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J R Siewert

Publications and source records attributed to J R Siewert.

At least 73 records · Page 4Linked to original sources
PubMed2002

[Quality management and experiences with the "cancer center"].

BACKGROUND: The goal of quality management in oncology is to achieve the best possible therapeutic outcome. Improved diagnostic methods, more sophisticated therapies in various fields of specialisation and the increased implementation of multimodal therapies have led to considerable advances in the treatment of certain tumors in recent years. However, these advances depend on an interdisciplinary approach necessitating an increased division of labour. These in turn, because of the more complex organizational requirements within hospitals, make greater demands on quality management. METHODS: In October 1999 first steps were taken in the Klinikum rechts der Isar der TU München to organisationally integrate the various institutions involved in the treatment of patients with gastro-intestinal tumors. All the oncologic competence available was bundled in a Cancer Center thus creating the structural prerequisites for interdisciplinary quality management. A daily multidisciplinary Tumor Board, a computer-supported interdisciplinary information and communications system, an interdisciplinary Disease Management Team, an outpatients department and a study centre were all called into life. RESULTS: By the time the outpatients department went into service in November 2001 all the other structural innovations underlying interdisciplinary quality management had already been implemented. Since October 1999 2438 patients had been presented to the Tumor Board, 74% of them with primarily curative intent. CONCLUSIONS: The disease-oriented structure of the Cancer Center has proved worthwhile. The impact of the structure on the quality of processes and results, however, has yet to be evaluated.

Ambulatory Care↗
PubMed2002

Preoperative chemotherapy unmasks underlying Barrett's mucosa in patients with adenocarcinoma of the distal esophagus.

BACKGROUND: Intestinal metaplasia of the distal esophagus frequently cannot be detected in patients with esophageal adenocarcinoma. It has therefore been questioned whether Barrett's esophagus is the primary precursor lesion of such lesions. We hypothesized that the underlying Barrett's mucosa may be masked by tumor overgrowth in the majority of these patients. METHODS: The pretherapeutic endoscopy and biopsy records of 79 patients with locally advanced esophageal adenocarcinoma who had undergone preoperative chemotherapy were reviewed and compared to findings on restaging endoscopy/biopsy and subsequent resection and histopathologic analysis of the resected specimen. RESULTS: Pretherapeutic endoscopy and biopsy showed associated Barrett's esophagus in 59/79 patients, whereas there was no evidence of associated intestinal metaplasia in 20/79 patients on extensive biopsies. Following neoadjuvant chemotherapy, Barrett's mucosa was unmasked and later documented by biopsy or histopathologic assessment of the resected specimen in 18 of the latter 20 patients. This resulted in an overall association of Barrett's mucosa with adenocarcinoma in the distal esophagus of 97.4% CONCLUSION: Underlying Barrett's mucosa is frequently masked by tumor overgrowth in patients with locally advanced adenocarcinoma of the distal esophagus.

Adenocarcinoma↗
PubMed2002

[Extent of resection in surgery of stomach carcinoma].

The extraluminal extent of resection in cases of advanced gastric cancer is controversial. If, however, following meticulous staging--including the detection of free abdominal tumor cells--complete resection seems possible, then multivisceral resection is justified. If complete resection is achieved, the prognosis of these patients can be improved. Left pancreatic resection should be performed only if the tumor invades the pancreas directly. Splenectomy is indicated if the tumor invades the organ directly or if there are locally advanced tumors of the proximal third of the stomach and tumors of the esophageal-gastric junction. However, it has to be kept in mind that splenectomy is an independent negative prognostic factor. The extent of lymphadenectomy (LA) in gastric cancer is still under discussion. According to the 10-year results of the Dutch Gastric Cancer Study, there might be subgroups which have a survival benefit after extended (D2) LA. These include, as the German Gastric Cancer Study corroborated, patients with very early stage II and stage IIIa lymph node metastases. As neither of these stages can at present be diagnosed before or during surgery, D2 lymphadenectomy should be the standard procedure for all patients with gastric cancer. Recent studies have shown that it might be possible with the help of the Sentinel Node Technique to individualize lymphadenectomy in locally gastric cancer as well. The beneficial effects of adjuvant chemoradiation in gastric cancer do not mean, however, that the extent of resection may be reduced. Adjuvant chemoradiation following complete resection and D2 lymphadenectomy should still not be regarded as standard therapy.

Gastrectomy↗
PubMed2002

[Clinic communication and disease-oriented centers].

German hospitals and surgical clinics/departments are facing far-reaching changes. One triggering factor is the imminent reorganization of hospital financing to a system of compensation, which is universally based on diagnosis-related groups (DRGs) and entails a market-economy orientation in the hospital sector. Digital technologies, which facilitate making the necessary adjustments to clinic structures to meet forthcoming challenges, represent another element. The "digital transformation" of the hospital of the future takes place on three levels. The restructuring of the surgical realm runs rather a traditional course by increasing use of information technology, mostly to optimize documentation and existing procedures or to reduce costs. The second sphere reaches substantially further, encompassing reorganization of disease-oriented cooperation between the different medical specialties and enabling the establishment of suitably structured disease-oriented medical centers. This is followed by the third phase, which involves networking clinics or medical centers with private practitioners, aftercare and rehabilitation services, and other disease-oriented care providers.

Computer Communication Networks↗
PubMed2002

Fulminate intracardiac thrombosis associated with Budd-Chiari-syndrome and inferior vena cava thrombosis.

The most common cause of edema of the legs and dyspnea is congestive heart failure. Further differential diagnosis such as renal or hepatic failure have to be considered. We report the case of a previous healthy 65-year-old woman who developed dyspnea and massive edema of the legs followed by acute hepatic and renal failure. Imaging studies showed a thrombosis of the inferior vena cava (IVC) caused by a tumor between the right kidney and the IVC. Histological examination revealed a leiomyosarcoma of the IVC. Hepatic failure due to venous outflow obstruction (Budd-Chiari syndrome, BCS) was diagnosed. Coagulation profile showed a complex disorder due to acute hepatic failure. Factor V Leiden and prothrombin gene mutation G20210A could be excluded. The thrombosis extended from the femoral veins up to the right atrium. After 11 days of anticoagulation with heparin platelet counts decreased by more than 50%. Suspecting a heparin-induced thrombocytopenia the patient was placed on recombinant hirudin (lepirudin) for anticoagulation. Hepatic venogram showed a thrombosis of the hepatic vein orifices but not of the hepatic veins. The tumor and the thrombi were removed surgically. When the cardiopulmonary bypass was terminated new intracardiac thrombi occurred. Despite immediate surgical intervention the patient finally died due to right ventricular failure caused by the fulminate intracardiac thrombosis. In conclusion, thrombosis of the IVC may mimic congestive heart failure and may cause BCS. Neoplasms and coagulation disorders may cause thrombosis of the IVC.

Aged↗
PubMed2002

[Minimal residual disease in gastrointestinal tumors: tumor detection in bone marrow, blood and lymph nodes].

The cure of a tumor patient with gastrointestinal cancer is dependent on the extension of the primary tumor (TNM-classification) and the option of curative resection (R0-resection) at the time of operation. The additional application of multimodal therapy approaches has lead to an improvement of prognosis in different advanced tumor stages. Nevertheless, despite curative tumor resection about 50% of patients with locally advanced gastrointestinal cancer develop recurrent tumor disease or distant metastases and die tumor-related. A possible explanation is the seed of disseminated tumor cells in blood, bone marrow or lymph nodes pre-, intra- or postoperatively, but also during diagnostic procedures. Several studies have shown in the last years that the presence of minimal residual disease (MRD) influences the course of disease and the patient's prognosis after curative tumor resection. Although several groups have reported the prognostic impact of disseminated tumor cells in the different compartments of bone marrow, lymph nodes and blood, the phenomenon of minimal residual disease is not acknowledged as an established prognostic factor and is not integrated into the classification of the UICC. Therefore, no therapeutic consequences were drawn at present from the detection of disseminated tumor cells in patients with gastrointestinal cancer. A possible explanation are missing multi-center-studies, which confirm the results of the several single-center-studies. Standardization of study designs and methodical procedures and the evidence of reproduction are mandatory in order to value and interpret the multitude of studies and the available data in this field. Only these results will allow to decide if the presence and detection of disseminated tumor cells can alter the tumor staging and individualize or possibly minimize further oncological therapy strategies.

Biomarkers, Tumor↗
PubMed2002

[Neoadjuvant therapeutic principles guided by response prediction and evaluation].

Only patients with a clinical and pathohistological response to neoadjuvant therapy have a significantly improved survival. Therefore the identification of predictors for response and procedures for the early identification of nonresponders appear to be mandatory. Preliminary data of biochemical investigations of target enzymes for several cytostatics (e.g. TS, ERCC1) appear to be promising. Early changes of the tumor metabolism in the FDG-PET enable the identification of nonresponders with a negative predictive value of 88-95%. In near future these findings should lead to consequences in the design and realization of clinical studies.

Adenocarcinoma↗
PubMed2002

[Lymph node excision in invasive Barrett carcinoma].

Similar to squamous cell esophageal cancer, the lymph node status constitutes the major prognostic factor after complete tumor resection (R0-resection) in patients with adenocarcinoma of the distal esophagus (the so-called Barrett's cancer). Lymphatic spread in patients with Barrett's cancer, however, appears to follow certain rules. Lymphatic spread is closely correlated to the pT-category of the primary tumor, starts only after infiltration of the submucosa und is initially limited to the regional lymph nodes. Distant lymph node metastases are almost exclusively found in patients with multiple positive regional nodes, skipping of regional lymph nodes is rare. These observations set the stage for tailored lymphadenectomy-strategies based on the, sentinel-lymphadenectomy' concept.

Adenocarcinoma↗
PubMed2001

Lymphatic vessel invasion is an independent prognostic factor in patients with a primary resected tumor with esophageal squamous cell carcinoma.

BACKGROUND: Little data exist about the prognostic role of a lymphatic vessel invasion (LVI) in patients with esophageal carcinoma. The objective of this study was to clarify the presence and prognostic impact of LVI in a large group of patients resected for esophageal squamous cell carcinoma (SCC) at one surgical center. METHODS: Three hundred sixty-six patients, who had a primary resection for SCC, were analyzed by univariate and multivariate analysis. Follow-up was complete for 93.7% patients with a median follow-up of 8.3 years. RESULTS: The total rate of LVI was 39.1% (n = 143). Univariate analysis revealed a significant relation between LVI and different T classifications (P = 0.001), N classifications (P < 0.0001), M classifications (P < 0.0001), International Union Against Cancer (UICC) stages (P < 0.0001), and residual tumor (P < 0.0001). Multivariate analysis of the patients with R0-resected tumors proved LVI as an independent prognostic factor. The 2-, 5- and 10-year survival rates in patients with LVI were 28.5%, 11.1%, and 9.2% compared with 63.4%, 46.6%, and 27%, respectively, without LVI (P < 0.0001). Patients with LVI had a median survival time of 11.4 months compared with 28.6 months without LVI (P < 0.0001). Patients with R0-resected tumors without LVI had a median survival time of 54.1 months compared with 12.1 months in patients with LVI (P < 0.0001) and compared with 11.3 months in patients with R1-resected tumors P < 0.0001). CONCLUSIONS: These data clearly show that LVI is an independent prognostic factor in patients with SCC and confirm the importance of a systematic pathohistologic workup. The prognosis of patients with R0-resected tumors with LVI is equal to patients with an incomplete tumor resection. This supports the inclusion of LVI in the UICC classification system for esophageal carcinoma.

Adult↗
PubMed2001

Prediction of response to preoperative chemotherapy in adenocarcinomas of the esophagogastric junction by metabolic imaging.

PURPOSE: Preoperative chemotherapy in patients with gastroesophageal cancer is hampered by the lack of reliable predictors of tumor response. This study evaluates whether positron emission tomography (PET) using fluorine-18 fluorodeoxyglucose (FDG) may predict response early in the course of therapy. PATIENTS AND METHODS: Forty consecutive patients with locally advanced adenocarcinomas of the esophagogastric junction were studied by FDG-PET at baseline and 14 days after initiation of cisplatin-based polychemotherapy. Clinical response (reduction of tumor length and wall thickness by > 50%) was evaluated after 3 months of therapy using endoscopy and standard imaging techniques. Patients with potentially resectable tumors underwent surgery, and tumor regression was assessed histopathologically. RESULTS: The reduction of tumor FDG uptake (mean +/- 1 SD) after 14 days of therapy was significantly different between responding (-54% +/- 17%) and nonresponding tumors (-15% +/- 21%). Optimal differentiation was achieved by a cutoff value of 35% reduction of initial FDG uptake. Applying this cutoff value as a criterion for a metabolic response predicted clinical response with a sensitivity and specificity of 93% (14 of 15 patients) and 95% (21 of 22), respectively. Histopathologically complete or subtotal tumor regression was achieved in 53% (eight of 15) of the patients with a metabolic response but only in 5% (one of 22) of the patients without a metabolic response. Patients without a metabolic response were also characterized by significantly shorter time to progression/recurrence (P =.01) and shorter overall survival (P =.04). CONCLUSION: PET imaging may differentiate responding and nonresponding tumors early in the course of therapy. By avoiding ineffective and potentially harmful treatment, this may markedly facilitate the use of preoperative therapy, especially in patients with potentially resectable tumors.

Adenocarcinoma↗
PubMed2001

Quality of life before and after laparoscopic Nissen fundoplication.

BACKGROUND: Gastroesophageal reflux disease (GERD) is a common disorder in the Western world. The acute disease can usually be managed by medical therapy. To prevent relapse, many patients require lifelong medication. In these patients, laparoscopic antireflux surgery offers a good alternative. The aim of this study was to evaluate the postoperative results and compare pre- and postoperative quality of life after laparoscopic Nissen fundoplication. METHODS: Clinical investigations, including esophageal manometry, pH monitoring, and endoscopy, and a previously validated Quality of Life Index, were performed before and a median of 41 month after antireflux surgery in 75 patients. RESULTS: After laparoscopic Nissen fundoplication, the percentage of total time with pH <4 decreased from 10.4% to 3.2% on 24-h pH monitoring. The mean pressure of the lower esophageal sphincter improved from 8.1 to 12.3 mmHg. Esophagitis healed in 63 of 66 patients in whom it was present prior to surgery. The overall Quality of Life Index improved significantly from 86 +/- 16 to 116 +/- 16. CONCLUSION: Laparoscopic fundoplication provides effective and durable relief of reflux in patients with GERD. The Quality of Life Index showed significant improvement after surgery.

Adult↗
PubMed2001

Neoadjuvant therapy for patients with locally advanced gastric carcinoma with etoposide, doxorubicin, and cisplatinum. Closing results after 5 years of follow-up.

BACKGROUND: The intent to curatively treat patients with gastric carcinoma is based on complete surgical resection of the primary tumor and its lymphatic drainage. Postoperative adjuvant chemotherapy has failed to show a significant prognostic advantage for these patients. Preoperative chemotherapy, based on promising results in the treatment of patients with disease in primarily unresectable stages, is still being evaluated for those with locally advanced gastric carcinoma. Most published studies still lack adequate staging methods, and long term results of this treatment modality are not known at present. METHODS: In a Phase II study, a series of 42 patients with locally advanced gastric carcinoma (International Union Against Cancer Stages IIIA, IIIB, and IV) initially were staged with endoscopy, with endoscopic ultrasound to establish the clinical tumor classification, with computed tomography scans to rule out tumor infiltration of adjacent organs and to detect distant metastases, and with surgical laparoscopy to exclude occult peritoneal carcinomatosis. Three or four planned cycles of neoadjuvant chemotherapy with etoposide, doxorubicin, and cisplatinum were given prior to total gastrectomy. RESULTS: After a complete follow-up of at least 5 years, there was a median survival of 19.1 months for all patients. Only patients who underwent a complete surgical tumor resection appeared to have a survival benefit, with a median survival of 28.4 months. A superior survival rate was seen in patients who had a major clinical response to chemotherapy, with a median survival of 45 months. CONCLUSIONS: Phase III studies comparing results from patients who undergo neoadjuvant chemotherapy followed by surgery with results from patients who undergo surgery alone should stress the value of adequate pretherapeutic staging and must be accompanied by studies of potential methods for predicting tumor response.

Adolescent↗
PubMed2001

[Reduction of surgical access trauma: reliable advantages].

Minimizing the trauma of surgical access is becoming an essential task in modern surgery. The treatment has to become more comfortable for the patient and financial resources have to be considered. Minimally invasive surgery is one of the attempts to achieve this goal. A comparison of surgical procedures, such as cholecystectomy, fundoplication and sigmoid resection in diverticulitis, which are already routinely performed laparoscopically, should be suitable for evaluating whether minor access surgery is really advantageous. The value of minor access may be quantified by different parameters such as influence upon the immunologic function, lung function, postoperative pain, time of hospitalization, return to work and duration of convalescence, as well as a comparison of the effects upon the quality of life index. The data concerning the effects upon immunology are not unequivocal. All in all, the degree of postoperative inflammation seems to be lower after laparoscopic surgery. There is no doubt that there is far less impairment on lung function, the results are better as far as postoperative pain is concerned, and hospitalization and duration of convalescence are shorter. It is also evident that immediately after the operation the quality of life index is superior, which, however, levels out in the course of time. The advantage of minimally invasive surgery is really apparent only after the mastering of the so-called "learning curve" and in cases of benign malignancies. The role of the minor access approach in oncological surgery is, however, not yet defined.

Humans↗
PubMed2001

[Therapeutic modalities and prognosis].

The individual prognosis of a patient with gastrointestinal cancer is determined by a number of clinical and biological factors. The most relevant prognostic factors are those that can be influenced by the surgeon himself. The completeness of tumor resection, the so-called residual tumor status on the level of the primary tumor in all three dimensions and on the level of the lymphatic drainge is the outstanding factor with an independent influence on the survival of the patient. In addition, the principles of blood-saving preparation with avoidance of blood transfutions, the consideration of no-touch isolation and the complication-free postoperative course have been shown to be independent prognostic factors that can be influenced by the surgeon. There is clear evidence that the hospital volume and the experience of the surgeons, expressed by the number of cases (caseload) in a specific field, has a strong impact on the outcome of a surgical treatment in gastrointestinal cancer patients. To optimize the prognosis of a patient with gastrointestinal cancer one should consider all therapy-related prognostic factors, and therapeutic modalities should be scheduled after a consensus conference (tumor board) of all therapeutic fields involved in the treatment of cancer.

Cancer Care Facilities↗
PubMed2001

[Monitoring of response to neoadjuvant therapy by positron emission tomography (PET)].

Neoadjuvant therapy is frequently hampered by the lack of reliable non-invasive techniques for prediction and assessment of response. Positron emission tomography using the glucose analogue 18F-fluorodeoxyglucose (FDG-PET) provides a unique means of non-invasive assessment of tumor metabolism. Several recent studies have indicated that a reduction of tumor metabolic activity after neoadjuvant therapy is closely correlated with the degree of histopathological tumor regression. The reduction of metabolic activity may also allow one to predict subsequent response early during the course of therapy. Therefore FDG-PET may permit individualized therapy management. However, there is a requirement for larger-scale trials to assess this technique.

Female↗