Wai Lun Law

The University of Hong Kong | HKU · Department of Surgery

Breast cancer (BC) is the most common cancer among women in Hong Kong. The Food and Health Bureau commissioned The University of Hong Kong (HKU) to conduct the Hong Kong Breast Cancer Study (HKBCS) with the aim of identifying relevant risk factors for BC in Hong Kong and developing a locally validated BC risk assessment tool for Hong Kong Chinese w...

Exenteration is an ultra‐major surgery that involves radical en‐bloc resection of all pelvic organs including the rectum, sigmoid colon, distal ureter, urinary bladder, internal reproductive organs, regional lymph nodes, and pelvic peritoneum. This chapter reviews the most up‐to‐date available evidence for adjuvant therapy following pelvic exentera...

Background The transection of rectum and fashioning of anastomosis is a crucial step in laparoscopic total mesorectal excision (TME) and the double-stapling technique (DST) is often employed. This study aimed to evaluate the factors that were associated with difficult DST. Method Cases of laparoscopic TME were retrospectively reviewed. The clinico...

Introduction The difference in outcome between right (RCD) and left colonic diverticulitis (LCD) is not well established. The aim of this study was to analyse the presentation and surgical outcome of RCD versus left-sided disease following emergency surgery. Method We conducted a retrospective review of patients presenting with acute diverticuliti...

Background Colonic perfusion is crucial for anastomotic healing and this could be evaluated intraoperatively using indocyanine-green fluorescence imaging (ICG FI). The aim of this study was to ascertain whether the use of ICG FI resulted in the reduction of anastomotic complications, i.e. AL and anastomotic stricture.Methods Consecutive patients wh...

Objective Sporadic early-onset colorectal cancer (EOCRC) has bad prognosis, yet is poorly represented by cell line models. We examine the key mutational and transcriptomic alterations in an organoid biobank enriched in EOCRCs. Design We established paired cancer (n=32) and normal organoids (n=18) from 20 patients enriched in microsatellite-stable...

Background: Advances in sphincter saving procedures improved the quality of life of patients with rectal cancer. However, many of them suffered from functional disturbance after surgery, including the low anterior resection syndrome. Objective: The aim of this study was to evaluate the severity of low anterior resection syndrome after transanal...

Background: According to the American Joint Committee on Cancer staging for cancer of the colon, a minimum of 12 lymph nodes (LN) has to be sampled for accurate staging. This has bearing on the long-term prognosis and the need for adjuvant chemotherapy. The aim of this study was to revisit the association of lymph node yield and the long-term surv...

Background: There is a foreseeable trend that life expectancy is on the rise in many parts of the world. More and more patients will present with colorectal cancer at extreme old age and advanced age is a well-known risk factor for adverse outcomes after surgery. The aim of this study is to evaluate the outcomes of colorectal cancer surgery in pat...

Objective: To explore influences on post-diagnosis dietary decision-making in colorectal cancer survivors (CRC) for future intervention development. Methods: Individual semi-structured interviews were conducted with 30 CRC survivors. All interviews were recorded and transcribed verbatim for grounded theory analysis. Results: Most CRC survivors...

With the increasing incidence and mortality of colorectal cancer (CRC), early and accurate diagnosis is of paramount priority to combat this cancer. Epigenetic alterations such as DNA methylation are innovative biomarkers for CRC, due to their stability, frequency, and accessibility in bodily fluids. In this study, blood samples were prospectively...

Objective: Palliative pelvic exenteration (PPE) is a technically complex operation with high morbidity and mortality rates, considered in patients with limited life expectancy. There is little evidence to guide practice. We performed a systematic review to evaluate the impact of PPE on symptom relief and quality of life (QoL). Methods: A systema...

Background: Robotic surgery and transanal minimally invasive surgery are the two recently developed techniques, which can overcome the difficult pelvic dissection in conventional laparoscopy. This study aimed to compare the early cases of robotic and transanal total mesorectal excision (taTME) using propensity score matching. Methods: The first...

Background. With increasing experience and technological advancement in surgical instruments, surgeons have explored the feasibility of single-incision laparoscopic surgery and natural orifice transluminal endoscopic surgery (NOTES). These techniques aim to further reduce surgical trauma, but are not popular due to their inherent pitfalls including...

Background Despite studies showing superior results in terms of reduced stoma rate and higher primary anastomosis rate, the safety of bridge to surgery stenting (BTS stent) for left-sided malignant colonic obstruction, especially in oncological terms, remains a concern. Aim The aim of this meta-analysis was to evaluate whether BTS stent is a safe...

Background/aims: We determined the rates of metachronous colorectal neoplasm in colorectal cancer (CRC) patients after resection for right (R)-sided or left (L)-sided cancer. Methods: Consecutive CRC patients who had undergone surgical resection for curative intent in our hospital between 2001 and 2004 were identified. R-sided colonic cancers re...

Colorectal cancer is the commonest cancer in Hong Kong. The Cancer Expert Working Group on Cancer Prevention and Screening was established in 2002 under the Cancer Coordinating Committee to review local and international scientific evidence, assess and formulate local recommendations on cancer prevention and screening. At present, the Cancer Expert...

Background: Perfusion plays an important role in anastomotic healing. Indocyanine-green fluorescence angiogram allows objective bowel perfusion assessment. This study aimed to investigate the impact of perfusion assessment on intraoperative decision during left-sided colorectal resections. Method: This was a prospective, single-centre, observati...

Background: Over the past few decades, studies have focused on the safety of stapled anastomosis, especially when compared to that of the handsewn technique. However, studies on the improvement of stapling technology are limited. This study aimed to investigate whether linear triple-row staples (tri-staples) had any advantage over double-row stapl...

Background: It is essential to understand the mechanisms responsible for hepatocellular carcinoma (HCC) progression and chemoresistance in order to identify prognostic biomarkers as well as potential therapeutic avenues. Recent findings have shown that SLIT3 appears to function as a novel tumor suppressor gene in various types of cancers, yet its...

In Hong Kong, breast cancer is the most common cancer among women and poses a significant health care burden. The Cancer Expert Working Group on Cancer Prevention and Screening (CEWG) was set up in 2002 by the Cancer Coordinating Committee to review and assess local and international scientific evidence, and to formulate recommendations for cancer...

Colorectal cancer is a common malignancy globally, and management of rectal cancer is particularly challenging. Not only should the treatment achieve good local disease control and favorable survival; but the body functions should also be preserved. Since the introduction of abdominoperineal resection by Sir Ernest Miles for rectal cancer resection...

Access into peritoneal cavity

Backgrounds and aims The association of melanosis coli with the development of colorectal polyps remains uncertain. Methods From a total of 18263 patients who had received colonoscopy in our hospital, 219 with melanosis coli cases and 438 controls matched by age and sex (at 1:2 ratio) were included in this study. The association of incidence, numb...

Data of melanosis coli and control. (XLSX)

IntroductionAppendectomy has long been the mainstay of intervention for acute appendicitis, aiming at preventing perforation, peritonitis, abscess formation and recurrence. With better understanding of the disease process, non-operative management (NOM) with antibiotics alone has been proved a feasible treatment for uncomplicated appendicitis. This...

Backgrounds and aims: The association of melanosis coli with the development of colorectal polyps remains uncertain. Methods: From a total of 18263 patients who had received colonoscopy in our hospital, 219 with melanosis coli cases and 438 controls matched by age and sex (at 1:2 ratio) were included in this study. The association of incidence, num...

Aim: The prevalence of obturator hernia increases with the ageing population. This study aims to review the surgical outcome of emergency repair for patients with obstructing obturator hernia. Methods: All cases presented with obturator hernia since 1998 were included. Patients’ characteristics, operative findings, and postoperative outcomes were...

OBJECTIVE: The aim of the study was to analyze data from an international collaboration, and ascertain prognostic indicators that inform clinical decision-making and practices regarding the role of pelvic exenteration for locally advanced primary rectal cancer (LARC). BACKGROUND: With improved national screening programs fewer patients present with...

Background The aim of the present study was to evaluate the surgical technique, short-term oncological and perioperative outcomes for the transabdominal division of the levator ani muscles during abdominoperineal excision of the rectum (APER). Methods A systematic review was performed to identify studies reporting on transabdominal division of the...

Inguinal omental fibromatosis is a rare disease entity that could mimic incarcerated inguinal hernia clinically. In the present study, we review the incidence of inguinal omental fibromatosis at our centre. From 1 January1996 to 30 June 2016, all hernia operations performed in all the affiliated hospitals of the University of Hong Kong were reviewe...

Purpose: Laparoscopic rectal resection with total mesorectal excision is a technically challenging procedure, and there are limitations in conventional laparoscopy. A surgical robotic system may help to overcome some of the limitations. This study aimed to compare the short-term operative as well as oncologic outcomes of laparoscopic and robotic r...

Background: Advances in surgical techniques and paradigm changes in rectal cancer treatment have led to a drastic decline in the abdominoperineal resection rate, and sphincter-preserving operation is possible in distal rectal cancer. Objective: The aim of this study is to evaluate the long-term incidence of permanent stoma after sphincter-preser...

Colorectal cancer results from genetic aberrations which accumulate over a long period of time, with malignant and metastatic properties acquired at a relatively late stage. A subpopulation of CD26+ colorectal cancer stem cells are known to be implicated in metastasis. We quantified CD26+ cancer cells in 11 primary tumor samples by flow cytometry,...

Aberrant levels of circulating microRNAs are potential biomarkers for the early detection of colorectal cancer. The aim of this study was to study miR-139-3p and miR-622 in serum as a non-invasive biomarker for colorectal cancer diagnosis. We applied quantitative polymerase chain reaction to determine the levels of miR-139-3p and miR-622 in 42 pair...

Colorectal cancer is the third most common cancer in the world and liver is the most frequent site of distant metastasis with poor prognosis. The aim of this study is to investigate microRNAs leading to liver metastasis. We applied microarray analysis and quantitative PCR to identify and validate dysregulated miRNAs in liver metastases when compare...

Objectives The use of absorbable polylactic acid hook self-gripping polypropylene mesh in open inguinal hernia may potentially reduce operative time and enhance patient recovery. The objective of this randomized trial is to compare the outcomes following self-gripping mesh repair to polypropylene mesh secured with sutures in open inguinal herniopla...

Background: Chewing gum may enhance intestinal motility after surgery. This trial studied whether chewing gum could lead to a further reduction in ileus in patients who had a laparoscopic colorectal resection and followed an enhanced recovery programme. Methods: Patients undergoing laparoscopic colorectal resection were randomized to a control o...

Background: The benefit of mechanical bowel preparation (MBP) in patients undergoing laparoscopic colorectal resections remains a question. This study aimed to evaluate the effect of omitting MBP on patients undergoing laparoscopic bowel resections. Methods: The outcomes of patients who underwent elective colorectal resections for cancer of colon a...

Objective: Serrated polyps (hyperplastic polyps, sessile or traditional serrated adenomas), which can arise in a sporadic or polyposis setting, predispose to colorectal cancer (CRC), especially those with microsatellite instability (MSI) due to MLH1 promoter methylation (MLH1(me+)). We investigate genetic alterations in the serrated polyposis path...

Controversy remains regarding whether preoperative chemoradiation protocol should be applied uniformly to all rectal cancer patients regardless of tumor height. This pooled analysis was designed to evaluate whether preoperative chemoradiation can be safely omitted in higher rectal cancer. An international consortium of 7 institutions was establishe...

Background and Objectives: There has been great enthusiasm for the technique of transanal total mesorectal excision. Coupled with this procedure, we performed single-incision laparoscopic surgery for left colon mobilization. This is a description of our initial experience with the combined approach. Methods: Patients with distal or mid rectal canc...

Objective This study aimed to compare the characteristics of the tumors, the management strategy, and oncologic outcomes of patients with rectal cancer surgery in these two periods: period 1 (1993–2001) and period 2 (2002–2011). Methods All patients who underwent radical resection of rectal cancer from 1993 to 2011 were included. Comparisons of the...

Background: Rectal carcinoids are an uncommon entity comprising only 1%-2% of all rectal tumors. Rectal carcinoids are frequently diagnosed during colonoscopy, but management after polypectomy is still controversial. The aims of this study were to review the surgical procedures for rectal carcinoids and to compare the outcomes of patients after di...

Key Messages 1. Compared with the Hong Kong general population norm, Chinese patients with colorectal neoplasm (CRN) reported worse physical health-related quality of life (HRQOL) but better mental HRQOL and comparable health preference scores. 2. The CRN stage at diagnosis was the most significant determinant of HRQOL. Colorectal cancer was assoc...

Background: With the increasing availability of the surgical robotic system, the young generation colorectal surgeons may learn robotic-assisted rectal surgery upfront. There are currently very limited studies evaluating the learning curve of novice rectal surgeons. Objective: This study aimed to evaluate the learning curve of a surgeon who had...

Transarterial chemoembolization (TACE) is commonly used for the treatment of locally advanced hepatocellular carcinoma (HCC) by its dual effects of chemotherapy and ischemic hypoxia. However, one of the side effects of TACE is the introduction of hypoxic condition, which in turn activates hypoxia-induced survival pathways and enhances VEGF-induced...

Our aim is to determine supportive care needs trajectories over the first year following colorectal cancer (CRC) surgery and identify factors differentiating these trajectories in a sample of Hong Kong Chinese CRC patients. Overall, 247/274 Chinese patients diagnosed with CRC were recruited and assessed following admission for colorectal surgery, t...

Rectal cancer surgery has undergone a rapid evolution in the last few decades. Adoption of total mesorectal excision (TME) dramatically reduced the local recurrence rate and improved the survival rate. TME became the standard procedure for cancer of the middle and lower rectum soon after its introduction. The use of laparoscopic approach in resecti...

Low anterior resection is commonly performed for carcinoma of the distal rectum. Diverting ileostomy has been used to decrease the septic consequence of anastomotic leakage and to reduce the re-operation rate. Nevertheless, subsequent closure of ileostomy can be associated with considerable morbidities. This study aimed to evaluate the morbidities...

Background: In colorectal carcinoma (CRC), activation of the Raf/MEK/ERK signaling pathway is commonly observed. In addition, the commonly used 5FU-based chemotherapy in patients with metastatic CRC was found to enrich a subpopulation of CD26(+) cancer stem cells (CSCs). As activation of the Raf/MEK/ERK signaling pathway was also found in the CD26...

The incidence of colorectal cancer (CRC) is rising rapidly in Chinese. We studied the anatomic distributions and characteristics of CRC in Hong Kong (HK) and Chongqing (CQ) with different CRC epidemiology. It was a retrospective study conducted in three large regional hospitals of the two cities. We identified all patients newly diagnosed with CRC...

Colorectal cancer (CRC) is one of the most common and fatal malignancies worldwide. The poor prognosis of colorectal cancer patients is due to development of chemoresistance and cancer metastasis. Recently osteopontin (OPN) has been associated with stem-like properties in colorectal cancer. This study further examined the clinicopathological signif...

Colorectal cancer (CRC) is one of the most common and fatal malignancies worldwide. The poor prognosis of colorectal cancer patients is due to development of chemoresistance and cancer metastasis. Recently osteopontin (OPN) has been associated with stem-like properties in colorectal cancer. This study further examined the clinicopathological signif...

Background: The overall prognosis of colorectal cancer (CRC) patients is unsatisfactory due to cancer metastasis after operation. This study aims to investigate the clinical significance of plasma osteopontin (OPN) levels as minimally invasive, predictive, and surrogate biomarkers for prognosis of CRC patients. Methods: This randomized study des...