Pancreatic resection for intraductal papillary mucinous neoplasm- a thirteen-year single center experience

Recurrence following Resection of Intraductal Papillary Mucinous Neoplasms: A Systematic Review to Guide Surveillance

Patients who undergo resection for non-invasive IPMN are at risk for long-term recurrence. Further evidence is needed to identify evidence-based surveillance strategies based on the risk of recurrence. We performed a systematic review of the current literature regarding recurrence patterns following resection of non-invasive IPMN to summarize evidence-based recommendations for surveillance. Among the 61 studies reviewed, a total of 8779 patients underwent resection for non-invasive IPMN. The pooled overall median follow-up time was 49.5 months (IQR: 38.5-57.7) and ranged between 14.1 months and 114 months. The overall median recurrence rate for patients with resected non-invasive IPMN was 8.8% (IQR: 5.0, 15.6) and ranged from 0% to 27.6%. Among the 33 studies reporting the time to recurrence, the overall median time to recurrence was 24 months (IQR: 17, 46). Existing literature on recurrence rates and post-resection surveillance strategies for patients with resected non-invasive IPMN varies greatly. Patients with resected non-invasive IPMN appear to be at risk for long-term recurrence and should undergo routine surveillance.

Systematic review of challenging issues in pathology of intraductal papillary mucinous neoplasms

BACKGROUND

Intraductal papillary mucinous neoplasms (IPMNs) are a cystic precursor to pancreatic cancer. IPMNs deemed clinically to be at high-risk for malignant progression are frequently treated with surgical resection, and pathological examination of the pancreatectomy specimen is a key component of the clinical care of IPMN patients.

METHODS

Systematic literature reviews were conducted around eight topics of clinical relevance in the examination of pathological specimens in patients undergoing resection of IPMN.

RESULTS

This review provides updated perspectives on morphological subtyping of IPMNs, classification of intraductal oncocytic papillary neoplasms, nomenclature for high-grade dysplasia, assessment of T stage, distinction of carcinoma associated or concomitant with IPMN, role of molecular assessment of IPMN tissue, role of intraoperative assessment by frozen section, and preoperative evaluation of cyst fluid cytology.

CONCLUSIONS

This analysis provides the foundation for data-driven approaches to several challenging issues in the pathology of IPMNs.

Comparing Survival after Resection of Pancreatic Cancer with and without Pancreatic Cysts: Nationwide Registry-Based Study

Background: Outcome after resection of pancreatic ductal adenocarcinoma associated with pancreatic cystic neoplasms (PCN-PDAC) might differ from PDAC not associated with PCN. This nationwide, registry-based study aimed to compare the overall survival (OS) in these patients. Methods: Data from consecutive patients after pancreatic resection for PDAC between 2013 and 2018 were matched with the corresponding pathology reports. Primary outcome was OS for PCN-PDAC and PDAC including 1-year and 5-year OS. Cox regression analysis was used to correct for prognostic factors (e.g., pT-stage, pN-stage, and vascular invasion). Results: In total, 1994 patients underwent resection for PDAC including 233 (12%) with PCN-PDAC. Median estimated OS was better in patients with PCN-PDAC (34.5 months [95%CI 25.6 to 43.5]) as compared to PDAC not associated with PCN (18.2 months [95%CI 17.3 to 19.2]; hazard ratio 0.53 [95%CI 0.44−0.63]; p < 0.001). The difference in OS remained after correction for prognostic factors (adjusted hazard ratio 1.58 [95%CI 1.32−1.90]; p < 0.001). Conclusions: This nationwide registry-based study showed that 12% of resected PDAC were PCN-associated. Patients with PCN-PDAC had better OS as compared to PDAC not associated with PCN.

Pancreatic ductal adenocarcinomas associated with intraductal papillary mucinous neoplasms (IPMNs) versus pseudo-IPMNs: relative frequency, clinicopathologic characteristics and differential diagnosis

The literature is highly conflicted on what percentage of pancreatic ductal adenocarcinomas (PDACs) arise in association with intraductal papillary mucinous neoplasms (IPMNs). Some studies have claimed that even small (Sendai-negative) IPMNs frequently lead to PDAC. Recently, more refined pathologic definitions for mucin-lined cysts were provided in consensus manuscripts, but so far there is no systematic analysis regarding the frequency and clinicopathologic characteristics of IPMN-mimickers, i.e., pseudo-IPMNs. In this study, as the first step in establishing frequency, we performed a systematic review of the pathologic findings in 501 consecutive ordinary PDACs, which disclosed that 10% of PDACs had associated cysts ≥1 cm. While 31 (6.2%) of these were IPMN or mucinous cystic neoplasm (MCN), 19 (3.8%) were other cyst types that mimicked IPMN (pseudo-IPMNs) per recent WHO/consensus criteria. As the second step of the study, we performed a comparative clinicopathologic analysis by also including our entire surgical pathology/consultation databases that was comprised of 60 IPMN-associated PDACs, 30 MCN-associated PDACs and 40 pseudo-IPMN-associated PDACs. We found that 84% of true IPMNs were pre-operatively recognized, whereas IPMN was considered in differential diagnosis of 33% of pseudo-IPMNs. Of the 40 pseudo-IPMNs, there were 15 secondary duct ectasias; 6 large-duct-type PDACs; 5 pseudocysts; 5 cystic tumor necrosis; 4 simple mucinous cysts; 3 groove pancreatitis-associated paraduodenal wall cysts; and 2 congenital cysts. Microscopically, pseudo-IPMNs had at least partial mucinous-lining mimicking IPMN but had smaller cystic (mean = 1.9 cm) and larger PDAC (mean = 3.8 cm) components compared to true IPMNs (cyst = 5.7 cm; PDAC = 2.0 cm). In summary, in this pathologically verified analysis that utilized refined criteria, 10% of PDACs were discovered to have cysts ≥1 cm, about two-thirds of which were IPMN/MCN but about one-third were pseudo-IPMNs. True IPMNs underlying the PDACs are often large and are already diagnosed pre-operatively as having an IPMN component, whereas only a third of the pseudo-IPMNs receive IPMN diagnosis by imaging and their cysts are smaller. At the histopathologic level, pseudo-IPMNs are highly prone to misdiagnosis as IPMN, which presumably accounts for much higher association of IPMNs with PDAC as reported in some studies. The subtle but salient characteristics of pseudo-IPMNs elucidated in this study should be combined with careful radiological/clinical correlation in order to exclude pseudo-IPMNs.

Carbohydrate Antigen 19-9 Is an Invasive Malignancy Preoperative Prognostic Factor for Intraductal Papillary Mucinous Neoplasms

INTRODUCTION

This study aimed to determine the preoperative clinicophysiological and postoperative clinicopathological predictors of malignancy in patients with intraductal papillary mucinous neoplasm (IPMN).

METHODS

This was a retrospective observational study. We included 121 patients (73 men and 48 women; mean age: 68.7 years) who had undergone pancreatic resection for IPMN between 2007 and 2018. These patients were grouped into invasive carcinoma (IPMN-INV, N = 21) and low/high-grade IPMN (IPMN-LG/HG, N = 100) groups. Univariate and multivariate analyses of clinicophysiological parameters were carried out. These parameters were also compared between the IPMN-INV/HG (N = 53) and IPMN-LG (N = 68) groups. Survival analyses according to macroscopic type and IPMN subtypes were performed.

RESULTS

On univariate analysis, age (p = 0.038), carbohydrate antigen (CA) 19-9 (p < 0.001), IPMN macroscopic type (p = 0.001), IPMN subtype (p < 0.001), pancreatic duct diameter (p < 0.001), and mural nodule (p = 0.042), between IPMN-INV and IPMN-LG/HG were found to be significant prognostic factors of malignancy. CA 19-9 was found to be an independent prognostic factor of IPMN malignancy on multivariate analysis (p = 0.035). The 1-, 3-, and 5-year overall survival (OS) rates of the IPMN-INV and IPMN-LG/HG groups were 94.4/100%, 94.4/100%, and 67.2/100%, respectively. The OS rate in the IPMN-LG/HG group was significantly higher than that in the IPMN-INV group (p < 0.001). On univariate analysis, platelet (p = 0.043), CA 19-9 (p = 0.039), prognostic nutritional index (p = 0.034), platelet/lymphocyte ratio (p = 0.01), IPMN macroscopic type (p < 0.001), IPMN subtype (p < 0.001), pancreatic duct diameter (p = 0.036), and mural nodule (p = 0.032) between IPMN-INV/HG and IPMN-LG were found to be significant prognostic factors of malignancy. On multivariate analysis, CA 19-9 was found to be an independent prognostic factor (p = 0.042) between IPMN-INV/HG and IPMN-LG of malignancy. The 1-, 3-, and 5-year OS rates of the IPMN-INV/HG and IPMN-LG groups were 97.9/100%, 97.9/100%, and 82.6/100%, respectively. The OS rate was significantly higher in the IPMN-LG group than in the IPMN-INV/HG group (p = 0.03). No significant differences in survival were observed in patients with macroscopic tumors (p= 0.544).

CONCLUSION

CA 19-9 is an independent invasive malignancy predictor of IPMN.

Complete resection of the gastric antrum decreased incidence and severity of delayed gastric emptying after pancreaticoduodenectomy

BACKGROUND

Delayed gastric emptying (DGE) is the main complication after pancreaticoduodenectomy (PD), but the mechanism is still unclear. The aim of this study was to elucidate the role of complete resection of the gastric antrum in decreasing incidence and severity of DGE after PD.

METHODS

Sprague-Dawley rats were divided into three groups: expanded resection (ER group), complete resection (CR group), and incomplete resection (IR group) of the gastric antrum. The tension (g) of remnant stomach contraction was observed. We analyzed the histological morphology of the gastric wall by different excisional methods after distal gastrectomy. Moreover, patients underwent PD at our department between January 2012 and May 2016 were included in the study. These cases were divided into IR group and CR group of the gastric antrum, and the clinical data were retrospectively analyzed.

RESULTS

The ex vivo remnant stomachs of CR group exhibited much greater contraction tension than others (P < 0.05). The contraction tension of the remnant stomach increased with increasing acetylcholine concentration, while remained stable at the concentration of 10 × 10^-5 mol/L. Furthermore, 174 consecutive patients were included and retrospectively analyzed in the study. The incidence of DGE was significantly lower (3.5% vs. 21.3%, P < 0.01) in CR group than in IR group. In addition, hematoxylin-eosin staining analyses of the gastric wall confirmed that the number of transected circular smooth muscle bundles were higher in IR group than in CR group (8.24 ± 0.65 vs. 3.76 ± 0.70, P < 0.05).

CONCLUSIONS

The complete resection of the gastric antrum is associated with decreased incidence and severity of DGE after PD. Gastric electrophysiological and physiopathological disorders caused by damage to gastric smooth muscles might be the mechanism underlying DGE.

Intraductal papillary-mucinous carcinoma with portal vein tumor thrombus and multifocal liver metastasis: An autopsy case

The prognosis of intraductal papillary-mucinous neoplasm is superior to that of conventional pancreatic ductal adenocarcinoma. Only a few advanced cases of intraductal papillary-mucinous carcinoma (IPMC) have been reported to date. We herein report the case of a 78-year-old male patient with advanced pancreatobiliary type IPMC with portal vein invasion and liver metastasis. The IPMC invaded the portal vein to form a tumor thrombus and it also metastasized to the liver via the portal vein. After receiving best supportive care, the patient succumbed to the disease following an exacerbation of IPMC 90 days after the initial presentation. On autopsy, a very long tumor thrombus was identified, along with liver metastatic lesions, which had retained the structure of the primary IPMC on histological examination.

Intraductal papillary mucinous carcinoma versus pancreatic ductal adenocarcinoma: A systematic review and meta-analysis

BACKGROUND

Previous studies have indicated that there may be a difference in tumor biology between intraductal papillary mucinous carcinoma (IPMC) and pancreatic ductal adenocarcinoma (PDAC). However, the data are still controversial. The aim of this systematic review and meta-analysis was to summarize and compare the outcome of IPMC and PDAC after surgical resection.

METHODS

Studies comparing IPMC and PDAC were identified using Medline and Embase search engines. Primary outcomes of interest were survival and recurrence. Secondary outcomes were clinicopathological characteristics. Meta-analysis of data was conducted using a random-effects model.

RESULTS

A total of 14 studies were included. Pooled analysis revealed an improved 5-year overall survival (OS) for IPMC compared to PDAC (OR 0.23, 95% CI 0.09-0.56). Both colloid and tubular IPMC showed improved 5-year OS compared to PDAC (OR 0.12, 95% CI 0.05-0.25 and OR 0.38, 95% CI 0.26-0.54, respectively). Median survival time ranged from 21 to 58 months in the IPMC group compared to 12-23 months in the PDAC group. No meta-analysis could be performed on recurrence or on time-to-event data. Descriptive data showed no survival difference for higher TNM stages. IPMC was more often found at a TNM-stage of 1 (OR 4.40, 95% CI 2.71-7.15) and had lower rates of lymph node spread (OR 0.43, 95% CI 0.32-0.57).

CONCLUSION

Available data suggest that IPMC has a more indolent course with a better 5-year OS compared to PDAC. The histopathological features are less aggressive in IPMC. The reason may be earlier detection. However, for IPMC with higher TNM stages the survival seems to be similar to that of PDAC.

Potential ceRNA networks involved in autophagy suppression of pancreatic cancer caused by chloroquine diphosphate: A study based on differentially‑expressed circRNAs, lncRNAs, miRNAs and mRNAs

Autophagy has been reported to be involved in the occurrence and development of pancreatic cancer. However, the mechanism of autophagy‑associated non‑coding RNAs (ncRNAs) in pancreatic cancer remains largely unknown. In the present study, microarrays were used to detect differential expression of mRNAs, microRNAs (miRNAs), long ncRNAs (lncRNAs) and circular RNAs (circRNAs) post autophagy suppression by chloroquine diphosphate in PANC‑1 cells. Collectively, 3,966 mRNAs, 3,184 lncRNAs and 9,420 circRNAs were differentially expressed. Additionally, only two miRNAs (hsa‑miR‑663a‑5p and hsa‑miR‑154‑3p) were underexpressed in the PANC‑1 cells in the autophagy‑suppression group. Furthermore, miR‑663a‑5p with 9 circRNAs, 8 lncRNAs and 46 genes could form a prospective ceRNA network associated with autophagy in pancreatic cancer cells. In addition, another ceRNA network containing miR‑154‑3p, 5 circRNAs, 2 lncRNAs and 11 genes was also constructed. The potential multiple ceRNA, miRNA and mRNA associations may serve pivotal roles in the autophagy of pancreatic cancer cells, which lays the theoretical foundation for subsequent investigations on pancreatic cancer.

Robotic pancreatic surgery: old concerns, new perspectives

BACKGROUND

Described for the first time in 2003, the robotic pancreatic surgery shows interesting results. The evaluation of post-operative outcomes is necessary once we describe an innovative surgical approach.

METHODS

We have performed a retrospective analysis of a prospectively maintained database on robotic pancreatic surgery including malignant and benign indications for surgery.

RESULTS

A total of 50 consecutive patients underwent robotic pancreatic surgery (26 pancreatico duodenectomy and 24 distal pancreatectomy) between January 2012 and July 2015 in a single centre. The overall operative time was 425 (390-620) min. In a subgroup of highly selected malignant tumours, we were able to achieve 88% of R0 resection with robotic approach. A number of lymphnodes rose significantly with growing experience (p = .025). The overall major complication rate (15%), as well as pancreatic fistula rate (16%) were acceptable. The two-year overall survival for the whole group was 65%.

CONCLUSION

The robotic pancreatic surgery in a highly selected group of patients seems safe and feasible. The cost-effectiveness and long-term oncologic outcomes need further investigations.