Ser-Yee Lee

Importance of tumor size as a prognostic factor after partial liver resection for solitary hepatocellular carcinoma: Implications on the current AJCC staging system

Background Presently, the impact of tumors size as a prognostic factor after curative liver resection (LR) for solitary hepatocellular carcinoma (HCC) remains controversial. This study was performed to determine the prognostic factors of patients undergoing LR for solitary HCC with special emphasis on the importance of tumor size. Methods Between 2000 and 2013, 560 patients underwent curative LR for solitary primary HCC which met the study criteria. Results One-hundred and seventy-eight patients underwent major hepatectomies and the overall in-hospital mortality was 2.0%. There were 282 patients (50.4%) with liver cirrhosis. The 5-year overall survival (OS) was 64% and recurrence free survival (RFS) was 50%, respectively. Multivariate analyses demonstrated that cirrhosis, microvascular invasion and size were independent predictors of RFS and cirrhosis, microvascular invasion and age were independent prognostic factors of OS. Subset analysis demonstrated that tumor size was a prognostic factor for solitary HCC with microvascular invasion (AJCC T2) but not solitary HCC without microvascular invasion (AJCC T1). Conclusions Size, microvascular invasion, and cirrhosis are independent prognostic factors of RFS for solitary HCC after LR. Tumor size is an important prognostic factor in T2 but not T1 solitary tumors. These findings suggest that the current AJCC TNM staging system may need to be revised. J. Surg. Oncol.

Significance of neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio and prognostic nutrition index as preoperative predictors of early mortality after liver resection for huge (≥10 cm) hepatocellular carcinoma

This study aimed to determine preoperative predictors of early (<1 year) mortality from disease recurrence after liver resection (LR) for huge (≥10 cm) HCC, with special emphasis on the importance of neutrophil‐to‐lymphocyte ratio (NLR), platelet‐to‐lymphocyte ratio (PLR), and prognostic nutrition index (PNI).

Are preoperative blood neutrophil‐to‐lymphocyte and platelet‐to‐lymphocyte ratios useful in predicting malignancy in surgically‐treated mucin‐producing pancreatic cystic neoplasms?

The aim of this study was to determine if neutrophil‐to‐lymphocyte ratio (NLR) and platelet‐to‐lymphocyte ratio (PLR) were predictive of malignancy in mucin‐producing pancreatic cystic neoplasms (MpPCN).Introduction The aim of this study was to determine if neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) were predictive of malignancy in mucin-producing pancreatic cystic neoplasms (MpPCN). Methods One hundred and twenty patients with MpPCN were retrospectively reviewed. Malignant neoplasms were defined as neoplasms harbouring invasive carcinoma or high grade dysplasia. A high NLR and PLR were defined as ≥2.551 and ≥208.1, respectively. Results High NLR was significantly associated with symptomatic tumors, larger tumors, solid component, main-duct IPMN, and Sendai high risk category. High PLR was significantly associated with jaundice and Sendai high risk category. On univariate analyses, symptomatic tumors, jaundice, solid component, dilated pancreatic duct, and both a high NLR and PLR were significant predictors of malignant and invasive MpPCN. On multivariate analyses, solid component and dilated pancreatic duct were independent predictors of malignant and invasive MpPCN. PLR was an independent predictor for invasive MpPCN. When MpPCN were stratified by the Fukuoka and Sendai Guidelines, both a high NLR and PLR were significantly associated with malignant neoplasms within the high risk categories. Conclusions PLR is an independent predictor of invasive carcinoma. The addition of PLR as a criterion to the FCG and SCG significantly improved the predictive value of these guidelines in detecting invasive neoplasms. J. Surg. Oncol. 2015; 112:366–371.

Laparoscopic Liver Resection for Tumors in the Left Lateral Liver Section.

Background: The laparoscopic approach is increasingly adopted for liver resections today especially for lesions located in the left lateral liver section. This study was conducted to determine the impact of the introduction of laparoscopic liver resection (LLR) as a surgical option for suspected small- to medium-sized (<8 cm) tumors located in the left lateral section (LLS). Methods: This is a retrospective review of 156 consecutive patients who underwent LLR or open liver resection (OLR) of tumors located in the LLS. The study was divided into 2 consecutive periods (period 1, January 2003 through September 2006, and period 2, October 2006 through April 2014); LLR was available as a surgical option only in the latter period. Comparisons made were LLR versus OLR, LLR versus OLR (in period 2 only), and resections performed in period 1 versus period 2. Results: Forty-two patients underwent LLR with 4 conversions. LLR was significantly associated with a longer median operative time [167.5 minutes (range, 60–525) vs 105 minutes (range, 40–235); P < .001], decreased need for the Pringle maneuver [n = 1 (2%) vs 22 (19%); P = .008], and shorter postoperative stay [n = 4 (range, 1–10) days vs 5 days (range, 2–47); P < .001] compared with open resection. Comparison of the 42 patients who underwent LLR with the 64 contemporaneous patients who underwent OLR demonstrated similar outcomes. Again, LLR was associated with a significantly longer operation, decreased need for the Pringle maneuver, and shorter hospital stay. Conclusions: LLR can be safely adopted to treat lesions in the LLS. The procedure is associated with a shorter postoperative stay and a decreased need for the Pringle maneuver, but longer operative time compared with that required for OLR.

Laparoscopic repeat liver resection for recurrent hepatocellular carcinoma

Repeat liver resection is effective for recurrent hepatocellular carcinoma (rHCC). This study aimed to determine the outcomes of laparoscopic repeat liver resection (LRLR) for rHCC.

Robotic hepatectomy: initial experience of a single institution in Singapore

INTRODUCTION In this study, we report our initial experience with robotic hepatectomy. METHODS Consecutive patients who underwent robotic hepatectomy at Singapore General Hospital, Singapore, from February 2013 to February 2015 were enrolled in this study. The difficulty level of operations was graded using a novel scoring system for laparoscopic hepatectomies. RESULTS During the two-year period, five consecutive robotic hepatectomies were performed (one left lateral sectionectomy, one non-anatomical segment II/III resection, one anatomical segment V resection with cholecystectomy, one extended right posterior sectionectomy and one non-anatomical segment V/VI resection). Two hepatectomies were performed for suspected hepatocellular carcinoma, two for solitary liver metastases and one for a large symptomatic haemangioma. The median age of the patients was 53 (range 38-66) years and the median tumour size was 2.5 (range 2.1-7.3) cm. The median total operation time was 340 (range 155-825) minutes and the median volume of blood loss was 300 (range 50-1,200) mL. There were no open conversions and no mortalities or major morbidities (> Clavien-Dindo Grade II). The difficulty level of the operations was graded as low in one case (Score 2), intermediate in three cases (Score 5, 6 and 6) and high in one case (Score 10). There was one minor morbidity, where the patient experienced Grade A bile leakage, which resolved spontaneously. The median length of postoperative hospital stay was 5 (range 4-7) days. CONCLUSION Our initial experience confirmed the feasibility and safety of robotic hepatectomy.

Critical appraisal of the impact of individual surgeon experience on the outcomes of laparoscopic liver resection in the modern era: collective experience of multiple surgeons at a single institution with 324 consecutive cases

BackgroundMost studies analyzing the learning experience of laparoscopic liver resection (LLR) focused on the experience of one or two expert pioneering surgeons. This study aims to critically analyze the impact of individual surgeon experience on the outcomes of LLR based on the contemporary collective experiences of multiple surgeons at single institution.MethodsRetrospective review of 324 consecutive LLR from 2006 to 2016. The cases were performed by 10 surgeons over various time periods. Four surgeons had individual experience with <20 cases, four surgeons with 20–30 cases, and two surgeons with >90 cases. The cohort was divided into two groups: comparing a surgeon’s experience between the first 20, 30, 40, and 50 cases with patients treated thereafter. Similarly, we performed subset analyses for anterolateral lesions, posterosuperior lesions, and major hepatectomies.ResultsAs individual surgeons gained increasing experience, this was significantly associated with older patients being operated, decreased hand-assistance, larger tumor size, increased liver resections, increased major resections, and increased resections of tumors located at the posterosuperior segments. This resulted in significantly longer operation time and increased use of Pringle maneuver but no difference in other outcomes. Analysis of LLR for tumors in the posterosuperior segments demonstrated that there was a significant decrease in conversion rates after a surgeon had experience with 20 LLR. For major hepatectomies, there was a significant decrease in morbidity, mortality, and length of stay after acquiring experience with 20 LLR.ConclusionLLR can be safely adopted today especially for lesions in the anterolateral segments. LLR for lesions in the difficult posterosuperior segments and major hepatectomies especially in cirrhosis should only be attempted by surgeons who have acquired a minimum experience with 20 LLR.

Validation and comparison between current prognostication systems for pancreatic neuroendocrine neoplasms: A single-institution experience with 176 patients

Background. This article aims to validate and compare the performance of 6 prognostication systems—the World Health Organization 2010 grading criteria, the European Neuroendocrine Tumour Society and the American Joint Committee for Cancer staging systems, the Memorial Sloan Kettering Cancer Center staging and grading systems, as well as the Bilimoria criteria in a cohort of patients with pancreatic neuroendocrine neoplasms at a single institution. Methods. A retrospective review of 176 patients with histologically proven pancreatic neuroendocrine neoplasm was performed. The prognostic ability of the various prognostication systems for pancreatic neuroendocrine neoplasm was assessed by analyzing the homogeneity, discriminatory ability, monotonicity of gradient, and Akaike information criteria. Results. The 5‐year overall survival for the 176 patients was 69% and 5‐year recurrence‐free survival in 119 patients who underwent curative resection was 78%. Comparison between the 6 prognostication systems demonstrated that the World Health Organization 2010 system had the lowest Akaike information criteria score and was hence the best prognostication system in predicting overall survival and recurrence‐free survival rates in our cohort of patients. The European Neuroendocrine Tumour Society was superior to the American Joint Committee for Cancer in prognosticating overall survival rates for pancreatic neuroendocrine neoplasms, as there was a statistically significant difference in overall survival across the different stages when stratified by the European Neuroendocrine Tumour Society, while the use of the American Joint Committee for Cancer was limited to distinguishing between patients in stages I and II versus stages III and IV only. Conclusion. All 6 prognostication systems were useful in the prognostication of pancreatic neuroendocrine neoplasm. The World Health Organization 2010 grading system was the best prognostication system in predicting both overall survival in our entire cohort of patients and recurrence‐free survival in the subset of patients who underwent curative resection.

Initial experience with robotic hepatectomy in Singapore: analysis of 48 resections in 43 consecutive patients: Initial experience with robotic hepatectomy in Singapore

Presently, the adoption of laparoscopic hepatectomy is rapidly increasingly worldwide. However, the application of robotic hepatectomy (RH) remains limited and its role remains undefined today.

Perioperative Outcomes of Laparoscopic Repeat Liver Resection for Recurrent HCC: Comparison with Open Repeat Liver Resection for Recurrent HCC and Laparoscopic Resection for Primary HCC

BackgroundThis study aims to determine the safety and efficacy of laparoscopic repeat liver resection (LRLR) for recurrent hepatocellular carcinoma (rHCC).MethodsTwenty patients underwent LRLR for rHCC between 2015 and 2017. The control groups consisted of 79 open RLR (ORLR) for rHCC and 185 LLR for primary HCC. We undertook propensity score-adjusted analyses (PSA) and 1:1 propensity score matching (PSM) for the comparison of LRLR versus ORLR. Comparison of LRLR versus LLR was done using multivariable regression models with adjustment for clinically relevant covariates.ResultsTwenty patients underwent LRLR with three open conversions (15%). Both PSA and 1:1-PSM demonstrated that LRLR was significantly associated with a shorter stay, superior disease-free survival (DFS) but longer operation time compared to ORLR. Comparison between LRLR versus LLR demonstrated that patients undergoing LRLR were significantly older, had smaller tumors, longer operation time and decreased frequency of Pringle’s maneuver applied. There was no difference in other key perioperative outcomes.ConclusionThe results of this study demonstrate that in highly selected patients; LRLR for rHCC is feasible and safe. LRLR was associated with a shorter hospitalization but longer operation time compared to ORLR. Moreover, other than a longer operation time, LRLR was associated with similar perioperative outcomes compared to LLR for primary HCC.