Biomedical subjects

J K Seifert

Publications and source records attributed to J K Seifert.

At least 37 records · Page 2Linked to original sources

PubMed1998

Cryoablation of human colorectal cancer in vivo in a nude mouse xenograft model.

OBJECTIVE: To establish the minimum required temperature in cryoablation of human colorectal cancer cell lines grown as subcutaneous tumors in mice. METHODS: Male nu/nu nude mice were inoculated by a sc injection of 1 x 10(6) LoVo (n = 30) or C170 (n = 32) cells. After 2 weeks the tumors were frozen using a 3-mm cryotherapy probe (LCS 3000, Cryotech, UK) to temperatures ranging from -8 to -84 degreesC. RESULTS: (LoVo) Of 21 mice evaluable for analysis no tumors recurred in 3 mice which had their tumors frozen to less than -60 degreesC as measured at the presumed tumor/host boundary, whereas all but one tumor recurred in 18 mice which had their tumors frozen to >-60 degreesC. (C170) Of 18 mice evaluable for analysis 14 mice which had their tumors frozen to between -8 and -84 degreesC as measured at the presumed tumor/host boundary developed tumor recurrence. Four mice which had their tumors frozen to -11, -58, -62, and -81 degreesC did not develop tumor recurrence. CONCLUSION: Cryotherapy of subcutaneous human colon cancer xenografts in nude mice results in tumor recurrence if tumors are frozen to temperatures of as low as -60 degreesC (LoVo) or -84 degreesC (C170) with a single freeze-thaw cycle. A critical temperature for the effective cryoablation of human colorectal cancer cell lines grown as subcutaneous tumors in mice with a single freeze-thaw cycle was not defined.

Animals↗

PubMed1998

Preoperative diagnostics in pancreatic carcinoma: would less be better?

OBJECTIVE: The objective of this study was to investigate the value of preoperative diagnostics in patients with pancreatic carcinoma in terms of tumor diagnosis and evaluation of resectability. PATIENTS/METHODS: From 1 September 1985 to 31 December 1997, 408 patients shown by histology to have a ductal (n=330) or periampullary carcinoma (n=78) were treated at our hospital. RESULTS: In determining the presence of tumor, ultrasonography and computed tomography (CT) had a sensitivity of 88.3% and 94.0%, respectively; combined, they had a sensitivity of 96.2%. Endoscopic retrograde cholangiopancreatography (ERCP) had a sensitivity of 96.2%. Preoperative aspiration biopsy cytology had a sensitivity of 71.4%. No correlation was found in the patients undergoing surgery between the preoperative level of serum CA 19-9 and the presence of distant metastases. Tumor infiltration of the portal vein was shown with a sensitivity of 33.3%, 24.3%, and 76.5% and a specificity of 93.9%, 98.9%, and 65.6% by ultrasonography, CT, and angiography, respectively. Ultrasonography and CT detected liver metastases or peritoneal carcinomatosis with a sensitivity of 35.9% each and a specificity of 91.9% and 91.7%, respectively. CONCLUSION: This study shows that, in 96% of patients with pancreatic carcinoma, ultrasonography and CT are adequate for diagnosis and for the evaluation of resectability. ERCP is not the method of choice in the diagnosis of pancreatic carcinoma due to its invasiveness and to the fact that it fails to demonstrate the pathological anatomical location of the tumor; it should only be used if a tumor is suspected despite negative results on ultrasonography and CT or as an additional diagnostic method to differentiate between chronic pancreatitis and carcinoma. On account of the low sensitivity of percutaneous aspiration biopsy cytology, this method is not necessary preoperatively and may even lead to the spread of tumor cells. In 7% of patients, routine laparoscopy would additionally show liver metastases or peritoneal carcinomatosis not demonstrated using the imaging techniques.

Adult↗

PubMed1998

Lipiodol avidity of neuroendocrine liver metastases.

AIMS: Lipiodol has been shown to concentrate in most hepatocellular carcinomas as well as in some liver metastases, including those of neuroendocrine origin. Our aim was to determine the proportion of neuroendocrine liver metastases that take up lipiodol and to identify tumour characteristics that predict avidity. METHODS: Avidity was assessed in 12 patients with neuroendocrine liver metastases by performing an abdominal CT scan immediately after selective hepatic arterial injection of 5 ml of unlabelled lipiodol and this was correlated with number and size of lesions as well as angiographic and plain CT scan features. RESULTS: In seven patients the tumours displayed lipiodol avidity (four solitary, three multiple); five patients had non-avid lesions (all multiple). A large dominant liver tumour was the only predictor of avidity (mean diameter of largest lesion 9 cm vs. 3 cm for patients with non-avid tumours: P=0.01). Avidity was not related to vascularity or CT density of lesions. CONCLUSIONS: Although this is a small study, it would appear that approximately 50% of neuroendocrine liver metastases selectively concentrate lipiodol, which could have implications for targeted cancer therapy.

Adult↗

PubMed1998

Hepatic resection with cryotherapy to involved or inadequate resection margin (edge freeze) for metastases from colorectal cancer.

BACKGROUND: In patients undergoing liver resection for colorectal liver metastases, a resection edge either involved by tumour or with the tumour extending to within 1 cm is associated with a high risk of liver recurrence and survival is reduced markedly. METHODS: Twenty-six patients underwent cryotherapy of the resection edge following liver resection for metastases from colorectal carcinoma with an involved or inadequate (less than 1 cm) resection margin. RESULTS: At a median follow-up of 23 (range 1-47) months four patients were alive and disease free, and 21 had developed recurrence, of whom 13 had died. One patient died following surgery. Sixteen patients developed recurrences involving the liver, only five of which were at the resection margin. CONCLUSION: Cryotherapy to involved or inadequate resection margins improves local disease control considerably. The use of resection edge cryotherapy might allow a greater proportion of patients with liver metastases to be usefully treated and help to avoid high-risk resections.

Adult↗

PubMed1998

Prognostic factors after cryotherapy for hepatic metastases from colorectal cancer.

OBJECTIVE: To establish the prognostic importance of different patient and tumor characteristics in cryotherapy for liver metastases from colorectal cancer. SUMMARY BACKGROUND DATA: Hepatic cryotherapy has been used as a treatment of nonresectable liver metastases from colorectal cancer in almost 1000 patients worldwide, and its safety and efficacy are well established. However, tumor eventually recurs in most patients and they die of their disease. The knowledge of prognostic factors would allow the selection of patients who are more likely to benefit from this treatment and patients who may need additional treatment. METHODS: Between April 1990 and May 1997, 195 patients were treated with hepatic cryotherapy. Out of this group, the authors identified 116 patients with colorectal cancer who received cryotherapy for ablation of liver metastases. Survival was estimated with the Kaplan-Meier method, using the log-rank test for univariate analysis for significance of possible prognostic factors. For multivariate analysis, a Cox regression was used. RESULTS: One patient (0.9%) died of postoperative myocardial infarction. The total perioperative morbidity rate was 27.6%. Median survival and the 5-year survival rate were 26 months and 13.4%. The following factors were identified as independently associated with a favorable outcome: low presurgical serum level of carcinoembryonic antigen (CEA), small (< or =3 cm) diameter of cryoablated metastases, absence of untreated extrahepatic disease at laparotomy, absence of nodal involvement at primary resection, complete cryotreatment, synchronous development of liver metastases, and good or moderate differentiation of the primary tumor. Although univariate analysis suggested a favorable prognosis in patients who did not receive blood transfusion during surgery and patients younger than 51 years, this was not confirmed in multivariate analysis. In addition, normalization of the serum CEA level after treatment was an important prognostic marker in the subgroup of patients with elevated serum CEA levels before surgery. CONCLUSIONS: Hepatic cryotherapy is a safe and effective treatment option for patients with nonresectable liver metastases from colorectal cancer, with promising results regarding survival. The prognostic factors established in this series may allow better patient selection to improve the outcome in suitable patients.

Aged↗

PubMed1998

Cryotherapy of the resection edge after liver resection for colorectal cancer metastases.

BACKGROUND: An involved or inadequate (< 1 cm) resection margin is associated with a high rate of local tumour recurrence and reduced survival rates after liver resection for colorectal metastases. This paper assesses whether or not hepatic cryotherapy of the resection edge is suitable to improve local disease control. METHODS: From April 1990 to May 1997, we performed cryotherapy of the resection edge in 44 patients after liver resection for colo rectal liver metastases with an involved or inadequate resection margin. The reasons for performing edge cryotherapy instead of extension of resection were: proximity of hepatic veins or portal sheath (n = 12); avoidance of extended left or right hemihepatectomy (n = 15); inadequate liver tissue reserve after resection (n = 16); and patient unfit to undergo further major resection (n = 1). Histological examination showed the resection margin to be involved in 24 patients and close (< 1 cm) in 20 patients. RESULTS: Two patients died after surgery. Morbidity consisted of intra-abdominal collections (n = 6), postoperative bleeding (n = 1), wound infection (n = 1) and transient liver failure (n = 1). At a median follow-up of 19 months, 16 patients are alive and disease-free, 26 patients developed recurrence and 15 of them died. Nineteen patients developed recurrence which involved the liver but only five of these were at the resection edge. Median overall and liver disease-free survival was 33 and 23 months, respectively. CONCLUSIONS: Cryotherapy of the resection edge after resection of colorectal liver metastases with involved or inadequate resection margins considerably improves local disease control and may allow a greater proportion of patients with liver metastases to undergo potentially curative treatment.

Adult↗

PubMed1998

A collective review of the world literature on hepatic cryotherapy.

Published results of hepatic cryotherapy are now available for almost 900 patients. Its safety is well established and its clinical role in treating patients with unresectable hepatoma or liver metastases from colorectal carcinoma is well supported by tumour marker and survival data; the results in the treatment of neuroendocrine liver metastases are promising. Its role as an alternative to liver resection is not yet well supported by long-term data. Although different adjuvant treatment protocols have been used following the cryotherapy of colorectal liver metastases, the effect of adjuvant treatment on recurrence or survival has not been assessed in prospective studies. Laparoscopic hepatic cryotherapy is feasible in selected patients with suitable tumour locations. However, the proportion of patients who might be usefully treated with this technique is not yet well established. The mechanisms of tissue destruction by freezing are reviewed.

Animals↗

PubMed1998

[Diameter of metastases is decisive for local treatment outcome of cryotherapy of colorectal liver metastases].

In a retrospective analysis we aimed to assess the incidence of local recurrence at the cryosite as well as possible prognostic indicators for the disease-free interval at the cryosite following hepatic cryotherapy for non-resectable colorectal metastases. At a median follow-up of 22 months, 66 of 85 patients had developed tumor recurrence, involving local recurrence at the cryosite in 28 patients, with cryoablated metastases of > 3 cm being associated with shorter disease-free intervals at the cryosite. Improvements in probe placement and monitoring of the freezing process are required to allow successful treatment of large liver metastases.

Adult↗

PubMed1997

Bile duct warmer in hepatic cryosurgery--a pig liver model.

Freezing of the common bile duct resulted in injury, stenosis, or perforation of the bile duct in a dog model. Biliary cutaneous fistulas and bile leaks are reported as complications of hepatic cryosurgery in man. In an ex vivo pig liver model we compared freezing close to the bile duct with and without warming the bile duct with warmed saline solution via an inserted catheter ("bile duct warmer"). The recorded temperatures at the outer wall of the bile duct were -50 degrees C after 10 min of freezing without and 5. 8 degrees C with the use of the warmer (P < 0.001, two-way ANOVA). The bile duct warmer system may be a simple and inexpensive device in reducing perioperative morbidity after hepatic cryosurgery of hepatic liver lesions close to a bile duct.

Animals↗

PubMed1997

[Repeat interventions in metastases].

Between 1985 and 1994, 262 patients with metastases underwent resectional treatment in the Department for General and Abdominal Surgery of the University of Mainz. Twenty-seven patients with recurrent metastases were treated with repeat resections. The records of these 27 patients were reviewed and analyzed. After 42 repeat resections, 4 of 27 patients (14.8%) developed complications. Three of 27 patients died in the postoperative period (11.1%). For patients with R0 resection of metastases from colorectal primaries the median survival time was 69 months after resection of the primary tumor (n = 16), 38 months after the first resection of metastases (n = 15), and 25 months after the second resection of metastases (n = 15). After the last repeat resection of metastases in each patient, median survival was 25 months in patients with R0 resection (n = 11), compared to 7 months following R1/2 resection (n = 5) (P = 0.007). Disease-free survival following first R0 resection of colorectal metastases (n = 15), was not significantly different from disease-free survival following repeated R0 resection of colorectal metastases (n = 21). Patients with repeat resection of colorectal liver metastases (n = 9) had longer disease-free survival (median 18 months) than patients with repeat resection of colorectal metastases in organs other than liver or lungs (median 4 months; n = 4) (P = 0.005). Repeat resections for metastases are characterized by low operative risk and a prognostic benefit for highly selected patients.

Adult↗

PubMed1997

[Standards and controversies in preoperative bowel preparation].

Bowel preparation for colorectal surgery should lead to sufficient bowel cleansing and reduction of fecal bacterial levels. It should be well tolerable for the patient and side effects should be rare. Finally the costs should be low. Today there are mainly three methods of significance: whole gut lavage, oral bowel preparation with Golytely-solutions and Prepacol (combination of bisacodyl tablets and sodium sulphate solution). We completed a prospective cohort study including 100 patients undergoing colorectal surgery in our hospital, comparing whole gut lavage with Fordtran, a new oral polyethylene glycol solution. In patients prepared with whole gut lavage the serum chloride levels and the body weight increased significantly more, the frequency of vomiting and subjective irritation was higher. There were no differences concerning the bowel cleansing effect and frequency of postoperative complications in both groups. The costs for oral polyethylene glycol solution are considerably lower. Our results match well with the published experiences of other authors. After bowel preparation with Prepacol a higher frequency of postoperative complications is reported. Due to better patient acceptance, lower side effects and lower costs, oral polyethylene glycol solutions are recommended as preoperative bowel preparation.

Cathartics↗

PubMed1997

[111-indium DTPA octreotide scintigraphy in colorectal liver metastases].

The somatostatin analogue octreotide is effective in the treatment of neuroendocrine and other tumours. 111-In-labelled DTPA-octreotide scintigraphy is successful in localizing primary neuroendocrine tumours and metastases and other tumours containing somatostatin receptors. An antiproliferative effect of octreotide was also demonstrated for colorectal carcinoma. Since only about 40% of colorectal carcinomas express somatostatin receptors, we tried to establish whether 111-In-labelled DTPA-octreotide scintigraphy is able to reveal the receptor status of liver metastases in patients with colorectal liver metastases. This would be useful in selecting patients for adjuvant therapy studies with octreotide. We performed 111-In-labelled DTPA-octreotide scintigraphy in ten patients with nonresectable liver metasoffes of colorectal origin and curatively resected primary. In nine of ten patients the liver metastases were somatostatin receptor negative, in one patient somatostatin receptor positive. In the patient with somatostatin receptor-positive liver metastases after resection of a rectal carcinoma, the histological examination of the biopsies from the liver metastases showed a solid tumour of neuroendocrinal differentiation. In the repeated histological examination of the specimen of the rectal primary, a small solid tumour with neuroendocrinal differentiation was found between formations of adenocarcinoma (adenoendocrine carcinoma). In our study 111-In-labelled DTPA-octreotide scintigraphy did not indicate the receptor status of liver metastases from colorectal carcinoma and was not useful in the planning of therapeutic regimens. For the diagnosis of the receptor status of colorectal liver metastases autoradiographic investigation on tissue biopsies are still necessary. In patients with adenoendocrine carcinomas 111-In-labelled DTPA-octreotide scintigraphy may help to histologically differentiate the metastases.

Adenocarcinoma↗

PubMed1996

[Resection of liver metastases of colorectal tumors. A uni- and multivariate analysis of prognostic factors].

Between September 1985 and December 1994, liver resections with curative intent were performed for liver metastases of colorectal primaries in 76 patients at the department for abdominal surgery of the university of Mainz. Perioperative morbidity and 30-day mortality rates were 30.3% and 6.6% respectively. The 3- and 5-year survival rate was 53% and 36% respectively. For patients with complete tumor removal (R0 resection), excluding perioperative mortality, the following factors were associated with more prolonged survival after hepatic resection in univariate analysis. N1 stage of the colorectal primary compared to N2 stage (in patients with positive mesenterial lymph nodes); diameter of the largest metastasis between 2.1 and 3.5 cm; postoperative normalized CEA level (in patients with CEA level elevated to more than 4 ng/dl preoperatively); and wedge resections compared to hemihepatectomies. Regarding disease-free survival, only N1 stage of the colorectal primary compared to N2 stage and diameter of the largest metastasis between 2.1 and 3.5 cm had a positive influence. In multivariate analysis, the diameter of the largest metastasis was the only factor associated with survival time, while disease-free survival was influenced by the largest diameter of the metastasis, patient sex and N stage of the colorectal primary. Whether adjuvant therapies (systemic or regional chemotherapy) after curative resection of colorectal liver metastases is associated with better survival times remains an open question. Some of the above-mentioned prognostic factors may be helpful in selecting patients for entry into adjuvant therapy protocols.

Adult↗

PubMed1996

[Liver resections of metastases of non-colorectal primary tumors].

The records of 30 patients who had hepatic resections for non-colorectal liver metastases between 1985-1994 were analyzed retrospectively. The perioperative morbidity and mortality rates were 7% (2/30) and 3% (1/30). The patient group with curative resection (n = 25) was found to have a 5-year survival rate of 44.6% and a 3-year disease-free survival rate of 19.8%. By univariate analysis, the number of metastases and the amount of perioperative blood replacement were the only factors that affected survival after curative resection. Synchronous vs. metachronous disease was the only factor that showed a significant influence on disease-free survival after curative resection. Although the benefit of liver resection for non-colorectal metastases is limited, surgical therapy can be performed safely and offers some patients a chance of long-time survival.

Adolescent↗

PubMed1995

[Orthograde intestinal irrigation or Fordtran solution for bowel preparation in elective colorectal surgery. Prospective outcome study].

In a prospective cohort study, which was carried out at the department for abdominal surgery of the university of Mainz from June to December 1993, two methods of bowel preparation for elective colorectal surgery were compared: oral bowel preparation with Fordtran a new polyethylene glycol solution (63 patients), and whole-gut lavage with Ringer's solution (37 patients). The serum chloride levels and the bodyweight increased significantly more in the whole-gut lavage group. These patients also showed a higher frequency of vomiting during bowel preparation. Neither the bowel cleansing effect nor the postoperative complications differed significantly between the two groups. Owing to these results, the better patient acceptance, and the easier handling and lower costs of PEG solution, we recommend this method of preoperative bowel preparation for elective colorectal surgery.

Adult↗

PubMedDate not supplied

Value of quantitative DNA analysis in endocrine tumors of the pancreas.

BACKGROUND: The diagnosis of malignancy can be difficult in endocrine tumors of the pancreas. Moreover prognostically relevant factors are not available. The aim of this study was to evaluate retrospectively whether the DNA distribution pattern can differentiate between benign and malignant pancreatic endocrine tumors and secondly whether the DNA content of tumor cells gives prognostic information. METHOD: Image cytometry of paraffin-embedded tumor material of 42 pancreatic endocrine tumors. RESULTS: In 27 benign endocrine pancreatic tumors (25 insulinomas, 2 benign nonfunctioning endocrine tumors) we could differentiate between 6 diploid, 15 hypotriploid and 6 triploid DNA histograms. In 15 malignant endocrine tumors of the pancreas we could differentiate between 1 diploid, 1 hypotriploid, 9 triploid and 4 hypertriploid tumors. All 4 patients with a hypertriploid tumor died as a consequence of their disease in contrast to only 1 patient with a diploid, hypotriploid or triploid tumor even in case of a nonradical resection. CONCLUSION: With the help of quantitative DNA measurement a differentiation between malignant and benign endocrine pancreatic tumors is not possible even if the risk of malignancy increases with the DNA content. The DNA content of malignant endocrine pancreatic tumors has an influence on the long-term survival. Hypertriploid tumors have a statistically significantly worse prognosis than diploid, hypotriploid or triploid tumors.

Adenoma↗

PubMedDate not supplied

Liver resection for breast cancer metastases.

BACKGROUND/AIMS: The prognosis of patients with hepatic metastases (HM) from breast cancer receiving no treatment is extremely poor. Results of systemic and regional chemotherapy as well as other treatment modalities, such as immunotherapy or hormonal therapy, are disappointing in this group of patients, with median survival rates hardly exceeding 1 year. METHODOLOGY: We performed a retrospective analysis of patients undergoing resection of isolated HM from breast cancer to determine the morbidity, mortality and prognosis following this procedure. RESULTS: Fifteen female patients underwent liver resection between September 1985 and April 1997. Two patients had synchronous and 13 patients had metachronous HM. The mean number of HM was 3.3 (1-9) (bilobar in 6 patients) with a mean diameter of 5.3 cm (2-11 cm). The following resections were performed: wedge resection (4), left lateral segmentectomy (2), right hemihepatectomy (3), left hemihepatectomy (1), extended right hemihepatectomy (3) and extended left hemihepatectomy (2). There was no hospital mortality. Morbidity (transient hepatic failure (n=2) and intra-operative hemorrhage necessitating splenectomy (n=1)) occurred in 3 patients. Median follow-up was 12 (1-88) months. Six patients developed recurrent liver disease; 2 relapsed elsewhere. Six of these 8 patients died. Overall median survival following liver resection was 57 months with 1-, 2- and 3-year survival rates of 100%, 71.4% and 53.6% respectively. CONCLUSIONS: Liver resection is a viable treatment option for selected patients with isolated HM from breast cancer that can be performed safely. It should be considered in individual patients if the operative risk is low, if no extrahepatic disease is present and provided a complete resection with clear margins is technically feasible.

Adult↗

PubMedDate not supplied

Prognostic factors following liver resection for hepatic metastases from colorectal cancer.

BACKGROUND/AIMS: We aimed to identify prognostic factors that may allow better patient selection for liver resection for colorectal liver metastases. METHODOLOGY: A retrospective analysis of the files of 120 patients undergoing liver resection for colorectal metastases between 9/85 and 12/96 was performed. Survival and disease-free survival were calculated, and a uni- and multivariate analysis for the prognostic impact of various perioperative factors on survival was performed. RESULTS: Perioperative morbidity and mortality were 28.3% and 5.8% respectively. Median overall survival was 30 months with a 5-year survival rate of 31%. Radicality was the prime prognostic determinant. In patients with R0-resection, a liver metastasis of > 3.5 cm in diameter was the only independent factor associated with an adverse prognosis. CONCLUSIONS: Liver resection for colorectal liver metastases should be attempted if complete resection with clear margins is feasible and may be especially beneficial in patients with small (< or = 3.5 cm) lesions.

Adult↗