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E C Lai

Publications and source records attributed to E C Lai.

At least 37 records · Page 2Linked to original sources
PubMed2000

The enhancer of split complex of Drosophila includes four Notch-regulated members of the bearded gene family.

During Drosophila development, transcriptional activation of genes of the Enhancer of split Complex (E(spl)-C) is a major response to cell-cell signaling via the Notch (N) receptor. Although the structure and function of the E(spl)-C have been studied intensively during the past decade, these efforts have focused heavily on seven transcription units that encode basic helix-loop-helix (bHLH) repressors; the non-bHLH members of the complex have received comparatively little attention. In this report, we analyze the structure, regulation and activity of the m1, m2 and m6 genes of the E(spl)-C. We find that E(spl)m2 and E(spl)m6 encode divergent members of the Bearded (Brd) family of proteins, bringing to four (m(alpha), m2, m4 and m6) the number of Brd family genes in the E(spl)-C. We demonstrate that the expression of both m2 and m6 is responsive to N receptor activity and that both genes are apparently direct targets of regulation by the N-activated transcription factor Suppressor of Hairless. Consistent with this, both are expressed specifically in multiple settings where N signaling takes place. Particularly noteworthy is our finding that m6 transcripts accumulate both in adult muscle founder cells in the embryo and in a subset of adepithelial (muscle precursor) cells associated with the wing imaginal disc. We show that overexpression of either m2 or m6 interferes with N-dependent cell fate decisions in adult PNS development. Surprisingly, while misexpression of m6 impairs lateral inhibition, overexpression of m2 potentiates it, suggesting functional diversification within the Brd protein family. Finally, we present our initial studies of the structure, expression and regulation of the newest member of the Brd gene family, Ocho, which is located in the recently identified Bearded Complex.

Amino Acid Sequence↗
PubMed2000

Antagonism of notch signaling activity by members of a novel protein family encoded by the bearded and enhancer of split gene complexes.

Cell-cell signaling through the Notch receptor is a principal mechanism underlying cell fate specification in a variety of developmental processes in metazoans, such as neurogenesis. In this report we describe our investigation of seven members of a novel gene family in Drosophila with important connections to Notch signaling. These genes all encode small proteins containing predicted basic amphipathic (&agr;)-helical domains in their amino-terminal regions, as described originally for Bearded; accordingly, we refer to them as Bearded family genes. Five members of the Bearded family are located in a newly discovered gene complex, the Bearded Complex; two others reside in the previously identified Enhancer of split Complex. All members of this family contain, in their proximal upstream regions, at least one high-affinity binding site for the Notch-activated transcription factor Suppressor of Hairless, suggesting that all are directly regulated by the Notch pathway. Consistent with this, we show that Bearded family genes are expressed in a variety of territories in imaginal tissue that correspond to sites of active Notch signaling. We demonstrate that overexpression of any family member antagonizes the activity of the Notch pathway in multiple cell fate decisions during adult sensory organ development. These results suggest that Bearded family genes encode a novel class of effectors or modulators of Notch signaling.

3' Untranslated Regions↗
PubMed1999

Discrete enhancer elements mediate selective responsiveness of enhancer of split complex genes to common transcriptional activators.

In Drosophila, genes of the Enhancer of split Complex [E(spl)-C] are important components of the Notch (N) cell-cell signaling pathway, which is utilized in imaginal discs to effect a series of cell fate decisions during adult peripheral nervous system development. Seven genes in the complex encode basic helix-loop-helix (bHLH) transcriptional repressors, while 4 others encode members of the Bearded family of small proteins. A striking diversity is observed in the imaginal disc expression patterns of the various E(spl)-C genes, suggestive of a diversity of function, but the mechanistic basis of this variety has not been elucidated. Here we present strong evidence from promoter-reporter transgene experiments that regulation at the transcriptional level is primarily responsible. Certain E(spl)-C genes were known previously to be direct targets of transcriptional activation both by the N-signal-dependent activator Suppressor of Hairless [Su(H)] and by the proneural bHLH proteins achaete and scute. Our extensive sequence analysis of the promoter-proximal upstream regions of 12 transcription units in the E(spl)-C reveals that such dual transcriptional activation is likely to be the rule for at least 10 of the 12 genes. We next show that the very different wing imaginal disc expression patterns of E(spl)m4 and E(spl)mgamma are a property of small (200-300 bp), evolutionarily conserved transcriptional enhancer elements, which can confer these distinct patterns on a heterologous promoter despite their considerable structural similarity [each having three Su(H) and two proneural protein binding sites]. We also demonstrate that the characteristic inactivity of the E(spl)mgamma enhancer in the notum and margin territories of the wing disc can be overcome by elevated activity of the N receptor. We conclude that the distinctive expression patterns of E(spl)-C genes in imaginal tissues depend to a significant degree on the capacity of their transcriptional cis-regulatory apparatus to respond selectively to direct proneural- and Su(H)-mediated activation, often in only a subset of the territories and cells in which these modes of regulation are operative.

Animals↗
PubMed1999

Phylogenetic characterization of novel transport protein families revealed by genome analyses.

As a result of recent genome sequencing projects as well as detailed biochemical, molecular genetic and physiological experimentation on representative transport proteins, we have come to realize that all organisms possess an extensive but limited array of transport protein types that allow the uptake of nutrients and excretion of toxic substances. These proteins fall into phylogenetic families that presumably reflect their evolutionary histories. Some of these families are restricted to a single phylogenetic group of organisms and may have arisen recently in evolutionary time while others are found ubiquitously and may be ancient. In this study we conduct systematic phylogenetic analyses of 26 families of transport systems that either had not been characterized previously or were in need of updating. Among the families analyzed are some that are bacterial-specific, others that are eukaryotic-specific, and others that are ubiquitous. They can function by either a channel-type or a carrier-type mechanism, and in the latter case, they are frequently energized by coupling solute transport to the flux of an ion down its electrochemical gradient. We tabulate the currently sequenced members of the 26 families analyzed, describe the properties of these families, and present partial multiple alignments, signature sequences and phylogenetic trees for them all.

Amino Acid Sequence↗
PubMed1999

Movement and reaction times and fine coordination tasks following pallidotomy.

The effect of a unilateral, microelectrode-guided lesion in the globus pallidum internum (GPi) was evaluated in 41 patients (21 women) with moderately advanced Parkinson's disease (PD). The mean age was 60.3+/-9.0 years (range, 40-74) and the mean symptom duration was 14.7+/-5.3 years (range, 4-25). In addition to clinical ratings, movement time (MT) and reaction time (RT) tests were performed at baseline and 3 months after surgery during the "practically defined off" state (more than 12 hours after the last dose of levodopa). Improvement occurred bilaterally with more robust and statistically significant improvement on the contralateral side in all RT tests. Simple reaction time (SRT) improved by 14.5% (p<0.001) and the choice reaction time (CRT) by 12.2% (p<0.001) when the arm contralateral to the pallidotomy side was tested. There was a trend toward improvement in the ipsilateral arm. The MT, determined by repetitive movement between two adjacent targets, improved by 24% contralaterally (p<0.0001) and by 12% ipsilaterally (p<0.005). In addition, the Purdue Pegboard (PP) test scores, used to evaluate hand dexterity, improved on the contralateral side by 35.5% (p<0.0002) but there was no statistically significant ipsilateral improvement. To the extent that MT and RT are quantitative measures of bradykinesia, our study provides evidence that this parkinsonian feature improves after pallidotomy.

Adult↗
PubMed1999

Therapeutic developments in amyotrophic lateral sclerosis.

There is currently no effective treatment for amyotrophic lateral sclerosis (ALS), a devastating disorder of the human nervous system that, due to motoneurone degeneration, causes progressive loss of muscle function and death. The relentless progression of ALS and the uniformly poor prognosis have been unhindered by a variety of therapeutic agents tested in previous clinical studies. Recently, two drugs, namely riluzole and recombinant human insulin-like growth factor-I (IGF-1), have been reported to benefit patients with ALS by improving survival or slowing disease progression. Several other drugs, such as gabapentin and various neurotrophic factors, are being investigated in on-going clinical trials. Therapeutic developments in ALS have been hampered by the fact that the precise cause of the disease remains unknown. In addition, there are considerable variations in disease related characteristics among patients, rendering accurate measurements of disease progression difficult. Advances in theories of pathogenesis, such as genetic factors, glutamate excitotoxicity, oxidative stress, autoimmune mechanism and cytoskeletal abnormality will help guide the development of future therapies. Newer approaches to therapy may include suitable glutamate antagonists, small molecules that augment neurotrophic factor function, and anti-oxidants. Combination therapy of effective agents should be considered.

Journal Article↗
PubMed1998

Selegiline is ineffective in a collaborative double-blind, placebo-controlled trial for treatment of amyotrophic lateral sclerosis.

BACKGROUND: The cause of amyotrophic lateral sclerosis (ALS) is not known, and there is no effective treatment. Cell death may be caused by oxidative damage. Selegiline hydrochloride (Eldepryl) is a monoamine oxidase-B inhibitor with antioxidant properties. OBJECTIVE: To determine if selegiline affects the clinical course of patients with ALS. DESIGN: Six-month, double-blind, placebo-controlled study of 133 patients with classical ALS and symptoms for less than 3 years. The primary end point to indicate effectiveness was the rate of change of the Appel ALS total score, an index of disease severity that incorporates strength and function in limbs, respiratory function, and bulbar function. RESULTS: Of the 133 patients, 67 were randomized to receive selegiline and 66 to receive placebo. One hundred four patients (53 in the selegiline group and 51 in the placebo group) completed the 6-month trial. Both groups were comparable for baseline characteristics and mean Appel ALS total score (70.5 points for the selegiline group and 70.6 for the placebo group). There was no difference in the rate of progression as measured by the Appel ALS total score, showing an average increase of 22 points in 6 months. The monthly rate of change was 3.4 for the selegiline group and 3.5 for the placebo group. There was 1 adverse reaction: worsening depression. Seven patients died during the study (4 in the selegiline group and 3 in the placebo group). CONCLUSION: Selegiline treatment had no significant effect on the rate of clinical progression or outcome of ALS.

Administration, Oral↗
PubMed1998

Accuracy of the clinical diagnoses of Lewy body disease, Parkinson disease, and dementia with Lewy bodies: a clinicopathologic study.

BACKGROUND: Whether Parkinson disease (PD) and dementia with Lewy bodies (DLB) represent 2 distinct nosologic entities or are diverse phenotypes of Lewy body disease is subject to debate. OBJECTIVES: To determine the accuracy of the diagnoses of Lewy body disease, PD, and DLB by validating the clinical diagnoses of 6 neurologists with the neuropathologic findings and to identify early predictors of the diagnoses. METHODS: Six raters who were unaware of the neuropathologic diagnoses analyzed 105 clinical vignettes corresponding to 29 cases of Lewy body disease (post hoc analysis of 15 patients with PD and 14 with DLB) and 76 patients without PD or DLB whose cases were confirmed through autopsy findings. MAIN OUTCOME MEASURES: Sensitivity and positive predictive value (PPV) were chosen as validity measures and the K statistic as a reliability measure. RESULTS: Interrater reliability for the diagnoses of Lewy body disease and PD was moderate for the first visit and substantial for the last, whereas agreement for diagnosis of DLB was fair for the first visit and slight for the last. Median sensitivity for diagnosis of Lewy body disease was 56.9% for the first visit and 67.2% for the last; median PPV was 60.0% and 77.4%, respectively. Median sensitivity for the diagnosis of PD was 73.3% for the first visit and 80.0% for the last; median PPV was 45.9% and 64.1%, respectively. Median sensitivity for the diagnosis of DLB was 17.8% for the first visit and 28.6% for the last; median PPV was 75.0% for the first visit and 55.8% for the last. The raters' results were similar to those of the primary neurologists. Several features differentiated PD from DLB, predicted each disorder, and could be used as clinical pointers. CONCLUSIONS: The low PPV with relatively high sensitivity for the diagnosis of PD suggests overdiagnosis. Conversely, the extremely low sensitivity for the diagnosis of DLB suggests underdiagnosis. Although the case mix included in the study may not reflect the frequency of these disorders in practice, limiting the clinical applicability of the validity measures, the raters' results were similar to those of the primary neurologists who were not exposed to such limitations. Overall, our study confirms features suggested to predict these disorders, except for the early presence of postural imbalance, which is not indicative of either disorder.

Adult↗
PubMed1998

Biliary complications after hepatic resection: risk factors, management, and outcome.

OBJECTIVE: To identify the risk factors for the development of biliary complications after hepatic resection and to evaluate management in relation to the outcomes of these patients. DESIGN: Biliary complications are a common cause of major morbidity after hepatic resection. A survey was made of all patients undergoing hepatic resection at 1 institution. Perioperative risk factors related to the development of biliary complications were identified using multivariate analysis. Management and outcome were analyzed also. SETTING: A tertiary referral center. PATIENTS: From January 1, 1989, to October 31, 1995, 347 consecutive patients underwent 229 major and 118 minor hepatic resections. MAIN OUTCOME MEASURE: Development of postoperative biliary complications. RESULTS: Biliary complications developed in 28 (8.1%) of 347 patients; these complications carried high risks for liver failure (35.7%) and operative mortality (39.3%). Stepwise logistic regression analysis identified increasing age, higher preoperative white blood cell count, left-sided hepatectomy, and prolonged operation time as the independent predictors of development of biliary complications. Conservative treatment or nonoperative measures alone, such as percutaneous drainage or endoscopic therapy, were effective in treating the complication in 13 of 19 patients, but those who required reoperation had a high mortality rate (7 [77.8%] of 9 patients). Patients with demonstrable leakage from the common bile duct or its bifurcation tended to have poor outcomes. CONCLUSIONS: Biliary complications are a common and serious cause of morbidity after hepatic resection. Preresection cholangiography for finding biliary tract anomaly is recommended before left-sided hepatectomy. Although nonoperative measures are the preferred approach for selected patients with biliary complications, those with demonstrable leakage from the common bile duct or its bifurcation have a grave prognosis and may benefit from early surgical intervention.

Adult↗
PubMed1998

Postoperative adjuvant chemotherapy after curative resection of hepatocellular carcinoma: a randomized controlled trial.

OBJECTIVE: To study the effect of adjuvant chemotherapy after curative hepatic resection in patients with hepatocellular carcinoma. DESIGN: A randomized controlled trial. SETTING: A tertiary referral center. PATIENTS: During a 54-month period, 142 patients with hepatocellular carcinoma underwent hepatic resection at 1 institution. Sixty-six patients who survived the operation and had no demonstrable evidence of residual disease on ultrasonographic examination and hepatic angiographic testing at 1 month after surgery agreed to participate in the study. The median follow-up time was 28.3 months. INTERVENTION: Thirty patients received a combination of intravenous epirubicin hydrochloride (8 doses of 40 mg/m2 each at 6-week intervals) and transarterial chemotherapy using an emulsion of iodized oil and cisplatin (3 courses with a maximum dose of 20 mL each at 2-month intervals). Thirty-six patients had no adjuvant treatment. MAIN OUTCOME MEASURES: Recurrence rate and disease-free survival. RESULTS: A total of 138 courses of intravenous epirubicin was given to the 30 patients. Sixty-one courses of transarterial chemotherapy were given to only 29 of the 30 patients assigned to the treatment group, because the hepatic artery in 1 patient was thrombosed. Six patients (20%) had chemotherapy-related complications with no mortality. Twenty-three of 30 patients in the treatment group and 17 of 36 patients in the control group had recurrences (P=.01). Patients who received adjuvant chemotherapy had a higher incidence of extrahepatic metastases (11 patients vs 5 patients; P=.03). The respective disease-free survival rates at 1, 2, and 3 years were 50%,36%, and 18% for the treatment group and 69%, 53%, and 48% for the control group (P=.04). CONCLUSION: In a group of patients who underwent curative resection of hepatocellular carcinoma, postoperative adjuvant chemotherapy using the present regimen was associated with more frequent extrahepatic recurrences and a worse outcome.

Antineoplastic Agents↗
PubMed1998

Endoscopic retrograde cholangiopancreatography and endoscopic endoprosthesis insertion in patients with Klatskin tumors.

OBJECTIVE: To assess the value and the associated morbidity of endoscopic retrograde cholangiopancreatography (ERCP) and endoscopic endoprosthesis insertion in the treatment of patients with Klatskin tumors. DESIGN: Retrospective study. SETTING: A tertiary referral center. PATIENTS: Fifty-five consecutive patients with Klatskin tumors diagnosed through typical cholangiographic and computed tomographic findings. INTERVENTION: Standard ERCP with endoscopic stenting technique was employed. Once the diagnosis of Klatskin tumor was confirmed on cholangiogram, endoscopic stenting was performed to bypass the stricture. Multiple stents were inserted if necessary to ensure adequate biliary drainage. MAIN OUTCOME MEASURES: The success rate of ERCP and endoscopic endoprosthesis insertion, successful drainage rate, early complications of endoscopic procedure, procedure-related mortality, and long-term outcome of endoprosthesis. RESULTS: Of the 55 patients, cholangiography was performed in 53 (96%). In the 49 patients in whom endoscopic stenting was attempted, the procedure was successful in 28 patients (57%) at the first attempt and 8 patients (16%) at the second attempt, resulting in a cumulative success rate of 73%. Only 20 of these patients had satisfactory biliary drainage, resulting in an overall successful drainage rate of 41%. Early complications, including acute cholangitis, acute pancreatitis, and postpapillotomy bleeding occurred in 14 patients (25%). Three patients (5%) died of procedure-related complications. The median patency of the first endoprosthesis inserted was 1 week (range, 0-8 wk). The 30-day mortality rate was 18%. CONCLUSIONS: In patients with Klatskin tumors, ERCP and endoscopic endoprosthesis insertion have a low successful drainage rate, are associated with high morbidity and procedure-related mortality, and have a limited effect on long-term palliation. Endoscopic retrograde cholangiopancreatography and endoscopic endoprosthesis insertion have a limited value in the management of patients with Klatskin tumors.

Adult↗
PubMed1998

Retrospective application of a set of clinical diagnostic criteria for the diagnosis of multiple system atrophy.

We estimated the accuracy of a modified commonly used set of clinical diagnostic criteria for the diagnosis of multiple system atrophy (MSA) by retrospectively applying the criteria to the features recorded by six neurologists who had evaluated 105 autopsy-confirmed cases (16 MSA and 89 non-MSA disorders). Cases were abstracted from the records of the patients' first visit to an academic center, and were presented as clinical vignettes to six neurologists, each of whom recorded the main clinical features of the presented clinical vignette on a standardized form. Sensitivity and positive predictive values were chosen as validity outcome measures and were calculated by comparing the applied diagnostic criteria to the neuropathologic information. Of note, most MSA patients in this study (mainly those with Shy-Drager type) had not received levodopa therapy since the primary neurologists often had not perceived a need to administer this treatment. The validity of the retrospectively applied criteria for the diagnosis of possible MSA (sensitivity: median, 53%, range, 50-69%; positive predictive value: 30%, 28-39%) and probable MSA (sensitivity: 44%, 31-60%; positive predictive value: 68%, 54-80%) at the first visit was suboptimal. The best, still not perfect, accuracy for this set of diagnostic criteria was obtained when six out of eight features (sporadic adult onset, dysautonomia, parkinsonism, pyramidal signs, cerebellar signs, no levodopa response, no cognitive dysfunction, or no downward gaze supranuclear palsy) were present (median sensitivity, 59%; range, 50-75%; positive predictive value: 67%, 53-83%). This is the first study to validate criteria for the clinical diagnosis of MSA. Our data suggest that it is difficult to achieve an early and accurate clinical diagnosis of this disorder. The probability of correctly diagnosing MSA increases when at least six features of this modified set of criteria are present or when requiring the set for probable MSA.

Adult↗
PubMed1998

Long-term quantitative results following fundoplication and antroplasty for gastroesophageal reflux and delayed gastric emptying in children.

BACKGROUND: The operative management of children with combined gastroesophageal reflux and delayed gastric emptying is controversial. This study measures the long-term follow-up of gastric emptying in children who have undergone gastroesophageal fundoplication combined with antroplasty. METHODS: Fifteen randomly selected children with gastroesophageal reflux and scintigraphically demonstrated delayed gastric emptying underwent fundoplication and antroplasty. Each patient had another gastric emptying scintigraphic study performed an average of 3.6 years postoperation. RESULTS: All patients reported improvement of their symptoms compared with before the operation, and none required further medical therapy for gastroesophageal reflux or experienced dumping syndrome. Eleven of the 15 patients had significant long-term improvement of their gastric emptying postoperatively. The mean percent of isotope meal remaining in the stomach at 90 minutes improved from 72% preoperatively to 40% postoperatively (P = 0.0005). CONCLUSIONS: Gastric emptying in children with gastroesophageal reflux and delayed gastric emptying is significantly improved for several years in three-fourths of patients after fundoplication and antroplasty. Fundoplication and concomitant antroplasty are recommended for symptomatic children with documented gastroesophageal reflux and delayed gastric emptying.

Adolescent↗
PubMed1998

The outcome of research training during surgical residency.

BACKGROUND/PURPOSE: The exposure to research during residency is currently an integral part of most academic surgical training programs. In this study, graduates of two surgical programs were surveyed to characterize their research experience and to determine the effects on their careers. METHODS: Between 1975 and 1990, 86 and 61 residents completed general surgical training programs at UCLA Medical Center and at Harbor-UCLA Medical Center, respectively. An anonymous survey was sent to each graduate regarding his research experience and current practice. RESULTS: Of the graduates who spent 2 years in research, 47% now hold academic positions, compared with 23% for those who spent less than 2 years (P = .18). When the graduates were segregated according to their desire to enter the laboratory, 49% of graduates who requested research time hold academic positions, whereas only 13% of those who would not request research are in academic positions (P = .01). CONCLUSIONS: Residents who strongly desire a period of research during surgical residency are also more productive in the laboratory. This information should be considered in selecting residents for research training in the current era of academic budget restriction and managed health care.

Attitude of Health Personnel↗
PubMed1998

Prospective randomized study of early versus delayed laparoscopic cholecystectomy for acute cholecystitis.

OBJECTIVE: A prospective randomized study was undertaken to compare early with delayed laparoscopic cholecystectomy for acute cholecystitis. SUMMARY BACKGROUND DATA: Laparoscopic cholecystectomy for acute cholecystitis is associated with high complication and conversion rates. It is not known whether there is a role for initial conservative treatment followed by interval elective operation. METHOD: During a 26-month period, 99 patients with a clinical diagnosis of acute cholecystitis were randomly assigned to early laparoscopic cholecystectomy within 72 hours of admission (early group, n = 49) or delayed interval surgery after initial medical treatment (delayed group, n = 50). Thirteen patients (four in the early group and nine in the delayed group) were excluded because of refusal of operation (n = 6), misdiagnosis (n = 5), contraindication for surgery (n = 1), or loss to follow-up (n = 1). RESULTS: Eight of 41 patients in the delayed group underwent urgent operation at a median of 63 hours (range, 32 to 140 hours) after admission because of spreading peritonitis (n = 3) and persistent fever (n = 5). Although the delayed group required less frequent modifications in operative technique and a shorter operative time, there was a tendency toward a higher conversion rate (23% vs. 11%; p = 0.174) and complication rate (29% vs. 13%; p = 0.07). For 38 patients with symptoms exceeding 72 hours before admission, the conversion rate remained high after delayed surgery (30% vs. 17%; p = 0.454). In addition, delayed laparoscopic cholecystectomy prolonged the total hospital stay (11 days vs. 6 days; p < 0.001) and recuperation period (19 days vs. 12 days; p < 0.001). CONCLUSIONS: Initial conservative treatment followed by delayed interval surgery cannot reduce the morbidity and conversion rate of laparoscopic cholecystectomy for acute cholecystitis. Early operation within 72 hours of admission has both medical and socioeconomic benefits and is the preferred approach for patients managed by surgeons with adequate experience in laparoscopic cholecystectomy.

Acute Disease↗
PubMed1998

Laparoscopy and laparoscopic ultrasonography avoid exploratory laparotomy in patients with hepatocellular carcinoma.

OBJECTIVE: This prospective study evaluates the value of laparoscopy and laparoscopic ultrasonography (USG) in avoiding exploratory laparotomy in patients with hepatocellular carcinoma (HCC). SUMMARY BACKGROUND DATA: Laparotomy and intraoperative USG is the gold standard to determine the resectability of HCC. No palliation can be offered to patients found to have unresectable disease, and the surgical exploration causes morbidity. METHODS: From June 1994 to June 1996, 110 of 370 patients (30%) with HCC were considered candidates for possible hepatic resection. Preoperative liver function was assessed using Child-Pugh grading and indocyanine green retention test. The extent of disease was evaluated with radiologic studies, including percutaneous USG, computerized tomography scan, and hepatic angiogram. Nineteen patients were excluded from the study because of previous upper abdominal surgery (n = 12), ruptured tumors (n = 4), refusal by patients (n = 2), and instrument failure (n = 1). Laparoscopy and laparoscopic USG was performed on 91 patients immediately before a planned laparotomy aiming at hepatic resection. Laparotomy was aborted when definite evidence of unresectable disease was found on laparoscopic examination. RESULTS: The median time required for laparoscopy and laparoscopic USG was 30 minutes (range, 10 to 120 minutes). Fifteen patients had evidence of unresectable disease on laparoscopic examination. Among the remaining 76 patients who underwent laparotomy, 9 had exploration only and 67 underwent hepatic resection. Thus, exploratory laparotomy was avoided in 63% of patients with unresectable disease. The laparoscopic examination failed to confirm unresectable disease more often when the tumor was >10 cm in diameter. The procedure accurately assessed the adequacy of the liver remnant and the presence of intrahepatic metastases, but it was less sensitive in determining the presence of tumor thrombi in major vascular structures and the extent of invasion of adjacent organs. When unresectable disease was detected without the need for a laparotomy, the postoperative recovery was faster, and the nonoperative treatment for the tumor could be initiated earlier. CONCLUSIONS: Laparoscopy with laparoscopic USG avoids unnecessary laparotomy in patients with HCC and should precede a planned laparotomy aiming at hepatic resection.

Adolescent↗