Monitoring of loss of heterozygosity in serum microsatellite DNA among patients with gastrointestinal stromal tumors indicates tumor recurrence.

BACKGROUND: Patients with gastrointestinal stromal tumors (GIST) harbor increased levels of circulating tumor DNA in their peripheral blood. In the current study, the aim was to investigate whether the frequency of loss of heterozygosity (LOH) on cell-free DNA in blood may reflect tumor stage and recurrent disease of these patients. MATERIALS AND METHODS: Serum DNA and follow-up samples of 92 patients suffering from recurrent GIST were analyzed by a PCR-based fluorescence microsatellite analysis using a panel of 12 polymorphic markers. The data were correlated with established risk factors, and patients were followed-up over 4 y. RESULTS: Microsatellite analysis demonstrated a positive LOH score on cell-free DNA of 30/92 patients. A significant correlation with recurrence in CT imaging showed that a positive LOH score (n ≥ 2) was detected in 58% (11/19) of patients with recurrent disease (P = 0.030, χ(2) test), but only in 25% of patients were clinically free of recurrence. No prognostic significance of a positive LOH score was observed after a median observation time of 48 mo. CONCLUSION: Our findings show that LOH on circulating serum DNA correlates with the tumor status and is a frequent event in GIST patients with recurrent disease.

Complementary use of fluorescence and magnetic resonance imaging of metastatic esophageal cancer in a novel orthotopic mouse model.

We describe the development of an aggressive orthotopic metastatic model of esophageal cancer, which is visualized in real time with combined magnetic resonance imaging (MRI) and fluorescence imaging. The aim of the study was to describe the development of a novel model of metastatic tumor disease of esophageal carcinoma and use this model to evaluate fluorescence and MRI in early detection of local and metastatic disease. The human esophageal adenocarcinoma cell line PT1590 was stably transfected with green fluorescent protein (GFP). Nude mice were orthotopically implanted with PT1590-GFP cells. Orthotopic tumor growth as well as metastatic spread was examined by fluorescence imaging and high-resolution MRI at defined intervals after orthotopic implantation. Highly aggressive novel fluorescent cell lines were isolated from metastatic tissues and put into culture. After implantation of these cells, 100% of the animals developed orthotopic primary tumors. In 83% of animals, metastatic spread to liver, lung and lymph nodes was observed. Primary tumor growth could be visualized with fluorescence imaging and with MRI with high correlation between the 2 methods. Fluorescence imaging allows fast, sensitive, and economical imaging of the primary and metastatic tumor without anesthesia. With MRI, anatomical structures are visualized more precisely and tumors can be more accurately localized to specific organs. This model should prove highly useful to understand esophageal carcinoma and to identify novel therapeutics for this treatment-resistant disease.

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.

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.

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.

Nodal microinvolvement in patients with carcinoma of the papilla of vater receiving no adjuvant chemotherapy.

BACKGROUND: To assess the prognostic significance of nodal microinvolvement in patients with carcinoma of the papilla of Vater. METHODS: From 1993 to 2003 at the University Clinic Hamburg, 777 patients were operated upon pancreatic and periampullary carcinomas. The vast majority of patients were operated upon pancreatic ductal adenocarcinoma (n = 566, 73%), followed by carcinomas of the papilla of Vater (n = 112, 14%), pancreatic neuroendocrine carcinomas (n = 39, 5%), intraductal papillary mucinous neoplasms (n = 33, 4%), and distal bile duct carcinomas (n = 27, 3%). Fresh-frozen tissue sections from 169 lymph nodes (LNs) classified as tumor free by routine histopathology from 57 patients with R0 resected carcinoma of the papilla of Vater who had been spared from adjuvant chemotherapy were immunohistochemically (IHC) examined, using a sensitive IHC assay with the anti-epithelial monoclonal antibody Ber-EP4 for tumor cell detection. With regard to histopathology, 39 (63%) of the patients were staged as pT1/pT2, 21 (37%) as pT3/pT4, 30 (53%) as pN0, while 38 (67%) as G1/G2. RESULTS: Of the 169 "tumor-free" LNs, 91 LNs (53.8%) contained Ber-EP4-positive tumor cells. These 91 LNs were from 40 (70%) patients. The mean overall survival in patients without nodal microinvolvement of 35.8 months (median-not yet reached) was significantly longer than that in patients with nodal microinvolvement (mean 16.6; median 13; p = 0.019). Multivariate Cox regression analysis for overall survival revealed that grading was the most significant independent prognostic factor (p = 0.001), followed by nodal microinvolvement (p = 0.013). CONCLUSIONS: The influence of occult tumor cell dissemination in LNs of patients with histologically proven carcinoma of the papilla of Vater supports the need for further tumor staging through immunohistochemistry.

En bloc vascular resection for locally advanced pancreatic malignancies infiltrating major blood vessels: perioperative outcome and long-term survival in 136 patients.

BACKGROUND: To assess in-hospital complication rates and survival duration after en bloc vascular resection (VR) for infiltration of pancreatic malignancies in major vessels. METHODS: Between 1994 and 2005, 585 patients underwent potentially curative pancreatic resection without adjuvant chemotherapy. Four hundred forty-nine patients (77%) underwent standard oncologic resection (VR-), whereas 136 (23%) received VR (VR+). For calculation of in-hospital morbidity and mortality rates, all 136 patients who underwent VR were considered. In contrast, for survival analysis, only pancreatic adenocarcinoma patients (n = 100) were included. RESULTS: One hundred twenty-eight VR+ patients underwent portal or superior mesenteric vein resection and 13 hepatic artery (HA) or superior mesenteric artery (SMA) resection. In 5 patients, synchronous VR addressing both the mesenterico-portal axis and either the HA or SMA was performed. In-hospital morbidity and mortality rates of VR- patients (39.7%/4.0%) nearly equaled that of VR+ patients (40.3%/3.7%). From the 100 patients with pancreatic adenocarcinoma, histopathology confirmed "true" vascular invasion in 77 patients. Twenty-three patients had peritumoral inflammation, mimicking tumor invasion. Median survival was 15 months (11.2-18.8) in patients with histopathologic proven vascular invasion and 16 months (14.0-17.9) in those without (P = 0.86). Two-year survival probabilities were 36% (without) versus 34% (with vascular invasion; P = 0.9). Among VR+ patients with histopathologically evidenced vascular invasion, 19 survived longer than 30 months, and 6 were still alive 5 years after surgery. Multivariate modeling identified nodal involvement (N1) and poor grading (G3) as the only predictors of decreased survival. Evidence of vascular invasion had no adverse impact on survival. CONCLUSION: Postoperative morbidity and mortality rates after en bloc VR are comparable with "standard" pancreatectomy procedures. Median survival of 15 months in patients with vascular invasion is superior to that of patients who undergo palliative therapy and nearly equals that of patients who are not in need for VR.

Short tandem repeat polymorphism in exon 4 of esophageal cancer related gene 2 predicts relapse of oral squamous cell carcinoma.

Short tandem repeat (STR) polymorphisms in exon 4 of esophageal cancer related gene 2 (ECRG2) are a prognostic marker for squamous cell carcinoma (SCC) of the esophagus. The aim of the present study was to correlate these STRs with clinical outcome of the similar tumor type oral squamous cell carcinoma (OSCC). DNA of 81 patients that underwent complete surgical resection of OSCC was analyzed for STRs TCA3/TCA3, TCA3/TCA4 and TCA4/TCA4 in exon 4 of ECRG2 by PCR, capillary electrophoresis and DNA sequencing. ECRG2 STR TCA3/TCA3 were found in 45 (56%), TCA3/TCA4 in 33 (41%) and TCA4/TCA4 in 3 (3%) patients. TCA3/TCA3 was significantly associated with reduced relapse-free survival of OSCC, compared with TCA3/TCA4 and TCA4/TCA4 genotypes (P<0.05; log-rank test). TCA3/TCA3 STR was independent prognostic factor determined by multivariate Cox regression analysis (p<0.05). STR polymorphism TCA3/TCA3 in exon 4 of ECRG2 is associated with poor relapse-free survival in surgically completely resected OSCC patients and might be a potential prognostic marker.

L1 is associated with favorable outcome in neuroblastomas in contrast to adult tumors.

BACKGROUND: Neuroblastoma is the most common solid tumor in childhood with unconventional clinical behavior. L1, a neuronal cell adhesion molecule, is associated with poor survival in malignant adult tumors. The aim of the current study was to determine expression of L1 in pediatric neuroblastoma. METHODS: L1 expression was assessed on a tissue microarray with 66 surgically resected neuroblastoma samples by immunohistochemistry with a monoclonal antibody and peroxidase method. Additionally, mRNA expression was analyzed by reverse transcriptase-polymerase chain reaction with L1-specific primers. Data were correlated survival data by log rank test and Cox regression multivariate analysis. RESULTS: L1 was detected in 57 (86%) of 66 neuroblastomas, whereas 9 (14%) were L1 negative. Median survival of all children was 72 months. Analysis with Kaplan-Meier method revealed a surprising and contrary finding to adult tumor entities: an association of L1 positivity with better event-free and overall survival (P < .001 and P < .01 by log rank test). Multivariate Cox regression analysis showed an independent prognostic impact of L1 negativity for event-free and overall survival of the children (P < .05). CONCLUSIONS: In contrast to adult tumor entities, where L1 is associated with aggressive clinical behavior, our data show that L1 predicts good outcome in children with neuroblastoma. This novel finding suggests an inverse role of L1 in neuroblastoma. Future studies might focus on the molecular basis of the varying effect of L1 in different tumors.

L1 is associated with micrometastatic spread and poor outcome in colorectal cancer.

L1 is a cell adhesion molecule expressed at the invasive front of colorectal tumors with an important role in metastasis. The aim of the present study was to determine L1 protein expression in a large cohort of colorectal cancer patients and its impact on early metastatic spread and survival. A total of 375 patients that underwent surgical treatment for colorectal cancer were chosen retrospectively. A tissue microarray was constructed of 576 tissue samples from these patients and analyzed by immunohistochemistry with a monoclonal antibody against human L1 (UJ127). Lymph node and bone marrow micrometastasis were assessed with monoclonal antibodies Ber-EP4 and pancytokeratin A45-B/B3, respectively. Associations between L1 expression and lymph node, bone marrow micrometastasis and survival were investigated with Fisher's, log-rank test and Cox multivariate analysis. All statistical tests were two-sided. L1 was detected in a subset of 48 (13%) of 375 patients examined. Analysis of L1 expression and survival revealed a significantly worse outcome for L1-positive patients by log-rank test (P<0.05). Multivariate Cox regression analysis showed the strongest independent prognostic impact of L1 expression (P<0.05). Fisher's test revealed a significant association of L1 expression and presence of disseminated tumor cells in lymph nodes and bone marrow (P<0.05). L1 is a powerful prognostic marker for patients that undergo complete surgical resection. It may have a role in early metastatic spread, as L1 is associated with micrometastases to both the lymph nodes and bone marrow. Thus, L1 should be explored further as a target for adjuvant therapy for micrometastatic disease.

Postpancreatectomy hemorrhage: diagnosis and treatment: an analysis in 1669 consecutive pancreatic resections.

BACKGROUND: To analyze clinical courses and outcome of postpancreatectomy hemorrhage (PPH) after major pancreatic surgery. SUMMARY BACKGROUND DATA: Although PPH is the most life-threatening complication following pancreatic surgery, standardized rules for its management do not exist. METHODS: Between 1992 and 2006, 1524 patients operated on for pancreatic diseases were included in a prospective database. A risk stratification of PPH according to the following parameters was performed: severity of PPH classified as mild (drop of hemoglobin concentration <3 g/dL) or severe (>3 g/dL), time of PPH occurrence (early, first to fifth postoperative day; late, after sixth day), coincident pancreatic fistula, intraluminal or extraluminal bleeding manifestation, and presence of "complex" vascular pathologies (erosions, pseudoaneurysms). Success rates of interventional endoscopy and angiography in preventing relaparotomy were analyzed as well as PPH-related overall outcome. RESULTS: Prevalence of PPH was 5.7% (n = 87) distributed almost equally among patients suffering from malignancies, borderline tumors, and focal pancreatitis (n = 47) and from chronic pancreatitis (n = 40). PPH-related overall mortality of 16% (n = 14) was closely associated with 1) the occurrence of pancreatic fistula (13 of 14); 2) vascular pathologies, ie, erosions and pseudoaneurysms (12 of 14); 3) delayed PPH occurrence (14 of 14); and 4) underlying disease with lethal PPH found only in patients with soft texture of the pancreatic remnant, while no patient with chronic pancreatitis died. Conversely, primary severity of PPH (mild vs. severe) and the kind of index operation (Whipple resection, pylorus-preserving partial pancreaticoduodenectomy, organ-preserving procedures) had no influence on outcome of PPH. Endoscopy was successful in 3 from 15 patients (20%), who had intraluminal PPH within the first or second postoperative day. "True," early extraluminal PPH had uniformly to be treated by relaparotomy. Seventeen patients had "false," early extraluminal PPH due to primarily intraluminal bleeding site from the pancreaticoenteric anastomosis with secondary disruption of the anastomosis. From 43 patients subjected to angiography, 25 underwent interventional coiling with a success rate of 80% (n = 20). Overall, relaparotomy was performed in 60 patients among whom 33 underwent surgery as first-line treatment, while 27 were relaparotomied as rescue treatment after failure of interventional endoscopy or radiology. CONCLUSION: Prognosis of PPH depends mainly on the presence of preceding pancreatic fistula. Decision making as to the indication for nonsurgical interventions should consider time of onset, presence of pancreatic fistula, vascular pathologies, and the underlying disease.

Short tandem repeat polymorphism in exon 4 of esophageal cancer-related gene 2 detected in genomic DNA is a prognostic marker for esophageal cancer.

BACKGROUND: Short tandem repeat (STR) polymorphisms in exon 4 of the esophageal cancer-related gene 2 (ECRG2) are a risk marker for esophageal carcinoma. The aim of the present study was to correlate these STRs with clinical outcome. METHODS: Genomic DNA of 86 patients who underwent complete surgical resection was analyzed for STRs TCA3/TCA3, TCA3/TCA4, and TCA4/TCA4 in exon 4 of ECRG2 by polymerase chain reaction and DNA sequencing. RESULTS: ECRG2 STR TCA3/TCA3 and TCA3/TCA4 were found in 40 (47%) patients, respectively, and TCA4/TCA4 in 6 (7%) cases. TCA3/TCA3 genotype was significantly associated with reduced survival (P < .05, log-rank test). TCA3/TCA3 STR was the strongest prognostic factor determined by multivariate Cox regression analysis. CONCLUSIONS: Genetically fixed STR polymorphism TCA3/TCA3 in exon 4 of ECRG2 is associated with poor clinical outcome in surgically treated esophageal cancer patients and might be a potential prognostic marker. The usefulness of these genetic markers to predict responsiveness toward neoadjuvant treatment of esophageal cancer patients would be of high clinical interest and should be examined in future studies.

Thy-1 as a potential novel diagnostic marker for gastrointestinal stromal tumors.

PURPOSE: Only few immunohistochemical markers besides c-kit exist for gastrointestinal stromal tumors (GISTs). Thy-1, a cell-surface glycoprotein, is a marker for several types of stem cells and particularly for neuronal precursor cells. The aim of this study was to determine Thy-1 expression in GISTs. MATERIALS AND METHODS: Fifty-seven surgically resected and paraffin-embedded GIST samples were analyzed by immunohistochemistry with peroxidase method for Thy-1 molecule. RESULTS: Thy-1 was detected in the majority of 57 GIST samples (54 out of 57 patients, 95%). All samples were c-kit positive and 90% were CD34 positive. All three Thy-1 negative samples were CD34 positive, had a low proliferative index (Ki-67

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.

Similar patterns of loss of heterozygosity in serum of adenocarcinoma of the distal oesophagus and the cardia in early diagnosis.

BACKGROUND: Loss of heterozygosity (LOH) may be a valuable tool for detection of malignant proceedings. The aim of our study was to investigate LOH in the serum of patients with adenocarcinoma of the distal oesophagus and the cardia for diagnostic and prognostic utility. PATIENTS AND METHODS: Matched tumour and serum samples from 46 surgically treated patients with oesophageal adenocarcinoma and cardia carcinoma divided in two groups were analysed. Twelve markers were examined with a PCR-based microsatellite analysis. RESULTS: A similar high frequency of LOH (range from 77% to 96%) was detected in the tumour and serum of both groups, whereas no LOH was detected in 20 healthy individuals. However, no significant correlation between LOH incidence and clinicopathological characteristics and survival was found. CONCLUSION: The results indicate that DNA alterations in tumours of the oesophagus and cardia are uniform. The high frequency of LOH in tumour patients underlines the utility of this molecular approach as a diagnostic tool.

Central mesenteric lymph node BER-Ep4+ cells in colorectal cancer: challenge to sentinel node concept?

BACKGROUND: The role of sentinel lymph nodes in colorectal cancer remains unclear. METHODS: Cryosections from central para-aortic mesenterial lymph nodes were stained using mAb BER-Ep4. Overall survival and distant recurrence were calculated using Kaplan-Meier plots. RESULTS: All patients (n = 48) were free of distant metastases and curatively resected (R0). 23 pN0, 13 pN1 and 12 pN2 stages were found. 21/48 patients (44%) showed BER-Ep4+ cells in their central lymph nodes (7/23 pN0, 8/13 pN1, 6/12 pN2). In 6/23 pN0 patients, BER-Ep4+ cells were also found in locoregional nodes (p = 0.03, Fisher's exact test). pN status predicted overall survival (p = 0.006, Kaplan-Meier curve, log-rank test). An impact was exerted by central mesenteric BER-Ep4+ cells on overall survival (p = 0.009 in pN0 patients, p = 0.07 for all pN) and distant recurrence-free survival (p = 0.001 in pN0 patients, p = 0.007 for all pN). Multivariate analysis showed an independent prognostic effect on overall survival in pN0 patients (p = 0.022). CONCLUSION: Central lymph nodes are sentinels of disease not amenable to extended lymphadenectomy and might identify patients at risk of distant organ recurrence.

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.

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.

Frequent homogeneous HER-2 amplification in primary and metastatic adenocarcinoma of the esophagus.

HER-2 is the target for antibody based treatment of breast cancer (Herceptin). In order to evaluate the potential role of such a treatment in esophageal cancers, HER-2 amplification and overexpression was investigated in primary and metastatic cancers of the esophagus. A tissue microarray was constructed from 255 primary esophageal cancers (110 adenocarcinomas and 145 squamous cell carcinomas), 89 nodal and 33 distant metastases. Slides were analyzed by immunohistochemistry (HercepTest; DAKO) and fluorescence in situ hybridization (FISH; PathVysion; Vysis-Abbott) for HER-2 amplification and overexpression. Amplification was seen in 16/110 (15%) adenocarcinomas and in 7/145 (5%) squamous cell carcinomas. There was a strong association between HER-2 amplification and overexpression, especially in adenocarcinomas (P<0.0001, log rank). There was a 100% concordance of the HER-2 results in primary tumor and corresponding metastases in 84 analyzed pairs. Amplification was typically high-level with more than 10-15 HER-2 copies per tumor cell. Amplification was unrelated to survival, grading, pT, pN, pM or UICC stage. We conclude that esophageal adenocarcinomas belong to those cancer types with relevant frequency high-level HER-2 gene amplification clinical trials or individual case studies investigating the response of metastatic HER-2-positive esophageal cancers to Herceptin((R)) should be undertaken. The strong concordance of the HER-2 status in primary and metastatic cancers argues for a possible response of metastases from patients with HER-2-positive primary tumors to Herceptin.

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.