Clinical usefulness of 18-fluorodeoxyglucose positron emission tomography in the management of patients with nonpancreatic periampullary neoplasms

BACKGROUND

18-Fluorodeoxyglucose positron emission tomography (18-FDG PET) has been investigated for the diagnosis and staging of gastrointestinal malignancies including pancreatic adenocarcinoma. The aim of this study was to examine the clinical usefulness of 18-FDG PET in the diagnosis and follow-up evaluation of patients with periampullary neoplasms.

METHODS

Twenty-five patients underwent whole-body 18-FDG PET and abdominal computed tomography (CT). Pathologic confirmation was obtained in all patients by surgical resection or biopsy examination. The 18-FDG PET was analyzed visually and semiquantitatively using the standard uptake value (SUV). Positivity was assumed when a focal uptake occurred with an SUV of 2.5 or greater.

RESULTS

Between January 1998 and December 2003, 14 ampullary, 7 bile duct, and 4 duodenal tumors were included in the study. PET showed increased focal uptake in 22 patients (88%): 11 of 14 (79%) ampullary tumors, and 100% of bile duct and duodenal tumors. PET showed a focal uptake in 11 of 12 patients without detectable mass at CT scan, and lymph node metastases in 6 patients. An SUV value of 2.7 discriminated adenomas or noninvasive cancers (n = 6) from invasive malignancies (n = 14). Follow-up evaluation including CT scan and PET was performed in 12 patients: PET showed recurrent disease not seen by CT in 4 patients, confirmed CT findings in 6 patients, and showed an unsuspected primary lung cancer in 1 patient and colon cancer in another patient.

CONCLUSIONS

18-FDG PET is very sensitive for detecting periampullary neoplasms. It may be useful to differentiate benign or borderline lesions from invasive tumors when no mass has been identified by traditional imaging. Finally, it is very useful in the follow-up evaluation of resected patients to identify recurrent disease or other malignancies.

Pancreatic cancer cells invasiveness is mainly affected by interleukin-1beta not by transforming growth factor-beta1

BACKGROUND

We investigated in vitro whether IL-1beta and TGF-beta1 affect pancreatic cancer cell growth, adhesion to the extracellular matrix and Matrigel invasion.

MATERIALS AND METHODS

Adhesion to fibronectin, laminin and type I collagen, and Matrigel invasion after stimulation with saline, IL-1beta and TGF-beta1 were evaluated using three primary and three metastatic pancreatic cancer cell lines.

RESULTS

Extracellular matrix adhesion of control cells varied independently of the metastatic characteristics of the studied cell lines, whereas Matrigel invasion of control cells was partly correlated with the in vivo metastatic potential. IL-1beta did not influence extracellular matrix adhesion, whereas it significantly enhanced the invasiveness of three of the six cell lines. TGF-beta1 affected the adhesion of one cell line, and exerted contrasting effects on Matrigel invasion of different cell lines.

CONCLUSIONS

IL-1beta enhances the invasive capacity of pancreatic cancer cells, whereas TGF-beta1 has paradoxical effects on pancreatic cancer cells; this makes it difficult to interfere with TGF-beta1 signaling in pancreatic cancer treatment.

Decreased total lymphocyte counts in pancreatic cancer: an index of adverse outcome

OBJECTIVES

An impaired host immunity might concur in determining the dismal prognosis of patients with pancreatic cancer (PC). Our aim was to ascertain whether the immunophenotype pattern of blood lymphocytes in PC correlates with tumor stage, grade, or survival.

METHODS

We studied 115 patients with PC, 44 with chronic pancreatitis (CP), 23 with tumors of the pancreatico-biliary tract, and 34 healthy controls (CS). Survival data were available for 77 patients with PC. Lymphocyte subsets were determined by fluorescent activated cell sorter (FACS) analysis.

RESULTS

In patients with PC, total lymphocyte counts were lower than in CP or CS, and CD8 lymphocyte subset levels were higher with respect to CS. Lower circulating lymphocytes were found in advanced PC stages (IIB-IV; chi2 = 11.55, P < 0.05) compared with stages 0 to IIA. Cox regression analysis, made considering total lymphocyte counts and tumor stage as covariates, was found to be significant for both tumor stage (P < 0.001) and total lymphocyte counts (P < 0.05).

CONCLUSIONS

The reduction of total lymphocytes in blood is the main immunologic change in advanced PC. The survival of these patients depends mainly on tumor stage, but it is also affected by the number of circulating lymphocytes, suggesting that the immune system plays an important role in pancreatic adenocarcinoma immunosurveillance and immunoediting.

Extent of lymphadenectomy in the resection of pancreatic cancer. Analysis of the existing evidence

Pancreaticoduodenectomy is considered the standard procedure for the surgical treatment of the pancreatic head cancer. However, the extent of lymph node clearance associated to the procedure is still largely debated. Arguments in favour of an extended lymphadenectomy are the regular progression of lymph node invasion, without skip metastases, and the removal of the extrapancreatic neural plexus that is invaded in 52-72% of patients. Arguments against the extended lymphadenectomy are the failure of extended lymphadenectomy to improve survival in other cancers, and the severe diarrhoea that follows the skeletonisation of the superior mesenteric artery. After Ishikawa's paper, several retrospective studies supported a longer survival after an extended than after a standard lymphadenectomy, but as much retrospective studies failed to demonstrate any difference. Only three prospective randomised controlled trials have been performed so far. Unfortunately all are underpowered, and the substantial differences in the surgical procedures, in the adjuvant treatment, and in the length of follow-up make the comparison impossible. Only one study reports a significantly longer survival for lymph node positive patients who underwent an extended lymphadenectomy, but adjuvant treatment was not performed. Furthermore, the difference was of minimal clinical impact. At least two adequately powered prospective Randomised Controlled Trials including a true extended lymphadenectomy, and a standardised adjuvant treatment, would be required to answer the question. Unfortunately, we have not yet a standardised adjuvant (or neoadjuvant) treatment, and we do not know the impact of such treatment on the expected statistical difference in the survival after a standard or extended lymphadenectomy. The lot of work required to perform such trials probably doesn't worth the expected results.

Clinical and diagnostic aspects of cystic insulinoma

Cystic endocrine tumors of the pancreas rarely occur, and only a few cases of cystic insulinoma have been reported to date. Diagnosis of insulinoma could be difficult if the functional activity is incomplete, possibly leading to blunted symptoms of hypoglycemia and failure in the laboratory to provide evidence of hyperinsulinemia. We report a clinical case of cystic insulinoma confirmed by histological examination after surgery, characterized by a high intracystic insulin concentration despite normal blood basal levels of the hormone. New diagnostic findings from dynamic tests and cystic fluid examination have been carefully focused on.

Pancreatic cancer-associated diabetes mellitus: an open field for proteomic applications

BACKGROUND

Diabetes mellitus is associated with pancreatic cancer in more than 80% of the cases. Clinical, epidemiological, and experimental data indicate that pancreatic cancer causes diabetes mellitus by releasing soluble mediators which interfere with both beta-cell function and liver and muscle glucose metabolism.

METHODS

We analysed, by matrix-assisted laser desorption ionization time of flight (MALDI-TOF), a series of pancreatic cancer cell lines conditioned media, pancreatic cancer patients' peripheral and portal sera, comparing them with controls and chronic pancreatitis patients' sera.

RESULTS

MALDI-TOF analysis of pancreatic cancer cells conditioned media and patients' sera indicated a low molecular weight peptide to be the putative pancreatic cancer-associated diabetogenic factor. The sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis of tumor samples from diabetic and non-diabetic patients revealed the presence of a 1500 Da peptide only in diabetic patients. The amino acid sequence of this peptide corresponded to the N-terminal of an S-100 calcium binding protein, which was therefore suggested to be the pancreatic cancer-associated diabetogenic factor.

CONCLUSIONS

We identified a tumor-derived peptide of 14 amino acids sharing a 100% homology with an S-100 calcium binding protein, which is probably the pancreatic cancer-associated diabetogenic factor.

Killer genes in pancreatic cancer therapy

This review describes: 1. The main genetic alterations found in pancreatic cancer (EGF-R overexpression, SST-2 somatostatin receptor loss of expression, k-ras, p53 mutations and DPC4 mutations) and the effect of their replacements by gene therapy on tumor growth; 2. The use of suicide genes (HSV-TK and CD) for pancreatic cancer gene therapy in vitro and in vivo; 3. The implications for pancreatic cancer treatment when using cytotoxic bacterial toxins; 4. Viral and non-viral delivery systems for the transfer of therapeutical genes into pancreatic cancer cells. Overall both the correction of pancreatic cancer cells main genetic alterations and the use of suicide genes allow only partial tumor regression in vitro and in vivo. The lack of a 100% effect for any studied strategy considered alone, indicates the need for combined therapies to achieve a satisfactory treatment of this tumor.

[Enucleation-resection of pancreatic neuroendocrine tumors: 25 years of experience]

From 1980 to 2004, out of 109 patients who underwent surgery for neuroendocrine pancreatic tumor, 33 had a simple tumor excision. Seventy-two percent of cases were insulinomas. Age, sex, site and size of the tumor, associated diseases, hospital stay and complications were retrospectively reviewed by the clinical records. Patients (12 males and 21 females) averaged 56.8 years, range 20-86. Mean size of the tumor was 1.7 cm and 54.5% were in the pancreatic head; 78.8% of cases had medical associated diseases. Hospital stay was 12 days (median; range, 6-81 days) and mean period of gastric suction was 4 days. Forty-eight percent had a uneventful postoperative course. Complications were divided in early (related to pancreatic surgery, related to general open surgery and medical) and late events. Complication related to pancreatic surgery were 6/33 (18%); 5 pancreatic fistulas (4 low output) and 1 acute pancreatitis, while 5/33 had a general surgery complication (2 leacking due to gastric and duodenal associated operations). Medical complications were recorded in 13 cases. Late complications occurred in 4 cases (2 incisional hernias, 1 pseudocyst and 1 keloid). No patient was re-operated for pancreatic complications; 1 was reoperated for evisceration and 1 for hyper-parathyroidism in the early post-operative period. No mortality occurred. Re-evaluation of the clinical records in order to be submitted to laparoscopic surgery excluded 17/33 cases (51%) as candidate to laparoscopic approach.

[Positron emission tomography with fluorodeoxyglucose in gastro-entero-pancreatic tumors: diagnostic role and prognostic implications]

From November 1994 to November 2004, seventy-seven patients with neuroendocrine gastro-entero-pancreatic tumor (71% pancreatic) were investigated with 18-fluorine-deoxi-glucose positron emission tomography (FDG-PET). PET results were compared with CT-scan, MRI and octreoscan scintigraphy and clinico-pathologic features of patients and survival. Overall PET sensitivity was 57%; 78% of malignant tumors, 67% of borderline and 17% of benign tumors were detected by FDG-PET. No duodenal tumor was detected by PET scan. Only 16% of primary less than 2 cm in size was localized. In 16% of cases PET scan provided new information able to change therapeutic management. In PET positive patients the addictive information obtained by PET scan when compared with octreoscan, MRI and CT scan were respectively 50% more, 26% more and 30% more. In malignant neuroendocrine tumors PET positivity was related to short survival. No patient with malignant tumor died for disease progression in the follow-up when PET was negative, while 13/35 PET positive patients died (p <0.003). FDG-PET proved to be a second line technique in neuroendocrine digestive tumors. PET results improve clinical staging of disease and is related to survival in malignant cases; in 16% of cases may change the therapeutic option.

F-18-fluorodeoxyglucose positron emission tomography in differentiating malignant from benign pancreatic cysts: a prospective study

The differential diagnosis between benign and malignant pancreatic cystic lesions may be very difficult. We recently found that F-18-fluorodeoxyglucose positron emission tomography (18-FDG PET) was useful for the preoperative work-up of pancreatic cystic lesions. This study was undertaken to confirm these results. From February 2000 to July 2003, 50 patients with a pancreatic cystic lesion were prospectively investigated with 18-FDG PET in addition to helical computed tomography (CT) and, in some instances, magnetic resonance imaging (MRI). The validation of diagnosis was based on pathologic findings after surgery (n=31), percutaneous biopsy (n=4), and according to follow-up in 15 patients. The 18-FDG PET was analyzed visually and semiquantitatively using the standard uptake value (SUV). The accuracy of FDG PET and CT was determined for preoperative diagnosis of malignant cystic lesions. Seventeen patients had malignant cystic lesions. Sixteen (94%) showed increased 18-FDG uptake (SUV>2.5), including two patients with carcinoma in situ. Eleven patients (65%) were correctly identified as having malignancy by CT. Thirty-three patients had benign tumors: two patients showed increased 18-FDG uptake, and four patients showed CT findings of malignancy. Sensitivity, specificity, positive and negative predictive value, and accuracy of 18-FDG PET and CT in detecting malignant tumors were 94%, 94%, 89%, 97%, and 94% and 65%, 88%, 73%, 83%, and 80%, respectively. 18-FDG PET is accurate in identifying malignant pancreatic cystic lesions and should be used in combination with CT in the preoperative evaluation of patients with pancreatic cystic lesions. A negative result with 18-FDG PET may avoid unnecessary operation in asymptomatic or high-risk patients.

Maldi-TOF analysis of portal sera of pancreatic cancer patients: identification of diabetogenic and antidiabetogenic peptides

BACKGROUND

Pancreatic cancer (PC) associated diabetes mellitus (DM) might be consequent to the diabetogenic effects of tumour products, possibly acting via nitric oxide (NO). Our aims were: (1) to verify whether PC associated DM determines an increased hepatic NO and (2) using MALDI-TOF analysis, to evaluate the peptide composition of PC cell conditioned media (CM) and of portal sera from patients with PC with (n=7) or without (n=4) DM.

METHODS

In liver tissue homogenates of 23 patients with PC (n=17) or chronic pancreatitis (n=6) GAPDH mRNA and activity, glucose, lactate, nitrite and nitrate were assayed. MALDI-TOF analysis was performed in three PC cell lines CM, and in portal sera from patients with PC.

RESULTS

Higher GAPDH mRNA and nitrite were found in patients with than in patients without DM. In PC cell CM, only 9 among a total of 75 fragments identified, were tumour specific. One hundred seventy-three fragments were identified in the portal sera of patients: one was positively and six fragments were negatively correlated with DM.

CONCLUSIONS

Unlike liver GAPDH, NO appears to be involved in PC associated DM. In portal sera, the absence, rather than the presence, of specific fragments, appears to be correlated with the development of DM.

Altered glucose metabolism and proteolysis in pancreatic cancer cell conditioned myoblasts: searching for a gene expression pattern with a microarray analysis of 5000 skeletal muscle genes

BACKGROUND AND AIMS

We verified whether conditioned media (CM) from pancreatic cancer cell lines (MIAPaCa2, CAPAN-1, PANC-1, BxPC3) alter glucose metabolism and gene expression profiles (microarray experiment with a platform of 5000 skeletal muscle cDNA) in mice myoblasts.

METHODS

Myoblasts were incubated with control or pancreatic cancer CM for 24 and 48 hours.

RESULTS

Lactate significantly increased in CM compared with non-conditioned myoblasts. No variations in expression levels of the main genes involved in glycolysis were found in CM myoblasts. Propionyl coenzyme A carboxylase and isocitrate dehydrogenase 3 beta genes, which encode enzymes of the tricarboxylic acid cycle, were overexpressed, while IGFIIR and VAMP5 genes were underexpressed in CM myoblasts. PAFAH1B1 and BCL-2 genes (intracellular signal transduction) and the serine protease cathepsin G (proteolysis), were overexpressed in CM myoblasts. Tyrosine accumulation in CM myoblasts suggested that proteolysis overcomes protein synthesis. Sorcin, actin alpha, troponin T1, and filamin A were underexpressed in CM myoblasts.

CONCLUSIONS

Our findings demonstrate that pancreatic cancer cell conditioned media enhanced lactate production and induced proteolysis, possibly by altering expression levels of a large number of genes, not only those involved in protein biosynthesis and degradation or glucose metabolism, but also those involved in the tricarboxylic acid cycle and in vesicle traffic.

Adenocarcinoma of the pancreas: the rationale for neoadjuvant therapy

The survival of patients with pancreatic cancer is dismal: tumor's resection is possible in only 10-20% of patients. This has prompted clinical studies with chemotherapy and/or radiotherapy designed to increase the number of patients eligible for surgery, to maximize local tumor control and to improve the length of survival. Since postoperative chemoradiation is often delayed in these patients due to morbidity and prolonged recovery time associated with surgery, investigators are assessing the efficacy of chemoradiation before pancreatic resection in patients with potentially resectable pancreatic carcinoma or the potential to downstage locally advanced pancreatic cancer to resectable tumor. The analysis of several clinical trials published so far shows that results are conflicting and not definitive. No randomized clinical studies have been reported. Moreover, neoadjuvant therapy rarely leads to surgical downstaging allowing for potentially curative pancreatic resections. Novel multimodality approaches are required, and patients should be entered on clinical, controlled trials.

Suicide gene therapy with HSV-TK in pancreatic cancer has no effect in vivo in a mouse model

AIM

To study in vivo whether pancreatic cancer tumour growth and metastasis can be modified by a gene construct with HSV-TK suicide gene and IL2 co-expression.

METHODS

Seventy-eight female SCID mice were i.p. inoculated with retrovirally transduced or control MIA PaCa 2, CAPAN-1 and PANC-1 cell lines. The animals were then randomly selected for saline or ganciclovir (GCV) treatment from the second week, for a total of two weeks.

RESULTS

Most inoculated mice developed tumour nodules and spleen metastases. The liver was colonized by control CAPAN-1 and MIA PaCa 2, but not by PANC-1. Tumours in transduced MIA PaCa 2 cell injected mice were smaller, and in transduced CAPAN-1 injected mice larger, than in control-inoculated mice. There were increased pancreatic and decreased spleen metastases from transduced CAPAN-1, and diminished liver involvement from transduced MIA PaCa 2. No differences were found between mice inoculated with transduced and control PANC-1 cell lines. GCV treatment had no effect on tumour's size or metastases.

CONCLUSIONS

The HSV-TK suicide gene does not confer GCV sensitivity to pancreatic cancer in this in vivo model. Different pancreatic cancer cell lines cause different growth and metastasis patterns after inoculation in SCID mice, possibly because of variations in their inherent characteristics. The different effects of our vector on cell growth and metastasis may be attributable to the effects of the immunostimulatory cytokine IL2.

18-Fluorodeoxyglucose positron emission tomography in predicting survival of patients with pancreatic carcinoma

The prediction of survival of patients with pancreatic cancer is usually based on tumor staging and grading and on the level of tumor markers. However, accurate tumor staging can be obtained only after resection, and still there is a great difference in survival rates among patients with the same clinicopathologic parameters. Recently the uptake of 18-fluorodeoxyglucose (FDG) by positron emission tomography (PET) has been found to be correlated with survival in patients with pancreatic cancer. This study evaluated the role of 18FDG PET as a prognostic factor for patients with pancreatic cancer. From June 1996 to July 2002, a total of 118 patients underwent PET for pancreatic cancer. The standardized uptake value (SUV) of 18FDG was calculated in 60 of them, and these patients were divided into high (>4) and low (< or =4) SUV groups. They were also evaluated according to the tumor node metastasis (TNM) classification system of the International Union Against Cancer, and by tumor grade, medical or surgical treatment, diabetes, age, sex, and CA 19-9 serum levels. Twenty-nine cancers showed high and 31 showed low SUVs. Survival was significantly influenced by tumor stage (P=0.0001), tumor grade (P=0.01), and SUV (P=0.005). Multivariate analysis showed that only stage (P=0.001) and SUV (P=0.0002) were independent predictors of survival. When patients who were analyzed for SUV were stratified according to the other variables, FDG uptake was related to survival also after stratification for the following: stage III to IVa (P=0.002), stage IVb (P=0.01), tumor resection (P=0.006), moderately differentiated tumors (P=0.01), age less than 65 years (P=0.006), CA 19-9 levels greater than 300 kU/L (P=0.002), and absence of diabetes (P=0.0001). The SUV calculated with 18FDG PET is an important prognostic factor for patients with pancreatic cancer and may be useful in selecting patients for therapeutic management.

Pancreatic resection for metastatic tumors to the pancreas

BACKGROUND AND OBJECTIVES

The incidence of metastases to the pancreas is very low. The benefit of resection of pancreatic metastasis is poorly defined. In this review we evaluated the outcome of patients undergoing pancreatic resection for metastatic tumors to the pancreas.

METHODS

Eight patients underwent pancreatic resection for metastatic tumor from December 1980 to June 2001. The primary cancer was colon carcinoma (n = 4), renal cell cancer (n = 2), duodenal leiomyosarcoma (n = 1), and malignant fibrous histiocytoma (n = 1). The median interval between primary treatment and detection of pancreatic metastases was 36 months. In two cases pancreatic metastases were synchronous with the primary tumor.

RESULTS

Four patients underwent pancreatoduodenectomy, two distal pancreatectomy, one total pancreatectomy, and one median pancreatectomy. Associated resection of extrapancreatic lesions was performed in four patients, including two left hepatectomy and two left colectomy. There was no postoperative mortality, but two patients had a pancreatic and a biliary fistula, respectively. Survival averaged 23 months (range 14-42 months): four patients died for metastatic disease from 14 to 42 months after operation, while four patients are alive and well 14 to 31 months after surgery.

CONCLUSIONS

Pancreatic resection for metastatic disease to the pancreas should be considered even in selected patients with limited extrapancreatic disease. Long-term survival or good palliation may be achieved.

Role of surgery in the treatment of bilio-pancreatic cancer: the European experience

Pancreatic cancer is the eighth most common cancer in Europe, accounting for 4.1% of cancer deaths in men and 4.8% in women. Standardized pancreatoduodenectomy and left pancreatectomy are the gold standard for routine surgical treatment of pancreatic cancer. Total pancreatectomy should be reserved for positive pancreatic resection margins or severe pancreatic anastomotic leak; mesenterico-portal vein resection should be performed only when it is the only reasonable way to obtain clear margins. Extended lymphadenectomies are recommended only in prospective, randomized studies. Ongoing efforts to standardize surgical procedures will facilitate comparison of selection criteria and trial data among different centers, and will also optimize the study design of ongoing/planned prospective trials using adjuvant and neoadjuvant chemoradiotherapy in pancreatic cancer.

Epidemiology of pancreatic cancer in Northeastern Italy: incidence, resectability rate, hospital stay, costs and survival (1990-1992)

BACKGROUND

The incidence of pancreatic cancer and relative hospital stay and costs are not well known.

AIMS

To define the incidence, hospital stay and cost of pancreatic cancer in a well-defined area of Italy.

PATIENTS AND METHODS

Each new case of pancreatic cancer diagnosed between 1990 and 1992 among 669,703 inhabitants in the Veneto Region of Northern Italy was recorded and followed until death or for 5 years after diagnosis. Four types of hospital stay were defined. Type 1: undiagnosed pancreatic cancer; type 2: first diagnosis of pancreatic cancer, treatment excluded; type 3: main treatment; and type 4: follow-up and disease-related complications. Data were analysed for hospital stay-related procedures, costs and survival.

RESULTS

Pancreatic cancer was diagnosed in 253 patients (12.6/100,000 per year), 43 patients (17.7%) underwent surgical resection, and 93 (36.8%) palliative surgery. The mean duration of type 3 hospital stay was similar for resection, palliative and exploratory surgery. The estimated hospital cost was significantly higher for surgical resection, almost the same for palliative and exploratory surgery, and only slightly lower for medical treatment. Each patient spent a mean of 57.7 days in the hospital. The hospital mortality rate was 4.6% for surgical resection, 22.1% for palliative surgery, and 18.7% for exploratory laparotomy. Overall, the 1-, 2-, 3- and 5-year survival rates were 20.9%, 5.1%, 2.9% and 1.2%, respectively.

CONCLUSIONS

Pancreatic cancer is an expensive, almost incurable disease. Integrated treatments in specialized Centres should reduce the mortality rate and costs.

Retrovirus-mediated herpes simplex virus thymidine kinase gene transfer in pancreatic cancer cell lines: an incomplete antitumor effect

INTRODUCTION

The transfer of drug-susceptible (suicide) genes to tumor cells by retroviral or adenoviral vectors is a novel approach to the treatment of human tumors.

AIMS

To ascertain the antitumor effect of retroviral transduction of the pancreatic cancer cell lines MIA PaCa 2, CAPAN-1, PANC1, and PSN1 with the herpes simplex virus thymidine kinase (HSV-TK) gene.

METHODOLOGY

The vector carried a neoselectable marker gene, the human interleukin-2 gene, an internal ribosome entry coding site, and the region coding HSV-TK.

RESULTS

Twenty micromoles or less of ganciclovir did not modify nontransduced TK- cell growth, whereas > or =100 micromol completely inhibited TK- cell growth, indicating that this dosage is cytotoxic per se. The 4 TK- and the 4 transduced cell lines were treated daily with 0.001, 0.01, 0.1, 1, 10, and 20 micromol of ganciclovir for 13 days. CAPAN-1 cell growth was completely inhibited by 0.1 micromol of ganciclovir; higher doses were required to kill PANC1 (10 micromol) and PSN1 (20 micromol). MIA PaCa 2 cell growth decreased following a 20-micromol ganciclovir dosing. The bystander effect was great in the CAPAN-1 cell line and moderate in PANC1; no bystander effect was recorded in MIA PaCa 2 and PSN1 cell lines.

CONCLUSION

Gene therapy with HSV-TK for pancreatic cancer seems effective in only a limited number of tumor-derived cell lines, and this limits its application in vivo.

Putative pancreatic cancer-associated diabetogenic factor: 2030 MW peptide

INTRODUCTION

Pancreatic adenocarcinoma causes diabetes mellitus by releasing factors interfering with glucose metabolism.

AIMS

We verified in isolated rat hepatocytes the molecular weight (MW) of the fraction from pancreatic cancer cell conditioned media (CM) that altered glucose metabolism and ascertained, using matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) analysis, whether there is any common peptide in CM and in the sera of patients with pancreatic cancer.

METHODOLOGY

Sera was obtained from patients with pancreatic cancer ( n = 14) and chronic pancreatitis ( n = 9) and healthy control subjects ( n = 10). Conditioned medium (CM) was obtained from the following cell lines: MIA PaCa 2, PSK-1, PANC-1, and CAPAN-1. Two fractions (MW of less than 30,000 Da and less than 10,000 Da) were obtained from patients' sera, from CM, and from non-CM (NCM) after two-step ultrafiltration. Rat hepatocytes were incubated with CM and NCM. The peptide profile of patients' sera, CM, and NCM were analyzed using MALDI-MS.

RESULTS

In rat hepatocytes, glucose metabolism was impaired by CM from all the pancreatic cancer cell lines and by CM with an MW of less than 10,000 Da. Two peptides (m/z 2030 and 2726) were found in CM and patients' sera. Only the peptide at m/z 2030 was found to be associated with the presence of diabetes.

CONCLUSION

A peptide at m/z 2030 may be a putative pancreatic cancer-associated diabetogenic factor.

Influence of resection margins on survival for patients with pancreatic cancer treated by adjuvant chemoradiation and/or chemotherapy in the ESPAC-1 randomized controlled trial

OBJECTIVE

To assess the influence of resection margins on survival for patients with resected pancreatic cancer treated within the context of the adjuvant European Study Group for Pancreatic Cancer-1 (ESPAC-1) study.

SUMMARY BACKGROUND DATA

Pancreatic cancer is associated with a poor long-term survival rate of only 10% to 15% after resection. Patients with positive microscopic resection margins (R1) have a worse survival, but it is not known how they fare in adjuvant studies.

METHODS

ESPAC-1, the largest randomized adjuvant study of resectable pancreatic cancer ever performed, set out to look at the roles of chemoradiation and chemotherapy. Randomization was stratified prospectively by resection margin status.

RESULTS

Of 541 patients with a median follow-up of 10 months, 101 (19%) had R1 resections. Resection margin status was confirmed as an influential prognostic factor, with a median survival of 10.9 months for R1 versus 16.9 months months for patients with R0 margins. Resection margin status remained an independent factor in a Cox proportional hazards model only in the absence of tumor grade and nodal status. There was a survival benefit for chemotherapy but not chemoradiation, irrespective of R0/R1 status. The median survival was 19.7 months with chemotherapy versus 14.0 months without. For patients with R0 margins, chemotherapy produced longer survival compared with to no chemotherapy. This difference was less apparent for the smaller subgroup of R1 patients, but there was no significant heterogeneity between the R0 and R1 groups.

CONCLUSIONS

Resection margin-positive pancreatic tumors represent a biologically more aggressive cancer; these patients benefit from resection and adjuvant chemotherapy but not chemoradiation. The magnitude of benefit for chemotherapy treatment is reduced for patients with R1 margins versus those with R0 margins. Patients with R1 tumors should be included in future trials of adjuvant treatments and randomization and analysis should be stratified by this significant prognostic factor.

Value of 18-fluorodeoxyglucose positron emission tomography in the management of patients with cystic tumors of the pancreas

OBJECTIVE

To assess the reliability of 18-fluorodeoxyglucose positron emission tomography (18-FDG PET) in distinguishing benign from malignant cystic lesions of the pancreas.

SUMMARY BACKGROUND DATA

The preoperative differential diagnosis of cystic lesions of the pancreas remains difficult: the most important point is to identify malignant or premalignant cysts that require resection. 18-FDG PET is a new imaging procedure based on the increased glucose metabolism by tumor cells and has been proposed for the diagnosis and staging of pancreatic cancer.

METHODS

During a 4-year period, 56 patients with a suspected cystic tumor of the pancreas underwent 18-FDG PET in addition to computed tomography scanning, serum CA 19-9 assay, and in some instances magnetic resonance imaging or endoscopic retrograde cholangiopancreatography. The 18-FDG PET was analyzed visually and semiquantitatively using the standard uptake value. The accuracy of 18-FDG PET and computed tomography was determined for preoperative diagnosis of a malignant cyst.

RESULTS

Seventeen patients had malignant tumors. Sixteen patients (94%) showed 18-FDG uptake with a standard uptake value of 2.6 to 12.0. Twelve patients (70%) were correctly identified as having malignancy by computed tomography, CA 19-9 assay, or both. Thirty-nine patients had benign tumors: only one mucinous cystadenoma showed increased 18-FDG uptake (standard uptake value 2.6). Five patients with benign cysts showed computed tomography findings of malignancy. Sensitivity, specificity, and positive and negative predictive values for 18-FDG PET and computed tomography scanning in detecting malignant tumors were 94%, 97%, 94%, and 97% and 65%, 87%, 69%, and 85%, respectively.

CONCLUSIONS

18-FDG PET is more accurate than computed tomography in identifying malignant pancreatic cystic lesions and should be used, in combination with computed tomography and tumor markers assay, in the preoperative evaluation of patients with pancreatic cystic lesions. A positive result on 18-FDG PET strongly suggests malignancy and, therefore, a need for resection; a negative result shows a benign tumor that may be treated with limited resection or, in selected high-risk patients, with biopsy, follow-up, or both.

Pancreatic head resection for noninflammatory benign lesions of the head of the pancreas

INTRODUCTION

Duodenum-preserving pancreatic head resection (DPPHR) has been safely performed in patients with chronic pancreatitis. The procedure has rarely been used to remove benign or borderline lesions of the head of the pancreas.

AIMS

To review our experience with 13 patients who underwent DPPHR and to review reports in the literature on the same subject.

METHODOLOGY

From October 1991 to September 2000, 13 patients underwent DPPHR to resect endocrine pancreatic tumors (n = 4), beta cell hyperplasia (n = 1), pancreatic pseudocysts (n = 2), serous cystadenomas (n = 3), congenital (n = 1) and choledochal (n = 1) cysts, and intraductal papillary mucinous tumor (n = 1). The Kocher maneuver was performed in seven patients (group 1) and avoided in six (group 2). Type 1, 2, and 3 DPPHR were defined depending on the amount of pancreatic tissue left at the inner surface of the duodenum. Ten patients underwent evaluation that included an oral glucose tolerance test and exocrine pancreatic function test.

RESULTS

The mortality rate was zero; the complication rate was 69%. Patients in whom the Kocher maneuver was not performed (group 2) experienced fewer complications, shorter stay on nasogastric tube and abdominal drain(s), and earlier water intake and discharge. Type of DPPHR did not influence the postoperative course. One patient died 3 months after surgery of unrelated disease. Twelve patients were alive and well 2 months to 8 years after surgery.

CONCLUSION

DPPHR is a low-risk procedure in patients with benign or borderline noninflammatory lesions of the head of the pancreas in whom pylorus-preserving pancreaticoduodenectomy is otherwise indicated. Whenever possible, the Kocher maneuver should be avoided.