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Featured researches published by H. Obertop.


The New England Journal of Medicine | 1999

Extended Lymph-Node Dissection for Gastric Cancer

J.J. Bonenkamp; J. Hermans; Mitsuru Sasako; K. Welvaart; Ilfet Songun; S. Meyer; JThM Plukker; P. van Elk; H. Obertop; D. J. Gouma; J.J.B. van Lanschot; C. W. Taat; P.W. de Graaf; M.F. von Meyenfeldt; H. W. Tilanus; C.J.H. van de Velde

BACKGROUND Curative resection is the treatment of choice for gastric cancer, but it is unclear whether this operation should include an extended (D2) lymph-node dissection, as recommended by the Japanese medical community, or a limited (D1) dissection. We conducted a randomized trial in 80 Dutch hospitals in which we compared D1 with D2 lymph-node dissection for gastric cancer in terms of morbidity, postoperative mortality, long-term survival, and cumulative risk of relapse after surgery. METHODS Between August 1989 and July 1993, a total of 996 patients entered the study. Of these patients, 711 (380 in the D1 group and 331 in the D2 group) underwent the randomly assigned treatment with curative intent, and 285 received palliative treatment. The procedures for quality control included instruction and supervision in the operating room and monitoring of the pathological results. RESULTS Patients in the D2 group had a significantly higher rate of complications than did those in the D1 group (43 percent vs. 25 percent, P<0.001), more postoperative deaths (10 percent vs. 4 percent, P= 0.004), and longer hospital stays (median, 16 vs. 14 days; P<0.001). Five-year survival rates were similar in the two groups: 45 percent for the D1 group and 47 percent for the D2 group (95 percent confidence interval for the difference, -9.6 percent to +5.6 percent). The patients who had R0 resections (i.e., who had no microscopical evidence of remaining disease), excluding those who died postoperatively, had cumulative risks of relapse at five years of 43 percent with D1 dissection and 37 percent with D2 dissection (95 percent confidence interval for the difference, -2.4 percent to +14.4 percent). CONCLUSIONS Our results in Dutch patients do not support the routine use of D2 lymph-node dissection in patients with gastric cancer.


Gut | 1998

Impact of endoscopic biopsy surveillance of Barrett's oesophagus on pathological stage and clinical outcome of Barrett's carcinoma

J.W. van Sandick; J.J.B. van Lanschot; B.W. Kuiken; G. N. J. Tytgat; G J A Offerhaus; H. Obertop

Background—The efficacy of endoscopic biopsy surveillance of Barrett’s oesophagus in reducing mortality from oesophageal cancer has not been confirmed. Aims—To investigate the impact of endoscopic biopsy surveillance on pathological stage and clinical outcome of Barrett’s carcinoma. Methods—A clinicopathological comparison was made between patients who initially presented with oesophageal adenocarcinoma (n=54), and those in whom the cancer had been detected during surveillance of Barrett’s oesophagus (n=16). Results—The surveyed patients were known to have Barrett’s oesophagus for a median period of 42 months (range 6–144 months). Prior to the detection of adenocarcinoma or high grade dysplasia, 13 of 16 patients (81%) were previously found to have low grade dysplasia. Surgical pathology showed that surveyed patients had significantly earlier stages than non-surveyed patients (p=0.0001). Only one surveyed patient (6%) versus 34 non-surveyed patients (63%) had nodal involvement (p=0.0001). Two year survival was 85.9% for surveyed patients and 43.3% for non-surveyed patients (p=0.0029). Conclusions—The temporal course of histological progression in our surveyed patients supports the theory that adenocarcinoma in Barrett’s oesophagus develops through stages of increasing severity of dysplasia. Endoscopic biopsy surveillance of Barrett’s oesophagus permits detection of malignancy at an early and curable stage, thereby potentially reducing mortality from oesophageal adenocarcinoma.


Gut | 1996

Treatment of bile duct lesions after laparoscopic cholecystectomy.

Jacques J. Bergman; G R van den Brink; E. A. J. Rauws; L. T. De Wit; H. Obertop; Kees Huibregtse; G.N.J. Tytgat; D. J. Gouma

From January 1990 to June 1994, 53 patients who sustained bile duct injuries during laparoscopic cholecystectomy were treated at the Amsterdam Academic Medical Centre. There were 16 men and 37 women with a mean age of 47 years. Follow up was established in all patients for a median of 17 months. Four types of ductal injury were identified. Type A (18 patients) had leakage from cystic ducts or peripheral hepatic radicles, type B (11 patients) had major bile duct leakage, type C (nine patients) had an isolated ductal stricture, and type D (15 patients) had complete transection of the bile duct. Endoscopic retrograde cholangiopancreatography (ERCP) established the diagnosis in all type A, B, and C lesions. In type D lesions percutaneous cholangiography was required to delineate the proximal extent of the injury. Initial treatment (until resolution of symptoms and discharge from hospital) comprised endoscopy in 36 patients and surgery in 26 patients. Endoscopic treatment was possible and successful in 16 of 18 of type A lesions, five of seven of type B lesions, and three of nine of type C lesions. Most failures resulted from inability to pass strictures or leaks at the initial endoscopy. During initial treatment additional surgery was required in seven patients. Fourteen patients underwent percutaneous or surgical drainage of bile collections, or both. After endoscopic treatment early complications occurred in three patients, with a fatal outcome in two (not related to the endoscopic therapy). During follow up six patients developed late complications. All 15 patients with complete transection and four patients with major bile duct leakage were initially treated surgically. During initial treatment additional endoscopy was required in two patients. Early complications occurred in eight patients. During follow up seven patients developed stenosis of the anastomosis or bile duct. Reconstructive surgery in the early postoperative phase was associated with more complications than elective reconstructive surgery. Most type A and B bile duct injuries after laparoscopic cholecystectomy (80%) can be treated endoscopically. In patients with more severe ductal injury (type C and D) reconstructive surgery is eventually required in 70%. Multidisciplinary approach to these lesions is advocated and algorithms for treatment are proposed.


Journal of Clinical Oncology | 2004

Quality of Life After Transhiatal Compared With Extended Transthoracic Resection for Adenocarcinoma of the Esophagus

A. G. E. M. de Boer; J.J.B. van Lanschot; J.W. van Sandick; J. B. F. Hulscher; Peep F. M. Stalmeier; J.C.J.M. de Haes; H. W. Tilanus; H. Obertop; Mirjam A. G. Sprangers

PURPOSE To assess 3 years of quality of life in patients with esophageal cancer in a randomized trial comparing limited transhiatal resection with extended transthoracic resection. PATIENTS AND METHODS Quality-of-life questionnaires were sent at baseline and at 5 weeks; 3, 6, 9, and 12 months; and 1.5, 2, 2.5, and 3 years after surgery. Physical and psychological symptoms, activity level, and global quality of life were assessed with the disease-specific Rotterdam Symptom Checklist. Generic quality of life was measured with the Medical Outcomes Study Short Form-20. RESULTS A total of 199 patients participated. Physical symptoms and activity level declined after the operation and gradually returned toward baseline within the first year (P < .01). Psychological well-being consistently improved after baseline (P < .01), whereas global quality of life showed a small initial decline followed by continuous gradual improvement (P < .01). Quality of life stabilized in the second and third year. Three months after the operation, patients in the transhiatal esophagectomy group (n = 96) reported fewer physical symptoms (P = .01) and better activity levels (P < .01) than patients in the transthoracic group (n = 103), but no differences were found at any other measurement point. For psychological symptoms and global quality of life, no differences were found at any follow-up measurement. A similar pattern was found for generic quality of life. CONCLUSION No lasting differences in quality of life of patients who underwent either transhiatal or transthoracic resection were found. Compared with baseline, quality of life declined after the operation but was restored within a year in both groups.


British Journal of Surgery | 2004

Mortality and morbidity of planned relaparotomy versus relaparotomy on demand for secondary peritonitis

Bas Lamme; Marja A. Boermeester; E. J. T. Belt; J. W. O. van Till; Dirk J. Gouma; H. Obertop

Planned relaparotomy (PR) and relaparotomy on demand (ROD) are both frequently used in the treatment of secondary peritonitis. The aim of this study was to evaluate the mortality, morbidity and long‐term outcome associated with PR compared with ROD in patients with secondary peritonitis admitted to a university hospital.


Annals of Surgery | 1997

Prospective, randomized trial on the effect of cyclic versus continuous enteral nutrition on postoperative gastric function after pylorus-preserving pancreatoduodenectomy.

M. I. van Berge Henegouwen; L.M.A. Akkermans; T.M. van Gulik; Ad Masclee; Thybout M. Moojen; H. Obertop; D. J. Gouma

OBJECTIVE The effect of a cyclic versus a continuous enteral feeding protocol on postoperative delayed gastric emptying, start of normal diet, and hospital stay was assessed in patients undergoing pylorus-preserving pancreatoduodenectomy (PPPD). SUMMARY BACKGROUND DATA Delayed gastric emptying occurs in approximately 30% of patients after PPPD and causes prolonged hospital stay. Enteral nutrition through a catheter jejunostomy is used to provide postoperative nutritional support. Enteral infusion of fats and proteins activates neurohumoral feedback mechanisms and therefore can potentially impair gastric emptying and prolong postoperative gastroparesis. METHODS From September 1995 to December 1996, 72 consecutive patients underwent PPPD at the Academic Medical Center, Amsterdam. Fifty-seven patients were included and randomized for either continuous (CON) jejunal nutrition (0-24 hr; 1500 kCal/24 hr) or cyclic (CYC) enteral nutrition (6-24 hr; 1125 kCal/18 hr). Both groups had an equal caloric load of 1 kCal/min. The following parameters were assessed: days of nasogastric intubation, days of enteral nutrition, days until normal diet was tolerated orally, and hospital stay. On postoperative day 10, plasma cholecystokinin (CCK) levels were measured during both feeding protocols. RESULTS Nasogastric intubation was 9.1 days in the CON group (n = 30) and 6.7 days in the CYC group (n = 27) (not statistically significant). First day of normal diet was earlier for the CYC group (15.7 vs. 12.2 days, p < 0.05). Hospital stay was shorter in the CYC group (21.4 vs. 17.5 days, p < 0.05). CCK levels were lower in CYC patients, before and after feeding, compared with CON patients (p < 0.05). CONCLUSIONS Cyclic enteral feeding after PPPD is associated with a shorter period of enteral nutrition, a faster return to a normal diet, and a shorter hospital stay. Continuously high CCK levels could be a cause of prolonged time until normal diet is tolerated in patients on continuous enteral nutrition. Cyclic enteral nutrition is therefore the feeding regimen of choice in patients after PPPD.


The American Journal of Gastroenterology | 2002

Prospective evaluation of anorectal function after total mesorectal excision for rectal carcinoma with or without preoperative radiotherapy

P. van Duijvendijk; J. F. M. Slors; C. W. Taat; W.F. van Tets; G. van Tienhoven; H. Obertop; Guy E. Boeckxstaens

Abstract OBJECTIVE: Anorectal function is greatly disturbed after rectal surgery with or without radiotherapy (RT). To clarify the underlying mechanisms, we designed a prospective study to evaluate the effect of RT and surgery on anorectal function and clinical outcome of patients with a rectal carcinoma. METHODS: Thirty-four patients with a rectal carcinoma participated in this study. They filled out a symptom questionnaire and underwent anal manometry, anal and rectal mucosal electrosensitivity testing, and a rectal barostat, before surgery, 4 and 12 months postoperatively. Thirteen patients were lost to follow-up, 14 underwent surgery alone (total mesorectal excision [TME]), and seven also received RT (RT + TME). RESULTS: Functional outcome was disappointing in both groups, with at 4 months a significantly higher defecation frequency after RT + TME as compared with TME. Anal sphincter function and rectal sensitivity to pressure-controlled distention were not affected by either treatment. Rectal compliance, however, was significantly reduced after RT + TME at 4 and 12 months, resulting in lower rectal volumes at the thresholds for first sensation and desire to defecate. Rectal but not anal mucosal electrosensitivity was higher after TME + RT. CONCLUSIONS: Anorectal function after rectal surgery with or without RT is greatly hampered because of a decreased rectal compliance. After 12 months, partial improvement is shown, especially in the absence of RT.


Gastrointestinal Endoscopy | 1997

Prospective study on the value of endosonographic follow-up after surgery for esophageal carcinoma

P. Fockens; Cg Manshanden; J.J.B. van Lanschot; H. Obertop; G. N. J. Tytgat

BACKGROUND Half of the patients who undergo surgery for cancer of the esophagus or gastric cardia present with recurrent disease within 2 years after the operation. We investigated the value of endosonography for the early detection of recurrent disease. METHODS Forty-three patients entered a follow-up protocol in which endosonography was performed every 6 months within the first 2 years after resection. RESULTS During 16 of a total of 66 examinations, suspicious abnormalities were found. In three patients free fluid was seen, but recurrence could not be confirmed during follow-up. In eight patients suspicious lymph nodes were seen; six died within 6 months, one was alive with a proven recurrence at 6 months, and one was alive without recurrence at 22 months. In five patients focal wall-thickening or a mass was seen; three died within 6 months, and two were alive with a proven recurrence at 2 and 5 months. After exclusion of free fluid, the positive predictive value of abnormalities on endoscopic ultrasonography (EUS) was 92%. CONCLUSIONS Endosonography, performed at 6-month intervals after resection of cancer of the esophagus or gastric cardia, is accurate in the early detection of locoregional recurrent disease. Two thirds of the patients were still without symptoms when the recurrence was found.


Scandinavian Journal of Gastroenterology | 1996

Laparoscopic ultrasonography for staging of gastrointestinal malignancy.

D. J. Gouma; L. Th. de Wit; E.J.M. Nieveen van Dijkum; O.M. van Delden; W. A. Bemelman; E. A. J. Rauws; J.J.B. van Lanschot; H. Obertop

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.


Annals of Surgery | 1998

Cytology of peritoneal lavage performed during staging laparoscopy for gastrointestinal malignancies: is it useful?

E.J.M. Nieveen van Dijkum; Patrick D. J. Sturm; L. T. de Wit; J Offerhaus; H. Obertop; D. J. Gouma

OBJECTIVE To evaluate the potential benefit of cytology of the peritoneal lavage obtained during diagnostic laparoscopy for staging gastrointestinal (GI) malignancies. SUMMARY BACKGROUND DATA Peritoneal lavage is a simple procedure that can be performed during laparotomy for GI tumors. Tumor cells in the lavage fluid are thought to indicate intraperitoneal tumor seeding and to have a negative effect on survival. For this reason, peritoneal lavage is frequently added to diagnostic laparoscopy for staging GI malignancies. METHODS Patients who underwent peritoneal lavage during laparoscopic staging for GI malignancies between June 1992 and September 1997 were included. Lavage fluids were stained using Giemsa and Papanicolaou methods. Cytology results were correlated with the presence of metastases and tumor ingrowth found during laparoscopy and with survival. RESULTS Cytology of peritoneal lavage was performed in 449 patients. Tumor cells were found in 28 patients (6%): 8/87 with an esophageal tumor, 2/32 with liver metastases, 11/72 with a proximal bile duct tumor, 7/236 with a periampullary tumor, and none in 7 and 15 patients with a primary liver tumor or pancreatic body or tail tumor, respectively. In 19 of the 28 patients (68%) in whom tumor cells were found, metastatic disease was detected during laparoscopy, and 3 of the 28 patients had a false-positive (n = 1) or a misleading positive (n = 2) lavage result. Therefore, lavage was beneficial in only 6/449 patients (1.3%); in these patients, the lavage result changed the assessment of tumor stage and adequately predicted irresectable disease. Univariate analysis showed a significant survival difference between patients in whom lavage detected tumor cells and those in whom it did not, but multivariate analysis revealed that these survival differences were caused by metastatic or ingrowing disease. CONCLUSION Cytology of peritoneal lavage with conventional staining should no longer be performed during laparoscopic staging of GI malignancies because it provides an additional benefit in only 1.3% of patients and has limited prognostic value for survival in this group of patients.

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D. J. Gouma

University of Amsterdam

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J.W. van Sandick

Netherlands Cancer Institute

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L. T. de Wit

University of Amsterdam

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O.R.C. Busch

University of Amsterdam

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