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Featured researches published by Oliver Schwandner.


Surgical Endoscopy and Other Interventional Techniques | 1999

The role of conversion in laparoscopic colorectal surgery: Do predictive factors exist?

Oliver Schwandner; Thomas H. K. Schiedeck; Hans-Peter Bruch

AbstractBackground: This study was performed to analyze the reasons for conversion of laparoscopic colorectal procedures to open surgery and to identify risk factors. Methods: All patients who underwent laparoscopic colorectal surgery at our institution were enrolled in a prospective trial. The causes of conversion were analyzed. Statistical analysis, including a logistic regression model, was performed to identify factors that would predict an increased risk of conversion. Results: A total of 300 laparoscopic or laparoscopic-assisted procedures for both benign and malignant diseases were performed within 5 years. Mean patient age was 61.4 years (range, 17–93). There were 218 women and 82 men. Major complications occurred in 8.6%, and 30-day-mortality rate was 1.1%. Postoperative hospitalization was 13.9 days (range, 6–47). Conversion occurred in 22 cases (7.3%). The mean age of the converted group was 64.7 years (range, 31–93). Postoperative hospital stay was 15.0 days (range, 10–25). The main reasons for conversion to open surgery were inflammation, obesity, anesthetic problems, technical difficulties, intraoperative complications, and intraoperative decisions concerning oncological resection. The conversion rate was 14.6% in patients who underwent sigmoid resection for diverticular disease. By univariate analysis, statistically significant factors defining a higher risk of conversion were male gender (p= 0.0029), age from 55 to 64 years (p= 0.0015), extreme body status (p= 0.0001), and diagnosis of diverticular disease (p= 0.0011). According to the logistic regression model, all four factors combined would give a probability of conversion of 70.3%. Conclusions: The risk factors contributing to the possibility of conversion included male gender, age between 55 and 64 years, extreme body status, and diverticular disease. Using these data, patients with an increased likelihood of conversion can be identified. However, if conversion is necessary, laparoscopic colorectal surgery can be safely applied to the patients with no additional morbidity.


Surgical Endoscopy and Other Interventional Techniques | 2004

Laparoscopic colorectal surgery in obese and nonobese patients: Do differences in body mass indices lead to different outcomes?

Oliver Schwandner; S. Farke; Thomas H. K. Schiedeck; Hans-Peter Bruch

BackgroundThe aim of this prospective study was to compare the outcome of laparoscopic colorectal surgery in obese and nonobese patients.MethodsAll patients who underwent laparoscopic surgery for both benign and malignant disease within the past 5 years were entered into the prospective database registry. Body mass index (BMI; kg/m2) was used as the objective measure to indicate morbid obesity. Patients with a BMI >30 were defined as obese, and patients with a BMI <30 were defined as nonobese. The parameters analyzed included age, gender, comorbid conditions, diagnosis, procedure, duration of surgery, transfusion requirements, conversion rate, overall morbidity rate including major complications (requiring reoperation), minor complications (conservative treatment) and late-onset complications (postdischarge), stay on intensive case unit, hospitalization, and mortality. For objective evaluation, only laparoscopically completed procedures were analyzed. Statistics included Student’s t test and chi-square analysis. Statistical significance was assessed at the 5% level (p < 0. 05 statistically significant).ResultsA total of 589 patients were evaluated, including 95 patients in the obese group and 494 patients in the nonobese group. There was no significant difference in conversion rate (7.3% in the obese group vs 9.5% in the nonobese group, p > 0.05) so that the laparoscopic completion rate was 90.5% (n = 86) in the obese and 92.7% (n = 458) in the nonobese group. The rate of females was significantly lower among obese patients (55.8% in the obese group vs 74.2% in the nonobese group, p = 0.001). No significant differences were observed with respect to age, diagnosis, procedure, duration of surgery, and transfusion requirements (p > 0.05). In terms of morbidity, there were no significant differences related to overall complication rates with respect to BMI (23.3% in the obese group vs 24.5% in the nonobese group, p > 0.05). Major complications were more common in the obese group without showing statistical significance (12.8% in the obese group vs 6.6% in the nonobese group, p = 0.078). Conversely, minor complications were more frequently documented in the nonobese group (8.1% in the obese group vs 15.5% in the nonobese group, p = 0.080). In the postoperative course, no differences were documented in terms of return of bowel function, duration of analgesics required, oral feeding, and length of hospitalization (p > 0.05).ConclusionThese data indicate that laparoscopic colorectal surgery is feasible and effective in both obese and nonobese patients. Obese patients who are thought to be at increased risk of postoperative morbidity have the similar benefit of laparoscopic surgery as nonobese patients with colorectal disease.


Diseases of The Colon & Rectum | 1999

Advanced age : Indication or contraindication for laparoscopic colorectal surgery?

Oliver Schwandner; Thomas H. K. Schiedeck; Hans-Peter Bruch

PURPOSE: It has been proposed that laparoscopic colorectal surgery offers several benefits to patients. The aim of this study was to evaluate particularly whether older patients can benefit by laparoscopic colorectal procedures or if minimally invasive procedures are contraindicated. METHODS: All patients who underwent elective surgery were divided into age-related groups: patients 50 years of age or younger, patients ranging from 51 to 70 years of age, and patients older than 70 years. The groups by age were compared with each other relative to their cardiopulmonary status, indication, procedure, conversion, morbidity, mortality, duration of surgery, perioperative blood transfusion, stay on the intensive care unit, and hospitalization. Statistical analysis included univariate analysis by chi-squared tests and Studentst-tests comparing patients older than 70 years with patients 50 years of age or younger and with patients ranging from 51 to 70 years of age (statistical significance was defined asP<0.05). RESULTS: Within five years 298 patients (male/female ratio, 0.38) underwent a laparoscopic or laparoscopic-assisted colorectal procedure. Of these, 95 (31.9 percent) patients were older than 70 years, 138 (46.3 percent) patients ranged from 51 to 70 years of age, and 65 (21.8 percent) patients were 50 years of age or younger. Pathologic findings in cardiopulmonary function increased with age. There were no statistically significant differences among the younger, middle-aged, and older patients relative to the incidence of conversion (3.1vs. 9.4vs. 7.4 percent, respectively), major complications (4.6vs. 10.1vs. 9.5 percent, respectively), minor complications (12.3vs. 15.2vs. 12.6 percent, respectively) or total laparotomy rate (7.7vs. 12.3vs. 12.6 percent, respectively).P>0.05 for all comparisons. However, duration of surgery, stay on the intensive care unit, and postoperative hospitalization were significantly prolonged in patients older than 70 years (P<0.05 for all comparisons) but were reduced during the five years of experience with these procedures. CONCLUSIONS: If preoperative assessment of comorbid conditions and perioperative care was ensured, laparoscopic procedures were shown to be safe options in the elderly. The outcome of laparoscopic colorectal surgery in patients older than 70 years is similar to that noted in younger patients. Advanced age is no contraindication for laparoscopic colorectal surgery.


International Journal of Colorectal Disease | 1999

A case-control-study comparing laparoscopic versus open surgery for rectosigmoidal and rectal cancer.

Oliver Schwandner; Thomas H. K. Schiedeck; C. Killaitis; Hans-Peter Bruch

Abstract This study compared laparoscopic with open surgery for the cure of cancer of the rectosigmoid and rectum. Results of surgery, postoperative recovery, and oncological follow-up were compared between 32 laparoscopic curative procedures (19 laparoscopic-assisted anterior resections for cancer of the rectosigmoid or upper rectum and 13 laparoscopic abdominoperineal resections for low rectal cancer) and 32 controls matched for age, UICC stage, tumor site, and type of resection who underwent open surgery during the same observation period. Morbidity was identical after laparoscopic and open resection (31.3%). Surgery was equally radical in the two groups regarding yield of lymph nodes and lateral and distal margins. Survival, recurrence, and cancer-related mortality showed no statistical differences. There was no port-site recurrence. The benefits of laparoscopic surgery were shown with a reduction in perioperative blood transfusion and earlier return of bowel function. However, the operative time was significantly increased in the laparoscopic group. This study shows that laparoscopic surgery for the cure of colorectal cancer is technically feasible, and that oncological short-term outcome does not differ from the results achieved by open techniques. However, prospective randomized trials are mandatory to evaluate the definite role of laparoscopic surgery for malignancy.


Langenbeck's Archives of Surgery | 1999

Actual standards and controversies on operative technique and lymph-node dissection in colorectal cancer.

Hans-Peter Bruch; Oliver Schwandner; Thomas H. K. Schiedeck; Uwe J. Roblick

Background: Radical lymphadenectomy for colorectal cancer according to its arterial supply seems to remove potentially me-tastatic lymph nodes and highlights the impact on prognosis. Standards and controversies: Systematic lymph-node dissection in colorectal cancer requires knowledge of normal anatomy of lymphatic drainage and spreading of lymph-node metastases. Oncological standards of curative surgery for colorectal cancer include en bloc resection, no-touch isolation technique, primary ligation of the vessels and systematic lymphadenectomy. In rectal cancer, total mesorectal excision and irrigation of the rectal stump is mandatory. Potential improvements in prognosis achieved by extended lymph-node dissection have to compete with procedure-related morbidity. High-tie ligation of the inferior mesenteric artery is a controversial issue. Prediction of prognosis is essential for planning a treatment schedule for patients. Conclusions: At present, clinicopathological stage is the single most reliable factor in prediction of outcome. New encouraging methods for detecting micrometastases of lymph nodes and new surgical technologies such as immune corrective surgery are challenging and have to be critically assessed. The results of laparoscopic surgery for the cure of colorectal cancer have to be proven within prospective randomised trials.


Digestive Surgery | 1999

Laparoscopic Colorectal Surgery:A Five-Year Experience

Hans-Peter Bruch; Thomas H. K. Schiedeck; Oliver Schwandner

Objective: The aim of this study was to assess the feasibility and outcome of 300 laparoscopic colorectal procedures performed within 5 years for both benign and malignant disorders. The specific purpose was to identify the impact of the learning curve on reducing morbidity and on improving the outcome of laparoscopic colorectal surgery. Patients and Methods: All cases were divided into 3 groups: the first 100, the second 100 and the third 100 procedures were analyzed. Statistical analysis was performed by Student’s t test and χ2 test. Results: The laparoscopic procedure had to be converted to open surgery in 22 cases (mean conversion rate 7.3%). Thus, a total of 278 procedures could be performed laparoscopically. The mean major complication rate was 8.6%, minor complications occurred in 9.7%. The overall morbidity rate was 18.3%. In 44 cases, laparoscopic resections were performed for the cure of colorectal malignancy. The mean lymph node harvest was 12.8 nodes, no port-site recurrence was documented at a mean follow-up of 22 months. Analyzing our 5-year experience, the incidence of conversion showed a decline from 8.0% (1st and 2nd 100) to 6.0% in the last 100 procedures (p > 0.05). The major complication rate was significantly decreased from 15 to 6.0% (1st vs. 2nd 100) and was 5.0% in the 3rd group. The minor complication rate, overall morbidity rate and laparotomy rate have also been reduced (p > 0.05). The duration of surgery was shortened from 251.4 to 213.5 min (1st vs. 2nd 100, p < 0.05) and was 196.9 min in the last 100 procedures. Postoperative hospital stay was decreased from 16.3 to 14.3 days (1st 100 vs. 2nd 100, p > 0.05) and could be shortened to 11.2 days (2nd vs. 3rd 100, p < 0.05). Conclusion: With increasing experience, laparoscopic colorectal surgery can be performed with reduced morbidity and improved outcome. To evaluate the role of laparoscopic colorectal procedures, particularly for the cure of malignancy, prospective randomized trials are necessary.


International Journal of Colorectal Disease | 2005

Laparoscopic colectomy for diverticulitis is not associated with increased morbidity when compared with non-diverticular disease

Oliver Schwandner; S. Farke; Hans-Peter Bruch

Background and aimsIt was the aim of this prospective study to compare the outcome of laparoscopic sigmoid and anterior resection for diverticulitis and non-diverticular disease.Patients and methodsAll patients who underwent laparoscopic colectomy for benign and malignant disease within a 10-year period were entered into the prospective PC database registry. For outcome analysis, patients who underwent laparoscopic sigmoid and anterior resection for diverticular disease were compared with patients who underwent the same operation for non-inflammatory (non-diverticular) disease. The parameters analyzed included age, gender, co-morbid conditions, diagnosis, procedure, duration of surgery, transfusion requirements, conversion, morbidity including major (requiring reoperation), minor (conservative treatment) and late-onset (postdischarge) complications, stay in the ICU, hospitalization, and mortality. For objective evaluation, only laparoscopically completed procedures were analyzed. Statistics included Student’s t-test and chi-square analysis (p<0.05 was considered statistically significant).ResultsA total of 676 patients were evaluated including 363 with diverticular disease and 313 with non-inflammatory disease. There were no significant differences in conversion rates (6.6 vs. 7.3%, p>0.05), so that the laparoscopic completion rate was 93.4% (n=339) in the diverticulitis group and 92.7% (n=290) in the non-diverticulitis group. The two groups did not differ significantly in age or presence of co-morbid conditions (p>0.05). In the diverticulitis group, recurrent diverticulitis (58.4%), and complicated diverticulitis (27.7%) were the most common indications, whereas in the non-diverticulitis group, outlet obstruction by sigmoidoceles (30.0%) and cancer (32.4%) were the main indications. The most common procedure was laparoscopic sigmoid resection, followed by sigmoid resection with rectopexy and anterior resection. No significant differences were documented for major complications (7.4 vs. 7.9%), minor complications (11.5 vs. 14.5%), late-onset complications (3.0 vs. 3.5), reoperation (8.6 vs. 9.3%) or mortality (0.6 vs. 0.7%) between the two groups (p>0.05). In the postoperative course, no differences were noted in terms of stay in the ICU, postoperative ileus, parenteral analgesics, oral feeding, and length of hospitalization (p>0.05).ConclusionThese data indicate that laparoscopic sigmoid and anterior resection can be performed with acceptable morbidity and mortality for both diverticular disease and non-diverticular disease. The results show in particular that laparoscopic resection for inflammation is not associated with increased morbidity.


Langenbeck's Archives of Surgery | 2005

Rectal prolapse: which surgical option is appropriate?

Thomas H. K. Schiedeck; Oliver Schwandner; J. Scheele; S. Farke; Hans-Peter Bruch

Numerous surgical procedures have been suggested to treat rectal prolapse. In elderly and high-risk patients, perineal approaches such as Delorme’s procedure and perineal rectosigmoidectomy (Altemeier’s procedure) have been preferred, although the incidence of recurrence and the rate of persistent incontinence seem to be high when compared with transabdominal procedures. Functional results of transabdominal procedures, including mesh or suture rectopexy and resection–rectopexy, are thought to be associated with low recurrence rates and improved continence. Transabdominal procedures, however, usually imply rectal mobilization and fixation, colonic resection, or both, and some concern is voiced that morbidity, in terms of infection or leakage, and mortality could be increased. If we focus on surgical outcome, our own experience of laparoscopic resection–rectopexy for rectal prolapse shows that the laparoscopic approach is safe and effective, and functional results with respect to recurrence are favorable. However, the controversy “which operation is appropriate?” cannot be answered definitely, as a clear definition of rectal prolapse, the extent of a standardized diagnostic assessment, and the type of surgical procedure have not been identified in published series. Randomized trials are needed to improve the evidence with which the optimal surgical treatment of rectal prolapse can be defined.


International Journal of Colorectal Disease | 2002

p21, p27, cyclin D1, and p53 in rectal cancer: immunohistology with prognostic significance?

Oliver Schwandner; Hans-Peter Bruch; Rainer Broll

Abstract.Background and aims: This study examined the prognostic value of the cyclin-dependent kinase inhibitors p21Waf1/Cip1 and p27Kip1, and the cell cycle regulating proteins cyclin D1 and p53 after curative surgery for rectal cancer. Patients and methods: Formalin-fixed, paraffin-embedded tissue samples of 160 rectal carcinomas resected curatively within a 5-year period were used. Immunohistochemical analysis used monoclonal antibodies p21Waf1/Cip1 (clone SX118), p27Kip1 (clone SX53G8), cyclin D1 (clone DCS-6), and p53 (DO-1). Positive nuclear protein expression was assessed at the 10% level. Results of immunohistochemistry were studied for correlation with clinical and histopathological data of the prospective tumor registry including recurrence and patient survival. Results: Of the 160 rectal carcinomas 36% were p21Waf1/Cip1 positive, 44% p27Kip1 positive, 48% cyclin D1 positive, and 39% p53 positive. The p21Waf1/Cip1 staining pattern was correlated with p27Kip1 and p53 expression and with UICC stage and lymph node status. p53 status was not correlated to any clinical or histopathological variable. p27Kip1 expression was associated with tumor size and cyclin D1 expression. Tumor progression caused by local and distant recurrence occurred in 20%. p21Waf1/Cip1, p27Kip1, and p53 were strong predictors of recurrence. p21Waf1/Cip1 and p53 but not p27Kip1 were independently correlated with disease-free survival. UICC stage was independently related to both recurrence and survival. The best prognosis was in p21Waf1/Cip1 positive and p53 negative rectal carcinomas. Conclusions: Reflecting tumor biology by immunohistochemical assessment of cell cycle regulators, p21Waf1/Cip1 and p53 were independently predictive of prognosis in rectal cancer, and p27Kip1 was independently related to recurrence. However, cyclin D1 had no independent relationship to prognosis. Clinically, UICC stage was a strong predictor of prognosis after curative surgery for rectal cancer.


Langenbeck's Archives of Surgery | 2001

Prognostic significance of free gastrointestinal tumor cells in peritoneal lavage detected by immunocytochemistry and polymerase chain reaction

Rainer Broll; Weschta M; Windhoevel U; Berndt S; Oliver Schwandner; Uwe J. Roblick; Thomas H. K. Schiedeck; Schimmelpenning H; Hans-Peter Bruch; Michael Duchrow

Abstract. Aims: The aim of our study was to identify tumor cells in peritoneal lavage comparatively with immunocytochemistry (ICC) and half-nested reverse transcriptase-polymerase chain reaction (RT-PCR) using carcinoembryonic antigen (CEA) as marker and to evaluate their prognostic significance. Patients and methods: In 75 patients who underwent surgery for a carcinoma of the colorectum (n=49), stomach (n=17) or pancreas (n=9) and 13 patients with an abdominal aortic aneurysm (control group) the abdomen was irrigated with saline solution immediately after laparotomy. Cells were separated by Ficoll-density centrifugation and divided into 2 equal volumes for ICC and RT-PCR. For ICC cells were spun onto slides by cytospin centrifugation and stained with a monoclonal antibody (mab) against CEA using the APAAP method. For RT-PCR total RNA was extracted from the cells, transcribed into cDNA and amplified with CEA-specific primers. Lavages of 13 patients with an abdominal aortic aneurysm and blood samples of 6 healthy donors served as controls. Results: Immunostained tumor cells were found in peritoneal lavage in 23% (17/75) of all patients, whereas 63% (47/75) of patients gave a positive result by RT-PCR analysis. In the control group (n=13) no patient presented with tumor cells in ICC, however 5 of 13 (38%) showed amplified CEA-mRNA by RT-PCR, and so did one of six blood samples. Using ICC technique, we found significant correlations between detection rates and pT-, pN-, pM-categories as well as tumor stage. On the contrary, by RT-PCR significant correlations were observed only between pT- and pM-categories and detection rates. Detection of tumor cells in peritoneal lavage with both techniques was associated with poor prognosis. Moreover, these tumor cells are an independent prognostic factor and may have an influence on the development of peritoneal carcinomatosis. Conclusion: ICC is a useful method for detection of tumor cells in peritoneal lavage. In contrast, half-nested RT-PCR cannot be recommended, as the detection rates are unproportionally high, obviously as a result of CEA-mRNA expression in nontumor cells.

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Ayman Agha

University of Regensburg

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