Evaluation of a strategy using pretherapeutic fiducial marker placement to avoid missing liver metastases

A Systematic Review of Disappearing Colorectal Liver Metastases: Resection or No Resection?

Background: Colorectal cancer is the second most common type of cancer and a leading cause of cancer-related deaths worldwide. Approximately 15% of the patients with colorectal cancer will already have liver metastases (CRLMs) at diagnosis. Luckily, the advances in chemotherapy regimens during the past few decades have led to increased rates of disease regression that could even render an originally unresectable disease resectable. In certain patients with CRLMs, the hepatic lesions are missing on preoperative imaging after neoadjuvant chemotherapy. These patients can undergo surgery with or without resection of the sites of the disappearing liver metastases (DLMs). In this systematic review, we assess the recurrence rate of the DLMs that were left unresected as well as the complete pathologic response of those resected. Methods: A literature search was conducted in PubMed for studies including patients with CRLMs who received neoadjuvant chemotherapy and had DLMs in preoperative imaging. Two independent reviewers completed the search according to the PRISMA checklist. Results: Three hundred and twenty-six patients with 1134 DLMs were included in our review. A total of 47 out of 480 DLMs (72.29%) that were removed had viable tumor cells in postoperative histology. One hundred and forty-five tumors could not be identified intraoperatively and were removed based on previous imaging, with thirty (20.69%) of them presenting viable cancer cells. Four hundred and sixty-five lesions could not be identified and were left in place. Of them, 152 (32.69%) developed local recurrence within 5 years. Of note, 34 DLMs could not be categorized as viable or non-viable tumors. Finally, DLMs that were identifiable intraoperatively had a higher possibility of viable tumors compared to non-identifiable ones (72.29% vs. 20.69%, respectively). Conclusions: Disappearing liver metastases that are left unresected have an increased possibility of recurrence. Patients receiving neoadjuvant treatment for CRLMs may have better survival chances after resecting all the DLM sites, either identifiable intraoperatively or not.

Optimal treatment strategies for borderline resectable liver metastases from colorectal cancer

BACKGROUND

Traditionally, colorectal liver metastases (CRLMs) are divided into "initially resectable" and "initially unresectable." The terminology "borderline resectable" continues to be elusive without any common consensus or definition. This narrative review aims to decode the conundrum of "borderline resectable CRLM (BR-CRLM)" and to discuss optimal treatment strategies.

METHODS

A comprehensive review was performed using Medline/PubMed and Web of Science databases with a search period ending on January 1, 2024. Using PubMed, the terms "CRLM," "BR-CRLM," and "management of BR-CRLM" were searched.

RESULTS

The 2016 European Society for Medical Oncology guidelines defined the term "resectability" in CRLM using the "technical (surgical) criteria" and the "oncologically criteria." These 2 criteria form the basis of defining BR-CRLM. Thus, BR-CRLM can be either technically easy but with unfavorable oncologically criteria or technically difficult with favorable oncologically criteria. Although defining BR-CRLM by incorporating both these criteria seems to be the most logical way forward, there is currently a lot of heterogeneity in the literature. It is generally agreed upon that some form of chemotherapy needs to be administered in BR-CRLM before embarking on surgery. Conversion chemotherapy is used in patients with BR-CRLM in which there is a possibility of resection after effective downsizing. Along with improved effective chemotherapy, great strides have been made in pushing the limits of surgery to achieve resectability in this subset of patients.

CONCLUSION

Advanced surgical techniques and locoregional liver-directed therapies coupled with perioperative chemotherapy with or without targeted therapy have made long-term survival benefit, a reality in patients with BR-CRLM. Thus, the time has come to recognize "BR-CRLM" as a distinct entity.

Onyx®, A New Tool for Intraoperative Localization of Liver Lesions

BACKGROUND

Precise preoperative localization of liver tumors facilitates successful surgical procedures, Intraoperative ultrasonography is a sensitive imaging modality. However, the presence of small non-palpable isoechoic intraparenchymal lesions may be challenging intraoperatively.

METHODOLOGY AND MATERIAL DESCRIPTION

Onyx® is a non-adhesive liquid agent comprised of ethylene-vinyl alcohol usually used dissolved in dimethyl-sulfoxide and suspended micronized tantalum powder to provide contrast for visualization under fluoroscopy and ultrasonography and a macroscopic black shape. This embolization material has been increasingly used for the embolization of intracranial arteriovenous malformations. We present the novel application of Onyx® on liver surgery.

CURRENT STATUS

We present the case of a female, 55 years-old, whose medical history revealed an elective sigmoidectomy (pT3N1a). After 17 months of follow up, by PET-CT scan, the patient was diagnosed of a small intraparenchymal hypo-attenuated 13 mm tumor located at segment V consistent with metachronous colorectal liver metastasis. Open metastasectomy was performed, ultrasonography-guided Onyx® infusion was delivered the day after, intraoperative ultrasonography showed a palpable hyperechoic material with a posterior acoustic shadowing artifact around the lesion. Onyx® is a promising new tool, without any previous application on liver surgery, feasible with advantages in small not palpable intraparenchymal liver lesions.

Prospective Exploratory Phase I Clinical Trial Assessing the Safety of Preoperative Marking for Small Liver Tumors

Background Small tumors in liver cirrhosis are difficult to distinguish using intraoperative ultrasonography. In addition, preoperative chemotherapy for metastatic liver cancer may diminish tumor size, thus making tumors difficult to identify intraoperatively. To address such difficulties, we devised a method to mark liver tumors preoperatively to facilitate intraoperative identification. This study aimed to investigate the safety of a preoperative liver tumor marking method. Methodology This exploratory prospective clinical trial included patients with liver tumors measuring ≤20 mm requiring resection. Preoperative marking was performed by placing a coil for embolization of blood vessels near the tumor using either the transcatheter or percutaneous approach. The tumor was identified and resected by intraoperative ultrasonography based on the marker. The study was registered in the University Hospital Medical Information Network Clinical Trials Registry (UMIN000028608). Results Overall, 19 patients (9 with primary liver cancer and 10 with metastatic tumors) were recruited. The transcatheter and percutaneous methods were used in 13 and 6 patients, respectively. Marking was not possible in two patients in the transcatheter group because the catheter could not be guided to the vicinity of the tumor. There were no marking-related complications. Hepatectomy was performed in all but one patient who was not fit for hepatectomy owing to the development of a metastatic liver tumor. The markers were adequately identified during hepatectomy. Additionally, there were no difficulties in the surgical procedure or postoperative complications. Conclusions Preoperative marking with embolization coils can be performed safely for intraoperative identification of liver nodules.

Preoperative percutaneous or transvascular marking for curative resection of small liver tumours with potential for missing during hepatectomy: a study protocol for an open-label, single-arm phase II study

INTRODUCTION

Small liver tumours are difficult to identify during hepatectomy, which prevents curative tumour excision. Preoperative marking is a standard practice for small, deep-seated tumours in other solid organs; however, its effectiveness for liver tumours has not been validated. The objective of this study is to evaluate the effectiveness of preoperative markings for curative resection of small liver tumours.

METHODS AND ANALYSIS

This is an open-label, single-arm, single-centre, phase II study. Patients with liver tumours of ≤15 mm requiring hepatectomy will be enrolled and will undergo preoperative marking by placing a microcoil near the tumour using either the percutaneous or transvascular approach. The tumours, including the indwelling markers, will be excised. The primary endpoint will be the successful resection rate of liver tumours, defined as achieving a surgical margin of ≥5 mm and ≤15 mm. Secondary endpoints will include the results of preoperative marking and hepatectomy.

ETHICS AND DISSEMINATION

Ethical approval for this trial was obtained from the Ethical Committee for Clinical Research of Hiroshima University, Japan. The results will be published at an academic conference or by submitting a paper to a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

jRCTs062220088.

Disappearing Colorectal Liver Metastases: Do We Really Need a Ghostbuster?

The development of new systemic treatment strategies has resulted in a significant increase in the response rates of colorectal liver metastases (CRLM) in the last few years. Although the radiological response is a favorable prognostic factor, complete shrinkage of CRLM, known as disappearing liver metastases (DLM), presents a therapeutic dilemma, and proper management is still debated in the literature. In fact, DLM is not necessarily equal to cure, and when resected, pathological examination reveals in more than 80% of patients a variable percentage of the tumor as residual disease or early recurrence in situ. Moreover, while a higher incidence of intrahepatic recurrence is documented in small series when surgery is avoided, its clinical significance for long-term OS is still under investigation. In light of this, a multidisciplinary approach and, in particular, radiologists’ role is needed to assist the surgeon in the management of DLM, thanks to emerging technology and strategy. Therefore, the aim of this review is to provide an overview of the DLM phenomenon and current management.

Image-guided marking techniques in interventional radiology: A review of current evidence

Precise marking of lesions using image-guided techniques is essential, as imprecise targeting of a tumor can result in either insufficient excision/treatment with an increased risk of recurrence, or excessive removal of healthy tissue. Most frequent indications include localization of nonpalpable lesions before surgical resection (i.e., hook-wire localization of pulmonary nodules before video-assisted thoracoscopy) and definite marking of liver metastasis before neoadjuvant therapy. Other indications include marking of hepatocellular carcinomas that are not visible on ultrasound and unenhanced computed tomography before thermal ablation, of bone lesions before surgical excision, and of different visceral tumors before stereotactic radiotherapy. This review presents the different existing indications, assesses their usefulness, gives systematic details on the technique and lastly analyzes the current literature with emphasis on results and complications.

Management of disappearing colorectal liver metastases: an international survey

BACKGROUND

Improved chemotherapy response rates have lead to "disappearing" colorectal liver metastases (dCRLM). We aim to assess management patterns of dCRLM from an international body of hepatobiliary surgeons.

METHODS

A survey was designed, tested for item relevance, readability and content validity, and distributed to the AHPBA, IHPBA and ANZHPBA.

RESULTS

The majority of 226 respondents were <15 years from training (69%), practiced in academia (82%) and devoted >50% of their practice to hepatobiliary (75%). Surgeons utilize CT(45%) or MRI(47%) for preoperative planning with a preferred imaging interval of <6 weeks. Nearly all have experienced dCRLM (99%) and 63% of surgeons have waited a few months to assess for durability of response prior to definitive surgical/ablative therapy. Only 24% place fiducial markers for lesions <1-cm prior to neoadjuvant chemotherapy. Intra-operatively, 97% of surgeons perform ultrasound, and 71% ablation. When a tumor has "disappeared," 49% elect for observation and 31% resect if the dCRLM is superficial. Of those electing observation, 87% believe there is effective treatment with progression on surveillance imaging.

CONCLUSIONS

Nearly all surgeons have experienced dCRLM with half choosing observation over intervention due to the belief that these lesions may be re-addressed in the future.

Colorectal liver metastases: Current management and future perspectives

The liver is the commonest site of metastatic disease for patients with colorectal cancer, with at least 25% developing colorectal liver metastases (CRLM) during the course of their illness. The management of CRLM has evolved into a complex field requiring input from experienced members of a multi-disciplinary team involving radiology (cross sectional, nuclear medicine and interventional), Oncology, Liver surgery, Colorectal surgery, and Histopathology. Patient management is based on assessment of sophisticated clinical, radiological and biomarker information. Despite incomplete evidence in this very heterogeneous patient group, maximising resection of CRLM using all available techniques remains a key objective and provides the best chance of long-term survival and cure. To this end, liver resection is maximised by the use of downsizing chemotherapy, optimisation of liver remnant by portal vein embolization, associating liver partition and portal vein ligation for staged hepatectomy, and combining resection with ablation, in the context of improvements in the functional assessment of the future remnant liver. Liver resection may safely be carried out laparoscopically or open, and synchronously with, or before, colorectal surgery in selected patients. For unresectable patients, treatment options including systemic chemotherapy, targeted biological agents, intra-arterial infusion or bead delivered chemotherapy, tumour ablation, stereotactic radiotherapy, and selective internal radiotherapy contribute to improve survival and may convert initially unresectable patients to operability. Currently evolving areas include biomarker characterisation of tumours, the development of novel systemic agents targeting specific oncogenic pathways, and the potential re-emergence of radical surgical options such as liver transplantation.