Thyroid poorly differentiated carcinoma metastatic to pancreas diagnosed by fine-needle aspiration and demonstrating a novel BRAF fusion.

Differentiating pancreatic duct adenocarcinoma from metastasis can be challenging by morphology alone. Metastasis from a classic papillary thyroid carcinoma can present as a poorly differentiated carcinoma and mimic pancreatic ductal adenocarcinoma's morphology.

IK Channel-Independent Effects of Clotrimazole and Senicapoc on Cancer Cells Viability and Migration.

Many studies highlighted the importance of the IK channel for the proliferation and the migration of different types of cancer cells, showing how IK blockers could slow down cancer growth. Based on these data, we wanted to characterize the effects of IK blockers on melanoma metastatic cells and to understand if such effects were exclusively IK-dependent. For this purpose, we employed two different blockers, namely clotrimazole and senicapoc, and two cell lines: metastatic melanoma WM266-4 and pancreatic cancer Panc-1, which is reported to have little or no IK expression. Clotrimazole and senicapoc induced a decrease in viability and the migration of both WM266-4 and Panc-1 cells irrespective of IK expression levels. Patch-clamp experiments on WM266-4 cells revealed Ca2+-dependent, IK-like, clotrimazole- and senicapoc-sensitive currents, which could not be detected in Panc-1 cells. Neither clotrimazole nor senicapoc altered the intracellular Ca2+ concentration. These results suggest that the effects of IK blockers on cancer cells are not strictly dependent on a robust presence of the channel in the plasma membrane, but they might be due to off-target effects on other cellular targets or to the blockade of IK channels localized in intracellular organelles.

Preoperative maximum standardized uptake value and carbohydrate antigen 19-9 were independent predictors of pathological stages and overall survival in Chinese patients with pancreatic duct adenocarcinoma.

BACKGROUND: Purpose of this study was to analyze whether preoperative maximum standardized uptake value (SUVmax) and carbohydrate antigen 19-9 (CA19-9) levels might provide prognostic information in Chinese patients with pancreatic duct adenocarcinoma (PDAC) after pancreaticoduodenectomy (PD). METHODS: Standard PD was performed on 109 patients with PDAC by the same operative team, and all patients received preoperative positron emission tomography/computed tomography examination and blood test. RESULTS: Patients had a mean age of 59 ± 9.35 years. Females accounted for 38.5%. Mean levels of SUVmax, carcino-embryonic antigen (CEA) and CA19-9 were 5.70 ± 2.76, 3.95 ± 4.16ng/mL and 321.62 ± 780.71kU/L. In univariate Logistic regression analysis, preoperative SUVmax, CEA and CA19-9 levels (p < 0.05 for all) rather than other preoperative variables (p > 0.05 for all) were significantly related to AJCC stages. Multivariate Logistic regression analysis showed that preoperative SUVmax and CA19-9 levels (p < 0.05 for all) rather than other preoperative variables (p > 0.05 for all) were significantly associated with AJCC stages. Mean overall survival (OS) was 21 ± 14.50 months. In univariate Cox regression analysis, age, SUVmax, CEA and CA19-9 levels before operation (p < 0.05 for all) rather than other preoperative variables (p > 0.05 for all) were significantly related to OS. Multivariate Cox regression analysis showed that age, SUVmax and CA19-9 levels before operation (p < 0.05 for all) rather than other preoperative variables (p > 0.05 for all) were significantly associated with OS. CONCLUSIONS: This study demonstrated that preoperative SUVmax and CA19-9 levels independently predicted pathological stages and OS of patients with PDAC after PD. These preoperative variables might have significant prognostic implication in patients with PDAC after PD. Patients with abnormal SUVmax and CA19-9 levels should be paid special attention to in operative strategy and perioperative management.

MicroRNA-140 regulates cell growth and invasion in pancreatic duct adenocarcinoma by targeting iASPP.

MicroRNAs are ∼22 nucleotide RNAs processed from RNA hairpin structures that play important roles in regulating protein expression level via binding to mRNA, either suppressing its translation or speeding up its degradation. In humans, they regulate most protein-coding genes, including genes important in cancer and other diseases. In this study, the expression of microRNA-140 (miR-140) was demonstrated to be significantly suppressed in pancreatic duct adenocarcinoma specimens and cell lines, compared with their adjacent normal tissues. With the help of bioinformatics analysis, inhibitor of apoptosis-stimulating protein of p53 (iASPP) was identified to be a direct target of miR-140, and luciferase reporter experiment confirmed this discovery. Overexpression of miR-140 decreases the protein expressions of iASPP, ΔNp63, MMP2, and MMP9. Growth and invasion of PANC-1 cells were attenuated by overexpression of miR-140 in vitro. The suppressive effect of miR-140 on PANC-1 cell line could be partly balanced out by manual overexpression of iASPP. Above all, these findings provided insights into the functional mechanism of miR-140, suggested that the miR-140/iASPP axis may interfere with the proliferative and invasive property of pancreatic duct adenocarcinoma cells, and indicated that miR-140 could be a potential therapeutic target for pancreatic duct adenocarcinoma.

Role of neoadjuvant therapy for nonmetastatic pancreatic cancer: Current evidence and future perspectives.

Pancreatic adenocarcinoma (PDAC) is one of the most common and lethal human cancers worldwide. Surgery followed by adjuvant chemotherapy offers the best chance of a long-term survival for patients with PDAC, although only approximately 20% of the patients have resectable tumors when diagnosed. Neoadjuvant chemotherapy (NACT) is recommended for borderline resectable pancreatic cancer. Several studies have investigated the role of NACT in treating resectable tumors based on the recent advances in PDAC biology, as NACT provides the potential benefit of selecting patients with favorable tumor biology and controls potential micro-metastases in high-risk patients with resectable PDAC. In such challenging cases, new potential tools, such as ct-DNA and molecular targeted therapy, are emerging as novel therapeutic options that may improve old paradigms. This review aims to summarize the current evidence regarding the role of NACT in treating non-metastatic pancreatic cancer while focusing on future perspectives in light of recent evidence.

Fatty infiltration of the pancreas: a systematic concept analysis.

Fatty infiltration of the pancreas (FIP) has been recognized for nearly a century, yet many aspects of this condition remain unclear. Regular literature reviews on the diagnosis, consequences, and management of FIP are crucial. This review article highlights the various disorders for which FIP has been established as a risk factor, including type 2 diabetes mellitus (T2DM), pancreatitis, pancreatic fistula (PF), metabolic syndrome (MS), polycystic ovary syndrome (PCOS), and pancreatic duct adenocarcinoma (PDAC), as well as the new investigation tools. Given the interdisciplinary nature of FIP research, a broad range of healthcare specialists are involved. This review article covers key aspects of FIP, including nomenclature and definition of pancreatic fat infiltration, history and epidemiology, etiology and pathophysiology, clinical presentation and diagnosis, clinical consequences, and treatment. This review is presented in a detailed narrative format for accessibility to clinicians and medical students.

Prognosis prediction and comparison between pancreatic signet ring cell carcinoma and pancreatic duct adenocarcinoma: a retrospective observational study.

Background: Pancreatic signet ring cell carcinoma (PSRCC) is a rare and aggressive cancer that has been reported primarily as case reports. Due to limited large-scale epidemiological and prognostic analyses, the outcomes of PSRCC patients varies greatly in the absence of recognized first-line treatment strategies. This study aimed to compare the clinical features, treatment, and prognosis of PSRCC and pancreatic ductal cell carcinoma (PDAC), the most common subtype of pancreatic cancer, and to establish predictive models for these subtypes. Methods: The data on PSRCC and PDAC patients from 1998 to 2018 was obtained from the Surveillance, Epidemiology, and End Results (SEER) database. Thereafter, the clinical, demographic, and treatment characteristics of the two groups and the differences and influencing factors of the two groups were evaluated by propensity score matching (PSM), Kaplan-Meier survival curves, Cox risk regression analyses, and least absolute shrinkage and selection operator (LASSO) analysis. Next, prognosis models were constructed and validated by KM and ROC analysis. Finally, a nomogram was constructed, based on the results of these analyses, to predict survival outcomes of PSRCC and PDAC patients. Results: A total of 84,789 patients (432 PSRCC and 84357 PDAC patients) were included in this study. The results of the study revealed that, compared to the PDAC patients, PSRCC patients were more likely to be male, aged between 58-72 years, have larger tumor masses, and less likely to undergo chemotherapy. Before PSM, the overall survival and cancer-specific survival of the PSRCC group were significantly lower than those PDAC group, but there was no difference in the prognosis of the two groups after PSM. Additionally, lymph node ratio (LNR), log odds of positive lymph node (LODDS), tumor size, age, T-stage, marital status, and summary stage were found to be independent prognostic factors for PSRCC. Lastly, the prediction model and nomogram based on these prognostic factors could accurately predict the survival rate of the patients in SEER datasets and external validation datasets. Conclusion: The prognosis of PSRCC and PDAC patients is similar under the same conditions; however, PSRCC patients may have more difficulty in receiving better treatment, thus resulting in their poor prognosis.

BK Channel in the Physiology and in the Cancer of Pancreatic Duct: Impact and Reliability of BK Openers.

BK (KCa 1.1, Slo-1) is a K+ channel characterized by an allosteric regulation of the gating mechanism by Ca2+ binding and voltage, and a high unitary conductance. The channel is expressed in many different tissues, where it is involved in the regulation or the fine-tuning of many physiological processes. Among other organs, BK is expressed in the pancreatic duct, a part of the gland important for the correct ionic composition of the pancreatic juice. Unfortunately, the pancreatic duct is also the site where one of the deadliest cancer types, the pancreatic duct adenocarcinoma (PDAC), develops. In the past years, it has been reported that continuous exposure of cancer cells to BK openers can have a significant impact on cell viability as well as on the ability to proliferate and migrate. Here, we first summarize the main BK channel properties and its roles in pancreatic duct physiology. Then we focus on the potential role of BK as a pharmacological target in PDAC. Moreover, we discuss how results obtained when employing BK activators on cancer cells can, in some cases, be misleading.

The VRAC blocker DCPIB directly gates the BK channels and increases intracellular Ca2+ in melanoma and pancreatic duct adenocarcinoma cell lines.

BACKGROUND AND PURPOSE: The volume regulated anion channel (VRAC) is known to be involved in different aspects of cancer cell behaviour and response to therapies. For this reason, we investigated the effect of DCPIB, a presumably specific blocker of VRAC, in two types of cancer: pancreatic duct adenocarcinoma (PDAC) and melanoma. EXPERIMENTAL APPROACH: We used patch-clamp electrophysiology, supported by Ca2+ imaging, gene expression analysis, docking simulation and mutagenesis. We employed two PDAC lines (Panc-1 and MiaPaCa-2), as well as a primary (IGR39) and a metastatic (IGR37) melanoma line. KEY RESULTS: DCPIB markedly increased whole-cell currents in Panc-1, MiaPaca2 and IGR39, but not in IGR37 cells. The currents were mostly mediated by KCa 1.1 channels, commonly known as BK channels. We confirmed DCPIB activation of BK channels also in HEK293 cells transfected with α subunits of this channel. Further experiments showed that in IGR39, and to a smaller degree also in Panc-1 cells, DCPIB induced a rapid Ca2+ influx. This, in turn, indirectly potentiated BK channels and, in IGR39 cells, additionally activated other Ca2+ -dependent channels. However, Ca2+ influx was not required for activation of BK channels by DCPIB, as such activation involved the extracellular part of the protein and we have identified a residue crucial for binding. CONCLUSION AND IMPLICATIONS: DCPIB directly targeted BK channels and, also, acutely increased intracellular Ca2+ . Our findings extend the list of DCPIB effects that should be taken into consideration for future development of DCPIB-based modulators of ion channels and other membrane proteins.

The EUS molecular evaluation of pancreatic cancer: A prospective multicenter cohort trial.

BACKGROUND AND OBJECTIVES: Patients with locally advanced or metastatic pancreatic ductal adenocarcinoma (A-PDAC) are not candidates for surgical resection and are often offered palliative chemotherapy. The ready availability of a safe and effective tumor sampling technique to provide material for both diagnosis and comprehensive genetic profiling is critical for informing precision medicine in A-PDAC, thus potentially increasing survival. The aim of this study is to examine the feasibility and benefits of routine comprehensive genomic profiling (CGP) of A-PDAC using EUS-FNA material. METHODS: This is a prospective cohort study to test the clinical utility of fresh frozen or archival EUS-FNA samples in providing genetic material for CGP. The results of the CGP will be reviewed at a molecular tumor board. The proportion of participants that have a change in their treatment recommendations based on their individual genomic profiling will be assessed. Correlations between CGP and stage, prognosis, response to treatment and overall survival will also be investigated. This study will open to recruitment in 2020, with a target accrual of 150 A-PDAC patients within 36 months, with a 2-year follow-up. It is expected that the majority of participants will be those who have already consented for their tissue to be biobanked in the Victorian Pancreatic Cancer Biobank at the time of diagnostic EUS-FNA. Patients without archival or biobanked material that is suitable for CGP may be offered a EUS-FNA procedure for the purposes of obtaining fresh frozen material. DISCUSSION: This trial is expected to provide crucial data regarding the feasibility of routine CGP of A-PDAC using EUS-FNA material. It will also provide important information about the impact of this methodology on patients' survival.

DNA Damage Repair Deficiency in Pancreatic Ductal Adenocarcinoma: Preclinical Models and Clinical Perspectives.

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal cancers worldwide, and survival rates have barely improved in decades. In the era of precision medicine, treatment strategies tailored to disease mutations have revolutionized cancer therapy. Next generation sequencing has found that up to a third of all PDAC tumors contain deleterious mutations in DNA damage repair (DDR) genes, highlighting the importance of these genes in PDAC. The mechanisms by which DDR gene mutations promote tumorigenesis, therapeutic response, and subsequent resistance are still not fully understood. Therefore, an opportunity exists to elucidate these processes and to uncover relevant therapeutic drug combinations and strategies to target DDR deficiency in PDAC. However, a constraint to preclinical research is due to limitations in appropriate laboratory experimental models. Models that effectively recapitulate their original cancer tend to provide high levels of predictivity and effective translation of preclinical findings to the clinic. In this review, we outline the occurrence and role of DDR deficiency in PDAC and provide an overview of clinical trials that target these pathways and the preclinical models such as 2D cell lines, 3D organoids and mouse models [genetically engineered mouse model (GEMM), and patient-derived xenograft (PDX)] used in PDAC DDR deficiency research.

Enhancement of Antitumor Efficacy of Paclitaxel-Loaded PEGylated Liposomes by N,N-Dimethyl Tertiary Amino Moiety in Pancreatic Cancer.

INTRODUCTION: Pancreatic cancer, or pancreatic duct adenocarcinoma (PDAC), remains one of the most lethal cancers and features insidious onset, highly aggressive behavior and early distant metastasis. The dense fibrotic stroma surrounding tumor cells is thought to be a shield to resist the permeation of chemotherapy drugs in the treatment of PDAC. Thus, we synthesized a pancreas-targeting paclitaxel-loaded PEGylated liposome and investigated its antitumor efficacy in the patient-derived orthotopic xenograft (PDOX) nude mouse models of PDAC. METHODS: The PTX-loaded PEGylated liposomes were prepared by film dispersion-ultrasonic method and modified by an N,N-dimethyl tertiary amino residue. Morphology characteristics of the PTX-loaded liposomes were observed by transmission electron microscope (TEM). The PDOX models of PDAC were established by orthotopic implantation and imaged by a micro positron emission tomography/computed tomography (PET/CT) imaging system. The in vivo distribution and antitumor study were then carried out to observe the pancreas-targeting accumulation and the antitumor efficacy of the proposed PTX liposomes. RESULTS: PTX loaded well into both modified (PTX-Lip2N) and unmodified (PTX-Lip) PEGylated liposomes with spherical shapes and suitable parameters for the endocytosis process. The PDOX nude mouse models were successfully created in which high 18F-FDG intaking regions were observed by micro-PET/CT. In addition to higher cellular uptakes of PTX-Lip2N by the BxPC-3 cells, the proposed nanoparticle had a notable penetrating ability towards PDAC tumor tissues, and consequently, the antitumor ability of PTX-Lip2N was significantly superior to the unmodified PTX-Lip in vivo PDOX models and even more effective than nab-PTX in restraining tumor growth. CONCLUSION: The modified pancreas-targeting PTX-loaded PEGylated liposomes provide a promising platform for the treatment of pancreatic cancer.

Biochemical Predictors of Response to Neoadjuvant Therapy in Pancreatic Ductal Adenocarcinoma.

Pancreatic ductal adenocarcinoma (PDAC) is becoming increasingly more common. Treatment for PDAC is dependent not only on stage at diagnosis, but complex anatomical relationships. Recently, the therapeutic approach to this disease has shifted from upfront surgery for technically resectable lesions to a neoadjuvant therapy first approach. Selecting an appropriate regimen and determining treatment response is crucial for optimal oncologic outcome, especially since radiographic imaging has proven unreliable in this setting. Tumor biomarkers have the potential to play a key role in treatment planning, treatment monitoring, and surveillance as an adjunct laboratory test. In this review, we will discuss common chemotherapeutic options, mechanisms of resistance, and potential biomarkers for PDAC. The aim of this paper is to present currently available biomarkers for PDAC and to discuss how these markers may be affected by neoadjuvant chemotherapy treatment. Understanding current chemotherapy regiments and mechanism of resistance can help us understand which markers may be most affected and why; therefore, determining to what ability we can use them as a marker for treatment progression, prognosis, or potential relapse.

Prognostic factors for long-term survival after pancreaticoduodenectomy for periampullary adenocarcinoma. A retrospective cohort study.

BACKGROUND: Periampullary adenocarcinoma (PAAC) had a poor prognosis, and pancreaticoduodenectomy (PD) remains the only potentially curative treatment. The study aimed to identify the impact of different clinicopathological factors on long-term survival following PD for PAAC. PATIENTS AND METHODS: This study is a retrospective cohort study for the patients who underwent PD for pathologically proven PAAC from January 2010 to January 2019. Statistical analysis was done using Cox regression multivariate analyses for independent risk factors for survival. RESULT: There were 137 patients with PAAC who underwent PD, 79 patients (57.7%) underwent pylorus-preserving PD. Pancreatico-jejunostomy was done in 108 patients (78.8%). The primary analysis showed that risk factors for poor long-term survival include patients with co-morbidities like hypertension or ischemic heart disease, Carbohydrate Antigen 19-9 > 400U/ml, tumor size > 3 cm, poor tumor differentiation, positive lymph nodes invasion, lymphovascular invasion, and Perineural invasion. Multivariate analysis demonstrated that large tumor size > 3 cm (HR: 0.177, 95%CI: 0.084-0.374, P = 0.002), poorly differentiated tumor (HR: 0.059, 95%CI: 0.020-0.0174, P = 0.016), and perineural invasion in the pathological study (HR: 0.101, 95%CI: 0.046-0.224, P = 0.006) were independent risk factors for poor 5-years survival. The prognosis was better in ampullary adenocarcinoma (5-year survival was 42.1%) than pancreatic adenocarcinoma (5-year survival was 24.3%). The 1, 3, 5 and 7-year overall survival rates were 84.5%, 57.4%, 35.9% and 20.1% respectively. CONCLUSION: It seems from the current study that Tumor size > 3 cm, poor tumor differentiation, and Perineural invasion were independent predictors of poor survival in patients with PAAC.

Identification of potential hub genes associated with the pathogenesis and prognosis of pancreatic duct adenocarcinoma using bioinformatics meta-analysis of multi-platform datasets.

Pancreatic duct adenocarcinoma (PDAC) is a highly malignant type of cancer with a low five-year survival rate. Gene alterations are crucial to the molecular pathogenesis of PDAC. Therefore, the present study analyzed gene expression profiles to reveal genes involved in the tumorigenesis of PDAC. A total of eight gene expression profiles (GSE15471, GSE16515, GSE41368, GSE62165, GSE62452, GSE71729, GSE71989 and GSE91035) and a PDAC dataset were acquired from the Gene Expression Omnibus and The Cancer Genome Atlas (TCGA) database, respectively. Differentially expressed genes (DEGs) were screened using functional annotation, Gene Ontology (GO) enrichment analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis and protein-protein interaction (PPI) network construction. A Cox proportional hazards model was then constructed and used to analyze the data. A total of 136 DEGs (67 up- and 69 downregulated genes) were identified between PDAC tissues and normal tissues. The 'extracellular matrix-related' genes were the most enriched in the GO term analysis. 'Pancreatic secretion', 'phosphoinositide-3-kinase-protein kinase B/Akt (PI3K-Akt) signaling pathway', 'protein digestion and absorption' and 'ECM-receptor interaction' were the most enriched categories in KEGG pathway analysis. Following PPI network construction, the 10 most significant genes [albumin, epidermal growth factor, matrix metalloproteinase (MMP) 9, epidermal growth factor receptor, fibronectin 1, MMP1, plasminogen activator inhibitor-1, tissue inhibitor of metalloproteinase 1, plasminogen activator urokinase (PLAU) and PLAU receptor) exhibiting a high degree of connectivity, were identified as the hub genes likely to be associated with the pathogenesis of PDAC. In addition, a prognostic predictive system for PDAC, composed of five genes (laminin subunit γ 2, laminin subunit ß 3, serpin family B member 5, amphiregulin and secreted frizzled related protein 4), was constructed. This was validated in the GSE62452 dataset (using 66 PDAC samples with outcome data) and TCGA PDAC dataset (using 146 PDAC samples with outcome data). In conclusion, the present study revealed potential hub genes involved in PDAC progression, providing directive significance for individualized clinical decision-making and molecular-targeting therapy in patients with PDAC.

Novel Mitochondria-Targeted Furocoumarin Derivatives as Possible Anti-Cancer Agents.

Targeting small molecules to appropriate subcellular compartments is a way to increase their selectivity and effectiveness while minimizing side effects. This can be accomplished either by stably incorporating specific "homing" properties into the structure of the active principle, or by attaching to it a targeting moiety via a labile linker, i.e., by producing a "targeting pro-drug." Mitochondria are a recognized therapeutic target in oncology, and blocking the population of the potassium channel Kv1.3 residing in the inner mitochondrial membrane (mtKv1.3) has been shown to cause apoptosis of cancerous cells expressing it. These concepts have led us to devise novel, mitochondria-targeted, membrane-permeant drug candidates containing the furocoumarin (psoralenic) ring system and the triphenylphosphonium (TPP) lipophilic cation. The strategy has proven effective in various cancer models, including pancreatic ductal adenocarcinoma, melanoma, and glioblastoma, stimulating us to devise further novel molecules to extend and diversify the range of available drugs of this type. New compounds were synthesized and tested in vitro; one of them-a prodrug in which the coumarinic moiety and the TPP group are linked by a bridge comprising a labile carbonate bond system-proved quite effective in in vitro cytotoxicity assays. Selective death induction is attributed to inhibition of mtKv1.3. This results in oxidative stress, which is fatal for the already-stressed malignant cells. This compound may thus be a candidate drug for the mtKv1.3-targeting therapeutic approach.

Superparamagnetic iron oxide nanoparticles for MR imaging of pancreatic cancer: Potential for early diagnosis through targeted strategies.

Superparamagnetic iron oxide nanoparticles (SPION)-based magnetic resonance imaging is a powerful, noninvasive tool in biomedical imaging. The recent embedding of SPIO in nanoencapsulations that had different controllable surface properties has now made it possible to use SPIO in the imaging of metabolic processes. The two major issues to realize maximized and selective SPIO cancer targeting are the minimization of macrophage uptake and the preferential binding to cancerous cells over healthy neighbor cells. The utility of SPIO has been shown in clinical applications using a series of marketed SPION-based contrast agents. Applications have ranged from detecting inflammatory diseases to the specific identification of cell surface markers expressed on tumors. This review focuses on iron-oxide-based nanoparticles, to include the physiochemical properties of SPION surface engineering and its synthetic methods as well as SPIO imaging applications and specifically targeted SPIO conjugates (e.g. targeted probes) for labeling cancerous, cell-surface molecules. As a specific application of this technology, we discuss its use in the imaging of pancreatic duct adenocarcinoma in addition to its potential for use in early diagnosis through targeted strategies.

CRABP-II is a highly sensitive and specific diagnostic molecular marker for pancreatic ductal adenocarcinoma in distinguishing from benign pancreatic conditions.

CRABP-II, a retinoic acid binding protein, shuffles retinoic acid from cytoplasm into nucleus and forms a complex with nuclear retinoic acid receptor to facilitate transcriptional activities of retinoic acid. In this study, we studied the expression patterns of CRABP-II in pancreatic ductal adenocarcinoma (PDAC) compared with those in normal pancreas, chronic pancreatitis, and precancerous lesions. We showed no detectable expressions of CRABP-II in normal pancreatic parenchyma, normal ductal epithelium, and chronic pancreatitis. In contrast, the expression of CRABP-II was readily detected in all PDACs including metastatic PDACs. CRABP-II staining was also observed and progressively increased from pancreatic intraepithelial neoplasia 1 to 3. In addition, when fine needle aspiration specimens were evaluated from patients with PDAC, CRABP-II was positive in 55.6% cases if cytology diagnosis was "atypia," and in 87.5% cases, if "malignancy." Our study suggests that CRABP-II is highly and specifically expressed in PDAC and is more commonly expressed in high-grade precursor cancerous lesions than in low-grade lesions. Therefore, overexpression of CRABP-II is a late event of pancreatic carcinogenesis, and it could be used as a diagnostic marker to distinguish PDAC from other benign pancreatic conditions in both resection and cytology specimens.