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T Lehnert

Publications and source records attributed to T Lehnert.

At least 55 records · Page 3Linked to original sources
PubMed2000

Sphincter-saving treatment in epidermoid anal cancer: cooperative analysis of 142 patients in five German university surgical centers.

Five southern German university centers cooperated in comparing the effect of surgical vs. nonsurgical therapy strategies on survival and sphincter preservation in the treatment of anal cancer. A standardized questionnaire was used to evaluate retrospectively (mean follow-up 30 months) treatment strategy and outcome (survival, colostomy rate, colostomy-free survival) in patients treated between 1987 and 1996. Of the 142 patients 65% had squamous cell, 20% basaloid, 6% adeno-, and 1% undifferentiated carcinoma (8% histology not recorded); 9% were classified in UICC stage I, 37% in stage II, 25% in stage III, and 4% in stage IV (25% not recorded). Primary treatment consisted of local excision (10%), excision plus radio- and/or chemotherapy (17%), radiotherapy (20%), radiochemotherapy (28%), or colostomy with or without resection, radiotherapy, and chemotherapy (23%). We observed no difference between these treatment groups in overall (P = 0.43) or colostomy-free survival (P = 0.14, log-rank). Primary colostomy was prevented in 77% of cases and decreased over the years. Mean overall survival (in months) was 42 in stage I, 38 in stage II, and 25 in stage III (P = 0.0013); mean colostomy-free survival was 36 in stage I, 26 in stage II, and 16 in stage III (P = 0.0021, log-rank). Outcome was not significantly related to therapeutic strategy (surgery or radio-chemotherapy. Primary surgical and nonsurgical strategies in treating anal cancer thus produced similar results, although radiochemotherapy is usually recommended for sphincter-endangering anal cancer. Challenges to be met in the future include the prevention of metastasis and long-term preservation of anal sphincter function.

Adenocarcinoma↗
PubMed2000

Curative liver resection for metastatic breast cancer.

AIMS: Hepatic resection is a standard procedure in the treatment of colorectal liver metastases. Liver metastases are frequent in breast cancer, but resectional treatment is rarely possible and few reports have addressed the results of surgical treatment for metastatic breast cancer. The aim of our study was to analyse the outcome of patients with metastatic breast cancer after resection of isolated hepatic secondaries and possibly to identify selection criteria for patients who may benefit from surgery. METHODS: Between 1984 and 1998, 90 patients with a history of breast cancer and suspected liver metastases were referred for surgical evaluation. Fifty-four patients also had extrahepatic disease or metastases from another primary tumour; multiple liver metastases were not amenable to surgical treatment in 20 patients. Five patients were treated by regional chemotherapy via an intra-arterial port catheter; after liver resection two patients were found to have liver metastases from intercurrent colorectal cancer. Thus only nine liver resections for metastatic breast cancer could be performed with curative intent. RESULTS: No patient died post-operatively after liver resection. In the follow-up period, four of the nine patients who were treated with curative intent received systemic chemotherapy. At a median follow-up of 29 months, four patients died from tumour recurrence. Five patients are currently alive. Five-year survival in the resection group was calculated as 51% (Kaplan-Meier estimate). Node-negative primary breast cancer and a long interval between treatment of the primary and liver metastases appeared to be associated with long survival after liver resection. CONCLUSIONS: These observations suggest that careful follow-up and adequate patient selection could offer some patients with isolated liver metastases from breast cancer a chance of long-term survival.

Adult↗
PubMed2000

Two-stage radical gastrectomy for perforated gastric cancer.

INTRODUCTION: Perforation represents a severe complication of gastric cancer. Because it is rare, only few data are available regarding treatment and prognosis. METHODS: Patients with perforated gastric cancer were identified from two prospective registers of gastric cancer and of gastroduodenal ulcer. RESULTS: Between February 1982 and June 1999 23 patients with perforated gastric cancer were treated surgically. This corresponds to only 1.8% of 1273 patients presenting with gastric cancer, but to 14% of 161 patients presenting with gastric perforation during this time period. Overall, post-operative mortality was 13% (3/23). Initially, 21 patients had palliative operations. Two patients had a potentially curative procedure at the emergency operation and one of the two died post-operatively. Another six patients had potentially curative gastrectomy at a second stage and no patient died post-operatively. The 5-year overall survival was estimated at 50% for all eight curatively-treated patients. Median survival of palliatively treated patients was 6 months. CONCLUSIONS: Perforation of the stomach should raise suspicion of malignancy, particularly in elderly patients. At the time of perforation radical gastrectomy with lymphadenectomy is mostly not advised, either because a diagnosis of gastric cancer is not confirmed or because the patient's condition does not allow extended surgery. In this situation it is suggested to consider a two-stage procedure and direct the primary operation at the treatment of perforation and peritonitis. Tumour staging can be completed when the patient has recovered and a radical operation with curative intent can be planned without compromising long-term prognosis. Our observations and a review of the literature confirm that perforation of gastric cancer does not preclude long-term survival per se in a substantial number of patients.

Adult↗
PubMed2000

Chemotherapy with gemcitabine in patients with advanced gallbladder carcinoma.

BACKGROUND: Advanced or metastatic gallbladder carcinoma is regarded not much sensitive to chemotherapy. Standard chemotherapy regimens have not been established up to now. PATIENTS: We report on 5 patients with advanced gallbladder carcinoma who received chemotherapy with gemcitabine. RESULTS: Of these 5 patients, 3 demonstrated a partial remission and stable disease was achieved in another patient. Only one patient had no benefit from treatment with gemcitabine. CONCLUSION: We conclude that gemcitabine may be an effective drug in the palliative treatment of gallbladder cancer, and thus its efficiency warrants evaluation in further studies.

Aged↗
PubMed2000

Clinical value of [18-F]] fluorodeoxyglucose positron emission tomography imaging in soft tissue sarcomas.

OBJECTIVE: To evaluate positron emission tomography (PET) using 2-fluoro-2-deoxy-D-glucose (FDG) for clinical application in soft tissue sarcomas. SUMMARY AND BACKGROUND DATA: FDG PET is a promising noninvasive method for the preoperative assessment of soft tissue sarcomas and may complement radiologic tomography. METHODS: Data from 50 consecutive patients with 59 masses, either suspicious for primary or locally recurrent soft tissue sarcoma, were prospectively gathered. The semiquantitative FDG uptake (standardized uptake values [SUVs]) was calculated in tumor and normal tissue (muscle). Histopathology of surgical specimens and follow-up data were used as control criteria. RESULTS: In primary soft tissue sarcomas, PET displayed a sensitivity of 91% and a specificity of 88%. Local recurrence was detected with a sensitivity of 88% and a specificity of 92%. All intermediate-grade and high-grade soft tissue sarcomas (primary and locally recurrent) were visualized with a precise differentiation from muscle. Fifty percent of the low-grade sarcomas showed an FDG uptake equivalent to muscle (false-negative results in one primary and three recurrent soft tissue sarcomas). Benign soft tissue tumors (e.g., lipoma, leiomyoma, ganglion) did not accumulate FDG. Inflammation resulted in an increased FDG uptake. The semiquantitative FDG uptake (SUVs) correlated with tumor grade but not with size and histologic type. CONCLUSION: High-grade and intermediate-grade soft tissue sarcomas are amenable to PET imaging, whereas low-grade lesions may not be depicted. SUVs for FDG correlate with tumor grade in soft tissue sarcomas. Benign soft tissue tumors are differentiated from higher-grade soft tissue sarcomas. These data show that FDG-PET can complement preoperative radiologic assessment for soft tissue sarcomas and that FDG-PET is a powerful diagnostic tool for detecting high-grade and intermediate-grade local recurrence.

Adolescent↗
PubMed2000

Detection of hematogenic tumor cell dissemination in patients undergoing resection of liver metastases of colorectal cancer.

OBJECTIVE: To determine the extent of pre- and intraoperative hematogenic tumor cell dissemination in patients undergoing liver resection for metastatic colorectal cancer. SUMMARY BACKGROUND DATA: For patients with hepatic metastases of colorectal cancer, liver resection is the only potentially curative therapy. However, 38% to 53% of patients develop extrahepatic tumor recurrence, probably caused by tumor cells disseminated before or during surgery not detected by current staging systems. METHODS: Blood samples harvested before, during, and after surgery from 41 patients and bone marrow samples from 30 patients undergoing resection of liver metastases of colorectal cancer were analyzed for disseminated tumor cells using cytokeratin 20 reverse transcriptase-polymerase chain reaction. RESULTS: Tumor cells were detected in the blood samples of 26 of the 41 patients (63.4%) and in the bone marrow samples of 8 of the 30 patients (26.7%). Tumor cells were detected significantly more often during surgery than before or after surgery. Intraoperative tumor cell dissemination was detected in 41.7% of patients undergoing resection of two or more liver segments but only 14.3% of patients undergoing resection of one liver segment. Compared with resection of primary colorectal cancer, major liver resection carries an increased risk for intraoperative tumor cell dissemination. CONCLUSIONS: Detection of disseminated tumor cells in patients undergoing liver resection for metastases of colorectal cancer using cytokeratin 20 reverse transcriptase-polymerase chain reaction might help to identify patients at high risk for tumor recurrence who may benefit from adjuvant therapy. Major liver resection of metastases leads to frequent intraoperative tumor cell shedding, possibly preventable by alternative surgical strategies.

Adult↗
PubMed2000

Detection of chromosomal imbalances in leiomyosarcoma by comparative genomic hybridization and interphase cytogenetics.

Leiomyosarcomas comprise a group of malignant soft-tissue tumors with smooth-muscle differentiation. In this study, 14 cases of leiomyosarcoma were screened for changes in relative chromosome copy number by comparative genomic hybridization. A high number of imbalances (mean, 16.3; range, 6-26) was detected, with chromosomal gains occurring about twice as much as losses. The most frequent gains were found in 5p15, 8q24, 15q25-->q26, 17p, and Xp (43% to 50%), whereas the most frequent losses were found in 10q and 13q (50% and 78%, respectively). Twenty high-level amplifications affecting 15 different chromosomal subregions were detected in nine different tumors. In three leiomyosarcomas, sequences on chromosome arm 17p were found to be highly amplified, with a minimal overlapping region on subbands 17p12-->p11. We further discovered that the Smith-Magenis syndrome critical region on 17p11.2 is included in the 17p amplicons of two leiomyosarcoma cases. Using probes flanking this genetically unstable region, a mean of 14 and 22 signals per nucleus, respectively, was detected in both leiomyosarcomas by fluorescence in situ hybridization. In conclusion, this analysis identifies a number of characteristic chromosomal imbalances in leiomyosarcomas and provides evidence for the localization of potential oncogenes and tumor suppressor genes active in leiomyosarcoma genomes.

Adult↗
PubMed2000

Molecular profiling of sporadic colorectal tumors by microsatellite analysis.

To investigate the prognostic value of multiple genetic alterations, individual molecular tumor profiles were established in 79 sporadic colorectal carcinomas (41 stage II and 38 stage III). Tumors were analyzed for allelic loss (LOH) and genetic instability (MSI) using 14 microsatellites intragenic to or associated with tumor suppressor or DNA mismatch repair genes. Molecular profiling identified tumors with LOH at multiple loci without microsatellite instability (MSS), tumors with high levels of LOH and low level microsatellite marker instability (MSI-L), and tumors with high levels of MSI (MSI-H), but rare LOH. K-ras mutations occurred more frequently in MSS/MSI-L carcinomas (26%) than in MSI-H colorectal tumors (10%), the latter showing a high frequency of TGFbeta type II frameshift mutations (82%). Correlation of molecular and clinical data revealed a better prognosis for stage III tumor patients displaying 5q12 loss rather than retention of heterozygosity. Thus, molecular profiling allows the identification of new prognostic markers and might facilitate the stratification of colorectal cancer patients.

Adult↗
PubMed2000

Intraoperative radiotherapy for primary and locally recurrent soft tissue sarcoma: morbidity and long-term prognosis.

INTRODUCTION: Soft tissue sarcoma has a high risk of local recurrence. Therefore, extensive surgical resection has been combined with radiotherapy to improve long-term results. Because external beam radiation doses may be limited by adjacent radiosensitive tissue, intraoperative boost radiation has been devised to achieve a higher total radiation dose in combination with external beam radiotherapy. We report our experience with this multimodal approach for primary and recurrent soft tissue sarcoma. METHODS: Clinical and pathological data were extracted from a prospective data base including all patients with a diagnosis of soft tissue sarcoma treated at the Department of Surgery, University of Heidelberg between 1988 and 1999. Intraoperative radiotherapy dosages were 12-15 Gy for the extremities and 15-18 Gy for the trunk and the retroperitoneum. Additional external beam radiotherapy was given at 40 Gy, whenever possible. RESULTS: Between 1988 and 1999, a total of 251 patients with primary or recurrent soft tissue sarcoma of the extremities, the trunk or the retroperitoneum were treated. The mean (+/- SD) age of 136 men and 115 women was 53+/-16 years. Five of 251 patients died post-operatively, giving a mortality rate of 2.0%. Intraoperative radiotherapy (IORT) was used in 92 patients (37%). Surgical complications were more frequent in IORT patients (30 of 92; 33%) compared to non-IORT patients (36 of 159; 23% P=0.1). Infectious complications were significantly more frequent in patients receiving IORT (P=0.03). Two hundred and four patients were macroscopically tumour-free (R0, R1 resection). For these patients multivariate analysis identified grading (relative risk (RR) 3.1-6.6; P<0.001), age (over 55 years; (RR) 1.8: P<0.008) and tumour location in the retroperitoneum (RR 2.2; P<0.004) as independently associated with recurrence-free survival. The use of IORT (P<0.02) reduced the relative risk of death or recurrence by 40% (RR 0.6; P<0.02). Sex, primary vs. recurrent tumour, T classification and R-status (R0 vs. R1) were not significantly related to recurrence-free survival. CONCLUSIONS: In this prospective, non-randomized study of soft tissue sarcoma IORT was associated with a higher rate of infectious complications, but the the risk of death or recurrence was reduced by 40%.

Adolescent↗
PubMed1999

[Virtual surgical planning in liver surgery].

UNLABELLED: The operability of a liver tumour depends on its three-dimensional relation to the intrahepatic vascular trees which define autonomously functioning liver (sub-)segments. The aim of our study was to establish a computer-based three-dimensional volumetric operation planning system for the liver. METHODS: Using data from routine helical CT scans the three tissue subclasses of liver parenchyma, liver vessels and liver tumour were segmented semiautomatically. A dedicated segmenting tool was established using region growing algorithms in combination with an "intelligent" border finder. Visualisation is performed by the "Heidelberg Raytracer". The vascular trees are visualised as 3D graphs. Pseudoconnections between portal and hepatic venous trees are separated automatically. Security margins are calculated and the system presents a virtual resection proposal. RESULTS: The 3D anatomy of the liver can be visualised in high quality resulting in good depth perception. Security margins are demonstrated. Dependent liver parenchyma can be recognized automatically on the basis of the vascular trees. The system offers a individualised resection proposal including the tumour, security margin and dependent liver parenchyma. CONCLUSION: Three-dimensional presentation of the individual liver anatomy of a given patient facilitates the perception of the pathology. Virtual reality combined with artificial intelligence allows calculation of complete resection protocols, which can be quantified and modified interactively. This will make operation planning more objective; patient selection may be improved, and in cases of difficult tumour localisation different resection strategies may be tested. Thus virtual reality in liver surgery will improve teaching, surgical training and planning. It may lead to improved surgical care.

Algorithms↗
PubMed1999

Sequential hepatic and pulmonary resections for metastatic colorectal cancer.

BACKGROUND: Resection of pulmonary or hepatic colorectal metastases is associated with a 5-year survival rate of 25-40 per cent. This report analyses outcome following sequential resection of colorectal metastases to both organs. METHODS: Seventeen patients with histologically confirmed colorectal adenocarcinoma and resection of liver and lung metastases were identified from a prospective database. RESULTS: The median interval between resection of the primary tumour and first metastasis was 21 (range 0-64) months. The interval between resection of the first and subsequent metastases was 18 (range 1-74) months. No patient died in the postoperative period and there were two perioperative complications. The overall survival rate in 17 patients was 70 per cent at 2 years from resection of metastasis to the second organ, but the disease-free survival rate at 2 years was only 24 per cent. CONCLUSION: Although few long-term survivors were observed in this small series, sequential resection of hepatic and pulmonary metastases is warranted in a highly selected group of patients.

Adenocarcinoma↗
PubMed1999

Multimodal therapy for squamous carcinoma of the oesophagus.

BACKGROUND: The results of surgical treatment for oesophageal squamous cell cancer have improved over recent decades, but the long-term prognosis for patients with tumours of stage II or higher is still unsatisfactory. While uncontrolled series of adjuvant or neoadjuvant treatment have reported favourable survival rates, the true benefit of multimodal treatment can be determined only by randomized controlled trials. METHODS: The literature was searched for prospective randomized controlled trials (PRCTs) examining the effect of neoadjuvant or adjuvant treatment on the long-term survival of patients with squamous cell cancer of the oesophagus. RESULTS: More than 30 PRCTs studying multimodal treatment concepts aimed at improving the prognosis of squamous cell carcinoma of the oesophagus were identified. These trials have not documented improved survival by adjuvant radiotherapy or chemotherapy. Following neoadjuvant radiotherapy or chemotherapy (or a combination of both), resectability of squamous cell carcinoma is not increased, the postoperative mortality rate appears to be higher and survival is not prolonged. CONCLUSION: Past multimodality protocols have not improved the prognosis of squamous carcinoma of the oesophagus. Careful design and reporting, together with strict control of surgical procedures, should allow more meaningful analysis of future multimodal treatment studies. At present, neoadjuvant or adjuvant treatment cannot be recommended outside such clinical protocols.

Carcinoma, Squamous Cell↗
PubMed1999

Analysis of chromosomal imbalances in sporadic and NF1-associated peripheral nerve sheath tumors by comparative genomic hybridization.

Peripheral nerve sheath tumors arise either sporadically or in association with neurofibromatosis type 1 (von Recklinghausen's neurofibromatosis, NF1) or type 2. In this study, comprehensive screening for relative chromosome copy number changes was performed on 10 benign and 19 malignant peripheral nerve sheath tumors (MPNSTs) by applying comparative genomic hybridization (CGH). In benign tumors, no chromosomal imbalances were found by CGH, whereas in MPNSTs chromosomal gains and losses were frequently detected. No differences regarding the frequency and distribution of chromosomal imbalances were observed between the 13 sporadic and 6 NF1-associated MPNSTs analyzed. In both, the number of gains was significantly higher than the number of losses, suggesting a predominant role of proto-oncogene activation during MPNST progression. Candidate regions with potentially relevant proto-oncogenes included chromosomal bands 17q24-q25, 7p11-p13, 5p15, 8q22-q24, and 12q21-q24; those with putative tumor suppressor genes were 9p21-p24, 13q14-q22, and 1p. High-level amplifications were restricted to sporadic tumors and affected eight different chromosomal subregions. In three of these MPNSTs, identical subregions on chromosomal arms 5p and 12q were coamplified. This study revealed a number of new characteristic chromosomal imbalances and provides a basis for molecular identification of oncogenes and tumor suppressor genes of pathogenetic relevance in both sporadic and NF1-associated MPNSTs. Genes Chromosomes Cancer 25:362-369, 1999.

Adolescent↗
PubMed1999

Detection of disseminated colorectal cancer cells in lymph nodes, blood and bone marrow.

Tumor progression after curative resection of colorectal cancer is caused by tumor cell dissemination, currently undetected by standard clinical staging techniques. The detection of disseminated tumor cells could help to identify a patient subgroup at risk for disease relapse who could benefit from adjuvant therapy. In addition, the significance of lymphogenic compared with hematogenic colorectal cancer cell dissemination is unknown. However, this knowledge would strongly influence the development of future therapeutic regimes. The purpose of this study was to determine the extent of colorectal cancer cell dissemination in lymph nodes compared with blood and bone marrow. Using a CK 20-reverse transcription (RT)-PCR assay, we examined 279 lymph nodes, blood, and bone marrow samples from 20 patients with colorectal cancer. Of 16 patients (11 patients stage I, 5 patients stage II) with histopathologically tumor-free lymph nodes: 14 patients (10 patients stage I, 4 patients stage II) were found to have tumor cells in paracolonic lymph nodes; 12 patients (8 patients stage I, 4 patients stage II) were found to have tumor cells in the lymph nodes along the mesentery vessels; and, remarkably, 6 patients (4 patients stage I, 2 patients stage II) were found to have tumor cells in the apical lymph nodes. In contrast, tumor cells were detected in only two blood and three bone marrow samples of these patients. Thus, lymphogenic tumor cell dissemination is a very common and early event in colorectal cancer, preceding hematogenic tumor cell dissemination. In addition, our data strongly suggest that the detection of tumor cells in the apical lymph node by CK 20-RT-PCR has prognostic relevance. Our results underline the therapeutic importance of meticulous lymph node dissection and demonstrate that the detection of lymphogenic or hematogenic tumor cell dissemination by CK 20-RT-PCR will significantly improve current tumor staging protocols.

Aged↗
PubMed1998

Liver transplantation for metastatic neuroendocrine carcinoma: an analysis of 103 patients.

BACKGROUND: Patients with neuroendocrine carcinoma often present with liver metastases not amenable to hepatic resection. For them, liver transplantation has been considered a viable treatment option, especially if hormonal symptoms and pain cannot be controlled medically. Still, little is known regarding potential prognostic factors and long-term survival after liver transplantation for neuroendocrine tumors. METHODS: A search of English, French, and German literature identified patients with liver transplantation for extensive metastases from neuroendocrine carcinoma for whom follow-up data were available. RESULTS: Overall, 2-year and 5-year survival for all 103 patients was 60% and 47%, respectively, but recurrence-free 5-year survival did not exceed 24%. Univariate analysis identified age less than 50 years, primary tumor location in lung or bowel, and pretransplant somatostatin therapy as favorable prognostic factors, whereas extended operations combining liver transplantation with upper abdominal exenteration or Whipple's procedure were associated with poor prognosis. Multivariate analysis identified age greater than 50 years (P<0.03) and transplantation combined with upper abdominal exenteration or Whipple's operation (P<0.001) as adverse prognostic factors. CONCLUSIONS: Liver transplantation may be justified in selected patients to provide immediate relief of otherwise intractable pain or hormone-related symptoms. Transplantation with curative intent appears worthwhile in young patients with only hepatic disease. In older patients with extrahepatic disease requiring extended operations, long-term results are discouraging, and the small benefit achieved by liver transplantation must be weighed against medical treatment options and the natural course of often slowly progressing disease.

Breast Neoplasms↗