Predictors, Patterns, and Timing of Recurrence Provide Insight into the Disease Biology of Invasive Carcinomas Arising in Association with Intraductal Papillary Mucinous Neoplasms

Impact of Adjuvant Chemotherapy on Resected Intraductal Papillary Mucinous Neoplasm-Derived Pancreatic Cancer: Results From an International Multicenter Study

PURPOSE

The benefit of adjuvant therapy for intraductal papillary mucinous neoplasm (IPMN)-derived pancreatic ductal adenocarcinoma (PDAC) remains unclear because of severely limited evidence. Although biologically distinct entities, adjuvant therapy practices for IPMN-derived PDAC are largely founded on pancreatic intraepithelial neoplasia-derived PDAC. We aimed to evaluate the role of adjuvant chemotherapy in IPMN-derived PDAC.

METHODS

This international multicenter retrospective cohort study (2005-2018) was conceived at the Verona Evidence-Based Medicine meeting. Cox regressions were performed to identify risk-adjusted hazard ratios (HR) associated with overall survival (OS). Kaplan-Meier curves and log-rank tests were employed for survival analysis. Logistic regression was performed to identify factors motivating adjuvant chemotherapy administration. A decision tree was proposed and categorized patients into overtreated, undertreated, and optimally treated cohorts.

RESULTS

In 1,031 patients from 16 centers, nodal disease (HR, 2.88, P < .001) and elevated (≥37 to <200 µ/mL, HR, 1.44, P = .006) or markedly elevated (≥200 µ/mL, HR, 2.53, P < .001) carbohydrate antigen 19-9 (CA19-9) were associated with worse OS. Node-positive patients with elevated CA19-9 had an associated 34.4-month improvement in median OS (P = .047) after adjuvant chemotherapy while those with positive nodes and markedly elevated CA19-9 had an associated 12.6-month survival benefit (P < .001). Node-negative patients, regardless of CA19-9, did not have an associated benefit from adjuvant chemotherapy (all P > .05). Based on this model, we observed undertreatment in 18.1% and overtreatment in 61.2% of patients. Factors associated with chemotherapy administration included younger age, R1-margin, poorer differentiation, and nodal disease.

CONCLUSION

Almost half of patients with resected IPMN-derived PDAC may be overtreated or undertreated. In patients with node-negative disease or normal CA19-9, adjuvant chemotherapy is not associated with a survival benefit, whereas those with node-positive disease and elevated CA19-9 have an associated benefit from adjuvant chemotherapy. A decision tree was proposed. Randomized controlled trials are needed for validation.

Defining and Predicting Early Recurrence for Optimal Treatment Strategies for Intraductal Papillary Mucinous Neoplasm-Derived Pancreatic Cancer: An International Multicenter Study

BACKGROUND

Early recurrence in intraductal papillary mucinous neoplasm (IPMN)-derived pancreatic ductal adenocarcinoma (PDAC) is poorly defined. Predictors are lacking and needed for patient counseling, risk stratification, and postoperative management. This study aimed to define and predict early recurrence for patients in resected IPMN-derived PDAC and guide management.

METHODS

A lowest p value for survival after recurrence (SAR) was used to define early recurrence in resected IPMN-derived PDAC from five international centers. Overall survival (OS) and SAR were compared using log-rank tests. A multivariable logistic regression identified odds ratios (ORs) with 95 % confidence intervals (CIs) for early recurrence. Rounded ORs were used to stratify patients into low-, intermediate-, and high-risk groups using upper and lower quartile score distributions. Adjuvant chemotherapy was assessed by Cox regression and log-rank tests for OS in risk groups.

RESULTS

Recurrence developed in 160 (42 %) of 381 patients. Early recurrence was defined at 10.5 months and observed in 61 patients (38 % of recurrences). The median SAR for the patients with early recurrence was 8.3 months (95 % CI, 3.1-16.1 months) compared with 12.9 months (95 % CI, 5.2-27.5 months) for the patients with late recurrence. The independent predictors of early recurrence were CA19-9 (OR, 3.80; 95 % CI, 1.54-9.41) and N2 disease (OR, 7.29; 95 % CI, 3.22-16.49). The early recurrence rates in the low-, intermediate-, and high-risk groups were respectively 1 %, 14 %, and 32 %. Adjuvant chemotherapy was associated with improved OS only for the high-risk patients (hazard ratio, 0.50; 95 % CI, 0.32-0.79).

CONCLUSION

In IPMN-derived PDAC, the optimal cutoff for early recurrence is 10.5 months. Both CA19-9 and N stage predict early recurrence. Adjuvant chemotherapy is associated with survival benefit only for high-risk patients.

Evaluation of AJCC Nodal Staging for Intraductal Papillary Mucinous Neoplasm-Derived Pancreatic Ductal Adenocarcinoma

BACKGROUND

The American Joint Committee on Cancer (AJCC) eighth edition is based on pancreatic intraepithelial neoplasia-derived pancreatic ductal adenocarcinoma (PDAC), a biologically distinct entity from intraductal papillary mucinous neoplasm (IPMN)-derived pancreatic cancer. The role of nodal disease and the AJCC's prognostic utility for IPMN-derived pancreatic cancer are unclear. This study aimed to evaluate the prognostic role of nodal disease and the AJCC eighth-edition N-staging for IPMN-derived pancreatic cancer.

METHODS

Upfront-surgery patients with IPMN-derived PDAC from four centers were stratified according to the AJCC eighth-edition N stage. Disease characteristics were compared using descriptive statistics, and both overall survival (OS) and recurrence-free survival (RFS) were evaluated using log-rank tests. Multivariable Cox regression was performed to determine the prognostic value of N stage for OS, presented as hazard ratios with 95 % confidence intervals (95 % CIs). A lowest p value log-rank statistic was used to derive the optimal cutoff for node-positive disease.

RESULTS

For 360 patients, advanced N stage was associated with worse T stage, grade, tubular histology, and perineural and lymphovascular invasion (all p < 0.05). The median OS was 98.3 months (95 % CI 82.8-122.0 months) for N0 disease, 27.8 months (95 % CI 24.4-41.7 months) for N1 disease, and 18.1 months (95 % CI 16.2-25.9 months) for N2 disease (p < 0.001). The AJCC N stage was validated and associated with worse OS (N1 [HR 1.64; range, 1.05-2.57], N2 [HR2.42; range, 1.48-3.96]) and RFS (N1 [HR 1.81; range, 1.23-2.68], N2 [HR 3.72; range, 2.40-5.77]). The optimal cutoff for positive nodes was five nodes.

CONCLUSION

The AJCC eighth-edition N-staging is valid and prognostic for both OS and RFS in IPMN-derived PDAC.

Outcomes in intraductal papillary mucinous neoplasm-derived pancreatic cancer differ from PanIN-derived pancreatic cancer

BACKGROUND AND AIM

Intraductal papillary mucinous neoplasm (IPMN)-derived pancreatic ductal adenocarcinoma (PDAC) management is generally extrapolated from pancreatic intraepithelial neoplasia (PanIN)-derived PDAC guidelines. However, these are biologically divergent, and heterogeneity further exists between tubular and colloid subtypes.

METHODS

Consecutive upfront surgery patients with PanIN-derived and IPMN-derived PDAC were retrospectively identified from international centers (2000-2019). One-to-one propensity score matching for clinicopathologic factors generated three cohorts: IPMN-derived versus PanIN-derived PDAC, tubular IPMN-derived versus PanIN-derived PDAC, and tubular versus colloid IPMN-derived PDAC. Overall survival (OS) was compared using Kaplan-Meier and log-rank tests. Multivariable Cox regression determined corresponding hazard ratios (HR) and 95% confidence intervals (95% CI).

RESULTS

The median OS (mOS) in 2350 PanIN-derived and 700 IPMN-derived PDAC patients was 23.0 and 43.1 months (P < 0.001), respectively. PanIN-derived PDAC had worse T-stage, CA19-9, grade, and nodal status. Tubular subtype had worse T-stage, CA19-9, grade, nodal status, and R1 margins, with a mOS of 33.7 versus 94.1 months (P < 0.001) in colloid. Matched (n = 495), PanIN-derived and IPMN-derived PDAC had mOSs of 30.6 and 42.8 months (P < 0.001), respectively. In matched (n = 341) PanIN-derived and tubular IPMN-derived PDAC, mOS remained poorer (27.7 vs 37.4, P < 0.001). Matched tubular and colloid cancers (n = 112) had similar OS (P = 0.55). On multivariable Cox regression, PanIN-derived PDAC was associated with worse OS than IPMN-derived (HR: 1.66, 95% CI: 1.44-1.90) and tubular IPMN-derived (HR: 1.53, 95% CI: 1.32-1.77) PDAC. Colloid and tubular subtype was not associated with OS (P = 0.16).

CONCLUSIONS

PanIN-derived PDAC has worse survival than IPMN-derived PDAC supporting distinct outcomes. Although more indolent, colloid IPMN-derived PDAC has similar survival to tubular after risk adjustment.

An international multi-institutional validation of T1 sub-staging of intraductal papillary mucinous neoplasm-derived pancreatic cancer

BACKGROUND

Intraductal papillary mucinous neoplasm (IPMN)-derived pancreatic ductal adenocarcinoma (PDAC) is resected at smaller sizes compared with its biologically distinct counterpart, pancreatic intraepithelial neoplasia (PanIN)-derived PDAC. Thus, experts proposed T1 sub-staging for IPMN-derived PDAC. However, this has never been validated.

METHODS

Consecutive upfront surgery patients with IPMN-derived PDAC from 5 international high-volume centers were classified by the proposed T1 sub-staging classification (T1a ≤0.5, T1b >0.5 and ≤1.0, and T1c >1.0 and ≤2.0 cm) using the invasive component size. Kaplan-Meier and log-rank tests were used to compare overall survival (OS). A multivariable Cox regression was used to determine hazard ratios (HRs) with confidence intervals (95% CIs).

RESULTS

Among 747 patients, 69 (9.2%), 50 (6.7%), 99 (13.0%), and 531 patients (71.1%), comprised the T1a, T1b, T1c, and T2-4 subgroups, respectively. Increasing T-stage was associated with elevated CA19-9, poorer grade, nodal positivity, R1 margin, and tubular subtype. Median OS for T1a, T1b, T1c, and T2-4 were 159.0 (95% CI = 126.0 to NR), 128.8 (98.3 to NR), 77.6 (48.3 to 108.2), and 31.4 (27.5 to 37.7) months, respectively (P < .001). OS decreased with increasing T-stage for all pairwise comparisons (all P < .05). After risk adjustment, older than age 65, elevated CA19-9, T1b [HR = 2.55 (1.22 to 5.32)], T1c [HR = 3.04 (1.60 to 5.76)], and T2-4 [HR = 3.41 (1.89 to 6.17)] compared with T1a, nodal positivity, R1 margin, and no adjuvant chemotherapy were associated with worse OS. Disease recurrence was more common in T2-4 tumors (56.4%) compared with T1a (18.2%), T1b (23.9%), and T1c (36.1%, P < .001).

CONCLUSION

T1 sub-staging of IPMN-derived PDAC is valid and has significant prognostic value. Advancing T1 sub-stage is associated with worse histopathology, survival, and recurrence. T1 sub-staging is recommended for future guidelines.

A Review of the Indications, Outcomes, and Postoperative Management After Total and Completion Pancreatectomy for Pancreatic Cancer: More Is Not Necessarily Better

With improvements in surgical technique and advances in pancreatic endocrine and exocrine replacement therapy, the indications for, and threshold to perform, total or completion pancreatectomy in the modern surgical era are ever evolving. The following review will evaluate such indications for pancreatic cancer including pancreatic ductal adenocarcinoma and intraductal papillary mucinous neoplasms. The authors also review the literature on oncologic outcomes of total and completion pancreatectomy for pancreatic cancer. Finally, they discuss the quality of life and postoperative management of the a-pancreatic state.

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.

Predictors of long-term survival after resection of adenocarcinoma arising from intraductal papillary mucinous neoplasm and derivation of a prognostic model: An international multicenter study (ADENO-IPMN study)

BACKGROUND

Predictors of long-term survival after resection of adenocarcinoma arising from intraductal papillary mucinous neoplasms are unknown. This study determines predictors of long-term (>5 years) disease-free survival and recurrence in adenocarcinoma arising from intraductal papillary mucinous neoplasms and derives a prognostic model for disease-free survival.

METHODS

Consecutive patients who underwent pancreatic resection for adenocarcinoma arising from intraductal papillary mucinous neoplasms in 18 academic pancreatic centers in Europe and Asia between 2010 to 2017 with at least 5-year follow-up were identified. Factors associated with disease-free survival were determined using Cox proportional hazards model. Internal validation was performed, and discrimination and calibration indices were assessed.

RESULTS

In the study, 288 patients (median age, 70 years; 52% male) were identified; 140 (48%) patients developed recurrence after a median follow-up of 98 months (interquartile range, 78.4-123), 57 patients (19.8%) developed locoregional recurrence, and 109 patients (37.8%) systemic recurrence. At 5 years after resection, the overall and disease-free survival was 46.5% (134/288) and 35.0% (101/288), respectively. On Cox proportional hazards model analysis, multivisceral resection (hazard ratio, 2.20; 95% confidence interval, 1.06-4.60), pancreatic tail location (hazard ratio, 2.34; 95% confidence interval, 1.22-4.50), poor tumor differentiation (hazard ratio, 2.48; 95% confidence interval, 1.10-5.30), lymphovascular invasion (hazard ratio, 1.74; 95% confidence interval, 1.06-2.88), and perineural invasion (hazard ratio, 1.83; 95% confidence interval, 1.09-3.10) were negatively associated with long-term disease-free survival. The final predictive model incorporated 8 predictors and demonstrated good predictive ability for disease-free survival (C-index, 0.74; calibration, slope 1.00).

CONCLUSION

A third of patients achieve long-term disease-free survival (>5 years) after pancreatic resection for adenocarcinoma arising from intraductal papillary mucinous neoplasms. The predictive model developed in the current study can be used to estimate the probability of long-term disease-free 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.

Long-Term Oncologic Outcome following Duodenum-Preserving Pancreatic Head Resection for Benign Tumors, Cystic Neoplasms, and Neuroendocrine Tumors: Systematic Review and Meta-analysis

BACKGROUND

Pancreatoduodenectomy (PD) has a considerable surgical risk for complications and late metabolic morbidity. Parenchyma-sparing resection of benign tumors has the potential to cure patients associated with reduced procedure-related short- and long-term complications.

MATERIALS AND METHODS

Pubmed, Embase, and Cochrane libraries were searched for studies reporting surgery-related complications following PD and duodenum-preserving total (DPPHRt) or partial (DPPHRp) pancreatic head resection for benign tumors. A total of 38 cohort studies that included data from 1262 patients were analyzed. In total, 729 patients underwent DPPHR and 533 PD.

RESULTS

Concordance between preoperative diagnosis of benign tumors and final histopathology was 90.57% for DPPHR. Cystic and neuroendocrine neoplasms (PNETs) and periampullary tumors (PATs) were observed in 497, 89, and 31 patients, respectively. In total, 34 of 161 (21.1%) patients with intraepithelial papillar mucinous neoplasm exhibited severe dysplasia in the final histopathology. The meta-analysis, when comparing DPPHRt and PD, revealed in-hospital mortality of 1/362 (0.26%) and 8/547 (1.46%) patients, respectively [OR 0.48 (95% CI 0.15-1.58); p = 0.21], and frequency of reoperation of 3.26 % and 6.75%, respectively [OR 0.52 (95% CI 0.28-0.96); p = 0.04]. After a follow-up of 45.8 ± 26.6 months, 14/340 patients with intraductal papillary mucinous neoplasms/mucinous cystic neoplasms (IPMN/MCN, 4.11%) and 2/89 patients with PNET (2.24%) exhibited tumor recurrence. Local recurrence at the resection margin and reoccurrence of tumor growth in the remnant pancreas was comparable after DPPHR or PD [OR 0.94 (95% CI 0.178-5.34); p = 0.96].

CONCLUSIONS

DPPHR for benign, premalignant neoplasms provides a cure for patients with low risk of tumor recurrence and significantly fewer early surgery-related complications compared with PD. DPPHR has the potential to replace PD for benign, premalignant cystic and neuroendocrine neoplasms.

Novel Insights into Postoperative Surveillance in Resected Pancreatic Cystic Neoplasms-A Review

Pancreatic cystic lesions (PCL) are frequently encountered in clinical practice and some are referred to surgery due to their neoplastic risk or malignant transformation. The management of PCL involves complex decision-making, with postoperative surveillance being a key component for long-term outcomes, due to the potential for recurrence and postoperative morbidity. Unfortunately, the follow-up of resected patients is far from being optimal and there is a lack of consensus on recommendations with regard to timing and methods of surveillance. Here, we summarize the current knowledge on the postoperative surveillance of neoplastic pancreatic cysts, focusing on the mechanisms and risk factors for recurrence, the recurrence rates according to the initial indication for surgery, the final result of the surgical specimen and neoplastic risk in the remaining pancreas, as well as the postsurgical morbidity comprising pancreatic exocrine insufficiency, metabolic dysfunction and diabetes after resection, according to the type of surgery performed. We analyze postsurgical recurrence rates and morbidity profiles, as influenced by different surgical techniques, to better delineate at-risk patients, and highlight the need for tailored surveillance strategies adapted to preoperative and operative factors with an impact on outcomes.

Optimal age to discontinue long-term surveillance of intraductal papillary mucinous neoplasms: comparative cost-effectiveness of surveillance by age

OBJECTIVE

Current guidelines recommend long-term image-based surveillance for patients with low-risk intraductal papillary mucinous neoplasms (IPMNs). This simulation study aimed to examine the comparative cost-effectiveness of continued versus discontinued surveillance at different ages and define the optimal age to stop surveillance.

DESIGN

We constructed a Markov model with a lifetime horizon to simulate the clinical course of patients with IPMNs receiving imaging-based surveillance. We calculated incremental cost-effectiveness ratios (ICERs) for continued versus discontinued surveillance at different ages to stop surveillance, stratified by sex and IPMN types (branch-duct vs mixed-type). We determined the optimal age to stop surveillance as the lowest age at which the ICER exceeded the willingness-to-pay threshold of US$100 000 per quality-adjusted life year. To estimate model parameters, we used a clinical cohort of 3000 patients with IPMNs and a national database including 40 166 patients with pancreatic cancer receiving pancreatectomy as well as published data.

RESULTS

In male patients, the optimal age to stop surveillance was 76-78 years irrespective of the IPMN types, compared with 70, 73, 81, and 84 years for female patients with branch-duct IPMNs <20 mm, =20-29 mm, ≥30 mm and mixed-type IPMNs, respectively. The suggested ages became younger according to an increasing level of comorbidities. In cases with high comorbidity burden, the ICERs were above the willingness-to-pay threshold irrespective of sex and the size of branch-duct IPMNs.

CONCLUSIONS

The cost-effectiveness of long-term IPMN surveillance depended on sex, IPMN types, and comorbidity levels, suggesting the potential to personalise patient management from the health economic perspective.

Current considerations on intraductal papillary neoplasms of the bile duct and pancreatic duct

Pancreatobiliary intraductal papillary neoplasms (IPNs) represent precursors of pancreatic cancer or bile duct cholangiocarcinoma that can be detected and treated. Despite advances in diagnostic methods, identifying these premalignant lesions is still challenging for treatment providers. Modern imaging, biomarkers and molecular tests for genomic alterations can be used for diagnosis and follow-up. Surgical intervention in combination with new chemotherapeutic agents is considered the optimal treatment for malignant cases. The balance between the risk of malignancy and any risk of resection guides management policy; therefore, treatment should be individualized based on a meticulous preoperative assessment of high-risk stigmata. IPN of the bile duct is more aggressive; thus, early diagnosis and surgery are crucial. The conservative management of low-risk pancreatic branch-duct lesions is safe and effective.

The Role of Intraoperative Pancreatoscopy in the Surgical Management of Intraductal Papillary Mucinous Neoplasms: A Scoping Review

OBJECTIVES

Most patients with intraductal papillary mucinous neoplasms (IPMNs) are diagnosed with a solitary lesion; however, the presence of skip lesions, not appreciable on imaging, has been described. Postoperatively, these missed lesions can continue to grow and potentially become cancerous. Intraoperative pancreatoscopy (IOP) may facilitate detection of such skip lesions in the remnant gland. The aim of this scoping review was to appraise the evidence on the role of IOP in the surgical management of IPMNs.

MATERIALS AND METHODS

Studies reporting on the use of IOP during IPMN surgery were identified through searches of the PubMed, Embase, and Scopus databases. Data extracted included IOP findings, surgical plan modifications, and patient outcomes. The primary outcome of interest was the utility of IOP in surgical decision making.

RESULTS

Ten studies reporting on the use of IOP for IPMNs were identified, representing 147 patients. A total of 46 skip lesions were identified by IOP. Overall, surgical plans were altered in 37% of patients who underwent IOP. No IOP-related complications were reported.

CONCLUSIONS

The current literature suggests a potential role of integration of IOP into the management of patients with IPMNs. This tool is safe and feasible and can result in changes in surgical decision making.