Concomitant Intraductal Papillary Mucinous Neoplasm in Pancreatic Ductal Adenocarcinoma Is an Independent Predictive Factor for the Occurrence of New Cancer in the Remnant Pancreas. Ann Surg. 2020;271:941-948. [PMID: 30308608 DOI: 10.1097/sla.0000000000003060]

CT findings and clinical effects of high grade pancreatic intraepithelial neoplasia in patients with intraductal papillary mucinous neoplasms

PURPOSE

To investigate the common CT findings of high-grade (HG) PanIN and clinical effects in the remnant pancreas in patients with intraductal papillary mucinous neoplasm (IPMN) of the pancreas.

MATERIALS AND METHODS

Two hundred fifty-one patients with surgically confirmed IPMNs (118 malignant [invasive carcinoma/high-grade dysplasia] and 133 benign [low-grade dysplasia]) were retrospectively enrolled. The grade of PanIN (233 absent/low-grade and 18 high-grade) was recorded, and all patients underwent serial CT follow-up before and after surgery. Two radiologists analyzed CT findings of high-risk stigmata or worrisome features according to 2017 international consensus guidelines. They also analyzed tumor recurrence on serial follow-up CT after surgery. Statistical analyses were performed to identify significant predictors and clinical impact on postoperative outcomes of HG PanIN.

RESULTS

PanIN grade showed a significant association with IPMN grade (p = 0.012). Enhancing mural nodules ≥5 mm, abrupt main pancreatic duct (MPD) changes with distal pancreatic atrophy, increased mural nodule size and MPD diameter were common findings in HG PanIN (P<0.05). In multivariate analysis, abrupt MPD change with distal pancreatic atrophy (odds ratio (OR) 6.59, 95% CI: 2.32-18.72, <0.001) and mural nodule size (OR, 1.05; 95% CI, 1.02-1.08, 0.004) were important predictors for HG PanIN. During postoperative follow-up, HG PanIN (OR, 4.98; 95% CI, 1.22-20.33, 0.025) was significantly associated with cancer recurrence in the remnant pancreas.

CONCLUSION

CT can be useful for predicting HG PanIN using common features, such as abrupt MPD changes and mural nodules. In HG PanIN, extra caution is needed to monitor postoperative recurrence during follow-up.

Optimal Surveillance Interval of Branch Duct Intraductal Papillary Mucinous Neoplasm of the Pancreas

Importance

Despite the increasing prevalence of intraductal papillary mucinous neoplasm (IPMN), data on the growth and malignant conversion rates based on long-term surveillance cohorts are limited. Many international guidelines recommend surveillance for benign lesions, but the optimal interval and duration are unclear.

Objective

To determine the optimal surveillance protocol for IPMN and propose which patients may be exempted from surveillance.

Design, Setting, and Participants

This large-scale, international cohort study examined data of 3825 patients with IPMN treated at 5 tertiary pancreatic centers. Included were patients with branch duct (BD) IPMN who underwent surveillance or surgery between January 1, 1988, and December 31, 2020. After a thorough review, 3656 patients were included in the analytic sample. Changes in cyst size, worrisome features or high-risk stigmata, and malignant conversion rates were assessed. Patients who underwent surveillance over 5 years were compared to suggest discontinuation of surveillance protocol. Clinical data collection began in January 1, 2021, and the mean (SD) follow-up duration was 84 (47.7) months. The data analysis was performed from May 2, 2022, through September 14, 2022.

Exposure

The patients with BD-IPMN were followed up based on International Association of Pancreatology guidelines. Patients with suspicious malignant neoplasms during surveillance underwent surgical resection.

Main Outcome and Measures

The main outcome of this study was the optimal follow-up interval and duration of BD-IPMN surveillance. The association among cyst size, growth rate, and progression was examined using descriptive statistics.

Results

Of the 3656 patients with BD-IPMN in the analytic sample (1973 [54.0%] female; mean [SD] age, 63.7 [10.2] years), 172 (4.7%) were confirmed to have malignant lesions through surgery. Considering cyst growth, the time to develop worrisome features, and malignant conversion, a 1.5-, 1-, and 0.5-year surveillance interval could be optimal for cysts smaller than 20 mm, 20 to 30 mm, and 30 mm, respectively, after initial short-term (6-month) follow-up. Patients with cysts smaller than 20 mm, no worrisome features, and no growth during 5-year surveillance did not show malignant conversion after 5 years of follow-up and had time to progression of greater than 10 years.

Conclusions

These findings suggest that BD-IPMN surveillance may depend on the size of the cyst and morphologic changes at the initial 6-month follow-up. For patients with small cysts (ie, <20 mm) with no morphologic changes during the initial 5-year surveillance period, surveillance may be discontinued for those unfit for surgery or who have a limited life expectancy of 10 years or less.

International evidence-based Kyoto guidelines for the management of intraductal papillary mucinous neoplasm of the pancreas

This study group aimed to revise the 2017 international consensus guidelines for the management of intraductal papillary mucinous neoplasm (IPMN) of the pancreas, and mainly focused on five topics; the revision of high-risk stigmata (HRS) and worrisome features (WF), surveillance of non-resected IPMN, surveillance after resection of IPMN, revision of pathological aspects, and investigation of molecular markers in cyst fluid. A new development from the prior guidelines is that systematic reviews were performed for each one of these topics, and published separately to provide evidence-based recommendations. One of the highlights of these new "evidence-based guidelines" is to propose a new management algorithm, and one major revision is to include into the assessment of HRS and WF the imaging findings from endoscopic ultrasound (EUS) and the results of cytological analysis from EUS-guided fine needle aspiration technique, when this is performed. Another key element of the current guidelines is to clarify whether lifetime surveillance for small IPMNs is required, and recommends two options, "stop surveillance" or "continue surveillance for possible development of concomitant pancreatic ductal adenocarcinoma", for small unchanged BD-IPMN after 5 years surveillance. Several other points are also discussed, including identifying high-risk features for recurrence in patients who underwent resection of non-invasive IPMN with negative surgical margin, summaries of the recent observations in the pathology of IPMN. In addition, the emerging role of cyst fluid markers that can aid in distinguishing IPMN from other pancreatic cysts and identify those IPMNs that harbor high-grade dysplasia or invasive carcinoma is discussed.

Minimally invasive enucleation of pancreatic tumors: The main pancreatic duct is no longer a restricted area

Background

Tumors involving the main pancreatic duct (MPD) used to be a contraindication for enucleation.

Methods

Clinical data of consecutive patients with pancreatic tumors who received laparoscopic or robotic enucleation (LEN or REN) between January 2019 and December 2021 at Fudan University Shanghai Cancer Center were analyzed.

Results

Ninety-six patients were included in the analysis, with 55 in the LEN group and 41 in the REN group, and no conversion to laparotomy. Most tumors were located in the head of pancreas (71.9 %). The tumor diameter (3.1 vs. 1.9 cm) was larger, and more cystic tumors (92.7 % vs. 56.4 %) and more tumors involving the MPD (34.1 % vs. 3.6 %) were observed in the REN group. MPD support tube insertion was performed in 15 cases, with 11 in the REN group and 4 in the LEN group. The incidence of biochemical and grade B postoperative pancreatic fistula (POPF) was both 46.9 %, and no grade C POPF occurred. Among the 45 patients with grade B POPF, 28 cases (62.2 %) were due to carrying drainage tube >3 weeks without additional treatment, and only 4 cases required invasive treatment. For patients with MPD support tube implantation (n = 15), support tube fall-offs were observed in 12 cases, 2 patients had MPD dilatation, and no MPD stricture, stone formation or pancreatic atrophy was observed during follow-up.

Conclusions

The incidence of POPF was high but still controllable without serious complications after minimally invasive enucleation. The MPD is no longer a restricted area, and the robotic system has advantages in handling complex enucleations.

Co-occurring IPMN and pancreatic cancer: the same or different? An overview from histology to molecular pathology

Intraductal papillary mucinous neoplasm (IPMN) of the pancreas is one of the most well-established precursors of pancreatic cancer. Its progression to acquire invasiveness is a complex process, based on the accumulation of morphological and genetic alterations. Recent advances in DNA sequencing also showed that co-occurring IPMNs and pancreatic cancers could be totally independent, further complicating our understanding of this complex scenario. The distinction between IPMN and related pancreatic cancer vs IPMN and co-occurring-but not related-pancreatic cancer is a challenging task in routine diagnostic activity, but may have important implications for precision oncology. Of note, recent multiregional sequencing-based studies focused not only on IPMN multi-step tumourigenesis, but also on the divergent intratumoural heterogeneity of this neoplasm. Globally considered, there are three different situations in which co-occurring IPMNs and invasive carcinomas can be found in the same pancreata, indicated with different terminologies: (1) IPMN-associated carcinoma: this definition indicates a carcinoma arising from an IPMN and can be also defined as IPMN-derived carcinoma, sequential or likely related; (2) independent IPMN and invasive carcinoma: the two lesions are not related, and this situation is defined as concomitant, de novo or likely independent; (3) branch-off pathway, where an invasive carcinoma and an adjacent IPMN develop divergently in a forked fashion from a common ancestral clone. In this review, we aim at clarifying the most important nomenclature/definitions of these different situations, also providing an overview of the molecular state-of-the-art and of the clinical implications of this complex landscape.

Pancreatic ductal adenocarcinomas concomitant with intraductal papillary mucinous neoplasms of the pancreas: A investigation of those clinicopathological features by analyzing 48 patients who underwent surgery for those lesions

BACKGROUND

Differences between pancreatic ductal adenocarcinomas (PDACs) concomitant with intraductal papillary mucinous neoplasm (IPMN) (C-PDACs), those without IPMN (NC-PDACs) and invasive cancers derived from IPMN (IC-Ds) have not been fully clarified.

METHODS

Forty-eight patients with C-PDAC were included to investigate the differences in 1) clinicopathological features and 2) post-operative courses among the three invasive cancer groups.

RESULTS

1) Characteristics of C-PDACs were mostly similar to those of NC-PDACs; whereas, between C-PDACs and IC-Ds, the rate of mucinous carcinoma (2%/25%, p = 0.003) and pathological stage (IA, 15%/36%, p = 0.033; III, 31%/4%, p = 0.015) significantly differed. Most C-PDACs coexisted with small, multifocal IPMNs without mural nodules. 2) Cumulative 5-year recurrence-free survival (RFS) rate related to extra-pancreatic recurrence was significantly worse in C-PDACs than in IC-Ds (35%/69%, p = 0.008) and was not significantly different between C-PDACs and NC-PDACs (35%/18%). This related to intra-pancreatic recurrence tended to be poor in the order of IC-Ds, C-PDACs, and NC-PDACs (69%/82%/93%).

CONCLUSIONS

Because characteristics of IPMNs remarkably differed between C-PDACs and IC-Ds, another algorithm specific to the early detection of C-PDACs is necessary. Appropriate post-operative managements according to the two types of recurrences may contribute to the improvement in the prognoses of C-PDACs/IC-Ds.

Propensity Score Matching Analysis of the Safety of Completion Total Pancreatectomy for Remnant Pancreatic Tumors Versus that of Initial Total Pancreatectomy for Primary Pancreatic Tumors

BACKGROUND

The safety and feasibility of completion total pancreatectomy (TP) for remnant pancreatic neoplasms remain controversial and are rarely compared with that of initial TP. Thus, we aimed to compare the safety of these two procedures inducing a pancreatic state.

METHODS

Patients who underwent TP for pancreatic neoplasms between 2006 and 2018 at our institution were included in this study. Tumor pathologies were classified into three subgroups according to survival curves. We used 1:1 propensity score matching (PSM) to analyze age, sex, Charlson Comorbidity Index, and tumor stage. Finally, we analyzed the primary outcome Clavien-Dindo classification (CDC) grade, risks of other safety-related outcomes, and the survival rate of patients with invasive cancer.

RESULTS

Of 54 patients, 16 underwent completion TP (29.6%) and 38 (70.4%) underwent initial TP. Before PSM analysis, age and Charlson Comorbidity Index were significantly higher, and T category and stage were significantly lower for the completion TP group. Upon PSM analysis, these two groups were equivalent in CDC grade [initial TP vs. completion TP: 71.4% (10/14) vs. 78.6% (11/14); p = 0.678] and other safety-related outcomes. Additionally, while the overall survival and recurrence-free survival of patients with invasive cancer were not significantly different between these two groups, the T category and stage tended to be remarkably severe in the initial TP group.

CONCLUSIONS

PSM analysis for prognostic factors showed that completion TP and initial TP have similar safety-related outcomes that can be used as a decision-making reference in the surgery of pancreatic tumors.

Presence of low-grade IPMN at the pancreatic transection margin does not have prognostic significance after resection of IPMN-associated pancreatic adenocarcinoma

INTRODUCTION

Resection margin status is a well-established prognosticator in pancreatic cancer. The prognostic impact of IPMN dysplasia at the pancreatic transection margin in IPMN-associated carcinoma (IPMN-Ca) remains unclear, hence institutional practices on additional resections vary.

METHODS

Patients undergoing partial pancreatectomy or attempted partial pancreatectomy converted to total pancreatectomy for IPMN-Ca between 04/2002 and 12/2018 were identified. Final pathology of the definitive pancreatic transection margin was identified. The association between the presence of IPMN dysplasia at the margin and overall survival (OS) was assessed.

RESULTS

Of 302 patients with IPMN-Ca, 181 (59.9%) patients received partial pancreatoduodenectomy, 61 (20.2%) distal pancreatectomy, and 60 (19.9%) were converted to total pancreatectomy. Median OS was 98.6 months in R0 (≥1 mm), 39.3 months in R1 (<1 mm), and 22.0 months in R1(direct) resected patients, respectively (p < 0.0001). No IPMN dysplasia at the definitive margin was present in 103 (34.1%), low-grade in 131 (43.4%), and high-grade/R1 in 8 (2.6%) patients. Low-grade dysplasia or total pancreatectomy were not associated with shorter OS compared to dysplasia-free margin across the entire cohort. Sensitivity analyses confirmed a lack of prognostic relevance of low-grade IPMN dysplasia at the pancreatic margin in R0 resected IPMN-Ca and in R0 resected UICC stage IA/IB IPMN-Ca.

CONCLUSIONS

Low-grade IPMN at the transection margin is not associated with shorter overall survival after partial pancreatectomy for IPMN-Ca. Additional resections for low-grade dysplasia, up to total pancreatectomy do not result in a survival benefit and should be omitted. Due to limited sample size, high-grade dysplasia could not be analyzed.

Long-term outcomes of patients with multifocal intraductal papillary mucinous neoplasm following pancreatectomy

BACKGROUND

The decision to perform surgery is complicated by the presence of multifocal (MF) intraductal papillary mucinous neoplasms (IPMNs), which are characterized by two or more cysts located in different areas of the pancreas.

OBJECTIVES

We aimed to establish a suitable treatment strategy and surgical indications in patients with MF-IPMNs.

METHODS

This single-center retrospective study included patients with IPMNs who underwent pancreatic resection from 2006 to 2020. Patients with distant metastasis and patients with IPMNs of the main pancreatic duct were excluded from the analysis.

RESULTS

After excluding 22 patients, 194 patients were included. One hundred thirteen patients (58.2%) had unifocal IPMNs, while 81 patients (41.8%) had MF-IPMNs. There were no significant differences in the 5-year disease-specific survival (DSS) rate (92.3% vs. 92.4%, p = 0.976) and the 5-year disease-free survival rate (88.6% vs. 86.5%, p = 0.461). The multivariate analysis identified high-risk stigmata, invasive carcinoma, and lymph node metastasis as independent predictors of DSS. The presence of cystic lesions in the pancreatic remnant was not a predictor of survival. Even in the MF-IPMN group, there were no significant differences in DSS when stratified by procedure (total pancreatectomy vs. segmental pancreatectomy, p = 0.268) or presence of cystic lesions in the pancreatic remnant (p = 0.476). The multivariate analysis identified lymph node metastasis as an independent predictor of DSS in the MF-IPMN group.

CONCLUSIONS

In patients with MF-IPMNs, each cyst should be evaluated individually for the presence of features associated with malignancy.

Can we predict the progression of premalignant pancreatic cystic tumors to ductal adenocarcinoma?

Pancreatic ductal adenocarcinoma (PDAC) is the most prevalent malignant pancreatic tumor. Few studies have shown how often PDACs arise from cystic precursor lesions. This special report aims to summarize the evidence on the progression of precancerous lesions to PDAC. A review of the literature found four studies that discussed pancreatic intraepithelial lesions (PanINs), three that discussed mucinous cystic neoplasms (MCN) and five that discussed intraductal papillary neoplasms (IPMNs). PanINs were the most common precursors lesion, with approximately 80% of PDACs originating from this lesion. The lack of evidence characterizing the features of PDAC precursor cystic lesions potentially leads to a subset of patients undergoing surgery unnecessarily. Advancements in molecular techniques could allow the study of cystic lesions at a genetic level, leading to more personalized management.

Prediction of Recurrence Pattern of Pancreatic Cancer Post-Pancreatic Surgery Using Histology-Based Supervised Machine Learning Algorithms: A Single-Center Retrospective Study

BACKGROUND

Patients with pancreatic cancer (PC) have poor prognosis and a high incidence of recurrence. Since further treatment is applicable for specific recurrent events, it is important to predict recurrence patterns after surgery. This study aimed to identify and predict early and late recurrence patterns of PC using a histology-based machine learning model.

PATIENTS AND METHODS

Patients who underwent upfront curative surgery for PC between 2001 and 2014 were included. The timing of recurrence and prognosis of each first recurrence site were examined. A histology-based supervised machine learning method, which combined convolutional neural networks and random forest, was used to predict the recurrence and respective sites of metastasis. Accuracy was evaluated using area under the receiver operating characteristic curve (AUC).

RESULTS

In total, 524 patients were included. Recurrence in the liver accounted for 47.8% of all recurrence events in the first year after surgery. Meanwhile, recurrence in the lung occurred later and could become apparent more than 5 years post-surgery, with indications for further surgery. In terms of substantial distant organ metastases, liver and lung metastases were identified as representative early and late recurrence events. The predictive AUCs of the machine learning model for training and test data were 1.000 and 0.861, respectively, and for predicting nonrecurrence were 1.000 for both.

CONCLUSIONS

We identified the liver and lung as early and late recurrence sites, which could be distinguished with high probability using a machine learning model. Prediction of recurrence sites using this model may be useful for further treatment of patients with PC.

Laparoscopic distal pancreatectomy for intraductal papillary mucinous neoplasm-associated pancreatic cancer: A case report

Introduction and importance

Intraductal papillary mucinous neoplasm (IPMN) of the pancreas is often found incidentally during examination for other diseases. In addition to the risk of malignant transformation, patients with IPMN are at risk of developing pancreatic cancer. We report a case of pancreatic tail cancer that developed separately from a preexisting IPMN after minimally invasive esophagectomy for cancer of the esophagogastric junction and was resected successfully by laparoscopic distal pancreatectomy.

Case presentation

A 72-year-old man underwent thoracoscopic and laparoscopic esophagectomy for esophagogastric junction cancer. He had undergone surgery for ascending colon cancer 20 years ago. At that time, IPMN was confirmed in the pancreatic body by a preoperative examination. Computed tomography was regularly performed for postoperative work-up and follow-up of the IPMN, and a solid lesion with cystic components was detected in the pancreatic tail 9 months after the operation. On detailed examination, pancreatic ductal adenocarcinoma concomitant with IPMN, accompanied by a retention cyst, was considered. Laparoscopic distal pancreatectomy was successfully performed after neoadjuvant chemotherapy. Pathological diagnosis of the lesion in the pancreatic tail was of an invasive intraductal papillary mucinous carcinoma (ypT3ypN0yM0 ypStageIIA).

Clinical discussion

If an IPMN is detected during preoperative examination for malignancies of other organs, careful follow-up is necessary due to the high risk of pancreatic cancer development. Furthermore, initial operation with minimally invasive surgery may reduce adhesion and facilitate subsequent surgeries.

Conclusion

We have provided evidence that supports the importance of a careful follow-up of IPMNs, even if they are low risk.

•

Intraductal papillary mucinous neoplasm of the pancreas is found incidentally.

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A pre-existing neoplasm led to pancreatic tail cancer in one patient.

•

Due to careful follow-up of the neoplasm, the secondary cancer was detected rapidly.

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It was resected successfully by laparoscopic distal pancreatectomy.

•

Careful follow is necessary if this neoplasm is detected.

[Intraductal neoplasms of the pancreas]

The latest WHO classification of tumors of the digestive system (2019) has introduced new concepts for the stratification of intraductal neoplasms of the pancreas, mostly based on molecular genetics and malignant potential. Among them, pancreatic intraepithelial neoplasias (PanINs) and intraductal papillary mucinous neoplasms (IPMN) are both precursors of pancreatic ductal adenocarcinoma, whereas intraductal oncocytic papillary neoplasms (IOPN) and intraductal tubulopapillary neoplasms (ITPN) are usually associated with less aggressive subtypes of pancreatic cancer and therefore have a much better prognosis. Hence, it is of utmost importance to correctly classify these lesions and to distinguish them from each other as well as from other nonductal types of neoplasms, which can rarely display an intraductal growth, such as neuroendocrine tumors and acinar cell carcinomas. PanIN are microscopic lesions with limited clinical significance. In contrast, all other intraductal neoplasms can be identified as cystic processes and/or solid tumors by means of imaging, thereby setting an indication for a potential surgical resection. This review presents diagnostically relevant aspects of intraductal neoplasms of the pancreas, which are instrumental for the discussion within interdisciplinary tumor boards (resection vs. watch-and-wait strategies) as well as to determine the extent of resection intraoperatively.

Partial pancreatic tail preserving subtotal pancreatectomy for pancreatic cancer: Improving glycemic control and quality of life without compromising oncological outcomes

BACKGROUND

Total pancreatectomy (TP) is usually considered a therapeutic option for pancreatic cancer in which Whipple surgery and distal pancreatectomy are undesirable, but brittle diabetes and poor quality of life (QoL) remain major concerns. A subset of patients who underwent TP even died due to severe hypoglycemia. For pancreatic cancer involving the pancreatic head and proximal body but without invasion to the pancreatic tail, we performed partial pancreatic tail preserving subtotal pancreatectomy (PPTP-SP) in selected patients, in order to improve postoperative glycemic control and QoL without compromising oncological outcomes.

AIM

To evaluate the efficacy of PPTP-SP for patients with pancreatic cancer.

METHODS

We retrospectively reviewed 56 patients with pancreatic ductal adenocarcinoma who underwent PPTP-SP (n = 18) or TP (n = 38) at our institution from May 2014 to January 2019. Clinical outcomes were compared between the two groups, with an emphasis on oncological outcomes, postoperative glycemic control, and QoL. QoL was evaluated using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30 and EORTC PAN26). All patients were followed until May 2019 or until death.

RESULTS

A total of 56 consecutive patients were enrolled in this study. Perioperative outcomes, recurrence-free survival, and overall survival were comparable between the two groups. No patients in the PPTP-SP group developed cancer recurrence in the pancreatic tail stump or splenic hilum, or a clinical pancreatic fistula. Patients who underwent PPTP-SP had significantly better glycemic control, based on their higher rate of insulin-independence (P = 0.014), lower hemoglobin A1c (HbA1c) level (P = 0.046), lower daily insulin dosage (P < 0.001), and less frequent hypoglycemic episodes (P < 0.001). Global health was similar in the two groups, but patients who underwent PPTP-SP had better functional status (P = 0.036), milder symptoms (P = 0.013), less severe diet restriction (P = 0.011), and higher confidence regarding future life (P = 0.035).

CONCLUSION

For pancreatic cancer involving the pancreatic head and proximal body, PPTP-SP achieves perioperative and oncological outcomes comparable to TP in selected patients while significantly improving long-term glycemic control and QoL.

Chronic inflammatory changes and oxidative stress in the background of "pancreatic ductal adenocarcinoma concomitant with intraductal papillary mucinous neoplasm"

Cases of "pancreatic ductal adenocarcinoma (PDAC) concomitant with intraductal papillary mucinous neoplasm" (IPMN) have multiple PDAC lesions more frequently than cases of "PDAC without IPMN". However, the mechanism of carcinogenesis in this former disease category remains unknown. The main objective of this work was thus to investigate the effects of chronic inflammation on carcinogenesis in PDAC cases. We selected 31 "PDAC concomitant with IPMN" patients and 58 "PDAC without IPMN" patients and pathologically evaluated their background pancreatic parenchyma. Fibrosis and inflammation scores of background pancreas were higher in "PDAC concomitant with IPMN" than in "PDAC without IPMN" (P < 0.0001 and P < 0.0001, respectively), whereas the fatty infiltration score of background pancreas was high in "PDAC without IPMN" (P = 0.0024). Immunohistochemically, the expression of 8-hydroxy-2'-deoxyguanosine (8-OHDG), an oxidative stress marker, in the background pancreas was high in "PDAC concomitant with IPMN" compared with that in "PDAC without IPMN" (P < 0.0001). Chronic inflammation activates oxidative stress in tissue throughout the pancreas and probably confers susceptibility to tumorigenesis in "PDAC concomitant with IPMN".

Robotic pancreatectomy for intraductal papillary mucinous neoplasm of the pancreas: A large-scale study

BACKGROUND

Intraductal papillary mucinous neoplasm (IPMN) of the pancreas is a mucin-producing tumor that develops from the epithelial lining of the main pancreatic duct or branch pancreatic ducts. Here, we assessed the feasibility and safety of various robotic pancreatectomy approaches to treating IPMN, and short- and long-term outcomes of robotic IPMN resection.

METHODS

Data from patients who underwent robotic pancreatectomy for IPMN between 2012 and 2019 at our hospital were retrospectively analyzed. The survival outcomes for patients were compared using the Kaplan-Meier method and Cox regression analysis.

RESULTS

Of the 174 patients who underwent robotic pancreatectomy, 120 and 54 patients had benign or malignant tumors, respectively. Patients with malignant IPMN had lost more weight in the 6 months prior to surgery (P = .008), and a higher serum level of CA19-9 (P < .001) and CEA (P < .001). Postoperative pancreatic or biliary fistula occurred in 17 or 6 patients overall, respectively. The pathology of the IPMN (P = .030), tumor diameter (P = .016), mural nodule (P = .023), tumor capsule (P = .003) and CA19-9 (P = .024) values were all independent risk factors for survival. The median OS time after surgical resection for the malignant IPMN group was 29.0 months (range, 21.6-36.4). The OS was significantly different in patients with IPMN according to their different pathology, tumor capsule, mural nodule group, CA19-9 level, or tumor diameter.

CONCLUSIONS

This large-scale survey of 174 patients indicated that various robotic pancreatectomy approaches were feasible and safe for IPMN. Patients had an acceptable prognosis, indicating that robotic pancreatectomy represents a feasible potential therapeutic strategy for IPMN.

Minimally invasive surgery for pancreatic cancer

Pancreatic cancer is the most lethal malignancy of the digestive organs. Although pancreatic resection is essential to radically cure this refractory disease, the multi-organ resection involved, as well as sequelae such as glucose tolerance insufficiency and severe complications impose a heavy burden on these patients. Since the late twentieth century, minimally invasive surgery has become more popular for the surgical management of digestive disease and pancreatic cancer. Minimally invasive pancreatic resection (MIPR), including pancreaticoduodenectomy and distal pancreatectomy, is now a treatment option for pancreatic cancer. Some evidence suggests that MIPR for pancreatic cancer provides comparable oncological outcomes to open surgery, with some advantages in perioperative outcomes. However, as this evidence is retrospective, prospective investigations, including randomized controlled trials, are necessary. Because neoadjuvant therapy for resectable or borderline-resectable pancreatic cancer and conversion surgery for initially unresectable pancreatic cancer has become more common, the feasibility of MIPR after neoadjuvant therapy or as conversion surgery requires further assessment. It is expected that progress in surgical techniques and devices, as well as the standardization of surgical procedures and widespread educational programs will improve the outcomes of MIPR.

Is remnant pancreatic cancer after pancreatic resection more frequent in early-stage pancreatic cancer than in advanced-stage cancer?

AIM

As the prognosis of patients who undergo resection for pancreatic cancer has improved, reports of remnant pancreatic cancer after pancreatic cancer resection have been increasing. Previous studies regarding early-stage pancreatic cancer showed a high incidence of remnant pancreatic cancer in these patients. The aim of this study was to investigate the incidence of remnant pancreatic cancer according to the degree of progression of the initial pancreatic cancer.

METHODS

Patients who underwent partial pancreatic resection for primary pancreatic cancer were retrospectively reviewed and divided into an early-stage group and an advanced-stage group according to the stage of the initial cancer. Patient characteristics and long-term outcomes, including development of remnant pancreatic cancer, were compared between the two groups.

RESULTS

This study included 321 patients who underwent partial pancreatectomy for pancreatic cancer; 32 patients in the early-stage group and 289 patients in the advanced-stage group. Remnant pancreatic cancer developed in 19 patients (5.9%); seven patients (21.9%) in the early-stage group and 12 patients (4.5%) in the advanced-stage group. The cumulative incidence of remnant pancreatic cancer according to the Kaplan-Meier method was comparable between the two groups (5-year cumulative incidence: 20.6% vs 9.9%, early-stage group vs advanced-stage group; P = .1827).

CONCLUSION

Our results suggested that the potential for developing remnant pancreatic cancer was comparable between the early-stage and the advanced-stage groups. Therefore, the incidence of remnant pancreatic cancer may increase along with improved pancreatic cancer treatment.

High-risk lesions in the remnant pancreas: fate of the remnant pancreas after pancreatic resection for pancreatic cancer and intraductal papillary mucinous neoplasms

Progress in diagnostic modalities, surgical procedures, and multidisciplinary treatment for pancreatic diseases has increased the number of long-term survivors after pancreatic resection. Several reports have focused on high-risk lesions (HRLs), including high-grade pancreatic intraepithelial neoplasia (PanIN), pancreatic ductal adenocarcinoma, high-grade intraductal papillary mucinous neoplasm (IPMN), and IPMN with an associated invasive carcinoma, in the remnant pancreas after partial pancreatic resection for pancreatic cancer or IPMN. The etiology of HRLs in the remnant pancreas is thought to be either isolated local recurrence of the initial lesion in the remnant pancreas or a newly developed primary lesion. Although it is difficult to distinguish between local recurrence and a new primary lesion, comparison of genetic alterations between two lesions may help with this distinction. Early detection of HRLs in the remnant pancreas may improve the prognosis of patients, and several investigators have proposed predictive factors for HRLs in the remnant pancreas after partial pancreatic resection for pancreatic cancer or IPMN. The reported short- and long-term outcomes of surgical resection of HRLs in the remnant pancreas are relatively favorable. Life-long surveillance of the remnant pancreas is recommended after partial pancreatic resection for pancreatic cancer or IPMN.