A prospective diagnostic accuracy study of 18F-fluorodeoxyglucose positron emission tomography/computed tomography, multidetector row computed tomography, and magnetic resonance imaging in primary diagnosis and staging of pancreatic cancer. Ann Surg. 2009;250:957-963. [PMID: 19687736 DOI: 10.1097/sla.0b013e3181b2fafa]

Utility of PET/CT in diagnosis, staging, assessment of resectability and metabolic response of pancreatic cancer

Pancreatic cancer is one of the most common gastrointestinal tumors, with its incidence staying at a high level in both the United States and China. However, the overall 5-year survival rate of pancreatic cancer is still extremely low. Surgery remains the only potential chance for long-term survival. Early diagnosis and precise staging are crucial to make proper clinical decision for surgery candidates. Despite advances in diagnostic technology such as computed tomography (CT) and endoscopic ultrasound, diagnosis, staging and monitoring of the metabolic response remain a challenge for this devastating disease. Positron emission tomography/CT (PET/CT), a relatively novel modality, combines metabolic detection with anatomic information. It has been widely used in oncology and achieves good results in breast cancer, lung cancer and lymphoma. Its utilization in pancreatic cancer has also been widely accepted. However, the value of PET/CT in pancreatic disease is still controversial. Will PET/CT change the treatment strategy for potential surgery candidates? What kind of patients benefits most from this exam? In this review, we focus on the utility of PET/CT in diagnosis, staging, and assessment of resectability of pancreatic cancer. In addition, its ability to monitor metabolic response and recurrence after treatment will be emphasis of discussion. We hope to provide answers to the questions above, which clinicians care most about.

Prognostic significance of volume-based FDG PET/CT parameters in patients with locally advanced pancreatic cancer treated with chemoradiation therapy

PURPOSE

We investigated the prognostic role of volume-based parameters measured on 18F-fluorodeoxyglucose (FDG) positron emission tomography-computed tomography (PET/CT) scans in patients with locally advanced pancreatic cancer (LAPC) treated with chemoradiation therapy (CRT).

MATERIALS AND METHODS

We enrolled 60 patients with LAPC who underwent FDG PET/CT before CRT. Maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) of primary pancreatic cancers were measured on FDG PET/CT scans. Treatment response was evaluated according to the Response Evaluation Criteria in Solid Tumors. Survival analysis was performed using the Kaplan-Meier method, and Cox proportional hazard models were used to determine independent prognostic factors.

RESULTS

The progression-free survival (PFS), locoregional progression-free survival (LRFPS), and overall survival (OS) for this population were 6.2, 10.9, and 13.2 months, respectively. The overall treatment response rate was 16.7% at 4 weeks after CRT, and the disease control rate (DCR) was 80.0%. DCR was significantly higher in patients with low SUVmax, MTV, or TLG, and showed strong correlation with longer survival times. On univariate analysis, MTV and TLG were significant prognostic factors for PFS, LRPFS, and OS, together with pre-CRT and post-CRT CA19-9 levels. Multivariate analyses demonstrated that MTV together with the pre-CRT CA19-9 level were independent prognostic factors for PFS, LRPFS, and OS, as was TLG for LRPFS and OS.

CONCLUSION

MTV and the pre-CRT CA19-9 level provided independent prognostic information in patients with LAPC treated with CRT. Volume-based PET/CT parameters may be useful in identifying which subgroup of patients would benefit from radiation therapy as a part of CRT.

[18F]Fluorodeoxyglucose PET/Computed Tomography in Gastrointestinal Malignancies

This article discusses the current state-of-the-art application of 2-deoxy-2-[(18)F]fluoro-d-glucose (FDG)-PET and FDG-PET/computed tomography (CT) in the management of patients with gastrointestinal malignancies. Gastrointestinal malignancies include many different cell types, several common malignancies of which may be imaged by FDG-PET/CT. This review focuses on gastric carcinoma, pancreatic carcinoma, hepatocellular carcinoma, cholangiocarcinoma, colorectal carcinoma, and stroma cell tumors. The role of FDG-PET/CT in staging these malignancies is discussed, in addition to (re)staging, detection of recurrent disease, patient selection/prognostication, and response assessment, using the currently available literature.

The role of (18)fluoro-deoxyglucose positron emission tomography/computed tomography in resectable pancreatic cancer

BACKGROUND

The role of (18)fluoro-deoxyglucose positron emission tomography/computed tomography in pancreatic ductal adenocarcinoma is debated. We retrospectively assessed the value of (18)fluoro-deoxyglucose positron emission tomography/computed tomography in addition to conventional imaging as a staging modality in pancreatic cancer.

METHODS

(18)Fluoro-deoxyglucose positron emission tomography/computed tomography was performed in 72 patients with resectable pancreatic carcinoma after multi-detector computed tomography positron emission tomography was considered positive for a maximum standardized uptake value >3.

RESULTS

Overall, 21% of patients had a maximum standardized uptake value ≤ 3, and 60% of those had undergone neoadjuvant treatment (P=0.0001). Furthermore, 11% of patients were spared unwarranted surgery since positron emission tomography/computed tomography detected metastatic disease. All liver metastases were subsequently identified with contrast-enhanced ultrasound. Sensitivity and specificity of positron emission tomography/computed tomography for distant metastases were 78% and 100%. The median CA19.9 concentration was 48.8 U/mL for the entire cohort and 292 U/mL for metastatic patients (P=0.112).

CONCLUSIONS

The widespread application of (18)fluoro-deoxyglucose positron emission tomography/computed tomography in patients with resectable pancreatic carcinoma seems not justified. It should be considered in selected patients at higher risk of metastatic disease (i.e. CA19.9>200 U/mL) after undergoing other imaging tests. Neoadjuvant treatment is significantly associated with low metabolic activity, limiting the value of positron emission tomography in this setting.

Cell-free DNA for the detection of pancreatic, liver and upper gastrointestinal cancers: has progress been made?

Detecting alterations in blood cell-free DNA (cfDNA) is hoped to be a novel, noninvasive method for diagnosing, prognosing and monitoring cancer patients. Several studies have assessed the usefulness of measuring tumor-specific genetic and epigenetic changes of cfDNA, such as loss of heterozygosity, frequency of mutations, alterations of microsatellites and the methylation of genes in patient blood samples. However, few well-designed trials have been carried out to translate these findings effectively. In this review, we have assessed the clinical utility of cfDNA in pancreatic, liver and upper gastrointestinal malignancies.

Imaging diagnosis of pancreatic cancer: A state-of-the-art review

Pancreatic cancer (PC) remains one of the deadliest cancers worldwide, and has a poor, five-year survival rate of 5%. Although complete surgical resection is the only curative therapy for pancreatic cancer, less than 20% of newly-diagnosed patients undergo surgical resection with a curative intent. Due to the lack of early symptoms and the tendency of pancreatic adenocarcinoma to invade adjacent structures or to metastasize at an early stage, many patients with pancreatic cancer already have advanced disease at the time of their diagnosis and, therefore, there is a high mortality rate. To improve the patient survival rate, early detection of PC is critical. The diagnosis of PC relies on computed tomography (CT) and/or magnetic resonance imaging (MRI) with magnetic resonance cholangiopancreatography (MRCP), or biopsy or fine-needle aspiration using endoscopic ultrasound (EUS). Although multi-detector row computed tomography currently has a major role in the evaluation of PC, MRI with MRCP facilitates better detection of tumors at an early stage by allowing a comprehensive analysis of the morphological changes of the pancreas parenchyma and pancreatic duct. The diagnosis could be improved using positron emission tomography techniques in special conditions in which CT and EUS are not completely diagnostic. It is essential for clinicians to understand the advantages and disadvantages of the various pancreatic imaging modalities in order to be able to make optimal treatment and management decisions. Our study investigates the current role and innovative techniques of pancreatic imaging focused on the detection of pancreatic cancer.

Prognostic Value of Metabolic Tumor Volume and Total Lesion Glycolysis on Preoperative ¹⁸F-FDG PET/CT in Patients with Pancreatic Cancer

In this study, we aimed to assess the prognostic value of metabolic tumor volume (MTV) and total lesion glycolysis (TLG) measured on (18)F-FDG PET/CT in pancreatic cancer patients who underwent resection with curative intent.

METHODS

Eighty-seven patients with pancreatic ductal adenocarcinoma who underwent (18)F-FDG PET/CT and subsequent surgical resection with curative intent with (30 patients) or without (57 patients) neoadjuvant therapy were retrospectively enrolled. The maximum standardized uptake value (SUVmax), MTV, and TLG were measured on (18)F-FDG PET/CT in all patients. The prognostic significances of PET/CT parameters and tumor factors for recurrence-free survival (RFS) and overall survival (OS) were evaluated by univariate and multivariate analyses.

RESULTS

Of the 87 patients, 57 (64%) experienced recurrence during the follow-up period. The tumor size, pathologic T (pT) stage, SUVmax, MTV, and TLG were significant prognostic factors for both RFS and OS (P < 0.05) on univariate analyses, and the presence of lymph node metastasis showed significance only for predicting RFS (P < 0.05). On multivariate analyses, the tumor size, MTV, and TLG were independent prognostic factors for RFS, and pT stage, MTV, and TLG were independent prognostic factors for OS. For the 57 patients who did not undergo neoadjuvant treatment, MTV and TLG remained significant predictive factors for tumor recurrence, along with tumor size and SUVmax.

CONCLUSION

MTV and TLG are independent prognostic factors for predicting RFS and OS in patients with pancreatic cancer. Thus, (18)F-FDG PET/CT can provide useful prognostic information for patients undergoing resection of pancreatic cancer with curative intent irrespective of neoadjuvant treatment.

Usefulness of F-18-fluorodeoxyglucose positron emission tomography to confirm suspected pancreatic cancer: a meta-analysis

INTRODUCTION

Pancreatic cancer is among the five most lethal malignancies in the world. Unfortunately, many malignant tumors go undetected by the current primary diagnostic tools. (18)FDG-PET and (18)FDG-PET/CT might be useful to confirm suspected pancreatic cancer.

METHODS

A meta-analysis was performed using all major search engines. Methodological quality of included studies was assessed as well as quality of the PET-protocol. The following pooled estimates served as primary outcome measures: sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy.

RESULTS

Thirty-five studies were included. Pooled estimates for (18)FDG-PET were: sensitivity 90%, specificity 76%, PPV 90%, NPV 76% and accuracy 86%. Pooled estimates for (18)FDG-PET/CT were: sensitivity 90%, specificity 76%, PPV 89%, NPV 78% and accuracy 86%. The pooled sensitivity and specificity for (18)FDG-PET to differentiate between pancreatic cancer and chronic pancreatitis were 90% and 84%, respectively.

CONCLUSION

Both (18)FDG-PET and (18)FDG-PET/CT offer no benefit over the current primary diagnostic tools in diagnosing pancreatic cancer. However, the (18)FDG-PET/CT systems are still improving. We should investigate the sensitivity and specificity of these new systems while reevaluating the tradeoff between false positive and false negative results. Yet, (18)FDG-PET/CT may have a role in the staging of pancreatic cancer, in survival prediction, and may add to other diagnostic information, like histology.

Pancreatic solitary and synchronous metastasis from breast cancer: a case report and systematic review of controversies in diagnosis and treatment

Background

Metastases from breast cancer cause the frequent involvement of lung, bone, liver, and brain, while the occurrence of metastases to the gastrointestinal tract is rare, and more frequently discovered after a primary diagnosis of breast cancer. Solitary pancreatic metastases from breast cancer, without widespread disease, are actually unusual, and only 19 cases have been previously described; truly exceptional is a solitary pancreatic metastasis becoming evident together with the primary breast cancer.

Case presentation

A 68-year-old woman reported general fatigue, lethargy, and jaundice. Abdominal ultrasound (US) and magnetic resonance imaging (MRI) showed an ampulloma of Vater’s papilla; moreover, a neoplastic nodule in the left breast was diagnosed. She underwent surgery for both breast cancer and ampulloma of Vater’s papilla. Pathological examination of pancreatic specimen, however, did not confirm primary carcinoma of the duodenal papilla, but showed a metastatic involvement of pancreas from lobular breast cancer. Immunohistochemistry has been essential to confirm the origin of the malignancy: hormone receptors and mammaglobin were expressed in both the primary breast tumor and the pancreatic metastasis.

Conclusions

This is one of the few reported cases in literature of an isolated and synchronous pancreatic metastasis from breast cancer, where the definitive diagnosis was obtained only after surgery. We discuss the controversies in this diagnosis and the choice of correct treatment. The surgical resection of solitary metastases can be performed in the absence of disseminated disease.

Staging chest computed tomography and positron emission tomography in patients with pancreatic adenocarcinoma: utility or futility?

OBJECTIVES

This study was conducted to determine if routine staging chest computed tomography (CT) or positron emission tomography (PET) scanning alters the clinical management of patients with newly diagnosed pancreatic adenocarcinoma.

METHODS

All new pancreas cancers seen in medical oncology, radiation oncology and surgery from 1 June 2008 to 20 June 2010 were retrospectively reviewed. Patients with metastatic disease on chest CT or PET, that had been unsuspected on initial imaging, were identified.

RESULTS

Pancreatic adenocarcinoma was present in 247 consecutive patients. Abdominal CT demonstrated metastases in 108 (44%) and localized disease in 139 (56%) patients. Chest CT and PET were not performed in 15 (11%) of these 139 patients. In the remaining 124 patients, CT imaging suggested resectable disease in 46, borderline resectable disease in 52 and locally advanced disease in 26 patients. Chest CT demonstrated an unsuspected lymphoma in one patient with borderline resectable disease and PET identified extrapancreatic disease in two patients with locally advanced disease. Chest CT and PET added no information in 121 (98%) of the 124 patients.

CONCLUSIONS

The addition of chest CT and PET to high-quality abdominal CT is of little clinical utility; additional sites of metastasis are rarely found. As the quality of abdominal imaging declines, the yield from other imaging modalities will increase. Dedicated pancreas-specific abdominal CT remains the cornerstone of initial staging in suspected or biopsy-proven pancreatic cancer.

Accurate prediction of nodal status in preoperative patients with pancreatic ductal adenocarcinoma using next-gen nanoparticle

OBJECTIVE

The objective of this study is to assess lymphotropic nanoparticle-enhanced magnetic resonance imaging (LNMRI) in identifying malignant nodal involvement in patients with pancreatic ductal adenocarcinoma.

METHODS

Magnetic resonance imaging was performed in 13 patients with known or high index of suspicion of pancreatic cancer and who were scheduled for surgical resection. Protocols included T2*-weighted imaging before and after administration of Ferumoxytol (Feraheme) for the evaluation of lymph node involvement. Eleven of the 13 patients underwent a Whipple procedure and lymph node dissection. Nodes that lacked contrast uptake were deemed malignant, and those that demonstrated homogeneous uptake were deemed benign.

RESULTS

A total of 264 lymph nodes were resection, of which 17 were malignant. The sensitivity and specificity of LNMRI was 76.5% and 98.4% at a nodal level and 83.3% and 80% at a patient level.

CONCLUSION

LNMRI demonstrated high sensitivity and specificity in patients with pancreatic ductal adenocarcinoma.

The role of 18F-fluorodeoxyglucose positron emission tomography in the management of patients with pancreatic adenocarcinoma

Pancreatic cancer continues to have a grim prognosis with 5-year survival rates at less than 5 %. It is a particularly challenging health problem given these poor survival outcomes, aggressive tumor biology, and late onset of symptoms. Most patients present with advanced unresectable cancer however, margin-negative resection provides a rare chance for cure for patients with resectable disease. The standard imaging modality for the diagnosis and management of pancreatic cancer is contrast-enhanced multidetector computed tomography. Remarkable advances in CT technology have led to improvements in the ability to detect small tumors and intricate vasculature involvement by the tumor, yet CT is still restricted to providing a morphological portrait of the tumor. Diagnosis can be challenging due to similar appearance of certain benign and malignant disease. Distant metastatic disease can be silent on CT leading to improper staging, and thus management, of certain patients. Furthermore, radiation-induced fibrosis and necrosis complicate assessment of treatment response by CT alone. F-fluorodeoxyglucose positron emission tomography (18F-FDG-PET) is becoming a prevalent tool employed by physicians to improve accuracy in these clinical scenarios. Malignant transformation causes a high metabolic activity of cancer cells. 18F-FDG-PET captures this functional activity of malignancies by capturing areas with high glucose utilization rates. Imaging function rather than morphological appearance, 18F-FDG-PET has a unique role in the management of oncology patients with the ability to detect regions of tumor involvement that may be silent on conventional imaging. Literature on the sensitivity and specificity of 18F-FDG-PET fails to reach a consensus, and improvements resulting in hybridization of 18F-FDG-PET and CT imaging techniques are preliminary. Here we review the potential role of 18F-FDG-PET and PET/CT in improving accuracy in the initial evaluation and subsequent steps in the management of pancreatic cancer patients.

Limited efficacy of (18)F-FDG PET/CT for differentiation between metastasis-free pancreatic cancer and mass-forming pancreatitis

OBJECTIVE

Differentiation between metastasis-free pancreatic cancer and mass-forming pancreatitis is important to avoid unnecessary operative procedures. This study was aimed at evaluating the efficacy of PET/CT with F-FDG (FDG PET/CT) for the differential diagnosis between them.

PATIENTS AND METHODS

FDG-PET/CT was performed in 47 study patients with pancreatic masses and without any detectable metastases, 33 of which cases were finally diagnosed as pancreatic cancer and the other 14 as pancreatitis, and the corresponding imaging data were evaluated retrospectively. The maximal SUV (SUVmax) within the masses were determined at 1 hour and mostly at 2 hours after intravenous injection of FDG.

RESULTS

SUVmax at 1 hour in pancreatic cancer was significantly higher than that in mass-forming pancreatitis, and the change in SUVmax from 1- to 2-hour time points was more consistent with pancreatic cancer than with mass-forming pancreatitis. However, there remained considerable overlapping between the SUVmax values of both diseases except either at the higher range for pancreatic cancer (> 7.7 at 1 hour or > 9.98 at 2 hours) or at the lower range for mass-forming pancreatitis (<3.37 at 1 hour or <3.53 at 2 hours). No obvious difference was found in the FDG uptake patterns of the mass areas between both diseases.

CONCLUSIONS

Differentiation between metastasis-free pancreatic cancer and mass-forming pancreatitis is difficult by FDG-PET/CT due to considerable overlapping between the SUVmax values of the two diseases, although the differential diagnosis may be possible either at the higher range of SUVmax (> 7.7 at 1 hour or > 9.98 at 2 hours) for pancreatic cancer or at the lower range of SUVmax (<3.37 at 1 hour or <3.53 at 2 hours) for mass-forming pancreatitis.

Prognostic value of 18F-fluorodeoxyglucose positron emission tomography in patients with resectable pancreatic cancer

PURPOSE

We evaluated the prognostic value of (18)F-2-fluoro-2-deoxyglucose positron emission tomography (FDG PET) in patients with resectable pancreatic cancer.

MATERIALS AND METHODS

We retrospectively reviewed the medical records of pancreatic cancer patients who underwent curative resection, which included 64 consecutive patients who had preoperative FDG PET scans. For statistical analysis, the maximal standardized uptake value (SUVmax) of primary pancreatic cancer was measured. Survival time was estimated by the Kaplan-Meier method, and Cox's proportional hazard model was used to determine whether SUVmax added new predictive information concerning survival together with known prognostic factors. p<0.05 indicated statistical significance.

RESULTS

Overall survival (OS) and disease- free survival (DFS) were respectively 42.9 months (27.6-58.2; 95% CI) and 14.9 months (10.1-19.7; 95% CI). When subjects were divided into two groups according to SUVmax with a cutoff value of 3.5, the high SUVmax group (n=32; SUVmax >3.5) showed significantly shorter OS and DFS than the low SUVmax group. Multivariate analysis of OS and DFS showed that both high SUVmax and poor tumor differentiation were independent poor prognostic factors.

CONCLUSION

Our study showed that degree of FDG uptake was an independent prognostic factor in pancreatic cancer patients who underwent curative resection.

Diagnostic and prognostic value of circulating tumor-related DNA in cancer patients

Qualitative and quantitative analysis of circulating cell-free DNA (cfDNA) is an emerging non-invasive blood biomarker utilized to assess tumor progression and to evaluate prognosis, diagnosis and response to treatment. There is a need to develop cfDNA biomarkers to avoid complex risk-prone biopsy procedures for primary or metastatic tumors. Given the challenges associated with inter- and intra-tumor heterogeneity, the implementation of genome-wide cfDNA analysis will become an important avenue to understand tumor progression and therapeutic settings, not only for predominant, but also for under-represented tumor subclones with specific genomic aberrations. We summarize the latest publications in cfDNA analysis, including a metric analysis of clinical trials and new high-throughput technology applied to cfDNA analysis in clinical oncology.

Role of (18)F-fluorodeoxyglucose positron emission tomography/computed tomography in diagnosis and management of pancreatic cancer; comparison with multidetector row computed tomography, magnetic resonance imaging and endoscopic ultrasonography

OBJECTIVES

We aimed to analyze the contribution of (18)F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) imaging to the diagnosis and management of pancreatic cancer compared with multidetector row computed tomography (MDCT), magnetic resonance imaging (MRI) and endoscopic ultrasonography (EUS).

MATERIAL AND METHODS

We retrospectively scanned the data of 52 patients who were referred for FDG PET/CT imaging for evaluation of pancreatic lesions greater than 10mm. The diagnostic performances of 4 imaging methods and the impact of PET/CT on the management of pancreatic cancer were defined.

RESULTS

Pancreatic adenocarcinoma was diagnosed in 33 of 52 patients (63%), 15 patients had benign diseases of pancreas (29%), and 4 patients were normal (8%). Sensitivity and NPV of EUS and PET/CT were equal (100%) and higher than MDCT and MRI. Specificity, PPV and NPV of PET/CT were significantly higher than MDCT. However, sensitivities of two imaging methods were not significantly different. There was no significant difference between PET/CT and MRI and EUS for these values. When the cut-off value of SUVmax was 3.2, the most effective sensitivity and specificity values were obtained. PET/CT contributed to the management of pancreatic cancer in 30% of patients.

CONCLUSION

FDG PET/CT is a valuable imaging method for the diagnosis and management of pancreatic cancer, especially when applied along with EUS as first line diagnostic tools.

Applying PET to broaden the diagnostic utility of the clinically validated CA19.9 serum biomarker for oncology

Despite their considerable advantages, many circulating biomarkers have well-documented limitations. One prominent shortcoming in oncology is a high frequency of false-positive indications for malignant disease in upfront diagnosis. Because one common cause of false positivism is biomarker production from benign disorders in unrelated host tissues, we hypothesized that probing the sites of biomarker secretion with an imaging tool could be a broadly useful strategy to deconvolute the meaning of foreboding but inconclusive circulating biomarker levels.

METHODS

In preparation to address this hypothesis clinically, we developed (89)Zr-5B1, a fully human, antibody-based radiotracer targeting tumor-associated CA19.9 in the preclinical setting.

RESULTS

(89)Zr-5B1 localized to multiple tumor models representing diseases with undetectable and supraphysiologic serum CA19.9 levels. Among these, (89)Zr-5B1 detected orthotopic models of pancreatic ductal adenocarcinoma, an elusive cancer for which the serum assay is measured in humans but with limited specificity in part because of the frequency of CA19.9 secretion from benign hepatic pathologies.

CONCLUSION

In this report, a general strategy to supplement some of the shortcomings of otherwise highly useful circulating biomarkers with immunoPET is described. To expedite the clinical validation of this model, a human monoclonal antibody to CA19.9 (a highly visible but partially flawed serum biomarker for several cancers) was radiolabeled and evaluated, and the compelling preclinical evidence suggests that the radiotracer may enhance the fidelity of diagnosis and staging of pancreatic ductal adenocarcinoma, a notoriously occult cancer.

Role of positron emission tomography-computed tomography in gastrointestinal malignancies

Positron emission tomography (PET) has proved itself to be valuable in the evaluation of patients with a wide array of gastrointestinal (GI) malignancies. Subsequent development of fusion imaging with PET and computed tomography (PET-CT) scanners has significantly advanced the capabilities of imaging by combining the functional data of the(18)F-labeled glucose analogue fluorodeoxyglucose (FDG) with the conventional anatomic data provided by CT. This article reviews the evolving role of FDG PET-CT imaging in the initial assessment and monitoring of GI tumors. Specific applications are discussed, and normal variants and benign findings frequently encountered during PET-CT of the GI tract are reviewed.

Pancreatic cystic neoplasms: a review of preoperative diagnosis and management

Pancreatic cystic neoplasms (PCNs) are a diverse group of neoplasms in the pancreas, and are more increasingly encountered with widespread abdominal screening and improved imaging techniques. The most common types of PCNs are serous cystic neoplasms (SCNs), mucinous cystic neoplasms (MCNs), and intraductal papillary mucinous neoplasms (IPMNs). Clinicians frequently feel bewildered in the differential diagnosis and subsequent management among the various types of lesions in the pancreas, which may lead to overtreatment or delayed treatment. The current review provides recent developments in the understanding of the three most common types of PCNs, the latest modalities used in preoperative diagnosis and differential diagnosis, as well as the most up to date management. Suggestions for diagnosis and differential diagnosis of SCNs, MCNs, and IPMNs are also provided for young surgeons. Better understanding of these neoplasms is essential for clinicians to make accurate diagnosis and to provide the best management for patients.

Multimodality imaging of pancreatic cancer-computed tomography, magnetic resonance imaging, and positron emission tomography

Pancreatic adenocarcinoma continues to have a dismal prognosis, with curative surgery (resection with negative margins) possible in only a small percentage of patients. Not only does radiological imaging play a major role in diagnosing the primary lesion at presentation, but it is also crucial for staging of locoregional disease and distant metastases, both of which are critical for selecting appropriate candidates for surgery. Over the last 2 decades, computed tomography has become the dominant imaging modality for both the diagnosis and staging of pancreatic cancer, with advances in multidetector computed tomography technology improving the ability to identify small tumors and demonstrate subtle degrees of vascular involvement by tumor. However, magnetic resonance imaging and positron emission tomography are now playing an increasing role in pancreatic cancer imaging. These 3 imaging modalities each have specific strengths and benefits and should be used in a complementary fashion.

FDG-PET in diagnosis, staging and prognosis of pancreatic carcinoma: a meta-analysis

AIM

To investigate the potential role of positron emission tomography (PET) in the diagnosis, staging and prognosis predicting of pancreatic carcinoma (PC).

METHODS

A systematic review of relevant literatures in PubMed, Embase and Cochrane Library was performed. The sensitivity and specificity of diagnostic and staging studies, and HRs for prognosis predicting studies were pooled. The bivariate model was used for diagnostic studies and the random-effect model for prognostic studies. Heterogeneity between included studies was tested using χ(2) test, and subgroup analysis was performed to explain the heterogeneities. All of the calculations were performed using Stata version 11.0.

RESULTS

A total of 39 studies were included. The pooled sensitivity of PET in diagnosing PC (30 studies, 1582 patients), evaluating N stating (4 studies, 101 patients) and liver metastasis (7 studies, 316 patients) were 0.91 (95%CI: 0.88-0.93), 0.64 (95%CI: 0.50-0.76), and 0.67 (95%CI: 0.52-0.79), respectively; and the corresponding specificity was 0.81 (95%CI: 0.75-0.85), 0.81 (95%CI: 0.25-0.85), and 0.96 (95%CI: 0.89-0.98), respectively. In prognosis analysis (6 studies, 198 patients), significant difference of overall survival was observed between high and low standardized uptake value groups (HR = 2.39, 95%CI: 1.57-3.63). Subgroup analysis showed that PET/CT was more sensitive than PET alone in evaluating liver metastasis of PC, 0.82 (95%CI: 0.48-0.98) and 0.67 (95%CI: 0.52-0.79), respectively.

CONCLUSION

PET can be used as a valuable diagnostic and predictive tool for PC, but its effect in the staging of PC remains indeterminate.

18-Fluorodeoxyglucose positron emission tomography does not aid in diagnosis of pancreatic ductal adenocarcinoma

BACKGROUND & AIMS

There are no accurate and reliable tools for diagnosis of early stage pancreatic ductal adenocarcinoma (PDA) or small metastatic lesions. It is also a challenge to differentiate PDA from focal mass-forming pancreatitis (FMP). There is controversy regarding the efficacy of 18-fluorodeoxyglucose positron-emission tomography (FDG-PET) in the diagnosis of PDA. We investigated whether FDG-PET provides information that, combined with data from other imaging techniques, can aid in decision making for patients with suspected PDA.

METHODS

We performed a retrospective analysis of data collected from 232 consecutive patients with suspected PDA at Kobe University Hospital from January 2006 through June 2012. All patients underwent a diagnostic imaging protocol that included multidetector row computed tomography, superparamagnetic iron oxide-enhanced magnetic resonance imaging, and FDG-PET. Based on endoscopic ultrasonography, fine-needle aspiration biopsy, or endoscopic retrograde cholangiopancreatography analyses, 218 patients had PDA (89 underwent resection and 129 did not) and 14 patients had FMP (8 had focal mass-forming chronic pancreatitis and 6 had focal mass-forming autoimmune pancreatitis).

RESULTS

FDG-PET detected 50% of stages 0 and I, 91.9% of stage II, 100% of stage III, and 96.8% of stage IV tumors. Detection was affected significantly by tumor size (P = .024) and T stage (P = .023) in resected tumors. Multidetector row computed tomography detected significantly more liver metastases than FDG-PET. Few para-aortic lymph node or peritoneal metastases were detected by FDG-PET. FDG-PET correctly identified 11 of the 14 patients with FMP (5 of 8 with focal mass-forming chronic pancreatitis and 6 of 6 with focal mass-forming autoimmune pancreatitis).

CONCLUSIONS

FDG-PET is not effective in detecting early stage PDA and small metastases, or in differentiating PDA from FMP. Combining FDG-PET with current diagnostic techniques for PDA did not provide any decisive information, therefore it should not be included in this analysis.

Diagnosis and management of cystic pancreatic lesions

OBJECTIVE

The purpose of this review is to outline the management guidelines for the care of patients with cystic pancreatic lesions.

CONCLUSION

The guidelines are as follows: Annual imaging surveillance is generally sufficient for benign serous cystadenomas smaller than 4 cm and for asymptomatic lesions. Asymptomatic thin-walled unilocular cystic lesions smaller than 3 cm or side-branch intraductal papillary mucinous neoplasms should be followed up with CT or MRI at 6 and 12 months interval after detection. Cystic lesions with more complex features or with growth rates greater than 1 cm/year should be followed more closely or recommended for resection if the patient's condition allows surgery. Symptomatic cystic lesions, neoplasms with high malignant potential, and lesions larger than 3 cm should be referred for surgical evaluation. Endoscopic ultrasound with fine-needle aspiration (FNA) biopsy can be used preoperatively to assess the risk of malignancy.

Positron emission tomography in malignancies of the liver, pancreas and biliary tract - indications and potential pitfalls

Abstract Malignancies of the hepato-pancreatico-biliary (HPB) system are relatively common and generally characterized by a dismal prognosis. Positron emission tomography (PET) is a functional imaging technique that has emerged as an important modality in oncological decision-making. The principal radiopharmaceutical in PET imaging is the glucose analog (18)F-fluorodeoxyglucose, which is able to detect altered glucose metabolism in malignant tissue. PET is typically used in conjunction with computed tomography (CT), and previous studies have supported several uses of PET/CT in HPB malignancies, including staging, differential diagnostics and monitoring of treatment response and progress of disease. A review of PET/CT in the context of HPB malignancies will be presented, including indications and potential pitfalls.

Role of (18)F-fluorodeoxyglucose positron emission tomography/computed tomography in the characterization of pancreatic masses: experience from tropics

BACKGROUND AND AIM

Early detection and differentiation of malignant from benign pancreatic tumors is very essential as mass-forming pancreatitis is a frequently encountered problem. Positron emission tomography (PET) has a role in establishing the diagnosis of pancreatic carcinoma when the conventional imaging modalities or biopsies are nondiagnostic. In this prospective study, the utility of fluorodeoxyglucose (FDG)-PET/computed tomography (CT) in the characterization of mass-forming lesions of the pancreas was reported.

METHODS

(18)F-FDG-PET/CT was prospectively performed in 87 patients diagnosed to have periampullary or pancreatic mass. Lesions with focally increased FDG uptake in PET/CT were considered malignant, whereas those with diffuse or no FDG uptake were considered benign. Semiquantitative analysis with maximum standardized uptake value (SUVmax) was also calculated. The PET/CT results were compared with histopathological results in all patients.

RESULTS

Based on the FDG uptake pattern, sensitivity, specificity, positive predictive value, negative predictive value, and accuracy for FDG-PET/CT in characterizing the periampullary and pancreatic masses into benign and malignant lesions were 93%, 90%, 95%, 87%, and 92% respectively. Receiver operating characteristics curve analysis of the SUVmax of the lesions yielded a cut-off value of 2.8, with a sensitivity and specificity of 87.5% and 45% respectively.

CONCLUSION

The FDG uptake pattern in PET/CT can differentiate malignant from benign mass-forming lesions of the pancreas with high accuracy and a discrete cut-off value of SUVmax could not be defined for the same as even lesions with pancreatic tuberculosis showed very high FDG uptake. Hence, in patients with a suspicion of malignancy in the pancreas, a focally increase FDG uptake in PET/CT suggests the diagnosis of malignancy.

PET/CT of cancer patients: part 1, pancreatic neoplasms

OBJECTIVE

Pancreatic cancer continues to have a poor prognosis despite impressive improvements in the outcomes of many other types of cancer, often because most pancreatic neoplasms are found to be unresectable at diagnosis. The purpose of this review is to provide an overview of pancreatic cancer and the role of modern imaging in its diagnosis and management with an emphasis on (18)F-FDG PET/CT fusion imaging.

CONCLUSION

Multimodality imaging is critical in the diagnosis and management of pancreatic cancer. PET/CT is increasingly viewed as a useful, accurate, and cost-effective modality in diagnosing and managing pancreatic cancer, but further studies are warranted. Early data suggest that contrast-enhanced PET/CT performed with modern PET/CT scanners yields high-resolution anatomic information for surgical and radiotherapeutic planning and functional information for whole-body staging in the care of patients with this disease.

State-of-the-art PET/CT of the pancreas: current role and emerging indications

Fused positron emission tomography (PET)/computed tomography (CT) is a recently developed technology that couples the functional information of PET with the anatomic details of CT. Integrated PET/CT scanners produce both PET and contrast material-enhanced CT images of the entire body in one setting. Typically, the amount of fluorine 18 (18F) fluorodeoxyglucose (FDG) uptake in normal pancreatic parenchyma is insignificant compared with that of the liver. However, both malignant (eg, adenocarcinoma) and benign (eg, acute pancreatitis) pancreatic conditions may demonstrate intense FDG uptake. PET/CT provides an opportunity to depict pancreatic tumors and distant metastases, perform preoperative staging, and monitor response to treatment, and it has proved useful in distinguishing postoperative fibrosis from recurrence. In selected cases, PET/CT findings may be used to help diagnose autoimmune pancreatitis mimicking a mass by depicting systemic involvement. PET/CT may also be used to direct biopsy to sites more likely to yield representative tumor tissue. Novel radiolabeled molecules, such as sigma-receptor ligands and 18F-3'-fluoro-3'-deoxy-l-thymidine (FLT), may play an even greater role in distinguishing tumor recurrence from postoperative fibrosis or inflammation.

Sister Mary Joseph’s nodule as a first sign of pancreatic cancer

Sister Mary Joseph’s nodule (SMJN) refers to a metastatic tumor of the umbilicus. It is a rare entity which arises from a malignancy in the intra-abdominal cavity. We herein describe a patient who presented with SMJN as his first sign of pancreatic cancer. It is an even more unusual case of SMJN. We therefore, suggest that pancreatic cancer should be included in the differential diagnosis when an umbilical mass is found. With the progress made in surgical procedures and other modalities, an early diagnosis will dramatically improve the prognosis of the patients.

Pancreatic Adenocarcinoma, version 2.2012: featured updates to the NCCN Guidelines

The NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Pancreatic Adenocarcinoma discuss the workup and management of tumors of the exocrine pancreas. These NCCN Guidelines Insights provide a summary and explanation of major changes to the 2012 NCCN Guidelines for Pancreatic Adenocarcinoma. The panel made 3 significant updates to the guidelines: 1) more detail was added regarding multiphase CT techniques for diagnosis and staging of pancreatic cancer, and pancreas protocol MRI was added as an emerging alternative to CT; 2) the use of a fluoropyrimidine plus oxaliplatin (e.g., 5-FU/leucovorin/oxaliplatin or capecitabine/oxaliplatin) was added as an acceptable chemotherapy combination for patients with advanced or metastatic disease and good performance status as a category 2B recommendation; and 3) the panel developed new recommendations concerning surgical technique and pathologic analysis and reporting.

Performance of whole-body PET/CT for the detection of distant malignancies in various cancers: a systematic review and meta-analysis

At present, there is no ideal imaging modality for the diagnosis of distant metastases and second primary cancers in cancer patients. We aimed to assess the accuracy of whole-body PET/CT for the overall assessment of distant malignancies in patients with various cancers.

METHODS

Studies about whole-body PET/CT for the detection of distant malignancies in cancer patients were systematically searched in MEDLINE and EMBASE. We determined sensitivities and specificities across studies, calculated positive and negative likelihood ratios, and constructed summary receiver operating characteristic curves using hierarchical regression models for whole-body PET/CT.

RESULTS

Across 41 studies (4,305 patients), the sensitivity and specificity of whole-body PET/CT were 0.93 (95% confidence interval [CI], 0.88-0.96) and 0.96 (95% CI, 0.95-0.96), respectively. Subgroup analysis showed that the sensitivity and specificity of whole-body PET/CT for various cancers, respectively, were as follows: head and neck cancer, 0.90 (95% CI, 0.83-0.95) and 0.95 (95% CI, 0.94-0.96); lung cancer, 0.91 (95% CI, 0.76-0.97) and 0.96 (95% CI, 0.94-0.98); breast cancer, 0.97 (95% CI, 0.93-0.99) and 0.95 (95% CI, 0.90-0.97); and cancer of digestive system, 0.92 (95% CI, 0.68-0.98) and 0.97 (95% CI, 0.91-0.99).

CONCLUSION

Whole-body PET/CT has excellent diagnostic performance for the overall assessment of distant malignancies in patients with various cancers, especially head and neck cancer, breast cancer, and lung cancer.

Role of respiratory-gated PET/CT for pancreatic tumors: a preliminary result

PURPOSE

The aim of this study is to ascertain role of respiratory-gated PET/CT for accurate diagnosis of pancreatic tumors.

MATERIALS AND METHODS

Prior to clinical study, the phantom study was performed to evaluate the impact of respiratory motion on lesion quantification. Twenty-two patients (mean age 65 years) with pancreatic tumors were enrolled. Pathological diagnoses by surgical specimens consisted of pancreatic cancer (n=15) and benign intraductal papillary mucinous neoplasm (IPMN, n=7). Whole-body scan of non-respiratory-gated PET/CT was performed at first, and subsequent respiratory-gated PET/CT for one bed position was performed. All PET/CT studies were performed prior to surgery. The SUV max obtained by non-respiratory-gated PET/CT and respiratory-gated PET/CT, and percent difference in SUVmax (%SUVmax) were compared.

RESULTS

The profile curve of 5 respiratory bin image was most similar to that of static image. The third bin of 5 respiratory bin image showed highest FWHM (24.0mm) and FWTM (32.7 mm). The mean SUVmax of pancreatic cancer was similar to that of benign IPMN on non-respiratory-gated PET/CT (p=0.05), whereas significant difference was found between two groups on respiratory-gated PET/CT (p=0.016). The mean %SUV of pancreatic cancer was greater than that of benign IPMN (p<0.0001). Identification of the primary tumor in pancreatic head (n=13, 59%) was improved by using respiratory-gated PET/CT because of minimal affection of physiological accumulation in duodenum.

CONCLUSION

Respiratory-gated PET/CT is a feasible technique for evaluation of pancreatic tumors and allows more accurate identification of pancreatic tumors compared with non-respiratory-gated PET/CT.

Multimodality imaging of pancreatic ductal adenocarcinoma: a review of the literature

BACKGROUND

Accurate pre-operative imaging in pancreatic cancer helps avoid unsuccessful surgical explorations and forewarns surgeons regarding aberrant anatomy. This review aimed to determine the role of current imaging modalities in the diagnosis and determination of resectability of pancreatic and peri-ampullary adenocarcinomas.

METHODS

A systematic search of the scientific literature was carried out using EMBASE, PubMed/MEDLINE and the Cochrane Central Register of Controlled Trials for the years 1990 to 2011 to obtain access to all publications, especially randomized controlled trials, reporting on the diagnostic accuracy of ultrasonography, multi-detector computed tomography (MDCT), magnetic resonance imaging (MRI), endoscopic ultrasonography (EUS) or positron emission tomography (PET)-computed tomography (CT) and the evaluation of resectability of pancreatic and peri-ampullary adenocarcinomas.

RESULTS

Based on 66 articles analysed in the review, MDCT and MRI/MRCP have comparable sensitivity and specificity rates for diagnosis and staging of pancreatic cancers. EUS offers the best sensitivity and specificity rates for lesions <2 cm. Improved staging has been noted when PET-CT scans are added to pre-operative evaluation.

CONCLUSIONS

MDCT with angiography or MRI/MRCP should constitute the first imaging modality in suspected pancreatic adenocarcinomas. EUS is recommended for assessing lesions not clearly detected, but suspected, on CT/MRI and in tumours considered 'borderline resectable' on MDCT to assess vascular involvement. PET-CT in locally advanced lesions will help rule out distant metastases.

Pancreatic involvement by plasma cell neoplasms

INTRODUCTION

Pancreatic involvement by plasma cell neoplasms is an extremely rare event, with only 50 cases described in the literature. They can present as a primary solitary extramedullary plasmacytoma or plasmacytoma secondary to a plasma cell myeloma. Clinical manifestations are due to the presence of a pancreatic mass usually in the pancreas head, which causes extra-biliary obstruction and abdominal pain.

METHODS

Abdominal imaging including CT scan or endoscopic ultrasound with fine-needle aspiration tissue sampling is essential for the initial diagnostic procedure. However, immunohistochemical analysis of the biopsy specimen or flow cytometry of the aspirated material is crucial to prove the monoclonality and the final diagnosis of a plasma cell neoplasm.

DISCUSSION

Management of these situations include radiotherapy, chemotherapy, surgery or combined therapy. Novel medications including the immunomodulatory drugs or the proteasome inhibitors followed by consolidation with intensive chemotherapy and haematopoietic stem cell transplantation are nowadays used as upfront treatment in the cases associated to a plasma cell myeloma.

CONCLUSION

Despite the rarity, plasma cell neoplasms should be considered in the differential diagnosis of obstructive jaundice and pancreatic neoplasms since they are potentially treatable situations.

FDG PET or PET/CT in patients with pancreatic cancer: when does it add to diagnostic CT or MRI?

OBJECTIVE

Assess the impact of FDG-PET or PET/CT (PI) on pancreatic cancer management when added to CT or MRI (CDI).

MATERIALS AND METHODS

Forty-nine patients underwent 79 PI exams. Discordant findings on PI and CDI were assessed for clinical impact.

RESULTS

Fifteen of 79 PI-CDI pairs were discordant. Ten of 79 PI favorably and 5 of 79 unfavorably altered management. PI favorably altered management more often when ordered for therapy monitoring compared to staging [risk ratio 13.00 (95% CI 1.77-95.30)] or restaging [risk ratio 18.5 (95% CI 2.50-137.22)].

CONCLUSION

PI favorably alters management more often when used for therapy monitoring compared to staging or restaging.

The value of positron emission tomography/computed tomography for evaluating metastatic disease in patients with pancreatic cancer

OBJECTIVES

Routine application of positron emission tomography/computed tomography (PET/CT) for pancreatic cancer staging remains a controversial approach. The purpose of this study was to reassess the clinical impact of PET/CT for the detection of distant metastasis of pancreatic cancer.

METHODS

From January 2006 to June 2009, 125 patients with histologically proven pancreatic cancer that had undergone PET/CT at our hospital were retrospectively reviewed. To evaluate the clinical efficacy of PET/CT on the management plan, the post-PET/CT management plans were compared with the pre-PET/CT management plans.

RESULTS

After the conventional staging workup, we determined that 76 patients (60.8%) had resectable lesions, whereas 48 patients had unresectable lesions. One patient underwent explorative laparotomy due to equivocal resectability. Positron emission tomography/computed tomography diagnosed distant metastasis in only 2 (2.6%) of the 76 patients with resectable lesions, and these patients did not undergo unnecessary surgical treatment. Complete resection was not performed in 8 of the 74 operative patients because they had distant metastasis detected during the operative procedure. Positron emission tomography/computed tomography diagnosed distant metastasis in 32 of the 44 patients with metastatic lesions that were histologically shown to have sensitivity of 72.7%.

CONCLUSIONS

Positron emission tomography/computed tomography has a limited role in the evaluation of metastatic disease from pancreatic cancer.

Diagnostic value of diffusion-weighted magnetic resonance imaging compared with fluorodeoxyglucose positron emission tomography/computed tomography for pancreatic malignancy: a meta-analysis using a hierarchical regression model

BACKGROUND AND AIM

To obtain diagnostic performance of diffusion-weighted magnetic resonance imaging (DWI) and fluorine 18 fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) in the detection of pancreatic malignancy.

METHODS

We performed a meta-analysis of all available studies of the diagnostic performance of DWI and PET/CT for pancreatic malignancy. MEDLINE, EMBASE, Cochrane library and some other databases were searched for initial studies. We determined sensitivities and specificities across studies, calculated positive and negative likelihood ratios (LR+ and LR-), and constructed summary receiver operating characteristic curves (SROC) using hierarchical regression models.

RESULTS

Across 16 studies with 804 patients, PET/CT sensitivity was 0.87 (95% confidence interval [CI], 0.82, 0.81) and specificity was 0.83 (95% CI, 0.71, 0.91). Overall, LR+ was 5.84 (95% CI, 4.59, 7.42) and LR- was 0.24 (95% CI, 0.17, 0.33). DWI sensitivity was 0.85 (95% CI, 0.74, 0.92) and specificity was 0.91 (95% CI, 0.71, 0.98). LR+ was 9.53 (95% CI, 2.41, 37.65) and LR- was 0.17 (95% CI, 0.09, 0.32). In subgroup analysis, the sensitivity of enhanced versus unenhanced PET/CT in the detection of pancreatic cancer was 0.91 (95% CI, 0.86, 0.96) versus 0.84 (95% CI, 0.78, 0.90) (P > 0.05), the specificity 0.88 (95% CI, 0.73, 1.00) versus 0.81 (95% CI, 0.69, 0.94) (P > 0.05).

CONCLUSION

Positron emission tomography/computed tomography (PET/CT) was highly sensitive and DWI was a highly specific modality in diagnosing patients with pancreatic malignancy. PET/CT and DWI could play different roles in diagnosing pancreatic carcinoma. Enhanced PET/CT seems to be superior to unenhanced PET/CT. Further larger prospective studies are needed to establish its value for diagnosis in pancreatic cancer.

Pancreatic Adenocarcinoma, version 2.2012: featured updates to the NCCN Guidelines

The NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Pancreatic Adenocarcinoma discuss the workup and management of tumors of the exocrine pancreas. These NCCN Guidelines Insights provide a summary and explanation of major changes to the 2012 NCCN Guidelines for Pancreatic Adenocarcinoma. The panel made 3 significant updates to the guidelines: 1) more detail was added regarding multiphase CT techniques for diagnosis and staging of pancreatic cancer, and pancreas protocol MRI was added as an emerging alternative to CT; 2) the use of a fluoropyrimidine plus oxaliplatin (e.g., 5-FU/leucovorin/oxaliplatin or capecitabine/oxaliplatin) was added as an acceptable chemotherapy combination for patients with advanced or metastatic disease and good performance status as a category 2B recommendation; and 3) the panel developed new recommendations concerning surgical technique and pathologic analysis and reporting.

In vivo SPECT imaging with 111In-DOTA-c(RGDfK) to detect early pancreatic cancer in a hamster pancreatic carcinogenesis model

Early detection of pancreatic cancer is key to overcoming its poor prognosis. α(v)β(3)-integrin is often overexpressed in pancreatic tumor cells, whereas it is scarcely expressed in normal pancreatic cells. In this study, we investigated the usefulness of SPECT imaging with (111)In-1,4,7,10-tetraazacylododecane-N,N',N″,N'''-tetraacetic acid-cyclo-(Arg-Gly-Asp-d-Phe-Lys) [(111)In-DOTA-c(RGDfK)], an imaging probe of α(v)β(3)-integrin, for the early detection of pancreatic cancer in a hamster pancreatic carcinogenesis model.

METHODS

Hamsters were subcutaneously injected with the pancreatic duct carcinogen N-nitrosobis(2-oxopropyl)amine to induce pancreatic cancer. N-nitrosobis(2-oxopropyl)amine-treated hamsters underwent in vivo SPECT with (111)In-DOTA-c(RGDfK). After imaging, the tumor-to-normal pancreatic tissue radioactivity ratios in excised pancreatic samples were measured with autoradiography (ARG) and compared with the immunopathologic findings for α(v)β(3)-integrin. In a mouse model in which inflammation was induced with turpentine, the uptake of (111)In-DOTA-c(RGDfK) in inflammatory regions was evaluated with ARG and compared with that of (18)F-FDG.

RESULTS

(111)In-DOTA-c(RGDfK) was clearly visualized in pancreatic cancer lesions as small as 3 mm in diameter. ARG analysis revealed high tumor-to-normal pancreatic tissue radioactivity ratios (4.6 ± 1.0 [mean ± SD] in adenocarcinoma and 3.3 ± 1.4 in atypical hyperplasia). The uptake of (111)In-DOTA-c(RGDfK) strongly correlated with α(v)β(3)-integrin expression. In the inflammatory model, inflammation-to-muscle ratios for (18)F-FDG and (111)In-DOTA-c(RGDfK) were 8.37 ± 4.37 and 1.98 ± 0.60, respectively. These results imply that (111)In-DOTA-c(RGDfK) has a lower rate of false-positive tumor detection than (18)F-FDG.

CONCLUSION

Our findings suggest that SPECT with (111)In-DOTA-c(RGDfK) has great potential for the early and accurate detection of pancreatic cancer.

Positron emission tomography in hepatobiliary and pancreatic malignancies: a review

BACKGROUND

The prognosis for hepatobiliary and pancreatic malignancies is dismal. Surgery remains the primary curative option, but unresectable disease is often discovered during operative exploration. Positron emission tomography (PET) provides unique biological information different from current imaging modalities. The role of PET in detecting hepatobiliary and pancreatic malignancies has not yet been established. The purpose of this article was to review the literature on the use of PET in hepatobiliary and pancreatic malignancies.

DATA SOURCES

We performed an extensive search on PubMed using PET and hepatocellular, pancreatic, gallbladder, and cholangiocarcinoma as keywords, excluding articles not written in English or on nonhuman subjects, case reports, and series with <5 patients.

CONCLUSIONS

Although PET has shown usefulness in the diagnosis of certain cancers, current literature cautions against the use of PET for determining malignant potential of primary liver and pancreatic lesions. Literature on PET more strongly supports clinical roles for restaging of hepatobiliary and pancreatic malignancies, and for identifying metastatic disease.

Value of diffusion-weighted imaging for the discrimination of pancreatic lesions: a meta-analysis

OBJECTIVE

We aimed to explore the role of diffusion-weighted imaging (DWI) in the discrimination of pancreatic lesions through meta-analysis.

METHODS

The MEDLINE, EMBASE, Cancerlit, and Cochrane Library databases, from January 2001 to August 2011, were searched for studies evaluating the diagnostic performance of DWI in the discrimination of pancreatic lesions. We determined sensitivities and specificities across studies, calculated positive and negative likelihood ratios (LR+ and LR-), and constructed summary receiver operating characteristic curves.

RESULTS

A total of 11 studies with 586 patients, who fulfilled all of the inclusion criteria, were considered for the analysis. No publication bias was found. The pooled sensitivity of DWI was 0.86 [95% (confidence interval (CI), 0.78, 0.91] and the pooled specificity was 0.91 (95% CI, 0.81, 0.96). Overall, LR+ was 9.8 (95% CI, 4.1, 23.3) and LR- was 0.15 (95% CI, 0.09, 0.26). The area under the curve of the summary receiver operating characteristic was 0.94 (95% CI, 0.91-0.96). In subgroup analysis, prospectively designed studies had the highest pooled sensitivity (0.87, 95% CI 0.75, 0.94) and specificity (0.96, 95% CI 0.91, 0.99) (P<0.05). Study sensitivity was not correlated with the prevalence of pancreatic lesions (R=0.1076, P=0.3247).

CONCLUSION

A limited number of small studies suggest that DWI is a potentially technically feasible measure to differentiate malignant from benign pancreatic lesions. However, it is still controversial and is limited in that it can only distinguish certain lesions. High-quality prospective studies on DWI for the discrimination of pancreatic lesions still need to be conducted.