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J R Siewert

Publications and source records attributed to J R Siewert.

At least 19 recordsLinked to original sources
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↗
PubMed2001

[Esophageal carcinoma: 2-stage operation for preventing mediastinitis in high risk patients].

Strict patient selection, standardization of the surgical technique and advances in peri- and postoperative management have in experienced centers resulted in a decrease in postoperative mortality after esophagectomy and reconstruction to less than 5% in recent years. The previously common and potentially lethal pulmonary and cardiac complications have lost their impact on outcome. Today, septic complications, which usually arise from the reconstruction phase, constitute the major morbidity and mortality factors in the surgical therapy of esophageal cancer. These complications pose a particular problem for patients with compromised organ function and patients after neoadjuvant combined radiochemotherapy. In these situations a surgical safety concept with a two-stage procedure, i.e., delay of reconstruction after resection for 8-10 days, can markedly reduce the otherwise substantial postoperative mortality. A two-stage procedure thus offers patients a chance of a potentially curative surgical therapy who would otherwise be excluded from resection.

Combined Modality Therapy↗
PubMed2001

Achalasia and esophageal cancer: incidence, prevalence, and prognosis.

Reported incidence rates of carcinoma in patients with achalasia and the prevalence of achalasia in patients with esophageal cancer vary widely in the literature. The prognosis of an "achalasia-carcinoma" is generally considered poor, although systematic studies assessing the incidence, prevalence, and prognosis of patients with "achalasia-carcinoma" are scant. We investigated the incidence of esophageal cancer in a large series of patients with known achalasia, assessed the prevalence of achalasia in patients presenting with esophageal cancer, and evaluated the prognosis of these patients compared to that of patients with esophageal cancer without achalasia. Between 1982 and 1998 a total of 124 patients with primary achalasia were treated and followed at our department. During the same time period 1366 patients presented with esophageal cancer (879 esophageal squamous cell carcinomas, 487 adenocarcinomas). Of the 124 patients with primary achalasia, 4 developed a carcinoma during a mean follow-up of 5.6 years (i.e., an incidence of one carcinoma per 173.6 patient-years of follow-up). Altogether, 13 of 879 patients (1.5%) presenting with esophageal squamous cell carcinoma and 1 of 487 patients (0.2%), presenting with esophageal adenocarcinoma had a history of primary achalasia. Seven patients with achalasia-carcinoma (50%) had early-stage disease (stage I, IIA, or IIB). There was no difference in the prognosis of patients with resected achalasia-carcinoma versus those with esophageal carcinoma but no achalasia. Thus in our population of patients with long-standing achalasia the risk for developing an esophageal cancer was increased about 140-fold over that of the general population. With liberal use of surveillance, carcinoma could often be detected at an early stage in these patients, with a prognosis that was not worse than that of patients with squamous cell esophageal cancer but no achalasia.

Adolescent↗
PubMed2001

Proliferation kinetics and prognosis in gastric cancer after resection.

The influence of proliferation and proliferation kinetics on prognosis in gastric cancer after complete resection are controversial. In a prospective study we investigated the tumour specimens of 111 patients after resection of gastric cancer, who received 200 mg intravenous (i.v.) bromodeoxyuridine (BrdU) pre-operatively. The following biological parameters were analysed in the tumour tissue using flow-cytometry: DNA ploidy, proportion of S-phase cells, BrdU labelling index (LI), DNA synthesis time (T(s)), potential tumour doubling time (T(pot)), proliferating cell nuclear antigen (PCNA) and Ki-67 LI. The median follow-up time was 40 months (range 19-62 months). Besides the established pathohistological prognostic factors, univariate analysis revealed a prognostic influence on survival for BrdU LI, T(pot) and the proportion of S-phase cells. By multivariate Cox analysis of the completely resected cases, only tumour stage and T(pot) had a significant, independent influence on survival. By classification and regression trees (CART) analysis, resection status, tumour stage and T(pot) defined risk groups with significantly different outcomes. A short T(pot) was a predictor of better survival in stage I, II and IIIA tumours. Ploidy and the other investigated proliferation-related parameters failed to demonstrate any influence on prognosis after resection of gastric cancer.

Adenocarcinoma↗
PubMed2001

[Therapy of esophageal diverticula].

Diverticula of the esophagus can be divided into two categories. Pulsion diverticula result from an increased pressure gradient through the upper esophageal sphincter resulting in herniation of the mucosa through a weak point of the muscle layer. There are two types: hypopharynx (Zenker) diverticulum and epiphrenic diverticulum. Traction diverticula result from inflammatory reactions in neighboring lymph nodes or as a result of embryonic malformation and are composed of all layers of the esophageal wall. The presence of a Zenker diverticulum in a symptomatic patient represents always an indication for surgical therapy. A successful procedure contains a diverticulectomy combined with cervical myotomy. For the treatment of epiphrenic diverticula the underlying motility disorder, determined by preoperative manometry, plays a crucial role in the length of the myotomy. In order to prevent postoperative reflux a partial fundoplication should be added. Independent of location or size surgical therapy of diverticula of the esophagus has a success rate of more than 90 percent.

Diagnosis, Differential↗
PubMed2001

Her-2/neu gene amplification, elevated mRNA expression, and protein overexpression in the metaplasia-dysplasia-adenocarcinoma sequence of Barrett's esophagus.

SUMMARY: The importance of alterations of the Her-2/neu oncogene in the tumorigenesis of Barrett's adenocarcinoma (BCA) is discussed controversially. In the present study, we evaluated for the first time the Her-2/neu status in the metaplasia-dysplasia-adenocarcinoma sequence of BCA simultaneously at the DNA, mRNA, and protein level using resection specimens of 25 patients. The locus-specific Her-2/neu gene status was quantified by performing fluorescence in situ hybridization, and information about the ploidy status of chromosome 17 was obtained. Tissue sections from the same areas were used for quantitative RT-PCR (TaqMan RT-PCR) of laser-microdissected tumor cells and for immunohistochemistry to quantify Her-2/neu mRNA and oncoprotein expression. Her-2/neu gene amplification was observed in 35% of BCA, and all of these samples showed strong overexpression of both mRNA and oncoprotein. A polysomy 17 without Her-2/neu gene amplification was observed in 52% of BCA, showing a normal or moderately elevated mRNA expression and no or weak immunopositivity. From 13 areas of high-grade dysplasia (HGD) we found four to be amplified for the Her-2/neu locus, whereas five showed a polysomy 17. All four samples of HGD areas with Her-2/neu gene amplification displayed mRNA and strong oncoprotein overexpression; however, lower mRNA levels were seen than in the amplified BCA areas. None of the samples with low-grade dysplasia (LGD) showed a locus-specific Her-2/neu amplification, but polysomy 17 was present in four of eight cases. No changes were detected in BCA-associated intestinal metaplasia and squamous epithelium. In summary, only a locus-specific Her-2/neu gene amplification was associated with strong mRNA overexpression and strong membranous Her-2/neu immunostaining in BCA and HGD. A chromosome 17 polysomy, as found in the majority of BCA, led to no or weak mRNA overexpression and no or weak immunopositivity. In the metaplasia-dysplasia-adenocarcinoma sequence, a chromosome 17 polysomy without Her-2/neu gene amplification was already present in LGD. This may be a result of an early polyploidization, preceding the later genetic events, such as Her-2/neu gene amplification in HGD and BCA.

Adenocarcinoma↗
PubMed2001

Neoadjuvant therapy of esophageal squamous cell carcinoma: response evaluation by positron emission tomography.

OBJECTIVE: To evaluate the use of positron emission tomography using [(18)F]-fluorodeoxyglucose (FDG-PET) to assess the response to neoadjuvant radiotherapy and chemotherapy in patients with locally advanced esophageal cancer. SUMMARY BACKGROUND DATA: Imaging modalities, including endoscopy, endoscopic ultrasound, computed tomography, and magnetic resonance imaging, currently used to evaluate response to neoadjuvant treatment in esophageal cancer do not reliably differentiate between responders and nonresponders. METHODS: Twenty-seven patients with histopathologically proven squamous cell carcinoma of the esophagus, located at or above the tracheal bifurcation, underwent neoadjuvant therapy consisting of external-beam radiotherapy and 5-fluorouracil as a continuous infusion. FDG-PET was performed before and 3 weeks after the end of radiotherapy and chemotherapy (before surgery). Quantitative measurements of tumor FDG uptake were correlated with histopathologic response and patient survival. RESULTS: After neoadjuvant therapy, 24 patients underwent surgery. Histopathologic evaluation revealed less than 10% viable tumor cells in 13 patients (responders) and more than 10% viable tumor cells in 11 patients (nonresponders). In responders, FDG uptake decreased by 72% +/- 11%; in nonresponders, it decreased by only 42% +/- 22%. At a threshold of 52% decrease of FDG uptake compared with baseline, sensitivity to detect response was 100%, with a corresponding specificity of 55%. The positive and negative predictive values were 72% and 100%. Nonresponders to PET scanning had a significantly worse survival after resection than responders. CONCLUSION: FDG-PET is a valuable tool for the noninvasive assessment of histopathologic tumor response after neoadjuvant radiotherapy and chemotherapy.

Adult↗
PubMed2001

Histologic tumor type is an independent prognostic parameter in esophageal cancer: lessons from more than 1,000 consecutive resections at a single center in the Western world.

OBJECTIVE: To analyze the changing pattern in tumor type and postoperative deaths at a national referral center for esophageal cancer in the Western world and to assess prognostic factors for long-term survival after resection. SUMMARY BACKGROUND DATA: During the past two decades, the epidemiology and treatment strategies of esophageal cancer have changed markedly in the Western world. The influence of these factors on postoperative deaths and long-term prognosis has not been adequately evaluated. METHODS: Between 1982 and 2000, 1,059 patients with primary esophageal squamous cell cancer or adenocarcinoma had resection with curative intention at a single center. Patient and tumor characteristics and details of the surgical procedure and outcome were documented during this period. Follow-up was available for 95.8% of the patients. Changing patterns in tumor type and postoperative deaths were analyzed. Prognostic factors for long-term survival were assessed by multivariate analysis. RESULTS: The prevalence of adenocarcinoma in patients with resected esophageal cancer increased markedly during the study period. The postoperative death rate decreased from about 10% before 1990 to less than 2% since 1994, coinciding with the introduction of a procedure-specific composite risk score and exclusion of high-risk patients from surgical resection. In addition to the well-established prognostic parameters, tumor cell type "adenocarcinoma" was identified as a favorable independent predictor of long-term survival after resection. The independent prognostic effect of tumor cell type persisted in the subgroups of patients with primary resection and patients with primary resection and R0 category. CONCLUSION: Esophagectomy for esophageal cancer has become a safe procedure in experienced hands. Esophageal adenocarcinoma has a better long-term prognosis after resection than squamous cell carcinoma.

Adenocarcinoma↗
PubMed2001

Extensive sampling improves preoperative bronchoscopic assessment of airway invasion by supracarinal esophageal cancer: a prospective study in 166 patients.

BACKGROUND: The utility of fiberoptic bronchoscopy in the preoperative assessment of patients with esophageal cancer has not been thoroughly investigated. More accurate staging could improve the design of clinical trials and avoid inappropriate surgical decisions in individual patients. STUDY OBJECTIVE: To evaluate the utility of bronchoscopy in the preoperative assessment of airway invasion by supracarinal esophageal cancer. DESIGN: We prospectively analyzed 220 bronchoscopies in 166 consecutive patients with supracarinal esophageal cancer and correlated the findings with operative results and survival. RESULTS: In 126 bronchoscopies (57.3%), no abnormal findings could be seen in the airways. Compared with histologic and cytologic results, the normal macroscopic appearance of the airways had a negative predictive value of 94.4%, but the positive predictive value of all macroscopic abnormalities for the diagnosis of airway invasion was low, particularly after radiation therapy. Endoluminal tumor mass, protrusion of the posterior tracheal wall, and signs of mucosal invasion were visible in 5.9%, 28.6%, and 4.1% of the bronchoscopies, respectively. However, in only 8.6% of the 220 bronchoscopies, cancer invasion was proved by biopsy or cytology. Bronchoscopy with biopsies and brush and washing cytology examinations was the sole decisive staging procedure, enabling the exclusion from surgery because of airway invasion in 18.1% of otherwise potentially operable patients, with an overall accuracy of 93.3% (95% confidence interval, 86.7 to 97.3%). The results of bronchoscopy were falsely negative in six patients, who all underwent surgery after neoadjuvant therapy. CONCLUSIONS: Fiberoptic bronchoscopy with systematic multiple biopsies and brush and washing cytology examinations is an accurate procedure in evaluating the possible invasion of supracarinal esophageal cancer into the airways. Macroscopic findings alone are not reliable; errors in sole bronchoscopic inspection would have resulted in operations that would be unlikely to help the patients or would have inappropriately excluded patients from surgery.

Adult↗