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L T de Wit

Publications and source records attributed to L T de Wit.

At least 55 records · Page 3Linked to original sources
PubMed1997

Value of laparoscopic ultrasonography in staging of proximal bile duct tumors.

The additional value of laparoscopic ultrasonography was evaluated prospectively in 35 patients undergoing diagnostic laparoscopy for a suspected potentially resectable proximal bile duct tumor. Findings were compared with transabdominal ultrasonography, laparoscopy, surgery, and pathology. Laparoscopic ultrasonography was able to visualize the presence and origin of small bile duct tumors or stones and small liver metastases, which could not be seen or could be visualized only doubtfully by ultrasonography and laparoscopy. Laparoscopic ultrasonography was more useful in staging of small tumors of the gallbladder or proximal common bile duct than in staging bifurcation (Klatskin) tumors. Additional information provided by laparoscopic ultrasonography led to a change in diagnosis or tumor stage in eight patients (23%) and to avoidance of laparotomy in three patients (9%).

Adult↗
PubMed1996

Laparoscopic ultrasonography for staging of gastrointestinal malignancy.

BACKGROUND: Diagnostic laparoscopy has been used frequently as a preoperative staging procedure for different gastrointestinal malignancies. The assessment of solid abdominal organs and retroperitoneal ingrowth or detection of lymph-node metastasis is limited, however. A recent development, laparoscopic ultrasonography, will probably increase the preoperative evaluation of these lesions and thus further improve the preoperative staging. METHOD: Since 1993 diagnostic laparoscopy combined with laparoscopic ultrasonography has been performed as an additional diagnostic procedure in patients who have already been selected for curative resection of different GI malignancies. In this prospective study, staging after conventional work-up is compared with the tumour stage after laparoscopy. All patients underwent exploratory laparotomy except those with histologically proven metastases/ingrowth. RESULTS: For patients with cancer of the esophagus and gastric cardia (n = 56) the preoperative stage was altered in 17% but laparotomy could only be avoided in 5% (for a subgroup of patients with a tumour of the gastric cardia laparotomy was avoided in 11%). Additional findings during laparoscopy showed that laparotomy could be avoided in 55% of the patients (n = 44) with primary liver tumours, liver metastasis or proximal bile duct tumours. For patients with pancreatic head tumours (n = 73) the preoperative stage of the tumor changed in 40%; the strategy of treatment was changed in 26% and laparotomy could be avoided in 20%. CONCLUSIONS: Laparoscopy combined with laparoscopic ultrasonography is effective (more accurate) in the staging of gastrointestinal malignancies, in particular for patients with liver, biliary and pancreatic tumours. The preoperative tumour stage changed between 15 and 60% for the different gastrointestinal malignancies and laparotomy could be avoided in 5-55%. The procedure is highly operator-dependent and has a learning curve.

Endosonography↗
PubMed1996

Comparison of laparoscopic and transabdominal ultrasonography in staging of cancer of the pancreatic head region.

The value of laparoscopic ultrasonography in the staging of cancer of the pancreatic head region was compared prospectively to that of transabdominal ultrasonography. Eighty patients underwent LUS, after ultrasonography had shown normal Doppler findings of portal vessels and no signs of metastatic disease. Presence of hepatic or lymph node metastases and vascular tumor infiltration were evaluated in 74 and 48 patients, respectively. Laparoscopic ultrasonography showed liver metastases in 10 patients (14%). Specificity and positive predictive value for the laparoscopic technique determining vascular ingrowth were 97% and 92%, respectively, versus 89% and 77% by sonography in patients with normal Doppler findings (difference not statistically significant). Laparoscopic ultrasonography has shown improved detection of hepatic metastases compared to sonography, but it still must prove its value, as compared to noninvasive methods, in local staging.

Adult↗
PubMed1996

Preoperative biliary drainage, colonisation of bile and postoperative complications in patients with tumours of the pancreatic head: a retrospective analysis of 241 consecutive patients.

OBJECTIVE: To analyse the outcome of preoperative biliary drainage in patients being operated on for a tumour in the pancreatic head. DESIGN: Retrospective study. SETTING: University hospital, The Netherlands. SUBJECTS: Consecutive series of 241 patients. MAIN OUTCOME MEASURES: Decline in bilirubin concentrations and bacterial contamination of bile as a result of preoperative drainage. Incidence of postoperative complications in patients who underwent preoperative drainage and those who did not. RESULTS: 184/241 patients underwent preoperative biliary drainage. Endoscopic drainage was the most effective, shown by a median reduction in bilirubin concentrations of 82%, 74%, and 50% after endoscopic drainage (n = 149), papillotomy (n = 25) and external drainage (n = 10), respectively. Bacterial contamination of bile was significantly more common when an endoprosthesis was used, but did not result in a higher rate of infective complications. 163 Whipple's resections, 33 total pancreatectomies, and 45 biliary-enteric bypasses were performed. 137/241 (57%) patients had postoperative complications. There was no significant difference in the incidence of postoperative complications between patients who had preoperative biliary drainage and those who did not (p = 0.4).

Adult↗
PubMed1995

Prognostic factors for survival after pancreaticoduodenectomy for patients with carcinoma of the pancreatic head region.

BACKGROUND: The aim of this study was to determine prognostic factors for survival after pancreaticoduodenectomy (PD) for carcinoma of the pancreatic head region. METHODS: From 1983 to 1992. 176 patients underwent PD for ampullary carcinoma (n = 67), distal bile duct carcinoma (n = 42), or pancreatic carcinoma (n = 67). The first choice for resection was subtotal PD (n = 146), but patients with a tumor-positive pancreatic margin or a brittle pancreatic duct underwent total PD (n = 30). RESULTS: Hospital mortality was 4.7% after subtotal PD and 20% after total PD. Overall 5-year survival was 31%. Survival after PD for ampullary carcinoma care. (5-year, 50%) was significantly better (P < 0.001) than for distal bile duct carcinoma (24%) and pancreatic carcinoma (14%). Independent negative prognostic factors for survival (multivariate analysis) were involved resection margins (hazard rate ratio [HRR] 4.08), major vascular involvement (HRR 2.20), distal bile duct or pancreatic origin of carcinoma (HRR 1.93), and perioperative blood transfusion of more than 4 U (HRR 1.76). Tumor size (> 2 cm), regional lymph node involvement, and a poor differentiation grade were overall negative factors in univariate analysis but not in the subgroup of ampullary carcinoma. CONCLUSION: Involvement of resection margins, major vascular ingrowth, site of origin of carcinoma, and perioperative blood transfusion were independent prognostic factors for survival after PD. Overall 5-year survival was 31%, and subtotal PD is advocated for all patients with a macroscopically resectable tumor in the pancreatic head region without major vascular involvement, even for those with larger tumors or local lymph node metastasis. Care should be taken to limit the need for perioperative blood transfusions.

Aged↗
PubMed1995

Diagnostic laparoscopy combined with laparoscopic ultrasonography in staging of cancer of the pancreatic head region.

The aim of this study was to assess the additional role of diagnostic laparoscopy combined with laparoscopic ultrasonography in the staging of patients with pancreatic head malignancy. Between January 1993 and June 1994, 73 patients with stage I cancer of the pancreatic head determined by preoperative investigation (endoscopic retrograde cholangiopancreatography and Doppler ultrasonography) were eligible for laparoscopic ultrasonography. The peritoneal cavity was investigated for peritoneal deposits, intrahepatic metastases, malignant infiltration of the portal and superior mesenteric vessels, and N3 lymph node metastases. All patients without histologically proven metastases proceeded to laparotomy. Seventy patients were eligible for evaluation. Sixteen of the 21 patients with distant metastases were diagnosed by laparoscopy with ultrasonography. Forty-nine patients had surgical exploration and trial dissection to assess local resectability. Twenty-nine patients (41 per cent) had resectable pancreatic head tumours. The positive predictive value of local ingrowth as determined by laparoscopic sonography was 93 per cent. Laparotomy was avoided in 19 per cent of patients and the preoperative stage was changed in 41 per cent. Laparoscopy including ultrasonography was effective in staging pancreatic head malignancy.

Humans↗
PubMed1995

Results of pancreaticoduodenectomy for ampullary carcinoma and analysis of prognostic factors for survival.

BACKGROUND: Results of pancreaticoduodenectomy for ampullary carcinoma were evaluated, and prognostic factors for survival were analyzed. METHODS: During the period from 1984 to 1992 67 patients underwent subtotal or total pancreaticoduodenectomy for ampullary carcinoma. All clinicopathologic data and their influence on survival were studied. RESULTS: Subtotal pancreaticoduodenectomy was performed in 62 of 67 patients with a mortality of 6% and a morbidity of 65%; the remaining five patients underwent total pancreaticoduodenectomy. Intraabdominal infection was the most important complication. Resection margins were tumor free in 75% of 67 patients. The overall 5-year survival was 50%. Survival was significantly influenced by the involvement of resection margins. After resection with involved margins 5-year survival was 15% and 60% after resection with free margins (p < 0.001). Tumor size, lymph node involvement, and differentiation grade had limited and not significant influence on survival. CONCLUSIONS: Subtotal pancreaticoduodenectomy is the type of resection of first choice for ampullary carcinoma. Involvement of resection margins was the strongest prognostic factor for survival. Patients with a tumor size larger than 2 cm, with lymph node involvement, or with a poorly differentiated tumor still had a 5-year survival rate greater than 40%. Patients with involved margins might be candidates for studies on adjuvant therapy.

Adenocarcinoma↗
PubMed1995

Laparoscopy and laparoscopic ultrasonography in staging of carcinoma of the esophagus and gastric cardia.

BACKGROUND: The objective of this prospective study was to assess the contribution of laparoscopy combined with laparoscopic ultrasonography (LLU) in the preoperative staging of patients with carcinoma of the esophagus and cardia. STUDY DESIGN: Preoperative LLU was performed in 56 patients who were selected for curative resection of carcinoma of the esophagus (n = 38) or gastric cardia with involvement of the distal esophagus (n = 18) after routine preoperative workup. During LLU, the peritoneal cavity was scrutinized for metastatic disease, and ultrasonography of the liver and celiac axis was performed. In all patients without histologically proven metastases, laparotomy was then performed. RESULTS: The morbidity rate of the procedure was 3.5 percent (two superficial wound infections). In three (5 percent) of the 56 patients, laparotomy was excluded by the presence of intra-abdominal metastases. In three other patients, laparotomy was necessary to confirm the suspected hepatic or peritoneal metastases, or both, because histologic proof was not obtained at laparoscopy. In one patient, LLU failed to detect a small hepatic metastasis in segment VII. The preoperative stage was altered by laparoscopy in nine (17 percent) patients (M1 in six, T4 in three). Laparotomy was avoided in two (11 percent) and the preoperative stage changed in seven patients (41 percent), all of whom had carcinoma of the gastric cardia, as occurred in one (3 percent) and two (6 percent) patients with middle and distal carcinoma of the esophagus, respectively. CONCLUSIONS: Preoperative staging by LLU is of little value in patients with carcinoma of the middle and lower esophagus. The probable role of LLU in the staging of patients with carcinomas of the gastric cardia remains to be confirmed in larger series.

Cardia↗
PubMed1994

Portal vein resection in patients undergoing pancreatoduodenectomy for carcinoma of the pancreatic head.

Of 176 patients with carcinoma of the pancreatic head region 156 underwent standard pancreatoduodenectomy (group 2) and 20 with macroscopic suspicion of invasion of the portal vein or superior mesenteric vein (SMV) underwent pancreatoduodenectomy with partial resection of the portal vein or SMV (group 1). In 16 patients in group 1 end-to-end anastomosis was used for reconstruction of the vein. The morbidity rate in groups 1 and 2 was similar (55 versus 63 per cent). The hospital mortality rate was 15 per cent in group 1 and 7 per cent in group 2 (P = 0.22). Histological examination confirmed tumour invasion of the portal vein or SMV in ten patients in group 1. Invasion of the portal vein or SMV was significantly more frequent in patients with pancreatic cancer than in those with distal bile duct or ampullary carcinoma. Of the 20 patients in group 1 only three underwent curative resection with tumour-free margins. The median survival time after resection of the portal vein or SMV was 8 months; the 2-year survival rate was 19 per cent. Comparison of survival in group 1 with survival in subgroups of patients undergoing standard pancreatoduodenectomy, matched for all histological parameters, showed no significant difference. It is concluded that partial resection of the portal vein or SMV in patients undergoing pancreatoduodenectomy who are suspected of having tumour invasion of the portal vein or SMV does not improve either the rate of curative resection or survival.

Analysis of Variance↗
PubMed1994

Heterogeneity of human gallbladder mucin in bile.

1. Human gallbladder mucin has been implicated to play a role in gallstone disease. In spite of this fact relatively little is known about the structure of human gallbladder mucin. In this study we have investigated the possible heterogeneity of mucin. For this purpose polyclonal and monoclonal antibodies against gallbladder mucin were raised. All antibodies reacted primarily with carbohydrate antigenic determinants. With these antibodies the immunoreactivity of gallbladder mucin from 60 patients with cholesterol gallstones and 20 subjects without stones was screened. In addition, reactivity with several lectins was studied. 2. Considerable heterogeneity was found with both antibody and lectin typing, but there was no significant difference in heterogeneity between mucin from patients with gallstones and control subjects. Immunoblotting revealed that there was similarity between the reaction of the polyclonal antibody and the Helix pomatia agglutinin. All mucin preparations reacting with the polyclonal antibody also bound to Helix pomatia agglutinin. Nineteen of the 21 reacting mucins (90%) were from patients with blood group A (18 patients) or AB (one patient) and expression of A antigen could be demonstrated on the mucin of these patients. The resulting two reacting mucins were from patients with type O. However, expression of the blood group antigen could not account for the lack of reactivity of the mucin of other patients. The Helix pomatia agglutinin partially blocked the reactivity of the polyclonal antibody, whereas anti-A antibody did not show inhibition, indicating that more than only blood group A epitopes were recognized by this antibody. 3. We conclude that considerable patient to patient heterogeneity of human gallbladder mucin exists.(ABSTRACT TRUNCATED AT 250 WORDS)

Antibody Specificity↗
PubMed1994

Haemodynamic effects of pneumoperitoneum for laparoscopic surgery: a comparison of CO2 with N2O insufflation.

We studied the haemodynamic effects of intra-abdominal insufflation with either CO2 (n = 15) or N2O (n = 15) in patients undergoing laparoscopic surgery. Haemodynamic variables were measured at increasing levels of intra-abdominal pressure up to 20 mmHg. In the CO2 group cardiac index decreased from 2.6 +/- 0.6 to 2.0 +/- 0.4 litre min-1 m-2 (mean +/- SD, P < 0.001) and in the N2O group from 2.6 +/- 0.5 to 1.8 +/- 0.4 litre min-1 m-2 (P < 0.001)). In the CO2 group, this was accompanied by increases in mean arterial pressure, systemic vascular resistance index and central venous pressure without change in heart rate. In contrast, during N2O insufflation mean arterial pressure decreased (from 77 +/- 8 to 63 +/- 15 mmHg (P < 0.001)) without change in vascular resistance. No further changes in haemodynamic variables were observed during head-up tilt in both groups. After desufflation mean arterial pressure increased in the N2O group to pre-insufflation levels and cardiac index increased in both groups (P < 0.001), but reached pre-insufflation levels only in the CO2 group. In both groups central venous O2 tension and saturation decreased at maximum intra-abdominal pressure and increased after release of the pneumoperitoneum. The results indicate that laparoscopic insufflation with either CO2 or N2O results in cardiovascular depression. Insufflation with N2O may decrease blood pressure, whereas mean arterial pressure is better preserved with CO2 insufflation.

Adult↗
PubMed1993

Benign biliary strictures. Surgery or endoscopy?

OBJECTIVE: This study compared the results of surgery and endoscopy for benign biliary strictures in one institution, over the same period of time and with the same outcome definitions. SUMMARY BACKGROUND DATA: Surgery is considered the treatment of choice, offering more than 80% long-term success. Endoscopic stenting has been reported to yield similar results and might be a useful alternative. METHODS: In this nonrandomized retrospective study, 101 patients with benign biliary strictures were included. Thirty-five patients were treated surgically and 66 by endoscopic stenting. Patient characteristics, initial trauma, previous repairs, and level of obstruction were comparable in both groups. Surgical therapy consisted of constructing a biliary-digestive anastomosis in normal ductal tissue. Endoscopic therapy consisted of placement of endoprostheses, with trimonthly elective exchange for a 1-year period. RESULTS: Mean length of follow-up was 50 +/- 3.8 and 42 +/- 4.2 months for surgery and endoscopy, respectively. Early complications occurred more frequently in the surgically treated group (p < 0.03). Late complications during therapy, occurred only in the endoscopically treated group. In 46 patients, the endoprostheses were eventually removed. Recurrent stricturing occurred in 17% in both surgical and endoscopic patients. CONCLUSIONS: Surgery and endoscopy for benign biliary strictures have similar long-term success rates. Indications for surgery are complete transections, failed previous repairs, and failures of endoscopic therapy. All other patients are candidates for endoscopic stenting as the initial treatment.

Adult↗