Pancreatic cancer: an endoscopic perspective

The role of seed implantation in patients with unresectable pancreatic carcinoma after relief of obstructive jaundice using ERCP

PURPOSE

The purpose of the study was to investigate the role of iodine-125 seed implantation, guided by endoscopic ultrasound (EUS) and/or percutanous ultrasound, in patients with unresectable pancreatic carcinoma after relief of obstructive jaundice using endoscopic retrograde cholangiopancreatography (ERCP).

METHODS AND MATERIALS

A total of 101 patients with obstructive jaundice due to unresectable pancreatic carcinoma were enrolled between January 2010 and December 2017 in this retrospective study. Of these patients, 50 underwent implantation of iodine-125 seeds under EUS and/or percutaneous ultrasound guidance after receiving a stent via ERCP (treatment group), and 51 received a stent via ERCP without undergoing seed implantation (control group). The clinical data and therapeutic outcomes of these patients were analyzed.

RESULTS

Compared with the control group, the treatment group obtained significant relief of abdominal pain at the 1-week, 1-month, and 3-month followup (p < 0.05), with a significantly lower visual analog scale pain score (p < 0.05). The treatment group obtained a longer median survival (8.8 vs. 6.5 months, p = 0.02), longer median duration of stent patency (10.8 ± 1.4 vs. 6.9 ± 0.8 months, p = 0.02), and prolonged average time to gastric outlet obstruction (6.8 ± 1.6 vs. 5.3 ± 1.3 months, p = 0.02). Differences between liver function and appetite for the two groups were not significant (p > 0.05 and p = 0.59, respectively).

CONCLUSIONS

Iodine-125 seed implantation after relief of obstructive jaundice via ERCP prolongs survival, biliary stent patency, and time to gastric outlet obstruction and improves patient quality of life by relieving pancreatic pain in patients with unresectable pancreatic carcinoma.

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.

The clinical utility of image-guided iodine-125 seed in patients with unresectable pancreatic cancer

In the present study, we investigated the clinical effects of image-guided iodine-125 ((125)I) seed on unresectable pancreatic cancer. Twenty-five patients with unresectable pancreatic cancer were enrolled in this study, including 13 patients with seed implantation and 12 patients as control. The survival status, clinical benefits, objective curative effects, and relevant tumor markers were analyzed to assess the feasibility and safety of interstitial (125)I seed implantation. We found that the clinical benefit rate of the seed implantation group is 92.3 % (12/13), compared with 41.7 % (5/12) in the control, and the difference was statistically significant (p < 0.01). Compared with control, patients with seed implantation had significantly shorter operative time, less bleeding, higher albumin, shorter periods to bowel movement, and normal diet as well as lower risk of complications (p < 0.001). The differences of objective curative effects adverse effects, complications, and median survival between these two groups were not significant statistically (p > 0.05). In conclusion, (125)I seed implantation provides a safe and effective method to inhibit the tumor development, relieve pain, and improve quality of life for unresectable pancreatic cancer. These findings need to be validated by conducting further studies with larger cohorts.

Endoscopic ultrasonography for tumor node staging and vascular invasion in pancreatic cancer: a meta-analysis

BACKGROUND/AIMS

The accurate staging of pancreatic cancer (PanCa) is crucial in the development of a stage-specific treatment plan for PanCa patients. We aimed to perform a meta-analysis of endoscopic ultrasonography (EUS) in the tumor node (TN) staging and evaluation of vascular invasion in PanCa.

METHODS

A meta-analysis of diagnostic accuracy parameters was performed to evaluate the EUS-based TN staging, and vascular invasion by PanCa was compared to the results of intraoperative staging or to the histopathology of resected specimens.

RESULTS

Twenty studies with 726 PanCa cases were identified from 281 articles. The pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), and diagnostic odds ratio (DOR) were 0.72, 0.90, 6.27, 0.28, and 24.69, respectively, for T1-2 staging and 0.90, 0.72, 3.58, 0.16, and 24.69, respectively, for T3-4 staging. The overall sensitivity, specificity, PLR, NLR, and DOR were 0.62, 0.74, 2.54, 0.51, and 6.67, respectively, for N staging (positive vs. negative) and 0.87, 0.92, 7.16, 0.20, and 56.19, respectively, for vascular invasion. The area under the curve was 0.90, 0.90, 0.79, and 0.94 for T1-2 staging, T3-4 staging, N staging, and vascular invasion, respectively.

CONCLUSIONS

EUS is a reliable and accurate diagnostic tool for the TN staging and evaluation of vascular invasion in PanCa. The nodal staging accuracy using EUS is less satisfactory.

Vascular endothelial growth factor receptor type 2-targeted contrast-enhanced US of pancreatic cancer neovasculature in a genetically engineered mouse model: potential for earlier detection

PURPOSE

To test ultrasonographic (US) imaging with vascular endothelial growth factor receptor type 2 (VEGFR2)-targeted microbubble contrast material for the detection of pancreatic ductal adenocarcinoma (PDAC) in a transgenic mouse model of pancreatic cancer development.

MATERIALS AND METHODS

Experiments involving animals were approved by the Institutional Administrative Panel on Laboratory Animal Care at Stanford University. Transgenic mice (n = 44; Pdx1-Cre, KRas(G12D), Ink4a(-/-)) that spontaneously develop PDAC starting at 4 weeks of age were imaged by using a dedicated small-animal US system after intravenous injection of 5 × 10(7) clinical-grade VEGFR2-targeted microbubble contrast material. The pancreata in wild-type (WT) mice (n = 64) were scanned as controls. Pancreatic tissue was analyzed ex vivo by means of histologic examination (with hematoxylin-eosin staining) and immunostaining of vascular endothelial cell marker CD31 and VEGFR2. The Wilcoxon rank sum test and linear mixed-effects model were used for statistical analysis.

RESULTS

VEGFR2-targeted US of PDAC showed significantly higher signal intensities (26.8-fold higher; mean intensity ± standard deviation, 6.7 linear arbitrary units [lau] ± 8.5; P < .001) in transgenic mice compared with normal, control pancreata of WT mice (mean intensity, 0.25 lau ± 0.25). The highest VEGFR2-targeted US signal intensities were observed in smaller tumors, less than 3 mm in diameter (30.8-fold higher than control tissue with mean intensity of 7.7 lau ± 9.3 [P < .001]; and 1.7-fold higher than lesions larger than 3 mm in diameter with mean intensity of 4.6 lau ± 5.8 [P < .024]). Ex vivo quantitative VEGFR2 immunofluorescence demonstrated that VEGFR2 expression was significantly higher in pancreatic tumors (P < .001; mean fluorescent intensity, 499.4 arbitrary units [au] ± 179.1) compared with normal pancreas (mean fluorescent intensity, 232.9 au ± 83.7).

CONCLUSION

US with clinical-grade VEGFR2-targeted microbubbles allows detection of small foci of PDAC in transgenic mice.

Comparison of iodine-125 seed implantation and pancreaticoduodenectomy in the treatment of pancreatic cancer

OBJECTIVE

This retrospective study compared the advantages and disadvantages of iodine-125 (125I) seed implantation and pancreaticoduodenectomy (PD) in the treatment of pancreatic cancer.

METHODS

Patients with diagnosed pancreatic cancer who were treated with 125125I seed implantation (30 patients) or PD (30 patients) in our hospital were evaluated for operative time, bleeding, liver function, time to first bowel movement and normal diet, survival, and medical costs.

RESULTS

Compared with patients who underwent PD, those given 125I seed implantation had significantly shorter operative time, less bleeding, higher albumin, shorter periods to bowel movement and normal diet, lower risk of complications, and lower medical costs (P < 0.001, each). The difference of bilirubin level, time to feeding, and median survival were not significant statistically between two treatment grouops.

CONCLUSION

For pancreatic cancer patients for whom PD is not appropriate or who refuse PD, 125I seed implantation is a good option.