Monosegmental ALPPS: a long-term survival alternative to liver transplant in PRETEXT IV hepatoblastoma.

A 3-year-old female was treated with neoadjuvant chemotherapy (NACT) for a PRETEXT IV hepatoblastoma. POST-TEXT IV findings merited a liver transplant (LT), but multiple limitations precluded it. The initial future liver remnant (FLR) was small (21.3%). Monosegment 6 ALPPS was a rational approach given that the inferior right hepatic vein (IRHV) provided adequate outflow. Therefore, the procedure was performed after parental informed consent. On PO15 of the first stage, FLR had reached 32.6% and then the second-stage was carried out. The patient was discharged on POD 31, and she is about to reach the 5-year disease-free survival milestone.

Overexpression of protein phosphatase 4 correlates with poor prognosis in patients with stage II pancreatic ductal adenocarcinoma.

PURPOSE: Protein phosphatase 4 (PP4) has been reported to be overexpressed in breast and lung cancers. PP4 plays an important role in the regulation of centrosome maturation, DNA repair, NF-κB, and c-jun-NH(2)-kinase (JNK) signaling pathways. However, the expression and functions of PP4 in pancreatic cancer have not been studied. EXPERIMENTAL DESIGN: We examined the expression of PP4 catalytic subunit (PP4C) protein in 133 patients with stage II pancreatic ductal adenocarcinoma (PDAC) and their paired benign pancreatic samples (N = 113) by immunohistochemistry. To confirm the immunohistochemical results, we measured PP4C protein and mRNA levels by Western blotting and real-time reverse transcriptase PCR. Using univariate and multivariate analysis, we correlated PP4C expression with survival and other clinicopathologic features. RESULTS: PP4C was overexpressed in 75 of 133 (56.4%) stage II PDAC samples, which was significantly higher than the paired benign pancreatic tissue (15%, 17 of 113). PP4C mRNA expression levels were also higher in PDAC samples than the paired benign pancreatic tissue. Overexpression of PP4C in PDAC samples was associated with higher frequencies of distant metastasis (P = 0.02) and poor disease-free and overall survivals in patients with stage II PDAC (P = 0.006 and 0.02) independent of tumor size, margin status, and lymph node status (stage). CONCLUSIONS: Our study showed that PP4C is overexpressed in PDAC. Overexpression of PP4C in PDAC samples is associated with poor prognosis in patients with stage II PDAC. Therefore, targeting PP4 signaling pathway may represent a new approach for the treatment of PDAC. IMPACT: Our study showed that PP4C is an independent prognostic factor in patients with stage II PDAC.

Tumor invasion of muscular vessels predicts poor prognosis in patients with pancreatic ductal adenocarcinoma who have received neoadjuvant therapy and pancreaticoduodenectomy.

Lymphovascular invasion (LVI) is a prognostic factor in many types of human malignancies, including pancreatic ductal adenocarcinoma (PDAC). However, the prognostic significance of LVI in patients with PDAC who have received neoadjuvant therapy and pancreaticoduodenectomy is unclear. In this study, we analyzed LVI in 212 patients who had received neoadjuvant chemoradiation and subsequent pancreaticoduodenectomy at our institution between January 1999 and December 2007. LVI was present in 61.8% (131/212) of the patients. Of the 131 patients who were positive for LVI, 67 (31.6%) had tumor invasion into lymphovascular spaces without muscle layer (nonmuscular lymphovascular spaces), and 64 (30.2%) had tumor invasion into muscular vessels. Tumor invasion into muscular vessels correlated with higher frequencies of positive resection margin, lymph node metastasis, and locoregional/distant recurrence. Patients with tumor invasion into muscular vessels had significantly shorter disease-free survival and overall survival than did patients who had no LVI or who had tumor invasion of nonmuscular lymphovascular spaces (P<0.01). Tumor invasion into muscular vessels is an independent prognostic factor in patients with PDAC who have received neoadjuvant therapies. Our results showed that tumor invasion into muscular vessels plays an important role in the progression of PDAC and in predicting prognosis in this group of patients.

Perineural and intraneural invasion in posttherapy pancreaticoduodenectomy specimens predicts poor prognosis in patients with pancreatic ductal adenocarcinoma.

Perineural invasion (PNI) is one of the established prognostic factors in pancreatic ductal adenocarcinoma (PDAC). However, the prognostic significance of PNI in patients with PDAC who received neoadjuvant therapy and pancreaticoduodenectomy is not clear. In this study, we performed a detailed examination of neural invasion in pancreaticoduodenectomy specimens from 212 patients with PDAC who received neoadjuvant chemoradiation (treated group) and in 60 untreated patients at our institution between January 1999 and December 2007. The frequency of PNI was higher in the untreated group (80%, 48/60) than in the treated group (58%, 123/212). For the 123 treated cases that were positive for PNI, extratumoral PNI, intratumoral PNI, intrapancreatic PNI only, extrapancreatic PNI, and intraneural invasion were identified in 86 (69.9%), 37 (30.1%), 11 (8.9%), 112 (91.1%), and 35 cases (28.5%), respectively. The presence of PNI correlated with tumor size, margin status, lymph node metastasis, pathologic tumor, and American Joint Committee on Cancer stages in the treated group. Tumor involvement of nerves >0.8 mm correlated with higher frequency of positive margin compared with tumors with PNI involving nerves ≤0.8 mm but not with other clinicopathologic parameters and survival. In the treated group, the presence of PNI or intraneural invasion correlated significantly with shorter disease-free survival and overall survival compared with no PNI or PNI only, respectively. PNI was an independent prognostic factor for both disease-free survival and overall survival in multivariate analysis. Our results showed that PNI plays an important role in the progression of PDAC and in predicting prognosis in this group of patients.

Outcomes and economic analysis of routine preoperative 4-dimensional CT for surgical intervention in de novo primary hyperparathyroidism: does clinical benefit justify the cost?

BACKGROUND: Preoperative imaging in patients with primary hyperparathyroidism provides important localization information. Although 4-dimensional neck CT (4DCT) can precisely localize hyperfunctioning parathyroid tissue, the contribution of 4DCT to overall cost, operating room time, and hospital stay is unknown. STUDY DESIGN: Records of 535 patients with primary hyperparathyroidism who underwent parathyroidectomy at our institution from 1996 to 2010 were reviewed. All patients had preoperative cervical ultrasonography and sestamibi scanning, and most (78.9%) underwent preoperative 4DCT. A decision tree was constructed to compare extent of procedure, operating room time, length of stay, failure rate, and total cost of each strategy (with and without 4DCT). Costs were determined by 2010 Medicare reimbursement. RESULTS: For patients with and without preoperative 4DCT, respectively, mean operating room time (64.4 vs 61.4 minutes; p = 0.58) and failure rate (1.9% vs 4.4%; p = 0.12) were not significantly different. Length of stay was higher in the no-CT cohort (0.61 vs 0.23 days; p < 0.001). Patients with a preoperative 4DCT were significantly more likely to undergo a limited parathyroidectomy (90.3% vs 80.5%; p = 0.004). Mean cost of care per patient in the CT and no-CT cohorts was $6,572 and $6,306, respectively. CONCLUSIONS: The introduction of routine 4DCT into the preoperative workup for surgical intervention in primary hyperparathyroidism does not appear to shorten operating room time or decrease failure rate significantly. However, preoperative 4DCT is associated with shorter hospital stays and improved rates of minimally invasive parathyroidectomy. This clinical benefit must be weighed against the increased cost associated with routine preoperative 4DCT.

Histologic tumor involvement of superior mesenteric vein/portal vein predicts poor prognosis in patients with stage II pancreatic adenocarcinoma treated with neoadjuvant chemoradiation.

BACKGROUND: Studies have shown that superior mesenteric vein (SMV)/portal vein (PV) resection with pancreaticoduodenectomy (PD) is safe and feasible for patient with pancreatic adenocarcinoma (PAC). However, the prognostic significance of tumor involvement of the resected vein in patients who received neoadjuvant therapy is unclear. METHODS: The authors evaluated 225 consecutive patients with stage II PAC who received neoadjuvant therapy and PD with or without SMV/PV resection. The resected SMV/PV was entirely submitted for histologic assessment and reviewed in all cases. Tumor involvement of the SMV/PV was correlated with clinicopathologic features and survival. RESULTS: Among the 225 patients, SMV/PV resection was performed in 85 patients. Histologic tumor involvement of the resected SMV/PV was identified in 57 patients. Histologic tumor involvement of the SMV/PV was associated with larger tumor size, higher rates of positive margin, and local/distant recurrence. By multivariate analysis, tumor involvement of the SMV/PV was an independent predictor of both disease-free survival (DFS) and overall survival (OS). However, addition of venous resection to PD itself had no impact on either DFS or OS compared with those with PD alone. CONCLUSIONS: Histologic tumor involvement of the SMV/PV is an independent predictor of both DFS and OS in patients with stage II PAC treated with neoadjuvant therapy and PD. Complete histologic evaluation of the resected SMV/PV is important for the prognosis in patients with PAC who received neoadjuvant therapy and PD.

Post-therapy pathologic stage and survival in patients with pancreatic ductal adenocarcinoma treated with neoadjuvant chemoradiation.

BACKGROUND: Neoadjuvant chemoradiation before surgery is an emerging treatment modality for pancreatic ductal adenocarcinoma (PDAC). However, analysis of prognostic factors is limited for patients with PDAC treated with neoadjuvant chemoradiation and pancreaticoduodenectomy (PD). METHODS: The study population was comprised of 240 consecutive patients with PDAC who received neoadjuvant chemoradiation and PD and was compared with 60 patients who had no neoadjuvant therapy between 1999 and 2007. Clinicopathologic features were correlated with disease-free survival (DFS) and overall survival (OS). RESULTS: Among the 240 treated patients, the 1-year and 3-year DFS rates were 52% and 32%, with a median DFS of 15.1 months. The 1-year and 3-year OS rates were 95% and 47%, with a median OS of 33.5 months. By univariate analysis, DFS was associated with age, post-therapy tumor stage (ypT), lymph node status (ypN), number of positive lymph nodes, and American Joint Committee on Cancer (AJCC) stage, whereas OS was associated with intraoperative blood loss, margin status, ypT, ypN, number of positive lymph nodes, and AJCC stage. By multivariate analysis, DFS was independently associated with age, number of positive lymph nodes, and AJCC stage, and OS was independently associated with differentiation, margin status, number of positive lymph nodes, and AJCC stage. In addition, the treated patients had better OS and lower frequency of lymph node metastasis than those who had no neoadjuvant therapy. CONCLUSIONS: In patients with PDAC who received neoadjuvant chemoradiation and subsequent PD, post-therapy pathologic AJCC stage and number of positive lymph nodes are independent prognostic factors.

Pathologic complete response to neoadjuvant therapy in patients with pancreatic ductal adenocarcinoma is associated with a better prognosis.

In patients with pancreatic ductal adenocarcinoma (PDA) who received neoadjuvant therapy and pancreatectomy, pathologic complete response (pCR) is rarely observed and the prognostic significance of pCR is not clear. In this study, we identified 11 patients with pCR (2.5%) from 442 patients with PDA who received neoadjuvant treatment and pancreatectomy from 1995 to 2010. There were 6 men and 5 women, with a median age of 61 years. Four patients had either synchronous or history of extrapancreatic cancer. Five patients received neoadjuvant chemotherapy followed by chemoradiation, and 6 received chemoradiation alone. Ten patients had pancreaticoduodenectomy, and 1 had distal pancreatectomy. Scar and chronic pancreatitis consistent with therapy effect were present in all cases (100%). Pancreatic intraepithelial neoplasia (PanIN) 3/carcinoma in situ was present in 5 cases, and PanIN1 and PanIN2 in 5 cases. However, no residual invasive carcinoma or lymph node metastasis was identified in all cases. Follow-up information was available in 10 patients. Follow-up time ranges from 6 to 194 months (median, 63 months). During the follow-up, 3 patients died of other causes, and 1 developed a second primary PDA in the tail of the pancreas at 84 months after the initial pancreaticoduodenectomy and died at 105 months after the initial diagnosis of PDA. The other 6 patients were alive with no evidence of disease. Patients with pCR had a better survival than did those who had posttherapy stage I or IIA disease (P < .001). Patients with PDA who received neoadjuvant therapy and had pCR in pancreatectomy are rare but have a better prognosis.

Histologic grading of the extent of residual carcinoma following neoadjuvant chemoradiation in pancreatic ductal adenocarcinoma: a predictor for patient outcome.

BACKGROUND: Several grading schemes for the extent of residual tumor in posttreatment pancreaticoduodenectomy (PD) specimens have been proposed. However, the prognostic significance of these grading schemes is unknown. METHODS: Histopathologic slides of 223 cases who received neoadjuvant chemoradiation and PD were reviewed. The extent of residual tumor was graded using both the College of American Pathologists (CAP) and the Evans grading systems. The grading results were correlated with clinicopathological parameters and survival. RESULTS: Among the 223 patients, 6 patients (2.7%) showed pathologic complete response (pCR; CAP grade 0 or Evans grade IV), 36 cases (16.1%) had minimal residual tumor (CAP grade 1 or Evans grade III), 124 cases (55.6%) had moderate response (CAP grade 2 or Evans grade IIb), and 57 cases (25.6%) had poor response (CAP grade 3, where 18 had Evans grade I and 39 had Evans grade IIa response). Patients with pCR or minimal residual tumor (response group 1) had better survival rates than those with moderate and poor response (response group 2). Response group 1 patients had lower posttherapy tumor and American Joint Committee on Cancer stages and lower rates of lymph node metastasis, positive resection margin, and recurrence and/or metastasis. Grading the extent of residual tumor is an independent prognostic factor for overall survival in multivariate analysis. CONCLUSIONS: pCR or minimal residual tumor in posttreatment PD specimens correlate with better survival in patients with pancreatic ductal adenocarcinoma who received neoadjuvant therapy and PD. Histologic grading of the extent of residual tumor in PD specimen is an important prognostic factor in patients with pancreatic ductal adenocarcinoma who received neoadjuvant therapies.

Overexpression of receptor tyrosine kinase Axl promotes tumor cell invasion and survival in pancreatic ductal adenocarcinoma.

BACKGROUND: The receptor tyrosine kinase Axl has been reported to be overexpressed in a variety of human cancers. Although previous studies have identified the role of Axl in the transformation, proliferation, survival, and invasion in cancers, the expression and functions of Axl in pancreatic cancer have not been studied in detail. METHODS: The expression of Axl protein in 12 pancreatic cancer cell lines and 54 patient samples of stage II pancreatic ductal adenocarcinoma (PDA) and their paired non-neoplastic pancreatic tissue samples were examined. Using univariate and multivariate analysis, Axl expression was correlated with survival and other clinicopathologic features. To examine Axl functions in PDA, the effects of Axl knockdown on the invasion ability and radiation-induced apoptosis in PDA cell lines were measured. RESULTS: Axl was overexpressed in 38 of 54 (70%) stage II PDA samples and 9 of 12 (75%) PDA cell lines. Axl overexpression was associated with higher frequencies of distant metastasis and poor overall and recurrence-free survivals (P = .03 and P = .04, respectively) independent of tumor size and stage or lymph node status in patients with stage II PDA. Knockdown of Axl expression in PDA cells abolished Gas6-mediated Akt activation, decreased invasion, and increased radiation-induced PARP cleavage and the percentage of apoptosis. CONCLUSIONS: This study showed that Gas6 and Axl are frequently overexpressed in PDA cells and are associated with a poor prognosis in patients with stage II PDA. Axl promotes the invasion and survival of PDA cells. Therefore, targeting the Axl signaling pathway may represent a new approach to the treatment of PDA.

High levels of expression of human stromal cell-derived factor-1 are associated with worse prognosis in patients with stage II pancreatic ductal adenocarcinoma.

BACKGROUND: Stromal cell-derived factor-1 (SDF-1) and its receptor, CXCR4, have been shown to mediate invasiveness and metastatic behavior in a number of cancers, including ovarian, prostate, bladder, breast, and pancreatic cancers. The expression and significance of SDF-1 in pancreatic ductal adenocarcinoma (PDA) have not been systematically studied. METHODS: We examined the expression of SDF-1 by immunohistochemistry using a mouse anti-human SDF-1/CXCL12 antibody (dilution 1:300) and a tissue microarray consisting of 72 stage II PDAs from pancreaticoduodenectomy specimens. The staining results were categorized as SDF-1-high (SDF-1-H; cytoplasmic staining of ≥10% of tumor cells) or SDF-1-low (SDF-1-L; no staining or staining of <10% of tumor cells). The results of SDF-1 expression were correlated with clinicopathologic parameters and survival. Statistical analyses were done using SPSS software. RESULT: Of the 72 stage II PDAs, 25 (35%) showed high levels of SDF-1 expression. The median overall and recurrence-free survival for patients with SDF-1-H PDAs were 26.1 and 11.1 months, respectively, compared with 44.3 and 22.3 months for patients with SDF-1-L tumors (log-rank test, P = 0.047 and P = 0.021). In multivariate analysis, high SDF-1 expression correlated with poor overall and disease-free survival (P = 0.02 and P = 0.02) independent of tumor size, differentiation, and lymph node status. CONCLUSION: High levels of SDF-1 expression were associated with poor overall and disease-free survival in patients with stage II PDA. SDF-1 may serve as a useful prognostic marker for stage II PDA. IMPACT: Our results suggest that SDF-1-CXCR4 or SDF-1-CXCR7 pathways may represent a potential target for therapeutic intervention as well as prediction of prognosis in PDA.

High levels of nucleolar expression of nucleolin are associated with better prognosis in patients with stage II pancreatic ductal adenocarcinoma.

PURPOSE: Nucleolin is a major nucleolar protein that has been shown to be overexpressed in rapidly dividing cells and plays an essential role in cell proliferation and survival. However, the expression and significance of nucleolin in pancreatic ductal adenocarcinoma (PDA) have not been studied. EXPERIMENTAL DESIGN: We used a tissue microarray consisting of 1.0-mm cores of tumor and paired nonneoplastic pancreatic tissue from 69 pancreaticoduodenectomy specimens with stage II PDA. Nucleolin expression was evaluated by immunohistochemistry and scored quantitatively by image analysis. Nucleolin expression was classified as nucleolin-high or nucleolin-low using the median nucleolin labeling index of 3.5% as cutoff. Staining results were correlated with clinicopathologic features and survival. RESULTS: Both PDAs and PDA cell lines showed nucleolar staining for nucleolin. Nucleolin expression was higher in PDAs and PDA cell lines than in nonneoplastic ductal epithelial cells. Among the 69 stage II PDAs, 34 (49%) were nucleolin-high. The median overall survival was 65.2 +/- 16.3 months for patients who had nucleolin-high PDAs compared with 19.5 +/- 3.3 months for patients whose tumors were nucleolin-low (P = 0.03, log-rank method). No significant correlation between nucleolin expression and other clinicopathologic parameters was found. In multivariate analysis, nucleolin expression was a prognostic factor for overall survival in patients with stage II PDA independent of patient's age, gender, tumor size, differentiation, and lymph node status. CONCLUSIONS: Nucleolin was overexpressed in PDAs and PDA cell lines. A high level of nucleolar expression of nucleolin was an independent prognostic marker for better survival for patients with stage II PDAs.

The learning curve in pancreatic surgery.

BACKGROUND: Pancreatic surgery is technically complex. We hypothesized that a learning curve existed for pancreaticoduodenectomy even for surgeons who had completed their training. METHODS: During 1990 to 2004, we studied 650 consecutive patients who underwent pancreaticoduodenectomy by 3 surgeons who began their attending careers at 1 center. Operative time, estimated blood loss (EBL), length of hospital stay (LOS), and the status of resection margins (for pancreatic adenocarcinoma) were analyzed. The chi2, independent t test and Mann-Whitney U test were used to evaluate differences in categorical, normally distributed continuous, and non-normally distributed continuous variables, respectively. Using serial groups of 30 cases, median operative time, EBL, and LOS were calculated and the trend over time modeled using third-order polynomial equations. Trends in retroperitoneal margin positivity (R0/R1) were assessed. RESULTS: From the first 60 cases per surgeon to the second 60 cases per surgeon, the median EBL dropped (1100 vs 725 mL, P < .001), operative time decreased (589 vs 513 minutes, P < .001), and LOS decreased (15 vs 13 days, P = .004). The proportion of microscopically positive or suspicious margins also decreased from the surgeons' first 60 cases each to the second 60 cases (30% vs 8%, P < .001). Extended analysis of a single surgeon's cases suggested that additional experience provided further incremental improvement (P < .001). CONCLUSIONS: Pancreaticoduodenectomy has an inherent learning curve. After 60 cases, surgeons achieved significantly decreased EBL, operative time, and LOS, and carried out more margin-negative resections. Improvement in measured outcomes continues during the operative career.

The learning curve in pancreatic surgery.

BACKGROUND: Pancreatic operation is technically complex. We hypothesized that a learning curve existed for pancreaticoduodenectomy even for surgeons who had completed their training. METHODS: During 1990 to 2004, we studied 650 consecutive patients who underwent pancreaticoduodenectomy by 3 surgeons who began their attending careers at 1 center. Operative time, estimated blood loss (EBL), length of hospital stay (LOS), and the status of resection margins (for pancreatic adenocarcinoma) were analyzed. The chi(2), independent t test and Mann-Whitney U test were used to evaluate differences in categoric, normally distributed continuous, and non-normally distributed continuous variables, respectively. Using serial groups of 30 cases, median operative time, EBL, and LOS were calculated and the trend over time modeled using third-order polynomial equations. Trends in retroperitoneal margin positivity (R0/R1) were assessed. RESULTS: From the first 60 cases per surgeon to the second 60 cases per surgeon, the median EBL dropped (1100 vs 725 mL, P < .001), operative time decreased (589 vs 513 minutes, P < .001), and LOS decreased (15 vs 13 days, P = .004). The proportion of microscopically positive or suspicious margins also decreased from the surgeons' first 60 cases each to the second 60 cases (30% vs 8%, P < .001). Extended analysis of a single surgeon's cases suggested that additional experience provided further incremental improvement (P < .001). CONCLUSIONS: Pancreaticoduodenectomy has an inherent learning curve. After 60 cases, surgeons achieved significantly decreased EBL, operative time, and LOS, and carried out more margin-negative resections. Improvement in measured outcomes continues during the operative career.

Pancreaticoduodenectomy after placement of endobiliary metal stents.

Contemporary treatment programs for patients with potentially resectable pancreatic cancer often involve preoperative therapy. When the duration of preoperative therapy exceeds 2 months, the risk of plastic endobiliary stent occlusion increases. Metal stents have much better patency but may complicate subsequent pancreaticoduodenectomy (PD). We evaluated rates of perioperative morbidity, mortality, and stent complications in 272 consecutive patients who underwent PD at our institution from May 2001 to November 2004. Of these 272 patients, 29 (11%) underwent PD after placement of a metal stent, 141 underwent PD after placement of a plastic stent, 10 had PD after biliary bypass without stenting, and 92 had PD without any form of biliary decompression. No differences were found between the Metal Stent group and all other patients in median operative time, intraoperative blood loss, or length of hospital stay. No perioperative deaths occurred in the Metal Stent group versus 3 (1.2%) deaths in the other 243 patients. The incidence of major perioperative complications was similar between the two groups, including the rates of pancreatic fistula, intra-abdominal abscess, and wound infection. Furthermore, there were no differences in the perioperative morbidity or mortality rates between patients who underwent preoperative biliary decompression with a stent of any kind (metal or plastic) and those patients who underwent no biliary decompression at all. Metal stent-related complications occurred in 2 (7%) of 29 patients during a median preoperative interval of 4.1 months; in contrast, 75 (45%) of the 166 patients who had had plastic stents experienced complications, including 98 stent occlusions, during a median preoperative interval of 3.9 months (P < 0.001). We conclude that the use of expandable metal stents does not increase PD-associated perioperative morbidity or mortality, and as such an expandable metal stent is our preferred method of biliary decompression in patients with symptomatic malignant distal bile duct obstruction in whom surgery is not anticipated, or in whom there is a significant delay in the time to surgery.

Pancreaticoduodenectomy with vascular resection: margin status and survival duration.

Major vascular resection performed at the time of pancreaticoduodenectomy (PD) for adenocarcinoma remains controversial. We analyzed all patients who underwent vascular resection (VR) at the time of PD for any histology at a single institution between 1990 and 2002. Preoperative imaging criteria for PD included the absence of tumor extension to the celiac axis or superior mesenteric artery (SMA). Tangential or segmental resection of the superior mesenteric or portal veins was performed when the tumor could not be separated from the vein. As a separate analysis, all patients who underwent PD with VR for pancreatic adenocarcinoma were compared to all patients who underwent standard PD for pancreatic adenocarcinoma. A total of 141 patients underwent VR with PD. Superior mesenteric-portal vein resections included tangential resection with vein patch (n=36), segmental resection with primary anastomosis (n=35), and segmental resection with autologous interposition graft (n=55). Hepatic arterial resections were performed in 10 patients, and resections of the anterior surface of the inferior vena cava were performed in 5 patients. PD was performed for pancreatic adenocarcinoma in 291 patients; standard PD was performed in 181 and VR in 110. Median survival was 23.4 months in the group that required VR and 26.5 months in the group that underwent standard PD (P=0.177). A Cox proportional hazards model was constructed to analyze the effects of potential prognostic factors (VR, tumor size, T stage, N status, margin status) on survival. The need for VR had no impact on survival duration. In conclusion, properly selected patients with adenocarcinoma of the pancreatic head who require VR have a median survival of approximately 2 years, which does not differ from those who undergo standard PD and is superior to historical patients believed to have locally advanced disease treated nonoperatively.

Lactoferrin impairs type III secretory system function in enteropathogenic Escherichia coli.

Enteropathogenic Escherichia coli (EPEC) is an important cause of infant diarrhea in developing countries. EPEC uses a type III secretory system to deliver effector proteins into the host cell. These proteins cause the characteristic attaching and effacing lesion on enterocytes. Lactoferrin, a glycoprotein present in human milk, inhibits EPEC adherence to mammalian cells. To determine the effect of lactoferrin on the initial host cell attachment step that is mediated by the type III secretory system, we focused on EPEC-induced actin polymerization in HEp2 cells, on the hemolytic activity, and on measurement of E. coli secreted proteins A, B, and D (EspABD). Lactoferrin blocked EPEC-mediated actin polymerization in HEp2 cells and blocked EPEC-induced hemolysis. The mechanism of this inhibition was lactoferrin-mediated degradation of secreted proteins necessary for bacterial contact and pore formation, particularly EspB. The proteolytic effect of lactoferrin was prevented by serine protease inhibitors. This disruption of the type III secretory system implies that lactoferrin could provide broad cross protection against the enteropathogens that share this mechanism.

Human milk secretory antibodies against attaching and effacing Escherichia coli antigens.

Secretory immunoglobulin A (sIgA) is a primary factor responsible for preventing attachment of enteropathogens to gut epithelium in breastfeeding infants. We compared the frequency of sIgA to major surface antigens of enterohemorrhagic Escherichia coli (EHEC) in milk of 123 women from the United States and Mexico to determine whether regional differences existed in the frequency of antibodies to these surface antigens. In both groups of women, milk commonly has sIgA against various EHEC lipopolysaccharides, EspA, EspB, intimin, and less frequently against Shiga toxin. The study suggests that persons living in the United States are exposed to attaching/effacing enteropathogens more frequently than is generally assumed. The low frequency of antibodies to Stx1 (in 12% of Mexican and in 22% of U.S. samples) suggests that the rare appearance of hemolytic uremic syndrome in adults is not due to neutralization of toxin at the gut level. Only anti-EspA is found in most milk samples from both populations of women. EspA may represent a useful target for an immunization strategy to prevent EHEC disease in humans.

Human lactoferrin impairs virulence of Shigella flexneri.

Lactoferrin is a glycoprotein present in most human mucosal secretions, including human milk. Lactoferrin is bacteriostatic in low iron media and, in some settings, bactericidal. Lactoferrin impairs ability of Shigella flexneri serotype 5 strain M90T to invade HeLa cells. To determine the mechanism by which lactoferrin decreases invasiveness of Shigella organisms, its effect on the major virulence proteins responsible for bacterial uptake by host cells was evaluated. Lactoferrin induced degradation of invasion plasmid antigens IpaB and, to a lesser extent, IpaC, the key proteins responsible for bacteria-directed phagocytosis by mammalian cells. The lipid A-binding N-terminal portion of lactoferrin (residues 1-33) induces release of invasion antigens but does not induce degradation of IpaBC. Lactoferrin does not directly degrade previously released invasion plasmid antigens but works by making IpaBC susceptible to breakdown by surface-expressed protease(s).

Lactoferrin protects rabbits from Shigella flexneri-induced inflammatory enteritis.

Shigella species cause bacillary dysentery in humans by invasion, intracellular multiplication, spread to adjacent cells, and induction of brisk inflammatory responses in the intestinal epithelium. In vitro data suggest that lactoferrin, a glycoprotein present in human mucosal secretions, has a role in protection from bacterial enteric infections. We sought to determine the activity of lactoferrin in vivo, using the concentration present in human colostrum, to investigate its effect on the development of clinical and pathological evidence of inflammation in a rabbit model of enteritis. Lactoferrin protected rabbits infected with Shigella flexneri from developing inflammatory intestinal disease. Typical histological changes in ill animals included villous blunting with sloughing of epithelial cells, submucosal edema, infiltration of leukocytes, venous congestion, and hemorrhage. Lactoferrin at a concentration normally found in human colostrum blocks development of S. flexneri-induced inflammatory enteritis.