Clinical value of loss of heterozygosity in serum microsatellite DNA of patients with gastrointestinal stromal tumors.

GOALS: To study the role of loss of heterozygosity (LOH) in serum microsatellite DNA of patients with gastrointestinal stromal tumors (GIST). BACKGROUND: In GIST, tumor markers from peripheral blood are missing. STUDY: Seventy-eight patients (59 GIST, 13 leiomyomas, 2 leiomyosarcomas, and 4 schwannomas) underwent resection at our institute between 1985 and 2006. Thirty-three preoperative sera (26 GIST and 7 non-GIST) and 62 postoperative sera (47 GIST and 15 non-GIST) were available and tested for alterations in 12 representative microsatellite loci on chromosomes 22, 17, 13, 9, and 3, using fluorescence-based automated capillary electrophoresis by ABI Prism. Survival was calculated with Kaplan-Meier plots. RESULTS: Seventeen out of 26 GIST patients had a positive preoperative serum LOH score (> or =2 LOH, sensitivity 65.4%), and 6 out of 7 non-GIST patients had a negative score (< or =1 LOH, specificity 85.7%, P=0.030, Fisher exact test). Serum LOH in GIST were strongly correlated with Fletcher risk groups (P=0.016, chi test). All metastasized GIST (7/7) showed > or =2 LOH preoperatively. Postoperative sensitivity and specificity of LOH analysis for prediction of relapse in 47 GIST was 75.0% and 64.1%, respectively. After a median observation time of 51.3 months (95% confidence interval, 39.4-61.4), LOH in serum significantly predicted overall survival (P=0.007, log-rank test). CONCLUSIONS: LOH serum analysis in GIST may play a role as a noninvasive, differential diagnostic, prognostic, and monitoring marker in the clinical routine.

Subset of esophageal adenocarcinoma expresses adhesion molecule l1 in contrast to squamous cell carcinoma.

BACKGROUND: Esophageal adenocarcinoma is currently the most rapidly increasing cancer in Western populations. L1 (CD171), a neural cell adhesion molecule, has an essential function in tumor progression and has been shown to be expressed in the proliferating cells of the intestinal crypts in mice. The aim of the current study was to determine L1 expression in esophageal cancer and to evaluate whether L1 could serve as a potential marker and therapeutic target for this tumor type. MATERIALS AND METHODS: L1 expression was assessed on a tissue microarray with 257 surgically resected esophageal cancer samples by immunohistochemistry with a monoclonal antibody (Clone UJ127). L1 expression was correlated with clinicopathological data. RESULTS: L1 was detected in 22 (9%) of 257 esophageal cases, whereas 235 (91%) were L1 negative. Nineteen (86%) of the 22 L1-positive cases were adenocarcinoma. Cross table analysis showed a significant association between L1 expression and adenocarcinoma subtype (p<0.001), but not squamous cell carcinoma. CONCLUSION: L1 expression in a subgroup of esophageal cancer is specifically prevalent in adenocarcinoma. Data suggest L1 as a potential target for biological therapy in L1-positive esophageal adenocarcinoma patients.

Midkine as a prognostic marker for gastrointestinal stromal tumors.

PURPOSE: Midkine (MK), a heparin-binding growth factor, has an important role in cancer progression. The outcome of patients with gastrointestinal stromal tumors (GISTs) is correlated with tumor size and mitotic count. The aim of this study was to determine MK expression in GISTs. METHODS: Midkine was detected in 31 (55%) of 57 surgically resected GISTs by immunohistochemistry with a rabbit antibody against MK and peroxidase method. RESULTS: A significant worse outcome of MK-positive patients was found (P < 0.05; log rank test). Multivariate Cox regression analysis showed an independent prognostic impact (relative risk for overall survival 3.64; P < 0.05). Interestingly, MK expression was significantly associated with mitotic rate (P < 0.05; Chi-squared test), but not with tumor size (P = 0.97). CONCLUSIONS: Taken together, MK is a prognostic marker for GIST patients. MK might also be a useful peripheral tumor marker since it can be detected in peripheral serum. Future studies should involve higher GIST patient numbers including tumor and serum samples for detection of MK.

Short tandem repeat polymorphisms of exon 4 in Kazal-type gene ECRG2 in pancreatic carcinoma and chronic pancreatitis.

BACKGROUND: Short tandem repeat (STR) polymorphisms in exon 4 of the Kazal-type esophageal cancer related gene (ECRG2) have been reported to be associated with esophageal carcinoma. Kazal-type genes are associated with cancer and pancreatic disease. The aim of the present study was to examine whether ECRG2 STR polymorphisms are associated with pancreatic carcinoma and chronic pancreatitis. MATERIALS AND METHODS: A total of 209 surgically treated patients were analyzed, 92 with pancreatic adenocarcinoma and 117 with chronic pancreatitis. We retrospectively analyzed genomic DNA from peripheral blood leukocytes for STR TCA3/TCA3, TCA3/TCA4 and TCA4/TCA4 in the noncoding region of exon 4 of ECRG2. Associations between STRs and survival of cancer patients were investigated using log-rank test. RESULTS: ECRG2 STR of highest incidence was TCA3/TCA3 [47 (51%) in pancreatic carcinoma; 59 (50%) in pancreatitis patients], followed by the TCA3/TCA4 [37 (40%); 54 (46%)] and TCA4/TCA4 [8 (9%); 4 (4%)] genotypes. No correlation in frequency of STRs comparing chronic pancreatitis and pancreatic cancer was determined using the Chi-squared test (p = 0.23). STR polymorphisms were not significantly associated with reduced tumor-specific or overall survival (p > 0.05; log-rank test). CONCLUSION: The data show that ECRG2 STR polymorphism TCA3/TCA3 in exon 4 is the most prevalent polymorphism found in pancreatic adenocarcinoma and chronic pancreatitis detected in peripheral blood. None of the polymorphisms was associated with poor clinical outcome in pancreatic cancer patients.

Microsatellite DNA alterations of gastrointestinal stromal tumors are predictive for outcome.

PURPOSE: In gastrointestinal stromal tumors (GIST), loss of heterozygosity (LOH) on chromosome 22 and its presumptive biological function has been described. The prognostic value of these and other DNA regions for patient survival remains unclear. EXPERIMENTAL DESIGN: Sixty patients who underwent surgery at our institution between 1992 and 2003 for GIST were histopathologically reclassified by immunohistochemistry and the GIST consensus group criteria 2001. Twenty-one microsatellite loci on chromosomes 3, 9, 13, 17, 18, and 22 were screened for alterations in tumor and healthy DNA. Survival was calculated by Kaplan-Meier plots. RESULTS: Eleven (18.3%) of 60 patients showed metastases at presentation. Thirteen (21.7%) of 60 were high-risk GISTs. LOH was found in all tumors. Twenty-eight (46.7%) of 60 showed more than two LOH in 21 microsatellite marker sites. The frequency of single marker LOH varied from 1.7% to 28.3% among tumors. Frequent LOH was found on chromosomes 22 and 17. The correlation of LOH positivity and the consensus scoring was significant (P=0.005, chi2 test). After a median observation time of 33.3 months (95% confidence interval, 23.9-42.6), overall survival was best for patients with tumors of very low, low, and intermediate risks with only 6 of 36 death events, whereas 14 of 24 high-risk and metastasized patients had died (P<0.001, log-rank test). Likewise, LOH significantly predicted survival (P=0.013) and the effect was particularly detrimental for LOH on chromosome 17 (P<0.001). CONCLUSIONS: LOH is a useful phenomenon for the prognosis of GIST. Rather than chromosome 22 markers, chromosome 17 markers independently predict survival.

Allelic loss of Hox11L1 gene locus predicts outcome of gastrointestinal stromal tumors.

Loss of heterozygosity (LOH) in tumors has been described to have prognostic impact. Hox11L1 gene, located on chromosome 2, has a role in proliferation of neuronal myenteric Cajal cells being the progenitor cells of GISTs. The aim was to examine the frequency and prognostic value of allelic loss of Hox11L1 gene locus in GISTs. Tumor and control DNA of 72 GIST patients was extracted after microdissection from tissue sections. Patients underwent surgery between 1992 and 2003 and were histopathologically reclassified. Microsatellite marker D2S286 on chromosomes 2 near Hox11L1 gene locus was used for detection of LOH by PCR and capillary electrophoresis. Survival was calculated by Kaplan-Meier plots. LOH was found in 7 (10%) of 72 GISTs. Fifty-four (75%) cases did not show LOH. Eleven (15%) were homozygous and consequently non-informative. Survival analysis (n=59) revealed a significantly worse tumor-specific and relapse-free survival for GIST patients with LOH in the tumor by univariate analysis (p<0.05 by log-rank test; median follow-up time 37 months). LOH of Hox11L1 gene locus is a useful parameter for prognosis of GIST. The data propose that Hox11L1 has a role in tumorigenesis in GISTs.

Oxygen radical formation does not have an impact in the treatment of severe acute experimental pancreatitis using free cellular hemoglobin.

AIM: Microcirculatory dysfunction and free oxygen radicals are important factors in the pathogenesis of severe acute pancreatitis. Additional oxygen delivery might enhance lipid peroxidation but may also improve pancreatic microcirculation. This study assesses the effect of free cellular bovine hemoglobin on the formation of oxygen radicals and microcirculation in a rodent model of severe acute pancreatitis. METHODS: Fifteen minutes after induction of acute pancreatitis Wistar rats received either 0.8 mL bovine hemoglobin (HBOC-200), hydroxyethyl starch (HES) or 2.4 mL of normal saline to ensure normovolemic substitution. After 6 h of examination the pancreas was excised and rapidly processed for indirect measurement of lipid peroxidation products malondialdehyde (MDA) and reduced glutathione (GSH) in pancreatic tissue. RESULTS: The single application of HBOC-200 improved pancreatic microcirculation and reduced histopathological tissue damage significantly. Tissue concentration of MDA did not differ between the groups. Also no differences in GSH levels were detected. CONCLUSION: Though the single application of HBOC-200 and HES improve pancreatic microcirculation, no differences in lipid peroxidation products were detected. The beneficial effect of additional oxygen supply (HBOC-200) does not lead to enhanced lipid peroxidation.

The role of vascular adhesion molecules PECAM-1 (CD 31), VCAM-1 (CD 106), E-selectin (CD62E) and P-selectin (CD62P) in severe porcine pancreatitis.

Inflammatory cytokines have been shown to mediate organ damage by their action on vascular endothelia and leukocytes, in part by upregulating the expression of adhesion molecules, which in turn convey transmigration of leukocytes into tissue. The upregulation and activation of vascular cell adhesion molecules on the endothelial cells avail firm leukocyte adhesion to the vascular endothelium and enhance their transmigration and consecutive tissue injury. The aim of this study was to evaluate the expression of vascular adhesion molecules CD 31 (PECAM-1), CD 106 (VCAM-1), CD 62E (E-Selectin) and CD 62P (P-Selectin) in the pancreas and distant organs of pigs suffering from acute necrotizing pancreatitis (AP). AP was induced in 13 pigs by a combination of intravenous cerulein and intraductal glycodeoxycholic acid. For immunostaining of vascular adhesion molecules slides of porcine pancreas, lung, kidney and liver tissue were stained with monoclonal antibodies (Ab) against PECAM-1-1, VCAM-1 E- and P- SELECTIN. The endothelial cell expression of CD 31 (PECAM-1), CD 106 (VCAM), CD 62E (E-Selectin) and CD 62P (P-SELECTIN) in severe porcine pancreatitis is detectable and upregulation is partly significantly.

Radical redo surgery for local rectal cancer recurrence improves overall survival: a single center experience.

BACKGROUND: To date, the survival benefit of redo surgery in locally recurrent rectal adenocarcinoma remains unclear. STUDY DESIGN: In an institutional study, operations for recurrence were retrospectively analyzed. Survival was calculated using the Kaplan-Meier plot and Cox regression analysis. RESULTS: A total of 72 patients with local recurrence were explored or resected. In 38 patients, there was synchronous distant organ recurrence. Forty-five of 72 were re-resected and in 37 of 45 cases, R0 situations were achieved. In 11 of 38 metastasized patients, both local and distant organ recurrence were successfully removed. For obtaining tumor control, resections of inner genitals, bladder, and sacral bone were necessary in 10, 4, and 11 patients, respectively. Survival was better for patients re-resected with a median overall survival of 54.9 months, as compared with 31.1 months among non-resected patients (p = 0.0047, log-rank test). Subgroup analysis revealed that a benefit of re-resection was observed to a lesser extent in synchronous local and in distant disease. Cox analysis showed that initial Dukes stage and complete resections of local recurrences were independently determining prognosis (relative risk 1.762 and 0.689, p = 0.008 and p = 0.002, respectively). CONCLUSIONS: Radical surgery for local recurrence can improve survival if complete tumor clearance is achieved, and concomitant distant tumor load should not principally preclude re-resection.

Aggressive surgery improves long-term survival in neuroendocrine pancreatic tumors: an institutional experience.

OBJECTIVE: To evaluate surgical strategies for neuroendocrine pancreatic tumors (NEPT) in the light of the new WHO classification from 2004 and to draw conclusions for future surgical concepts. BACKGROUND: : The extent of surgical resection in primary and recurrent NEPT is unclear. METHODS: Between 1987 and 2004, 62 patients with sporadic NEPT were treated at our institution and sections from biopsy and resection specimen were histopathologically reclassified. Clinical presentation, surgery, metastases, and pattern of recurrence were related to survival. RESULTS: Fifteen well-differentiated tumors (WDT, 24%), 39 low-grade carcinomas (LGC, 63%), and 8 high-grade carcinomas (HGC, 13%) were identified. Median observation time was 30.5 months; 48 of 62 patients (78%) were surgically resected, and in 45 patients R0/R1 status was achieved. Overall 2- and 5-year survival in the latter group was 80% and 64%, respectively. Retrospective WHO classification revealed that organ-preserving segmental resections had been performed in 10 LGC and 1 HGC. These patients showed equal outcome as radically resected counterparts (n = 19). Liver and other organ metastases were present in 19 of 62 patients (31%), and resection was accomplished in 7 of 19 patients, which conferred better overall survival (P = 0.026, log-rank test); 21 of 45 R0/R1-resected patients (47%) suffered from recurrence, and reoperation was accomplished in 9 patients, which resulted in better overall survival (P = 0.066). CONCLUSION: Organ-preserving resections offer sufficient local control in LGC; therefore, radical resections do not seem to be justified. On the other hand, radical resection is indicated even in metastasized patients or in case of loco-regional recurrence. The silent and slow course of the disease facilitates long-term surgical control.

Improvement of impaired microcirculation and tissue oxygenation by hemodilution with hydroxyethyl starch plus cell-free hemoglobin in acute porcine pancreatitis.

AIMS: To avoid the progression from mild edematous acute pancreatitis (AP) to the severe necrotizing form, one therapeutic option is to improve pancreatic microcirculation and tissue oxygenation. The aim of the study was to evaluate the influence of improved rheology (isovolemic hemodilution) plus enhanced oxygen supply (bovine hemoglobin HBOC-301) on pancreatic microcirculation, tissue oxygenation and survival in severe acute experimental pancreatitis. METHODS: Severe AP was induced in 39 pigs (25-30 kg BW) by stimulation with intravenous administration of cerulein plus a pressure- and volume-controlled 10-min intraductal infusion of glycodeoxycholic acid. Seventy-five minutes after induction of AP, animals were randomized and hemodiluted isovolemically (PAOP constant) with either 10% hydroxyethyl starch (HES) 200,000/0.5 plus HBOC-301 (+0.6 g/dl plasmatic hemoglobin; Oxyglobin, Biopure, Cambridge, Mass., USA), or 10% HES 200,000/0.5, or Ringer's solution to a hematocrit of 15%. Hemodynamics, oxygen transport parameters, pancreatic microcirculation and tissue oxygen tension were evaluated over 6 h. Then the abdomen was closed, animals were extubated and observed for 6 days. After that, the surviving animals were sacrificed and specimens were taken from the pancreas. The histopathologic findings were scored by two blinded pathologists who quantified acinar necrosis, fat necrosis, inflammation and edema. RESULTS: Isovolemic hemodilution with HES plus HBOC-301 reduced mortality and preserved pancreatic microcirculation compared with Ringer's solution, but was not significantly different from hemodilution with HES alone. Only treatment with HES plus HBOC-301 normalized pancreatic tissue oxygen tension compared with IHD with HES or Ringer's solution alone. CONCLUSIONS: IHD with HES plus HBOC-301 as a combination of rheologic and O(2)-delivering therapy may represent a novel therapeutic option for treatment of AP.

Microcirculatory function and tissue damage is improved after therapeutic injection of bovine hemoglobin in severe acute rodent pancreatitis.

OBJECTIVES: Stasis of the pancreatic microcirculation initiates and aggravates acute pancreatitis. Bovine hemoglobin has been shown to improve microcirculation in acute pancreatitis if prophylactically infused 15 minutes after initiation of acute pancreatitis. The purpose of this study was to evaluate the therapeutic effectiveness of bovine hemoglobin on pancreatic microcirculation and tissue damage later in the course of experimental acute rodent pancreatitis. METHODS: In Wistar rats, severe acute pancreatitis was induced by administration of glyco-deoxycholic-acid intraductally and cerulein intravenously. Pancreatic microcirculation was continuously monitored by intravital microscopy. Three hours after the initiation of acute pancreatitis, animals received either 0.8 mL bovine hemoglobin (Oxyglobin), hydroxyethyl starch (HES), or 2.4 mL 0.9% NaCl intravenously at random. After 6 hours, animals were killed, and histopathological damage of the pancreas was assessed using a validated histology score. RESULTS: Pancreatic microcirculation assessed by leukocyte adherence was significantly improved by the administration of bovine hemoglobin in comparison with normal saline over time (mean difference, 51.6 +/- 9.2; P < 0.001) and HES (mean difference, 24.1 +/- 9.2; P = 0.037). This result was paralleled by decreased tissue damage in the bovine hemoglobin group as opposed to NaCl (6.75 vs. 12; range, 5.25-7.75 vs. 8.25-14; P < 0.001) and HES (6.75 vs. 9; range, 5.25-7.75 vs. 7.5-10.75; P < 0.001). CONCLUSION: Therapeutic intravenous infusion of bovine hemoglobin improves pancreatic microcirculation and reduces pancreatic tissue damage in severe acute rodent pancreatitis but is not as effective as early (prophylactic) administration.

Systemic intravenous infusion of bovine hemoglobin significantly reduces microcirculatory dysfunction in experimentally induced pancreatitis in the rat.

OBJECTIVE: To evaluate the effectiveness of bovine hemoglobin on pancreatic microcirculation and outcome in experimental acute rodent pancreatitis. SUMMARY BACKGROUND DATA: Stasis of the pancreatic microcirculation initiates and aggravates acute pancreatitis. Hydroxyethyl-starch (HES) has been shown to improve pancreatic microcirculation. Similarly, bovine hemoglobin might improve rheology due to its colloid effect, but additionally supplies oxygen to oxygen depleted pancreatic tissue. METHODS: In Wistar rats, severe acute pancreatitis was induced by administration of glucodeoxycholic acid i.d. and cerulein i.v. Pancreatic microcirculation was continuously monitored by fluorescence microscopy. Fifteen minutes after the initiation of acute pancreatitis, animals received either 0.8 mL bovine hemoglobin (Oxyglobin), HES, or 2.4 mL 0.9% NaCl i.v. at random. After 6 hours, animals were killed and histopathological damage of the pancreas was assessed using a validated histology score (0-16). RESULTS: In comparison to controls, pancreatic microcirculation improved significantly in the HBOC group (mean difference of capillary density 31.4%; standard error 5.6%; P < 0.001; 95% confidence interval for difference 17.5-45.3). HES was not as effective as HBOC substitution. The histology score revealed less tissue damage in the HBOC group [6.25 vs. 9.25 (3-8.5 vs. 8-10.75, P < 0.001)] in comparison to controls and also in comparison to the HES group [6.25 vs. 8 (3-8.5 vs. 6.5-10.25, P < 0.006)]. CONCLUSIONS: In severe acute pancreatitis, single i.v. injection of bovine hemoglobin improves pancreatic microcirculation and reduces tissue damage.