine the accumulation or biodistribution of a probe.

Yttrium-90 hepatic radioembolization: clinical review and current techniques in interventional radiology and personalized dosimetry

In recent years, yttrium-90 ((90)Y) microsphere radioembolization has been establishing itself as a safe and efficacious treatment for both primary and metastatic liver cancers. This extends to both first-line therapies as well as in the salvage setting. In addition, radioembolization appears efficacious for patients with portal vein thrombosis, which is currently a contraindication for surgery, transplantation and transarterial chemoembolization. This article reviews the efficacy and expanding use of (90)Y microsphere radioembolization with an added emphasis on recent advances in personalized dosimetry and interventional radiology techniques. Directions for future research into combination therapies with radioembolization and expansion into sites other than the liver are also explored.

Evidence-based medical oncology and interventional radiology paradigms for liver-dominant colorectal cancer metastases

Colorectal cancer metastasizes predictably, with liver predominance in most cases. Because liver involvement has been shown to be a major determinant of survival in this population, liver-directed therapies are increasingly considered even in cases where there is (limited) extrahepatic disease. Unfortunately, these patients carry a known risk of recurrence in the liver regardless of initial therapy choice. Therefore, there is a demand for minimally invasive, non-surgical, personalized cancer treatments to preserve quality of life in the induction, consolidation, and maintenance phases of cancer therapy. This report aims to review evidence-based conceptual, pharmacological, and technological paradigm shifts in parenteral and percutaneous treatment strategies as well as forthcoming evidence regarding next-generation systemic, locoregional, and local treatment approaches for this patient population.

Colorectal cancer: Metastases to a single organ

Colorectal cancer (CRC) is a common malignancy worldwide. In CRC patients, metastases are the main cause of cancer-related mortality. In a group of metastatic CRC patients, the metastases are limited to a single site (solitary organ); the liver and lungs are the most commonly involved sites. When metastatic disease is limited to the liver and/or lungs, the resectability of the metastatic lesions will dictate the management approach and the outcome. Less commonly, the site of solitary organ CRC metastasis is the peritoneum. In these patients, cytoreduction followed by hyperthermic intraperitoneal chemotherapy may improve the outcome. Rarely, CRC involves other organs, such as the brain, bone, adrenals and spleen, as the only site of metastatic disease. There are limited data to guide clinical practice in these cases. Here, we have reviewed the disease characteristics, management approaches and prognosis based on the metastatic disease site in patients with CRC with metastases to a single organ.