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A Sendler

Publications and source records attributed to A Sendler.

At least 19 recordsLinked to original sources
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↗
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

Esophageal cancer: patient evaluation and pre-treatment staging.

Improvements in the overall survival of patients with esophageal cancer can in the future only be achieved by tailored therapeutic strategies which are based on the individual histologic tumor type, tumor location, tumor stage at the time of presentation, consideration of established prognostic factors and the physiologic status of the patient. The major aim of every diagnostic strategy is to assess whether a complete macroscopic and microscopic tumor resection (i.e. an R0 resection) can be achieved by primary surgical approach with a high degree of likelihood. This requires histologic classification of the tumor type (squamous cell cancer or adenocarcinoma), the exclusion of distant solid organ metastases, localization of the primary tumor in relation to the tracheobronchial tree, and determination of the T-category and the surrounding structures of the primary tumor. This is currently achieved by a combination of contrast radiography, endoscopy with biopsy, endoscopic ultrasonography and CT scan. PET scanning will in the future be more widely used in esophageal cancer staging because it appears to be superior to current imaging modalities in the exclusion of distant solid organ and lymph node metastases and allows early assessment of response of the primary tumor to neoadjuvant treatment. Systematic risk analysis with a dedicated composite scoring system is essential to assess the physiologic status of the patient and reduce postoperative mortality. Only hospitals with a sufficient case load of esophageal cancer patients ('hospital volume') and a dedicated interest in the management of this disease ('centers of excellence') can provide the required expertise and standards for patient evaluation and tailored therapy.

Adenocarcinoma↗
PubMed2001

[Response evaluation--pathway for accurate indications development].

Only patients, which respond to neoadjuvant therapy and in which a subsequent complete resection (R0) is possible, demonstrate a significant survival advantage compared to non-responders. Therefore, a sensitive response evaluation is of high clinical interest. Response evaluation by endoscopy, biopsy, endoluminal ultrasound or by CT scan showed unfavourable and overall nor reliable results. In recent studies, a accurate response prediction employing 18FDG-PET seems to be possible. Following neoadjuvant chemoradiation of esophageal cancer, a sensitive differentiation between responders and non-responders was possible in a retrospective study. In the beginning are investigations, to differentiate already after two weeks of therapy between both groups of patients.

Combined Modality Therapy↗
PubMed2000

Potential and futility of sentinel node detection for gastric cancer.

The technique and scientific background of sentinel node dissection has spread extremely rapidly over the surgical community. Following the addition of this technique to the tools of oncologic surgery for treatment of malignant melanoma and breast cancer, questions arise regarding the use of this method in gastric cancer also. While the lymphatic flow on the surface of the body can be defined easily, the lymphatic drainage of the stomach is much more complicated. Following rotation of the stomach during embryonic development, the lymphatic flow is not directed in a simple fashion. It is questionable whether a specific area of the stomach will drain into one lymph node echelon only. This is one of the essential obstacles for SLND in gastric cancer. Furthermore, skip metastasis seems to be quite common in cancer of the stomach. In gastric cancer, the value and the extent of classical lymph node dissection itself is still under scientific discussion. The rationale, aims, and extent of LA in gastric cancer are addressed. The scientific discussion on whether D1 or an extended lymphadenectomy are appropriate is not finally closed as yet. The possibilities and problems concerning an individualised indication for a selective lymphadenectomy in gastric cancer are discussed.

Humans↗
PubMed2000

[New therapy approaches in tumors of the upper gastrointestinal tract (esophagus, stomach)].

Despite numerous phase-II and phase-III studies investigating neoadjuvant treatment in esophageal and gastric cancer, the value of multimodal therapy in these tumors is not clearly defined yet. One reason are the different study entry criteria and different staging modalities in the investigations published so far. Concerning esophageal cancer, neoadjuvant chemotherapy does not yet have a definite role after several phase-III studies. It may be that this treatment should only be inaugurated in innovative protocols. Furthermore, in esophageal cancer it is proven that chemoradiation is superior to radiation alone in the neoadjuvant setting. Following neoadjuvant chemoradiation, there is a distinct trend in favor of multimodal therapy. In the case of locally advanced squamous cell carcinoma of the esophagus, neoadjuvant chemoradiation offers 30%-60% of the patients the possibility for a complete resection (UICC-R0); however, this is accompanied by increased postoperative morbidity and mortality. In gastric cancer, neoadjuvant chemotherapy is still an experimental approach. Intraperitoneal chemotherapy has failed to show any benefit in Western trials. Clinically related research is concentrating on the problem of distinguishing responder from non-responder at the beginning of the therapy. First results indicate that with molecular markers, response might be predicted before therapy. Using 18-FDG PET, it could be possible that the response can be recognized after only 1 week of treatment, opening the door to early response evaluation. New therapeutics like monoclonal antibodies for adjuvant therapy, which is again under discussion in gastric cancer, are only in phase-I studies.

Combined Modality Therapy↗
PubMed2000

Preoperative evaluation of pancreatic masses with positron emission tomography using 18F-fluorodeoxyglucose: diagnostic limitations.

Identification of pancreatic cancer in patients presenting with an enlarged pancreatic mass is a major diagnostic problem. Positron emission tomography (PET) using the radiolabeled glucose analogue 18F-fluorodeoxyglucose (FDG) has been suggested to provide excellent accuracy for noninvasive determination of suspicious pancreatic masses. We conducted a prospective study to verify these results. Forty-two patients admitted for pancreatic surgery underwent PET scanning. Image analysis was based on visual film evaluation and quantification of regional tracer uptake. PET imaging was visually analyzed by three observers blinded for the results of other diagnostic tests; they qualitatively graded the scans using a five-point scale (I = low to V = high) for the presence and intensity of focal FDG uptake. Diagnosis was proven by histology (n = 38) or follow-up (n = 4). Furthermore, the results of PET were compared with helical computed tomography (CT) and conventional ultrasonography (US), done during the routine diagnostic workup before pancreatic cancer surgery. Regarding only the results with scores of IV and V as positive for representing definite malignancy yielded a sensitivity of 71% and a specificity of 64% for film reading. Quantification of regional tracer uptake contributed no significant diagnostic advantage for differentiation between benign and malignant tumors. Helical CT revealed a sensitivity of 74% and a specificity of 45.5% and abdominal US 56% and 50%, respectively. We concluded that PET imaging provides only fair diagnostic accuracy (69%) for characterizing enlarged pancreatic masses. PET does not allow exclusion of malignant tumors. In doubtful cases, the method must be combined with other imaging modalities, such as helical CT. The results indicate that the number of invasive procedures is not significantly reduced by PET imaging.

Adenocarcinoma↗
PubMed2000

Multidisciplinary approach to esophageal and gastric cancer.

Despite marked advances in surgical therapy for patients with esophageal, esophagogastric, and gastric cancers, the overall prognosis of these patients has not markedly improved during the past decades. Multidisciplinary approaches using adjuvant postoperative and neoadjuvant preoperative therapeutic principles have received increasing attention with regard to the management of these patients. A series of randomized, prospective trials has demonstrated that adjuvant postoperative radiation or chemotherapy does not result in a convincing survival advantage after complete tumor resection in esophageal, esophagogastric junction, or gastric cancer. The available data on the role of neoadjuvant preoperative therapy are not yet conclusive. Although neoadjuvant therapy may reduce the tumor mass in many patients, several randomized, controlled trials have shown that, compared with primary resection, a multimodal approach does not result in a survival benefit in patients with locoregional, that is, potentially resectable, tumors. In contrast, in patients with locally advanced tumors, that is, patients in whom complete tumor removal with primary surgery seems unlikely, neoadjuvant therapy increases the likelihood of complete tumor resection on subsequent surgery, but only patients with objective histopathologic response to preoperative therapy seem to benefit from this approach. Consequently, in the future, improvements in the overall survival of patients with esophageal, esophagogastric junction, or gastric cancer most likely will be achieved only by tailored therapeutic strategies that are based on the individual tumor location, tumor stage, and consideration of established prognostic factors. A clear classification of the underlying tumor entity, a profound knowledge of the prognostic factors applicable, a thorough preoperative staging, and identification of parameters that allow for the prediction of response to preoperative therapy will become essential for the selection of the optimal therapeutic modality for individual patients.

Adenocarcinoma↗
PubMed1999

Surgical resection for cancer of the cardia.

From the pathogenic and therapeutic point of view, adenocarcinomas of the esophagogastric junction (AEG) should be classified into adenocarcinoma of the distal esophagus (Type I), true carcinoma of the cardia (Type II), and subcardial carcinoma (Type III). This classification can be easily performed by summarizing the information available from contrast radiography, endoscopy, and intra-operative findings; it allows comparison of data between various centers and facilitates the choice of surgical therapy. A complete removal of the primary tumor and its lymphatic drainage has to be the primary goal of any surgical approach to adenocarcinoma of the esophagogastric junction. In patients with potentially resectable, true carcinoma of the cardia (AEG Type II), this can be achieved by a total gastrectomy with transhiatal resection of the distal esophagus and en bloc removal of the lymphatic drainage in the lower posterior mediastinum and along the celiac axis and superior border of the pancreas. This approach is associated with lower morbidity and provides equal long-term survival as compared to the more radical transmediastinal or abdominothoracic esophagogastrectomy. Whether a routine splenectomy for lymphadenectomy in the splenic hilus offers a survival benefit in these patients is questionable. In patients with early tumors staged as uT1 on pre-operative endosonography, a limited resection of the proximal stomach, cardia, and distal esophagus with interposition of a pedicled isoperistaltic jejunal segment appears justified since this procedure allows a complete tumor removal with adequate lymphadenctomy and offers excellent functional results. Multimodal therapy with pre-operative polychemotherapy or combined radio-chemotherapy appears to offer a significant survival benefit in patients with locally advanced tumors. With this tailored approach, extensive pre-operative staging becomes mandatory for an adequate selection of the appropriate therapeutic concept.

Adenocarcinoma↗
PubMed1998

Bronchogenic cyst of the esophagus with high tumor marker levels--a case report and review of the literature.

Bronchogenic cysts of the esophagus are rare in comparison with the relatively common bronchogenic cyst of the lung. Only a few cases have been reported in literature since 1930. We report on a case of a 43-old-male with a bronchogenic cyst in the distal esophagus, which was misdiagnosed as a malignant esophageal tumor based on preoperative imaging and high levels of the tumor markers CA 19-9 and CA 125.

Adult↗
PubMed1998

Antibodies TC-12 ("unique") and TH-111 (CD96) characterize T-cell acute lymphoblastic leukemia and a subgroup of acute myeloid leukemia.

To extend the panel of monoclonal antibodies useful for immunophenotyping of acute leukemias, two new reagents, TC-12 and TH-111, were developed. TC-12 was found "unique," and TH-111 was assigned to the recently defined CD96 cluster. Both reagents show little reactivity with blood and bone marrow nucleated cells but define a major (TH-111: 78.3%) or an important (TC-12: 45.6%) subset of T-cell acute lymphoblastic leukemia (ALL). In addition, in acute myeloid leukemia (AML), the expression of TC-12 was found in 64 (20.2%) of 317 and TH-111 in 97 (29.1%) of 333 of these patients. TC-12 positivity in AML was virtually restricted to the Fab subtypes M0, M1, M2, and M6. In the group of immature AML characterized by the coexpression of CD7 as well as CD117 and CD34 positivity, leukemic blasts frequently disclosed the TC-12 and TH-111 antigen. Although the TC-12 antigen could not be determined, TH-111 immunoprecipitated the TACTILE (CD96) antigen and, when expressed, was found to be associated with the transferrin receptor. These reagents may help not only to define and dissect T-cell ALL, but also to characterize a subgroup of immature AML at the divergence of T-cell and myeloid lineage.

Animals↗
PubMed1997

High frequency of simultaneous loss of p16 and p16beta gene expression in squamous cell carcinoma of the esophagus but not in adenocarcinoma of the esophagus or stomach.

Quantitative reverse transcription PCR (RT-PCR) was used to measure gene expressions (relative mRNA levels) of p16 and the alternate transcript pl6beta in esophageal and gastric tumors. p16 gene expression was undetectable in 13 of 25 esophageal squamous cell carcinomas. In 11 of these tumors, pl6beta was simultaneously missing whereas two of the pl6-deficient tumors still expressed p16beta. Among 34 esophageal adenocarcinomas and 11 gastric adenocarcinomas, only one tumor lacked p16 expression and all tumors expressed p16beta. p16 sequences were not detectable by PCR in genomic DNA from tumors lacking both p16 and p16beta mRNA, suggesting that the simultaneous loss of both gene expressions resulted from homozygous genomic deletion of the p16 gene. However, DNA from tumors that lacked p16 mRNA but expressed pl6beta did contain the p16 gene, consistent with loss of p16 expression in these tumors by transcriptional suppression. No point mutations in p16 cDNA were detected among 12 that were sequenced, but one p16 cDNA from a squamous cell carcinoma had a 19-base deletion, possibly indicating a splice-site mutation. Among those tumors that expressed p16 mRNA, the gene expression values of both p16 and pl6beta varied over a wide range. In some cases, p16 expression was detectable but low, suggesting that down-regulation of p16 expression may be used in some cases to achieve the funtional equivalent of gene deletion or transcriptional silencing. These results demonstrate that p16 expression patterns differ based on tumor histology and origin. Homozygous deletion of p16 appears to be common in esophageal squamous cell carcinomas but in adenocarcinomas, both gene deletion and transcriptional silencing of p16 were infrequent.

Adenocarcinoma↗