Imaging preoperatively for pancreatic adenocarcinoma

Imaging of pancreatic ductal adenocarcinoma - An update for all stages of patient management

Background

Pancreatic ductal adenocarcinoma (PDAC) is a common and lethal cancer. From diagnosis to disease staging, response to neoadjuvant therapy assessment and patient surveillance after resection, imaging plays a central role, guiding the multidisciplinary team in decision-planning.

Review aims and findings

This review discusses the most up-to-date imaging recommendations, typical and atypical findings, and issues related to each step of patient management. Example cases for each relevant condition are presented, and a structured report for disease staging is suggested.

Conclusion

Despite current issues in PDAC imaging at different stages of patient management, the radiologist is essential in the multidisciplinary team, as the conveyor of relevant imaging findings crucial for patient care.

Use of individualized 3D-printed models of pancreatic cancer to improve surgeons' anatomic understanding and surgical planning

OBJECTIVES

Three-dimensional (3D) printing has been increasingly used to create accurate patient-specific 3D-printed models from medical imaging data. We aimed to evaluate the utility of 3D-printed models in the localization and understanding of pancreatic cancer for surgeons before pancreatic surgery.

METHODS

Between March and September 2021, we prospectively enrolled 10 patients with suspected pancreatic cancer who were scheduled for surgery. We created an individualized 3D-printed model from preoperative CT images. Six surgeons (three staff and three residents) evaluated the CT images before and after the presentation of the 3D-printed model using a 7-item questionnaire (understanding of anatomy and pancreatic cancer [Q1-4], preoperative planning [Q5], and education for trainees or patients [Q6-7]) on a 5-point scale. Survey scores on Q1-5 before and after the presentation of the 3D-printed model were compared. Q6-7 assessed the 3D-printed model's effects on education compared to CT. Subgroup analysis was performed between staff and residents.

RESULTS

After the 3D-printed model presentation, survey scores improved in all five questions (before 3.90 vs. after 4.56, p < 0.001), with a mean improvement of 0.57‒0.93. Staff and resident scores improved after a 3D-printed model presentation (p < 0.05), except for Q4 in the resident group. The mean difference was higher among the staff than among the residents (staff: 0.50‒0.97 vs. residents: 0.27‒0.90). The scores of the 3D-printed model for education were high (trainees: 4.47 vs. patients: 4.60) compared to CT.

CONCLUSION

The 3D-printed model of pancreatic cancer improved surgeons' understanding of individual patients' pancreatic cancer and surgical planning.

CLINICAL RELEVANCE STATEMENT

The 3D-printed model of pancreatic cancer can be created using a preoperative CT image, which not only assists surgeons in surgical planning but also serves as a valuable educational resource for patients and students.

KEY POINTS

• A personalized 3D-printed pancreatic cancer model provides more intuitive information than CT, allowing surgeons to better visualize the tumor's location and relationship to neighboring organs. • In particular, the survey score was higher among staff who performed the surgery than among residents. • Individual patient pancreatic cancer models have the potential to be used for personalized patient education as well as resident education.

Tumour origin, diagnostic accuracy and histopathological evaluation in patients with periampullary cancer: nationwide cohort study

BACKGROUND

The prevalence of different periampullary cancers (pancreatic ductal adenocarcinoma, distal cholangiocarcinoma, ampullary cancer and duodenal cancer) is heterogeneous in the literature. During the 2010s, a standardized histopathological protocol for pancreatoduodenectomy specimens based on axial slicing was adopted in Sweden. The present study sought to provide information about periampullary cancers with regard to tumour types in curative and noncurative settings, preoperative diagnostic accuracy and the impact of a standardized evaluation of the surgical specimen on diagnosis, R status and lymph node assessment.

METHODS

Data from patients diagnosed with periampullary cancer from 2010 to 2019 were retrieved from the Swedish National Registry for Pancreatic and Periampullary Cancer.

RESULTS

Among non-curative patients, 3704 (83.6 per cent) were diagnosed with pancreatic ductal adenocarcinoma. Among patients treated with pancreatoduodenectomy, diagnosis was pancreatic ductal adenocarcinoma in 1380 (50.0 per cent), distal cholangiocarcinoma in 284 (10.3 per cent), ampullary cancer in 376 (13.6 per cent), duodenal cancer in 160 (5.8 per cent) and other diagnoses in 560 (20.3 per cent) patients. The preoperative diagnosis corresponded to the postoperative in 1177 (67.5 per cent) patients for pancreatic ductal adenocarcinoma, 162 (37.4 per cent) patients for distal cholangiocarcinoma, 220 (61.3 per cent) patients for ampullary cancer and 120 (53.6 per cent) patients for duodenal cancer. A higher rate of pancreatic ductal adenocarcinoma was seen in surgical specimens who underwent standardized evaluation, from 56.8 per cent to 64.3 per cent (P = 0.003). After standardization, higher rates of R1 resection (31.7 per cent versus 44.6 per cent, P < 0.001) and N1 stage (62.1 per cent versus 77.0 per cent, P < 0.001) were found.

CONCLUSION

The proportion of pancreatic ductal adenocarcinoma was higher in patients in a non-curative setting compared with patients who underwent surgery. The rate of misdiagnosis for periampullary cancers was confirmed to be high. Thus, it should be taken into account when preoperative oncological treatment is considered. Standardized evaluation of the surgical specimen has increased pancreatic ductal adenocarcinoma, R1 and N1 rates.

Machine learning was used to predict risk factors for distant metastasis of pancreatic cancer and prognosis analysis

BACKGROUND

The mechanisms of distant metastasis in pancreatic cancer (PC) have not been elucidated, and this study aimed to explore the risk factors affecting the metastasis and prognosis of metastatic patients and to develop a predictive model.

METHOD

Clinical data from patients meeting criteria from 1990 to 2019 were obtained from the Surveillance, Epidemiology, and End Results (SEER) database, and two machine learning methods, random forest and support vector machine, combined with logistic regression, were used to explore risk factors influencing distant metastasis and to create nomograms. The performance of the model was validated using calibration curves and ROC curves based on the Shaanxi Provincial People's Hospital cohort. LASSO regression and Cox regression models were used to explore the independent risk factors affecting the prognosis of patients with distant PC metastases.

RESULTS

We found that independent risk factors affecting PC distant metastasis were: age, radiotherapy, chemotherapy, T and N; the independent risk factors for patient prognosis were: age, grade, bone metastasis, brain metastasis, lung metastasis, radiotherapy and chemotherapy.

CONCLUSION

Together, our study provides a method for risk factors and prognostic assessment for patients with distant PC metastases. The nomogram we developed can be used as a convenient individualized tool to facilitate aid in clinical decision making.

Detection of pancreatic cancer with two- and three-dimensional radiomic analysis in a nationwide population-based real-world dataset

BACKGROUND

CT is the major detection tool for pancreatic cancer (PC). However, approximately 40% of PCs < 2 cm are missed on CT, underscoring a pressing need for tools to supplement radiologist interpretation.

METHODS

Contrast-enhanced CT studies of 546 patients with pancreatic adenocarcinoma diagnosed by histology/cytology between January 2005 and December 2019 and 733 CT studies of controls with normal pancreas obtained between the same period in a tertiary referral center were retrospectively collected for developing an automatic end-to-end computer-aided detection (CAD) tool for PC using two-dimensional (2D) and three-dimensional (3D) radiomic analysis with machine learning. The CAD tool was tested in a nationwide dataset comprising 1,477 CT studies (671 PCs, 806 controls) obtained from institutions throughout Taiwan.

RESULTS

The CAD tool achieved 0.918 (95% CI, 0.895-0.938) sensitivity and 0.822 (95% CI, 0.794-0.848) specificity in differentiating between studies with and without PC (area under curve 0.947, 95% CI, 0.936-0.958), with 0.707 (95% CI, 0.602-0.797) sensitivity for tumors < 2 cm. The positive and negative likelihood ratios of PC were 5.17 (95% CI, 4.45-6.01) and 0.10 (95% CI, 0.08-0.13), respectively. Where high specificity is needed, using 2D and 3D analyses in series yielded 0.952 (95% CI, 0.934-0.965) specificity with a sensitivity of 0.742 (95% CI, 0.707-0.775), whereas using 2D and 3D analyses in parallel to maximize sensitivity yielded 0.915 (95% CI, 0.891-0.935) sensitivity at a specificity of 0.791 (95% CI, 0.762-0.819).

CONCLUSIONS

The high accuracy and robustness of the CAD tool supported its potential for enhancing the detection of PC.

Genome‑wide DNA hypomethylation drives a more invasive pancreatic cancer phenotype and has predictive occult distant metastasis and prognosis potential

Genome‑wide DNA hypomethylation is the most common molecular feature in human cancers associated with chromosomal instability (CIN), which is involved in the mechanisms that regulate pancreatic cancer (PC) metastasis. It was investigated whether genome‑wide DNA hypomethylation affects the phenotype in PC via CIN in vitro, and its significance on the biological behavior of PC was verified. The relative demethylation level (RDL) of long interspersed nucleotide element‑1 (LINE‑1) in human PC cell lines was used to characterize DNA hypomethylation using methylation‑specific quantitative (q)PCR. CIN was estimated by changes in chromosomal copy number using comparative genomic hybridization analysis. Abnormal segregation of chromosomes was assessed by immunocytochemistry, and the DNA damage response was evaluated using the number of anti‑γH2AX positive cells. Invasion ability was assessed using a Matrigel invasion assay. Clinical specimens from 49 patients with PC who underwent curative surgery were evaluated for a correlation of DNA hypomethylation with clinical outcome. Successful induction of genome‑wide DNA hypomethylation in PC cells led to copy number changes in specific chromosomal regions. The number of cells with abnormal segregation of chromosomes significantly increased with the number of anti‑γH2AX positive cells. The invasive potential of these cells also significantly increased. The occurrence of occult distant metastasis in the clinical specimens and receiver operating characteristic analysis clearly identified those who were and were not likely to have occult distant metastasis, with high LINE‑1 RDL significantly correlated with the presence of occult distant metastasis (P=0.035) and poor prognosis (P=0.048). The significance of genome‑wide DNA hypomethylation on the biological behavior of PC, which promotes a more invasive phenotype via CIN in vitro and predicts the susceptibility to occult distant metastasis and poor prognosis in patients with PC was revealed.

Prognosis and Clinical Characteristics of Patients with Pancreatic Ductal Adenocarcinoma Diagnosed by Endoscopic Ultrasonography but Indeterminate on Computed Tomography

Background/Aims

Endoscopic ultrasonography (EUS) provides high-resolution images and is superior to computed tomography (CT) scan in diagnosing small pancreatic ductal adenocarcinoma (PDAC). As a result, the use of EUS for early detection of PDAC has attracted attention. This study aimed to identify the clinical and radiological characteristics of patients with PDAC diagnosed by EUS but not found on CT scan.

Methods

The medical records of patients diagnosed with PDAC at 12 tertiary referral centers in Korea from January 2003 to April 2019 were reviewed. This study included patients with pancreatic masses not clearly observed on CT scan but identified on EUS. The clinical characteristics and radiological features of the patients were analyzed, and survival analysis was performed.

Results

A total of 83 patients were enrolled. The most common abnormal CT findings other than a definite mass was pancreatic duct dilatation, which was identified in 61 patients (73.5%). All but four patients underwent surgery. The final pathologic stages were as follows: IA (n=31, 39.2%), IB (n=8, 10.1%), IIA (n=20, 25.3%), IIB (n=17, 21.5%), III (n=2, 2.5%), and IV (n=1, 1.4%). The 5-year survival rate of these patients was 50.6% (95% confidence interval, 38.8% to 66.7%). Elevated liver function testing and R1 resection emerged as significant predictors of mortality in the multivariable Cox regression analysis.

Conclusions

This multicenter study demonstrated favorable long-term prognosis in patients with PDAC diagnosed by EUS but indeterminate on CT scan. EUS should be considered for patients with suspected PDAC but indeterminate on CT scan.

The Performance Comparison of 18F-FDG PET/MRI and 18F-FDG PET/CT for the Identification of Pancreatic Neoplasms

PURPOSE

To determine the optimal imaging tool for clinical evaluation of pancreatic neoplasm by comparing the performance of ¹⁸F-FDG PET/MRI and PET/CT.

PROCEDURES

Patients with suspected pancreatic neoplasms underwent PET/MRI and PET/CT in the same day prior to resection or endoscopic ultrasound-guided fine-needle aspiration. Histology served as the golden standard of lesion classification. Visual assessment on lesion type and lesion malignancy via PET/MRI and PET/CT images was compared. Standard uptake values (SUVs) of PET images from the two scanners were measured and their correlations were further evaluated.

RESULTS

Thirty-nine patients were included for the final analysis. In visual assessment, we found MRI achieved better performance than CT in differentiating solid and cystic neoplasms, with accuracy of 100% vs. 87%, respectively. In visual malignancy diagnosis, the accuracy of PET/CT was 92.3% for overall lesions and 90.9% for cysts, while the accuracy of PET/MRI was 92.3% and 86.4%, respectively. Besides, semi-quantitative analysis achieved better specificity than visual assessment for both hybrid modalities (100% vs. 87.5% for PET/CT; 100% vs. 81.5% for PET/MR). Furthermore, strong correlation of SUV was found between PET/CT and PET/MRI, with Pearson's correlation coefficients > 0.82.

CONCLUSIONS

In this study, we found PET/MRI and PET/CT, both using ¹⁸F-FDG as tracer, had comparable overall performance in identification of pancreatic neoplasms. Interestingly, for patients who had suspected pancreatic neoplasm but invisible FDG uptake, PET/MRI had shown exceptionally better performance, probably because MR images could detect tiny abnormal structures to improve diagnosis.

Pretherapeutic Assessment of Pancreatic Cancer: Comparison of FDG PET/CT Plus Delayed PET/MR and Contrast-Enhanced CT/MR

PURPOSE

This study aims to determine the diagnostic performance of whole-body FDG PET/CT plus delayed abdomen PET/MR imaging in the pretherapeutic assessment of pancreatic cancer in comparison with that of contrast-enhanced (CE)-CT/MR imaging.

MATERIALS AND METHODS

Forty patients with pancreatic cancer underwent nonenhanced whole-body FDG PET/CT, delayed abdomen PET/MR imaging, and CE-CT/MR imaging. Two nuclear medicine physicians independently reviewed these images and discussed to reach a consensus, determining tumor resectability according to a 5-point scale, N stage (N0 or N positive), and M stage (M0 or M1). With use of clinical-surgical-pathologic findings as the reference standard, diagnostic performances of the two imaging sets were compared by using the McNemar test.

RESULTS

The diagnostic performance of FDG PET/CT plus delayed PET/MR imaging was not significantly different from that of CE-CT/MR imaging in the assessment of tumor resectability [area under the receiver operating characteristic curve: 0.927 vs. 0.925 (p = 0.975)], N stage (accuracy: 80% (16 of 20 patients) vs. 55% (11 of 20 patients), p = 0.125), and M stage (accuracy: 100% (40 of 40 patients) vs. 93% (37 of 40 patients), p = 0.250). Moreover, 14 of 40 patients had liver metastases. The number of liver metastases detected by CE-CT/MR imaging, PET/CT, and PET/MR imaging were 33, 18, and 61, respectively. Compared with CE-CT/MR imaging, PET/MR imaging resulted in additional findings of more liver metastases in 9/14 patients, of which 3 patients were upstaged. Compared with PET/CT, PET/MR imaging resulted in additional findings of more liver metastases in 12/14 patients, of which 6 patients were upstaged.

CONCLUSIONS

Although FDG PET/CT plus delayed PET/MR imaging showed a diagnostic performance similar to that of CE-CT/MR imaging in the pretherapeutic assessment of the resectability and staging of pancreatic tumors, it still has potential as the more efficient and reasonable work-up approach for the additional value of metastatic information provided by delayed PET/MR imaging.

Current trends in the diagnosis of pancreatic cancer

Pancreatic ductal adenocarcinoma (PDAC) is a dreaded malignancy with a dismal 5-year survival rate despite maximal efforts on optimizing treatment strategies. Currently, early detection is considered to be the most effective way to improve survival as radical resection is the only potential cure. PDAC is often divided into four categories based on the extent of disease: resectable, borderline resectable, locally advanced, and metastatic. Unfortunately, the majority of patients are diagnosed with locally advanced or metastatic disease, which renders them ineligible for curative resection. This is mainly due to the lack of or vague symptoms while the disease is still localized, although appropriate utilization and prompt availability of adequate diagnostic tools is also critical given the aggressive nature of the disease. A cost-effective biomarker with high specificity and sensitivity allowing early detection of PDAC without the need for advanced or invasive methods is still not available. This leaves the diagnosis dependent on radiodiagnostic methods or endoscopic ultrasound. Here we summarize the latest epidemiological data, risk factors, clinical manifestation, and current diagnostic trends and implications of PDAC focusing on serum biomarkers and imaging modalities. Additionally, up-to-date management and therapeutic algorithms are outlined.

An Immunohistochemical Evaluation of Tumor-Associated Glycans and Mucins as Targets for Molecular Imaging of Pancreatic Ductal Adenocarcinoma

Simple Summary

Distinguishing pancreatic cancer from healthy tissue before and during surgery can be enhanced by using molecular tracers directed at molecules on tumor cells allowing high-contrast visualization of tumor tissue, eventually improving diagnosis and surgical removal. Albeit sugar molecules and proteins carrying a large amount of sugars-mucins- have gained significant interest as tumor-specific targets, their relative presence on structures surrounding tumor tissues and lymph node metastases is unknown. The current study shows that the presence of several, but not all, investigated sugar molecules and mucins on pancreatic cancer cells is higher compared to surrounding tissues. Moreover, given their abundance on tumor cells in lymph nodes and their absence on normal lymph nodes, all investigated targets are high-potential targets for visualization of lymph node metastases. This study paves the way for the development of molecular tracers against the targets evaluated herein to allow improvement of pancreatic cancer treatment.

Abstract

Targeted molecular imaging may overcome current challenges in the preoperative and intraoperative delineation of pancreatic ductal adenocarcinoma (PDAC). Tumor-associated glycans Le^a/c/x, sdi-Le^a, sLe^a, sLe^x, sTn as well as mucin-1 (MUC1) and mucin-5AC (MU5AC) have gained significant interest as targets for PDAC imaging. To evaluate their PDAC molecular imaging potential, biomarker expression was determined using immunohistochemistry on PDAC, (surrounding) chronic pancreatitis (CP), healthy pancreatic, duodenum, positive (LN⁺) and negative lymph node (LN⁻) tissues, and quantified using a semi-automated digital image analysis workflow. Positive expression on PDAC tissues was found on 83% for Le^a/c/x, 94% for sdi-Le^a, 98% for sLe^a, 90% for sLe^x, 88% for sTn, 96% for MUC1 and 67% for MUC5AC, where all were not affected by the application of neoadjuvant therapy. Compared to PDAC, all biomarkers were significantly lower expressed on CP, healthy pancreatic and duodenal tissues, except for sTn and MUC1, which showed a strong expression on duodenum (sTn tumor:duodenum ratio: 0.6, p < 0.0001) and healthy pancreatic tissues (MUC1 tumor:pancreas ratio: 1.0, p > 0.9999), respectively. All biomarkers are suitable targets for correct identification of LN⁺, as well as the distinction of LN⁺ from LN⁻ tissues. To conclude, this study paves the way for the development and evaluation of Le^a/c/x-, sdi-Le^a-, sLe^a-, sLe^x- and MUC5AC-specific tracers for molecular imaging of PDAC imaging and their subsequent introduction into the clinic.

Neoadjuvant Treatment Strategies in Resectable Pancreatic Cancer

Simple Summary

Only 10–20% of patients with newly diagnosed resectable pancreatic adenocarcinoma have potentially resectable disease. Upfront surgery is the gold standard, but it is rarely curative. After surgical extirpation of tumors, up to 80% of patients will develop cancer recurrence, and the initial relapse is metastatic in 50–70% of these patients. Adjuvant chemotherapy offers the best strategy to date to improve overall survival but faces real challenges; some patients will experience rapid disease progression within 3 months of surgery and patients who do not receive all planned cycles of chemotherapy have unfavourable oncological outcomes. The neoadjuvant approach is therefore logical but requires further investigation. This approach shows favourable trends regarding disease-free survival and overall survival but, in the absence of rigorous published phase III trials, is not validated to date. Here, we intend to provide a comprehensive analysis of the literature to provide direction for future studies.

Abstract

Complete surgical resection is the cornerstone of curative therapy for resectable pancreatic adenocarcinoma. Upfront surgery is the gold standard, but it is rarely curative. Neoadjuvant treatment is a logical option, as it may overcome some of the limitations of adjuvant therapy and has already shown some encouraging results. The main concern regarding neoadjuvant therapy is the risk of disease progression during chemotherapy, meaning the opportunity to undergo the intended curative surgery is missed. We reviewed all recent literature in the following areas: major surveys, retrospective studies, meta-analyses, and randomized trials. We then selected the ongoing trials that we believe are of interest in this field and report here the results of a comprehensive review of the literature. Meta-analyses and randomized trials suggest that neoadjuvant treatment has a positive effect. However, no study to date can be considered practice changing. We considered design, endpoints, inclusion criteria and results of available randomized trials. Neoadjuvant treatment appears to be at least a feasible strategy for patients with resectable pancreatic cancer.

The "K-Sign"-A Novel CT Finding Suggestive before the Appearance of Pancreatic Cancer

Pancreatic invasive ductal adenocarcinoma (PDAC) has a poor prognosis, and the detection of PDAC during the early stage is thought to improve prognosis. In this study, we retrospectively investigated pancreatic morphological abnormalities that lead to the early diagnosis of PDAC with computed tomography (CT) imaging. In total, 41 out of 308 patients diagnosed with pancreatic cancer between 2011 and 2017 in our institution were enrolled. As a control group for the group with pancreatic cancer, 4277 patients without pancreato-biliary diseases were enrolled. We retrospectively reviewed and analyzed the clinical data including patient characteristics, the clinical course and preoperative CT imaging with pancreatic morphological features. Out of 41 patients, 24 patients (58.5%) showed local K-shaped constriction of the pancreatic parenchyma "K-sign" on preoperative CT images. Eight patients (19.5%) showed localized fatty change. Out of 4277 control patients, seven patients (0.16%) showed K-sign. "K-sign" may be used for the early diagnosis of PDAC by CT imaging.

Minimally invasive image-guided therapy of primary and metastatic pancreatic cancer

Pancreatic cancer is a challenging malignancy with limited treatment options and poor life expectancy. The only curative option is surgical resection, but only 15%-20% of patients are resectable at presentation because more than 50% of patients has distant metastasis at diagnosis and the rest of them has locally advanced pancreatic cancer (LAPC). The standard of care first line treatment for LAPC patients is chemotherapy with or without radiation therapy. Recent developments in minimally invasive ablative techniques may add to the treatment armamentarium of LAPC. There are increasing number of studies evaluating these novel ablative techniques, including radiofrequency ablation, microwave ablation, cryoablation and irreversible electroporation. Most studies which included pancreatic tumor ablation, demonstrated improved overall survival in LAPC patients. However, the exact protocols are yet to set up to which stage of the treatment algorithm ablative techniques can be added and in what kind of treatment combinations. Patients with metastatic pancreatic cancer has dismal prognosis with 5-year survival is only 3%. The most common metastatic site is the liver as 90% of pancreatic cancer patients develop liver metastasis. Chemotherapy is the primary treatment option for patients with metastatic pancreatic cancer. However, when the tumor is not responding to chemotherapy or severe drug toxicity develops, locoregional liver-directed therapies can provide an opportunity to control intrahepatic disease progression and improve survival in selected patients. During the last decade new therapeutic options arose with the advancement of minimally invasive technologies to treat pancreatic cancer patients. These new therapies have been a topic of increasing interest due to the severe prognostic implications of locally advanced and metastatic pancreatic cancer and the low comorbid risk of these procedures. This review summarizes new ablative options for patients with LAPC and percutaneous liver-directed therapies for patients with liver-dominant metastatic disease.

Radiomic Features at CT Can Distinguish Pancreatic Cancer from Noncancerous Pancreas

Purpose To identify distinguishing CT radiomic features of pancreatic ductal adenocarcinoma (PDAC) and to investigate whether radiomic analysis with machine learning can distinguish between patients who have PDAC and those who do not. Materials and Methods This retrospective study included contrast material-enhanced CT images in 436 patients with PDAC and 479 healthy controls from 2012 to 2018 from Taiwan that were randomly divided for training and testing. Another 100 patients with PDAC (enriched for small PDACs) and 100 controls from Taiwan were identified for testing (from 2004 to 2011). An additional 182 patients with PDAC and 82 healthy controls from the United States were randomly divided for training and testing. Images were processed into patches. An XGBoost (https://xgboost.ai/) model was trained to classify patches as cancerous or noncancerous. Patients were classified as either having or not having PDAC on the basis of the proportion of patches classified as cancerous. For both patch-based and patient-based classification, the models were characterized as either a local model (trained on Taiwanese data only) or a generalized model (trained on both Taiwanese and U.S. data). Sensitivity, specificity, and accuracy were calculated for patch- and patient-based analysis for the models. Results The median tumor size was 2.8 cm (interquartile range, 2.0-4.0 cm) in the 536 Taiwanese patients with PDAC (mean age, 65 years ± 12 [standard deviation]; 289 men). Compared with normal pancreas, PDACs had lower values for radiomic features reflecting intensity and higher values for radiomic features reflecting heterogeneity. The performance metrics for the developed generalized model when tested on the Taiwanese and U.S. test data sets, respectively, were as follows: sensitivity, 94.7% (177 of 187) and 80.6% (29 of 36); specificity, 95.4% (187 of 196) and 100% (16 of 16); accuracy, 95.0% (364 of 383) and 86.5% (45 of 52); and area under the curve, 0.98 and 0.91. Conclusion Radiomic analysis with machine learning enabled accurate detection of PDAC at CT and could identify patients with PDAC. Keywords: CT, Computer Aided Diagnosis (CAD), Pancreas, Computer Applications-Detection/Diagnosis Supplemental material is available for this article. © RSNA, 2021.

How to approach pancreatic cancer after neoadjuvant treatment: assessment of resectability using multidetector CT and tumor markers

OBJECTIVES

To investigate clinical and CT factors associated with local resectability in patients with nonmetastatic pancreatic cancers after neoadjuvant chemotherapy ± radiation therapy (CRT).

METHODS

This retrospective study included consecutive patients with nonmetastatic pancreatic cancers who underwent neoadjuvant CRT between June 2009 and June 2019. Tumor size, tumor-vascular contact with artery/vein, and local resectability categories (resectable, borderline resectable, or locally advanced) were assessed at baseline and post-CRT CT. Baseline and post-CRT carbohydrate antigen (CA) 19-9 levels were also assessed. Clinical or imaging features related to R0 resection were determined using logistic regression analysis.

RESULTS

A total of 179 patients (mean age, 62.4 ± 9.3 years; 92 men) were included. After neoadjuvant CRT, 105 (58.7%) patients received R0 resection, while 74 (41.3%) did not. R0 resection rates were significantly different according to post-CRT CT resectability categories (p < 0.001): 82.8% (48/58), 70.1% (47/67), and 18.5% (10/54) for resectable, borderline resectable, and locally advanced disease, respectively. For post-CRT borderline resectable disease, ≥ 50% decrease in CA 19-9 was significantly associated with R0 resection (odds ratio (OR), 3.160; p = 0.02). For post-CRT locally advanced disease, small post-CRT tumor size ≤ 2 cm (OR, 9.668; p = 0.026) and decreased tumor-arterial contact (OR, 24.213; p = 0.022) were significantly associated with R0 resection.

CONCLUSION

Post-CRT CT resectability categorization may be useful for the assessment of R0 resectability in patients with pancreatic cancer following neoadjuvant CRT. Additionally, ≥ 50% decrease in CA 19-9 was associated with R0 resection in post-CRT borderline resectable disease, while small post-CRT tumor size and decreased tumor-arterial contact were with locally advanced disease.

KEY POINTS

• R0 resection rates following neoadjuvant chemotherapy ± radiation therapy (CRT) were 82.8%, 70.1%, and 18.5% in resectable, borderline resectable, and locally advanced disease, respectively, at post-CRT CT (p < 0.001). • For post-CRT borderline resectable disease, ≥ 50% decrease in carbohydrate antigen (CA) 19-9 was significantly associated with R0 resection. • For post-CRT locally advanced disease, small post-CRT tumor size ≤ 2 cm and decreased tumor-arterial contact were significantly associated with R0 resection.

Water-filled technique for therapeutic pancreato-biliary EUS in patients with surgically altered anatomy

One of the main challenges encountered by endosonographers is performing diagnostic and interventional pancreato-biliary endoscopic ultrasound (EUS) procedures in the presence of surgically altered upper gastrointestinal anatomy. We describe the water-filled technique (WFT) for EUS examination and treatment of the pancreato-biliary region in patients with surgically altered upper gastrointestinal anatomy. Using the WFT, the scope is advanced up to the gastro-jejunal anastomosis and, after placing the tip of the scope 2 cm beyond it, enlargement of the jejunal lumen is obtained by water instillation of the jejunal loop. An enlargement of more than 1.5 cm allows advancement of the tip of the scope under EUSguidance up to the duodenum, in a retrograde way. The WFT is useful for reaching the ampullary area and performing diagnostic and therapeutic EUS in patients with surgically altered anatomy. The technique is also reproducible and can be easily used by endoscopists who regularly perform EUS.

CT in the prediction of margin-negative resection in pancreatic cancer following neoadjuvant treatment: a systematic review and meta-analysis

OBJECTIVES

We aimed to systematically evaluate the diagnostic accuracy of CT-determined resectability following neoadjuvant treatment for predicting margin-negative resection (R0 resection) in patients with pancreatic ductal adenocarcinoma (PDAC).

METHODS

Original studies with sufficient details to obtain the sensitivity and specificity of CT-determined resectability following neoadjuvant treatment, with a reference on the pathological margin status, were identified in PubMed, EMBASE, and Cochrane databases until February 24, 2020. The identified studies were divided into two groups based on the criteria of R0 resectable tumor (ordinary criterion: resectable PDAC alone; extended criterion: resectable and borderline resectable PDAC). The meta-analytic summary of the sensitivity and specificity for each criterion was estimated separately using a bivariate random-effect model. Summary results of the two criteria were compared using a joint-model bivariate meta-regression.

RESULTS

Of 739 studies initially searched, 6 studies (6 with ordinary criterion and 5 with extended criterion) were included for analysis. The meta-analytic summary of sensitivity and specificity was 45% (95% confidence interval [CI], 19-73%; I² = 88.3%) and 85% (95% CI, 65-94%; I² = 60.5%) for the ordinary criterion, and 81% (95% CI, 71-87%; I² = 0.0%) and 42% (95% CI, 28-57%; I² = 6.2%) for the extended criterion, respectively. The diagnostic accuracy significantly differed between the two criteria (p = 0.02).

CONCLUSIONS

For determining resectability on CT, the ordinary criterion might be highly specific but insensitive for predicting R0 resection, whereas the extended criterion increased sensitivity but would decrease specificity. Further investigations using quantitative parameters may improve the identification of R0 resection.

KEY POINTS

• CT-determined resectability of PDAC after neoadjuvant treatment using the ordinary criterion shows low sensitivity and high specificity in predicting R0 resection. • With the extended criterion, CT-determined resectability shows higher sensitivity but lower specificity than with the ordinary criterion. • CT-determined resectability with both criteria achieved suboptimal diagnostic performances, suggesting that care should be taken while selecting surgical candidates and when determining the surgical extent after neoadjuvant treatment in patients with PDAC.

Tissue acquisition and pancreatic masses: Which needle and which acquisition technique should be used?

Background and study aims  Pancreatic cancer represents the fourth most common cause of cancer-related deaths in Western countries and the need of a low-risk investigation to obtain an accurate histopathological diagnosis has become increasingly pressing. Endoscopic ultrasonography (EUS) with fine-needle aspiration (FNA) is the standard method for obtaining samples from pancreatic masses. In recent years, there has been an increasing need to obtain histological specimens during EUS procedures, rather than cytological ones, to guide oncological treatment options, leading to the so-call "FNB concept." Different needles have been developed for fine-needle biopsy (FNB) in recent years, enabling acquisition of larger specimens on which to perform histological and molecular analyses. The aim of this narrative review was to assess the role of EUS-guided FNA and FNB in patients with pancreatic masses, and to identify which needle and which acquisition technique should be used to improve tissue acquisition.

Oligopeptide Transporter-1 is Associated with Fluorescence Intensity of 5-Aminolevulinic Acid-Based Photodynamic Diagnosis in Pancreatic Cancer Cells

Background

The 5-aminolevulinic acid (ALA)-based photodynamic diagnosis is based on the accumulation of photosensitizing protoporphyrin IX in the tumor after ALA administration. However, the mechanisms connecting exogenous ALA and tumor fluorescence in pancreatic cancer remain unclear. We aimed to elucidate the mechanism underlying the ALA-induced fluorescent.

Methods

Human pancreatic duct epithelial cells (hPDECs) and pancreatic cancer cell lines were used. The expressions of ALA-associated enzymes and membrane transporters in these cell lines were investigated. ALA-induced fluorescence was also investigated.

Results

The expression of oligopeptide transporter-1 (PEPT-1), through which ALA is absorbed, was significantly higher in AsPC-1 cells and lower in MIA PaCa-2 cells than in hPDECs. AsPC-1 cells showed rapid and intense fluorescence after ALA administration, and that was attenuated by PEPT-1 inhibition. ALA-induced fluorescence was not sufficiently strong in MIA PaCa-2 cells to distinguish the cells from hPDECs.

Conclusion

We revealed the association of PEPT-1 with ALA-induced fluorescence. Cancers expressing PEPT-1 could be easily distinguished by this technique from normal cells. These findings help develop novel diagnostic modalities for pancreatic cancer.

Accuracy of various criteria for lymph node staging in ductal adenocarcinoma of the pancreatic head by computed tomography and magnetic resonance imaging

BACKGROUND

Lymph node staging of ductal adenocarcinoma of the pancreatic head (PDAC) by cross-sectional imaging is limited. The aim of this study was to determine the diagnostic accuracy of expanded criteria in nodal staging in PDAC patients.

METHODS

Sixty-six patients with histologically confirmed PDAC that underwent primary surgery were included in this retrospective IRB-approved study. Cross-sectional imaging studies (CT and/or MRI) were evaluated by a radiologist blinded to histopathology. Number and size of lymph nodes were measured (short-axis diameter) and characterized in terms of expanded morphological criteria of border contour (spiculated, lobulated, and indistinct) and texture (homogeneous or inhomogeneous). Sensitivities and specificities were calculated with histopathology as a reference standard.

RESULTS

Forty-eight of 66 patients (80%) had histologically confirmed lymph node metastases (pN+). Sensitivity, specificity, and Youden's Index for the criterion "size" were 44.2%, 82.4%, and 0.27; for "inhomogeneous signal intensity" 25.6%, 94.1%, and 0.20; and for "border contour" 62.7%, 52.9%, and 0.16, respectively. There was a significant association between the number of visible lymph nodes on preoperative CT and lymph node involvement (pN+, p = 0.031).

CONCLUSION

Lymph node staging in PDAC is mainly limited due to low sensitivity for detection of metastatic disease. Using expanded morphological criteria instead of size did not improve regional nodal staging due to sensitivity remaining low. Combining specific criteria yields improved sensitivity with specificity and PPV remaining high.

Artificial intelligence in pancreatic disease

In recent years, the application of artificial intelligence (AI) in radiology has been growing rapidly, fueled by the availability of large datasets, advances in computing power, and newly developed algorithms. Progress in AI applied to medical imaging analyses has transformed these images into quantitative data, termed radiomics. When combined with patients’ clinical data, these models, when developed by machine learning, have the potential to improve diagnostic, prognostic, and predictive accuracy. Currently, limited literature is available on the use of radiomics for pancreatic disease. Here, we will review recent studies in the application of AI in a variety of pancreatic diseases, mainly involving lesion detection, tumor characterization, tumor grading, response, and prognosis evaluation. Finally, we will also discuss the challenges and prospects in the field of radiomics for pancreatic disease.

Imaging diagnosis and staging of pancreatic ductal adenocarcinoma: a comprehensive review

Pancreatic ductal adenocarcinoma (PDAC) has continued to have a poor prognosis for the last few decades in spite of recent advances in different imaging modalities mainly due to difficulty in early diagnosis and aggressive biological behavior. Early PDAC can be missed on CT due to similar attenuation relative to the normal pancreas, small size, or hidden location in the uncinate process. Tumor resectability and its contingency on the vascular invasion most commonly assessed with multi-phasic thin-slice CT is a continuously changing concept, particularly in the era of frequent neoadjuvant therapy. Coexistent celiac artery stenosis may affect the surgical plan in patients undergoing pancreaticoduodenectomy. In this review, we discuss the challenges related to the imaging of PDAC. These include radiological and clinical subtleties of the tumor, evolving imaging criteria for tumor resectability, preoperative diagnosis of accompanying celiac artery stenosis, and post-neoadjuvant therapy imaging. For each category, the key imaging features and potential pitfalls on cross-sectional imaging will be discussed. Also, we will describe the imaging discriminators of potential mimickers of PDAC.

Hereditary and Sporadic Pancreatic Ductal Adenocarcinoma: Current Update on Genetics and Imaging

Pancreatic ductal adenocarcinoma (PDAC) is a genetically heterogeneous, biologically aggressive malignancy with a uniformly poor prognosis. While most pancreatic cancers arise sporadically, a small subset of PDACs develop in patients with hereditary and familial predisposition. Detailed studies of the rare hereditary syndromes have led to identification of specific genetic abnormalities that contribute to malignancy. For example, germline mutations involving BRCA1, BRCA2, PRSS1, and mismatch repair genes predispose patients to PDAC. While patients with Lynch syndrome develop a rare "medullary" variant of adenocarcinoma, intraductal papillary mucinous tumors are observed in patients with McCune-Albright syndrome. It is now well established that PDACs originate via a multistep progression from microscopic and macroscopic precursors due to cumulative genetic abnormalities. Improved knowledge of tumor genetics and oncologic pathways has contributed to a better understanding of tumor biology with attendant implications on diagnosis, management, and prognosis. In this article, the genetic landscape of PDAC and its precursors will be described, the hereditary syndromes that predispose to PDAC will be reviewed, and the current role of imaging in screening and staging assessment, as well as the potential role of molecular tumor-targeted imaging for evaluation of patients with PDAC and its precursors, will be discussed. Keywords: Abdomen/GI, Genetic Defects, Oncology, Pancreas Supplemental material is available for this article. © RSNA, 2020.

Prognostic Predicting Role of Contrast-Enhanced Computed Tomography for Locally Advanced Pancreatic Adenocarcinoma

INTRODUCTION

Contrast-enhanced computed tomography (CECT) imaging is commonly used to assess pancreatic adenocarcinoma (PAC). However, the value of semiquantitative and quantitative assessments of CECT parameters used to predict survival in PAC remains unknown. This study aims to investigate the prognostic role of pretreatment CECT imaging in patients with locally advanced pancreatic adenocarcinoma (LAPAC).

MATERIALS AND METHODS

From June 2013 to May 2017, eighty-six newly diagnosed patients with pathologically and radiologically confirmed LAPAC were retrospectively recruited. All patients were evaluated by CECT and experienced gemcitabine-based chemotherapy. The relationship between overall survival (OS) and clinical factors including age, sex, serum carbohydrate antigen 19-9 value, and CECT findings (including tumour location, tumour volume, peripancreatic involvement, blood vessel involvement, tumour enhanced rate, and distance liver metastasis) was determined using Cox proportional hazard regression models, and a nomogram was constructed for the prediction of 1- and 1.5-year survival rates of patients with LAPAC.

RESULTS

On univariate analysis, patients who had a tumour enhanced rate (TER) less than 80.465% and those who had a TER ≥ 80.465% are with a 3.587-fold increase in OS (p < 0.001). After multivariate Cox regression, a nomogram was established based on a new model containing the predictive variables of high Ca19-9 level, higher clinical stages, larger tumour volume, the presence of peripancreatic involvement, and liver metastases. The model displayed good accuracy in predicting OS with a C-index of 0.614. The calibration plots also showed a good discrimination and calibration of the nomogram between the predicted and observed survival probabilities.

CONCLUSION

Our results showed that TER can be used to predict survival in LAPAC, and we developed a nomogram for determining the prognosis of patients with LAPAC. However, the purposed nomogram still requires external data verification in future applications.

Early Diagnosis And Management Of Malignant Distal Biliary Obstruction: A Review On Current Recommendations And Guidelines

Malignant biliary obstruction is a challenging condition, requiring a multimodal approach for both diagnosis and treatment. Pancreatic adenocarcinoma and cholangiocarcinoma are the leading causes of malignant distal biliary obstruction. Early diagnosis is difficult to establish as biliary obstruction can be the first presentation of the underlying disease, which can already be at an advanced stage. Consequently, the majority of patients (70%) with malignant distal biliary obstruction are unresectable at the time of diagnosis. The association of clinical findings, laboratory tests, imaging, and endoscopic modalities may help in identifying the underlying cause. Novel endoscopic techniques such as cholangioscopy, intraductal ultrasonography, or confocal laser endomicroscopy have been developed with promising results, but are not used in routine clinical practice. As the number of patients with malignant distal biliary obstruction who will undergo curative surgery is limited, endoscopy has a crucial role in palliation, to relieve biliary obstruction. According to the last European guidelines published in the management of biliary obstruction, self-expandable metal stents have a central place in biliary drainage compared to plastic stents. Endoscopic ultrasound has evolved impressively in the last decades. When standard techniques of biliary cannulation by endoscopic retrograde cholangiopancreatography fail, endoscopic ultrasound-guided biliary drainage is a good option compared to percutaneous drainage.

Staging of pancreatic cancer: resectable, borderline resectable, and unresectable disease

Pancreatic ductal adenocarcinoma (PDAC) is a relatively common malignancy that carries an overall poor prognosis, with five-year survival below 10%. Despite ongoing research, surgical resection remains the only potentially curative treatment. Therefore, accurate identification of those patients who would benefit from surgical resection is of paramount importance. High-quality imaging and image interpretation is central to this process. Radiology helps in the determination of whether patients are resectable, borderline resectable, or unresectable and guides treatment planning.

Diagnostic and therapeutic recommendations in pancreatic ductal adenocarcinoma. Recommendations of the Working Group of the Polish Pancreatic Club

These recommendations refer to the current management in pancreatic ductal adenocarcinoma (PDAC), a neoplasia characterised by an aggressive course and extremely poor prognosis. The recommendations regard diagnosis, surgical, adjuvant and palliative treatment, with consideration given to endoscopic and surgical methods. A vast majority of the statements are based on data obtained in clinical studies and experts' recommendations on PDAC management, including the following guidelines: International Association of Pancreatology/European Pancreatic Club (IAP/EPC), American Society of Clinical Oncology (ASCO), European Society for Medical Oncology (ESMO), National Comprehensive Cancer Network (NCCN) and Polish Society of Gastroenterology (PSG) and The National Institute for Health and Care Excellence (NICE). All recommendations were voted on by members of the Working Group of the Polish Pancreatic Club. Results of the voting and brief comments are provided with each recommendation.

Predictors of distant metastasis on exploration in patients with potentially resectable pancreatic cancer

BACKGROUND

Patients with potentially resectable pancreatic ductal adenocarcinoma (PDAC) are frequently found to be unresectable on exploration due to small distant metastasis. This study was to investigate predictors of small distant metastasis in patients with potentially resectable PDAC.

METHODS

Patients who underwent surgical exploration for potentially resectable PDAC from 2013 to 2014 were reviewed retrospectively and divided into two groups according to whether distant metastases were encountered on exploration. Then, univariate and multivariate logistic regression analyses were used to identify predictors of distant metastasis. A scoring system to predict distant metastasis of PDAC on exploration was constructed based on the regression coefficient of a multivariate logistic regression model.

RESULTS

A total of 235 patients were included in this study. Mean age of the study population was 61.7 ± 10.4 years old. Upon exploration, distant metastases were found intraoperatively in 62 (26.4%) patients, while the remaining 173 were free of distant metastases. Multivariate logistic regression analysis identified that age ≤ 62 years old (p < 0.001), male sex (p = 0.011), tumor size ≥4.0 cm (p < 0.001), alanine aminotransferase level (ALT) < 125 U/L (p < 0.001), and carbohydrate antigen (CA19-9) level ≥ 385 U/mL (p < 0.001) were independent risk factors for occult distant metastasis of PDAC. A preoperative scoring system (0-8 points) for distant metastasis on exploration was constructed using these five factors. The receiver operating characteristic curves showed that the area under the curve of this score was 0.85. A score of 6 points was suggested to be the optimal cut-off value, and the sensitivity and specificity were 85% and 69%, respectively.

CONCLUSIONS

Distant metastasis is still frequently encountered on exploration for patients with potentially resectable PDAC. Younger age, male sex, larger tumor size, low ALT level and high CA19-9 level are independent predictors of unexpected distant metastasis on exploration.

Survival of Patients with Oligometastatic Pancreatic Ductal Adenocarcinoma Treated with Combined Modality Treatment Including Surgical Resection: A Pilot Study

Purpose: To evaluate the overall survival of patients with oligometastatic pancreatic ductal adenocarcinoma (PDAC; metastatic tumor <4 cm, ≤2 metastatic tumors total) receiving neoadjuvant therapy, metastasectomy and/or ablation, and primary tumor resection.

Methods: We performed a case–control study from January 2005 to December 2015. Patients who underwent curative-intent surgery combined modality therapy (M1 surgery group; 6 [14%], tumor [T]3, node [N]1, and oligo-metastases [M]1) were matched 1 to 3 based on TN stage with two control groups (M0 surgery and M1 no surgery). The M0 surgery group (18 [43%], T3, N1, and M0) included patients without metastases who underwent resection. The M1 no surgery group (18 [43%], T3, N1, and M1) included patients with metastatic PDAC who received palliative chemotherapy without surgical resection.

Results: Median overall survival in the M1 surgery, M0 surgery, and M1 no surgery groups was 2.7 years (95% confidence interval [CI], 0.71–3.69), 2.02 years (95% CI, 0.98–3.05), and 0.98 years (95% CI, 0.55–1.25), respectively. Eastern Cooperative Oncology Group (ECOG) status was associated with survival (p = 0.01) after univariate analysis. After adjusting for ECOG status, multivariate analysis showed M1 surgery patients had improved survival compared with M1 no surgery patients and similar survival to M0 surgery patients.

Conclusion: Multimodal therapy benefitted our M1 surgery patients. A larger, prospective study of this multidisciplinary management strategy is currently under way.

Borderline resectable pancreatic cancer: conceptual evolution and current approach to image-based classification

Background

Diagnostic imaging plays a critical role in the initial diagnosis and therapeutic monitoring of pancreatic adenocarcinoma. Over the past decade, the concept of 'borderline resectable' pancreatic cancer has emerged to describe a distinct subset of patients existing along the spectrum from resectable to locally advanced disease for whom a microscopically margin-positive (R1) resection is considered relatively more likely, primarily due to the relationship of the primary tumor with surrounding vasculature.

Materials and methods

This review traces the conceptual evolution of borderline resectability from a radiological perspective, including the debates over the key imaging criteria that define the thresholds between resectable, borderline resectable, and locally advanced or metastatic disease. This review also addresses the data supporting neoadjuvant therapy in this population and discusses current imaging practices before and during treatment.

Results

A growing body of evidence suggests that the borderline resectable group of patients may particularly benefit from neoadjuvant therapy to increase the likelihood of an ultimately margin-negative (R0) resection. Unfortunately, anatomic and imaging criteria to define borderline resectability are not yet universally agreed upon, with several classification systems proposed in the literature and considerable variance in institution-by-institution practice. As a result of this lack of consensus, as well as overall small patient numbers and lack of established clinical trials dedicated to borderline resectable patients, accurate evidence-based diagnostic categorization and treatment selection for this subset of patients remains a significant challenge.

Conclusions

Clinicians and radiologists alike should be cognizant of evolving imaging criteria for borderline resectability given their profound implications for treatment strategy, follow-up recommendations, and prognosis.

Photodynamic diagnosis of peritoneal metastasis in human pancreatic cancer using 5-aminolevulinic acid during staging laparoscopy

Peritoneal metastasis is an important prognostic factor for pancreatic cancer. The present study evaluated the possibility of diagnosing peritoneal metastasis by a photodynamic diagnosis using 5-aminolevulinic acid (5-ALA-PDD). In vitro, protoporphyrin IX (PpIX) accumulation was examined in the AsPC-1-GFP cell line following 5-ALA hydrochloride administration. In vivo, AsPC-1-GFP cells were injected into the peritoneal cavities of mice. Three weeks later 5-ALA hydrochloride was intraperitoneally administered to the mice. The peritoneal nodules were observed under fluorescence excitation. A total of 34 patients were enrolled in the present study who were clinically diagnosed with pancreatic malignancy. 5-ALA hydrochloride was orally administered to the patients prior to surgery. During the operation the abdominal cavity was observed under white light and fluorescence. In vitro and in vivo, it was confirmed that PpIX-induced red fluorescence. In 9 patients peritoneal nodules suspected to be peritoneal metastasis were observed under white light. In 4 of the 9 patients nodules were detected on the basis of the fluorescence images. Fluorescent nodules were histopathologically diagnosed as metastatic. In the present study it was confirmed that 5-ALA-PDD holds promise for the rapid diagnosis of peritoneal metastasis in patients with pancreatic cancer.

Advanced EUS Guided Tissue Acquisition Methods for Pancreatic Cancer

Pancreas cancer is a lethal cancer as the majority patients are diagnosed at an advanced incurable stage. Despite improvements in diagnostic modalities and management strategies, including surgery and chemotherapies, the outcome of pancreas cancer remains poor. Endoscopic ultrasound (EUS) is an important imaging tool for pancreas cancer. For decades, resected pancreas cancer and other cancer specimens have been used to identify tissue biomarkers or genomics for precision therapy; however, only 20% of patients undergo surgery, and thus, this framework is not useful for unresectable pancreas cancer. With advancements in needle technologies, tumor specimens can be obtained at the time of tissue diagnosis. Tumor tissue can be used for development of personalized cancer treatment, such as performing whole exome sequencing and global genomic profiling of pancreas cancer, development of tissue biomarkers, and targeted mutational assays for precise chemotherapy treatment. In this review, we discuss the recent advances in tissue acquisition of pancreas cancer.

Evaluation of 22G fine-needle aspiration (FNA) versus fine-needle biopsy (FNB) for endoscopic ultrasound-guided sampling of pancreatic lesions: a prospective comparison study

Background

To compare the diagnostic yield and safety of 22G endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) and endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) in the diagnosis of pancreatic solid lesions.

Methods

Between April 2014 and September 2015, 36 patients with pancreatic solid lesions were included for endoscopic ultrasound test. Patients were randomly divided into two groups: EUS-FNA (n = 18) and EUS-FNB (n = 18). Each nidus was punctured three times (15 ~ 20 insertions for each puncture) with a 22G needle. The core specimens were analyzed, and the diagnostic yields of FNA and FNB were evaluated.

Results

The procedure success rate was 100% with no complications. Cytological and histological examinations found that the diagnostic yield of FNB and FNA were both 83.3%. To get a definitive diagnosis, FNB needed fewer punctures than FNA (1.11 vs. 1.83; P  <  0.05).

Conclusions

22G EUS-FNB is a safe and effective way to diagnose pancreatic solid lesions. FNB required a lower number of needle passes to achieve a diagnosis compared with FNA.

Present status and perspectives of endosonography 2017 in gastroenterology

Endoscopic ultrasound has become an essential tool in modern gastroenterology and abdominal surgery. Compared with all other endoscopic methods, it has the most potential for innovation and its future looks bright. Thus, we compiled this summary of established and novel applications of endoscopic ultrasound methods to inform the reader about what is already possible and where future developments will lead in improving patient care further. This review is structured in four parts. The first section reports on developments in diagnostic endoscopic ultrasound, the second looks at semi-invasive endoscopic ultrasound, and the third discusses advances in therapeutic endoscopic ultrasound. An overview on the future prospects of endoscopic ultrasound methods concludes this article.

Incremental Role of Fluorine 18-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography in the Assessment of Computed Tomography-Inconspicuous Pancreatic Lesions

Background: Pancreatic malignancies encompass a heterogenous group of disorders, with poor prognosis at diagnosis. Traditionally, conventional computed tomography (CT) has been used for diagnosis, staging, and follow up. However, this technique lacks functional information; and is limited in diagnosis of occult pancreatic disease. Hybrid imaging in the form of positron emission tomography (PET)/CT provides a potential avenue for early detection and subsequent appropriate therapy.

Case Presentation: A 60-year-old male, with a history of abdominal aortic aneurysm which was repaired, came with a complaint of 2 months history of back pain, radiating to the front. The pain was relieved on leaning forward, and aggravated by lying on his back. CT angiography of the abdomen was done, which revealed a concealed aortic aneurysm and a significant atrophy of the pancreatic tail. The serum cancer antigen (CA) 19-9 was elevated (50.0 U/mL, reference range 0.0–37.0 U/mL). At this juncture, the PET scan done revealed no discernible abnormalities. Patient was put on close follow-up in view of the rising trend of CA 19-9 levels. Three months following the initial scans, a repeat ¹⁸F-FDG (fluorine 18 fluorodeoxyglucose) PET/CT revealed an FDG-avid lesion at the neck of the pancreas on PET without perceptible changes on the correlated CT. A Whipple's procedure ensued, with histopathological examination findings of pancreatic adenocarcinoma.

Conclusion: This article discusses the role of PET/CT in the early diagnosis of inconspicuous pancreatic lesions; which could have averted immediate medical therapy.

Comparison of DWIBS/T2 image fusion and PET/CT for the diagnosis of cancer in the abdominal cavity

Fusion images of diffusion-weighted whole-body imaging with background body signal suppression and T2-weighted image (DWIBS/T2) demonstrate a strong signal for malignancies, with a high contrast against the surrounding tissues, and enable anatomical analysis. In the present study, DWIBS/T2 was compared with ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography/computed tomography (PET/CT) for diagnosing cancer in the abdomen. Patient records, including imaging results of examination conducted between November 2012 and May 2014, were analyzed retrospectively. In total, 10 men (age, 73.6±9.6 years) and 8 women (age, 68.9±7.1 years) were enrolled into the current study. Of the enrolled patients, 2 were diagnosed with hepatocellular carcinoma, 1 with cholangiocellular carcinoma, 1 with liver metastasis, 2 with pancreatic ductal adenocarcinoma, 1 with renal cell carcinoma and 1 with malignant lymphoma. Benign lesions were also analyzed, including adenomyomatosis of the gallbladder (5 patients), intraductal papillary mucinous neoplasm (4 patients) and right adrenal adenoma (1 case). All the patients with cancer showed positive results on DWIBS/T2 images. However, only 7 out of 8 patients were positive with PET/CT. One patient with right renal cellular carcinoma was positive with DWIBS/T2, but negative with PET/CT. All the patients with benign lesions were negative with DWIBS/T2 and PET/CT. In conclusion, DWIBS/T2 was more sensitive in diagnosing cancer of organs in the abdominal cavity compared with PET/CT. Furthermore, negative results with DWIBS/T2 and PET/CT were useful for the diagnosis of benign lesions, such as adenomyomatosis of the gallbladder and intraductal papillary mucinous neoplasm.

Adjuvant treatment for pancreatic ductal carcinoma

Pancreatic ductal adenocarcinoma (PDAC) is a tumor with a very poor prognosis. Most of the patients are diagnosed in advanced stages of the disease, and 5-year survival rates in these patients remains <10%. Surgery still remains the only radical treatment option, although only 15-20% of patients are candidates for surgical resection at the time of the diagnosis. Patients who undergo radical surgery still have a limited survival rate, being the average of 23 months. Three clinical trials have shown that adjuvant chemotherapy therapy after surgery may improve survival: CONKO-1, ESPAC-3, and ESPAC-4. Adjuvant therapy is recommended in patients with R0/R1, T1-4/N1-0 tumors and with ECOG 0-1. In patients with ECOG-2, the decision needs to be individualized. Treatment schemes that have demonstrated efficacy include gemcitabine alone, 5-fluorouracil, or the combination of gemcitabine and capecitabine for six months. Prior to adjuvant treatment, the following test are recommended: Complete blood tests, including CA19.9 biomarker; imaging studies to rule out early disease relapse (preferable thorax-abdomen-pelvic CT). Studies that have evaluated the efficacy of radiation therapy in the adjuvant setting have presented conflicting results. Its use should be considered in patients with R1 or R2 tumors or in those with lymph nodes involved.

Review of radiological classifications of pancreatic cancer with peripancreatic vessel invasion: are new grading criteria required?

Pancreatic cancer is mainly diagnosed at an advanced stage when adjacent vessel invasion is present; however, radical resection is potentially curative for selected patients with adjacent vessel invasion. Therefore, accurately judging the resectability of patients with adjacent vessel invasion represents a crucially important step in diagnosis and treatment. Currently, decisions regarding resectability are based on imaging studies, commonly contrast computed tomography (CT). Several radiological classifications have been published for vascular infiltration in pancreatic cancer. However, radiologists always formulate these CT grading systems according to their own experience, resulting in different judgment methods and parameters. And it is controversial in evaluating performance and clinical application. Besides, the conventional CT grading systems mainly focus on the evaluation of vessel invasion so as to less on the outcome of patient evaluation. In this review, we summarize the mainstream CT grading systems for vascular invasion in pancreatic cancer, with the aim of improving the clinical value of CT grading systems for predicting resectability and survival.

Opportunities for new CT contrast agents to maximize the diagnostic potential of emerging spectral CT technologies

The introduction of spectral CT imaging in the form of fast clinical dual-energy CT enabled contrast material to be differentiated from other radiodense materials, improved lesion detection in contrast-enhanced scans, and changed the way that existing iodine and barium contrast materials are used in clinical practice. More profoundly, spectral CT can differentiate between individual contrast materials that have different reporter elements such that high-resolution CT imaging of multiple contrast agents can be obtained in a single pass of the CT scanner. These spectral CT capabilities would be even more impactful with the development of contrast materials designed to complement the existing clinical iodine- and barium-based agents. New biocompatible high-atomic number contrast materials with different biodistribution and X-ray attenuation properties than existing agents will expand the diagnostic power of spectral CT imaging without penalties in radiation dose or scan time.

Imaging in pancreatic disease

Pancreatic diseases, chronic pancreatitis, pancreatic cancer and diabetes mellitus, taken together, occur in >10% of the world population. Pancreatic diseases, as with other diseases, benefit from early intervention and appropriate diagnosis. Although imaging technologies have given clinicians an unprecedented toolbox to aid in clinical decision-making, advances in these technologies and development of molecular-based diagnostic tools could enable physicians to identify diseases at an even earlier stage and, thereby, improve patient outcomes. In this Review, we discuss and identify gaps in the use of imaging techniques for the early detection and appropriate treatment stratification of various pancreatic diseases, including diabetes mellitus, acute and chronic pancreatitis and pancreatic cancer. Imaging techniques discussed are MRI, CT, PET and ultrasonography. Additionally, the identification of new molecular targets for imaging and the development of contrast agents that are able to give molecular information in noninvasive radionuclear imaging and ultrasonography are emerging areas of innovation that could lead to increased diagnostic accuracy and improved patient outcomes.

Procedures and recommended times in the care process of the patient with pancreatic cancer: PAN-TIME consensus between scientific societies

PURPOSE

Pancreatic cancer (PC) is a disease with bad prognosis. It is usually diagnosed at advanced stages and its treatment is complex. The aim of this consensus document was to provide recommendations by experts that would ameliorate PC diagnosis, reduce the time to treatment, and optimize PC management by interdisciplinary teams.

METHODS

As a consensus method, we followed the modified Delphi methodology. A scientific committee of experts provided 40 statements that were submitted in two rounds to a panel of 87 specialists of 12 scientific societies.

RESULTS

Agreement was reached for 39 of the 40 proposed statements (97.5%).

CONCLUSIONS

Although a screening of the asymptomatic population is not a feasible option, special attention to potential symptoms during primary care could ameliorate early diagnostic. It is especially important to decrease the period until diagnostic tests are performed. This consensus could improve survival in PC patients by decreasing the time to diagnose and time to treatment and by the implementation of multidisciplinary teams.

Current and Emerging Clinical Applications of Multispectral Optoacoustic Tomography (MSOT) in Oncology

Accurate detection and characterization of cancers are key for providing timely intervention and effective treatments. Current imaging technologies are particularly limited when it comes to detecting very small tumors in vivo, i.e., very early cancers or metastases, differentiating viable tumor from surrounding dead tumor tissue, and evaluating tumor metabolism within tissue. Optoacoustic imaging offers potential solutions to these imaging problems because of its ability to image optical absorption properties of both intrinsic tissue chromophores and exogenous contrast agents without the involvement of ionizing radiation. Optoacoustic imaging uses pulsed laser to induce localized thermoelastic expansion that generates acoustic waves detectable by an ultrasound transducer. To date, multispectral optoacoustic tomography (MSOT) has primarily been used in preclinical research; however, its use in translational and clinical research is expanding. This review focuses on current and emerging applications of optoacoustic imaging for molecular imaging of cancer using both exogenous and endogenous contrast agents and sheds light on potential future clinical applications. Clin Cancer Res; 22(14); 3432-9. ©2016 AACR.

Systematic Review of Resection Rates and Clinical Outcomes After FOLFIRINOX-Based Treatment in Patients with Locally Advanced Pancreatic Cancer

Background

FOLFIRINOX prolongs survival in patients with metastatic pancreatic cancer and may also benefit patients with locally advanced pancreatic cancer (LAPC). Furthermore, it may downstage a proportion of LAPC into (borderline) resectable disease, however data are lacking. This review assessed outcomes after FOLFIRINOX-based therapy in LAPC.

Methods

The PubMed, EMBASE and Cochrane library databases were systematically searched for studies published to 31 August 2015. Primary outcome was the (R0) resection rate.

Results

Fourteen studies involving 365 patients with LAPC were included; three studies administered a modified FOLFIRINOX regimen. Of all patients, 57 % (n = 208) received radiotherapy. The pooled resection rate was 28 % (n = 103, 77 % R0), with a perioperative mortality of 3 % (n = 2), and median overall survival ranged from 8.9 to 25.0 months. Survival data after resection were scarce, with only one study reporting a median overall survival of 24.9 months in 28 patients. A complete pathologic response was found in 6 of 85 (7 %) resected specimens. Dose reductions were described in up to 65 % of patients, grade 3–4 toxicity occurred in 23 % (n = 51) of patients, and 2 % (n = 5) had to discontinue treatment. Data of patients treated solely with FOLFIRINOX, without additional radiotherapy, were available from 292 patients: resection rate was 12 % (n = 29, 70 % R0), with 15.7 months median overall survival and 19 % (n = 34) grade 3–4 toxicity.

Conclusions

Outcomes after FOLFIRINOX-based therapy in patients with LAPC seem very promising but further prospective studies are needed, especially with regard to survival after resection.

Pancreatic Cancer from Molecular Pathways to Treatment Opinion

Pancreatic cancer is considered one of the most lethal malignances. It has been observed that the five year survival rate is less than 5%. Early diagnosis, understanding the risk factors and investigation of the molecular pathways with targeted therapy are the keys for efficient treatment. Moreover; there are several local treatments for patients with unresectable pancreatic cancer. There are several combined therapies with chemotherapy and radiotherapy, however; a local therapy approach for many patients with poor performance status are in need. For those patients with good performance status new polychemotherapy regimens are used with success and increased survival improvement. Polychemotherapy has been observed to increase the rate of radical resections in some cases. Second line therapy is used for patients with good performance status and metastatic disease. Oxaliplatin-based regimens are mostly used, however; there are several other drugs that are being developed. Unfortunately, targeted therapy has not presented the expected efficiency. Moreover; immunotherapy; another treatment approach for several cancers types has again failed to present positive results for pancreatic cancer. In the current mini review, we will present information from the diagnosis to molecular pathways and targeted treatment.

Absence of a Periampullary Mass on Cross-sectional Imaging Delays Diagnosis and Time to Pancreatoduodenectomy But Does Not Impair Outcome

BACKGROUND

The aim of this study was to assess whether the lack of a radiological mass in patients with periampullary malignancies led to protracted diagnosis, delayed resection, and an inferior outcome.

METHODS

The departmental database was interrogated to identify all patients undergoing pancreatoduodenectomy during the period 2000-2014. The absence of a mass on cross-sectional and endoscopic ultrasound was noted. The interval between imaging and surgery was evaluated and related to the absence of a mass. The relationship between mass/no mass and the pathological profile was also assessed.

RESULTS

Among 490 patients who underwent pancreatoduodenectomy for periampullary malignancies, masses were detected in 299 patients. Patients with undetected mass on either endoscopic ultrasonography (EUS) or computed tomography (CT)/magnetic resonance imaging (MRI) had a longer median interval from initial imaging to resection than detected mass with no difference in survival (66 vs. 41 days, p = 0.001). The absence of a mass was more common in cholangiocarcinomas (p < 0.001). The absence of a mass on imaging was associated with smaller size on final histopathology (2.4 vs. 2.8 cm; p < 0.001).

CONCLUSIONS

The absence of a mass with all modalities in patients with a periampullary malignancy leads to a delayed diagnosis without a significant effect on survival.

[Ductal adenocarcinoma and unusual differential diagnosis]

Ductal pancreatic adenocarcinoma is by far the most common solid tumor of the pancreas. It has a very poor prognosis, especially in the more advanced stages which are no longer locally confined. Due to mostly unspecific symptoms, imaging is key in the diagnostic process. Because of the widespread use of imaging techniques, incidental findings are to a greater extent discovered in the pancreas, which subsequently entail further work-up. Ductal pancreatic adenocarcinoma can be mimicked by a large number of different lesions, such as anatomical variants, peripancreatic structures and tumors, rarer primary solid pancreatic tumors, cystic tumors, metastases or different variants of pancreatitis. Additionally, a number of precursor lesions can be differentiated. The correct classification is thus important as an early diagnosis of ductal pancreatic adenocarcinoma is relevant for the prognosis and because the possibly avoidable treatment is very invasive. All major imaging techniques are principally suitable for pancreatic imaging. In addition to sonography of the abdomen, usually the baseline diagnostic tool, computed tomography (CT) with its superior spatial resolution, magnetic resonance imaging (MRI) with its good soft tissue differentiation capabilities, possibly in combination with MR cholangiopancreatography (MRCP), endosonography with its extraordinary spatial resolution, conceivably with additional endoscopic retrograde CP or the option of direct biopsy and finally positron emission tomography CT (PET-CT) as a molecular imaging tool are all particularly useful modalities. The various techniques all have its advantages and disadvantages; depending on the individual situation they may need to be combined.

The role of contrast-enhanced endoscopic ultrasound in pancreatic adenocarcinoma

Contrast-enhanced endoscopic ultrasound (CE-EUS) allows characterization, differentiation, and staging of focal pancreatic masses. The method has a high sensitivity and specificity for the diagnosis of pancreatic adenocarcinoma which is visualized as hypo-enhanced as compared to the rest of the parenchyma while chronic pancreatitis and neuroendocrine tumors are generally either iso-enhanced or hyper-enhanced. The development of contrast-enhanced low mechanical index harmonic imaging techniques used in real time during endoscopic ultrasound (EUS) allowed perfusion imaging and the quantification of intensity of the contrast signal through time-intensity curve analysis. Thus, contrast harmonic imaging-EUS has been used to differentiate pancreatic adenocarcinoma based on lower values of the peak enhancement. Future applications of CE-EUS in pancreatic adenocarcinoma include not only use of targeted contrast agents for early detection, tridimensional and fusion techniques for enhanced staging and resectability assessment but also novel applications of perfusion imaging for monitoring ablative therapy, improved local detection through EUS-guided sampling of portal vein flow or enhanced drug delivery through sonoporation and ultrasound-induced release of the drugs locally.