Defining the Minimal and Optimal Thresholds for Lymph Node Resection and Examination for Intraductal Papillary Mucinous Neoplasm Derived Pancreatic Cancer: A Multicenter Retrospective Analysis.

OBJECTIVE: To establish minimal and optimal lymphadenectomy thresholds for intraductal papillary mucinous neoplasm (IPMN)-derived pancreatic ductal adenocarcinoma (PDAC) and evaluate their prognostic value. BACKGROUND: Current guidelines recommend a minimum of 12-15 lymph nodes (LNs) in PDAC. This is largely based on pancreatic intraepithelial neoplasia (PanIN)-derived PDAC, a biologically distinct entity from IPMN-derived PDAC. METHODS: Multicenter retrospective study including consecutive patients undergoing upfront surgery for IPMN-derived PDAC was conducted. The minimum cut-off for lymphadenectomy was defined as the maximum number of LNs where a significant node positivity difference was observed. Maximally selected log-rank statistic was used to derive the optimal lymphadenectomy cut-off (maximize survival). Kaplan-Meier curves and log-rank tests were used to analyze overall survival (OS) and recurrence-free survival (RFS). Multivariable Cox-regression was used to determine hazard ratios (HR) with 95% confidence intervals (95%CI). RESULTS: In 341 patients with resected IPMN-derived PDAC, the minimum number of LNs needed to ensure accurate nodal staging was 10 (P=0.040), whereas ≥20 LNs was the optimal number associated with improved OS (80.3 vs. 37.2 mo, P<0.001). Optimal lymphadenectomy was associated with improved OS [HR:0.57 (95%CI 0.39-0.83)] and RFS [HR:0.70 (95%CI 0.51-0.97)] on multivariable Cox-regression. On sub-analysis the optimal lymphadenectomy cut-offs for pancreatoduodenectomy, distal pancreatectomy, and total pancreatectomy were 20 (P<0.001), 23 (P=0.160), and 25 (P=0.008). CONCLUSION: In IPMN-derived PDAC, lymphadenectomy with at least 10 lymph nodes mitigates under-staging, and at least 20 lymph nodes is associated with the improved survival. Specifically, for pancreatoduodenectomy and total pancreatectomy, 20 and 25 lymph nodes were the optimal cut-offs.

Informing Decision-making for Transected Margin Reresection in Intraductal Papillary Mucinous Neoplasm-derived PDAC: An International Multicenter Study.

OBJECTIVE: To assess the prognostic impact of margin status in patients with resected intraductal papillary mucinous neoplasms (IPMN)-derived pancreatic ductal adenocarcinoma (PDAC) and to inform future intraoperative decision-making on handling differing degrees of dysplasia on frozen section. SUMMARY BACKGROUND DATA: The ideal oncologic surgical outcome is a negative transection margin with normal pancreatic epithelium left behind. However, the prognostic significance of reresecting certain degrees of dysplasia or invasive cancer at the pancreatic neck margin during pancreatectomy for IPMN-derived PDAC is debatable. METHODS: Consecutive patients with resected and histologically confirmed IPMN-derived PDAC (2002-2022) from six international high-volume centers were included. The prognostic relevance of a positive resection margin (R1) and degrees of dysplasia at the pancreatic neck margin were assessed by log-rank test and multivariable Cox-regression for overall survival (OS) and recurrence-free survival (RFS). RESULTS: Overall, 832 patients with IPMN-derived PDAC were included with 322 patients (39%) having an R1-resection on final pathology. Median OS (mOS) was significantly longer in patients with an R0 status compared to those with an R1 status (65.8 vs. 26.3 mo P<0.001). Patients without dysplasia at the pancreatic neck margin had similar OS compared to those with low-grade dysplasia (mOS: 78.8 vs. 66.8 months, P=0.344). However, high-grade dysplasia (mOS: 26.1 mo, P=0.001) and invasive cancer (mOS: 25.0 mo, P<0.001) were associated with significantly worse OS compared to no or low-grade dysplasia. Patients who underwent conversion of high-risk margins (high-grade or invasive cancer) to a low-risk margin (low-grade or no dysplasia) after intraoperative frozen section had significantly superior OS compared to those with a high-risk neck margin on final pathology (mOS: 76.9 vs. 26.1 mo P<0.001). CONCLUSIONS: In IPMN-derived PDAC, normal epithelium or low-grade dysplasia at the neck have similar outcomes while pancreatic neck margins with high-grade dysplasia or invasive cancer are associated with poorer outcomes. Conversion of a high-risk to low-risk margin after intraoperative frozen section is associated with survival benefit and should be performed when feasible.

Total versus Partial Pancreatectomy in Patients with Pancreatic Cancer Arising from Multifocal or Diffuse Intraductal Papillary Mucinous Neoplasia - A Multicenter Observational Study.

AIM: To investigate the impact of total pancreatectomy (TP) on oncological outcomes for patients at high-risk of local recurrence or secondary progression in the remnant gland after partial pancreatectomy (PP) for IPMN-associated cancer. SUMMARY BACKGROUND DATA: Major risk factors for invasive progression in the remnant gland include multifocality, diffuse main duct dilation, and the presence of invasive cancer. In these high-risk patients, a TP may be oncologically beneficial. However, current guidelines discourage TP, especially in elderly patients. METHODS: This international multicenter study compares TP versus PP in patients with adenocarcinoma arising from multifocal or diffuse IPMN (2002-2022). Log-rank test and multivariable Cox-analysis with interaction analysis was performed to assess overall survival (OS), disease-free survival (DFS), and local-DFS. RESULTS: Of 359 included patients, 162 (45%) were treated with TP, whereas 197 (55%) underwent PP. Despite TP and PP having similar R0-rates (59% vs. 58%, P=0.866), patients undergoing a TP had significantly longer local-DFS compared to PP (P=0.039). However, no difference in OS was observed between the two surgical approaches (P=0.487). In a multivariable analysis, young age (optimal cut-off ≤63.6 yrs) was associated with an OS benefit derived from TP (HR:0.44, 95%CI:0.22-0.89), whereas no significant difference was observed in elderly patients (HR:1.24, 95%CI:0.92-1.67, Pinteraction=0.007). CONCLUSION: Since overall, patients with diffuse or multifocal IPMN with an invasive component do not benefit from TP in terms of OS, the indication for TP may be individualized to young patients who have sufficient life expectancy to benefit from the prevention of secondary progression or local recurrence.

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 to 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 five 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 utilized to compare overall survival (OS). A multivariable Cox-regression was used to determine hazard ratios (HR) with confidence intervals (95%CI). 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-NR), 128.8 (98.3-NR), 77.6 (48.3-108.2), and 31.4 (27.5-37.7) months, respectively (p < .001). OS decreased with increasing T-stage for all pairwise comparisons (all p < .05). After risk-adjustment, age > 65, elevated CA19-9, T1b [HR : 2.55 (1.22-5.32)], T1c [HR : 3.04 (1.60-5.76)], and T2-4 [HR : 3.41 (1.89-6.17)] compared to 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 to 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 nationwide assessment of hepatocellular adenoma resection: Indications and pathological discordance.

Hepatocellular adenomas (HCAs) are benign liver tumors associated with bleeding or malignant transformation. Data on the indication for surgery are scarce. We analyzed indications and outcome of patients operated for HCAs < 50 mm compared to HCAs ≥ 50 mm. Changes in final postoperative diagnosis were assessed. We performed a retrospective study that included patients who underwent resection for (suspected) HCAs in the Netherlands from 2014 to 2019. Indication for resection was analyzed and stratified for small (<50 mm) and large (≥50 mm) tumors. Logistic regression analysis was performed on factors influencing change in tumor diagnosis. Out of 222 patients who underwent surgery, 44 (20%) patients had a tumor <50 mm. Median age was 46 (interquartile range [IQR], 33-56) years in patients with small tumors and 37 (IQR, 31-46) years in patients with large tumors ( p  = 0.016). Patients with small tumors were more frequently men (21% vs. 5%, p  = 0.002). Main indications for resection in patients with small tumors were suspicion of (pre)malignancy (55%), (previous) bleeding (14%), and male sex (11%). Patients with large tumors received operations because of tumor size >50 mm (52%), suspicion of (pre)malignancy (28%), and (previous) bleeding (5.1%). No difference was observed in HCA-subtype distribution between small and large tumors. Ninety-six (43%) patients had a postoperative change in diagnosis. Independent risk factors for change in diagnosis were tumor size <50 mm (adjusted odds ratio [aOR], 3.4; p  < 0.01), male sex (aOR, 3.7; p  = 0.03), and lack of hepatobiliary contrast-enhanced magnetic resonance imaging (CE-MRI) (aOR, 1.8; p  = 0.04). Resection for small (suspected) HCAs was mainly indicated by suspicion of (pre)malignancy, whereas for large (suspected) HCAs, tumor size was the most prevalent indication. Male sex, tumor size <50 mm, and lack of hepatobiliary CE-MRI were independent risk factors for postoperative change in tumor diagnosis.

Safety and feasibility of rigid fixation by SternaLock Blu plates during the modified Ravitch procedure: a pilot study.

BACKGROUND: Patients with anterior chest wall deformities unsuitable for minimally invasive repair are commonly treated by the modified Ravitch procedure. Although rigid plate fixation of the sternal osteotomy has previously shown to facilitate adequate sternal union, its use is troubled by an implant removal rate of up to 23% due to local complaints or complications associated with bulky plates. In contrast, the use of thinner and therefore biomechanically weaker plates may result in a higher incidence of non- or mal-union. In this pilot study, we evaluate the feasibility, efficacy and safety of rigid sternal fixation by thin pre-shaped anatomical locking plates during the modified Ravitch procedure. METHODS: Between June 2018 and December 2019, all consecutive patients who underwent anterior chest wall deformity repair by the modified Ravitch procedure in our tertiary referral centre were included. Data was collected retrospectively. All pectus types were included. The sternal osteotomy was fixated using thin SternaLock Blu plates. Patients were followed for at least one year. RESULTS: Nine patients were included. The group consisted of six male and three female patients, with a median age of 20 years [interquartile range (IQR), 16-35 years]. Median duration of follow-up was 25 months (IQR, 16-28 months). No intraoperative complications occurred. No patients presented with symptomatic non- or mal-union. Plate removal was performed in one patient for atypical pain without relief. No other postoperative complications occurred. CONCLUSIONS: Based on these pilot results, thin SternaLock Blu plates are deemed to be safe and effective in providing adequate rigid fixation of the sternal osteotomy during the modified Ravitch procedure. Compared to literature, the need for plate removal within 25 months after surgery was reduced.

A case series: xiphoidectomy for xiphodynia, a rare thoracic wall disorder.

BACKGROUND: Xiphodynia is a rare musculoskeletal disorder characterized by pain at the lower anterior chest or epigastric region. Treatment options include oral analgesics, local injection with analgesic or laser therapy. Yet, these often provide only short-term symptom relieve. A definite reduction in pain sensation might be achieved by performing a xiphoidectomy, though studies on its safety and efficacy are scarce. In the current single-centre study the outcomes of xiphoidectomy for xiphodynia are retrospectively assessed. METHODS: All patients undergoing xiphoidectomy for xiphodynia between April 2013 and February 2020 at Zuyderland Medical Centre, Heerlen, the Netherlands, were included in this case series. Pain scores using the Numeric Rating Scale were assessed preoperatively and postoperatively and submitted to the Wilcoxon signed rank test. A clinically significant improvement was defined as a 2-point decrease in Numeric Rating Scale score. In addition, surgical outcomes, including complications and duration of surgery were extracted from the patient records. RESULTS: A total of 19 patients underwent xiphoidectomy for xiphodynia. The follow-up ranged from 1 to 83 months. Seventeen out of 19 patients showed a clinically relevant improvement in Numeric Rating Scale pain scores where the overall pain scores also revealed a statistically significant decrease from 8 (interquartile range, 7-8) to 0 (interquartile range, 0-0; P<0.001) after surgery. Median procedure time was 29 minutes (interquartile range, 24-38 minutes) and no postoperative complications occurred. CONCLUSIONS: Xiphoidectomy for xiphodynia is a safe and effective surgical procedure with good outcomes on pain relief. Though, future comparative studies are urged to elucidate its value among other treatment options.