Robotic hepatectomy: initial experience of a single institution in Singapore

<p><b>INTRODUCTION</b>In this study, we report our initial experience with robotic hepatectomy.</p><p><b>METHODS</b>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.</p><p><b>RESULTS</b>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.</p><p><b>CONCLUSION</b>Our initial experience confirmed the feasibility and safety of robotic hepatectomy.</p>

Atypical enhancement pattern of hepatocellular carcinoma with portal vein thrombosis on multiphasic CT

<p><b>INTRODUCTION</b>The 2005 American Association for Study of Liver Diseases (AASLD) diagnostic criteria allow non-invasive diagnosis of hepatocellular carcinoma (HCC) based on their enhancement pattern but we have observed a high incidence of atypical enhancement characteristics in HCC associated with portal vein thrombosis. This study seeks to examine the radiological features of this particular subgroup.</p><p><b>MATERIALS AND METHODS</b>Patients with HCC and portal vein thrombosis who underwent pre-treatment multiphasic CT imaging were drawn from a surgical database. The arterial, portal venous and delayed phase images were assessed qualitatively and quantitatively (with region of interest [ROI] analysis) for lesion hypervascularity and washout. The background enhancement of the left and right lobes of the liver was also quantifi ed by ROI analysis.</p><p><b>RESULTS</b>Twenty-fi ve lesions in 25 patients were selected for analysis. Qualitative analysis showed that 10/25 (40%) lesions demonstrated arterial hypervascularity while 16/25 (64%) lesions showed washout. Ten out of 25 (40%) lesions demonstrated both arterial hypervascularity and washout. Quantitative analysis showed that the average absolute lesion enhancement from precontrast to arterial phases was 49.1 (± 17.1) HU for hypervascular lesions compared to 23.8 (± 16.6) HU for non-hypervascular lesions (P <0.01). The mean absolute enhancement of the background liver parenchyma in the arterial phase was 13.79 (± 7.9) HU for hypervascular lesions compared to 36.6 (± 30.6) HU for non-hypervascular lesions (P = 0.03).</p><p><b>CONCLUSION</b>A large proportion of HCC with portal vein thrombosis lack characteristic arterial hypervascularity, which may be secondary to compensatory increased arterial supply to the background liver. This is a potential pitfall when applying imaging criteria for diagnosis of HCC.</p>

Wash-out of hepatocellular carcinoma: quantitative region of interest analysis on CT

<p><b>INTRODUCTION</b>This study aims to determine if the quantitative method of region-of-interest (ROI) analysis of lesion attenuation on CT may be a useful adjunct to the conventional approach of diagnosis by visual assessment in assessing tracer wash-out in hepatocellular carcinomas.</p><p><b>MATERIALS AND METHODS</b>From a surgical database of 289 patients from 2 institutions, all patients with complete surgical, pathological and preoperative multiphasic CT scans available for review were selected. For each phase of scanning, HU readings of lesion obtained (Lesion(arterial), Lesion(PV) and Lesion(equilibrium)) were analysed using receiver operating curves (ROC) to determine the optimal method and cut-off value for quantitative assessment of tumour wash-out (Lesion(arterial - equilibrium), Lesion(PV - equilibrium) or Lesion(peak - equilibrium)).</p><p><b>RESULTS</b>Ninety-four patients with one lesion each met the inclusion criteria. The area under the curve (AUC) values for Lesion(arterial - equilibrium) (0.941) was higher than the AUC for Lesion(pv - equilibrium) (0.484) and for Lesion(peak - equilibrium) (0.667). Based on ROC analysis, a cut-off of 10HU value for Lesion(arterial - equilibrium) would yield sensitivity and specificity of 91.5% and 80.9%, respectively. ROI analysis detected 9/21 (42.9%) of lesions missed by visual analysis. Combined ROI and visual analysis yields a sensitivity of 82/94 (87.2%) compared to 73/94 (77.7%) for visual analysis alone.</p><p><b>CONCLUSION</b>Using a cut-off of 10 HU attenuation difference between the arterial and equilibrium phases is a simple and objective method that can be included as an adjunct to visual assessment to improve sensitivity for determining lesion wash-out on CT.</p>

Ovarian carcinoma presenting with isolated contralateral inguinal lymph node metastasis: a case report

<p><b>INTRODUCTION</b>Ovarian carcinoma usually presents at an advanced stage with diffuse intraabdominal manifestations. We report a patient who presented with a right groin swelling.</p><p><b>CLINICAL PICTURE</b>The only clinical abnormality was an enlarged right inguinal lymph node (3 x 2 cm), for which excision biopsy revealed metastatic adenocarcinoma. A computed tomography (CT) scan showed an enlarged left ovarian lesion (9.0 x 6.4 cm).</p><p><b>TREATMENT AND OUTCOME</b>Laparotomy with total hysterectomy, bilateral salpingo-oophrectomy and partial omentectomy were performed. Histology confirmed left ovarian adenocarcinoma, consistent with the earlier histology of the right inguinal lymph node. There were no other sites of involvement. Postoperatively, the patient received adjuvant chemotherapy for treatment of FIGO Stage IIIc ovarian carcinoma and is clinically disease free 13 months after surgery.</p><p><b>CONCLUSIONS</b>Ovarian cancer presenting with inguinal lymph node metastases is uncommon. Ovarian cancer which manifests solely as a contralateral inguinal lymph node metastasis has not been previously reported. This case illustrates a rare presentation of ovarian carcinoma, and underscores the need to consider ovarian carcinoma in the differential diagnosis of women with inguinal lymphadenopathy.</p>

Infected pancreatic necrosis--an evaluation of the timing and technique of necrosectomy in a Southeast Asian population

<p><b>INTRODUCTION</b>Acute pancreatitis appears to be less prevalent in multi-ethnic Southeast Asia, where the aetiology also appears to be influenced by ethnicity. As with acute pancreatitis elsewhere, however, pancreatic necrosis is a cause of significant mortality and the aim of this study was to review our institutional experience with pancreatic necrosectomy.</p><p><b>MATERIALS AND METHODS</b>The records of all patients who underwent pancreatic necrosectomy from January 2000 to December 2004 were analysed. Indications for surgery were the presence of infected necrosis, unresolving sepsis attributable to ongoing pancreatitis or the presence of gas in the pancreatic bed on imaging. Surgical debridement was achieved by debridement with closure over drains or by debridement with open packing.</p><p><b>RESULTS</b>The cohort comprised 14 of 373 patients admitted for acute pancreatitis (3.8%), with an overall mortality rate of 29%. All patients had infected necrosis with positive bacteriological cultures. Eight patients (57%) underwent debridement with closure over drains and 6 patients (43%) underwent debridement with open packing. All mortalities occurred in patients who underwent open packing, who were also associated with a higher mean Acute Physiology and Chronic Health Evaluation (APACHE) II score. The mortality rate in patients who underwent debridement less than 4 weeks after admission was 33% (2 of 6), compared with 25% (2 of 8) in patients who underwent debridement after 4 weeks. There were no mortalities in patients operated on after 6 weeks.</p><p><b>CONCLUSION</b>Surgical debridement with closure of drains and a policy of performing delayed necrosectomy are viable in our population.</p>

Image-guided radiofrequency ablation of liver malignancies: experience at Singapore General Hospital

<p><b>UNLABELLED</b>The aim of this paper was to study the efficacy, side effects and complications of radiofrequency (RF) ablation of primary and metastatic liver malignancies.</p><p><b>MATERIALS AND METHODS</b>We retrospectively reviewed 57 patients (39 men, 18 women; mean age, 63 years; age range, 44 to 83 years) who underwent RF ablation for liver malignancies from January 2002 to December 2004. A total of 87 tumours were ablated - 71 (81.6%) hepatocellular carcinomas and 16 (18.4%) metastases (from primaries in the colon, stomach and pancreas). RF ablation was performed either percutaneously (n = 71) under conscious sedation or intraoperatively (n = 16) under general anaesthesia. Follow-up ranged from 1 month to 41 months (mean, 15.2) and included computed tomography (CT) 1 day, 1 month and 3 months after ablation, and half-yearly thereafter. Patients were observed for local tumour progression and for the emergence of new tumours.</p><p><b>RESULTS</b>Four patients with a total of 5 tumours were lost to follow-up. Of the remaining 82 tumours treated, complete ablation was attained in 66 tumours after a single procedure, giving a primary effectiveness rate of 80.5%. Seven (8.5%) required 2 procedures to achieve complete ablation, giving a secondary effectiveness rate of 89% after 2 ablations. One tumour (1.2%) required 3 procedures to achieve complete ablation. One tumour required 4 procedures to date, with the latest follow-up CT still demonstrating incomplete ablation. Two tumours (2.4%) had an initial RF ablation and subsequent transarterial chemoembolisation (TACE). One tumour had an initial RF ablation followed by 32Phosphorus-biosilicon (BrachySil) injection, the latter as part of a Phase IIA trial. One tumour required 2 RF ablations and a subsequent TACE. Lastly, 3 tumours received initial RF ablation but subsequent local tumour progression was not treated as the patients were deemed unfit for repeat ablation. No procedure-related deaths or major complications were encountered. Minor complications were reported in 2 patients (3.8%) - subcapsular haematoma and thermal injury to the adjacent gastric antrum, both not necessitating surgical intervention.</p><p><b>CONCLUSIONS</b>RF ablation is an effective, safe and relatively simple procedure for the treatment of unresectable liver malignancies.</p>