Borderline Resectable Pancreatic Cancer Research Articles

Evidence and Future Perspectives for Neoadjuvant Therapy for Resectable and Borderline Resectable Pancreatic Cancer: A Scoping Review

Pancreatic cancer (PC) is a lethal disease that requires innovative therapeutic approaches to enhance the survival outcomes. Neoadjuvant treatment (NAT) has gained attention for resectable and borderline resectable PC, offering improved resection rates and enabling early intervention and patient selection. Several retrospective studies have validated its efficacy. However, previous studies have lacked intention-to-treat analyses and appropriate resectability classifications. Randomized comparative trials may help to enhance the clinical applicability of evidence. Therefore, after searching the MEDLINE database, this scoping review presents a comprehensive summary of the evidence from published (n = 14) and ongoing (n = 12) randomized Phase II and III trials. Diverse regimens and their outcomes were explored for both resectable and borderline resectable PC. While some trials have supported the efficacy of NAT, others have demonstrated no clear survival benefits for patients with resectable PC. The utility of NAT has been confirmed in patients with borderline resectable PC, but the optimal regimens remain debatable. Ongoing trials are investigating novel regimens, including immunotherapy, thereby highlighting the dynamic landscape of PC treatment. Studies should focus on biomarker identification, which may enable precision in oncology. Future endeavors aim to refine treatment strategies, guided by precision oncology.

The Oncological Stress Test of Neoadjuvant Therapy: A Systematic Review in Outcomes of Neoadjuvant Therapy Compared to Upfront Resection Approach for Borderline Resectable Pancreatic Adenocarcinoma.

Pancreatic adenocarcinoma, increasingly diagnosed in the United States, has a disheartening initial resection rate of 15%. Neoadjuvant therapy, particularly FOLFIRINOX and gemcitabine-based regimens, is gaining favor for its potential to improve resectability rates and achieving microscopically negative margins (R0) in borderline resectable cases, marked by intricate arterial or venous involvement. Despite surgery being the sole curative approach, actual benefit of neoadjuvant therapy remains debatable. This study scrutinizes current literature on oncological outcomes post-resection of borderline resectable pancreatic cancer. A MEDLINE/PubMed search was conducted to systematically compare oncological outcomes of patients treated with either neoadjuvant therapy with intent of curative resection or an "upfront resection" approach. A total of 1293 studies were initially screened and 30 were included (n = 1714) in this analysis. All studies included data on outcomes of patients with borderline resectable pancreatic adenocarcinoma being treated with neoadjuvant therapy (n = 1387) or a resection-first approach (n = 356). Patients treated with neoadjuvant therapy underwent resection 52% of the time, achieving negative margins of 43% (n = 601). Approximately 77% of patients who received an upfront resection underwent a successful resection, with 39% achieving negative margins. Neoadjuvant therapy remains marginally efficacious in treatment of borderline resectable pancreatic adenocarcinoma, as patients undergo an operation and successful resection less often when treated with neoadjuvant therapy. Rates of curative resection are comparable, despite neoadjuvant therapy being a primary recommendation in borderline resectable cases and employed more often than upfront resection. Upfront resection may offer improved resection rates by intention-to-treat, which can provide more patients with paths to curative resection.

The preliminary analysis of lymphatic flow around the connective tissues surrounding SMA and SpA elucidates patients’ oncological condition in borderline-resectable pancreatic cancer

BackgroundIn pancreatic ductal adenocarcinoma (PDAC), invasion of connective tissues surrounding major arteries is a crucial prognostic factor after radical resection. However, why the connective tissues invasion is associated with poor prognosis is not well understood.Materials and methodsFrom 2018 to 2020, 25 patients receiving radical surgery for PDAC in our institute were enrolled. HyperEye Medical System (HEMS) was used to examine lymphatic flow from the connective tissues surrounding SMA and SpA and which lymph nodes ICG accumulated in was examined.ResultsHEMS imaging revealed ICG was transported down to the paraaortic area of the abdominal aorta along SMA. In pancreatic head cancer, 9 paraaortic lymph nodes among 14 (64.3%) were ICG positive, higher positivity than LN#15 (25.0%) or LN#18 (50.0%), indicating lymphatic flow around the SMA was leading directly to the paraaortic lymph nodes. Similarly, in pancreatic body and tail cancer, the percentage of ICG-positive LN #16a2 was very high, as was that of #8a, although that of #7 was only 42.9%.ConclusionsOur preliminary result indicated that the lymphatic flow along the connective tissues surrounding major arteries could be helpful in understanding metastasis and improving prognosis in BR-A pancreatic cancer.

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

This study aims to evaluate short- and long-term outcomes following pancreatectomy in patients with LAPC compared to (B)RPC patients. 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). 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). 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). 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.

Outcomes of 6-mm diameter fully covered self-expandable metal stents for preoperative biliary drainage in pancreatic cancer.

10-mm self-expandable metal stents (SEMSs) are commonly used for preoperative biliary drainage in pancreatic cancer. However, smaller diameter SEMSs have attracted attention with the attempt to reduce stent-related adverse events (AEs). We retrospectively analyzed consecutive borderline resectable pancreatic cancer patients who underwent neoadjuvant therapy and fully covered SEMS (FCSEMS) placement from April 2015 to May 2023. The primary outcome was stent-related non-event rate (NER), which was defined as the rate of completion of surgery without developing any preoperative events (recurrent biliary obstruction [RBO] or stent-related AEs). Secondary outcomes included stent-related AEs, causes of RBO, and cumulative incidence of RBO. Risk factors for pancreatitis, RBO, and stent migration were also examined. A total of 76 patients were included (6-mm group: 23; 10-mm group: 53). Stent-related NER (57% vs. 64%, p = 0.610), stent-related AEs (4% vs. 15%, p = 0.263), overall RBO rates (39% vs. 23%, p = 0.168), cumulative incidence of RBO (hazard ratio, 2.24; 95% confidence interval, 0.95-5.25; p = 0.065) were not significantly different between the two groups. Tumor involvement of the pancreatic duct was identified as a risk-reducing factor for pancreatitis, while an FCSEMS diameter of 6 mm was not identified as a risk factor for RBO and stent migration. Stent-related NER was not significantly affected by FCSEMS diameter. Further studies are needed to confirm the usefulness of 6-mm diameter FCSEMS for preoperative biliary drainagein patients with borderline resectable pancreatic cancer.

Abstract 1010: Feasibility of serial microbiome collection in a multi-site neoadjuvant pancreatic cancer clinical trial allowing for a diverse patient population

Abstract Background: Pancreatic cancer portends a very poor prognosis. It is the third leading cause of cancer deaths in the United States. African Americans have a 50- 90% increased incidence of pancreatic cancer in comparison to other racial groups. 20% of patients present with operable disease and will have a median overall survival of 2.5 years if able to undergo surgical resection. There is a desperate need to discover novel ways of treating pancreatic cancer. Understanding of the microbiome may be informative to overcoming chemotherapy resistance, toxicity and improving outcomes and disparities. The aim of this study is to (1) identify changes in the microbiota during neoadjuvant treatment of pancreatic ductal adenocarcinoma that correlate with treatment response and (2) identify changes in the microbiota during neoadjuvant treatment of pancreatic ductal adenocarcinoma that correlate with treatment toxicity in a diverse patient population. Methods: Patients with resectable or borderline resectable pancreatic cancer who are enrolled in a multi-site clinical trial (NCT03483038) receiving neoadjuvant NEO-Nali-IRI (oxaliplatin, liposomal irinotecan and 5- FU) followed by surgical resection were asked to provide serial microbiome collections of saliva, urine (collected in clinic), and stool with a dietary log during the following four (or five) time points: at baseline, mid-therapy (after C4), at completion of chemotherapy (after C8), after radiation if applicable, and at 4-6 weeks post-operative. Participants were given stool collection kits during clinic visits for home sample acquisition. All stool samples were mailed to the University of Florida Health Cancer Center Microbiome Biorepository. Demographics, stage, medical history and concurrent medications including antimicrobics and probiotics, chemotherapy dose-reductions, delays, discontinuations, adverse events, safety adverse events, attribution of causality, and hospitalizations were obtained. Outcomes include imaging response using RECIST criteria, CA 19-9 trend, development of metastatic disease, and the ability to proceed to definitive surgical resection. DNA will be extracted from stool and analyzed using 16S rRNA sequencing methods to determine signatures and alpha/beta biodiversity. Descriptive statistics and correlative analysis will be reported. Continuous and categorical variables will be compared with Student’s t-test and Chi-squared test. Multiple groups will be compared by ANOVA. Kaplan-Meier logistic regression will be performed to compare outcomes between the different microbiota groupings. Conclusion: Serial microbiome collection from a multi-site clinical trial is feasible during neoadjuvant chemotherapy for pancreatic cancer and can increase the diversity of the sample population. Citation Format: Sherise Rogers, Ryan Thomas, Ibrahim Nassour, Ilyas Sahin, Brian Ramnaraign, Karen Russell, Steven Hughes, Kathryn Hitchcock, Omar Kayaleh, Anita Turk, Maisey Ratcliff, Thomas George. Feasibility of serial microbiome collection in a multi-site neoadjuvant pancreatic cancer clinical trial allowing for a diverse patient population [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1010.

Adjuvant Gemcitabine Versus Neoadjuvant/Adjuvant FOLFIRINOX in Resectable Pancreatic Cancer: The Randomized Multicenter Phase II NEPAFOX Trial.

Although addition of adjuvant chemotherapy is the current standard, the prognosis of pancreatic cancers still remains poor. The NEPAFOX trial evaluated perioperative treatment with FOLFIRINOX in resectable pancreatic cancer. This multicenter phase II trial randomized patients with resectable or borderline resectable pancreatic cancer without metastases into arm (A,) upfront surgery plus adjuvant gemcitabine, or arm (B,) perioperative FOLFIRINOX. The primary endpoint was overall survival (OS). Owing to poor accrual, recruitment was prematurely stopped after randomization of 40 of the planned 126 patients (A: 21, B: 19). Overall, approximately three-quarters were classified as primarily resectable (A: 16, B: 15), and the remaining patients were classified as borderline resectable (A: 5, B: 4). Of the 12 evaluable patients, 3 achieved partial response under neoadjuvant FOLFIRINOX. Of the 21 patients in arm A and 19 patients in arm B, 17 and 7 underwent curative surgery, and R0-resection was achieved in 77% and 71%, respectively. Perioperative morbidity occurred in 72% in arm A and 46% in arm B, whereas non-surgical toxicity was comparable in both arms. Median RFS/PFS was almost doubled in arm B (14.1months) compared with arm A (8.4months) in the population with surgical resection, whereas median OS was comparable between both arms. Although the analysis was only descriptive owing to small patient numbers, no safety issues regarding surgical complications were observed in the perioperative FOLFIRINOX arm. Thus, considering the small number of patients, perioperative treatment approach appears feasible and potentially effective in well-selected cohorts of patients. In pancreatic cancer, patient selection before initiation of neoadjuvant therapy appears to be critical.

Comparison of neoadjuvant treatment and surgery first for resectable or borderline resectable pancreatic carcinoma: A systematic review and network meta-analysis of randomized controlled trials.

Current treatment recommendations for resectable or borderline pancreatic carcinoma support upfront surgery and adjuvant therapy. However, neoadjuvant therapy (NT) seems to increase prognosis of pancreatic carcinoma and come to everyone's attention gradually. Randomized controlled trials offering comparison with the NT are lacking and optimal neoadjuvant treatment regimen still remains uncertain. This study aims to compare both treatment strategies for resectable or borderline resectable pancreatic cancer. The PRISMA checklist was used as a guide to systematically review relevant peer-reviewed literature reporting primary data analysis. We searched PubMed, Medline, EMBASE, Cochrane Datebase and related reviews for randomized controlled trials comparing neoadjuvant therapy with surgery first for resectable or borderline resectable pancreatic carcinoma. We estimated relative hazard ratios (HRs) for median overall survival and ratios risks (RRs) for microscopically complete (R0) resection among different neoadjuvant regimens and major complications. We assessed the effects of neoadjuvant therapy on R0 resection rate and median overall survival with Bayesian analysis. Thirteen eligible articles were included. Eight studies performed comparison neoadjuvant therapy with surgery first, and R0 resection rate was recorded in seven studies. Compared with surgery first, neoadjuvant therapy did increase the R0 resection rate (RR = 1.53, I2 = 0%, P< 0.00001), there was a certain possibility that gemcitabine + cisplatin (Gem+Cis) + Radiotherapy was the most favorable in terms of the fact that there was no significant difference concerning the results from the individual studies. In direct comparison, four studies were included and estimated that Neoadjuvant therapy improved mOS compared with upfront surgery (HR 0.68, 95% CI 0.58-0.92; P = 0.012; I2 = 15%), after Bayesian analysis it seemed that regimen with Cisplatin/ Epirubicin then Gemcitabine/ Capecitabine (PEXG) was most likely the best with a relatively small sample size. The rate of major surgical complications was available for six studies and ranged from 11% to 56% with neoadjuvant therapy and 11% to 45% with surgery first. There was no significant difference between neoadjuvant therapy and surgery first, also with a high heterogeneity (RR = 0.96, 95%CI = 0.65-1.43; P = 0.85; I2 = 46%). In conclusion neoadjuvant therapy might offer benefit over up-front surgery. Neoadjuvant therapy increased the R0 resection rate with gemcitabine + cisplatin + Radiotherapy that was the most favorable and improved mOS with Cisplatin/ Epirubicin then Gemcitabine/ Capecitabine (PEXG) that was most likely the best.

Multicenter Prospective Cohort Study of Neoadjuvant Chemotherapy for Borderline Resectable Pancreatic Cancer (YPB-001).

The present multicenter prospective observational study investigated the effectiveness and safety of neoadjuvant chemotherapy (NAC) for patients with borderline resectable pancreatic cancer (BRPC) and those with RPC contacting major vessels, with respect to a historical control of upfront surgery. Patients with BRPC and RPC contacting major vessels were prospectively registered and administered NAC with durations and regimens determined by the corresponding treating physician. Our primary aim was to assess the R0 resection rate, and secondary aim was to evaluate safety, resection rate, time to treatment failure, overall survival, and response rate. Fifty of 52 enrolled patients were analyzed; 2 with serious comorbidities died during treatment. Thirty-one patients underwent resection, with R0 resection being achieved in 26 (52% of total and 84% of all resected cases). Univariate and multivariate analyses indicated age (≥75 years) as the only independent predictor of nonresection. Median progression-free survival and median survival time were longer in the prospective cohort than in the historical cohort. Overall, NAC for BRPC in real-world setting might yield R0 resection rates similar to those reported in previous clinical studies. Development of safe regimens and management strategies that can maintain treatment intensity in geriatric patients is warranted.

Reconsideration of the clinical impact of neoadjuvant therapy in resectable and borderline resectable pancreatic cancer: A dual-institution collaborative clinical study

PurposeWe investigated true indication of neoadjuvant therapy (NAT) in resectable pancreatic cancer and the optimal surgical timing in borderline resectable pancreatic cancer. MethodsA total of 687 patients with resectable or borderline resectable pancreatic cancer were enrolled. Survival analysis was performed by intention-to-treat analysis and propensity score matching (PSM) was conducted. ResultsIn resectable disease, the NAT group showed better overall survival (OS) compared with the upfront group. Multivariate analysis identified CA19-9 level (≥100 U/mL) and lymph node metastasis to be prognostic factors, and a tumor size of 25 mm was the optimal cut-off value to predict lymph node metastasis. There was no significant survival difference between patients with a tumor size ≤25 mm and CA19-9 < 100 U/mL and those in the NAT group. In borderline resectable disease, OS in the NAT group was significantly better than that in the upfront group. CEA (≥5 ng/mL) and CA19-9 (≥100 U/mL) were identified as prognostic factors; however, the OS of patients fulfilling these factors was worse than that of the NAT group. ConclusionsNAT could be unnecessary in patients with tumor size ≤25 mm and CA19-9 < 100 U/mL in resectable disease. In borderline resectable disease, surgery should be delayed until tumor marker levels are well controlled.

Safety of biliary drainage with 6-mm metallic stent for preoperative obstructive jaundice in pancreatic cancer: PURPLE SIX STUDY.

The 10-mm self-expandable metal stent (SEMS) is the standard for endoscopic transpapillary biliary drainage before pancreatic cancer surgery. However, the efficacy of stents thinner than 10mm has not been adequately validated. Therefore, we aimed to evaluate the safety of a 6-mm fully covered SEMS (FCSEMS) for distal malignant biliary obstruction (DMBO) during preoperative chemotherapy for pancreatic cancer. This was a single-arm, multicenter, prospective phase II study of endoscopic transpapillary initial biliary drainage for DMBO before pancreatic cancer surgery. The primary endpoint was stent-related adverse events, and the key secondary endpoint was the non-recurrent biliary obstruction (non-RBO) rate during the observation period for both resectable (R) and borderline resectable (BR) pancreatic cancers. The study enrolled 33 patients, among whom 32 received the study treatment. There were 23 and 9 cases of R and BR pancreatic cancers, respectively. The technical and clinical success rates were 97.0% and 90.1%, respectively. The stent-related adverse event rate was 3.1% (n=1, acute pancreatitis) (95% confidential interval, 0.00-16.2), which met the criteria to be considered safe. The overall non-RBO rate during the observation period (median 96days) was 78.1% (82.6% and 66.7% for R and BR pancreatic cancer cases, respectively). The 6-mm FCSEMS is an extremely safe metallic stent with a low stent-related adverse event rate of 3.1% for preoperative biliary drainage in pancreatic cancer. It is considered the optimal stent for preoperative biliary drainage in terms of the non-RBO rate. UMIN Clinical Trial Registry (UMIN-CTR 000041704).

Dose-escalated SBRT for borderline and locally advanced pancreatic cancer. Feasibility, safety and preliminary clinical results of a multicenter study

BackgroundPancreatic Stereotactic Body Radiotherapy (SBRT) allows for the administration of a higher biologically effective doses (BED), that would be essential to achieve durable tumor control. Escalating treatment doses need a very accurate tumor positioning and motion control during radiotherapy.The aim of this study to assess the feasibility and safety of a Simultaneous Integrated Boost (SIB) dose-escalated protocol at 45 Gy, 50 Gy and 55 Gy in 5 consecutive daily fractions, in Border Line Resectable Pancreatic Cancer (BRCP) /Locally Advanced Pancreatic Cancer (LAPC) by means of a standard LINAC platform. MethodsPatients diagnosed of BRPC/LAPC, candidates for neoadjuvant chemotherapy and SBRT, in four university hospitals of the province of Las Palmas (Canary Islands, Spain) were included in this prospective study. Radiotherapy was administered using standard technology (LINACS) with advanced positioning (Lipiodol® and metallic stent used as fiducial markers) and tumor motion control (4D, DBH, Calypso®). There were 3 planned dose-escalated SIB groups, 45 Gy/5f (9 patients) 50 Gy/5f (9 + 9 patients) and 55 Gy/5f (9 patients). The defined primary end points of the study were the safety and feasibility of the proposed treatment protocol. Secondary endpoints included radiological tumor response after SBRT, local control and survival. ResultsFrom June 2017 to December 2022, sixty-two patients were initially assessed for eligibility in the study in the four participating centers, and 49 were candidates for chemotherapy (CHT). Forty-one were referred to radiotherapy after CHT and 33 finally were treated by escalated-dose SIB, 45 Gy (9 patients) 50 Gy (16 patients), 55 Gy(8 patients). All patients completed the scheduled treatment and no acute or late severe (≥grade3) gastrointestinal toxicity was observed.Local response was analyzed by CT/MRI two months after the end of SBRT. Ten patients (31,25 %) achieved objective response (2/9:45 Gy, 5/15:50 Gy, 3/8:55 Gy). Follow-up was closed as July 2023. Freedom from local progression at 1-2y were 89,3% (95 %CI:83,4–95,2%) and 66 % (95 %CI:54,6–77,4%) respectively. The 1-2y survival rates were 95,7% (95 %CI:91,4–100 % and 48,6% (95 %CI:37,7–59,5%) respectively. ConclusionThese promising results should be confirmed by further studies with larger sample size and extended follow-up period.

Short- and Long-Term Outcomes of Neoadjuvant Chemoradiotherapy Followed by Pancreatoduodenectomy in Elderly Patients with Resectable and Borderline Resectable Pancreatic Cancer: A Retrospective Study.

Background: The efficacy of neoadjuvant chemoradiotherapy (NACRT) followed by pancreatoduodenectomy (PD) in elderly patients with pancreatic ductal adenocarcinoma (PDAC) remains unclear. Methods: This retrospective analysis of prospectively collected data examined the effect of NACRT followed by PD in elderly patients with PDAC. A total of 112 patients with resectable (R-) and borderline resectable (BR-) PDAC, who were planned for PD and received NACRT between 2009 and 2022, were assessed. Changes induced by NACRT, surgical outcomes, nutritional status, renal and endocrine functions, and prognosis were compared between elderly (≥75 years, n = 43) and non-elderly (<75 years, n = 69) patients over two years following PD. Results: Completion and adverse event rates during NACRT, nutritional status, renal function, endocrine function over two years postoperatively, and prognosis did not significantly differ between the two groups. Low prognostic index after NACRT and the absence of postoperative adjuvant chemotherapy may be adverse prognostic indicators for elderly patients undergoing NACRT for R- and BR-PDAC. Conclusions: Despite a higher incidence of postoperative complications, NACRT followed by PD can be safely performed in elderly patients, resulting in a prognosis similar to that in non-elderly patients.

Prognostic Significance of Biologic Factors in Patients with a Modest Radiologic Response to Neoadjuvant Treatment for Resectable and Borderline Resectable Pancreatic Cancers: Impact of the Combination Index of Sialyl-Lewis Antigen-Related Tumor Markers.

Appropriate re-evaluation after neoadjuvant treatment (NAT) is important for optimal treatment selection. Nonetheless, determining the operative eligibility of patients with a modest radiologic response remains controversial. This study aimed to assess the prognostic significance of biologic factors for patients showing a modest radiologic response to NAT and investigate the tumor markers (TMs), CA19-9 alone, DUPAN-II alone, and their combination, to create an index that combines these sialyl-Lewis antigen-related TMs associated with treatment outcomes. This study enrolled patients deemed to have a "stable disease" by RECIST classification with slight progression (tumor size increase rate, ≤20%) as their radiologic response after NAT. A sialyl-Lewis-related index (sLe index), calculated by adding one fourth of the serum DUPAN-II value to the CA19-9 value, was created. The prognostic significances of CA19-9, DUPAN-II, and the sLe index were assessed in relation to postoperative outcomes. An sLe index lower than the cutoff value (45.25) was significantly associated with favorable disease-free survival. Moreover, the post-NAT sLe index had a higher area under the curve value for recurrence within 24 months than the post-NAT levels of CA19-9 or DUPAN-II alone. Multivariable analysis showed that a post-NAT sLe index higher than 45.25 was the single independent predictive factor for recurrence within 24 months. Additional evaluation of biologic factors can potentially enhance patient selection, particularly for patients showing a limited radiologic response to NAT. The authors' index is a simple indicator for the biologic evaluation of multiple combined sialyl-Lewis antigen-related TMs and may offer a better predictive significance.

Survival benefit of neoadjuvant FOLFIRINOX for patients with borderline resectable pancreatic cancer.

While patients with borderline resectable pancreatic cancer (BRPC) are a target population for neoadjuvant chemotherapy (NAC), formal guidelines for neoadjuvant therapy are lacking. We assessed the perioperative and oncological outcomes in patients with BRPC undergoing NAC with FOLFIRINOX for patients undergoing upfront surgery (US). The AHPBA criteria for borderline resectability and/or a CA19-9 level > 100 μ/mL defined borderline resectable tumors retrieved from a prospectively populated institutional registry from 2007 to 2020. The primary outcome was overall survival (OS) at 1 and 3 years. A Cox Proportional Hazard model based on intention to treat was used. A receiver-operator characteristics (ROC) curve was constructed to assess the discriminatory capability of the use of CA19-9 > 100 μ/mL to predict resectability and mortality. Forty BRPC patients underwent NAC, while 46 underwent US. The median OS with NAC was 19.8 months (interquartile range [IQR] 10.3-44.24) vs. 10.6 months (IQR 6.37-17.6) with US. At 1 year, 70% of the NAC group and 41.3% of the US group survived (p = 0.008). At 3 years, 42.5 % of the NAC group and 10.9% of the US group survived (p = 0.001). NAC significantly reduced the hazard of death (adjusted hazard ratio, 0.20; 95% confidence interval, 0.07-0.54; p = 0.001). CA19-9 > 100 μ/mL showed poor discrimination in predicting mortality, but was a moderate predictor of resectability. We found a survival benefit of NAC with FOLFIRINOX for BRPC. Greater pre-treatment of CA19-9 and multivessel involvement on initial imaging were associated with progression of the disease following NAC.

FOLFIRINOX plus high intensity focused ultrasound for locally advanced/borderline resectable pancreatic ductal adenocarcinoma: A prospective single arm phase II trial.

670 Background: FOLFIRINOX has been the standard regimen for locally advanced pancreatic cancer (LAPC) for palliation and borderline resectable pancreatic cancer (BRPC) for neoadjuvant treatment. According to the results of animal studies, concurrent use of high intensity focused ultrasound (HIFU) and chemotherapy can enhance the drug delivery to the target tissue. In this phase II trial, we aimed to evaluate the safety and therapeutic efficacy of FOLFIRINOX plus HIFU for patients with LAPC or BRPC. Methods: This study was designed as a prospective single center phase II trial (Study identifier: NCT05262452). We prospectively enrolled 60 patients (M:F=35:25; median age, 67.0 years old) with LAPC (n=23) or BRPC (n=37). The median tumor size was 4.0 cm (Interquartile range, 2.7-4.6). All patients were treated by FOLFIRINOX (oxaliplatin, 85mg/m2 of body-surface area; irinotecan, 180mg/m2; leucovorin, 400 mg/m2; and fluorouracil, 400 mg/m2 given as a bolus followed by 2400 mg/m2 given as a 46-hour continuous infusion) every 2 weeks until disease progression. HIFU was combined in the first 4 cycles of chemotherapy with following parameters: intensity of 2.0 kw/cm2, duty cycle of 1%, exposure time of 3 seconds and PRF of 10Hz. Follow-up contrast enhanced CT was taken every 4 cycles for the response evaluation using response evaluation criteria for solid tumor 1.1. Overall survival (OS) and progression-free survival were estimated using Kaplan-Meier method. All analyses were intention-to-treat. Results: Two patients withdrew the consent, and two patients could not complete planned 4 cycles of FOLFIRINOX plus HIFU treatment owing to sepsis from severe neutropenia related to chemotherapy. Among 56 patients who completed the 4 cycle of FOLFIRINOX plus HIFU and continued chemotherapy, partial response was achieved in 36 patients (60.0%, 36/60), and stable disease in 20 patients. Regarding the adverse effect (AE), 32 of 60 patients experienced grade 3 (n=22) or grade 4 (n=10) AE, all of them were related to FOLFIRINOX chemotherapy. No AE related to HIFU was observed. The estimated OS was 94.8%, 75.9% and 67.6% at 6-, 12- and 18 months, respectively. Regarding the PFS, the 6-, 12- and 18-month PFS was 91.9%, 70.3% and 56.2%, respectively. Conclusions: FOLFIRINOX plus HIFU was safe and effective treatment for LAPC/BRPC, providing 60.0% of partial response rate without any additional AE to chemotherapy. Clinical trial information: NCT05262452 .

Postoperative complications following neoadjuvant therapy and surgery in a phase 2 borderline resectable pancreatic cancer clinical trial (Alliance A021501).

664 Background: Postoperative complications in patients with borderline resectable pancreatic cancer treated with neoadjuvant therapy and pancreatectomy in the national cooperative group setting have not been previously characterized. Further, the impact of preoperative hypofractionated radiotherapy on postoperative outcomes is largely unknown. We sought to quantify perioperative morbidity among patients with pancreatic cancer who received neoadjuvant modified FOLFIRINOX chemotherapy with or without hypofractionated radiotherapy on a multicenter clinical trial. Methods: The A021501 phase 2 trial randomized patients with borderline resectable pancreatic ductal adenocarcinoma to 8 doses of mFOLFIRINOX (Arm 1) or 7 doses of mFOLFIRINOX then hypofractionated radiotherapy (Arm 2), followed by pancreatectomy (Dec 31, 2016-Jan 1, 2019). Patients underwent resection according to defined operative standards at enrolling centers without specific requirements for either surgeon or hospital volume. Surgical complications and adverse events were assessed and captured at a single time point of 90 days after surgery and compared between treatment arms. Results: Of 126 enrolled patients, 51 (40%) underwent pancreatectomy (n=32, Arm 1; n=19, Arm 2) at 28 institutions. Vascular resection was performed in 19 patients (37%). One patient in Arm 2 died within 90 days after surgery. Rates of any surgical complication were 19% (n=6) in Arm 1 and 42% (n=8) in Arm 2 (p=0.07). Median length of stay was 7 days (range 5-38 days). Five (10%) patients required reoperation within 90 days. Readmission rates were higher in Arm 2 than Arm 1 (16% vs. 42%, p=0.04) but there were no differences in rates of reoperation, pancreatic fistula or abscess requiring drainage, or wound infection between study arms. 54% of patients (n=26/48) experienced a grade 3 or higher adverse event, with no difference between treatment arms (47% versus 67%, p=0.7). Rates of initiation of adjuvant therapy did not differ between treatment arms (66% vs. 68%, p=0.4). Pancreatic fistula and abscess were associated with adjuvant therapy (p&lt;0.01). No difference in overall survival was observed based on occurrence of surgical complications (HR 1.1; 95% CI 0.5-2.6). Conclusions: In this national cooperative group study of patients with borderline resectable pancreatic cancer,postoperative complications following neoadjuvant chemotherapy, radiation, and surgical resection were consistent with rates previously reported by high-volume institutions and using large datasets. Multimodality trials of preoperative therapy for locoregionally advanced pancreatic cancer may be safely performed in the cooperative group setting. Clinical trial information: NCT02839343 .

Development and validation of a nomogram model based on pretreatment ultrasound and contrast-enhanced ultrasound to predict the efficacy of neoadjuvant chemotherapy in patients with borderline resectable or locally advanced pancreatic cancer

ObjectivesTo develop a nomogram using pretreatment ultrasound (US) and contrast-enhanced ultrasound (CEUS) to predict the clinical response of neoadjuvant chemotherapy (NAC) in patients with borderline resectable pancreatic cancer (BRPC) or locally advanced pancreatic cancer (LAPC).MethodsA total of 111 patients with pancreatic ductal adenocarcinoma (PDAC) treated with NAC between October 2017 and February 2022 were retrospectively enrolled. The patients were randomly divided (7:3) into training and validation cohorts. The pretreatment US and CEUS features were reviewed. Univariate and multivariate logistic regression analyses were used to determine the independent predictors of clinical response in the training cohort. Then a prediction nomogram model based on the independent predictors was constructed. The area under the curve (AUC), calibration plot, C-index and decision curve analysis (DCA) were used to assess the nomogram’s performance, calibration, discrimination and clinical benefit.ResultsThe multivariate logistic regression analysis showed that the taller-than-wide shape in the longitudinal plane (odds ratio [OR]:0.20, p = 0.01), time from injection of contrast agent to peak enhancement (OR:3.64; p = 0.05) and Peaktumor/ Peaknormal (OR:1.51; p = 0.03) were independent predictors of clinical response to NAC. The predictive nomogram developed based on the above imaging features showed AUCs were 0.852 and 0.854 in the primary and validation cohorts, respectively. Good calibration was achieved in the training datasets, with C-index of 0.852. DCA verified the clinical usefulness of the nomogram.ConclusionsThe nomogram based on pretreatment US and CEUS can effectively predict the clinical response of NAC in patients with BRPC and LAPC; it may help guide personalized treatment.

PRIMUS-002: A multicentre, open-label, phase II study examining FOLFOX and nab-paclitaxel (FA) and nab-paclitaxel and gemcitabine (AG) as neoadjuvant therapy for (borderline) resectable pancreatic cancer (PC), focusing on biomarker and liquid biopsy development.

669 Background: There is increasing evidence suggesting benefit from a neoadjuvant approach to PC. However, the optimal regimen is unclear and will likely require a precision medicine approach. Platinum-containing regimens have shown survival benefit for PC, with occasional exceptional responders, but biomarkers (BM) of response are not well defined and treatment decisions are often based on patient performance status (PS) and co-morbidity. Tumors may show defective DNA damage response (DDR), conferring potential selective sensitivity to DNA-damaging agents (e.g. platinum) and newer targeted agents. We have shown that DDR deficiency (DDRd) is present in up to 20% of PC. This study aimed to exploit DDRd as a therapeutic vulnerability, with integrated analysis to define candidate BM for FA and AG response. Methods: Patients with resectable and borderline resectable PDAC patients who were deemed fit for potential surgery were recruited into the trial between April 2019 and July 2021. All had been molecularly profiled using the Precision-Panc Clinical Cancer Genome including a novel DDRd assay, and the transcriptome with longitudinal sampling (pre-, during, and post-treatment). Patients received either FA (nab-paclitaxel 150mg/m2 IV, oxaliplatin 85mg/m2, folinic acid 350mg flat dose, fluorouracil infusion 2400mg/m2 continuous IV infusion), or AG (nab-paclitaxel 125mg/m2, gemcitabine 1000 mg/m2) for 3 months, based on patient age and PS. The primary endpoint was disease progression (DP) during neoadjuvant therapy. Results: 31 patients in total were recruited into the trial unfortunately the trial was terminated early due to funding issues. The median age was 62 years old (31-73) 21 patients were male and 10 female. 7 resectable cases and 24 borderline resectable at diagnosis were included in the study. 26 patients were recruited to the FOLFOX-A arm and 5 to the AG arm. Following chemotherapy 6 patients had partial response, 17 stable disease and 6 progressive disease. 23 patients proceeded to surgery of which 6 the radical surgery was abandoned due to extent of malignancy The overall median survival time was 20.6 months with a 90% confidence interval of (12.9 months to 24.9 months). The median survival time was 23.7 months with 90% confidence interval of (12.9 months to 24.9 months) for FOLXFOX-A, and 20.5 months with a 90% confidence interval of (8.9 months to NA) for the AG arm Conclusions: We have demonstrated that these 2 regimes can be utilised in the neoadjuvant setting with surgery being undertaken safely following therapy (there was no surgical mortality and morbidity is in line of other international series). Further work is ongoing to identify potential biomarkers which may lead to better patient selection for a neoadjuvant approach. Clinical trial information: ISRCTN34129115 .

Impact of facility volume on outcomes in patients with pancreatic cancer treated with radiotherapy.

644 Background: The impact of facility volume on overall survival (OS) outcomes in patients with pancreatic cancer (PC) treated with radiotherapy (RT), both standard chemoradiation (CRT) and stereotactic body radiation therapy (SBRT) is not well-defined. Methods: This retrospective study analyzed 16,315 patients with locally advanced (LA) or borderline resectable (BR) PC from the National Cancer Database (2004-2019) who received neoadjuvant RT or RT without surgery across RT facilities with low- (&lt;10 cases/yr), intermediate- (10-20 cases/yr), and high-volumes (&gt;20 cases/yr) of PC cases. Log rank and cox regression were used for univariable and multivariable survival analysis, and Kaplan-Meier curves were generated. Results: Patients were largely treated at low (n=8055) volume centers, followed by intermediate (n=3783), and high (n=4477). Approximately half of the cohort were male (51.4%), and predominantly white (82.5%), and non-Hispanic (92%). On univariable analysis (Table), high-volume centers had improved survival outcomes in the overall population, as well as in both SBRT and CRT subsets (p&lt;0.0001). On multivariable analysis, treatment during the most recent time period: 2016-2019 (HR 0.646, p&lt;0.001), receiving care at a high-volume center (HR 0.844, p&lt;0.001), use of SBRT (HR 0.915, p&lt;0.001), administration of multiagent chemotherapy (HR 0.706, p&lt;0.001) and undergone surgical resection (HR 0.405, p&lt;0.001) were associated with improved OS. In a subgroup analysis of patients receiving SBRT, median OS was 22.6 months for high-volume, 20.0 for intermediate-volume and 18.4 months at low-volume centers (p&lt;0.001). Conclusions: Patients receiving RT for LAPC or BRPC at high-volume centers had longer OS compared to those receiving radiation at intermediate- or low-volume centers. In those undergoing SBRT, treatment at high-volume centers had improved OS compared to intermediate- and low-volume centers. These findings suggest that radiation oncologists’ expertise is critical for providing high-quality RT in PC, especially for SBRT.[Table: see text]