Peritoneal metastases from gastric cancer in a nationwide cohort: Incidence, treatment and survival.

The aims of this study were to investigate incidence, risk factors and treatment of synchronous or metachronous peritoneal metastases (PM) from gastric cancer and to estimate survival of these patients using population-based data. Patients diagnosed with gastric cancer in 2015 to 2016 were selected from the Netherlands Cancer Registry. The incidence of synchronous and metachronous PM were calculated. Multivariable regression analyses were performed to identify factors associated with the occurrence of PM. Treatment and survival were compared between patients with synchronous and metachronous PM. Of 2206 patients with gastric cancer, 741 (34%) were diagnosed with PM. Of these, 498 (23%) had synchronous PM. The cumulative incidence of metachronous PM in patients who underwent potentially curative treatment (n = 675) was 22.8% at 3 years. A factor associated with synchronous and metachronous PM was diffuse type histology. Patients diagnosed with synchronous PM more often received systemic treatment than patients with metachronous PM (35% vs 18%, respectively, P < .001). Median overall survival was comparable between synchronous and metachronous PM (3.2 vs 2.3 months, respectively, P = .731). Approximately one third of all patients with gastric cancer are diagnosed with PM, either at primary diagnosis or during 3-year follow-up after potentially curative treatment. Patients with metachronous PM less often received systemic treatment than those with synchronous PM but survival was comparable between both groups. Future trials are warranted to detect gastric cancer at an earlier stage and to examine strategies that lower the risk of peritoneal dissemination. Also, specific treatment options for patients with gastric PM should be further investigated.

Evaluation of Short- and Long-Term Outcomes After Resection in Patients with Locally Advanced versus (Borderline) Resectable Pancreatic Cancer.

OBJECTIVE: This study aims to evaluate short- and long-term outcomes following pancreatectomy in patients with LAPC compared to (B)RPC patients. SUMMARY BACKGROUND DATA: Selected patients diagnosed with locally advanced pancreatic cancer (LAPC) are increasingly undergoing resection following induction chemotherapy. To evaluate the benefit of this treatment approach, it is helpful to compare outcomes in resected patients with primary LAPC to outcomes in resected patients with primary (borderline) resectable pancreatic cancer ((B)RPC). METHODS: Two prospectively maintained nationwide databases were used for this study. Patients with (B)RPC undergoing upfront tumor resection and patients with resected LAPC after induction therapy were included. Outcomes were postoperative pancreas-specific complications, 90-day mortality, pathological outcomes, disease-free interval (DFI), and overall survival (OS). RESULTS: Overall, 879 patients were included; 103 with LAPC (12%) and 776 with (B)RPC (88%). LAPC patients had a lower WHO performance score and CACI. Postoperative pancreas-specific complications were comparable between groups, except delayed gastric emptying grade C, which occurred more often in LAPC patients (9% vs. 3%, P=0.03). Ninety-day mortality was comparable. About half of the patients in both groups (54% in LAPC vs. 48% in (B)RPC), P=0.21) had a radical resection (R0). DFI was 13 months in both groups (P=0.12) and OS from date of diagnosis was 24 months in LAPC patients and 19 months in (B)RPC patients (P=0.34). CONCLUSIONS: In our nationwide prospective databases, pancreas-specific complications, mortality and survival in patients with LAPC following pancreatectomy are comparable with those undergoing resection for (B)RPC. These outcomes suggest that postoperative morbidity and mortality after tumor resection in carefully selected patients with LAPC are acceptable.

Minimum and Optimal CA19-9 Response After Two Months Induction Chemotherapy in Patients With Locally Advanced Pancreatic Cancer: A Nationwide Multicenter Study.

OBJECTIVE: This nationwide multicenter study aimed to define clinically relevant thresholds of relative serum CA19-9 response after 2 months of induction chemotherapy in patients with locally advanced pancreatic cancer (LAPC). BACKGROUND: CA19-9 is seen as leading biomarker for response evaluation in patients with LAPC, but early clinically useful cut-offs are lacking. METHODS: All consecutive patients with LAPC after 4 cycles (m)FOLFIRINOX or 2 cycles gemcitabine-nab-paclitaxel induction chemotherapy (±radiotherapy) with CA19-9 ≥5 U/mL at baseline were analyzed (2015-2019). The association of CA19-9 response with median OS (mOS) was evaluated for different CA19-9 cut-off points. Minimum and optimal CA19-9 response were established via log-rank test. Predictors for OS were analyzed using COX regression analysis. RESULTS: Overall, 212 patients were included, of whom 42 (19.8%) underwent resection. Minimum CA19-9 response demonstrating a clinically significant median OS difference (12.7 vs. 19.6 months) was seen at ≥40% CA19-9 decrease. The optimal cutoff for CA19-9 response was ≥60% decrease (21.7 vs. 14.0 mo, P =0.021). Only for patients with elevated CA19-9 levels at baseline (n=184), CA19-9 decrease ≥60% [hazard ratio (HR)=0.59, 95% CI, 0.36-0.98, P =0.042] was independently associated with prolonged OS, as were SBRT (HR=0.42, 95% CI, 0.25-0.70; P =0.001), and resection (HR=0.25, 95% CI, 0.14-0.46, P <0.001), and duration of chemotherapy (HR=0.75, 95% CI, 0.69-0.82, P <0.001). CONCLUSIONS: CA19-9 decrease of ≥60% following induction chemotherapy as optimal response cut-off in patients with LAPC is an independent predictor for OS when CA19-9 is increased at baseline. Furthermore, ≥40% is the minimum cut-off demonstrating survival benefit. These cut-offs may be used when discussing treatment strategies during early response evaluation.

Predicting Long-term Disease-free Survival After Resection of Pancreatic Ductal Adenocarcinoma: A Nationwide Cohort Study.

OBJECTIVE: To develop a prediction model for long-term (≥5 years) disease-free survival (DFS) after the resection of pancreatic ductal adenocarcinoma (PDAC). BACKGROUND: Despite high recurrence rates, ~10% of patients have long-term DFS after PDAC resection. A model to predict long-term DFS may aid individualized prognostication and shared decision-making. METHODS: This nationwide cohort study included all consecutive patients who underwent PDAC resection in the Netherlands (2014-2016). The best-performing prognostic model was selected by Cox-proportional hazard analysis and Akaike's Information Criterion, presented by hazard ratios (HRs) with 95% confidence intervals (CIs). Internal validation was performed, and discrimination and calibration indices were assessed. RESULTS: In all, 836 patients with a median follow-up of 67 months (interquartile range 51-79) were analyzed. Long-term DFS was seen in 118 patients (14%). Factors predictive of long-term DFS were low preoperative carbohydrate antigen 19-9 (logarithmic; HR 1.21; 95% CI 1.10-1.32), no vascular resection (HR 1.33; 95% CI 1.12-1.58), T1 or T2 tumor stage (HR 1.52; 95% CI 1.14-2.04, and HR 1.17; 95% CI 0.98-1.39, respectively), well/moderate tumor differentiation (HR 1.44; 95% CI 1.22-1.68), absence of perineural and lymphovascular invasion (HR 1.42; 95% CI 1.11-1.81 and HR 1.14; 95% CI 0.96-1.36, respectively), N0 or N1 nodal status (HR 1.92; 95% CI 1.54-2.40, and HR 1.33; 95% CI 1.11-1.60, respectively), R0 resection margin status (HR 1.25; 95% CI 1.07-1.46), no major complications (HR 1.14; 95% CI 0.97-1.35) and adjuvant chemotherapy (HR 1.74; 95% CI 1.47-2.06). Moderate performance (concordance index 0.68) with adequate calibration (slope 0.99) was achieved. CONCLUSIONS: The developed prediction model, readily available at www.pancreascalculator.com, can be used to estimate the probability of long-term DFS after resection of pancreatic ductal adenocarcinoma.

Perineural Invasion is an Important Prognostic Factor in Patients With Radically Resected (R0) and Node-negative (pN0) Pancreatic Cancer.

OBJECTIVE: To investigate the association between perineural invasion (PNI) and overall survival (OS) in a nationwide cohort of patients with resected pancreatic ductal adenocarcinoma (PDAC), stratified for margin negative (R0) or positive (R1) resection and absence or presence of lymph node metastasis (pN0 or pN1-N2, respectively). BACKGROUND: Patients with R0 and pN0 resected PDAC have a relatively favorable prognosis. As PNI is associated with worse OS, this might be a useful factor to provide further prognostic information for patients counselling. METHODS: A nationwide observational cohort study was performed including all patients who underwent PDAC resection in the Netherlands (2014-2019) with complete information on relevant pathological features (PNI, R status, and N status). OS was assessed using Kaplan-Meier curves, and Cox-proportional hazard analyses were performed to calculate hazard ratio's (HR) with corresponding 95% confidence intervals (CI). RESULTS: In total, 1630 patients were included with a median follow-up of 43 (interquartile range 33-58) months. PNI was independently associated with worse OS in both R0 patients (HR 1.49 [95%CI 1.18-1.88]; P<0.001) and R1 patients (HR 1.39 [95% CI 1.06-1.83]; P=0.02), as well as in pN0 patients (HR 1.75 [95%CI 1.27-2.41]; P<0.001) and pN1-N2 patients (HR 1.35 [95% CI 1.10-1.67]; P<0.01). In 315 patients with R0N0, multivariable analysis showed that PNI was the strongest predictor of OS (HR 2.24 [95% CI 1.52-3.30]; P<0.001). CONCLUSION: PNI is strongly associated with worse survival in patients with resected PDAC, in particular in patients with relatively favorable pathological features. These findings may aid patient stratification and counselling and help guide treatment strategies.

Towards Equal Access to Cytoreductive Surgery with Hyperthermic Intraperitoneal Chemotherapy and Survival in Patients with Isolated Colorectal Peritoneal Metastases: A Nationwide Population-Based Study.

BACKGROUND: Before 2016, patients with isolated synchronous colorectal peritoneal metastases (PMCRC) diagnosed in expert centers had a higher odds of undergoing cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS-HIPEC) and better overall survival (OS) than those diagnosed in referring centers. Nationwide efforts were initiated to increase awareness and improve referral networks. METHODS: This nationwide study aimed to evaluate whether the between-center differences in odds of undergoing CRS-HIPEC and OS have reduced since these national efforts were initiated. All patients with isolated synchronous PMCRC diagnosed between 2009 and 2021 were identified from the Netherlands Cancer Registry. Associations between hospital of diagnosis and the odds of undergoing CRS-HIPEC, as well as OS, were assessed using multilevel multivariable regression analyses for two periods (2009-2015 and 2016-2021). RESULTS: In total, 3948 patients were included. The percentage of patients undergoing CRS-HIPEC increased from 17.2% in 2009-2015 (25.4% in expert centers, 16.5% in referring centers), to 23.4% in 2016-2021 (30.2% in expert centers, 22.6% in referring centers). In 2009-2015, compared with diagnosis in a referring center, diagnosis in a HIPEC center showed a higher odds of undergoing CRS-HIPEC (odds ratio [OR] 1.64, 95% confidence interval [CI] 1.02-2.67) and better survival (hazard ratio [HR] 0.80, 95% CI 0.66-0.96). In 2016-2021, there were no differences in the odds of undergoing CRS-HIPEC between patients diagnosed in HIPEC centers versus referring centers (OR 1.27, 95% CI 0.76-2.13) and survival (HR 1.00, 95% CI 0.76-1.32). CONCLUSION: Previously observed differences in odds of undergoing CRS-HIPEC were no longer present. Increased awareness and the harmonization of treatment for PMCRC may have contributed to equal access to care and a similar chance of survival at a national level.

Nationwide Use and Outcome of Surgery for Locally Advanced Pancreatic Cancer Following Induction Chemotherapy.

BACKGROUND: Several international high-volume centers have reported good outcomes after resection of locally advanced pancreatic cancer (LAPC) following chemo(radio)therapy, but it is unclear how this translates to nationwide clinical practice and outcome. This study aims to assess the nationwide use and outcome of resection of LAPC following induction chemo(radio)therapy. PATIENTS AND METHODS: A multicenter retrospective study including all patients who underwent resection for LAPC following chemo(radio)therapy in all 16 Dutch pancreatic surgery centers (2014-2020), registered in the mandatory Dutch Pancreatic Cancer Audit. LAPC is defined as arterial involvement > 90° and/or portomesenteric venous > 270° involvement or occlusion. RESULTS: Overall, 142 patients underwent resection for LAPC, of whom 34.5% met the 2022 National Comprehensive Cancer Network criteria. FOLFIRINOX was the most commonly (93.7%) used chemotherapy [median 5 cycles (IQR 4-8)]. Venous and arterial resections were performed in 51.4% and 14.8% of patients. Most resections (73.9%) were performed in high-volume centers (i.e., ≥ 60 pancreatoduodenectomies/year). Overall median volume of LAPC resections/center was 4 (IQR 1-7). In-hospital/30-day major morbidity was 37.3% and 90-day mortality was 4.2%. Median OS from diagnosis was 26 months (95% CI 23-28) and 5-year OS 18%. Surgery in high-volume centers [HR = 0.542 (95% CI 0.318-0.923)], ypN1-2 [HR = 3.141 (95% CI 1.886-5.234)], and major morbidity [HR = 2.031 (95% CI 1.272-3.244)] were associated with OS. CONCLUSIONS: Resection of LAPC following chemo(radio)therapy is infrequently performed in the Netherlands, albeit with acceptable morbidity, mortality, and OS. Given these findings, a structured nationwide approach involving international centers of excellence would be needed to improve selection of patients with LAPC for surgical resection following induction therapy.

The Value of Biological and Conditional Factors for Staging of Patients with Resectable Pancreatic Cancer Undergoing Upfront Resection: A Nationwide Analysis.

BACKGROUND: Novel definitions suggest that resectability status for pancreatic ductal adenocarcinoma (PDAC) should be assessed beyond anatomical criteria, considering both biological and conditional factors. This has, however, yet to be validated on a nationwide scale. This study evaluated the prognostic value of biological and conditional factors for staging of patients with resectable PDAC. PATIENTS AND METHODS: A nationwide observational cohort study was performed, including all consecutive patients who underwent upfront resection of National Comprehensive Cancer Network resectable PDAC in the Netherlands (2014-2019) with complete information on preoperative carbohydrate antigen (CA) 19-9 and Eastern Cooperative Oncology Group (ECOG) performance status. PDAC was considered biologically unfavorable (RB+) if CA19-9 ≥ 500 U/mL and favorable (RB-) otherwise. ECOG ≥ 2 was considered conditionally unfavorable (RC+) and favorable otherwise (RC-). Overall survival (OS) was assessed using Kaplan-Meier and Cox-proportional hazard analysis, presented as hazard ratios (HRs) with 95% confidence interval (CI). RESULTS: Overall, 688 patients were analyzed with a median overall survival (OS) of 20 months (95% CI 19-23). OS was 14 months (95% CI 10 months-median not reached) in 20 RB+C+ patients (3%; HR 1.61, 95% CI 0.86-2.70), 13 months (95% CI 11-15) in 156 RB+C- patients (23%; HR 1.86, 95% CI 1.50-2.31), and 21 months (95% CI 12-41) in 47 RB-C+ patients (7%; HR 1.14, 95% CI 0.80-1.62) compared with 24 months (95% CI 22-27) in 465 patients with RB-C- PDAC (68%; reference). CONCLUSIONS: Survival after upfront resection of anatomically resectable PDAC is worse in patients with CA19-9 ≥ 500 U/mL, while performance status had no impact. This supports consideration of CA19-9 in preoperative staging of resectable PDAC.

Early experience with robotic pancreatoduodenectomy versus open pancreatoduodenectomy: nationwide propensity-score-matched analysis.

BACKGROUND: Although robotic pancreatoduodenectomy has shown promising outcomes in experienced high-volume centres, it is unclear whether implementation on a nationwide scale is safe and beneficial. The aim of this study was to compare the outcomes of the early experience with robotic pancreatoduodenectomy versus open pancreatoduodenectomy in the Netherlands. METHODS: This was a nationwide retrospective cohort study of all consecutive patients who underwent robotic pancreatoduodenectomy or open pancreatoduodenectomy who were registered in the mandatory Dutch Pancreatic Cancer Audit (18 centres, 2014-2021), starting from the first robotic pancreatoduodenectomy procedure per centre. The main endpoints were major complications (Clavien-Dindo grade greater than or equal to III) and in-hospital/30-day mortality. Propensity-score matching (1 : 1) was used to minimize selection bias. RESULTS: Overall, 701 patients who underwent robotic pancreatoduodenectomy and 4447 patients who underwent open pancreatoduodenectomy were included. Among the eight centres that performed robotic pancreatoduodenectomy, the median robotic pancreatoduodenectomy experience was 86 (range 48-149), with a 7.3% conversion rate. After matching (698 robotic pancreatoduodenectomy patients versus 698 open pancreatoduodenectomy control patients), no significant differences were found in major complications (40.3% versus 36.2% respectively; P = 0.186), in-hospital/30-day mortality (4.0% versus 3.1% respectively; P = 0.326), and postoperative pancreatic fistula grade B/C (24.9% versus 23.5% respectively; P = 0.578). Robotic pancreatoduodenectomy was associated with a longer operating time (359 min versus 301 min; P < 0.001), less intraoperative blood loss (200 ml versus 500 ml; P < 0.001), fewer wound infections (7.4% versus 12.2%; P = 0.008), and a shorter hospital stay (11 days versus 12 days; P < 0.001). Centres performing greater than or equal to 20 robotic pancreatoduodenectomies annually had a lower mortality rate (2.9% versus 7.3%; P = 0.009) and a lower conversion rate (6.3% versus 11.2%; P = 0.032). CONCLUSION: This study indicates that robotic pancreatoduodenectomy was safely implemented nationwide, without significant differences in major morbidity and mortality compared with matched open pancreatoduodenectomy patients. Randomized trials should be carried out to verify these findings and confirm the observed benefits of robotic pancreatoduodenectomy versus open pancreatoduodenectomy.

The impact of hospital experience in bariatric surgery on short-term outcomes after minimally invasive esophagectomy: a nationwide analysis.

BACKGROUND: Minimally invasive esophagectomy (MIE) is a technically challenging procedure with a substantial learning curve. Composite volume of upper gastrointestinal (upper GI) procedures for cancer has been previously linked to postoperative outcomes. This study aimed to investigate an association between hospital experience in bariatric surgery and short-term outcomes in MIE. METHOD: Data on esophagectomy patients between 2016 and 2020 were collected from the Dutch Upper Gastrointestinal Cancer Audit, a mandatory nationwide registry. Hospitals were categorized as bariatric or non-bariatric. Multivariable logistic regression investigated short-term postoperative outcomes, adjusting for case mix. RESULTS: Of 3371 patients undergoing esophagectomy in sixteen hospitals, 2450 (72.7%) underwent MIE. Bariatric hospitals (N = 6) accounted for 1057 (43.1%) MIE. Annual volume of bariatric procedures was median 523 and esophagectomies 42. In non-bariatric hospitals, volume of esophagectomies was median 52 (P = 0.145). Overall postoperative complication rate was lower in bariatric hospitals (59.2% vs. 65.9%, P < 0.001). Bariatric hospitals were associated with a reduced risk of overall complications (aOR 0.76 [95% CI 0.62-0.92]), length of hospital (aOR 0.79 [95% CI 0.65-0.95]), and ICU stay (aOR 0.81 [95% CI 0.67-0.98]) after MIE. Surgical radicality (R0) did not differ. Lymph node yield (≥ 15) was lower in bariatric hospitals (90.0% vs. 94.7%, P < 0.001). Over the years, several short-term outcomes improved in bariatric hospitals compared to non-bariatric hospitals. CONCLUSION: In this nationwide analysis, there was an association between bariatric hospitals and improved short-term outcomes after MIE. Characteristics of bariatric hospitals that could explain this phenomenon and whether this translates to other upper GI procedures may be warranted to identify.

Postoperative circadian patterns in wearable sensor measured heart rate: a prospective observational study.

PURPOSE: This study aimed to describe the 24-hour cycle of wearable sensor-obtained heart rate in patients with deterioration-free recovery and to compare it with patients experiencing postoperative deterioration. METHODS: A prospective observational trial was performed in patients following bariatric or major abdominal cancer surgery. A wireless accelerometer patch (Healthdot) continuously measured postoperative heart rate, both in the hospital and after discharge, for a period of 14 days. The circadian pattern, or diurnal rhythm, in the wearable sensor-obtained heart rate was described using peak, nadir and peak-nadir excursions. RESULTS: The study population consisted of 137 bariatric and 100 major abdominal cancer surgery patients. In the latter group, 39 experienced postoperative deterioration. Both surgery types showed disrupted diurnal rhythm on the first postoperative days. Thereafter, the bariatric group had significantly lower peak heart rates (days 4, 7-12, 14), lower nadir heart rates (days 3-14) and larger peak-nadir excursions (days 2, 4-14). In cancer surgery patients, significantly higher nadir (days 2-5) and peak heart rates (days 2-3) were observed prior to deterioration. CONCLUSIONS: The postoperative diurnal rhythm of heart rate is disturbed by different types of surgery. Both groups showed recovery of diurnal rhythm but in patients following cancer surgery, both peak and nadir heart rates were higher than in the bariatric surgery group. Especially nadir heart rate was identified as a potential prognostic marker for deterioration after cancer surgery.

Cytoreductive surgery with or without hyperthermic intraperitoneal chemotherapy in patients with advanced ovarian cancer (OVHIPEC-1): final survival analysis of a randomised, controlled, phase 3 trial.

BACKGROUND: The OVHIPEC-1 trial previously showed that the addition of hyperthermic intraperitoneal chemotherapy (HIPEC) to interval cytoreductive surgery resulted in improved progression-free and overall survival compared with cytoreductive surgery alone at 4·7 years of follow-up in patients with stage III epithelial ovarian cancer who were ineligible for primary cytoreduction. We report the final survival outcomes after 10 years of follow-up. METHODS: In this open-label, randomised, controlled, phase 3 trial, patients with primary epithelial stage III ovarian cancer were recruited at eight HIPEC centres in the Netherlands and Belgium. Patients were eligible if they were aged 18-76 years, had not progressed during at least three cycles of neoadjuvant carboplatin plus paclitaxel, had a WHO performance status score of 0-2, normal blood counts, and adequate renal function. Patients were randomly assigned (1:1) to undergo interval cytoreductive surgery without HIPEC (surgery group) or with HIPEC (100 mg/m2 cisplatin; surgery-plus-HIPEC group). Randomisation was done centrally by minimisation with a masked web-based allocation procedure at the time of surgery when residual disease smaller than 10 mm diameter was anticipated, and was stratified by institution, previous suboptimal cytoreductive surgery, and number of abdominal regions involved. The primary endpoint was progression-free survival and a secondary endpoint was overall survival, analysed in the intention-to-treat population (ie, all randomly assigned patients). This study is registered with ClinicalTrials.gov, NCT00426257, and is closed. FINDINGS: Between April 1, 2007, and April 30, 2016, 245 patients were enrolled and followed up for a median of 10·1 years (95% CI 8·4-12·9) in the surgery group (n=123) and 10·4 years (95% CI 9·5-13·3) in the surgery-plus-HIPEC group (n=122). Recurrence, progression, or death occurred in 114 (93%) patients in the surgery group (median progression-free survival 10·7 months [95% CI 9·6-12·0]) and 109 (89%) patients in the surgery-plus-HIPEC group (14·3 months [12·0-18·5]; hazard ratio [HR] 0·63 [95% CI 0·48-0·83], stratified log-rank p=0·0008). Death occurred in 108 (88%) patients in the surgery group (median overall survival 33·3 months [95% CI 29·0-39·1]) and 100 (82%) patients in the surgery-plus-HIPEC group (44·9 months [95% CI 38·6-55·1]; HR 0·70 [95% CI 0·53-0·92], stratified log-rank p=0·011). INTERPRETATION: These updated survival results confirm the long-term survival benefit of HIPEC in patients with primary stage III epithelial ovarian cancer undergoing interval cytoreductive surgery. FUNDING: Dutch Cancer Foundation (KWF Kankerbestrijding).

A propensity score-matched analysis of oncological outcome after systemic therapy for stage IV colorectal cancer: Impact of synchronous ovarian metastases.

The reported incidence of synchronous and metachronous ovarian metastases (OM) from colorectal cancer (CRC) is ~3.4%. OM from CRC are often considered sanctuary sites due to their lower sensitivity to systemic treatment. It has thus been hypothesized that the presence of OM decreases overall survival. Therefore, the purpose of our study was to evaluate the impact of synchronous OM on overall survival in female patients with stage IV CRC treated with systemic therapy alone with palliative intent. The present study used data from the Netherlands Cancer Registry and included female CRC patients with synchronous systemic metastases who were treated with systemic therapy between 2008 and 2018. A subsample was created using propensity score matching to create comparable groups. Propensity scores were determined using a logistic regression model in which the dependent variable was the presence of OM and the independent variables were the variables that differed significantly between both groups. Our study included 5253 patients with stage IV CRC that received systemic therapy. Among these patients, 161 (3%) had OM while 5092 (97%) had extra-ovarian metastases only. Three-year overall survival rates did not show a significant difference between patients with OM compared to patients without ovarian metastases. Moreover, the propensity score-matched analysis showed that the presence of OM in patients treated with systemic therapy for stage IV CRC disease was not associated with decreased 3-year overall survival. However, the results of the present study should be interpreted with caution, due to its observational character and used selection criteria.

Serum levels of iCAF-derived osteoglycin predict favorable outcome in pancreatic cancer.

Pancreatic ductal adenocarcinoma (PDAC) is characterized by abundant stroma, the main cellular constituents of which are cancer-associated fibroblasts (CAFs). Stroma-targeting agents have been proposed to improve the poor outcome of current treatments. However, clinical trials using these agents showed disappointing results. Heterogeneity in the PDAC CAF population was recently delineated demonstrating that both tumor-promoting and tumor-suppressive activities co-exist in the stroma. Here, we aimed to identify biomarkers for the CAF population that contribute to a favorable outcome. RNA-sequencing reads from patient-derived xenografts (PDXs) were mapped to the human and mouse genome to allocate the expression of genes to the tumor or stroma. Survival meta-analysis for stromal genes was performed and applied to human protein atlas data to identify circulating biomarkers. The candidate protein was perturbed in co-cultures and assessed in existing and novel single-cell gene expression analysis from control, pancreatitis, pancreatitis-recovered and PDAC mouse models. Serum levels of the candidate biomarker were measured in two independent cohorts totaling 148 PDAC patients and related them to overall survival. Osteoglycin (OGN) was identified as a candidate serum prognostic marker. Single-cell analysis indicated that Ogn is derived from a subgroup of inflammatory CAFs. Ogn-expressing fibroblasts are distinct from resident healthy pancreatic stellate cells and arise during pancreatitis. Serum OGN levels were prognostic for favorable overall survival in two independent PDAC cohorts (HR = 0.47, P = .042 and HR = 0.53, P = .006). Altogether, we conclude that high circulating OGN levels inform on a previously unrecognized subgroup of CAFs and predict favorable outcomes in resectable PDAC.

Chyle Leak After Pancreatoduodenectomy: Clinical Impact and Risk Factors in a Nationwide Analysis.

OBJECTIVE: The aim of this study was to assess the clinical impact and risk factors of chyle leak (CL). BACKGROUND: In 2017, the International Study Group for Pancreatic Surgery (ISGPS) published the consensus definition of CL. Multicenter series validating this definition are lacking and previous studies investigating risk factors have used different definitions and showed heterogeneous results. METHODS: This observational cohort study included all consecutive patients after pancreatoduodenectomy in all 19 centers in the mandatory nationwide Dutch Pancreatic Cancer Audit (2017-2019). The primary endpoint was CL (ISGPS grade B/C). Multivariable logistic regression analyses were performed. RESULTS: Overall, 2159 patients after pancreatoduodenectomy were included. The rate of CL was 7.0% (n=152), including 6.9% (n=150) grade B and 0.1% (n=2) grade C. CL was independently associated with a prolonged hospital stay [odds ratio (OR)=2.84, 95% confidence interval (CI): 1.85-4.36, P <0.001] but not with mortality (OR=0.3, 95% CI: 0.0-2.3, P =0.244). In multivariable analyses, independent predictors for CL were vascular resection (OR=2.1, 95% CI: 1.4-3.2, P <0.001) and open surgery (OR=3.5, 95% CI: 1.7-7.2, P =0.001). The number of resected lymph nodes and aortocaval lymph node sampling were not identified as predictors in multivariable analysis. CONCLUSIONS: In this nationwide analysis, the rate of ISGPS grade B/C CL after pancreatoduodenectomy was 7.0%. Although CL is associated with a prolonged hospital stay, the clinical impact is relatively minor in the vast majority (>98%) of patients. Vascular resection and open surgery are predictors of CL.

Video Grading of Pancreatic Anastomoses During Robotic Pancreatoduodenectomy to Assess Both Learning Curve and the Risk of Pancreatic Fistula: A Post Hoc Analysis of the LAELAPS-3 Training Program.

OBJECTIVE: To assess the learning curve of pancreaticojejunostomy during robotic pancreatoduodenectomy (RPD) and to predict the risk of postoperative pancreatic fistula (POPF) by using the objective structured assessment of technical skills (OSATS), taking the fistula risk into account. BACKGROUND: RPD is a challenging procedure that requires extensive training and confirmation of adequate surgical performance. Video grading, modified for RPD, of the pancreatic anastomosis could assess the learning curve of RPD and predict the risk of POPF. METHODS: Post hoc assessment of patients prospectively included in 4 Dutch centers in a nationwide LAELAPS-3 training program for RPD. Video grading of the pancreaticojejunostomy was performed by 2 graders using OSATS (attainable score: 12-60). The main outcomes were the combined OSATS of the 2 graders and POPF (grade B/C). Cumulative sum analyzed a turning point in the learning curve for surgical skill. Logistic regression determined the cutoff for OSATS. Patients were categorized for POPF risk (ie, low, intermediate, and high) based on the updated alternative fistula risk scores. RESULTS: Videos from 153 pancreatic anastomoses were included. Median OSATS score was 48 (interquartile range: 41-52) points and with a turning point at 33 procedures. POPF occurred in 39 patients (25.5%). An OSATS score below 49, present in 77 patients (50.3%), was associated with an increased risk of POPF (odds ratio: 4.01, P =0.004). The POPF rate was 43.6% with OSATS < 49 versus 15.8% with OSATS ≥49. The updated alternative fistula risk scores category "soft pancreatic texture" was the second strongest prognostic factor of POPF (odds ratio: 3.37, P =0.040). Median cumulative surgical experience was 17 years (interquartile range: 8-21). CONCLUSIONS: Video grading of the pancreatic anastomosis in RPD using OSATS identified a learning curve and a reduced risk of POPF in case of better surgical performance. Video grading may provide a valid method to surgical training, quality control, and improvement.

Fistula Risk Score for Auditing Pancreatoduodenectomy: The Auditing-FRS.

OBJECTIVE: To develop a fistula risk score for auditing, to be able to compare postoperative pancreatic fistula (POPF) after pancreatoduodenectomy among hospitals. BACKGROUND: For proper comparisons of outcomes in surgical audits, case-mix variation should be accounted for. METHODS: This study included consecutive patients after pancreatoduodenectomy from the mandatory nationwide Dutch Pancreatic Cancer Audit. Derivation of the score was performed with the data from 2014 to 2018 and validation with 2019 to 2020 data. The primary endpoint of the study was POPF (grade B or C). Multivariable logistic regression analysis was performed for case-mix adjustment of known risk factors. RESULTS: In the derivation cohort, 3271 patients were included, of whom 479 (14.6%) developed POPF. Male sex [odds ratio (OR)=1.34; 95% confidence interval (CI): 1.09-1.66], higher body mass index (OR=1.07; 95% CI: 1.05-1.10), a final diagnosis other than pancreatic ductal adenocarcinoma/pancreatitis (OR=2.41; 95% CI: 1.90-3.06), and a smaller duct diameter (OR=1.43/mm decrease; 95% CI: 1.32-1.55) were independently associated with POPF. Diabetes mellitus (OR=0.73; 95% CI: 0.55-0.98) was independently associated with a decreased risk of POPF. Model discrimination was good with a C -statistic of 0.73 in the derivation cohort and 0.75 in the validation cohort (n=913). Hospitals differed in particular in the proportion of pancreatic ductal adenocarcinoma/pancreatitis patients, ranging from 36.0% to 58.1%. The observed POPF risk per center ranged from 2.9% to 25.4%. The expected POPF rate based on the 5 risk factors ranged from 11.6% to 18.0% among hospitals. CONCLUSIONS: The auditing fistula risk score was successful in case-mix adjustment and enables fair comparisons of POPF rates among hospitals.

Early Recurrence After Resection of Locally Advanced Pancreatic Cancer Following Induction Therapy: An International Multicenter Study.

OBJECTIVE: To establish an evidence-based cutoff and predictors for early recurrence in patients with resected locally advanced pancreatic cancer (LAPC). BACKGROUND: It is unclear how many and which patients develop early recurrence after LAPC resection. Surgery in these patients is probably of little benefit. METHODS: We analyzed all consecutive patients undergoing resection of LAPC after induction chemotherapy who were included in prospective databases in The Netherlands (2015-2019) and the Johns Hopkins Hospital (2016-2018). The optimal definition for "early recurrence" was determined by the post-recurrence survival (PRS). Patients were compared for overall survival (OS). Predictors for early recurrence were evaluated using logistic regression analysis. RESULTS: Overall, 168 patients were included. After a median follow-up of 28 months, recurrence was observed in 118 patients (70.2%). The optimal cutoff for recurrence-free survival to differentiate between early (n=52) and late recurrence (n=66) was 6 months ( P <0.001). OS was 8.4 months [95% confidence interval (CI): 7.3-9.6] in the early recurrence group (n=52) versus 31.1 months (95% CI: 25.7-36.4) in the late/no recurrence group (n=116) ( P <0.001). A preoperative predictor for early recurrence was postinduction therapy carbohydrate antigen (CA) 19-9≥100 U/mL [odds ratio (OR)=4.15, 95% CI: 1.75-9.84, P =0.001]. Postoperative predictors were poor tumor differentiation (OR=4.67, 95% CI: 1.83-11.90, P =0.001) and no adjuvant chemotherapy (OR=6.04, 95% CI: 2.43-16.55, P <0.001). CONCLUSIONS: Early recurrence was observed in one third of patients after LAPC resection and was associated with poor survival. Patients with post-induction therapy CA 19-9 ≥100 U/mL, poor tumor differentiation and no adjuvant therapy were especially at risk. This information is valuable for patient counseling before and after resection of LAPC.

Risk Models for Developing Pancreatic Fistula After Pancreatoduodenectomy: Validation in a Nationwide Prospective Cohort.

OBJECTIVE: To evaluate the performance of published fistula risk models by external validation, and to identify independent risk factors for postoperative pancreatic fistula (POPF). BACKGROUND: Multiple risk models have been developed to predict POPF after pancreatoduodenectomy. External validation in high-quality prospective cohorts is, however, lacking or only performed for individual models. METHODS: A post hoc analysis of data from the stepped-wedge cluster cluster-randomized Care After Pancreatic Resection According to an Algorithm for Early Detection and Minimally Invasive Management of Pancreatic Fistula versus Current Practice (PORSCH) trial was performed. Included were all patients undergoing pancreatoduodenectomy in the Netherlands (January 2018-November 2019). Risk models on POPF were identified by a systematic literature search. Model performance was evaluated by calculating the area under the receiver operating curves (AUC) and calibration plots. Multivariable logistic regression was performed to identify independent risk factors associated with clinically relevant POPF. RESULTS: Overall, 1358 patients undergoing pancreatoduodenectomy were included, of whom 341 patients (25%) developed clinically relevant POPF. Fourteen risk models for POPF were evaluated, with AUCs ranging from 0.62 to 0.70. The updated alternative fistula risk score had an AUC of 0.70 (95% confidence intervals [CI]: 0.69-0.72). The alternative fistula risk score demonstrated an AUC of 0.70 (95% CI: 0.689-0.71), whilst an AUC of 0.70 (95% CI: 0.699-0.71) was also found for the model by Petrova and colleagues. Soft pancreatic texture, pathology other than pancreatic ductal adenocarcinoma or chronic pancreatitis, small pancreatic duct diameter, higher body mass index, minimally invasive resection and male sex were identified as independent predictors of POPF. CONCLUSION: Published risk models predicting clinically relevant POPF after pancreatoduodenectomy have a moderate predictive accuracy. Their clinical applicability to identify high-risk patients and guide treatment strategies is therefore questionable.

Outcome of Pancreatic Surgery During the First 6 Years of a Mandatory Audit Within the Dutch Pancreatic Cancer Group.

OBJECTIVE: To describe outcome after pancreatic surgery in the first 6 years of a mandatory nationwide audit. BACKGROUND: Within the Dutch Pancreatic Cancer Group, efforts have been made to improve outcome after pancreatic surgery. These include collaborative projects, clinical auditing, and implementation of an algorithm for early recognition and management of postoperative complications. However, nationwide changes in outcome over time have not yet been described. METHODS: This nationwide cohort study included consecutive patients after pancreatoduodenectomy (PD) and distal pancreatectomy from the mandatory Dutch Pancreatic Cancer Audit (January 2014-December 2019). Patient, tumor, and treatment characteristics were compared between 3 time periods (2014-2015, 2016-2017, and 2018-2019). Short-term surgical outcome was investigated using multilevel multivariable logistic regression analyses. Primary endpoints were failure to rescue (FTR) and in-hospital mortality. RESULTS: Overall, 5345 patients were included, of whom 4227 after PD and 1118 after distal pancreatectomy. After PD, FTR improved from 13% to 7.4% [odds ratio (OR) 0.64, 95% confidence interval (CI) 0.50-0.80, P <0.001] and in-hospital mortality decreased from 4.1% to 2.4% (OR 0.68, 95% CI 0.54-0.86, P =0.001), despite operating on more patients with age >75 years (18%-22%, P =0.006), American Society of Anesthesiologists score ≥3 (19%-31%, P <0.001) and Charlson comorbidity score ≥2 (24%-34%, P <0.001). The rates of textbook outcome (57%-55%, P =0.283) and major complications remained stable (31%-33%, P =0.207), whereas complication-related intensive care admission decreased (13%-9%, P =0.002). After distal pancreatectomy, improvements in FTR from 8.8% to 5.9% (OR 0.65, 95% CI 0.30-1.37, P =0.253) and in-hospital mortality from 1.6% to 1.3% (OR 0.88, 95% CI 0.45-1.72, P =0.711) were not statistically significant. CONCLUSIONS: During the first 6 years of a nationwide audit, in-hospital mortality and FTR after PD improved despite operating on more high-risk patients. Several collaborative efforts may have contributed to these improvements.