Publications by authors named "Chung Yip Chan"
Background: Pure laparoscopic donor hepatectomy (L-DH) has seen a rise in uptake in recent years following the popularization of minimally invasive modality for major hepatobiliary surgery. Our study aimed to determine the safety and compare the perioperative outcomes of L-DH with open donor hepatectomy (O-DH) and laparoscopic non donor hepatectomy (L-NDH) based on our single institution experience.
Methods: Eighty of 113 laparoscopic hemi-hepatectomies performed between 2015 and 2022 met study inclusion criteria.
Background: Liver transplantation remains the optimal treatment for multifocal hepatocellular carcinoma (HCC). However, due to resource constrains, other therapeutic modalities such as liver resection (LR), are frequently utilized. LR, however, has to be balanced against potential morbidity and mortality along with the risks of early recurrence leading to futile surgery.
View Article and Find Full Text PDFBackground: Conventional differential expression (DE) testing compares the grouped mean value of tumour samples to the grouped mean value of the normal samples, and may miss out dysregulated genes in small subgroup of patients. This is especially so for highly heterogeneous cancer like Hepatocellular Carcinoma (HCC).
Methods: Using multi-region sampled RNA-seq data of 90 patients, we performed patient-specific differential expression testing, together with the patients' matched adjacent normal samples.
Introduction: Our primary objective was to determine if receiving intraoperative blood transfusion was a significant prognostic factor for overall and recurrence-free survival after curative resection of hepatic cellular carcinoma (HCC).
Methodology: Between 2001 and 2018, 1092 patients with histologically proven primary HCC who underwent curative liver resection were retrospectively reviewed. Primary study endpoints were recurrence-free survival (RFS) and overall survival (OS).
IL-17-producing CD8 (Tc17) T cells have been shown to play an important role in infection and chronic inflammation, however their implications in hepatocellular carcinoma (HCC) remain elusive. In this study, we performed cytometry by time-of-flight (CyTOF) and revealed the distinctive immunological phenotypes of two IFNγ and IFNγ Tc17 subsets that were preferentially enriched in human HCC. Single-cell RNA-sequencing analysis further revealed regulatory circuits governing the different phenotypes of these Tc17 subsets.
View Article and Find Full Text PDFArticle Synopsis
- This study assessed the effectiveness of robotic versus laparoscopic limited liver resections for tumors in challenging areas of the liver from 2010 to 2019 across 24 centers.
- The analysis included 983 patients and found that robotic techniques led to less blood loss, fewer conversions to open surgery, and shorter operation times compared to laparoscopic techniques.
- Overall, both approaches were deemed safe and effective for removing tumors in the posterosuperior liver segments.
Background: The Memorial Sloan Kettering Cancer Center nomogram, the predictive scoring system of Yamamoto et al, and the 3-point transfusion risk score of Lemke et al are models used to determine the probability of receiving intraoperative blood transfusion in patients undergoing liver resection. However, the external validity of these models remains unknown. The objective of this study was to evaluate their predictive performance in an external cohort of patients with hepatocellular carcinoma.
View Article and Find Full Text PDFObjective: We aimed to prognosticate survival after surgical resection of HCC stratified by stage with amalgamation of the modified Barcelona Clinic Liver Cancer (BCLC) staging system and location of tumour.
Methods: This single-institutional retrospective cohort study included patients with HCC who underwent surgical resection between 1st January 2000 to 30th June 2016. Participants were divided into 6 different subgroups: A-u) Within MC with Unilobar lesions; A-b) Within MC + Bilobar lesions; B1-u) Out of MC + within Up-To-7 + Unilobar lesions; B1-b) Out of MC + within Up-to-7 + Bilobar lesions; B2-u) Out of MC + Out of Up-To-7 + Unilobar lesions; B2-b) Out of MC + Out of Up-To-7 + Bilobar lesions.
Introduction: While minimally invasive liver resections (MILR) have demonstrated advantages in improved post-operative recovery, widespread adoption is hampered by inherent technical difficulties. Our study attempts to analyze the role of anthropometric measures in MILR-related outcomes.
Methods: Between 2012 and 2020, 676 consecutive patients underwent MILR at the Singapore General Hospital of which 565 met study criteria and were included.
Objective: To establish global benchmark outcomes indicators after laparoscopic liver resections (L-LR).
Background: There is limited published data to date on the best achievable outcomes after L-LR.
Methods: This is a post hoc analysis of a multicenter database of 11,983 patients undergoing L-LR in 45 international centers in 4 continents between 2015 and 2020.
Background: Despite the wide use of laparoscopy for liver resection, laparoscopic caudate lobe resections(L-CLR) remain technically challenging, only attempted by experts in the field. The primary objective of this study was to determine the safety and compare the perioperative outcomes of L-CLR with O-CLR based on our single institution experience in a 1:2 propensity score-matched controlled study based on our single institution experience.
Methods: Between 2004 and 2020, 67 consecutive patients who underwent CLR at Singapore General Hospital were identified.
Background: A systematic review and network meta-analysis was performed to compare outcomes after living donor right hepatectomy via the following techniques: conventional open (Open), mini-laparotomy (Minilap), hybrid (Hybrid), totally laparoscopic (Lap), and robotic living donor right hepatectomy (Robotic).
Methods: PubMed, EMBASE, Cochrane, and Scopus were searched from inception to August 2021 for comparative studies of patients who underwent living donor right hepatectomy.
Results: Nineteen studies comprising 2,261 patients were included.
Article Synopsis
- * A study involving 67 patients with hepatocellular carcinoma (HCC) revealed that while genetic variations remained stable across different cancer stages, phenotypic variations quickly increased, especially in stage II patients, often showing multiple transcriptomic subtypes within a single tumor.
- * The findings indicate that phenotypic ITH is a critical factor for predicting patient outcomes and explains why single-target therapies are often ineffective in HCC, stressing the need for more comprehensive studies on phenotypic evolution in various cancers.
Immune evasion is key to cancer initiation and later at metastasis, but its dynamics at intermediate stages, where potential therapeutic interventions could be applied, is undefined. Here we show, using multi-dimensional analyses of resected tumours, their adjacent non-tumour tissues and peripheral blood, that extensive immune remodelling takes place in patients with stage I to III hepatocellular carcinoma (HCC). We demonstrate the depletion of anti-tumoural immune subsets and accumulation of immunosuppressive or exhausted subsets along with reduced tumour infiltration of CD8 T cells peaking at stage II tumours.
View Article and Find Full Text PDFImportance: Laparoscopic and robotic techniques have both been well adopted as safe options in selected patients undergoing hepatectomy. However, it is unknown whether either approach is superior, especially for major hepatectomy such as right hepatectomy or extended right hepatectomy (RH/ERH).
Objective: To compare the outcomes of robotic vs laparoscopic RH/ERH.
Background And Aims: Hypoxia is one of the central players in shaping the immune context of the tumor microenvironment (TME). However, the complex interplay between immune cell infiltrates within the hypoxic TME of HCC remains to be elucidated.
Approach And Results: We analyzed the immune landscapes of hypoxia-low and hypoxia-high tumor regions using cytometry by time of light, immunohistochemistry, and transcriptomic analyses.
Both robotic and laparoscopic right anterior sectionectomy and central hepatectomy can be performed safely in expert centres, with excellent outcomes. The robotic approach was associated with statistically significant less blood loss compared with laparoscopy, although the clinical relevance of this finding remains unclear.
View Article and Find Full Text PDFBackground: The majority of evidence with regards to minimally invasive liver resection (MILR) favors its application in minor hepatectomies. We conducted a propensity score-matched (PSM) analysis to determine its feasibility and safety in major hepatectomies (MIMH) for liver malignancies.
Methods: Retrospective review of 130 patients who underwent MIMH and 490 patients who underwent open major hepatectomy (OMH) for malignant pathologies was performed.
Background: Few studies have evaluated the outcomes of curative liver resection (LR) in octogenarian patients, analysed cancer-specific survival (CSS) with HCC-related death or explored the age-varying effect of HCC-related death in elderly patients undergoing LR. We aim to determine the effect of age on the short and long-term outcomes of LR for HCC.
Methodology: Between 2000 and 2018, 1,092 patients with primary HCC who underwent LR with curative intent were retrospectively reviewed.
Background: The management of HCC differs depending on the extent of disease. Surgery may be offered in selected cases of T4 disease as defined by AJCC 8th. However, outcome data post partial hepatectomy (PH) for T4 disease is scarce.
View Article and Find Full Text PDFBackground: Minimally invasive right posterior sectionectomy (RPS) is a technically challenging procedure. This study was designed to determine outcomes following robotic RPS (R-RPS) and laparoscopic RPS (L-RPS).
Methods: An international multicentre retrospective analysis of patients undergoing R-RPS versus those who had purely L-RPS at 21 centres from 2010 to 2019 was performed.
Background: Therapeutic synergism between radiotherapy and immune checkpoint blockade has been observed in preclinical models of hepatocellular carcinoma. We aimed to study the safety and efficacy of sequential radioembolisation with yttrium-90-resin microspheres (Y90-radioembolisation) followed by nivolumab in patients with advanced hepatocellular carcinoma.
Methods: Patients with Child-Pugh A cirrhosis and advanced hepatocellular carcinoma not suitable for curative surgery were treated with Y90-radioembolisation followed by intravenous nivolumab 240 mg 21 days after Y90-radioembolisation and every 2 weeks thereafter.
Background: Minimally invasive distal pancreatectomy (MIDP) is being adopted increasingly worldwide. This study aimed to compare the short-term outcomes of patients who underwent MIDP versus open distal pancreatectomy (ODP).
Methods: A retrospective review of all patients who underwent a DP in our institution between 2005 and 2019 was performed.
Introduction: We performed this study in order to investigate the impact of tumour size on the difficulty of MILR, as well as to elucidate the optimal tumour size cut-off/s to distinguish between 'easy' and 'difficult' MILRs.
Materials And Methods: This is retrospective review of 603 consecutive patients who underwent MILR between 2006 and 2019 of which 461 met the study inclusion criteria. We first conducted an exploratory analysis to visualize the associations between tumor size and various surrogates of laparoscopic difficulty in order to determine to optimal tumor size cutoff for stratification.
Background: Presently, data on the impact of enhanced recovery protocols on the outcomes of laparoscopic liver resection remain limited. We performed propensity matched analysis comparing the outcomes between patients undergoing laparoscopic liver resection before and after the introduction of an enhanced recovery protocol.
Methods: Between 2013 and 2019, 462 consecutive patients underwent laparoscopic liver resection by 3 surgeons of which 360 met the study inclusion criteria.