Unique site- and time-specific patterns of recurrence following resection of colorectal carcinoma hepatic metastases in patients staged by FDG-PET

Preoperative and postoperative predictive models of early recurrence for colorectal liver metastases following chemotherapy and curative-intent one-stage hepatectomy

INTRODUCTION

Accurate prediction of patients at risk for early recurrence (ER) among patients with colorectal liver metastases (CRLM) following preoperative chemotherapy and hepatectomy remains limited.

METHODS

Patients with CRLM who received chemotherapy prior to undergoing curative-intent resection between 2000 and 2020 were identified from an international multi-institutional database. Multivariable Cox regression analysis was used to assess clinicopathological factors associated with ER, and an online calculator was developed and validated.

RESULTS

Among 768 patients undergoing preoperative chemotherapy and curative-intent resection, 128 (16.7 %) patients had ER. Multivariable Cox analysis demonstrated that Eastern Cooperative Oncology Group Performance status ≥1 (HR 2.09, 95%CI 1.46-2.98), rectal cancer (HR 1.95, 95%CI 1.35-2.83), lymph node metastases (HR 2.39, 95%CI 1.60-3.56), mutated Kirsten rat sarcoma oncogene status (HR 1.95, 95%CI 1.25-3.02), increase in tumor burden score during chemotherapy (HR 1.51, 95%CI 1.03-2.24), and bilateral metastases (HR 1.94, 95%CI 1.35-2.79) were independent predictors of ER in the preoperative setting. In the postoperative model, in addition to the aforementioned factors, tumor regression grade was associated with higher hazards of ER (HR 1.91, 95%CI 1.32-2.75), while receipt of adjuvant chemotherapy was associated with lower likelihood of ER (HR 0.44, 95%CI 0.30-0.63). The discriminative accuracy of the preoperative (training: c-index: 0.77, 95%CI 0.72-0.81; internal validation: c-index: 0.79, 95%CI 0.75-0.82) and postoperative (training: c-index: 0.79, 95%CI 0.75-0.83; internal validation: c-index: 0.81, 95%CI 0.77-0.84) models was favorable (https://junkawashima.shinyapps.io/CRLMfollwingchemotherapy/).

CONCLUSIONS

Patient-, tumor- and treatment-related characteristics in the preoperative and postoperative setting were utilized to develop an online, easy-to-use risk calculator for ER following resection of CRLM.

Prognostic factors associated with early recurrence following liver resection for colorectal liver metastases: a systematic review and meta-analysis

BACKGROUND

Colorectal cancer (CRC) is the 3rd most common malignancy with the liver being the most common site of metastases. The recurrence rate of colorectal liver metastases (CRLM) after liver resection (LR) is notably high, with an estimated 40% of patients experiencing recurrence within 6 months. In this context, we conducted a meta-analysis to synthesize and evaluate the reliability of evidence pertaining to prognostic factors associated with early recurrence (ER) in CRLM following LR.

METHODS

Systematic searches were conducted from the inception of databases to July 14, 2023, to identify studies reporting prognostic factors associated with ER. The Quality in Prognostic Factor Studies (QUIPS) tool was employed to assess risk-of-bias for included studies. Meta-analysis was then performed on these prognostic factors, summarized by forest plots. The grading of evidence was based on sample size, heterogeneity, and Egger's P value.

RESULTS

The study included 24 investigations, comprising 12705 individuals, during an accrual period that extended from 2007 to 2023. In the evaluation of risk-of-bias, 22 studies were rated as low/moderate risk, while two studies were excluded because of high risk. Most of the studies used a postoperative interval of 6 months to define ER, with 30.2% (95% confidence interval [CI], 24.1-36.4%) of the patients experiencing ER following LR. 21 studies were pooled for meta-analysis. High-quality evidence showed that poor differentiation of CRC, larger and bilobar-distributed liver metastases, major hepatectomy, positive surgical margins, and postoperative complications were associated with an elevated risk of ER. Additionally, moderate-quality evidence suggested that elevated levels of carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA199), lymph node metastases (LNM) of CRC, and a higher number of liver metastases were risk factors for ER.

CONCLUSION

This review has the potential to enhance the efficacy of surveillance strategies, refine prognostic assessments, and guide judicious treatment decisions for CRLM patients with high risk of ER. Additionally, it is essential to undertake well-designed prospective investigations to examine additional prognostic factors and develop salvage therapeutic approaches for ER of CRLM.

[18F]Fluorodeoxyglucose PET for Interventional Oncology in Liver Malignancy

[(18)F]Fluorodeoxyglucose (FDG) PET is a functional imaging tool that provides metabolic information, which has the potential to detect a lesion before it becomes anatomically apparent. This ability constitutes a strong argument for using FDG-PET/computed tomography (CT) in the management of oncology patients. Many studies have investigated the accuracy of FDG-PET or FDG-PET/CT for these purposes, but with small sample sizes based on retrospective cohorts. This article provides an overview of the role of FDG-PET or FDG-PET/CT in patients with liver malignancies treated by means of surgical resection, ablative therapy, chemoembolization, radioembolization, and brachytherapy, all being liver-directed oncologic interventions.

Positron emission tomography and colorectal cancer

Colorectal cancer (CRC) is a major cause of cancer-related morbidity and mortality. Molecular imaging using positron emission tomography (PET) is now an integral part of multidisciplinary cancer care. In this review, we discuss the role of PET in CRC including well established indications in the assessment of recurrent disease and emerging applications such as initial staging, monitoring therapy efficacy and using PET for radiotherapy planning. With rapid advancement in imaging technology, we also discuss the future potential of combining PET and magnetic resonance imaging and the use of novel radiotracers.

Fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography predicts extrahepatic metastatic potential of colorectal metastasis: a practical guide for yttrium-90 microsphere liver-directed therapy

The objective of this retrospective study was to assess the likelihood of extrahepatic metastases based on tumor metabolic load index (TMLI) for patients with colorectal liver metastases to determine the potential intermediate endpoint of yttrium-90 (Y-90) microsphere liver-directed therapy. Forty-eight (48) patients with colorectal metastatic cancer of the liver who were referred for Y-90 microsphere therapy and F-18 fluoro-2-deoxy-D-glucose positron emission tomography (PET) imaging were included. All patients had baseline computed tomography, hepatic angiography, and planning intra-arterial technetium-99m macro-aggregated albumin scans. Pretreatment PET images were analyzed by visual inspection of extrahepatic metastases and by computer quantification of total liver tumor metabolism. For each patient, regions of interest were drawn along the liver edge to measure total liver standard uptake value on axial images, covering the entire span of the liver. The total liver standard uptake value was then converted by logarithm in equivalent volumes of liver mass to obtain TMLI for comparison. A Levene test for equality of variances and t-tests were used for comparing pretreatment TMLIs of patients with or without extrahepatic metastasis. Discriminant and receiver operating characteristic (ROC) analyses were used to obtain a cutoff value with highest specificity in predicting negative extrahepatic metastasis. There were 21 and 27 patients identified as negative and positive for extrahepatic metastasis, respectively. The TMLI of the group with negative extrahepatic metastasis was significantly lower than that with positive extrahepatic metastasis (10.22 + 0.32 versus 10.74 + 0.57, p < 0.0005). The cutoff TMLI with 100% specificity was found to be 10.65. There was a significant difference in liver tumor load with respect to the presence or absence of an extrahepatic metastatic tumor as evaluated objectively with PET. This leads to the identification of TMLI threshold, below which extrahepatic metastases are unlikely and thus may provide guidance for Y-90 therapy.

Nonsurgical options for hepatocellular carcinoma: evolving role of external beam radiotherapy

BACKGROUND

Hepatocellular carcinoma (HCC) is the sixth most common cancer worldwide and thus poses a global concern. Its incidence is expected to increase in North America secondary to the increasing incidence of patients who develop hepatitis C. Patients who ultimately develop cirrhosis have an increased risk of developing hepatocellular carcinoma.

METHODS

The authors focus on nonsurgical therapies for this disease with an exploration of how external beam radiotherapy can be used alone or with other modalities. The development of partial liver strategies secondary to an explosion in radiation treatment planning and delivery advances is reviewed. Integration of advanced technology has evolved from three-dimensional conformal treatment to intensity-modulated radiation therapy and image-guided radiation therapy, along with stereotactic body radiation therapy, tomotherapy, and proton beam therapy.

RESULTS

Current data show a promising future for treatment strategies incorporating radiation with high rates of infield tumor control and low rates of radiation-induced liver disease. Radiation can be delivered in conjunction with transarterial catheter embolization for advanced-stage patients. External beam radiotherapy also has a role in the setting of patients with macrovascular tumor thrombus.

CONCLUSIONS

Future directions include how to best synergize the effects of radiation strategies with novel agents, given the hypervascularity of HCC. Downstaging of larger lesions with these therapies to resectable or transplantable disease may lead to better outcomes for patients deemed inoperable at diagnosis, and definitive radiotherapy may offer cure to patients with smaller lesions.

Systemic therapy for advanced hepatocellular carcinoma: past, present, and future

BACKGROUND

Although approximately 80% of hepatocellular carcinoma (HCC) cases occur in developing countries, the incidence of HCC in Western countries is on the rise due to the impact of hepatitis C. Challenges in developing effective therapies include the inherent chemoresistance of HCC, the pharmacologic challenges presented by a diseased liver, the presentation of most patients at advanced stages, and the difficulty in adequately measuring radiological response. While responses to traditional chemotherapeutic agents have been documented, significant survival benefit is debatable.

METHODS

The authors review the results of published clinical trials of systemic therapy and immunotherapy that have impacted the present treatment of HCC.

RESULTS

With recent progress in the elucidation of HCC molecular pathways, targeted agents show promise. The multikinase inhibitor sorafenib has provided survival benefit in patients with advanced HCC and well-preserved liver function. Sunitinib, bevacizumab, epidermal growth factor receptor inhibitors, and mammalian target of rapamycin (mTOR) inhibitors have shown activity in small patient cohorts. Immunotherapy appears to be a promising approach that can result in the regression of bulky, invasive cancer in some patients.

CONCLUSIONS

New agents with a variety of mechanisms of activity offer promising therapeutic options for patients with advanced HCC.

Surgery for colorectal liver metastases

In this review the surgery of colorectal liver metastases is discussed. It has long been known that liver surgery can cure metastatic colorectal cancer although in only a small proportion of the population with the disease. However with better understanding of the natural history of the condition and advances in technique more patients can have safe, potentially curative surgery. The multidiscipline management of patients with effective chemotherapy has led to more patients benefiting from surgery after reducing the size of the metastases and allowing operation on patients who were previously inoperable. Chemotherapy also improves at least the medium-term outcome in those who are operable at the outset. Minimally invasive techniques have been developed so that major hepatectomy may be accomplished in up to half of such cases with a very short hospital stay and limited interference with quality of life. Lastly, using portal vein embolisation to cause hypertrophy of the future liver remnant and on occasions combining it with staged liver resection allows potentially curative surgery on patients who previously could not have survived resection. These developments have led to more patients being cured of advanced colorectal cancer.