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F Köckerling

Publications and source records attributed to F Köckerling.

At least 19 recordsLinked to original sources

Importance of conversion for results obtained with laparoscopic colorectal surgery.

PURPOSE: The need for a conversion is a problem inherent in laparoscopic surgery. The present study points up the significance of conversion for the results obtained with laparoscopic colorectal surgery and identifies the risk factors that establish the need for conversion. METHOD: The study took the form of a multicentric, prospective, observational study within the Laparoscopic Colorectal Surgery Study Group. A total of 33 institutions in Germany, Austria, and Switzerland participated. The study period was 3.5 years. Cases were documented with the aid of a standardized questionnaire. RESULTS: Within the framework of the Laparoscopic Colorectal Surgery Study Group, a total of 1,658 patients were recruited to a multicenter study over a period of three and one-half years (from August 1, 1995 to February 1, 1999). The observed conversion rate was 5.2 percent (n = 86). The patients requiring a conversion were significantly heavier (body mass index, 26.5 vs. 24.9) than those undergoing pure laparoscopy. Resections of the rectum were associated with a higher risk for conversion (20.9 vs. 13 percent). Intraoperative complications occurred significantly more frequently in the conversion group (27.9 vs. 3.8 percent). The duration of the operation was significantly increased after conversion in a considerable proportion of the procedures performed. Postoperative morbidity (47.7 vs. 26.1 percent), mortality (3.5 vs. 1.5 percent), recovery time, and postoperative hospital stay were all negatively influenced by conversion, in part significantly. Institutions with experience of more than 100 laparoscopic colorectal procedures proved to have a significantly lower conversion rate than those with experience of fewer than 100 such interventions (4.3 vs. 6.9 percent). CONCLUSION: Although, of itself, conversion is not considered to be a complication of laparoscopic surgery, it is true that the postoperative course after conversion is associated with appreciably poorer results in terms of morbidity, mortality, convalescence, blood transfusion requirement, and postoperative hospital stay. The importance of experience in laparoscopic surgery can be demonstrated on the basis of the conversion rates. Careful patient selection oriented to the experience of the surgeon is required if we are to keep the conversion, morbidity, and mortality rates of laparoscopic colorectal procedures as low as possible.

Age Distribution↗

Experience as a factor influencing the indications for laparoscopic colorectal surgery and the results.

BACKGROUND: The influence of experience on the results of treatment with laparoscopic surgery is indisputable. The establishment of indications and contraindications is relative, and varies depending on the experience of the surgeon. Learning curves have been described for a number of laparoscopic interventions, in particular laparoscopic cholecystectomy. The current prospective multicenter study investigates, among other things, the interrelation between experience and the results of treatment using laparoscopic colorectal surgery. The study makes no pronouncements on the long-term results achieved in patients with colorectal carcinoma who underwent an operation with curative intent, although relevant data were indeed collected. RESULTS: Between August 1, 1995 and February 1, 1999, a total of 1,658 patients were recruited to the prospective multicenter study initiated by the Laparoscopic Colorectal Surgery Study Group. To investigate the influence of surgical experience, two groups were formed. Group A comprised all the institutions and surgeons with experience of more than 100 laparoscopic colorectal operations. Group B contained institutions and surgeons with experience of fewer than 100 such interventions. The results of this study clearly show that in Group A, significantly more procedures involving the rectum were performed (26.7% vs 9.5%), and significantly more carcinomas were surgically managed (37.3% vs 17.3%). Despite this significantly higher level of technically difficult procedures in the patient population of group A, which was comparable in terms of age, gender, height, and weight with the patient in group B, the postoperative mortality and morbidity was, with the exception of urinary tract infections, identical between the two groups. Conversion to open surgery was significantly less frequent in group A (4.3% vs 6.9%), and, finally, the duration of the procedures performed by the more experienced surgeons of group A was appreciably shorter than in institutions with a smaller frequency of such operations. CONCLUSIONS: Laparoscopic colorectal surgery is very demanding, and can be performed with low morbidity and mortality rates only by a surgeon with above-average experience with this type of surgery and a large caseload of laparoscopic colorectal procedures. The learning curve for such procedures is appreciably longer than for other laparoscopic operations. With increasing experience, technically more demanding operations, including radical oncologic rectal laparoscopic procedures, can be performed with appreciably reduced operating times and conversion rates, but with no increase in morbidity or mortality.

Adult↗

Efficacy of surgical measures in preventing port-site recurrences in a porcine model.

BACKGROUND: Port-site recurrences are serious complications of laparoscopy performed for cancer. Incidences reported in the literature vary between 0% and 21%, suggesting an influence of the surgeon. METHODS: The aim of this experimental, prospective, randomized, single-blind study was to investigate the influence that the quality surgery has on the incidence of port-site recurrences. After a 12-mmHg carbon dioxide (CO2) pneumoperitoneum was created, 10(7) human HeLa cell were injected into the peritoneal cavity of 18 pigs, creating a xenogeneic tumor. Laparoscopic sigmoid resections then were performed using four trocars and a transanal double-stapling technique. The following protective measures were applied in nine animals: trocar fixation, prevention of gas leaks, rinsing of instruments with povidone-iodine, minilaparotomy protection, rinsing of trocars before removal, peritoneal closure, and rinsing of all wounds with povidoneiodine. Surgeons and type of procedures were randomized. After 4 weeks, the animals were killed and all portsites excised. Blinded immunohistologic analysis with antihuman pancytokeratin antibody was performed. RESULTS: Tumor recurrence was present in 23 of 36 port sites (63.8%) in the control group, but only in 5 of 36 port sites (13.8%) in the group that received protective measures (p = 0.002; Fisher's exact test). No peritoneal carcinosis nor anastomotic recurrences were observed. CONCLUSION: These results strongly suggest that the quality of surgical technique has an influence on the incidence of port-site recurrences. From now on, we propose to use these protective measures routinely in cancer laparoscopy.

Animals↗

Decreased expression of p27 protein is associated with advanced tumor stage in hepatocellular carcinoma.

Reduced expression of the cyclin-dependent kinase inhibitor p27 has previously been correlated with fatal clinical outcome in some tumors, including gastric, breast, and prostate cancers. For hepatocellular carcinoma, the findings are equivocal. In situ hybridization and immunohistochemistry were performed on a series of 203 curatively (R0) resected hepatocellular carcinomas and in corresponding non-cancerous liver tissue to detect p27. Patients receiving liver transplantation were excluded. The results were correlated with histopathological stage according to the UICC system, Edmondson grade, several other histopathological factors of possible prognostic significance, and finally patient survival. Whereas p27 mRNA was expressed homogeneously in all carcinomas examined, the p27 protein was found in various amounts. The labeling index of p27 protein was significantly lower in advanced stages of the disease (P < 0.001, chi(2) = 28.1). We observed decreased p27 protein in higher pT categories (P < 0.001, chi(2) = 24.7) and in multiple tumor nodules (P < 0.001, chi(2) = 9.3). Multivariate Cox survival analysis identified age, co-existing cirrhosis, and Edmondson grade as independent prognostic factors. We conclude that evaluation of p27 in hepatocellular carcinoma is useful to predict stage of disease and may have clinical significance, e.g., in predicting optimal therapeutic regimes.

Adult↗

p53 mutation pattern in hepatocellular carcinoma in workers exposed to vinyl chloride.

BACKGROUND: Vinyl chloride (VC) is a known animal and human carcinogen that is associated with liver angiosarcoma and most likely also with hepatocellular carcinoma (HCC) in humans. METHODS: The authors examined the presence of p53 gene mutations in 18 HCC specimens from patients with known exposure to VC (median, 8883 parts per million-years; median duration, 245 months). In all cases, other risk factors for the development of HCC (hepatitis B virus and hepatitis C virus infections, alcohol consumption, and metabolic or autoimmune disorders) were excluded. Three patients had concomitant cirrhosis. The p53 gene was examined by direct sequencing of exons 5-9. RESULTS: Mutations of the p53 gene were found in 11 of 18 HCCs examined. The point mutations detected were comprised of five transversions and five transitions. Five of 11 mutations (codons 175, 245, 248, 273, and 282) occurred at CpG sites. Histopathologic liver alterations (mild sinusoidal dilatation, [portal] fibrosis, and centrilobular siderosis) in tumor surrounding nonneoplastic liver confirmed exposure to VC. CONCLUSIONS: The results of the current study indicated a relation between VC exposure and the development of HCC. The mutation pattern of p53 with a nearly equal rate of incidence of transitions and transversions and a high rate of incidence of mutations at CpG sites may reflect endogenous mechanisms (e.g., deamination of 5-methylcytosine) rather than exogenous carcinogens.

Aged↗

Laparoscopic abdominoperineal resection: early postoperative results of a prospective study involving 116 patients. The Laparoscopic Colorectal Surgery Study Group.

PURPOSE: Although laparoscopic colorectal surgery is attracting ever more attention, its use for curative treatment of colorectal carcinoma in particular continues to be controversial. The present study was an attempt to analyze the results of the perioperative course, oncologic quality, and preliminary long-term results. METHOD: The data considered here were collected within the framework of a prospective, observational study initiated on August 1, 1995, and involving a total of 18 institutions in Germany and Austria. At the end of three years, the results are now being presented selectively, i.e., focusing only on abdominoperineal resection. RESULTS: A total of 116 patients underwent laparoscopic abdominoperineal resections, 98 (84.5 percent) of which were performed with curative intent. The mean operating time was 226 (confidence interval, 140-365) minutes. Seven patients (6 percent) experienced an intraoperative complication, which in more than one-half of the cases was a vascular injury involving the presacral venous plexus; the conversion rate was 3.4 percent. Postoperatively, 40 patients developed 97 complications--including those of a very minor nature--giving an overall morbidity rate of 34.4 percent. Reoperation in six patients (5.2 percent) had to be performed for an afterbleed in one-half of the cases and ileus in the other one-half. Postoperative mortality was a low 1.7 percent. In most of the curative resections, an oncologically radical operation with high transection of the inferior mesenteric artery and a complete dissection of the pelvis down to the floor was performed. The median number of lymph nodes investigated was 11.5, and there was wide fluctuation in the numbers among the individual institutions. Tumor cell dissemination occurred intraoperatively in five patients. In the meantime, 79 patients (81 percent) underwent at least one follow-up examination, the mean follow-up period being 491 days. Seven patients developed a local recurrence, and a further six patients developed distant metastases. For recurrence-free survival rate, the Kaplan-Meier estimation calculated a probability of 71 percent. CONCLUSION: Not all of the reservations about laparoscopic abdominoperineal resection, in particular with regard to resection with curative intent, have yet been eliminated. The present study does, however, show that a laparoscopic approach can in principle meet oncologic requirements of radicality and, with regard to the postoperative course, is associated with considerable benefits to the patient.

Abdomen↗

Laparoscopic surgery for the cure of colorectal cancer: results of a German five-center study.

PURPOSE: The aim of this study was to assess the feasibility and safety of laparoscopic surgery for the cure of colorectal cancer with emphasis on oncologic follow-up in particular. METHODS: A study was performed of patients with colorectal cancer treated by laparoscopy in five German centers between May 1991 and September 1997. Surgical and pathologic data were recorded in an anonymous registry database and analyzed by type of resection. Standard procedures were sigmoid or left colectomy, anterior resection, abdominoperineal resection, and right hemicolectomy. Follow-up information included incidence of local, distant, and port site recurrence and cancer-related death. RESULTS: A total of 399 patients (212 females) with a mean age of 66.6 years underwent laparoscopic curative resections (sigmoid resection, 89; left colectomy, 11; anterior resection, 157; abdominoperineal resection, 102; right hemicolectomy, 40). Conversion was necessary in 6.3 percent (n = 25). Complications requiring reoperation occurred in 9 percent (n = 35). Complications that were treated conservatively occurred in 27.6 percent (n = 110). Thirty-day mortality was 1.8 percent (n = 7). First bowel movements resumed on the third postoperative day; patients did not use analgesics after a mean of five days. Mean postoperative hospitalization was two weeks. According to International Union Against Cancer classification, 147 patients had Stage I cancer, 35 had Stage II cancer, and 217 underwent curative resection for Stage III cancer. Mean number of lymph nodes resected was 12.1. At a mean follow-up of 30 months, one port site recurrence was documented. No local recurrence was observed after curative resection of Stage I colorectal cancer. Of 399 patients, local recurrence occurred in 6 patients (Stage II, 2; Stage III, 4), and distant metastases were documented in 25 patients (Stage I, 3; Stage II, 3; Stage III, 19). The highest incidence of cancer-related death occurred after abdominoperineal resection (4.9 percent). CONCLUSION: To assess the role of laparoscopic colorectal surgery for the cure of cancer objectively, prospective randomized trials are necessary.

Abdomen↗

Laparoscopic management of traumatic ruptures of the diaphragm.

INTRODUCTION: As a result of the relatively high frequency of high-speed accidents, diaphragmatic rupture is a diagnosis that is increasingly being established. Not all of these, usually multi-traumatized, patients are diagnosed as having diaphragmatic rupture immediately following the traumatic event--rather, an appreciable number of these injuries are not detected until some time later--often after a considerable delay. Most of the cases involve rupture of the left diaphragm, with most defects occurring in the region of the central tendon. METHODS: During the course of the second half of the year 1998, we operated on three patients with left diaphragmatic rupture. Two of these patients were treated immediately following traumatization, while the third case was a 10-year-old rupture originally misdiagnosed as a para-esophageal hernia. In all three cases, we were able to reduce the hernia and close the diaphragmatic defect laparoscopically. In the case of the two patients with a fresh rupture, the post-operative course was unremarkable, while in the patient with the missed rupture, a serous pleural effusion requiring drainage occurred on the left side. CONCLUSION: Overall, it would appear that in the case of an acute traumatic diaphragmatic rupture in particular, laparoscopic management, with its low level of traumatization and excellent access, offers a favorable alternative to conventional surgery. A point to be considered, however, is the fact that probably not every hospital will have the facilities for laparoscopic management available on a 24-h basis. In the case of longstanding ruptures, reduction of herniated bowel and treatment of the rupture will make considerable demands on the surgeon.

Hernia, Diaphragmatic, Traumatic↗

Feasibility of therapeutic pneumoperitoneum in a large animal model using a microvaporisator.

BACKGROUND: Multimodal therapy is used increasingly in advanced gastrointestinal tumors. Potential benefits of using an intraoperative adjuvant therapy during laparoscopy for cancer have been documented in animal studies. The aim of this study was to develop a device that could deliver such an intraoperative drug therapy. METHODS: We developed a micropump suitable for minimally invasive surgery procedures that allowed microdroplets of therapeutic substance to be distributed into the pneumoperitoneum (CO2), creating a "therapeutic pneumoperitoneum." A closed-loop control system regulates drug delivery according to the gas flow. In vitro, the micropump is able to aerosolize various aqueous and ethanol solutions, including cytostatic and bacteriostatic drugs and adhesion-modulating agents. The size of the microdroplets has been optimized to prevent visual artifacts. RESULTS: The micropump was tested in an animal model (pig). The system was inserted into a 5-mm trocar. After insufflation of a 12-mm CO2 pneumoperitoneum, laparoscopic sigmoid colon resections could be performed with no special difficulties. No fog developed, and no system-related complication was observed. At autopsy, the active principle was distributed to all exposed peritoneal surfaces. CONCLUSIONS: As opposed to conventional peritoneal washing, therapeutic pneumoperitoneum reaches the entire peritoneal surface, allowing an optimal drug distribution. Drug diffusion into the tissues is enhanced by the intraperitoneal pressure. Precise determination of the instantaneous and total drug quantity is possible. Therefore, this drug delivery system has several advantages over conventional irrigation. Its potential domains of application are locoregional cancer therapy, prevention of port-site recurrences, immunomodulation, analgesia, peritonitis, and prevention of postoperative adhesions.

Abdominal Neoplasms↗

Mutations of p53 tumor suppressor gene, apoptosis, and proliferation in intrahepatic cholangiocellular carcinoma of the liver.

This study was performed to examine the correlation between mutations of the p53 tumor suppressor gene, the occurrence of apoptosis, and proliferation in cholangiocellular carcinoma of the liver. The results obtained were compared with pathohistological stage (according to UICC) and grade and with disease related survival rate. In 41 curatively (R0-) resected intrahepatic cholangiocellular carcinomas, the status of the p53 gene was determined by direct sequencing of exons 4-9 and immunohistochemically. Apoptosis was assessed using the in situ end labeling (ISEL) technique in combination with morphological criteria. Proliferation was analyzed by immunohistochemistry of MIB-1 (Ki-67), Proliferating cell nuclear antigen (PCNA), and silver-stained nucleolar organizer regions (AgNOR). The results obtained were compared with pathohistological stage (according to UICC), grade, several other histopathological factors, and survival rate. Mutations of p53 were detected in 15/41 carcinomas examined (37%). The most common change was a G-->C and C-->T transition, changing the hot spot amino acid determined by exons 4-8. Of these 15 tumors, 14 were also p53-positive by immunohistochemistry. In each carcinoma examined, we could demonstrate MIB-1, PCNA, and AgNOR dots and also apoptotic cells in variable proportions. The proliferation markers showed a significant correlation among themselves. In univariate survival analysis, the extent of the primary tumor, lymph node status, grade, and p53 were significant factors influencing patient survival. Performing multivariate Cox regression survival analysis, however, only the extent of primary tumor and lymph node status had an independent prognostic impact. Apoptosis was not related to patient prognosis or to other parameters examined. In conclusion, these results indicated that p53 could serve as an additional prognostic parameter that could provide auxiliary information for patient outcome. However, tumor stage and lymph node involvement were the strongest prognostic factors. We failed to establish apoptosis or other pathological parameters as factors predicting the prognosis of patients with cholangiocellular carcinoma.

Apoptosis↗

Description of an intraperitoneal tumour xenograft survival model in the pig.

AIMS: Experimental animal studies are necessary if the results of minimally invasive oncological surgery are to be improved. In particular the influence of surgical technique on tumour implantation needs further assessment. Small animals such as rodents are inappropriate for such laparoscopic surgical studies. There is a requirement for another animal tumour model with animals greater in size. METHODS: Accordingly we developed an intraperitoneal tumour xenograft survival model using the domesticated pig. After creating a 12 mmHg pneumoperitoneum, 10(7)human HeLa cells were injected into the peritoneal cavity of nine non-syngeneic animals to induce tumour xenograft. Resection of the sigmoid colon using four trocars and a transanal double-stapling technique was performed. The mean operating time was 69 min. No signs of post-operative pain symptoms were observed, and all the animals survived the procedure and gained weight. After 4 weeks, the animals were sacrified and all incision sites and anastomoses were excised. RESULTS: Immunohistochemical staining with antihuman pancytokeratin antibodies confirmed tumour implants in 25 out of 36 port-sites (63.8%). No peritoneal carcinosis nor tumour implants at anastomosis sites were observed. CONCLUSION: This intraperitoneal xenograft tumour model in the pig can be applied in survival studies to check the quality of surgical techniques and its influence on tumour implantation following laparoscopy for cancer.

Animals↗

Frequency of p16(INK4A) alterations and K-ras mutations in intrahepatic cholangiocarcinoma of the liver.

BACKGROUND: Inactivation of the tumour suppressor gene p16 (CDKN2/MTS-1/INK4A) and K-ras mutations are among the most frequent genetic alterations in human malignancies. AIMS: To investigate the tumour suppressor gene p16 and its possible association with K-ras mutations in intrahepatic cholangiocarcinomas of the liver. METHODS: The status of p16 was evaluated in 41 cholangiocarcinomas by methylation specific polymerase chain reaction, microsatellite analysis, DNA sequencing, and immunohistochemical staining. K-ras mutations were determined by direct DNA sequencing analyses after microdissection. The results obtained were correlated with histopathological variables and patient survival. RESULTS: Hypermethylation of the 5' CpG island of the p16 gene was found in 34 of 41 (83%) carcinomas. Homozygous deletion at the p16 region was present in two (5%), and loss of heterozygosity (LOH) in eight cases (20%). We failed to detect p16 gene missense mutations. K-ras mutations were found in 22 of 41 (54%) cholangiocarcinomas and in two cases of tumour surrounding non-neoplastic liver tissue. All 22 cancers with K-ras mutations also exhibited methylated p16. We failed to observe a correlation between K-ras or p16 status and histopathological factors or prognosis of patients. CONCLUSION: These data suggest that inactivation of the p16 gene is a frequent event in cholangiocarcinoma. The most common somatic alteration is promotor methylation of the p16 gene which is closely associated with K-ras mutations. We failed to establish p16 or K-ras status as independent prognostic factors in these tumours.

Bile Duct Neoplasms↗

[Anatomy of the liver].

Over the past decades, great progress has been made in surgery on the liver. Technical achievements and the strict application of anatomical knowledge to surgical practice have added a new dimension to the field of liver surgery. In some cases, new facts about the anatomy of the liver needed considerable time before being implemented. Surgery of liver metastases, primary tumours of the liver and not least liver transplantation have focussed the interest of visceral surgeons more and more on this organ. Segment-orientated liver anatomy, a knowledge and consideration of vascular structures, and the observance of anatomical landmarks are the prerequisites for successful surgery on the liver.

Bile Ducts, Intrahepatic↗

[Prognostic significance of proliferation markers in hepatocellular carcinoma (HCC)].

BACKGROUND: The prognosis of patients with curatively resectable hepatocellular carcinoma depends mainly on anatomic extent of the tumour and on the general condition of the patient. Given the growing evidence that proliferation indices may be of prognostic significance in hepatocellular carcinomas, identification and quantitation of proliferative capacity may be of prognostic importance. METHODS: We have compared four different methods to assess proliferation in a series of 193 curatively (R0-) resected hepatocellular carcinomas: Mitotic count, immunohistochemical assessment of the MIB-1- (Ki-67-), Antigen Proliferating Cell Nuclear Antigen (PCNA) and silverstained nucleolar organiser regions (AgNOR). The results obtained were compared with pathohistological stage (according to UICC), Edmondson Grade and with survival rate. RESULTS: In each carcinoma, we could demonstrate mitotic figures, MIB-1, PCNA and AgNOR dots in variable proportions. Significant statistical correlations were seen between Mitotic Index, the rate of nuclear positivity for MIB-1 and PCNA and the number of AgNOR dots. In univariate survival analysis tumour stage and Edmondson Grade, Mitotic Index, MIB-1 and PCNA Index and mean AgNOR-number were significant patients' survival influencing factors. Performing multivariate Cox survival analysis, Mitotic Index, concomitant cirrhosis, Edmondson Grade and patient age were the only significant independent prognostic factors. CONCLUSION: These results indicated that Mitotic Index is an additional prognostic parameter which could provide auxiliary information for patients' outcome.

Adult↗

[Malignant hepatobiliary tumors. Surgical requirements concerning preoperative diagnosis].

Depending on the results of the diagnostic work-up of a hepatobiliary tumour, the further therapeutic strategy may vary appreciably. The data needed to decide whether a malignant growth is resectable or not include information on the nature, size and location of the tumour, the number of lesions presenting, extrahepatic tumour-related manifestations, the individual hepatic anatomy and additional liver diseases. Despite the recent technical advances, the various diagnostic imaging procedures all have their limitations; used in combination, however, they can provide adequate information in 90-100% of the cases. The most important of these procedures are ultrasonography and spiral CT--including the use of contrast agents--and in some cases also MRT. Thanks to the topographic information they provide, the three-dimensional methods are gaining popularity. While angiography, scintigraphy and ERCP are useful supplementary methods, they do not suffice for the primary diagnosis. In some cases, intra-operative diagnosis may make necessary a change in the planned therapeutic procedure. The limitations and possibilities of the diagnostic strategy--which in no small part is also codetermined by the patient's prehistory and the experience of the examiner--are discussed.

Adult↗

[Animal experiment study on pros and cons of laparoscopic interventions on the liver].

The safety of laparoscopic liver resections compared to open procedure was to be evaluated in an animal study. Besides it had to be examined, whether onco-surgical principles could be kept sufficiently. Therefore 8 one-year-old pigs underwent laparoscopic liver resections; in 2 pigs left-lateral segmental resections were performed, in 5 left-sided hemi-hepatectomies and in one right-sided hemihepatectomy. It became obvious that a control of the vessels around the v. cava inf., of the left branch of the portal vein and of the suprahepatic veins was not possible with sufficient safety. Extraction of the preparations was a further problem. According to these results laparoscopic hemihepatectomy cannot be recommended for clinical routine. Further indications for a laparoscopic operation like deroofing of liver cysts, wedge-resections or treatment of superficial liver injuries are to be accepted.

Animals↗