Resectable invasive IPMN versus sporadic pancreatic adenocarcinoma of the head of the pancreas: Should these two different diseases receive the same treatment? A matched comparison study of the French Surgical Association (AFC)

Is chemotherapy beneficial? A retrospective study of chemotherapy in patients with invasive intraductal papillary-mucinous carcinoma

Background and aim

Whether chemotherapy can improve the prognosis of invasive intraductal papillary-mucinous carcinoma (IPMC) still remains unclear. The aim of this study is to observe the difference in survival time of patients with invasive IPMC receiving or not receiving chemotherapy.

Methods

117 patients with invasive IPMC were included in The Surveillance, Epidemiology, and End Results (SEER) database. These patients were subsequently divided into two subgroups according to whether they received chemotherapy or not: the non-chemotherapy group (patients who did not receivechemotherapy, N = 58), the chemotherapy group (patients who received chemotherapy, N = 59). The overall survival (OS) and cancer specific survival (CSS) of two treatment groups were evaluated.

Results

Before adjusting for pathology grade, the Kaplan-Meier analysis showed that the difference of survival time is not significant between non-chemotherapy group and chemotherapy group (P > 0.05), but the land-mark analysis showed that short-term death risk of the chemotherapy group is significantly lower than non-chemotherapy group (P < 0.05). After adjust the pathology grade, survival time of the chemotherapy group is significantly longer than non-chemotherapy group (P < 0.05). Univariate and multivariate Cox regression showed that chemotherapy was an independent prognostic protective factor for invasive IPMC (P < 0.05). Land-mark analysis showed that short-term death risk of the chemotherapy group is significantly lower than non-chemotherapy group in N1-N2 subgroup (P < 0.05).

Conclusion

Chemotherapy is an independent protective factor IPMC, especially reducing the risk of short-term death for IPMC patients with lymph node metastasis.

Is multidisciplinary treatment effective for invasive intraductal papillary mucinous carcinoma?

Background

Surgical resection is standard treatment for invasive intraductal papillary mucinous carcinoma (IPMC); however, impact of multidisciplinary treatment on survival including postoperative adjuvant therapy (AT), neoadjuvant therapy (NAT), and treatment for recurrent lesions is unclear. We investigated the effectiveness of multidisciplinary treatment in prolonging survival of patients with invasive IPMC.

Methods

This retrospective multi-institutional study included 1183 patients with invasive IPMC undergoing surgery at 40 academic institutions. We analyzed the effects of AT, NAT, and treatment for recurrence on survival of patients with invasive IPMC.

Results

Completion of the planned postoperative AT for 6 months improved the overall survival (OS), disease-specific survival (DSS), and recurrence-free survival (RFS) of patients with stage IIB and stage III resected invasive IPMC, elevated preoperative carbohydrate antigen 19-9 level, lymphovascular invasion, perineural invasion, serosal invasion, and lymph node metastasis on un-matched and matched analyses. Of the patients with borderline resectable (BR) invasive IPMC, the OS (p = 0.001), DSS (p = 0.001), and RFS (p = 0.001) of patients undergoing NAT was longer than that of those without on the matched analysis. Of the 484 invasive IPMC patients (40.9%) who developed recurrence after surgery, the OS of 365 patients who received any treatment for recurrence was longer than that of those without treatment (40.6 vs. 22.4 months, p < 0.001).

Conclusion

Postoperative AT might benefit selected patients with invasive IPMC, especially those at high risk of poor survival. NAT might improve the survivability of BR invasive IPMC. Any treatment for recurrence after surgery for invasive IPMC might improve survival.

A narrative review on rare types of pancreatic cancer: should they be treated as pancreatic ductal adenocarcinomas?

Pancreatic cancer is one of the deadliest malignancies in humans and it is expected to play a bigger part in cancer burden in the years to come. Pancreatic ductal adenocarcinoma (PDAC) represents 85% of all primary pancreatic malignancies. Recently, much attention has been given to PDAC, with significant advances in the understanding of the mechanisms underpinning disease initiation and progression, along with noticeable improvements in overall survival in both localized and metastatic settings. However, given their rarity, rare histological subtypes of pancreatic cancer have been underappreciated and are frequently treated as PDAC, even though they might present non-overlapping molecular alterations and clinical behavior. While some of these rare histological subtypes are true variants of PDAC that should be treated likewise, others represent separate clinicopathological entities, warranting a different therapeutic approach. In this review, we highlight clinical, pathological, and molecular aspects of rare histological types of pancreatic cancer, along with the currently available data to guide treatment decisions.

Outcomes of Neoadjuvant Chemotherapy for Invasive Intraductal Papillary Mucinous Neoplasm Compared with de Novo Pancreatic Adenocarcinoma

BACKGROUND

The management of invasive intraductal papillary mucinous cystic neoplasm (I-IPMN) does not differ from de novo pancreatic ductal adenocarcinoma (PDAC); however, I-IPMNs are debated to have better prognosis. Despite being managed similarly to PDAC, no data are available on the response of I-IPMN to neoadjuvant chemotherapy.

METHODS

All patients undergoing pancreatic resection for a pancreatic adenocarcinoma from 2011 to 2022 were included. The PDAC and I-IPMN cohorts were compared to evaluate response to neoadjuvant therapy (NAT) and overall survival (OS).

RESULTS

This study included 1052 PDAC patients and 105 I-IPMN patients. NAT was performed in 25% of I-IPMN patients and 65% of PDAC patients. I-IPMN showed a similar pattern of pathological response to NAT compared with PDAC (p = 0.231). Furthermore, positron emission tomography (PET) response (71% vs. 61%; p = 0.447), CA19.9 normalization (85% vs. 76%, p = 0.290), and radiological response (32% vs. 37%, p = 0.628) were comparable between I-IPMN and PDAC. A significantly higher OS and disease-free survival (DFS) of I-IPMN was denoted by Kaplan-Meier analysis, with a p-value of < 0.001 in both plots. In a multivariate analysis, I-IPMN histology was independently associated with lower risk of recurrence and death.

CONCLUSIONS

I-IPMN patients have a longer OS and DFS after surgical treatment when compared with PDAC patients. The more favorable oncologic outcome of I-IPMNs does not seem to be related to early detection, as I-IPMN histological subclass is independently associated with a lower risk of disease recurrence. Moreover, neoadjuvant effect on I-IPMN was non-inferior to PDAC in terms of pathological, CA19.9, PET, and radiological response and thus can be considered in selected patients.

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.

Incidence of Postoperative Complications Following Pancreatectomy for Pancreatic Cystic Lesions or Pancreatic Cancer

BACKGROUND

In contrast to pancreatic ductal adenocarcinoma (PDAC), the risks of pancreatectomy for mucinous pancreatic cysts (MCs) are balanced against the putative goal of removing potentially malignant tumors. Despite undergoing similar operations, different rates of perioperative complications and morbidity between MC and PDAC patient populations may affect recommendations for resection. We therefore sought to compare the rates of postoperative complications between patients undergoing pancreatectomies for MCs or PDAC.

METHODS

A prospectively maintained institutional database was used to identify patients who underwent surgical resection for MCs or PDAC from July 2011 to August 2019. Patient demographics, complications, and perioperative data were compared between groups.

RESULTS

A total of 103 patients underwent surgical resection for MCs and 428 patients underwent resection for PDAC. Combined major 90-day postoperative complications were similar between MC and PDAC patients undergoing pancreaticoduodenectomy (PD, 32.5% vs. 20.0%, p = 0.068) or distal pancreatectomy (DP, 30.2% vs. 20.5%, p = 0.172). The most frequent complications were postoperative pancreatic fistula (POPF), abscess, and postoperative bleeding. The incidence of 90-day ISGPS Grade B/C POPF was higher in cyst patients undergoing PD (17.5% vs. 4.1%, p = 0.003) but not DP (25.4% vs. 20.5%, p = 0.473). No significant differences in operative time or length of stay between MCs and PDAC cohorts were observed.

CONCLUSIONS

POPFs occur more frequently and at higher grades in patients undergoing PD for MCs than for PDAC and should inform patient selection. Accordingly, the perioperative management of MC patients undergoing PD should emphasize POPF risk mitigation.

Outcome after surgery for invasive intraductal papillary mucinous neoplasia compared to conventional pancreatic ductal adenocarcinoma - A Swedish nationwide register-based study

BACKGROUND

The clinical importance of intraductal papillary mucinous neoplasm (IPMN) have increased last decades. Long-term survival after resection for invasive IPMN (inv-IPMN) compared to conventional pancreatic ductal adenocarcinoma (PDAC) is not thoroughly delineated.

OBJECTIVE

This study, based on the Swedish national pancreatic and periampullary cancer registry aims to elucidate the outcome after resection of inv-IPMN compared to PDAC.

METHODS

All patients ≥18 years of age resected for inv-IPMN and PDAC in Sweden between 2010 and 2019 were included. Clinicopathological variables were retrieved from the national registry. The effect on death was assessed in two multivariable Cox regression models, one for patients resected 2010-2015, one for patients resected 2016-2019. Median overall survival (OS) was estimated using the Kaplan-Meier method.

RESULTS

We included 1909 patients, 293 inv-IPMN and 1616 PDAC. The most important independent predictors of death in multivariable Cox regressions were CA19-9 levels, venous resection, tumour differentiation, as well as T-, N-, M-stage and surgical margin. Tumour type was an independent predictor for death in the 2016-2019 cohort, but not in the 2010-2015 cohort. In Kaplan-Meier survival analysis, inv-IPMN was associated with longer median OS in stage N0-1 and in stage M0 compared to PDAC. However, in stage T2-4 and stage N2 median OS was similar, and in stage M1 even shorter for inv-IPMN compared to PDAC.

CONCLUSION

In this population-based nationwide study, outcome after resected inv-IPMN compared to PDAC is more favourable in lower stages, and similar to worse in higher.

Survival comparison of invasive intraductal papillary mucinous neoplasm versus pancreatic ductal adenocarcinoma

BACKGROUND

The aim of this study was to assess the relevance of highlighting T1a invasive intraductal papillary mucinous carcinoma as a separate subcategory and to compare the tumor biology between invasive intraductal papillary mucinous carcinoma and pancreatic ductal adenocarcinoma.

METHODS

A total of 144 and 328 consecutive patients with intraductal papillary mucinous neoplasms and pancreatic ductal adenocarcinoma, respectively, were analyzed.

RESULTS

Patients with T1a invasive intraductal papillary mucinous carcinoma comprised 25% (11/44) of the overall subject population with invasive intraductal papillary mucinous carcinoma with 5-year disease-specific survival rate being 100%. None of the patients with pancreatic ductal adenocarcinoma were classified as having T1a disease. When patients with invasive intraductal papillary mucinous carcinoma and pancreatic ductal adenocarcinoma were compared after excluding patients with T1a invasive intraductal papillary mucinous carcinoma, the 5-year disease-specific survival rates were 63% vs 40% in node-negative status (P = .018); and they were 20% vs 13% in node-positive status (P = .385). Subsequent analyses revealed that this survival superiority was limited to patients without evidence of lymphatic invasion.

CONCLUSION

T1a invasive intraductal papillary mucinous carcinoma is a clinical entity specifically observed in patients with intraductal papillary mucinous carcinoma, but not in patients with pancreatic ductal adenocarcinoma, and is associated with excellent postoperative survival outcomes. In the survival comparison after exclusion of patients with T1a tumors, when the analysis was limited to patients without lymphatic invasion or lymph node metastasis, the disease-specific survival rate remained higher in patients with invasive intraductal papillary mucinous carcinoma compared with those with pancreatic ductal adenocarcinoma, and this difference was considered as being attributable to the intrinsic indolent biological behavior of invasive intraductal papillary mucinous carcinoma. However, this survival advantage was lost once lymphatic invasion occurred.

Adjuvant Chemotherapy in the Treatment of Intraductal Papillary Mucinous Neoplasms of the Pancreas: Systematic Review and Meta-Analysis

BACKGROUND

The present systematic review aimed to compare survival outcomes of invasive intraductal papillary mucinous neoplasms (IIPMNs) treated with adjuvant chemotherapy versus surgery alone and to identify pathologic features that may predict survival benefit from adjuvant chemotherapy.

METHOD

A systematic search of MEDLINE, PubMed, Scopus, and EMBASE was performed using the PRISMA framework. Studies comparing adjuvant chemotherapy and surgery alone for patients with IIPMNs were included. Primary endpoint was overall survival (OS). A narrative synthesis was performed to identify pathologic features that predicted survival benefits from adjuvant chemotherapy.

RESULTS

Eleven studies and 3393 patients with IIPMNs were included in the meta-analysis. Adjuvant chemotherapy significantly reduced the risk of death in the overall cohort (HR 0.57, 95% CI 0.38-0.87, p = 0.009) and node-positive patients (HR 0.29, 95% CI 0.13-0.64, p = 0.002). Weighted median survival difference between adjuvant chemotherapy and surgery alone in node-positive patients was 11.6 months (95% CI 3.83-19.38, p = 0.003) favouring chemotherapy. Adjuvant chemotherapy had no impact on OS in node-negative patients (HR 0.53, 95% CI 0.20-1.43, p = 0.209). High heterogeneity (I2 > 75%) was observed in pooled estimates of hazard ratios. Improved OS following adjuvant chemotherapy was reported for patients with stage III/IV disease, tumour size > 2 cm, node-positive status, grade 3 tumour differentiation, positive margin status, tubular carcinoma subtype, and presence of perineural or lymphovascular invasion.

CONCLUSION

Adjuvant chemotherapy was associated with improved OS in node-positive IIPMNs. However, the findings were limited by marked heterogeneity. Future large multicentre prospective studies are needed to confirm these findings and explore additional predictors of improved OS to guide patient selection for adjuvant chemotherapy.

A novel staging system and clinical predictive nomogram for more accurate staging and prognosis of malignant pancreatic intraductal papillary mucinous neoplasms: a population-based study

BACKGROUND

The current guidelines of the American Joint Committee on Cancer (AJCC) for the staging of exocrine pancreatic tumors seem inapplicable to malignant pancreatic intraductal papillary mucinous neoplasms (IPMN). Therefore, we aimed to improve the accuracy of clinical staging and prognosis for malignant IPMN by modifiing current AJCC system.

METHODS

We extracted data of 2001 patients with malignant IPMN from the Surveillance, Epidemiology, and End Results database between 2000 and 2016. Of these, 1401 patients were assigned to the primary cohort and 600 patients to the validation cohort.

RESULTS

In Kaplan-Meier analysis of the primary cohort, the current AJCC guidelines were unable to distinguish between certain tumor substages (IA and IB in the 7th, IB and IIA in the 8th). The modified system that we regrouped based on the median overall survival and hazard ratios, was superior in tumor stage classifications. Age > 70 years, tumors located in the body or tail, high-grade differentiated tumors, surgery, chemotherapy, and tumor, lymph node, and metastasis (TNM) stage were identified as independent predictive factors for overall survival. Compared to that of TNM-based systems, the concordance index of the clinical predictive nomogram significantly improved (0.819; 95% confidence interval, 0.805-0.833), with excellent area under the receiver operating characteristic curves (1-, 3-, and 5-year: 0.881, 0.889, and 0.879, respectively). The calibration curves also showed good agreement between prediction and actual observation. The analysis of treatment modalities revealed that surgery resulted in better survival for all resectable malignant IPMN. The analysis of chemotherapy data reveals its potential in improving the prognosis of treatment for patients with locally advanced or distant metastases.

CONCLUSIONS

Our modified staging system improves the distinction of tumor stages. The nomogram was a more accurate and clinically reliable tool for prognosis prediction of patients with malignant IPMN.

Outcome after resection for invasive intraductal papillary mucinous neoplasia is similar to conventional pancreatic ductal adenocarcinoma

BACKGROUND/OBJECTIVES

Resections for intraductal papillary mucinous neoplasm (IPMN) have increased last decades. Overall survival (OS) for conventional pancreatic ductal adenocarcinoma (PDAC) is well known but OS for invasive IPMN (inv-IPMN) is not as conclusive. This study aims to elucidate potential differences in clinicopathology and OS between these tumor types and to investigate if the raised number of resections have affected outcome.

METHODS

Consecutive patients ≥18 years of age resected for inv-IPMN and PDAC at Karolinska University Hospital between 2009 and 2018 were included. Clinicopathological variables were analyzed in multivariable regression models. Outcome was assessed calculating two-year OS, estimating OS using the Kaplan-Meier model and comparing survival functions with log-rank test.

RESULTS

513 patients were included, 122 with inv-IPMN and 391 with PDAC. During the study period both the proportion resected inv-IPMN and two-year OS, irrespective of tumor type, increased (2.5%-45%; p < 0.001 and 44%-57%; p = 0.005 respectively). In Kaplan-Meier survival analysis inv-IPMN had more favorable median OS (mOS) compared to PDAC (33.6 months vs 19.3 months, p = 0.001). However, in multivariable Cox Regression analysis, tumor type was not a predictor for death, but so were resection period, tumor subtype and N-stage (all p < 0.001).

CONCLUSION

In this large single center observational cohort study, inv-IPMN seemed to have favorable survival outcome compared to PDAC, but after adjusting for predictors for death this benefit vanished. The combination of a pronounced increase in resected inv-IPMN and a concurrent hazard abatement for death within 2 years during the study period proved to be a principal factor.

Role of postoperative adjuvant therapy in resected invasive intraductal papillary mucinous neoplasm of the pancreas: A multicenter external validation

BACKGROUND

Adjuvant therapy is beneficial in prolonging survival in patients with pancreatic ductal adenocarcinoma (PDAC). However, no clear guidelines are available on the oncologic effect of adjuvant therapy in resected invasive intraductal papillary mucinous neoplasms (inv-IPMN).

METHODS

In total, 551 patients with PDAC and 67 patients with inv-IPMN of the pancreas were reviewed. For external validation, 46 patients with inv-IPMN from six other Korean institutions were enrolled. Propensity score-matched analysis and stage-matched survival analysis were conducted.

RESULTS

The mean follow-up durations in the inv-IPMN and PDAC groups were 43.36 months (SD, 42.34 months) and 43.35 months (SD, 35.62 months), respectively. The 5-year overall survival (OS) was significantly better in the resected inv-IPMN group than in the PDAC group in the overall stage-matched analysis (P < .001). In the inv-IPMN cohort, OS was better in the surgery alone group (P = .042). In subgroup analysis, no significant survival difference was found between the adjuvant therapy and surgery alone groups according to the stage (stage I; P = .285, stage II or III; P = .077). Multicenter external validation did not show a better OS in the adjuvant therapy group (P = .531). On multivariable analysis, only perineural invasion (PNI) was identified as an adverse prognostic factor in resected inv-IPMN (HR 4.844; 95% CI 1.696-13.838, P = .003).

CONCLUSIONS

inv-IPMN has a more indolent course than PDAC. Current strategy of adjuvant therapy may not improve the OS in patients with resected inv-IPMN. Further investigations on the potential role of adjuvant therapy in inv-IPMN are mandatory.

Intraductal Papillary Mucinous Carcinoma Versus Conventional Pancreatic Ductal Adenocarcinoma: A Comprehensive Review of Clinical-Pathological Features, Outcomes, and Molecular Insights

Intraductal papillary mucinous neoplasms (IPMN) are common and one of the main precursor lesions of pancreatic ductal adenocarcinoma (PDAC). PDAC derived from an IPMN is called intraductal papillary mucinous carcinoma (IPMC) and defines a subgroup of patients with ill-defined specificities. As compared to conventional PDAC, IPMCs have been associated to clinical particularities and favorable pathological features, as well as debated outcomes. However, IPMNs and IPMCs include distinct subtypes of precursor (gastric, pancreato-biliary, intestinal) and invasive (tubular, colloid) lesions, also associated to specific characteristics. Notably, consistent data have shown intestinal IPMNs and associated colloid carcinomas, defining the “intestinal pathway”, to be associated with less aggressive features. Genomic specificities have also been uncovered, such as mutations of the GNAS gene, and recent data provide more insights into the mechanisms involved in IPMCs carcinogenesis. This review synthetizes available data on clinical-pathological features and outcomes associated with IPMCs and their subtypes. We also describe known genomic hallmarks of these lesions and summarize the latest data about molecular processes involved in IPMNs initiation and progression to IPMCs. Finally, potential implications for clinical practice and future research strategies are discussed.

Histopathological evaluation of resected intraductal papillary mucinous neoplasms reveals distinct patterns of invasion in associated carcinomas

Invasive intraductal papillary mucinous neoplasms (inv-IPMNs) have a better prognosis than regular pancreatic ductal adenocarcinoma (PDAC), but no association with status of surgical margins and microscopic infiltration patterns has previously been described. The aim of this study is to review patterns of invasion and the predictive value of clinical guidelines in terms of rates of resection of high-grade dysplasia (HGD) and cancer among intraductal papillary mucinous neoplasms (IPMNs). Consecutively, resected IPMNs between 2011 and 2017 were analyzed. Data were obtained from a prospectively maintained database. A total of 132 patients were identified. Out of these, 38 patients with inv-IPMNs, initially identified as solid lesions suspicious of cancer, were compared with a control group of 101 patients with ordinary PDAC. Lower rates of vascular invasion, perineural invasion, lymph node metastasis, advanced T stage, and R1 status were characteristic of the inv-IPMNs in addition to better overall survival (OS) for a low tumor stage. Furthermore, as novel findings, the PDACs presented with resection margin involvement of 3 or more positive margins (31.3% vs. 9.5%, p = 0.044), associated with poor OS. Of the patients presenting as pT3, the inv-IPMN less often invaded more than one extrapancreatic anatomical structure (40.1% vs. 63.9%, p = 0.03). Regarding the predictive value of clinical guidelines, the frequency of resected HGD in IPMNs with high-risk stigmata (n = 54) and IPMNs with worrisome features was 30.7%, and the frequency of invasive carcinoma was 5.7%. In conclusion, we report a low resection rate of high-risk IPMNs and present novel findings describing inv-IPMNs as a less infiltrative phenotype compared with regular PDAC.

Management of Incidental Pancreatic Cystic Lesions: Integrating Novel Diagnostic and Prognostic Factors With Current Clinical Guidelines

Owing to increased detection rates, the diagnosis and management of incidental pancreatic cysts has become a common predicament. Up to 13% of patients undergoing cross-sectional imaging studies for other indications are found to have pancreatic cystic lesions. Although most cystic lesions are benign, the malignant potential of several types of pancreatic cysts makes accurate classification vital to directing therapy. To this end, advances in the last decade led to better characterization of pancreatic cyst morphology and hence enhanced the ability to predict underlying histopathology, and biological behavior. Although accurate classification remains a challenge, the utilization of complementary diagnostic tools is the optimal approach to dictate management. The following review includes a description of pancreatic cysts, a critical review of current and emerging diagnostic techniques and a review of recent guidelines in the management of incidental pancreatic cysts.

Evaluation of preoperative prognostic factors in patients with resectable invasive intraductal papillary mucinous carcinoma

BACKGROUND

Upfront surgery is the standard treatment for resectable invasive intraductal papillary mucinous carcinoma; however, recurrence is common. Therefore, we investigated the recurrence, surgical outcome, and preoperative prognostic factors for recurrence in patients with resectable invasive intraductal papillary mucinous carcinoma.

METHODS

We analyzed 111 patients who underwent upfront surgery for resectable invasive intraductal papillary mucinous carcinoma between 2000 and 2017 and evaluated the relationship among clinicopathologic factors, recurrence, and outcomes.

RESULTS

The 5-year recurrence-free survival and disease-specific survival rates were 61% and 74%, respectively. The median time to recurrence was 1.1 years. In multivariate analysis, carbohydrate antigen 19-9 ≥83 U/mL (hazard ratio: 2.8 and 3.1), tumor size ≥2.2 cm (hazard ratio: 3.5 and 4.7), and pathologic tubular adenocarcinoma grade 2 (hazard ratio: 3.1 and 5.2) were risk factors for a shorter recurrence-free survival and disease-specific survival, respectively. Lymph node metastasis (hazard ratio: 3.9) was also a risk factor for a shorter disease-specific survival. When examining outcomes according to preoperatively measurable factors (carbohydrate antigen 19-9 ≥83 U/mL and tumor size ≥2.2 cm), the 5-year recurrence rates in patients with none (n = 47), 1 (n = 46), and both (n = 18) risk factors were 17%, 48%, and 78%, respectively. Five-year disease-specific survival rates in patients with none, 1, and both preoperative risk factors were 95%, 69%, and 31%, respectively.

CONCLUSION

Carbohydrate antigen 19-9 ≥83 U/mL and tumor size ≥2.2 cm were independent preoperative risk factors for poor outcomes in patients with resectable invasive intraductal papillary mucinous carcinoma.

Successful treatment with conversion surgery following chemoradiotherapy for unresectable invasive intraductal papillary mucinous neoplasm

INTRODUCTION

Recent advances in chemotherapy and chemoradiotherapy (CRT) have enabled the use of conversion surgery in selected patients with initially unresectable pancreatic duct adenocarcinoma after a favorable response to preoperative treatment. However, conversion surgery for invasive intraductal papillary mucinous neoplasm (IPMN) has not been reported.

CASE REPORT

A 63-year-old man was referred to our hospital for invasive IPMN treatment. Computed tomography revealed a multilocular tumor of 7.2 × 5.8 cm in diameter, which surrounded approximately 180° of the superior mesenteric artery and totally occluded the superior mesenteric vein (SMV). He was diagnosed with unresectable invasive IPMN. CRT was performed using four cycles of S-1 (100 mg/day) based on body surface area for 14 days every 3 weeks plus gemcitabine 1,000 mg/m² on days 8 and 15 with concurrent radiotherapy (50.4 Gy in 28 fractions). Response to chemotherapy revealed partial response according to the Response Evaluation Criteria in Solid Tumors; subsequently, subtotal stomach-preserving pancreaticoduodenectomy with SMV resection was performed. The postoperative course was uneventful. Four courses of adjuvant chemotherapy with TS-1 100 mg / day were administered postoperatively. At 5 years and 9 months after initiating treatment, the patient was alive without recurrence.

Recurrence patterns after surgical resection of intraductal papillary mucinous neoplasm (IPMN) of the pancreas; a multicenter, retrospective study of 1074 IPMN patients by the Japan Pancreas Society

BACKGROUND

Although there are numerous reports focusing on surgical indication for intraductal papillary mucinous neoplasm (IPMN), the recurrence patterns following surgery are less widely reported. To ascertain optimal treatment and postoperative surveillance for IPMN patients, we analyzed patterns and risk factors for recurrence after surgery for IPMN.

METHODS

This study is a retrospective, multi-institutional, observational study, including 1074 patients undergoing surgery for IPMN at 11 academic institutions. We analyzed the risk factors for recurrence after classifying postoperative recurrences into metachronous high-risk lesions (malignant progression of IPMN and/or metachronous pancreatic ductal adenocarcinoma) in the remnant pancreas and extra-pancreatic recurrence.

RESULTS

Of 1074 patients undergoing surgery for IPMN, 155 patients (14.4%) developed postoperative recurrence. We found that 34.3% of 70 high-risk lesions in the remnant pancreas occurred over 5 years after surgery, and survival of 36 patients undergoing second operation for high-risk lesions was better than that of 34 patients who did not (P = 0.04). We found four independent risk factors for metachronous high-risk lesions in remnant pancreas: symptoms [P = 0.005, hazard ratio (HR) 1.988], location of pancreatic body/tail (P < 0.001, HR 3.876), main duct size ≥ 10 mm (P = 0.021, HR 1.900), and high-grade dysplasia/invasive intraductal papillary mucinous carcinoma (IPMC) (P < 0.001, HR 3.204). Although six patients (0.7%) with low- or high-grade dysplasia IPMN developed extra-pancreatic recurrence, invasive IPMC was the strongest risk factor for extra-pancreatic recurrence (P < 0.001, HR 39.667).

CONCLUSION

We suggest that life-time continuous surveillance might be necessary for IPMN patients. Second surgery for metachronous high-risk lesions in remnant pancreas should be considered to improve survival.

Surgical strategy for intraductal papillary mucinous neoplasms of the pancreas

The current treatment strategy for intraductal papillary mucinous neoplasms (IPMNs), based on the international consensus guideline, has been accepted widely. However, reported outcomes after surgical resection for IPMN show that once the tumor progresses to invasive intraductal papillary mucinous carcinoma (IPMC), recurrence is not uncommon. The surgical treatment for IPMN is invasive and sometimes followed by complications. Therefore, the best timing for resection might be at the point when high-grade dysplasia (HGD) is evident. According to previous reports, main duct type IPMN has a high malignant potential and its surgical resection is universally accepted, whereas, the incidence of HGD/invasive IPMC in branch duct and mixed type IPMNs is thought to be lower. In addition to mural nodules and a dilated main pancreatic duct, cytology and measurement of the carcinoembryonic antigen level in the pancreatic juice might be useful to differentiate HGD/invasive IPMC from low-grade dysplasia. The nomogram proposed recently to predict the risk of HGD/invasive IPMC in IPMN patients might help surgeons decide on the best treatment strategy, depending on the patient's age and general condition. Second resection for high-risk lesions in the remnant pancreas might improve the survival of IPMN patients.

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.

Comparison of patients with invasive intraductal papillary mucinous carcinoma and invasive ductal carcinoma of the pancreas: a pathological type- and stage-matched analysis

Objective: We compared the pathological features and stage-matched outcomes of patients with invasive intraductal papillary mucinous carcinoma (IPMC) and invasive ductal carcinoma (IDC) of the pancreas to identify the reasons for these diseases' differing prognoses.Methods: We analyzed 114 and 560 patients who underwent curative pancreatectomy for invasive IPMC and IDC, respectively, and analyzed their clinicopathological factors.Results: The disease-specific survival (DSS) of patients with invasive IPMC was significantly superior to that of patients with IDC exhibiting all pathological types at all stages. The DSS of patients with invasive IPMC exhibiting tubular adenocarcinoma was significantly superior to that of their counterparts with IDC only among those with stage IIB (p = .045). When comparing patients with stage IIB tubular adenocarcinoma-type invasive IPMC to their counterparts with IDC, the tumor size (2.6 cm vs. 3.3 cm, p = .010), serum level of carbohydrate antigen 19-9 (253 vs. 474 U/mL, p = .035), number of metastatic lymph nodes (3.1 vs. 4.5, p = .033), vascular invasion rate (14% vs. 41%, p = .0019) and local invasion rate (79% vs. 95%, p = .0045) were lower in the former group. Moreover, the frequency of pathological tubular adenocarcinoma grade 1 was higher in patients with invasive IPMC than in those with IDC (38% vs. 12%, p = .0004) as was the R0 resection rate (90% vs. 65%, p = .0027).Conclusions: In pathological type- and stage-matched analyses, invasive IPMC was associated with a better prognosis than IDC only in patients with stage IIB, as factors governing tumor aggressiveness were milder in the former group than in the latter.

Adjuvant therapy in invasive intraductal papillary mucinous neoplasm (IPMN) of the pancreas: a systematic review

Intraductal papillary mucinous neoplasm (IPMN) of the pancreas is a cystic tumor with a disease spectrum ranging from low-grade dysplasia to invasive carcinoma. The evidence for adjuvant treatment in invasive IPMN is limited and mostly derived from studies in conventional pancreatic ductal adenocarcinoma (PDAC). We performed a systematic review focusing on all clinical studies concerning the efficacy of adjuvant therapy in patients with invasive IPMN. We identified 8 retrospective cohort studies, using either adjuvant chemotherapy alone (n=1), adjuvant radiotherapy alone (n=1) or adjuvant chemotherapy in combination with radiation (n=6). Adjuvant therapy was associated with a survival benefit in 7 out of the 8 studies. Specific survival benefit was noted for patients with node-positive disease, higher TNM stage, positive resection margins, poor differentiation and tubular subtype. We conclude that adjuvant therapy may be beneficial in invasive IPMN, but current data suggest that it should be given selectively based on individual tumor characteristics. Further prospective, randomized studies are warranted.

The management of intraductal papillary mucinous neoplasms of the pancreas

Intraductal papillary mucinous neoplasms (IPMN) of the pancreas are one of the most common preneoplastic entities among pancreatic cystic neoplasms (PCN). Their incidence is increasing due to an extensive use of cross-sectional imaging, but management still remains controversial. Among IPMNs, the main duct (MD-IPMN) and mixed (MT-IPMN) types harbor a high risk of malignant degeneration requiring resection in most of cases. The branch duct type (BD-IPMN), on the other side, can be safely surveilled as surgical resection is limited to selected cases deemed at high risk of malignant progression according to specific clinical and radiological features. An accurate diagnosis and a correct assessment of malignant potential are often hard to achieve, and clinical management still relies on the experience of the gastroenterologist/surgeon that is called to choose between a major pancreatic resection burdened by high morbidity and mortality rates and a life-long surveillance. The purpose of this report is to summarize the available evidence supporting the current practice for the management of IPMN and to offer a useful practical guide from first observation to postoperative follow-up.

AJCC 7th edition staging classification is more applicable than AJCC 8th edition staging classification for invasive IPMN

BACKGROUND

Both the 7th and 8th editions of the American Joint Committee on Cancer (AJCC) staging systems have been introduced for pancreatic adenocarcinoma. However, the applicability of these classifications for invasive intraductal papillary mucinous neoplasms (IPMN) has not been systematically examined.

METHODS

Patients with invasive IPMN were retrieved from a cohort of 18 geographical sites (1973-2014 varying) in the Surveillance, Epidemiology, and End Results (SEER) cancer registry. The 7th and 8th editions of the AJCC staging were compared. Survival rates and multivariate analyses were computed.

RESULTS

In total, 1216 patients with resected invasive IPMN were included. A major difference between the 7th and 8th systems is the definition of stage IIA (7th, beyond the pancreas without involvement of major arteries; 8th, maximum tumor diameter > 4 cm). The hazard ratio (HR) of stage IIA disease (versus stage IA, HR = 2.33, P < 0.001) was higher than that of stage IB disease (HR = 1.48, P = 0.087) by the 7th edition classification, whereas the HR of stage IIA disease (HR = 1.26, P = 0.232) was even lower than that of stage IB disease (HR = 1.48, P = 0.040) by the 8th edition classification. In addition, for the 8th edition staging system, tumor size was not a predictor of survival in patients with resectable tumor > 2 cm (size > 4 cm versus > 2 ≤ 4 cm, HR = 0.91, P = 0.420).

CONCLUSIONS

The AJCC 7th edition staging classification is more applicable than the 8th edition classification for invasive IPMN.

Pancreatic cancer thromboembolic outcomes: rate of thrombosis after adenocarcinoma and non-adenocarcinoma pancreatic cancer surgery

BACKGROUND

The aim of this study was to define the association of non-adenocarcinoma pancreatic cancer (NACPC) as a risk factor for postoperative cancer-associated thrombosis (CAT).

METHODS

We conducted analysis of prospectively collected data of pancreatic cancer surgery. Randomly collected NACPC cases were matched 1:3 to adenocarcinoma cases (ACPC). Variables included comorbidities, demographics, cancer extension, and preoperative Khorana score (KRS). Primary outcome was CAT, which included deep vein thrombosis and pulmonary embolism confirmed by imaging. Categorical variables are presented as percentages, continuous variables as median and range. SPSS, χ2, Cochran-Armitage, and logistic regression were use for analysis.

RESULTS

The study included 441 patients. Age 65.9±11.5, male 57% (N.=252), 8% (N.=36) had metastasis. IPMN and neuroendocrine were the most common NACPC. Median follow-up was 449 days in which 90 (20%) patients developed CAT. The odds (Odds Ratio [OR] 1.1, 95% Confidence Interval [CI] 0.6- 1.9, P=0.7) and time to venous thromboembolism were not different between NACPC and ACPC. We analyzed for trends of prophylactic strategies by year of surgery; there was no trend for NACPC (P=0.4) or ACPC (P=0.06). KRS was not associated with CAT. In the multivariate analysis, peripheral artery disease (Adjusted Odds Ratio [ORadj] 5.4, 95% CI: 1.7-17.3), ASA class ≥4 (ORadj 3.6; 95% CI: 1.3-10.4), length of stay >9 days (ORadj: 1.9; 1.2-3.2), and cancer vascular invasion (ORadj: 2.9; 95% CI: 1.6-5.3) were associated with CAT.

CONCLUSIONS

The rate of VTE in NACPC after surgery was high and not different than ACPC. Histology type should not govern discrimination in thromboprophylaxis selection or extension.

Adjuvant chemotherapy is associated with improved postoperative survival in specific subtypes of invasive intraductal papillary mucinous neoplasms (IPMN) of the pancreas: it is time for randomized controlled data

BACKGROUND

Very little is known about adjuvant chemotherapy for invasive Intraductal Papillary Mucinous Neoplasms (IPMNs) of the pancreas. The aim was to assess whether adjuvant chemotherapy affects survival.

METHODS

Retrospective evaluation of invasive IPMNs. Patients treated with surgery alone or followed by adjuvant chemotherapy were compared in terms of survival.

RESULTS

A total of 102 invasive IPMNs were analyzed. Median follow-up was 72 (5-318) months and 18.6% received adjuvant chemotherapy. Overall, recurrence rate was 40.2%, while 5-year overall survival and disease specific survival (DSS) were 65.3% and 69.4%, respectively. N1 disease (HR5.58, CI95% 2.49-12.51, p < 0.01), tubular type (HR2.35, CI95% 1.71-4.82, p = 0.05) and G3 tumors (HR4.54, CI95% 2.12-15.49, <0.01) were predictors of reduced DSS. Overall, there was no difference in the 5-year DSS comparing patients treated with adjuvant chemotherapy to surgery alone (61.8 vs. 69.4%, p = 0.8). Adjuvant chemotherapy significantly improved DSS only in N1 (5-years-DSS 76 vs. 35.8%, p = 0.01) and tubular carcinomas (5-years-DSS 88.9 vs. 53%, p = 0.03).

CONCLUSIONS

Adjuvant therapy improves survival only in invasive IPMNs with nodal disease or tubular differentiation. Future trials are needed to improve the level of evidence about adjuvant chemotherapy.

Screening responsive or resistant biomarkers of immune checkpoint inhibitors based on online databases

Immune checkpoint inhibitors are a promising strategy in the treatment of cancer, especially advanced types. However, not all patients are responsive to immune checkpoint inhibitors. The response rate depends on the immune microenvironment, tumor mutational burden (TMB), expression level of immune checkpoint proteins, and molecular subtypes of cancers. Along with the Cancer Genome Project, various open access databases, including The Cancer Genome Atlas and Gene Expression Omnibus, provide large volumes of data, which allow researchers to explore responsive or resistant biomarkers of immune checkpoint inhibitors. In this review, we introduced some methodologies on database selection, biomarker screening, current progress of immune checkpoint blockade in solid tumor treatment, possible mechanisms of drug resistance, strategies of overcoming resistance, and indications for immune checkpoint inhibitor therapy.

Comparison of the Survival Outcomes of Pancreatic Cancer and Intraductal Papillary Mucinous Neoplasms

OBJECTIVES

The aims of the study were to compare survival outcomes between patients with pancreatic ductal adenocarcinoma (PDAC) and invasive intraductal papillary mucinous neoplasms (IPMN) and to determine candidates for adjuvant chemotherapy.

METHODS

A total of 579 consecutive patients, including 375 PDAC and 204 IPMN patients, were reviewed. Stage-matched comparisons of survival data were conducted using the Cox proportional hazards model and propensity analysis. To evaluate prognostic factors, univariate and multivariate Cox regression analyses were performed.

RESULTS

The overall survival for invasive IPMN was significantly longer than that for PDAC (hazard ratio, 2.34; P = 0.0001). When the analysis was limited to stage I patients, the 5-year overall survival rate of invasive IPMN patients was significantly better than that of PDAC patients (100% vs 74.1%, P = 0.0092); however, no difference was observed between stage II patients with invasive IPMN and PDAC (hazard ratio, 1.49; P = 0.09). The Cox proportional hazards model and propensity analysis demonstrated no difference in stage-matched survival. Multivariate analysis revealed that only T (≥3) was an independent prognostic factor for invasive IPMN.

CONCLUSIONS

Stage-matched analysis did not show a significant survival difference between invasive IPMN and PDAC patients, and T3 or higher was an independent prognostic factor for invasive IPMN.