Oncological problems in pancreatic cancer surgery

Development of [225Ac]Ac-DOTA-C595 as radioimmunotherapy of pancreatic cancer: in vitro evaluation, dosimetric assessment and detector calibration

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive malignancy which may benefit from radioimmunotherapy. Previously, [177Lu]Lu-DOTA-C595 has been developed as a beta-emitting radioimmunoconjugate to target cancer-specific mucin 1 epitopes (MUC1-CE) overexpressed on PDAC. However, the therapeutic effect may be enhanced by using an alpha-emitting radionuclide such as Actinium-225 (Ac-225). The short range and high linear energy transfer of alpha particles provides dense cellular damage and can overcome typical barriers related to PDAC treatment such as hypoxia. Despite the added cytotoxicity of alpha-emitters, their clinical implementation can be complicated by their complex decay chains, recoil energy and short-range impeding radiation detection. In this study, we developed and evaluated [225Ac]Ac-DOTA-C595 as an alpha-emitting radioimmunotherapy against PDAC using a series of in vitro experiments and conducted a preliminary dosimetric assessment and cross-calibration of detectors for the clinical implementation of Ac-225.

RESULTS

Cell binding and internalisation of [225Ac]Ac-DOTA-C595 was rapid and greatest in cells with strong MUC1-CE expression. Over 99% of PDAC cells had positive yH2AX expression within 1 h of [225Ac]Ac-DOTA-C595 exposure, suggesting a high level of DNA damage. Clonogenic assays further illustrated the cytotoxicity of [225Ac]Ac-DOTA-C595 in a concentration-dependent manner. At low concentrations of [225Ac]Ac-DOTA-C595, cells with strong MUC1-CE expression had lower cell survival than cells with weak MUC1-CE expression, yet survival was similar between cell lines at high concentrations irrespective of MUC1-CE expression. A dosimetric assessment was performed to estimate the dose-rate of 1 kBq of [225Ac]Ac-DOTA-C595 with consideration to alpha particles. Total absorption of 1 kBq of Ac-225 was estimated to provide a dose rate of 17.5 mGy/h, confirmed via both detector measurements and calculations.

CONCLUSION

[225Ac]Ac-DOTA-C595 was shown to target and induce a therapeutic effect in MUC1-CE expressing PDAC cells.

Long Term Outcomes of No-Touch Isolation Principles Applied in Pancreaticoduodenectomy for Treatment of Pancreatic Adenocarcinoma: A Multicenter Retrospective Study with Propensity Score Matching

Background: The recurrence and liver metastasis rates are still high in pancreatic head cancer with curative surgical resection. A no-touch isolation principle in pancreaticoduodenectomy (PD) may improve this situation, however, the exact advantages and efficacy of these principles have not been confirmed. Materials and methods: Among 370 patients who underwent PD, three centers were selected and classified into two groups: the no-touch PD group (n = 70) and the conventional PD group (n = 300). Propensity score matching was used to control for selection bias at a ratio of 1:1. The confounding variables were age, sex, body mass index, adjuvant chemotherapy, carbohydrate antigen 19-9, tumor size and tumor differentiation. Results: Patients in the no-touch PD group had better overall survival (OS) and disease-free survival (DFS) than those in the conventional PD group (OS: 17 vs. 13 months, p = 0.0035, DFS: 15 vs. 12 months, p = 0.087), with lower 1- and 2-year disease-related mortality rates (1-year: 32.9% vs. 47%, p = 0.032; 2-year: 42.5% vs. 82% p = 0.000) and recurrence and liver metastasis rates (1-year: 30.0% vs. 43.3%, p = 0.041; 2-year: 34.3% vs. 48.7%, p = 0.030). Compared with the matched conventional PD group, the no-touch PD group also had a better OS (17 vs. 12 months, p = 0.032). Conclusions: Our study showed the no-touch isolation principle may be a better choice to improve long-term survival for pancreatic cancer patients.

High SUVmax on routine pre-operative FDG-PET predicts early recurrence in pancreatic and peri-ampullary cancer

BACKGROUND

SUVmax of a primary pancreatic tumour on FDG-PET/CT (SUVmax-p) may predict early post-operative recurrence. This has not been tested in the context of routine pre-operative FDG-PET/CT. It is also unknown whether this association exists independent of local residual tumour.

METHODS

FDG-PET/CT was performed routinely prior to resection of pancreatic or peri-ampullary adenocarcinoma between 2008 and 2012 as part of a previous prospective study. We compared SUVmax-p according to whether recurrence was diagnosed within 6 months of resection. We also determined the odds ratio for recurrence within 6 months for multiple cut-points of SUVmax-p. This analysis was repeated exclusively for patients who had resection with clear surgical margins (R0).

RESULTS

Of 56 patients from the initial study 23 underwent resection and were eligible. Recurrence within 6 months was associated with higher median SUVmax-p (5.9 vs 3.5; p = 0.04). This was also observed in 12 patients who underwent R0 resection (6.5 vs 2.2; p = 0.05). The cut-point with the highest odds for recurrence within 6 months for both groups was SUVmax-p ≥ 5.5 (OR = 10.8, CI = 1.56-109; OR[R0] = 24.0, CI = 1.64-1020).

CONCLUSION

SUVmax-p on routine FDG-PET/CT is useful for identifying patients likely to benefit from additional pre-operative staging or neoadjuvant therapy, even where clear margins can confidently be achieved.

In Vitro Tumor Cell-Binding Assay to Select High-Binding Antibody and Predict Therapy Response for Personalized 64Cu-Intraperitoneal Radioimmunotherapy against Peritoneal Dissemination of Pancreatic Cancer: A Feasibility Study

Peritoneal dissemination of pancreatic cancer has a poor prognosis. We have reported that intraperitoneal radioimmunotherapy using a 64Cu-labeled antibody (64Cu-ipRIT) is a promising adjuvant therapy option to prevent this complication. To achieve personalized 64Cu-ipRIT, we developed a new in vitro tumor cell-binding assay (64Cu-TuBA) system with a panel containing nine candidate 64Cu-labeled antibodies targeting seven antigens (EGFR, HER2, HER3, TfR, EpCAM, LAT1, and CD98), which are reportedly overexpressed in patients with pancreatic cancer. We investigated the feasibility of 64Cu-TuBA to select the highest-binding antibody for individual cancer cell lines and predict the treatment response in vivo for 64Cu-ipRIT. 64Cu-TuBA was performed using six human pancreatic cancer cell lines. For three cell lines, an in vivo treatment study was performed with 64Cu-ipRIT using high-, middle-, or low-binding antibodies in each peritoneal dissemination mouse model. The high-binding antibodies significantly prolonged survival in each mouse model, while low-and middle-binding antibodies were ineffective. There was a correlation between in vitro cell binding and in vivo therapeutic efficacy. Our findings suggest that 64Cu-TuBA can be used for patient selection to enable personalized 64Cu-ipRIT. Tumor cells isolated from surgically resected tumor tissues would be suitable for analysis with the 64Cu-TuBA system in future clinical studies.

Usefulness of PET-guided surgery with 64Cu-labeled cetuximab for resection of intrapancreatic residual tumors in a xenograft mouse model of resectable pancreatic cancer

BACKGROUND

In pancreatic cancer surgery, accurate identification and resection of intrapancreatic residual tumors are quite difficult. We have developed a novel open-typed PET system (called 'OpenPET'), which enables high-resolution PET-guided surgery in real time, and demonstrated that OpenPET-guided surgery with intraperitoneally administered 64Cu-labeled anti-epidermal growth factor receptor antibody cetuximab is useful to detect and resect primary pancreatic cancer. Here, we investigated applicability of OpenPET-guided surgery for unexpected residual intrapancreatic tumors and examined its survival benefit over conventional surgery.

METHODS

A mouse model with large (>1 cm) resectable pancreatic cancer of xPA-1-DC cells expressing red fluorescent protein was used. OpenPET-guided surgery was conducted 24 h after intraperitoneal administration of 64Cu-labeled cetuximab (7.4 MBq/mouse). For comparison, similar surgical procedures were conducted, and conventional tumor resection was attempted using only the naked eye (control). Survival rate after OpenPET-guided surgery was compared to that after control operations.

RESULTS

Intraoperative OpenPET guidance enabled detection and resection of small residual tumors. Ten residual tumor specimens (3-10 mm in diameter) were intraoperatively isolated with OpenPET guidance (n = 7 mice). All isolated specimens showed tumor RFP signals. No resection of tumor tissue was performed in control group because the tumor could not be clearly detected with the naked eye alone. Mice after OpenPET-guided surgery showed significantly longer survival rates than those in control group.

CONCLUSIONS

OpenPET-guided surgery with 64Cu-labeled-cetuximab enabled intraoperative identification and resection of intrapancreatic small residual tumors. This technology could be useful to prevent tumor residuals during surgery and improve pancreatic cancer survival.

Xenografts Derived From Patients' Ascites Recapitulate the Gemcitabine Resistance Observed in Pancreatic Cancer Patients

OBJECTIVES

Most patient-derived pancreatic ductal adenocarcinoma (PDAC) xenografts have been established from surgical specimens of patients who have not received chemotherapy. However, xenografts have rarely been established from chemotherapy-resistant, advanced PDACs, because such cases are usually inoperable. The purpose of this study is to establish patient-derived xenografts using PDAC cells refractory to chemotherapy.

METHODS

Clinical PDAC cells obtained from ascites of patients who had received continuous chemotherapy were implanted into the flanks of immunocompromised mice. Growth and histological features of the xenografts with and without gemcitabine treatment were then analyzed.

RESULTS

Ascites-derived PDAC cells were successfully expanded through serial xenograft passage without changes in histological appearance. While treatment with gemcitabine substantially inhibited the growth of all PDAC xenografts tested, the tumor volume gradually increased, and the tumors showed marked regrowth even under continued gemcitabine treatment. These findings are consistent with the actual clinical course of the corresponding patients for each xenograft.

CONCLUSIONS

Ascites-derived xenograft models represent a valuable experimental system for testing the efficacy of currently available therapeutic compounds on chemotherapy-resistant PDAC cells and for elucidation of the mechanisms underlying chemotherapy resistance.

64Cu-Intraperitoneal Radioimmunotherapy: A Novel Approach for Adjuvant Treatment in a Clinically Relevant Preclinical Model of Pancreatic Cancer

Pancreatic cancer (PC) has a very poor prognosis. Surgery is the primary treatment for patients with resectable PC; however, local recurrence, hepatic metastasis, and peritoneal dissemination often occur even after extensive surgery. Adjuvant chemotherapy, typically with gemcitabine, has been used clinically but with only a modest survival benefit. To achieve a better outcome, we investigated the efficacy of 64Cu-intraperitoneal radioimmunotherapy (ipRIT) with 64Cu-labeled antiepidermal growth factor receptor antibody cetuximab as an adjuvant treatment after PC surgery using an orthotopic xenografted mouse model. Methods: The efficacy of adjuvant 64Cu-ipRIT was investigated in a human PC mouse model harboring orthotopic xenografts of xPA-1-DC cells. To reproduce the clinical situation, PC xenografts were surgically resected when pancreatic tumors were readily visible but not metastatic tumors. Increasing doses of 64Cu-cetuximab were intraperitoneally injected, and the mice were monitored for toxicity to determine the safe therapeutic dose. For adjuvant 64Cu-ipRIT, the day after tumor resection, the mice were intraperitoneally administered 22.2 MBq of 64Cu-PCTA-cetuximab and the survival was compared with that in surgery-only controls. For comparison, adjuvant chemotherapy with gemcitabine was also examined using the same model. Results: The mouse model not only developed primary tumors in the pancreas but also subsequently reproduced local recurrence, hepatic metastasis, and peritoneal dissemination after surgery, which is similar to the manifestations that occur with human PC. Adjuvant 64Cu-ipRIT with 64Cu-labeled cetuximab after surgery effectively suppressed local recurrence, hepatic metastasis, and peritoneal dissemination in this model. Significant improvement of the survival with minimal toxicity was achieved by adjuvant 64Cu-ipRIT compared with that in control mice that underwent surgery only. Adjuvant chemotherapy with gemcitabine nominally prolonged the survival, but the effect was not statistically significant. Conclusion:64Cu-ipRIT with cetuximab can be an effective adjuvant therapy after PC surgery.

Decreased serum carbohydrate antigen 19-9 levels after neoadjuvant therapy predict a better prognosis for patients with pancreatic adenocarcinoma: a multicenter case-control study of 240 patients

Background

Carbohydrate antigen (CA) 19–9 levels after resection are considered to predict prognosis; however, the significance of decreased CA19–9 levels after neoadjuvant therapy has not been clarified. This study aimed to define the prognostic significance of decreased CA19–9 levels after neoadjuvant therapy in patients with pancreatic adenocarcinoma.

Methods

Between 2001 and 2012, 240 consecutive patients received neoadjuvant therapy and subsequent resection at seven high-volume institutions in Japan. These patients were divided into three groups: Normal group (no elevation [≤37 U/ml] before and after neoadjuvant therapy), Responder group (elevated levels [> 37 U/ml] before neoadjuvant therapy but decreased levels [≤37 U/ml] afterwards), and Non-responder group (elevated levels [> 37 U/ml] after neoadjuvant therapy). Analyses of overall survival and recurrence patterns were performed. Uni- and multivariate analyses were performed to clarify the clinicopathological factors influencing overall survival. The initial metastasis sites were also evaluated in these groups.

Results

The Responder group received a better prognosis than the Non-responder group (3-year overall survival: 50.6 and 41.6%, respectively, P = 0.026), but the prognosis was comparable to the Normal group (3-year overall survival: 54.2%, P = 0.934). According to the analysis of the receiver operating characteristic curve, the CA19–9 cut-off level defined as no elevation after neoadjuvant therapy was ≤103 U/ml. The multivariate analysis revealed that a CA19–9 level ≤ 103 U/ml, (P = 0.010, hazard ratio: 1.711; 95% confidence interval: 1.133–2.639), tumor size ≤27 mm (P = 0.040, 1.517; (1.018–2.278)), a lack of lymph node metastasis (P = 0.002, 1.905; (1.276–2.875)), and R0 status (P = 0.045, 1.659; 1.012–2.627) were significant predictors of overall survival. Moreover, the Responder group showed a lower risk of hepatic recurrence (18%) compared to the Non-responder group (31%), though no significant difference in loco-regional, peritoneal or other distant recurrence were observed between groups (P = 0.058, P = 0.700 and P = 0.350, respectively).

Conclusions

Decreased CA19–9 levels after neoadjuvant therapy predicts a better prognosis, with low incidence of hepatic recurrence after surgery.

Electronic supplementary material

The online version of this article (10.1186/s12885-019-5460-4) contains supplementary material, which is available to authorized users.

Defining Early Recurrence of Hilar Cholangiocarcinoma After Curative-intent Surgery: A Multi-institutional Study from the US Extrahepatic Biliary Malignancy Consortium

BACKGROUND

Time to tumor recurrence may be associated with outcomes following resection of hepatobiliary cancers. The objective of the current study was to investigate risk factors and prognosis among patients with early versus late recurrence of hilar cholangiocarcinoma (HCCA) after curative-intent resection.

METHODS

A total of 225 patients who underwent curative-intent resection for HCCA were identified from 10 academic centers in the USA. Data on clinicopathologic characteristics, pre-, intra-, and postoperative details and overall survival (OS) were analyzed. The slope of the curves identified by linear regression was used to categorize recurrences as early versus late.

RESULTS

With a median follow-up of 18.0 months, 99 (44.0%) patients experienced a tumor recurrence. According to the slope of the curves identified by linear regression, the functions of the two straight lines were y = -0.465x + 16.99 and y = -0.12x + 7.16. The intercept value of the two lines was 28.5 months, and therefore, 30 months (2.5 years) was defined as the cutoff to differentiate early from late recurrence. Among 99 patients who experienced recurrence, the majority (n = 80, 80.8%) occurred within the first 2.5 years (early recurrence), while 19.2% of recurrences occurred beyond 2.5 years (late recurrence). Early recurrence was more likely present as distant disease (75.1% vs. 31.6%, p = 0.001) and was associated with a worse OS (Median OS, early 21.5 vs. late 50.4 months, p < 0.001). On multivariable analysis, poor tumor differentiation (HR 10.3, p = 0.021), microvascular invasion (HR 3.3, p = 0.037), perineural invasion (HR 3.9, p = 0.029), lymph node metastases (HR 5.0, p = 0.004), and microscopic positive margin (HR 3.5, p = 0.046) were independent risk factors associated with early recurrence.

CONCLUSIONS

Early recurrence of HCCA after curative resection was common (~35.6%). Early recurrence was strongly associated with aggressive tumor characteristics, increased risk of distant metastatic recurrence and a worse long-term survival.

Expression of phosphorylated estrogen receptor beta is an independent negative prognostic factor for pancreatic ductal adenocarcinoma

PURPOSE

The role of estrogen receptor beta (ER-β) expression in pancreatic ductal adenocarcinoma (PDAC) is largely unknown. Ligand-independent phosphorylation and activation of ER-β may play a relevant role in the IL-6/STAT3 signaling pathway and, as a result, in tumor progression. Here, we examined the effect of ER-β, phosphorylated ER-β (pER-β), STAT3, phosphorylated STAT3 (pSTAT3) and IL-6 expression on the overall and recurrence-free survival in a cohort of patients with resected PDAC.

METHODS

We identified 175 patients who underwent pancreatic resection for PDAC. Tissue microarrays were constructed from the archival tumor specimens. These were stained with specific antibodies for the above molecules. The expression of the markers was then correlated with clinicopathological parameters and survival analysis was performed.

RESULTS

High nuclear expression of ER-β was found in 61.7% and pER-β in 80.6% of the tumors. STAT3 was expressed in 54.3% of the tumor samples, pSTAT3 in 68% and IL-6 in 76.6%. The median overall survival for patients with low pER-β expression was 29 months, whereas for patients with high pER-β expression was 15.1 months (p = 0.016). Multivariate analysis revealed that pER-β expression was an independent factor correlating with shorter overall survival (hazard ratio 1.9; p = 0.013) and disease-free survival (hazard ratio 1.9; p = 0.029).

CONCLUSIONS

Expression of pER-β constitutes an independent prognostic marker for PDAC and is correlated with poor prognosis. These data may help in identifying novel drug targets in PDAC and patients who could benefit from additional therapeutic regimens, including selective estrogen receptor modulators.

Predictive role of human equilibrative nucleoside transporter 1 in patients with pancreatic cancer treated by curative resection and gemcitabine-only adjuvant chemotherapy

The predictive roles of human equilibrative nucleoside transporter 1 (hENT-1) in patients who undergo curative resection and adjuvant chemotherapy with gemcitabine alone have not been established. The present study retrospectively analyzed the clinical data from 101 consecutive patients who underwent curative resection and who received gemcitabine adjuvant chemotherapy for the treatment of pancreatic cancer at Kanagawa Cancer Center (Yokohama, Japan) between 2005 and 2014. The associations between the hENT-1 status and the survival and clinicopathological features of the patients were investigated. Of the 101 patients, 60 patients (59.4%) had high levels of hENT-1 expression. A significant association was observed between hENT-1 status and sex; however, for all the other clinicopathological parameters, including tumor and node stages, no differences were observed between the high and low hENT-1 expression groups. The median follow-up period of the present study was 67.3 months. Between the high and low hENT-1 expression groups, there was a statistically significant difference in the 5-year overall survival (OS) rates following surgery (20.6 and 8.9%, respectively; P=0.019). In addition, a significant difference was observed in the recurrence-free survival (RFS) rates at 5 years following surgery (P=0.049). hENT-1 status was one of the important predictive factors for OS and RFS in patients with pancreatic cancer who underwent curative resection followed by adjuvant chemotherapy with gemcitabine. Adjuvant chemotherapy with gemcitabine alone may be insufficient, particularly in patients with certain relevant risk factors.

Clinical implications of ribonucleotide reductase subunit M1 in patients with pancreatic cancer who undergo curative resection followed by adjuvant chemotherapy with gemcitabine

To the best of our knowledge, the clinical implications of using ribonucleoside reductase subunit M1 (RRM1) in patients who undergo curative resection and adjuvant chemotherapy have not been established. In the present study, the clinical data from 101 consecutive patients who underwent macroscopically curative resection, and who received adjuvant gemcitabine chemotherapy for pancreatic cancer at the Kanagawa Cancer Centre (Yokohama, Kanagawa, Japan) between April 2005 and December 2014 were retrospectively analyzed. The association between the RRM1 status and survival and clinicopathological features were assessed. Of the 101 patients, 41 patients expressed high levels of RRM1 expression (40.6%). Although a significant difference was observed in lymphatic invasion, there was no difference between the two groups with regard to any other clinicopathological parameters. The median follow-up period was 67.3 months. There was a significant difference between the recurrence-free survival (RFS) rates at 5 years after surgery, which were 12.9 and 0% in the high RRM1 and low RRM1 groups, respectively (P=0.042). Furthermore, there was a significant difference in the 5-year overall survival (OS) rates following surgery, which were 5.1 and 21.5% in the high RRM1 and low RRM1 groups, respectively (P=0.015). The results of the present study indicated that out of the factors assessed, RRM1 was the most important prognostic factor for OS and RFS in patients with pancreatic cancer who underwent curative resection followed by adjuvant chemotherapy with gemcitabine. Adjuvant chemotherapy with gemcitabine alone may be insufficient for the treatment of pancreatic cancer, particularly in patients with relevant risk factors.

Preoperative radiographic vascular involvement score predicts the prognosis of resected pancreatic head adenocarcinoma

BACKGROUND

Operative indications for pancreatic head adenocarcinoma (PHC) with vascular invasion remain unclear. We aimed to develop a new prognostic model focusing on preoperative portal/superior mesenteric vein (PV/SMV) and superior mesenteric artery (SMA) invasiveness.

METHODS

From 2005 to 2012, 103 patients underwent pancreatoduodenectomy for PHC. The CT findings for both PV/SMV and SMA invasion were evaluated separately [PV/SMV, none (score 0), unilateral narrowing (score 1), bilateral narrowing/stenosis (score 2); SMA, none or <90° (score 0), ≥90° (score 3)]. The total score defined the preoperative vascular involvement score (VI score); VI scores 0 (n = 39), 1 (n = 32), 2 (n = 17) and ≥3 (n = 15) were compared.

RESULTS

PV/SMV resection was performed in 1 (3%), 29 (91%), 16 (94%) and 13 (87%) cases of VI scores 0, 1, 2 and ≥3, respectively (P < 0.001). No patients with VI scores ≥3 had margin-negative resection; pathologically curative resection was achieved in 37 of 39 (95%), 27 of 32 (84%) and 13 of 17 (76%) patients with VI scores of 0, 1 and 2, respectively (P < 0.001). The survival rate and median survival time (MST) were reduced with an increasing VI score (MST, 40.9, 16.5, 8.9 and 6.3 months, respectively). The comparison of each survival curve revealed significant differences (P < 0.005), except when comparing VI scores 1 and 2 (P = 0.134).

CONCLUSIONS

Higher VI score predicts shorter survival. Proposed scoring system may be useful for determining the choice between undergoing neoadjuvant treatment, or upfront resection with adjuvant treatment.

The c.657del5 variant in the NBN gene predisposes to pancreatic cancer

Pancreatic ductal adenocarcinoma (PDAC) is the sixth most frequent cancer type in the Czech Republic with a poor prognosis that could be improved by an early detection and subsequent surgical treatment combined with chemotherapy. Genetic factors play an important role in PDAC risk. We previously identified one PDAC patient harboring the Slavic founder deleterious mutation c.657del5 in the NBN gene, using a panel next-generation sequencing (NGS). A subsequent analysis of 241 unselected PDAC patients revealed other mutation carriers. The overall frequency of c.657del5 in unselected PDAC patients (5/241; 2.07%) significantly differed from that in non-cancer controls (2/915; 0.2%; P=0.006). The result indicates that the NBN c.657del5 variant represents a novel PDAC-susceptibility allele increasing PDAC risk (OR=9.7; 95% CI: 1.9 to 50.2). The increased risk of PDAC in follow-up recommendations for NBN mutation carriers should be considered if other studies also confirm an increased frequency of c.657del5 carriers in PDAC patients from other populations.

No-touch isolation techniques for pancreatic cancer

The rate of recurrence, including liver metastasis is high in pancreatic cancer, even when complete surgical resection is performed as a curative treatment. In patients with pancreatic cancer, the handling and grasping of the pancreas during surgery may increase the risk of liver metastasis, as squeezing may spread cancer cells via the portal vein. A no-touch isolation technique might prevent the spread of cancer cells via the hematogenous metastatic route in patients with pancreatic cancer. However, while no-touch isolation techniques are simple, feasible and, in theory, ideal procedures for the surgical treatment of pancreatic cancer, there have been no randomized controlled prospective studies to validate their advantages and their efficacy remains controversial. It is, therefore, worth investigating the use of no-touch isolation techniques in pancreatic cancer.

A prospective, randomized trial of pancreatectomy combined with isolated hepatic perfusion via a dual route or conventional postoperative adjuvant therapy in patients with advanced pancreatic head carcinoma

Prognosis of locally advanced pancreatic head carcinoma after Whipple remains poor. This study is to investigate the efficacy and safety of regional lymphadenectomy and chemotherapy of isolated hypoxic perfusion (IHP) via dual-route, and to analyze the effect for survival period. Consecutive patients subjected to our department from January 1, 2006 to December 31 2011 for locally advanced pancreatic head carcinoma were prospectively divided into two groups according to therapeutic modality, and clinical and follow-up data was recorded. In study group, operation duration and postoperative stay time were shorter, blood loss and blood transfusion were less, and incidence of complications was lower. The mean and median survival time was 17.4 ± 0.76 months and 18.0 months in study group, longer than control group of 14.1 ± 0.85 months and 17.6 months. Regional lymphadenectomy can be performed with low mortality and morbidity, and combined postoperative IHP via dual-route can improve survival time.

Extended lymphadenectomy in pancreatic cancer is crucial

Lymph node metastasis is considered one of the most significant factors associated with postoperative prognosis in patients with pancreatic cancer. Some prospective studies found no significant differences in survival between patients who underwent pancreatic cancer surgery with extended lymphadenectomy and those who underwent surgery with standard lymphadenectomy. However, recent reports, such as those describing the significance of the metastatic to examined lymph node ratio, suggest the need for some degree of lymphadenectomy. This review describes the findings of published studies and discusses the usefulness of LN dissection in patients with pancreatic cancer.

(68)Ga-radiopharmaceuticals for PET imaging of infection and inflammation

Infection imaging has been challenging over the past four decades, which provided an excellent playing field for researchers working in this area, and till date the quest continues to find an ideal imaging agent. Labelled leukocytes were first developed in the 1970s for imaging infection lesions such as osteomyelitis, cellulitis, diabetic foot, Crohn's disease, inflammatory bowel disease, fever of unknown origin, etc. Subsequently labelled antibiotics such as (99m)Tc-labelled ciprofloxacin have emerged for directly identifying live bacterial infections. From the early 1970s through the mid-1980s,( 67)Ga-Citrate was the prime radionuclide for imaging of inflammation and infection of musculoskeletal origin. Although (68)Ga-PET was described in 1960s for tumour imaging, recent reports described (68)Ga-Citrate and (68)Ga-transferrin as possible agents for PET-imaging of infection due to successful application of (67)Ga-Citrate SPECT in the past, despite its limitations. It is important to establish a faster imaging method for (68)Ga, as its half-life is 68 min compared to 78.3 hrs for (67)Ga. Preparation of (68)Ga-Citrate and (68)Ga-transferrin is described, with very high yield and high radiochemical purity (RCP), which is ideally suited for routine clinical studies. Biodistribution of (68)Ga-Citrate-PET images were characterised with high blood pool, high liver and bone (growth plate) uptake with low soft-tissue activity. (68)Ga-Citrate or (68)Ga-transferrin was able to detect infected lesions in rats within 5-10 min post injection but a focal intense uptake at the lesion (SUV(max)) was visualized only at 30 min, which increased for up to 6 hrs post injection with concomitant decrease in the cardiac blood pool activity. The liver and bowel activity decreased after 90 min then stabilised. In the patient studies, infection lesions were detected within 30 min post injection of (68)Ga-Citrate. Cardiac blood pool and liver activities decreased during the period of study. Interestingly, there was persistent high vascular activity in the thigh region. One of the major limitations of (67)Ga-Citrate SPECT is the delayed post injection waiting time of 48 hrs, in contrast to 60 min post injection waiting with (68)Ga-Citrate. The distinct difference in imaging time is intriguing, although there is no chemical difference between (67)Ga-Citrate and (68)Ga-Citrate, except for the radiolabel. No literature is available on early imaging times using (67)Ga-SPECT. When compared (68)Ga/(67)Ga-Citrate images at 60 min post injection in normal rats, (68)Ga-PET showed better images with low background activity than (67)Ga-SPECT agent. This may be due to short half-life of (68)Ga (68 min), as it would have decayed one half-life at 60 min post-imaging time, compared to the SPECT agent ((67)Ga), which would require 76 hrs to undergo one half-life. Therefore, the visual difference in background can be attributed to the difference in the half-lives of these two agents. Similarly, uptake of (68)Ga by liver, cardiac blood pool activity is much lower than (67)Ga at 60 min post injection period, may be attributed to the faster decay of (68)Ga than (67)Ga. High background activity of (68)Ga-Citrate in the thorax and upper abdomen at 60 min post-injection may interfere with detecting lesions in these regions; therefore, (68)Ga-PET is more suitable for imaging lesions in the lower abdomen and the extremities. The short half-life of (68)Ga (68 min) may be advantageous from low dosimetry to the patients, but disadvantageous for longer periods of study. Since (68)Ga-Citrate was capable of detecting infection within 60 min, the need for imaging for longer periods may not be warranted. The functional imaging was not limited to diagnosing infection but it could be extended to surgical planning and antibiotic therapy monitoring of osteomyelitis and in distinguishing prosthetic infection from loosening of prosthesis. (18)F-FDG is sensitive but has the limitation of giving false positive results in patients with bone prosthesis, even if there is no infection or mobilisation. But the available literature clearly indicated (68)Ga-Citrate was positive only in cases of infection. In summary, preliminary reports suggest (68)Ga-Citrate PET/CT is useful in the diagnosis of suspected bone infections with reliable sensitivity, specificity, positive predictive value, negative predictive value and overall accuracy. Preliminary reports with (68)Ga-Transferrin showed it is capable of detecting both Gram-positive Staphylococcus aureus (Staph A) and Gram-negative Proteus mirobilis. This is an incidental finding but gives an insight into the potential of this agent to detect more than one bacterial infection.

Clinicopathologic study of intrapancreatic cancer spread in carcinoma of the body and tail of the pancreas

OBJECTIVE

The aims of this study were to clarify the type of intrapancreatic spread of cancer of the pancreatic body and tail and to assess whether a 2-cm transection margin is adequate to ensure negative margins.

METHODS

We selected 66 patients who underwent distal pancreatectomy for cancer of the pancreatic body and tail. We investigated intrapancreatic cancer spread in these patients histopathologically and analyzed the relationship between 2-cm-margin positivity and other clinicopathological characteristics.

RESULTS

Two-centimeter-margin positivity was observed in 17 cases. In these, tumors had a tendency to spread toward the pancreatic head along the main pancreatic duct. As a result of statistical analysis, we considered venous invasion (odds ratio [OR], 15.48; 95% confidence interval [CI], 1.61-148.94; P = 0.0177), 2-cm-margin fibrosis (OR, 173.88; 95% CI, 8.96-3375.03; P = 0.0007), and 2-cm-margin hardness (OR, 5.97; 95% CI, 1.07-33.46; P = 0.0420) as being independently related to 2-cm-margin positivity.

CONCLUSIONS

The results suggest that 2 cm is not a safe length to ensure a negative margin. In the future, preoperative and intraoperative evaluation of the degree of fibrosis of pancreatic parenchyma could lead to cancer-free pancreatic cut-end margins.

Significance of lymph node micrometastasis in pancreatic cancer patients

BACKGROUND /AIMS: The present study deals with the significance of lymph node micrometastasis in the survival rate for pancreatic cancer patients.

METHODS

Between January 2006 and December 2010 at the First Department of Surgery in Košice, a prospective trial was done in which we investigated the survival rate after radical pancreatic resection. All negative lymph nodes removed during standard radical lymphadenectomy were subjected to immunohistochemical staining to detect occult micrometastasis. A comparison of the median survival rate in groups of patients with immunohistochemistry-positive and -negative lymph nodes was performed.

RESULTS

Radical pancreatic resection with standard radical lymphadenectomy was performed on 64 pancreatic cancer patients. The median survival time was 15 months. Out of the 319 histopathologically negative lymph nodes (34 patients), 134 lymph nodes were classified as immunohistochemistry positive (21 patients). The median survival rate in the group of patients with immunohistochemistry-negative lymph nodes was 23 months, but in the group of patients with immunohistochemistry-positive lymph nodes it was 14 months. There was a statistically significant difference between these 2 groups of patients (p ≤ 0.01).

CONCLUSION

The immunohistochemical examination of histopathologically negative lymph nodes can lead to positive lymph node detection. The presence of lymph node micrometastasis could predict the survival rate.

Pattern of lymph node metastasis spread in pancreatic cancer

OBJECTIVES

We aimed to clarify the detailed pattern of lymph node (LN) metastasis spread in patients with pancreatic cancer.

METHODS

This retrospective study enrolled 429 patients who underwent pancreatectomy with extended lymphadenectomy for pancreatic cancer. The prognostic implications of LN metastasis were evaluated, and the position, frequency, and association with other clinicopathologic factors were investigated.

RESULTS

Lymph node metastasis was confirmed pathologically in 289 patients (67.4%). The prognosis of patients with LN metastasis was significantly poorer than that of patients without LN metastasis (P < 0.001). Distant LN metastasis occurred frequently, regardless of the tumor site. Patients classified with T1 or T2 only had regional LN metastasis, whereas there was a high rate of distant LN metastasis, including the para-aortic LNs, in patients with T3 or higher-stage tumors. Para-aortic LN metastasis was significantly associated with arterial and perineural invasion (P = 0.006 and P < 0.001, respectively). Lymph node metastasis in the hepatic portal region was a strong predictor of para-aortic LN metastasis in pancreatic head cancer.

CONCLUSIONS

Pancreatic cancer frequently metastasized to distant LNs via a complex pathway and developed into systemic disease. Aggressive multimodality therapy, including neoadjuvant therapy, is essential to improve the long-term survival of patients at substantial risk of distant LN metastasis.

Nutritional predictors of postoperative outcome in pancreatic cancer

BACKGROUND

Nutritional status plays an important role in the incidence of postoperative complications and the prognosis of various tumours. The prognostic value of preoperative nutritional factors in patients with pancreatic cancer is not known.

METHODS

This retrospective study included 268 patients who underwent resection for adenocarcinoma of the pancreas. The predictive value of preoperative nutritional status for postoperative outcome (survival, complications) was assessed. Nutritional factors included the three constitutional indices, serum albumin and Onodera's prognostic nutrition index (PNI), calculated as 10 × serum albumin (g/dl) + 0·005× total lymphocyte count (per mm(3)).

RESULTS

In multivariable analysis preoperative low PNI (but not low albumin) was an independent prognostic factor for poor survival: hazard ratio (HR) 1·73 (95 per cent confidence interval (c.i.) 1·21 to 2·47). The accuracy of a PNI value of less than 45 as cut-off for clinically significant preoperative malnutrition in predicting 1- or 2-year survival after surgery was, however, limited (66·4 and 56·3 per cent respectively). Low preoperative albumin concentration and PNI were significantly associated with postoperative complications: odds ratio 1·98 (95 per cent c.i. 1·18 to 3·32) and 2·14 (1·23 to 3·73) respectively. Low PNI and low body mass index were independently associated with pancreatic fistula: HR 2·52 (1·37 to 4·63) and 0·40 (0·17 to 0·93) respectively.

CONCLUSION

The PNI is associated with overall survival and postoperative complications, in particular pancreatic fistula, in patients with pancreatic cancer. The moderate accuracy of PNI as a predictor of survival limits its clinical use.

Postoperative complications and survival rates for pancreatic cancer patients

BACKGROUND/AIMS

Surgical resection offers the only potential cure for pancreatic tumor. The goal of the present study is to determine complications associated with pancreatic resection and to describe their influence on the survival rate for pancreatic cancer patients.

MATERIALS AND METHODS

Between 1996 and 2009, the findings of 125 pancreatic cancer patients were analyzed in a prospective trial at the First Department of Surgery, University Hospital in Košice, Slovakia.

RESULTS

The overall mortality rate and morbidity rate were 3.2% (4 patients) and 27% (34 patients), respectively. In patients with postoperative complications, the median survival time was 12 months (range, 8-14 months), in patients without complications - 18 months (range, 15-20 months).

CONCLUSION

The presence of postoperative complications after pancreatic resections has negative influence on the survival rate for pancreatic cancer patients. Patients with a small pancreatic duct size (<3 mm) or a soft pancreatic remnant were at high risk of pancreatic leakage and postoperative complications.

Divalent cations modulate alpha2beta1 integrin-mediated malignancy in a novel 3-dimensional in vitro model of pancreatic cancer

OBJECTIVES

We previously showed that divalent cations regulate alpha2beta1 integrin-mediated pancreatic cancer cell interactions with type I collagen in 2 dimensions (2D), including cell adhesion, migration, and proliferation. Presently, we examined divalent cation-dependent alpha2beta1 integrin-mediated pancreatic cancer cell adhesion and proliferation on type I collagen in a novel 3D in vitro model.

METHODS

Cell attachment, proliferation, and antibody inhibition assays on type I collagen in both 2D and 3D, and microscopy and immunoblotting were used for these studies.

RESULTS

As in 2D, cell attachment on type I collagen in 3D is Mg-dependent and inhibited by Ca. Proliferation in 3D is also Mg-dependent, but maximal when Mg is present at concentrations that promote maximal cell adhesion and Ca is present at concentrations less than Mg. Immunoblotting studies demonstrate that the divalent cation-dependent changes in cell-cell adhesion observed on type I collagen in both 2D and 3D are associated with the changes in E-cadherin and beta-catenin expression. Antibody inhibition assays indicate further that the alpha2beta1 integrin specifically mediates proliferation on type I collagen in 3D under altered divalent cation conditions.

CONCLUSIONS

Divalent cation shifts could activate alpha2beta1 integrin-mediated malignancy in the type I collagen-rich 3D tumor microenvironment of pancreatic cancer.

PET imaging of inflammation and adenocarcinoma xenografts using vascular adhesion protein 1 targeting peptide 68Ga-DOTAVAP-P1: comparison with 18F-FDG

PURPOSE

The aim of this study was to evaluate inflammation and tumour imaging with a vascular adhesion protein 1 (VAP-1) targeting peptide (68)Ga-DOTAVAP-P1 in comparison with (18)F-FDG.

METHODS

Rats with both subcutaneous human pancreatic adenocarcinoma xenografts and turpentine oil-induced acute sterile inflammation were evaluated by dynamic positron emission tomography (PET) and by digital autoradiography of tissue cryosections. Subsequently, the autoradiographs were combined with histological and immunohistological analysis of the sections.

RESULTS

(68)Ga-DOTAVAP-P1 delineated acute, sterile inflammation comparable with (18)F-FDG. However, the tumour uptake of (68)Ga-DOTAVAP-P1 was low in contrast to prominent (18)F-FDG uptake. The standardised uptake values of inflammation and tumours by PET were 1.1 +/- 0.4 (mean +/- SEM) and 0.4 +/- 0.1 for (68)Ga-DOTAVAP-P1 and 2.0 +/- 0.5 and 1.6 +/- 0.8 for (18)F-FDG, respectively. In addition, PET studies showed inflammation to muscle and tumour to muscle ratios of 5.1 +/- 3.1 and 1.7 +/- 0.3 for (68)Ga-DOTAVAP-P1 and 6.2 +/- 0.7 and 4.6 +/- 2.2 for (18)F-FDG, respectively. Immunohistochemistry revealed increased expression of luminal VAP-1 on the endothelium at the site of inflammation and low expression in the tumour

CONCLUSION

The (68)Ga-DOTAVAP-P1 PET was able to visualise inflammation better than tumour, which was in accordance with the luminal expression of VAP-1 on vasculature in these experimental models.

RNAi targeting EZH2 inhibits tumor growth and liver metastasis of pancreatic cancer in vivo

The function of EZH2 in tumorigenesis and liver metastasis of pancreatic cancer has never been elucidated in vivo. EZH2 was overexpressed in pancreatic carcinomas and its overexpression was associated with tumor differentiation and pT status. Suppression of EZH2 caused a significant growth inhibition of pancreatic cancer cells in vitro and markedly diminished their tumorigenicity in vivo. Knock-down of EZH2 inhibited liver metastasis of pancreatic cancer in vivo. EZH2 has a crucial role in tumor growth and liver metastasis of pancreatic cancer.

68Ga-chloride PET reveals human pancreatic adenocarcinoma xenografts in rats--comparison with FDG

PURPOSE

The aim of the study was to compare (68)Ga-chloride with 2-[(18)F]fluoro-2-deoxy-D: -glucose (FDG) for the imaging of pancreatic xenografts.

PROCEDURES

Rats with subcutaneous human pancreatic adenocarcinoma xenografts were evaluated in vivo by dynamic positron emission tomography (PET) and ex vivo by measuring radioactivity of excised tissues and by digital autoradiography of tumor cryosections.

RESULTS

Both tracers were capable of delineating all subcutaneous tumors from surrounding tissues by PET. The standardized uptake values of tumors by PET were 0.9 +/- 0.3 (mean +/- SD) for (68)Ga-chloride (n = 13) and 1.8 +/- 1.2 for FDG (n = 11). Ex vivo studies showed tumor-to-muscle ratio of 4.0 +/- 0.3 for (68)Ga-chloride (n = 4) and 7.9 +/- 3.2 for FDG (n = 4).

CONCLUSIONS

(68)Ga-chloride delineated subcutaneously implanted pancreatic adenocarcinoma xenografts by PET, but the uptake was lower than FDG. Further studies to clarify the value of (68)Ga-chloride for PET imaging of tumors are warranted.

Invasion of the splenic artery is a crucial prognostic factor in carcinoma of the body and tail of the pancreas

OBJECTIVES

A retrospective study was performed to determine the prognostic implications of invasion to the splenic vessels in pancreatic body and tail cancer.

SUMMARY BACKGROUND DATA

Involvement of the splenic artery (SA) and vein (SV) is frequently observed in carcinoma of the body and tail of the pancreas, but its correlation with various other clinicopathologic factors and prognosis has not been explored in detail.

METHODS

Fifty-one patients who had undergone distal pancreatectomy for invasive adenocarcinoma of the body and tail of the pancreas were discreetly selected from the prospective data base for analyses. Cases that required extended surgery due to invasion of the major vessels such as the portal vein, common hepatic artery, celiac artery, and superior mesenteric artery were excluded. Correlation between invasion of the splenic vessels and prognosis and other clinicopathologic factors were analyzed.

RESULTS

Seventeen patients with invasion of the SA had a significantly inferior prognosis compared with those without the invasion (P = 0.0067), whereas invasion of the SV, observed in 24 patients, did not affect prognosis. Additionally, invasion of the SA significantly correlated with tumor size > or = 2 cm, anterior serosal infiltration, perineural invasion and SV invasion (P = 0.0440, P = 0.0406, P = 0.0460, and P = 0.0173, respectively). In univariate analysis, SA invasion, lymph node metastasis, and anterior serosal infiltration were identified as significant poor prognostic factors. In multivariable analysis, only SA invasion was an independent prognostic factor (odds ratio, 2.611, P = 0.0196).

CONCLUSIONS

Our results indicated that the invasion of the SA, but not that of the SV, is a crucial prognostic factor in pancreatic body and tail cancer.

Effective endovascular stenting of malignant portal vein obstruction in pancreatic cancer

We report herein the case of a patient successfully treated by transhepatic portal venous stent placement for malignant portal vein obstruction with associated gastric and small bowel varices and repeated gastrointestinal bleeding. CT angiography and portography showed severe portal vein obstruction from recurrent pancreatic cancer 15 months following pancreaticoduodenectomy with tumor encasement and dilated collateral veins throughout the gastric and proximal small bowel wall as the suspected cause of the GI bleeding. Successful transhepatic endovascular stent placement of the splenic vein at the portal vein confluence followed by balloon dilation was performed with immediate decompression of the gastric and small bowel varices and relief of GI hemorrhage in this patient until his death four months later. The treatment for patients with this dilemma can prove to be difficult, but as we have shown endovascular stenting of the portal system is an effective treatment option.

Prognostic factors for survival after extended pancreatectomy for pancreatic head cancer: influence of resection margin status on survival

OBJECTIVES

Although a positive resection margin has been reported to be a strong prognostic factor after resection for pancreatic cancer, several studies indicated that resection status did not independently affect survival. The aim of this study was to examine the influence of resection margin status on survival after extended radical resection for pancreatic head cancer.

METHODS

One hundred thirty-eight cases of pancreatoduodenectomy and 38 cases of pylorus-preserving pancreatoduodenectomy for invasive ductal carcinoma of the pancreas were retrospectively analyzed.

RESULTS

The resection margins were negative (R0) in 115 patients (65.3%), microscopically positive (R1) in 38 patients (21.6%), and grossly positive (R2) in 23 patients (13.1%). Patients with R1 resection survived significantly shorter (median survival time [MST], 9.4 months) than R0 resection patients (MST, 15.2 months) but survived longer than R2 resection patients (MST, 6.2 months). By multivariate analysis, R2 resection, together with lymph node metastasis, portal venous system, and extrapancreatic nerve plexus invasions, independently affected the overall survival, but R1 resection was not significantly influential.

CONCLUSIONS

R2 resection was an independent predictor of poor prognosis after pancreatoduodenectomy/pylorus-preserving pancreatoduodenectomy, whereas R1 resection did not independently affect the survival.

Experimental pancreatic cancer model using PGHAM-1 cells: characteristics and experimental therapeutic trials

We developed short-term pancreatic cancer models in hamsters using PGHAM-1 cells and examined the utility of the models for research on metastasis and for therapeutic trials. With 3 PGHAM-1 models, including 1) primary pancreatic cancer and simultaneous liver metastasis by intrapancreatic transplantation, 2) liver metastasis alone by intrasplenic transplantation, 3) peritoneal dissemination by intraperitoneal transplantation, within 21 days after inoculation, we studied the specific characteristics of metastases and the effects of several antiangiogenic substances on primary and metastatic pancreatic tumors. Several experiments showed that vascular endotherial growth factor and anatomical characteristics were important factors for metastasis. In therapeutic experiments, the incidence, size, diameter, microvessel density, and apoptotic index of the tumors were preferably influenced by the antiangiogenic substances. In addition, PGHAM-1-Luc, which is luciferase-positive PGHAM-1 cell line, was newly developed and is expected to be a useful new animal model. These models would be suitable for the study of pathogenesis of pancreatic cancer and its metastasis and for preclinical trials of chemotherapeutic agents, such as antiangiogenic substances.

Preoperative serum CA19-9 and dissected peripancreatic tissue margin as determiners of long-term survival in pancreatic cancer

BACKGROUND

Pancreatic cancer, a particularly deadly form of malignancy, has increased in the last decade worldwide. The purpose of this study is to identify markers for determining and identifying possible long-term survivors in cases of advanced pancreatic cancer.

PATIENTS AND METHODS

117 patients with pancreatic ductal carcinoma, including 89 with invasive tubular adenocarcinoma of the pancreas, Japan Pancreas Society (JPS) stage III-IVb patients, who underwent tumor resection between 1986 and 2006.

RESULTS

Univariate prognostic analyses of the 5-year disease-specific survival (DSS) revealed that JPS stage (P < 0.0001), preoperative serum carbohydrate antigen 19-9 (CA19-9) level (preCA19-9; P < 0.0001), dissected peripancreatic tissue margin (DPM; P < 0.0001), residual tumor (R factor; P = 0.0007), lymph node metastasis density over 10% (ND10; P = 0.006), volume of the stromal connective tissue (stroma factor; P = 0.008), growth pattern (P = 0.01), and histology (P = 0.03) were all significantly associated with poor outcome in advanced pancreatic cancer. Multivariate logistic analysis confirmed that preCA19-9 [P = 0.0006, relative risk (RR) = 2.16] and DPM (P = 0.04, RR = 1.62) were prognostic factors that remained, independent of JPS stage (P = 0.001). The higher preCA19-9 was, the worse the prognosis was. Astonishingly, among JPS stage III cases, 76.9% of the patients with preCA19-9 below 37 U/ml survived more than 5 years. This, combined with an analysis of DPM, allowed us to identify those with the potentiality for long-term survival.

CONCLUSION

Our results reveal for the first time that it is possible with JPS stage III-IVb invasive tubular adenocarcinomas of the pancreas to differentiate prognostic groups and potential survival rates, like with other cancers.

Surgical outcome of adenosquamous carcinoma of the pancreas

Adenosquamous carcinoma is rare, accounting for 3%-4% of all pancreatic carcinoma cases. These tumors are characterized by the presence of variable proportions of mucin-producing glandular elements and squamous components, the latter of which should account for at least 30% of the tumor tissue. Recently, several reports have described cases of adenosquamous carcinoma of the pancreas. However, as the number of patients who undergo resection at a single institute is limited, large studies describing the clinicopathological features, therapeutic management, and surgical outcome for adenosquamous carcinoma of the pancreas are lacking. We performed a literature review of English articles retrieved from Medline using the keywords 'pancreas' and 'adenosquamous carcinoma'. Additional articles were obtained from references within the papers identified by the Medline search. Our subsequent review of the literature revealed that optimal adjuvant chemotherapy and/or radiotherapy regimens for adenosquamous carcinoma of the pancreas have not been established, and that curative surgical resection offers the only chance for long-term survival. Unfortunately, the prognosis of the 39 patients who underwent pancreatic resection for adenosquamous carcinoma was very poor, with a 3-year overall survival rate of 14.0% and a median survival time of 6.8 mo. Since the postoperative prognosis of adenosquamous carcinoma of the pancreas is currently worse than that of pancreatic adenocarcinoma, new adjuvant chemotherapies and/or radiation techniques should be investigated as they may prove indispensible to the improvement of surgical outcomes.

MetMAb, the one-armed 5D5 anti-c-Met antibody, inhibits orthotopic pancreatic tumor growth and improves survival

The hepatocyte growth factor (HGF) and its receptor, c-Met, have been implicated in driving proliferation, invasion, and poor prognosis in pancreatic cancer. Here, we investigated the expression of HGF and c-Met in primary pancreatic cancers and described in vitro and in vivo models in which MetMAb, a monovalent antibody against c-Met, was evaluated. First, expression of HGF and MET mRNA was analyzed in 59 primary pancreatic cancers and 51 normal samples, showing that both factors are highly expressed in pancreatic cancer. We next examined HGF responsiveness in pancreatic cancer lines to select lines that proliferate in response to HGF. Based on these studies, two lines were selected for further in vivo model development: BxPC-3 (c-Met(+), HGF(-)) and KP4 (c-Met(+), HGF(+)) cells. As BxPC-3 cells are responsive to exogenous HGF, s.c. tumor xenografts were grown in a paracrine manner with purified human HGF provided by osmotic pumps, wherein MetMAb treatment significantly inhibited tumor growth. KP4 cells are autocrine for HGF and c-Met, and MetMAb strongly inhibited s.c. tumor growth. To better model pancreatic cancer and to enable long-term survival studies, an orthotopic model of KP4 was established. MetMAb significantly inhibited orthotopic KP4 tumor growth in 4-week studies monitored by ultrasound and also improved survival in 90-day studies. MetMAb significantly reduced c-Met phosphorylation in orthotopic KP4 tumors with a concomitant decrease in Ki-67 staining. These data suggest that the HGF/c-Met axis plays an important role in the progression of pancreatic cancer and that targeting c-Met therein may have therapeutic value.

Divalent cations modulate the integrin-mediated malignant phenotype in pancreatic cancer cells

We have previously demonstrated that pathophysiological shifts in the concentrations of extracellular Mg(2+) and Ca(2+) activate the alpha(2)beta(1) integrin-mediated malignant phenotype on type I collagen in pancreatic cancer cells, as evidenced by increased adhesion, migration and proliferation. In the present study, we examined the integrin and divalent cation specificity of pancreatic cancer cell interactions with other physiologically relevant extracellular matrix proteins, including fibronectin, type IV collagen, laminin and vitronectin. Our results indicate that, like alpha(2)beta(1) integrin-mediated interactions with type I collagen, beta(1) integrin-mediated adhesion to fibronectin, type IV collagen and laminin are promoted by Mg(2+) but not by Ca(2+). On vitronectin, cells attach via alpha(v)beta(5) and beta(1) integrins, and in the presence of either divalent cation. We also demonstrate that, like type I collagen, pancreatic cancer cell migration and proliferation on fibronectin, laminin and type IV collagen is maximal when Mg(2+) is present at concentrations that promote optimal adhesion and Ca(2+) is present at concentrations less than Mg(2+). On vitronectin, Panc-1 cell migration is maximal with decreased Mg(2+) and increased Ca(2+), but the reverse is true for BxPC-3 cells. Both cell lines exhibited maximal proliferation with increased Mg(2+) and decreased Ca(2+), however. Together with evidence indicating that the in vivo local tumor microenvironment contains increased Mg(2+) and decreased Ca(2+), our studies demonstrate that such divalent cation shifts could activate the integrin-mediated malignant phenotype in pancreatic cancer.

Cachexia worsens prognosis in patients with resectable pancreatic cancer

INTRODUCTION

Pancreatic cancer is the fourth leading cause of cancer-related death in Western countries with a poor prognosis (5-year survival rates, 25% in patients after tumor resection with adjuvant treatment; overall, the 5-year survival rate is about 4%; Jemal et al., CA Cancer J Clin, 55:10-30, 2005). Many patients develop a cachectic status during the progression of the disease, and this syndrome accounts for up to 80% of deaths in patients with advanced pancreatic cancer. Remarkably, there are only a few data available on the impact of cachexia in patients with pancreatic cancer scheduled for tumor resection.

MATERIAL AND METHODS

Therefore, in this study, 227 consecutive patients with ductal adenocarcinoma of the pancreas were documented over an 18-month period regarding the prevalence of cachexia and its influence on perioperative morbidity and mortality with a special interest to postoperative weight gain and survival in a prospectively designed database and followed up.

RESULTS

In 40.5% of the patients, cachexia was already present at the time of operation. The cachectic patients did present in a worse nutritional status, represented by lower protein, albumins, and hemoglobin levels. Despite no significant differences in tumor size, lymph node status, and CA19-9 levels, the resection rate in patients with cachexia was reduced (77.8% vs. 48.9%) due to a higher rate of metastatic disease in patients with cachexia. The morbidity and in-hospital mortality revealed no significant difference. However, patients with and without cachexia lost weight after operation, and the weight gain started not until 6 months after operation. The survival in patients with cachexia was significantly reduced in patients undergoing tumor resection as well as in palliative treated patients.

CONCLUSION

Cachexia has a significant impact on survival and performance status in palliative patients as well as in patients operated for pancreatic cancer. But tumor-related cachexia is not necessarily dependent on tumor size or load and that metastatic dedifferentiation of the tumor might be a critical step in the development of tumor-associated cachexia.

Activation of the alpha2beta1 integrin-mediated malignant phenotype on type I collagen in pancreatic cancer cells by shifts in the concentrations of extracellular Mg2+ and Ca2+

The authors have previously demonstrated that alpha(2)beta(1) integrin-mediated pancreatic cancer cell adhesion to Type I collagen is Mg(2+)-dependent, inhibited by Ca(2+), and that this integrin, purified from cell lysates using Type I-collagen-sepharose in Mg(2+), can be eluted with Ca(2+). In the present study, the authors examined the divalent cation-dependency of alpha(2)beta(1) integrin-mediated pancreatic cancer cell adhesion, migration and proliferation on Type I collagen, an extracellular matrix protein shown to be highly up-regulated, and to promote the malignant phenotype in vitro and in vivo. The results indicate that cells attach to Type I collagen maximally when Mg(2+) is greater than 1 mM, and that addition of increasing concentrations of Ca(2+) reduces this adhesion. These effects are reversible, in that previous cell attachment in Mg(2+) can be reversed by adding Ca(2+), and vice versa. They also demonstrate that pancreatic cancer cells migrate and proliferate on Type I collagen in Mg(2+) alone, but maximally when Mg(2+) is present at concentrations that promote maximal cell adhesion and Ca(2+) is present at concentrations less than Mg(2+). Cell adhesion and proliferation assays, as well as affinity chromatography on Type I collagen using anti-integrin function-blocking monoclonal antibodies indicate that the effects of these divalent cation shifts are mediated specifically by the alpha(2)beta(1) integrin. As pancreatic juice contains over 1,200-fold more Mg(2+) than Ca(2+) and solid tumors are characterized by increased magnesium load, these data indicate that such pathophysiological divalent cation shifts could be involved in the activation of the alpha(2)beta(1) integrin-mediated malignant phenotype on Type I collagen in the pancreatic cancer.

Using metastasis suppressor proteins to dissect interactions among cancer cells and their microenvironment

Cancer metastasis is a complex, dynamic process that begins with dissemination of cells from the primary tumor and culminates in the formation of clinically detectable, overt metastases at one or more discontinuous secondary sites. Evidence from in vivo video microscopy as well as PCR and immunohistochemical studies suggest that cancer cell dissemination is an early event in tumor progression and that cells may persist in a potentially dormant state for a prolonged period. Similarly, the mechanisms by which these disseminated cells initiate growth and complete the process of metastatic colonization remain largely unknown. Understanding signal transduction pathways regulating this final step of metastasis is therefore critical for successful clinical management. While genetic mutations or epigenetic changes may be required for a cell or group of cells to separate and survive distant from the primary tumor, the microenvironment within secondary tissues plays a substantial role in influencing whether disseminated cells survive and proliferate. Our work is focused on using metastasis suppressor proteins to gain insight into why the majority of disseminated cells, which should be fully malignant, do not proliferate immediately at secondary sites. The translational goal of this work is to identify targets for inhibiting metastatic growth and prolonging disease-free survival.

Long-term results after intraoperative radiation therapy for gastric cancer

PURPOSE

We retrospectively analyzed the impact of intraoperative radiation therapy (IORT) on long-term survival in patients with resectable gastric cancer.

METHODS AND MATERIALS

From 1991 to 2001, a total of 84 patients with gastric neoplasms underwent gastectomy or subtotal resection with IORT (23 Gy, 6-15 MeV; IORT-positive [IORT(+)] group). Patients with a history of additional neoadjuvant chemotherapy, histologically confirmed R1 or R2 resection, or reoperation with curative intention after local recurrence were excluded from further analysis. The remaining 61 patients were retrospectively matched with 61 patients without IORT (IORT-negative [IORT(-)] group) for Union Internationale Contre le Cancer (UICC) stage, patient age, histologic grading, extent of surgery, and level of lymph node dissection. Subgroups included postoperative UICC Stages I (n = 31), II (n = 11), III (n = 14), and IV (n = 5).

RESULTS

Mean follow-up was 4.8 years in the IORT(+) group and 5.0 years in the IORT(-) group. The overall 5-year patient survival rate was 58% in the IORT(+) group vs. 59% in the IORT(-) group (p = 0.99). Subgroup analysis showed no impact of IORT on 5-year patient survival for those with UICC Stages I/II (76% vs. 80%; p = 0.87) and III/IV (21% vs. 14%, IORT(+) vs. IORT(-) group; p = 0.30). Perioperative mortality rates were 4.9% and 4.9% in the IORT(+) vs. IORT(-) group. Total surgical complications were more common in the IORT(+) than IORT(-) group (44.3% vs. 19.7%; p < 0.05). The locoregional tumor recurrence rate was 9.8% in the IORT(+) group.

CONCLUSIONS

Use of IORT was associated with low locoregional tumor recurrence, but had no benefit on long-term survival while significantly increasing surgical morbidity in patients with curable gastric cancer.

Application of surface-enhanced laser desorption/ionization time-of-flight mass spectrometry for early detection of pancreatic cancer

Pancreatic cancer is a devastating and lethal disease. Early detection continues to be a serious, unsolved problem. However, proteomics is emerging as a powerful new tool for the diagnosis of pancreatic cancer. Surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF MS) is a new technique that allows for rapid high-throughput screening of protein expression in clinical samples. The progress and challenges in applying SELDI-TOF MS to protein biomarker discovery in pancreatic cancer are reviewed in this paper.

Clinical implications of peritoneal cytology in potentially resectable pancreatic cancer: positive peritoneal cytology may not confer an adverse prognosis

OBJECTIVES

To determine the value of peritoneal washing cytology (CY) in determining resectability of pancreatic cancer.

SUMMARY BACKGROUND DATA

CY has been used widely in the diagnosis and staging of several cancers. However, its predictive value in identifying potentially resectable pancreatic cancer is undetermined.

METHODS

Peritoneal washing samples were collected from 233 patients with pancreatic cancer between June 1991 and August 2006. A total of 157 patients had resectable and 76 had unresectable lesions. Correlations between CY status and clinicopathologic parameters with overall survival rates were analyzed.

RESULTS

Malignant cells were identified in samples from 21 patients (13.4%) with resectable tumors and 27 patients (35.5%) with unresectable tumors. CY+ was more frequent in large tumors (> or =2 cm) than small tumors (<2 cm; P = 0.034). CY status did not correlate with any other clinicopathologic parameter. The overall survival of CY+ patients was worse than that of CY- patients (P = 0.047). Median survival following resection was 13.6 months for CY+ patients and 13.5 months for CY- patients. Among the patients who had unresectable lesions, median survival time was 5.9 months for CY+ and 6.1 months for CY- patients. However, among CY+ patients, those who underwent resection lived longer than those who did not (P = 0.019).

CONCLUSIONS

Cytologic status has little predictive value for survival, and patients whose pancreatic cancer would otherwise be considered resectable should not be denied curative resection solely because they are CY+.

Medical treatment of pancreatic cancer

Pancreatic carcinoma is a devastating disease with the worst prognosis of all solid tumors; the only cure is surgery. The vast majority of patients are inoperable at the time of diagnosis and require palliative treatment. With a median survival time oscillating around 6 months, indicating an almost complete resistance to conventional cytotoxic and radiation therapy, there is ample room for improvement. Therefore, pancreatic carcinoma has been used to trial many new substances and novel concepts. All aspects of palliative antitumor treatment will be presented in detail and discussed. Finally, some outlooks are given into the future of pancreatic cancer treatment.

Preventing liver metastasis by resecting the primary pancreatic carcinoma at an early stage of intrapancreatic transplantation in hamsters

PURPOSE

To determine whether early primary pancreatic tumor resection can prevent liver metastases of intrapancreatic transplantation in a hamster model.

METHODS

Cells from the PGHAM-1 cell line were transplanted into the pancreases of 30 Syrian golden hamsters. A suspension of 5 x 10(6) cells was injected into the splenic lobe of each pancreas. The primary pancreatic tumor was resected in 15 of the hamsters 10 days after transplantation (resection group). Fifteen other animals with transplantation but without resection served as controls (control group). All hamsters were killed 21 days after transplantation. The primary pancreatic tumors were measured for size and volume and examined histologically and immunohistologically for angiogenesis and tumor proliferation.

RESULTS

In the resection group, small pancreatic tumors 4.7 +/- 0.94 mm in diameter were found and resected 10 days after transplantation. Neither pancreatic tumors nor liver metastases were found in the resection group at the end of the experiment. All animals in the control group had pancreatic tumors 12.3 +/- 3.29 mm in size, and 11 of 15 (73.3%) had liver metastases. The primary pancreatic tumors in the group with liver metastasis were significantly larger in diameter and volume than those in this group without liver metastasis (p<0.01). In the control group, proliferation of the primary pancreatic tumor, evaluated according to argyrophilic nucleolar organizer region, showed no differences within the pancreatic tumor group. On the other hand, the microvessel density of pancreatic tumors with liver metastases was significantly higher than that of tumors without liver metastases.

CONCLUSIONS

Our results suggest that 10 days after transplantation, the pancreatic tumors were small in size and volume and ready to proliferate but not yet ready to begin metastasizing through angiogenesis. This is one reason why early resection of the primary tumor prevents liver metastasis.