Debulking Hepatectomy for Colorectal Liver Metastasis Conveys Survival Benefit

(1) Background: Despite advances in surgical technique and systemic chemotherapy, some patients with multifocal, bilobar colorectal liver metastases (CRLM) remain unresectable. These patients may benefit from surgical debulking of liver tumors in combination with chemotherapy compared to chemotherapy alone. (2) Methods: A retrospective study including patients evaluated for curative intent resection of CRLM was performed. Patients were divided into three groups: those who underwent liver resection with recurrence within 6 months (subtotal debulked, SD), those who had the first stage only of a two-stage hepatectomy (partially debulked, PD), and those never debulked (ND). Kaplan-Meier survival curves and log-rank test were performed to assess the median survival of each group. (3) Results: 174 patients underwent liver resection, and 34 patients recurred within 6 months. Of the patients planned for two-stage hepatectomy, 35 underwent the first stage only. Thirty-two patients were never resected. Median survival of the SD, PD, and ND groups was 31 months, 31 months, and 19.5 months, respectively (p = 0.012); (4) Conclusions: Patients who underwent a debulking of CRLM demonstrated a survival benefit compared to patients who did not undergo any surgical resection. This study provides support for the evaluation of intentional debulking versus palliative chemotherapy alone in a randomized trial.

Targeting Liver Metastases to Potentiate Immunotherapy in MS-Stable Colorectal Cancer-A Review of the Literature

Immunotherapy has revolutionized the treatment of several cancers, including melanoma and lung cancer. However, for colorectal cancer, it is ineffective for 95% of patients with microsatellite-stable disease. Recent evidence suggests that the liver's immune microenvironment plays a pivotal role in limiting the effectiveness of immunotherapy. There is also evidence to show that targeting liver metastases with locoregional therapies, such as surgery or irradiation, could potentiate immunotherapy for these patients. This review presents evidence from preclinical studies regarding the underlying mechanisms and from clinical studies that support this approach. Furthermore, we outline potential directions for future clinical trials. This innovative strategy could potentially establish immunotherapy as an effective treatment for MS-stable colorectal cancer patients, which are currently considered resistant.

Abstract 4601: Vitamin D supplementation attenuates resistance to anti-angiogenic therapy in colorectal cancer liver metastases

Colorectal cancer liver metastasis (CRCLM) is one of the deadliest cancers. CRCLM tumours have two distinct histopathological growth patterns (HGPs) including desmoplastic HGP (DHGP) and replacement HGP (RHGP). The DHGP tumours are angiogenic, while their RHGP counterparts are vessel co-opting. The patients with RHGP tumours showed poor response to anti-angiogenic agents, as well as a worse prognosis. Herein, we conducted a retrospective cohort study that comprised 106 CRCLM patients to examine the effect of vitamin D supplementation on the HGPs of the tumours and the 5-year overall survival (OS). Interestingly, we found an inverse correlation between vitamin D supplementation and the presence of RHGP tumours in CRCLM patients. Additionally, the population who used vitamin D supplementation had significantly better 5-year OS. Moreover, our in vivo results suggested that vitamin D supplementation significantly improves the response of CRCLM tumours to anti-angiogenic therapy. Mechanistically, we found that vitamin D can suppress cancer cell motility, which is essential for the development of vessel co-option tumours and resistance to anti-angiogenic therapy. Collectively, this study suggests vitamin D supplementation is a promising way to attenuate resistance to anti-angiogenic therapy and improve the prognosis of CRCLM patients.

Citation Format: Miran Rada, Lucyna Krzywon, Audrey Kapelanski-Lamoureux, Stephanie Petrillo, Anthoula Lazaris, Peter Metrakos. Vitamin D supplementation attenuates resistance to anti-angiogenic therapy in colorectal cancer liver metastases. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 4601.

A Retrospective Study on the Role of Metformin in Colorectal Cancer Liver Metastases

Colorectal cancer liver metastases (CRCLMs) have two main histopathological growth patterns (HPGs): desmoplastic (DHGP) and replacement (RHGP). The vascularization in DHGP tumours is angiogenic, while the RHGP tumours exert vessel co-option vasculature. The presence of vessel co-option tumours is associated with poor response to anti-angiogenic agents and chemotherapy, as well as a worse prognosis. Metformin has been shown to influence the progression and vasculature of tumours in different cancers. However, its role in CRCLM is poorly understood. Herein, we conducted a retrospective cohort study to examine the role of metformin in CRCLM. A dataset of 108 patients was screened, of which 20 patients used metformin. The metformin user patients did not use metformin as an anticancer agent. We noticed a significantly lower percentage of CRCLM patients with vessel co-opting RHGP tumours in the population that used metformin compared to CRCLM patients who did not use metformin. Similar results were obtained when we compared the ratio of recurrence and extrahepatic metastases incidence. Moreover, the metformin user patients had significantly higher survival outcome compared to nonusers. Collectively, our data suggest that metformin administration is likely associated with better prognosis of CRCLM.

AI-powered multi-omic signature to predict treatment response of patients with colorectal cancer liver metastasis

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Background: Colorectal cancer (CRC) is the third leading cause of cancer-related deaths in North America with over 50% of CRC patients developing liver metastases (LM) and 90% will die from metastatic disease. CRCLM are categorized into two main histological growth patterns (HGP) lesions: Desmoplastic (DHGP) and Replacement (RHGP). We have previously published that HGPs display distinct patterns of vascularization, local invasion, growth and response to treatment. Resected CRCLM patients with predominantly DHGP metastasis (~45%) receiving anti-VEGF therapy and chemotherapy have more than double the 5-year overall survival compared to patients with RHGP (~55%) who have received the same treatment. We are therefore treating patients that will not respond and should in fact be managed differently. Currently, there are no available biomarkers or stratification tools that predict colorectal cancer liver metastasis response to therapy. Methods: In collaboration with My Intelligent Machines (MIMs’), we used a proprietary GI2 (Genetic Interaction Graph Inference) algorithm inferring genetic interactions. We developed an AI based pipeline to develop a multi-modality signature, based on blood test analysis, to identify CRCLM patients who will 1) respond to Angiogenic Inhibitor-based therapies and 2) monitor the development of drug resistance (non-responders). Results: We obtained transcriptomic (tumor tissue) as well as proteomic data (liquid biopsy: Extracellular vesicle cargo), linked to clinical data from 40 chemonaïve patients, and fed the data into MIMs platform (BioMark). The software was able to identify differentially expressed genes common to the top differentially enriched proteins leading to a robust liquid biopsy biomarker signature distinguishing DHGP and RHGP. Furthermore, our data demonstrates a unique multi-modality signature providing biological insight for therapeutic failures and/or success. Conclusions: We will use these signatures to not only predict response to treatment but also decipher the molecular mechanisms driving these two phenotypes and identify unique targets. It is expected that this knowledge will lead to optimization of current treatment strategies, allowing for a precision therapy approach to the management of metastatic disease and cost saving for the health care system.

Extended criteria liver resection: Can noncurative intent resection of colorectal liver metastasis improve survival?

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Background: From initially believed to be a palliative diagnosis, CRLM management has ranged from nonoperative, resection of only solitary lesions, resection only if 1 cm margin could be obtained, to major hepatectomies with liver regenerative procedures. With a greater understanding of the disease and advances in systemic therapy, clinicians have been able to continuously push the envelope in both resection and local therapies to improve overall survival in patients with CRLM. The constant evolution of management for CRLM raises the question – would patients benefit from a non-curative intent resection by decreasing overall tumor burden? Is there a role for debulking of disease as an extended criterion to improve median survival? Methods: A retrospective study was conducted by identifying patients who consented to participate in the liver disease biobank research program. Consented patients with CRLM evaluated for a two-stage hepatectomy (TSH) between 2012-2020 were identified. Patients were divided into three groups: those that successfully completed TSH, those that underwent the first stage only of the TSH (surgical debulking + best chemotherapy +/- local ablative therapy), and those that were not resected (best chemotherapy +/- local ablative therapy). Patients that underwent successful completion of TSH were excluded from analysis. Kaplan Meier survival curves and log-rank test were performed to assess the median survival between the surgical debulking + best chemotherapy +/- local ablative therapy and best chemotherapy +/- local ablative therapy groups. Results: Of the 114 patients identified, 47 patients underwent successful completion of TSH, 35 patients underwent the first stage only of the TSH, and 32 patients were eventually deemed unresectable. Reasons for unresectability included intraoperative findings (n = 14), progression of disease on best chemotherapy (n = 8), unresectable extrahepatic disease, local recurrence of primary, or unfit for surgery. Patients who underwent first stage of the TSH and those that were not resected both received best chemotherapy with/without local ablative therapies. 32 of the 35 patients in the surgical debulking + best chemotherapy +/- local ablative therapy group and 27 of 32 patients in the best chemotherapy +/- local ablative therapy group presented with synchronous disease. Tumor volume resected ranged from 5% - 95%. Median survial of the surgical debulking + best chemotherapy +/- local ablative therapy group was 31 months vs 20 months in the best chemotherapy +/- local ablative therapy group (p = 0.029). Conclusions: Patients undergoing incomplete resection of CRLM demonstrated a survival benefit compared to patients who did not undergo any surgical resection. This suggests there may be a potential systemic benefit to reducing overall tumor burden. This preliminary study provides the framework to further explore the systemic effects of surgical debulking of CRLM to improve median survival as an extended criterion for non-curative intent liver resection.

A single center survival analysis of patients with colorectal cancer who underwent next generation sequencing

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Background: Colorectal cancer (CRC) remains a lethal diagnosis with an overall 5-year survival rate of 5-10% for patients with unresectable metastatic disease. The advent of next generation sequencing allows tailored systemic therapy to specific mutations with the goal of improving patient survival. McGill University Health Center instituted next generation sequencing in 2019. Our study aims to evaluate survival outcomes in patients who underwent NGS testing. Methods: A retrospective collection of data on all patients with CRC who were presented at both lower gastroenterology and hepatobiliary tumor boards from January 2019 through July 2022 ( n= 498). Survival and was compared between patients who were found to have genetic alterations identified using the Illumina Miseo platform. Statistical Analysis was performed with GraphPad Prism. Results: A total of 321 (64%) patients had NGS performed on either their primary tumor or a metastasis. A total of 229 (71%) CRC patients had genetic alterations identified on NGS. The most commonly mutated genes were KRAS (41%), APC (17%), PIK3CA (16%) and BRAF (8%). There was no significant difference in median overall survival between patients who had an identified genetic alteration and patients who did not (p = 0.8). Patients with metastatic disease and synchronous presentation had higher rates of genetic alterations (69% and 70%, respectively). Conclusions: This study provides real world data for a single institution initiating Next generation sequencing in colorectal cancer patients. Next Generation testing is an advantageous tool which can help stratify patients into tailored treatment regiments which will lead to improved patient outcomes.

Abstract 5291: Characterizing the interplay between angiogenic and immunoactive factors of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the fourth leading cause of cancer-related death globally. Patients typically present at an advanced stage and less than 50% reach the maximum 1-year survival rate, when given as first-line treatment, Sorafenib. This highlights the need for early detection and novel therapeutic targets crucial to increase overall survival (OS) for patients with HCC. Given the important role of angiogenesis in HCC from its early stage and its rich immune composition, anti-angiogenic and immune checkpoint inhibitors (ICI), are two therapeutic approaches when combined marked the first treatment in more than a decade to significantly improve the overall survival and progression-free survival in patients with advanced HCC compared to Sorafenib. While the combination of agents inhibiting angiogenesis and ICI have recently entered the clinic, the interplay between angiogenic factors and immunity in the context of this approach remains poorly understood. Here we focus on understanding the interplay between the vascular state of the tumor and the immune response in HCC. As a first step, we focus on defining the immune and vasculature landscape of the central tumor, peripheral tumor, adjacent liver to the tumor, and distal liver regions of each lesion by immunohistochemistry (IHC). Forty (40) formalin-fixed paraffin-embedded (FFPE) human liver tissue samples containing untreated and non-viral HCC tumors, obtained from the Liver Disease Biobank of the RI-MUHC were used to perform IHC. Images were viewed and scored using the Aperio ImageScope software. With respect to the vasculature, we observe that all tumors have a combination of both angiogenic (CD34/Ki67+ve) and co-optioning (CD31 +ve) features, with no uniform distribution. Our immune markers demonstrate that both adaptive and innate immune cells are present at the interface and different tumors demonstrate different levels of infiltration. Next, to identify the immune subtype populations (ie macrophage M1 vs M2, Treg, etc) present, we will use the NanoString Whole Transcriptome Atlas spatial profiler technology. We will also then link the vasculature to any specific immune profile. For example, it has been shown in other cancer types that macrophages are associated with co-option. This project presents preliminary evidence for the interaction of vascular factors with immune cells, thus providing insight into the biological rationale of why 30% of patients responded to combined angiogenic and immunotherapy treatment.

Citation Format: Audrey Kapelanski-Lamoureux, Flemming Kondrup, Lucyna Krzywon, Stephanie K. Petrillo, Anthoula Lazaris, Peter Metrakos. Characterizing the interplay between angiogenic and immunoactive factors of hepatocellular carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5291.

Limitations in resectability of colorectal liver metastases 2020 - A systematic approach for clinicians and patients

Colorectal liver metastases (CRLM) affect over 50 % of all patients with colorectal cancer, which is the second leading cause of cancer in the western world. Resection of CRLM may provide cure and improves survival over chemotherapy alone. However, resectability of CLRM has to be decided in multidisciplinary tumor boards and is based on oncological factors, technical factors and patient factors. The advances of chemotherapy lead to the abolition of contraindications to resection in favor of technical resectability, but somatic mutations and molecular subtyping may improve selection of patients for resection in the future. Technical factors center around anatomy of the lesions, volume of the remnant liver and quality of the liver parenchymal. Multiple strategies have been developed to overcome volume limitations and they are reviewed here. The least investigated topic is how to select the right patients among an elderly and frail patient population for the large variety of technical options specifically for bi-lobar CRLM to keep 90-day mortality as low as possible. The review is an overview over the current state-of-the art and a systematic guide to the topic of resectability of CRLM for both clinicians and patients.