The surgical management of pancreatic cancer

Modern ultrasound imaging of pancreatic tumors

In patients with solid pancreatic lesions (SPLs), the differential diagnosis must be evaluated to determine whether radical surgery, pancreatic parenchyma-saving strategies, or follow-up is indicated. Contrast-enhanced (endoscopic) ultrasonography and elastography facilitate the further characterization of SPLs. The majority of cases of pancreatic ductal adenocarcinoma exhibit hypoenhancement with contrast-enhanced ultrasonography. Elastographically soft SPLs are benign with very few exceptions, whereas stiffer SPLs can be malignant or benign. This article reviews the current use of modern ultrasound imaging techniques, including contrast-enhanced ultrasonography and elastography, for the detection and characterization of SPLs. In particular, the unexcelled diagnostic potential of multiparametric endoscopic ultrasonography to detect and characterize small SPLs is highlighted.

Low dose photodynamic therapy harmonizes with radiation therapy to induce beneficial effects on pancreatic heterocellular spheroids

Photodynamic therapy (PDT) has seen long standing interest as a therapy for resistant cancers, but the main Achilles’ heel for its successful clinical exploitation is the use of poorly penetrating visible light. This limitation could be overcome by using radioluminescent nanoparticles, which can be excited during radiation therapy (RT) with penetrating X-rays. When infused in tumors, X-ray activated-nanoscintillators act as internal light sources and excite nearby photosensitizers. Recent studies demonstrated that it is realistic to achieve low dose PDT with current nanoscintillators. However, as the origin of enhanced RT efficacy with nanoscintillators may have varying origins, we aimed to answer the basic question: Is a combination of low-dose PDT beneficial to the RT efficacy in clinically relevant models of cancer?

Pancreatic cancer (PanCa) remains a lethal disease for which RT is part of the palliative care and for which PDT demonstrated promising results in clinical trial. We thus evaluated the combination of low-dose PDT and RT delivered in absence of nanoscintillators on various heterocellular spheroid models that recapitulate the clinical heterogeneity of PanCa. Although therapeutic effects emerged at different timepoints in each model, the RT/PDT combination uniformly achieved favorable outcomes. With RT providing stunted tumor growth while PDT drove adjuvant apoptotic and necrotic cell death, the combination produced significantly smaller and less viable PanCa spheroids.

In conclusion, the beneficial RT/PDT treatment outcomes encourage the further development of nanoscinitillators for X-ray-activated PDT. Assessment of such combination treatments should encompass multiparametric and temporally-spaced assessment of treatment effects in preclinical cancer models.

Impact of Enhanced Recovery after Surgery protocol on immediate surgical outcome in elderly patients undergoing pancreaticoduodenectomy

The numbers of patients undergoing pancreaticoduodenectomy are increasing and considerable percentage is elderly patients. Pancreaticoduodenectomy is a major and complicated surgery. The morbidity and mortality following pancreaticoduodenectomy have significantly reduced in recent times; it still remains unclear in elderly patients. Applications of Enhanced Recovery after Surgery protocol have contributed for this better outcome. In this retrospective study, patients who underwent pancreaticoduodenectomy with Enhanced Recovery after Surgery protocol were included and divided into two groups (< 60 years vs ≥ 60 years). The "elderly patients" (≥ 60 years) were defined based on the WHO definition for Indian subcontinent. Outcomes were analyzed in terms of postoperative morbidity, mortality and length of hospital stay. Total 103 patients underwent pancreaticoduodenectomy during the study period (January 2012-December 2017). The mean age was 56.6 ± 10.32 years. Fifty-six (54.37%) patients were aged < 60 years (young group) and 47 (45.63%) patients were aged ≥ 60 years (elderly group). There was no difference between the groups in terms of age, gender, co-morbidity, preoperative drainage and diagnosis. There was no significant difference in the morbidity and mortality (p > 0.05). Delayed gastric emptying was the most common complication which was 25.24% (21% vs 23.41%). Pancreatic fistula rate was 13.59% (8.9% vs 12.76%) and hemorrhage was 4.85% (5.4% vs 4.3%). Mortality was 4.85%. Postoperative hospital stay was comparable (14.7 days vs 15.3 days) (p = 0.164). Pancreaticoduodenectomy is a safe surgical procedure in elderly patients in comparison to young patients. Application of Enhanced Recovery after Surgery protocol can improve the outcome further.

PET imaging of Hsp90 expression in pancreatic cancer using a new 64Cu-labeled dimeric Sansalvamide A decapeptide

Heat shock protein 90 (Hsp90) plays a vital role in the progress of malignant disease and elevated Hsp90 expression has been reported in pancreatic cancer. In this study, we radiolabeled a dimeric Sansalvamide A derivative (Di-San A1) with ⁶⁴Cu, and evaluated the feasibility of using ⁶⁴Cu-Di-San A1 for PET imaging of Hsp90 expression in a mouse model of pancreatic cancer. A macrocyclic chelator NOTA (1,4,7-triazacyclononane-1,4,7-trisacetic acid) was conjugated to Di-San A1. ⁶⁴Cu-Di-San A1 was successfully prepared in a radiochemical yield > 97% with a radiochemical purity > 98%. ⁶⁴Cu-Di-San A1 is stable in PBS and mouse serum with > 92% of parent probe intact after 4 h incubation. The cell binding and uptake revealed that ⁶⁴Cu-Di-San A1 binds to Hsp90-positive PL45 pancreatic cancer cells, and the binding can be effectively blocked by an Hsp90 inhibitor (17AAG). For microPET study, ⁶⁴Cu-Di-San A1 shows good in vivo performance in terms of tumor uptake in nude mice bearing PL45 tumors. The Hsp90-specific tumor activity accumulation of ⁶⁴Cu-Di-San A1 was further demonstrated by significant reduction of PL45 tumor uptake with a pre-injected blocking dose of 17AAG. The ex vivo PET imaging and biodistribution results were consistent with the quantitative analysis of PET imaging, demonstrating good tumor-to-muscle ratio (5.35 ± 0.46) of ⁶⁴Cu-Di-San A1 at 4 h post-injection in PL45 tumor mouse xenografts. ⁶⁴Cu-Di-San A1 allows PET imaging of Hsp90 expression in PL45 tumors, which may provide a non-invasive method to quantitatively characterize Hsp90 expression in pancreatic cancer.

Diagnostic yield of EUS-FNA of small (≤15 mm) solid pancreatic lesions using a 25-gauge needle

BACKGROUND

Early detection of small solid pancreatic lesions is increasingly common. To date, few and contradictory data have been published about the relationship between lesion size and endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) diagnostic yield. The aim of this study was to assess the relation between the size of solid pancreatic lesions and the diagnostic yield of EUS-FNA using a 25-gauge needle in a center without available rapid on-site evaluation.

METHODS

In the retrospective cohort study, we selected patients who underwent EUS-FNA for solid pancreatic lesions with a 25-gauge needle from October 2014 to October 2015. Patients were divided into three groups (≤15 mm, 16-25 mm and >25 mm), and the outcomes were compared.

RESULTS

We analyzed 163 patients. Overall adequacy, sensitivity, specificity and accuracy were 85.2%, 81.8%, 93.7%, and 80.4%, respectively. When stratified by size, the sensitivity and accuracy correlated with size (P = 0.016 and P = 0.042, respectively). Multivariate analysis showed that lesion size was the only independent factor (P = 0.019, OR = 4.76) affecting accuracy. The role of size as an independent factor affecting accuracy was confirmed in a separate multivariate analysis, where size was included in the model as a covariate (P = 0.018, OR = 1.08).

CONCLUSION

Our study demonstrates that, in the absence of rapid on-site evaluation, mass size affects the accuracy of EUS-FNA of solid pancreatic lesions.

Differential diagnosis of small solid pancreatic lesions

BACKGROUND AND AIMS

Pancreatic ductal adenocarcinoma (PDAC) is typically diagnosed at a late stage. Little is known about the incidental finding of early-stage PDAC. The aim of the current study was to determine the etiology of small solid pancreatic lesions (≤15 mm) to optimize clinical management.

METHODS

Inclusion criterion for the retrospective study analysis was the incidental finding of primarily undetermined small solid pancreatic lesions ≤15 mm in 394 asymptomatic patients. Final diagnoses were based on histology or cytology obtained by imaging-guided biopsy (and at least 12-month follow-up) and/or surgery. Contrast-enhanced US or contrast-enhanced EUS was performed in 219 patients.

RESULTS

The final diagnoses of 394 patients were as follows: 146 PDACs, 156 neuroendocrine tumors, 28 metastases into the pancreas from other primary sites, and 64 various other etiologies. Contrast-enhanced US allowed differential diagnosis of PDAC and non-PDAC in 189 of 219 patients (86%).

CONCLUSIONS

Approximately 40% of patients with small solid pancreatic lesions had very early stage PDAC. Approximately 60% of small solid pancreatic lesions ≤15 mm are not PDAC and, therefore, do not require radical surgery. Without preoperative diagnosis, an unacceptably large proportion of patients would be exposed to radical surgery with significant morbidity and mortality.

Clinical outcomes of pancreaticoduodenectomy in octogenarians: a surgeon's experience from 2007 to 2015

BACKGROUND

As the number of elderly people in our population increases, there will be a greater number of octogenarians who will need pancreaticoduodenectomy as the only curative option for periampullary malignancies. This study evaluated clinical outcomes of pancreaticoduodenectomy in octogenarians, in comparison to younger patients.

METHODS

A retrospective review was conducted of 216 consecutive patients who underwent pancreaticoduodenectomy from January 2007 to April 2015. A two-sided Fisher's exact statistical analysis was used to compare pre-operative comorbidities, intra-operative factors, surgical pathology, and post-operative complication rates between non-octogenarians and octogenarians.

RESULTS

One hundred and eighty three non-octogenarians and 33 octogenarians underwent pancreaticoduodenectomy. Of patients with periampullary adenocarcinoma, octogenarians were more likely to present with advanced disease state (P=0.01). The two cohorts had similar ASA scores (P=0.62); however, octogenarians were more likely to have coronary artery disease (P=0.03). The length of operation was shorter in octogenarians (P=0.002). Mortality rates (P=0.49) and overall postoperative complication rates (P=1.0) were similar in two cohorts; however octogenarians had a higher incidence of pulmonary embolism (P=0.02).

CONCLUSIONS

Our data demonstrates that octogenarians can undergo pancreaticoduodenectomy with outcomes similar to those in younger patients. Thus, patients should not be denied a curative surgical option for periampullary malignancy based on advanced age alone.

Soluble B7-H3 promotes the invasion and metastasis of pancreatic carcinoma cells through the TLR4/NF-κB pathway

Many studies have demonstrated a relationship between soluble B7-H3 (sB7-H3) and the poor prognosis of patients with malignant tumors, and increasing evidence has shown a connection between sB7-H3 and NF-κB in tumor progression. In the present study, we demonstrate for the first time that sB7-H3 promotes the invasion and metastasis of pancreatic carcinoma cells through the TLR4/NF-κB pathway. In this study, we observed that sB7-H3 was highly expressed in mB7-H3-positive pancreatic carcinoma (PCa) cells. Exogenous sB7-H3 significantly increased NF-κB activity and promoted the migration and invasion of PCa cells. Further studies proved that sB7-H3 first up-regulated TLR4 expression, then activated NF-κB signaling and finally promoted IL-8 and VEGF expression. In contrast, the silencing of TLR4 using a stable short hairpin RNA significantly decreased the sB7-H3-induced activity of NF-κB and the expression of IL-8 and VEGF in PCa cells. In vivo animal experiments further demonstrated that TLR4-knock-down tumor cells displayed a decreased ability to metastasize compared with the control tumor cells after being induced by sB7-H3. Collectively, these results demonstrate that sB7-H3 promotes invasion and metastasis through the TLR4/NF-κB pathway in pancreatic carcinoma cells.

A model to predict survival following pancreaticoduodenectomy for malignancy based on tumour site, stage and lymph node ratio

BACKGROUND

Site of tumour origin, lymph node metastases and lymph node ratio (LNR) are identified as important factors determining prognosis in patients undergoing pancreaticoduodenectomy (PD). This study hypothesised that a prognostic index to predict survival could be developed through statistical modelling based on these pathological variables.

METHODS

Patients who underwent PD between 2004 and 2013 were included. Univariable and multivariable (Cox regression) analyses were performed to identify predictors of survival, and a prognostic index was derived. The prognostic index was then validated using an external patient cohort.

RESULTS

A total of 567 patients who underwent PD were used as a derivation cohort. Tumour site (p < 0.001), tumour size (p = 0.002), T-stage (p < 0.001), vascular involvement (p = 0.002), number of positive nodes (p < 0.001) and LNR (p < 0.001) were significantly associated with survival in univariable analysis. LNR (p < 0.001), tumour site (p < 0.001), T-stage (p = 0.007) remained significant predictors of survival in multivariable analysis, and were combined to derive a prognostic index. The accuracy of the prognostic index was assessed both on the original cohort, and a validation set of 194 patients from another institutional prospective database. The AUROC scores for predicting the overall survival at 3 years were 0.77 in the derivation cohort and 0.74 in the validation cohort.

CONCLUSION

The Pancreaticoduodenectomy Prognostic Index is a validated clinico-pathological model based on tumour site, T-stage and LNR to predict long-term survival following PD.

Pancreatic cancer: current management and treatment strategies

The 5-year survival of patients with pancreatic cancer is poor and, despite oncological advances over the past two decades, has not significantly improved. However, there have been several surgical and oncological advances which have improved morbidity and mortality in surgery and more efficacious chemotherapy regimens, resulting in a better patient experience and an increase in survival by a number of months. Most patients have a tumour at the head of the pancreas and those with resectable disease undergo a pancreaticoduodenectomy, which can be performed laparoscopically. Those who have a pancreatic resection have an increased survival in comparison with those receiving oncological treatment only; however, only a quarter of patients have resectable disease at diagnosis. Some centres are now performing venous resections and/or arterial resections in order to increase the number of patients eligible for curative surgery. Innovative techniques using ablation technologies to downstage tumours for resection are also being investigated. After surgery, all patients should be offered adjuvant gemcitabine-based chemotherapy. Those with locally advanced tumours not suitable for surgery should be offered FOLFIRINOX chemotherapy, after which the tumour may be suitable for surgical resection. The use of radiotherapy in this group of patients is controversial but offered by a few centres. Patients with metastatic disease at diagnosis should also be offered FOLFIRINOX chemotherapy, which can improve survival by a few months. As our knowledge of the tumour biology of pancreatic cancer progresses, a number of new agents targeting specific genes and proteins are under investigation and there is hope that median survival will continue to improve over the next decade.

Imaging and Therapy of Pancreatic Cancer with Phosphatidylserine-Targeted Nanovesicles

Pancreatic cancer remains one of the most intractable cancers, with a dismal prognosis reflected by a 5-year survival of ~6%. Since early disease symptoms are undefined and specific biomarkers are lacking, about 80% of patients present with advanced, inoperable tumors that represent a daunting challenge. Despite many clinical trials, no single chemotherapy agent has been reliably associated with objective response rates above 10% or median survival longer than 5 to 7 months. Although combination chemotherapy regimens have in recent years provided some improvement, overall survival (8-11 months) remains very poor. There is therefore a critical need for novel therapies that can improve outcomes for pancreatic cancer patients. Here, we present a summary of the current therapies used in the management of advanced pancreatic cancer and review novel therapeutic strategies that target tumor biomarkers. We also describe our recent research using phosphatidylserine-targeted saposin C-coupled dioleoylphosphatidylserine nanovesicles for imaging and therapy of pancreatic cancer.

Neoadjuvant vs adjuvant therapy for resectable pancreatic cancer: the evolving role of radiation

A major challenge with pancreatic cancer management is in the discrimination of clearly resectable tumors from those that would likely be accompanied by a positive resection margin if upfront surgery was attempted. The standard of care for clearly resectable pancreatic cancer remains surgery followed by adjuvant therapy, but there is considerable controversy over whether such therapeutic adjuvant strategies should include radiotherapy. Furthermore, in a malignancy with such high rates of distant metastasis, investigators are now exploring the feasibility and outcomes of delivering therapy in the neoadjuvant setting, both for clearly resectable as well as borderline resectable tumors. In this review, we explore the current standard of care of upfront surgery for clearly resectable cancers followed by adjuvant therapy, focusing on the role of radiotherapy. We highlight the difficulties in interpreting a literature fraught with inconsistencies in how resectable vs borderline resectable cancers are defined and treated. Finally, we explore the role of neoadjuvant strategies in the modern era.

Is routine drainage necessary after pancreaticoduodenectomy?

With the development of imaging technology and surgical techniques, pancreatic resections to treat pancreatic tumors, ampulla tumors, and other pancreatic diseases have increased. Pancreaticoduodenectomy, one type of pancreatic resection, is a complex surgery with the loss of pancreatic integrity and various anastomoses. Complications after pancreaticoduodenectomy such as pancreatic fistulas and anastomosis leakage are common and significantly associated with patient outcomes. Pancreatic fistula is one of the most important postoperative complications; this condition can cause intraperitoneal hemorrhage, septic shock, or even death. An effective way has not yet been found to avoid the occurrence of pancreatic fistula. In most medical centers, the frequency of pancreatic fistula has remained between 9% and 13%. The early detection and routine drainage of anastomotic fistulas, pancreatic fistulas, bleeding, or other intra-abdominal fluid collections after pancreatic resections are considered as important and effective ways to reduce postoperative complications and the mortality rate. However, many recent studies have argued that routine drainage after abdominal operations, including pancreaticoduodenectomies, does not affect the incidence of postoperative complications. Although inserting drains after pancreatic resections continues to be a routine procedure, its necessity remains controversial. This article reviews studies of the advantages and disadvantages of routine drainage after pancreaticoduodenectomy and discusses the necessity of this procedure.

Pancreatic surgery: indications, complications, and implications for nutrition intervention

Pancreatic surgery is a complicated procedure leaving postoperative patients with an altered gastrointestinal (GI) anatomy and a potential for further surgical complications such as leaks and fistulas. Beyond surgical complications, these patients are prone to delayed gastric emptying, fat malabsorption, and hyperglycemia, with early satiety and poor appetite further compromising nutrition status. Many of these patients are malnourished prior to this major surgical procedure, and significant weight loss is common postoperatively. Does this affect their outcome? There seems to be a lack of consensus in this patient population regarding how to optimize nutrition and limit potential deleterious effects of this surgery. It is important to first understand the underlying disease condition and the effects to the gland, different forms of surgery with subsequent GI alterations, and common surgical and digestive complications. Once this is reviewed, existing nutrition support literature will be explored in attempts to determine the best nutrition management in this patient population.

Viral therapy for pancreatic cancer: tackle the bad guys with poison

Pancreatic cancer is one of the most devastating diseases with very poor prognosis. Only a small proportion is curable by surgical resection, whilst standard chemotherapy for patients with advanced disease has only modest effect with substantial toxicity. Therefore, there is an urgent need for the development of novel therapeutic approaches to improve the patient outcome. Recently the viral therapy is emerging as a novel effective therapeutic approach for cancer with the potential to selectively treat both primary tumor and metastatic lesions. This review provides an overview of the current status of viral treatment for pancreatic cancer, both in the laboratories and in clinical settings.