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J K Seifert

Publications and source records attributed to J K Seifert.

At least 19 recordsLinked to original sources
PubMed2000

Comparison of iceball diameter and temperature distribution achieved with 3-mm accuprobe cryoprobes in porcine and human liver tissue and human colorectal liver metastases in vitro.

We aimed to assess the thermal profile and size of iceballs produced by Accuprobe cryoprobes in fresh porcine and human liver and human colorectal cancer liver metastases in vitro to allow better planning of cryosurgical treatment of liver metastases. Iceballs were produced by a 20-min single freeze cycle using 8-mm cryoprobes in pig liver in a waterbath at 37 degrees C (n = 8) and 3-mm cryoprobes in pig liver (n = 8), human liver (n = 3), and human colorectal cancer liver metastases (n = 8). The iceball diameters and the temperatures at different distances from the cryoprobe were measured. Mean iceball diameters produced by 8-mm cryoprobes in pig liver were 56.3 mm and varied from 38.7 to 39.6 mm for 3-mm cryoprobes in the different tissues used. There was no significant difference in iceball size in the different tissues. The diameter of the zone of -40 degrees C or less was approximately 44 mm using 8-mm cryoprobes in porcine liver and between 27 and 31 mm using 3-mm cryoprobes in the different tissues examined. The results may allow better preoperative planning of the cryosurgical treatment of liver metastases with Accuprobe cryoprobes.

Animals↗
PubMed2000

Cryotherapy for liver metastases.

Cryotherapy is undergoing a renaissance in the treatment of nonresectable liver tumors. In a prospective case control study we assessed the morbidity, mortality, and efficacy of hepatic cryotherapy for liver metastases. Between January 1996 and September 1999 a total of 54 cryosurgical procedures were performed on 49 patients (median age 66 years, 21 women) with liver metastases. Patient, tumor, and operative details were recorded prospectively. Liver metastases originated from colorectal cancer (n=37), gastric cancer (n=3), renal cell carcinoma (n=2), and other primaries (n=7). Median follow-up was 13 months (1-32). The median number of liver metastases was 3 (range 1-10) with a median diameter of 3.9 cm (range 1.5-11). Twenty-one patients (43%) had cryoablation only, and 28 (57%) had liver resection in combination with cryoablation. One patient (2%) died within 30 postoperative days. Another 13 patients (27%) developed reversible complications. In 19 of 25 patients (76%) with preoperatively elevated serum CEA and colorectal metastases it returned to the normal range postoperatively. Twenty-eight patients (57%) developed tumor recurrence, eight of which with involvement of the cryosite. Overall median survival patients was 23 months, and survival in patients with colorectal metastases was 29 months. Hepatic cryotherapy is associated with tolerable morbidity and mortality. Efficacy is demonstrated by tumor marker results. Survival data are promising; however, long-term results must be provided to allow comparison with other treatment modalities.

Adult↗
PubMed2000

Resection with cryotherapy of colorectal hepatic metastases has the same survival as hepatic resection alone.

BACKGROUND: Hepatic resection is well established as a potentially curative treatment for hepatic colorectal cancer metastases. However, only a small proportion of patients with liver metastases are suitable for resection because they either have extrahepatic disease, or the extent and/or the distribution of their hepatic disease would make excision impossible. We have previously described the use of cryotherapy for inadequate resection margins and lesions in the remaining lobe of the liver. Combining such cryodestructive techniques with resection offers the possibility of increasing the proportion of patients to whom potentially curative treatment can be offered. The aim of this study was to compare survival in patients treated with resection and cryotherapy against those of patients treated with resection alone. Potential prognostic variables were also examined. METHOD: Patients undergoing a hepatic resection with or without cryotherapy at our unit between April 1990 and July 1997 were identified from our database and their notes reviewed. Survival was estimated using the Kaplan-Meier method and compared using the Log rank test. RESULTS: One hundred and seven patients were treated in total: 32 underwent resection alone, and 75 underwent resection combined with cryotherapy. There was no significant difference between the survival of patients treated with resection alone and those treated with resection and cryotherapy. CONCLUSIONS: Edge and contralobe cryotherapy can be combined with hepatic resection to allow a greater proportion of patients with hepatic colorectal metastases to be offered treatment, and results in similar survival figures comparable to hepatic resection for at least 3 years.

Adult↗
PubMed1999

Pretreatment echogenicity of colorectal liver metastases predicts survival after hepatic cryotherapy.

PURPOSE: There is currently no knowledge of the prognostic value of echogenicity of colorectal liver metastases in patients receiving no treatment, hepatic cryotherapy, or any other treatment modality. We sought to determine whether differences in echogenicity of colorectal liver metastases predict prognosis after hepatic cryotherapy. METHODS: Between April 1990 and May 1997 the echogenicity of liver metastases was assessed intraoperatively in 48 patients undergoing cryotherapy for in situ destruction of colorectal liver metastases, with use of an Aloka machine with a 5-MHz scanner. Survival time was calculated by the Kaplan-Meier method, and the prognostic value of echogenicity and several other possible prognostic factors was tested with the log-rank test. RESULTS: Thirty-three patients were found to have hyperechoic metastases. These patients had a favorable outcome, with a median survival time of 50 months, as compared with a median survival time of 24 months in the 15 patients with hypoechoic metastases (P = 0.0074). Regarding the remaining prognostic factors that were tested, only age less than 51 years, absence of involved nodes at primary resection, small diameter of liver metastases, and low preoperative serum carcinoembryonic antigen levels were associated with a favorable outcome. CONCLUSION: We believe that this is an original description of the prognostic importance of echogenicity of colorectal liver metastases. Differences in echogenicity may be related to tumor biology. This will be addressed in further studies.

Adult↗
PubMed1999

World survey on the complications of hepatic and prostate cryotherapy.

Cryotherapy is used as a treatment for nonresectable liver tumors and adenocarcinoma of the prostate. Morbidity and mortality following cryotherapy are generally considered to be infrequent, but a syndrome of multiorgan failure, severe coagulopathy, and disseminated intravascular coagulation following hepatic cryotherapy has been described and referred to as the cryoshock phenomenon. In this study we aimed to assess and describe the incidence and clinical features of the cryoshock phenomenon following cryosurgery from the surveyed experience of a large number of clinical centers and to relate the data to the overall mortality and morbidity of this treatment. A questionnaire was sent to all cryotherapy users (n = 299) of whom we were aware. We requested information on the number of patients treated, the occurrence, and the clinical features of cryoshock and mortality and morbidity following cryotherapy of the prostate or liver. Altogether 134 completed questionnaires were returned (44.8%). Seventy-two centers had experience with hepatic cryotherapy and 62 with prostate cryotherapy. Following hepatic cryotherapy, the phenomenon of cryoshock was observed in 21 of 2173 patients (1%) and was responsible for 6 of 33 perioperative deaths (18.2%). Cryoshock was rare following prostate cryotherapy (2 of 5432 patients, 0.04%) and did not contribute to the overall mortality of 0.06%. Hepatic and prostate cryotherapy are safe. Cryoshock is rare after prostate cryotherapy but occurs in 1% of patients following hepatic cryotherapy. Cryoshock is associated with a high risk of death, being responsible for 18.2% of deaths in this survey. Research regarding the mechanism and possible avoidance of cryoshock is required.

Acute Kidney Injury↗
PubMed1999

Interleukin-6 and tumor necrosis factor-alpha levels following hepatic cryotherapy: association with volume and duration of freezing.

Although morbidity following cryotherapy is usually minor, a syndrome of multiorgan failure and disseminated intravascular coagulation (DIC) has been described and referred to as the cryoshock phenomenon. We hypothesized that mediators similar to those in septic shock may be involved in this syndrome. In this study we aimed to assess the plasma concentrations of the cytokines tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) following hepatic cryotherapy and to relate them to the duration and volume of freezing and to hepatocellular injury. Between April and December 1997 blood samples were taken preoperatively and at different times postoperatively from patients undergoing hepatic artery catheter-insertion (HAC) (n = 15), cryotherapy (n = 5), liver resection (n = 9), liver resection and edge cryotherapy (n = 7), or liver resection and cryotherapy of additional lesions (n = 9). They were analyzed for serum aspartate transaminase (AST) and plasma TNF-alpha and IL-6 levels. There was a significant association (Pearson correlation) of serum AST levels 1 hour postoperatively with plasma TNF-alpha and IL-6 levels at the end of the procedure. In patients undergoing cryotherapy or resection with cryotherapy of additional lesions (n = 14), the volume and duration of hepatic freezing were significantly associated with postoperative serum AST and plasma TNF-alpha and IL-6 levels at various postoperative times. Hepatic cryotherapy is followed by cytokine release, with postoperative plasma TNF-alpha and IL-6 levels associated with the degree of hepatic cryotrauma. These mediators may be involved in the occurrence of cryoshock following large-volume hepatic freezing.

Aspartate Aminotransferases↗
PubMed1999

Indicators of recurrence following cryotherapy for hepatic metastases from colorectal cancer.

BACKGROUND: This retrospective review aimed to assess the incidence of local recurrence at the cryosite, hepatic and extrahepatic recurrence and the corresponding disease-free intervals. Prognostic indicators following hepatic cryotherapy were also identified. METHODS: Eighty-five patients underwent complete cryotreatment of colorectal liver metastases between April 1990 and May 1997. Possible prognostic indicators were tested for their impact on the disease-free interval at the cryosite, liver disease-free survival and overall disease-free survival with univariate and multivariate analysis. RESULTS: At a median follow-up of 22 months 66 patients developed tumour recurrence: 18 in the liver only; 15 in the liver and lung; 22 in the liver and extrapulmonary areas; and 11 at extrahepatic sites only. Local recurrence at the cryosite occurred in 28 patients. Cryotreated metastases larger than 3 cm were associated with a shorter disease-free interval at the cryosite and liver disease-free survival; persistently raised serum carcinoembryonic antigen (CEA) levels after operation were associated with shorter liver disease-free and overall disease-free intervals in multivariate analysis. CONCLUSION: Improvements in probe placement and monitoring of the freezing process are required to allow successful treatment of large liver metastases. A failure in complete postoperative CEA response indicates that hepatic or extrahepatic disease was not detected before operation, which may be avoided with better staging procedures.

Adult↗
PubMed1998

[Cryotherapy of liver metastases. Initial results].

PATIENTS AND METHOD: Between 1 Jan 1996 and 1 Apr 1998 29 patients underwent cryosurgical therapy for liver metastasis at the Department of Surgery at the University of Mainz. RESULTS: No complications occurred following cryosurgery alone (n = 12). Within the group of patients with a combined procedure (n = 11) 1 patient had temporary liver failure and 1 patient died of sepsis. Following freezing of the cutting zone (n = 6) 1 patient showed a bile fistula and 1 ascites. In 15 cases of 28 dismissed patients with remaining destroyed tumor tissue the follow-up showed no tumor recurrence (median follow-up 11 months). On the other hand 9 patients had a tumor recurrence within the liver, 3 patients at extrahepatic regions and 7 patients developed a tumor recurrence within the freezing zone.

Colorectal Neoplasms↗
PubMed1998

Cryotherapy for neuroendocrine liver metastases.

While the prognosis for patients with untreated liver metastases from neuroendocrine primaries is rather good, they often suffer disabling symptoms due to syndromes of hormonal excess. Thirteen patients with metastatic neuroendocrine tumours were treated by hepatic cryotherapy; seven patients were symptomatic and five of these had elevated levels of hormonal tumour markers. Twelve patients are alive and mostly asymptomatic with a median follow up of 13.5 months; one patient died after 45 months of bronchopneumonia without evidence of tumour recurrence. All patients with elevated preoperative tumour markers have had a significant fall in markers postoperatively. Two patients were returned to the operating theatre for coagulopathy-associated bleeding: one patient each developed acute renal failure and pulmonary embolism, but there was no mortality. This study shows that hepatic cryotherapy offers a useful treatment option for this group of patients, alleviates symptoms and may have an impact on survival.

Adult↗
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↗