Meta-analysis comparing upfront surgery with neoadjuvant treatment in patients with resectable or borderline resectable pancreatic cancer

Relationship of Time to First Therapy and Survival Outcomes of Neoadjuvant Chemotherapy Versus Upfront Surgery Approach in Resectable Pancreatic Ductal Adenocarcinoma

INTRODUCTION

Evidence demonstrating overall survival benefit of neoadjuvant chemotherapy (NAC) followed by surgical resection over upfront surgical resection for resectable pancreatic ductal adenocarcinoma (PDAC) has been mixed. The time to first therapy (TTFT) variable has not been studied as a contributing factor.

METHODS

A nationwide retrospective analysis using the National Cancer Database to evaluate patients with clinical stage T1 and T2 PDACs from 2010 to 2020. Cox proportional hazards model was used to evaluate the impact of NAC followed by definitive surgery compared to upfront surgery on overall survival with and without TTFT.

RESULTS

Total of 43,174 patients were included-9874 patients with clinical stage T1 and 33,300 patients with T2 PDACs. There were increasing trends in the NAC approach from 2.9% in 2010 to more than 25% by 2020 and decreasing trends in the upfront surgery approach from 69.34% in 2010 to 31.87% by 2020. There were significant differences in TTFT according to the treatment choice with upfront surgery group having a significantly shorter TTFT-proportion of those receiving first treatment within the first week was 24.32% in the upfront surgery compared to 4.22% in the NAC group. In the adjusted cox regression without the TTFT variable, there was a 25% higher rate of death in the upfront surgery compared to the NAC group (hazard ratio 1.25, 95% confidence interval 1.19-1.30). When the adjusted regression was performed with addition of a TTFT interaction term, there was survival disadvantage of upfront surgery approach in patients whose TTFT occurred after 1 wk, but not in those with TTFT occurring in less than 1 wk (hazard ratio 1.01, 95% confidence interval 0.86-1.17).

CONCLUSIONS

Our study emphasizes the importance of incorporating TTFT variable when comparing NAC versus upfront surgery approach in PDAC. Future studies comparing NAC to upfront surgery in resectable PDAC should consider incorporating the TTFT variable.

Role of volumetric tumor enhancement on CT in predicting overall survival in patients with unresectable pancreatic ductal adenocarcinoma

PURPOSE

To assess the utility of volumetric tumor enhancement on CT to predict tumor treatment response and the overall survival (OS) of patients with PDAC undergoing FOLFIRINOX-based systemic chemotherapy. Additionally, we aim to explore the performance of a novel model that incorporates relevant volumetric CT-derived parameters to the established RECIST 1.1 in predicting both treatment response and OS.

MATERIAL AND METHODS

In this retrospective single-institution study, 127 patients with PDAC who received FOLFIRINOX neoadjuvant chemotherapy between December 2012 and November 2021 were included. Manual volumetric segmentation of the single largest tumor was performed on portal venous phase images. Total and enhancing tumor volumes were calculated. Response by RECIST 1.1 was compared to response by tumor volume and enhancing tumor volume on follow-up CT.

RESULTS

There was no association between overall survival and RECIST 1.1 (p-value = 0.284), volumetric RECIST (p-value = 0.402), and other volumetric CT variables, except for a percentage reduction in enhancing tumor volume (p-value = 0.043). Using univariate survival analysis for categorical thresholds defined by CART, the percentage change in enhancing tumor volume was associated with OS (p-value = 0.018). There was also a significant association between baseline enhancing tumor volume and OS (p-value <0.0001). Using these two categories, we defined a multivariable model associated with OS (p-value <0.0001).

CONCLUSION

Percentage reduction in enhancing tumor volume was related to OS in non-surgical PDAC patients treated with FOLFIRINOX chemotherapy and could potentially be incorporated into patient survival prediction models.

Assessment of Outcomes by Intention-to-Treat Comparison for Locally Advanced Pancreatic Cancer: A Population-Derived Cohort Study

BACKGROUND

The overall treatment response among patients with locally advanced pancreatic cancer (LAPC) is poorly understood as most studies report solely on resected patients. We aimed to investigate the outcomes in patients with LAPC as an intention-to-treat-analysis from the time of diagnosis from a complete source population.

PATIENTS AND METHODS

An observational cohort study in a population-defined region within a universal healthcare system. All consecutive patients discussed at multi-disciplinary tumour board (MDT), aged ≥ 18 years and diagnosed with LAPC were included. Exposure was set as recommended treatment by MDT (i.e. upfront surgery, neoadjuvant therapy, palliative treatment or best supportive care). Outcome measures were overall survival analysed by Kaplan-Meier survival estimates and multivariable analyses using logistic regression for odds ratios (OR) and Cox proportional hazard analysis for hazard ratios (HR).

RESULTS

In total, 8803 MDT events (6055 unique patients) with pancreatic disease were held during the study period. Some 1436 (24%) had pancreatic cancer, of which 162 (11%) had LAPC and 134 met the population-defined criteria. In overall survival analyses, the patients who were recommended neoadjuvant therapy (± surgery) demonstrated no significant difference to palliative chemotherapy (median 11.0 months vs. 11.8 months; p = 0.226). In multivariable analysis, adjusted OR for overall survival comparing the treatment groups was 0.27 (95% CI 0.02-3.29, p = 0.306) and Cox proportional HR 0.96 (95% CI 0.58-1.59, p = 0.865).

CONCLUSIONS

In patients with LAPC, survival was not statistically different between those recommended for attempt at neoadjuvant (± surgery) compared with those recommended palliative chemotherapy. The findings suggest that conversion/downstaging chemotherapy is successful in only a select few.

Neoadjuvant gemcitabine and S-1 in pancreatic ductal adenocarcinoma: Effects on nutritional status and pancreaticoduodenectomy outcomes

BACKGROUND

With the advent of improved chemotherapy options, neoadjuvant chemotherapy has gained acceptance as a multidisciplinary treatment approach for localized pancreatic ductal adenocarcinoma. This study aimed to clarify whether neoadjuvant chemotherapy with gemcitabine and S-1 influences preoperative nutritional status and postoperative outcomes, particularly in patients undergoing highly invasive pancreatic resection.

METHODS

Patients with resectable pancreatic ductal adenocarcinoma who underwent pancreaticoduodenectomy as upfront surgery or after neoadjuvant chemotherapy with gemcitabine and S-1 between January 2015 and December 2022 were assessed. In addition to perioperative surgical outcomes, preoperative nutritional status was evaluated using serum albumin, controlling nutritional status, and prognostic nutritional index.

RESULTS

A total of 158 patients who underwent upfront pancreaticoduodenectomy and 119 who received neoadjuvant chemotherapy with gemcitabine and S-1 before pancreaticoduodenectomy were evaluated. Preoperative nutritional assessments (serum albumin, controlling nutritional status score, and prognostic nutritional index) showed no significant differences between groups, either at the initial consultation or immediately before surgery. No significant differences were observed in postoperative outcomes, including blood loss, operation time, and morbidity. The neoadjuvant chemotherapy with gemcitabine and S-1 group had a significantly greater rate of negative tumor margins (R0 resection rate 86% vs 74%, P = .018), and improved overall survival (hazard ratio, 0.41; 95% confidence interval, 0.25-0.67, P < .001) compared with the upfront pancreaticoduodenectomy group.

CONCLUSIONS

Neoadjuvant chemotherapy with gemcitabine and S-1 does not adversely impact preoperative nutritional status and enhances the effectiveness of pancreaticoduodenectomy for resectable pancreatic ductal adenocarcinoma, leading to improved pathologically curative resection rates and overall survival.

Impact of Metastatic Pattern on Survival Following Pancreatectomy for Cancer

BACKGROUND AND METHODS

The incidence of pancreatic cancer is increasing, and up to 55% of patients present with metastatic disease at the time of diagnosis. Many patients also develop metastatic disease following surgical resection. The impact of metastatic patterns on outcomes has not been described. A retrospective chart review was conducted of patients with pancreatic adenocarcinoma treated at a tertiary care center from 2012 to 2023. Patients who presented with metastatic disease or developed metastatic disease during their treatment course were identified. Univariate analysis was performed to identify factors associated with specific metastatic patterns. Kaplan-Meier survival curves were estimated for metastatic sites and stratified by treatment.

RESULTS

Of the 330 patients identified, 192 (58.2%) presented with locoregional disease and underwent curative intent surgery before developing metastases, and 138 (41.8%) presented initially with metastatic disease. Median overall survival (OS) with metastases for all patients was 6 months. For patients who underwent curative intent surgery, OS was significantly worse for those who developed peritoneal metastasis compared to patients who developed other sites of metastases (median OS 5.4 vs. 9.2 months, p = 0.0005).

CONCLUSION

The development of peritoneal metastases after surgery for pancreatic cancer is associated with worse OS compared to other sites of metastatic disease.

Best Practices for Delivering Neoadjuvant Therapy in Pancreatic Ductal Adenocarcinoma

Importance

Neoadjuvant therapy (NT) is an increasingly used treatment strategy for patients with localized pancreatic ductal adenocarcinoma (PDAC). Little research has been conducted on cancer care delivery during NT, and the standards for optimal delivery of NT have not been defined.

Objective

To develop consensus best practices for delivering NT to patients with localized PDAC.

Design, Setting, and Participants

This study used a modified Delphi approach consisting of 2 rounds of voting, and a series of virtual conferences (from October to December 2023) to reach expert consensus on candidate best practice statements generated from a systematic review of the literature and expert opinion. An interdisciplinary panel was formed including 47 North American experts from surgical, medical, and radiation oncology, radiology, pathology, gastroenterology, integrative oncology, anesthesia, pharmacy, nursing, cancer care delivery research, and nutrition as well as patient and caregiver stakeholders.

Main Outcome and Measures

Statements that reached 75% agreement or greater were included in final consensus statements.

Results

Of the 47 participating panel members, 27 (57.64%) were male, and the mean (SD) age was 47.6 (8.2) years. Physicians reported completing training a mean (SD) 14.6 (8.6) years prior and seeing a mean (SD) 110.6 (38.4) patients with PDAC annually; 35 (77.7%) were in academic practice. Final consensus was reached on 82 best practices for delivering NT. Of these, 38 statements focused on pre-NT practices, including diagnosis and staging (n = 15), evaluation and optimization (n = 20), and decision-making (n = 3); 29 statements defined best practices during NT, including initiation (n = 3), delivery of therapy (n = 8), restaging practices (n = 12), and management of complications during NT (n = 6); and 15 best practices were identified to guide treatment post-NT, focusing on surgery (n = 7), pathology (n = 4), and follow-up (n = 3).

Conclusions

Using a modified Delphi consensus technique, best practice guidelines were developed focusing on the optimal standards for delivering NT to patients with localized PDAC. Given the prognostic importance of completing multimodality therapy, efforts to standardize and optimize the delivery of NT represent an immediate opportunity to decrease care variation and improve outcomes for patients with PDAC. Future research should focus on validating and implementing best practice standards into clinical practice.

Safety and feasibility of percutaneous abdominal lavage cytology screening (PACS) prior to surgical resection for pancreatic cancer

PURPOSE

This study aimed to evaluate the feasibility, safety, diagnostic yield, and technical aspects of percutaneous abdominal lavage cytology screening (PACS) in patients with resectable pancreatic cancer.

METHODS

This single-center, retrospective study included patients with resectable pancreatic cancer who underwent PACS before pancreatectomy between May 2022 and October 2023. The technical success rate, position of the drainage tube, volume of fluid administered, volume of fluid retrieved, fluid retrieval rate, and adverse events were evaluated. The cytological results of PACS were compared with those of surgical peritoneal lavage performed during pancreatectomy.

RESULTS

Forty-four patients were enrolled in this study. The technical success rate for PACS was 100%. Drainage tube placement was outside the pouch of Douglas in all patients in the right-sided abdominal approach group (n = 10), whereas the placement was in the pouch of Douglas in all patients in the suprapubic approach group (n = 34). The mean volume of fluid administered, mean volume of fluid retrieved, and fluid retrieval rate were 185.0 ± 22.9 ml vs. 97.1 ± 32.0 ml (p < 0.001), 36.8 ± 25.6 ml vs. 50.5 ± 21.6 ml (p = 0.059), and 19.0 ± 12.4% vs. 54.9 ± 21.9% (p < 0.001) in the right abdominal approach and suprapubic approach groups, respectively. No adverse events were reported. The cytological results were benign in 42 patients; no discrepancy was observed in the results of surgical peritoneal lavage (n = 36).

CONCLUSION

PACS is a feasible and safe procedure that can be performed before pancreatectomy in patients with resectable pancreatic cancer. the suprapubic approach may be ideal and PACS could be a screening method to detect carcinomatous peritonitis.

Gaining a new angle on pancreas cancer: A pre-operative thrombelastographic parameter predicts recurrence and survival among patients with resected periampullary and pancreatic adenocarcinoma

BACKGROUND

It has previously been demonstrated that Thrombelastography(TEG) angle may be associated with recurrence and survival in pancreas cancer in a cohort of patients operated on at the University of Colorado in 2016-2017. Now approaching 10 years of follow-up, we revisit these associations and strengthen these claims with multivariate analysis.

METHODS

Retrospective chart review was performed. Statistical analysis was conducted using STATA. Receiver operating characteristic(ROC) curves identified the performance of angle for predicting recurrence&survival. Unadjusted and adjusted cox regression models were used to identify significant predictors of these outcomes.

RESULTS

47 patients were included with median follow-up of 29.6 months. ROC curves for angle predicting recurrence and survival identified a cutoff of 44.5°. KM curves demonstrated that patients above the cutoff were more likely to recur(90%vs46 ​%,p ​= ​0.001) and less likely to survive(16%vs56 ​%,p ​= ​0.001). Angle remained significant on multivariate analyses (HR recurrence:3.64[1.32-10.25],HR survival:3.80[1.38-10.46]).

CONCLUSIONS

TEG angle is independently associated with disease recurrence and overall survival in pancreas cancer. This may be identifying virulent tumor biology, but further studies are required. A prospective study is underway.

A case of needle tract seeding of pancreatic adenosquamous carcinoma after a single endoscopic ultrasound-guided tissue acquisition

Needle tract seeding (NTS) is a rare complication of endoscopic ultrasound-guided tissue acquisition (EUS-TA). Herein, we report the case of an 83 year-old man who presented with a solid mass in the pancreatic tail, measuring 35 mm in diameter, with cystic degeneration. EUS-TA was performed using a 22-gauge biopsy needle, with a single puncture via the stomach; however, no definitive pathological diagnosis was achieved. Due to the strong suspicion of malignancy, surgery was performed at the patient's request, and the postoperative pathological diagnosis was pancreatic adenosquamous carcinoma. One year after surgery, computed tomography revealed a string of bead-like nodules within the gastric wall. Esophagogastroduodenoscopy revealed three submucosal, tumor-like raised lesions aligned in a row on the upper posterior wall of the gastric body. EUS detected a solid mass with cystic degeneration. Histological findings from EUS-TA specimens were consistent with those from the pancreatic resection specimen, leading to a diagnosis of NTS. Although reports of NTS have been increasing in recent years, cases of NTS occurring after only a single puncture remain extremely rare. This case clearly demonstrates that NTS can occur even after a single puncture, highlighting the importance of obtaining thorough informed consent regarding this risk prior to performing EUS-TA.

Value of radiomics features extracted from baseline computed tomography images in predicting overall survival in patients with nonsurgical pancreatic ductal adenocarcinoma: incorporation of a radiomics score to a multiparametric nomogram to predict 1-year overall survival

PURPOSE

This study aimed to determine the value of radiomics features derived from baseline computed tomography (CT) scans and volumetric measurements to predict overall survival (OS) in patients with nonsurgical pancreatic ductal adenocarcinoma (PDAC) treated with a chemotherapy combination regimen of 5-fluorouracil, leucovorin, irinotecan, and oxaliplatin (FOLFIRINOX).

METHODS

In this retrospective single-institution study, 131 patients with nonsurgical PDAC who received FOLFIRINOX neoadjuvant chemotherapy between December 2012 and November 2021 were included. Pretreatment contrast-enhanced CT images were obtained for all patients before inclusion. The primary tumor was contoured by an expert radiologist with 25 years of experience. A total of 845 radiomics features, including first-, second-, and higher-order features, were extracted from the total tumor volume. A feature reduction pipeline was used to reduce the dimensionality of the data. The selected features were used to generate a radiomics score based on the Least Absolute Shrinkage and Selection Operator coefficients. A high-dimensional Cox model was generated on the basis of the radiomics score and other quantitative and semantic imaging findings.

RESULTS

From the 845 radiomics features extracted, 45 were significantly different between the tertiles. The following equation was used to generate a radiomics score: radiomics score = SmallAreaEmphasis (-66.87801 + LargeDependenceEmphasis) - 0.2345916. The radiomics score was significantly different among the 3 groups of the radiomics features (P = .034). The overall difference in survival was significant among the 3 groups (P = .02). The nomogram showed good calibration and showed significant differences among the patients when they were classified as tertiles (P < .00).

CONCLUSION

Radiomics approaches have the potential to predict OS in nonsurgical patients with PDAC, and the inclusion of semantic imaging findings and pathologic data could further enhance prognostication in patients with PDAC.

Pancreatic Body and Tail Adenocarcinoma: Upfront Resection Versus Neoadjuvant Therapy, A Contemporary Analysis

OBJECTIVES

There is a paucity of data regarding the use of neoadjuvant therapy in pancreatic body or tail ductal adenocarcinomas. Given the differing tumor biology and aggressive nature of pancreatic body or tail adenocarcinomas, patients presenting with these tumors may benefit from upfront resection.

METHODS

A retrospective cohort study was performed analyzing patients who underwent distal pancreatectomy for pancreatic ductal adenocarcinoma between January 2013 and June 2022. Patients who underwent upfront resection were compared with those who underwent neoadjuvant therapy.

RESULTS

Forty-one patients underwent upfront distal pancreatectomy, whereas 40 patients underwent neoadjuvant therapy before curative intent resection. Neoadjuvant therapy did not improve overall survival (37 vs 34 months, P = 0.962) or disease-free survival (13 vs 15 months, P = 0.414), as compared with upfront resection. There was no significant difference in the rate or R 0 resection or postoperative outcomes.

CONCLUSION

No significant improvement in survival was demonstrated for patients undergoing neoadjuvant therapy for pancreatic ductal adenocarcinoma of the pancreatic body or tail when compared with upfront resection. Considering the potential for disease progression given the more aggressive tumor biology of pancreatic body and tail adenocarcinomas, appropriate surgical candidates should be offered upfront resection to provide the best chance of survival and cure.

Laparoscopic pancreatoduodenectomy is safe for the treatment of pancreatic ductal adenocarcinoma treated by chemoradiotherapy compared with open pancreatoduodenectomy: A matched case-control study

BACKGROUND

Few studies compared laparoscopic and open pancreatoduodenectomy for pancreatic ductal adenocarcinoma after neoadjuvant chemoradiotherapy.

METHODS

Retrospective cohort of patients who underwent laparoscopic or open pancreatoduodenectomy for resectable or borderline resectable pancreatic ductal adenocarcinoma after chemoradiotherapy between 2012 and 2023 was analyzed. Open pancreatoduodenectomy patients could theoretically benefit from the laparoscopic approach. We used a 1:2 (laparoscopic-to-open pancreatoduodenectomy) propensity score matching analysis stratified on age, gender, and body mass index.

RESULTS

We included 128 patients (33 laparoscopic and 95 open pancreatoduodenectomy), and after propensity score matching, 33 laparoscopic pancreatoduodenectomy and 66 open pancreatoduodenectomy were compared. There was no difference in demographic data except for lower tobacco use in laparoscopic pancreatoduodenectomy group (9% vs 30%, P = .023) with similar clinical presentation. Laparoscopic pancreatoduodenectomy compared to open pancreatoduodenectomy showed a longer median operative duration (380 vs 255 minutes, P < .001), shorter median length of resected vein (15 vs 23 mm, P = .01), longer median venous clamping time (29 vs 15 minutes, P = .005), similar median blood loss (300 vs 300 mL, P = .223), similar rate of hard pancreas (97% vs 85%, P = .094), and a larger median size of Wirsung duct (5 vs 4 mm, P = .02). Postoperative outcomes showed similar 90-day mortality rates (3% vs 3%, P > .99), Clavien-Dindo III-IV complications (6% vs 14%, P = .158), median lengths of hospital stay (12 vs 13 days, P = .409), and readmission rates (9% vs 18%, P = .366). Pathologic data showed similar R0 resection rates (88% vs 82%, P = .568). With a similar rate of adjuvant chemotherapy (P = .324) and shorter median follow-up with laparoscopic pancreatoduodenectomy (18 vs 34 months, P = .004), 3-year overall (P = .768) and disease-free (P = .839) survival rates were similar.

CONCLUSION

In selected patients, laparoscopic pancreatoduodenectomy for pancreatic ductal adenocarcinoma after neoadjuvant chemoradiotherapy appears to be safe and feasible when performed in experienced centers.

Survival Outcomes According to NCCN Criteria for Resection Following Neoadjuvant Therapy for Patients with Localized Pancreatic Cancer

BACKGROUND

This study aimed to assess the prognostic value of the National Comprehensive Cancer Network (NCCN) criteria for resection following neoadjuvant therapy for patients with localized pancreatic ductal adenocarcinoma (PDAC).

METHODS

This retrospective single-center study assessed 193 consecutive patients with localized PDAC (104 males and 89 females; mean age, 61.1 ± 9.4 years) who underwent neoadjuvant therapy followed by surgery between January 2010 and March 2021. Combined resectability and carbohydrate antigen (CA) 19-9 evaluation before and after neoadjuvant therapy was used to determine whether patients were eligible for resection according to the NCCN criteria. Post-surgical overall survival (OS), recurrence free survival (RFS), and pathologic results were evaluated and compared between patients considered eligible according to the NCCN criteria and those considered ineligible. Preoperative factors associated with better OS and RFS also were investigated.

RESULTS

Of the 193 patients, 168 (87.0 %) were eligible for resection according to the NCCN criteria. The patients eligible according to the NCCN criteria showed marginally longer OS than those considered ineligible (p = 0.056). After adjustment of variables, meeting the NCCN criteria for resection was an independent predictor of better OS (hazard ratio, 0.57; 95 % confidence interval, 0.34-0.96; p = 0.034). The two groups had similar RFS. Lower T-staging (T2 or less) and less lympho-vascular invasion and peri-neural invasion were noted in the patients who met the NCCN criteria (p ≤ 0.045).

CONCLUSIONS

The patients eligible for resection according to the NCCN criteria showed a trend toward longer OS and better pathologic results than the patients considered ineligible.

Recurrence scoring system predicting early recurrence for patients with pancreatic ductal adenocarcinoma undergoing pancreatectomy and portomesenteric vein resection

BACKGROUND

Pancreatectomy with concomitant portomesenteric vein resection (PVR) enables patients with portomesenteric vein (PV) involvement to achieve radical resection of pancreatic ductal adenocarcinoma, however, early recurrence (ER) is frequently observed.

AIM

To predict ER and identify patients at high risk of ER for individualized therapy.

METHODS

Totally 238 patients undergoing pancreatectomy and PVR were retrospectively enrolled and were allocated to the training or validating cohort. Univariate Cox and LASSO regression analyses were performed to construct serum recurrence score (SRS) based on 26 serum-derived parameters. Uni- and multivariate Cox regression analyses of SRS and 18 clinicopathological variables were performed to establish a Nomogram. Receiver operating characteristic curve analysis was used to evaluate the predictive accuracy. Survival analysis was performed using Kaplan-Meier method and log-rank test.

RESULTS

Independent serum-derived recurrence-relevant factors of LASSO regression model, including postoperative carbohydrate antigen 19-9, postoperative carcinoembryonic antigen, postoperative carbohydrate antigen 125, preoperative albumin (ALB), preoperative platelet to ALB ratio, and postoperative platelets to lymphocytes ratio, were used to construct SRS [area under the curve (AUC): 0.855, 95%CI: 0.786-0.924]. Independent risk factors of recurrence, including SRS [hazard ratio (HR): 1.688, 95%CI: 1.075-2.652], pain (HR: 1.653, 95%CI: 1.052-2.598), perineural invasion (HR: 2.070, 95%CI: 0.827-5.182), and PV invasion (HR: 1.603, 95%CI: 1.063-2.417), were used to establish the recurrence nomogram (AUC: 0.869, 95%CI: 0.803-0.934). Patients with either SRS > 0.53 or recurrence nomogram score > 4.23 were considered at high risk for ER, and had poor long-term outcomes.

CONCLUSION

The recurrence scoring system unique for pancreatectomy and PVR, will help clinicians in predicting recurrence efficiently and identifying patients at high risk of ER for individualized therapy.

Oncogenic GALNT5 confers FOLFIRINOX resistance via activating the MYH9/ NOTCH/ DDR axis in pancreatic ductal adenocarcinoma

Chemotherapy resistance has been a great challenge in pancreatic ductal adenocarcinoma(PDAC) treatments. Current first-line chemotherapy regimens for PDAC include gemcitabine-based regimens such as AG regimen (albumin paclitaxel and gemcitabine), fluorouracil-based regiments such as FOLFIRINOX regimen ((5-fluorouracil5-FU), oxaliplatin, Irinotecan) and platinum-based regimens for patients with BRCA mutations. large amounts of work have been done on exploring the mechanism underlying resistance of gemcitabine-based and platinum-based regimens, while little research has been achieved on the mechanism of FOLFIRINOX regimens resistance. Hence, we identified Polypeptide N-Acetylgalactosaminyltransferase 5, (GALNT5) as a vital regulator and a potential therapeutic target in FOLFIRINOX regimens resistance. Colony formation assays and flow cytometry assays were performed to explore the roles of GALNT5 in cell proliferation and apoptosis in PDAC treated with FOLFIRINOX. IC50 alterations were calculated in GALNT5 knockdown and overexpressed cell lines. RNA-seq followed by GSEA (gene set enrichment analysis) was displayed to explore the potential mechanism. WB (western blotting), real-time PCR, and IF (immunofluorescence) were performed to validate relative pathways. The mouse orthotopic xenograft PDAC model was established to examine GALNT5 functions in vivo. GALNT5 was highly expressed in PDAC tissues and predicted poor prognosis in PDAC. Upregulation of GALNT5 in PDAC cells conferred FOLFIRINOX resistance on PDAC by inhibiting DNA damage. Moreover, GALNT5 interacted with MYH9, thus participating in the activation of the NOTCH pathways, resulting in hampering FOI-induced DNA damage. Functions of GALNT5 promoting FOLFIRINOX resistance were validated in vivo. In this study, we found that aberrantly overexpressed GALNT5 in PDAC took part in the activation of the NOTCH pathway by interacting with MYH9, thus inhibiting the DDR to achieve FOLFIRINOX resistance and causing poor prognosis. We identified GALNT5 as a potential therapeutic target for PDAC patients resistant to FOLFIRINOX chemotherapy.

Canadian National Pancreas Conference 2023: A Review of Multidisciplinary Engagement in Pancreatic Cancer Care

Pancreatic cancer is a complex malignancy associated with poor prognosis and high symptom burden. Optimal patient care relies on the integration of various sectors in the healthcare field as well as innovation through research. The Canadian National Pancreas Conference (NPC) was co-organized and hosted by Craig's Cause Pancreatic Cancer Society and The Royal College of Physicians and Surgeons in November 2023 in Montreal, Canada. The conference sought to bridge the gap between Canadian healthcare providers and researchers who share the common goal of improving the prognosis, quality of life, and survival for patients with pancreatic cancer. The accredited event featured discussion topics including diagnosis and screening, value-based and palliative care, pancreatic enzyme replacement therapy, cancer-reducing treatment, and an overview of the current management landscape. The present article reviews the NPC sessions and discusses the presented content with respect to the current literature.

Gastrointestinal cancer resistance to treatment: the role of microbiota

The most common illnesses that adversely influence human health globally are gastrointestinal malignancies. The prevalence of gastrointestinal cancers (GICs) is relatively high, and the majority of patients receive ineffective care since they are discovered at an advanced stage of the disease. A major component of the human body is thought to be the microbiota of the gastrointestinal tract and the genes that make up the microbiome. The gut microbiota includes more than 3000 diverse species and billions of microbes. Each of them has benefits and drawbacks and been demonstrated to alter anticancer medication efficacy. Treatment of GIC with the help of the gut bacteria is effective while changes in the gut microbiome which is linked to resistance immunotherapy or chemotherapy. Despite significant studies and findings in this field, more research on the interactions between microbiota and response to treatment in GIC are needed to help researchers provide more effective therapeutic strategies with fewer treatment complication. In this review, we examine the effect of the human microbiota on anti-cancer management, including chemotherapy, immunotherapy, and radiotherapy.

The Association between Sampling and Survival in Patients with Pancreatic Ductal Adenocarcinoma Who Received Neoadjuvant Therapy and Pancreaticoduodenectomy

Adequate sampling is essential to an accurate pathologic evaluation of pancreatectomy specimens resected for pancreatic ductal adenocarcinoma (PDAC) after neoadjuvant therapy (NAT). However, limited data are available for the association between the sampling and survival in these patients. We examined the association of the entire submission of the tumor (ESOT) and the entire submission of the pancreas (ESOP) with disease-free survival (DFS) and overall survival (OS), as well as their correlations with clinicopathologic features, for 627 patients with PDAC who received NAT and pancreaticoduodenectomy. We demonstrated that both ESOT and ESOP were associated with lower ypT, less frequent perineural invasion, and better tumor response (p < 0.05). ESOP was also associated with a smaller tumor size (p < 0.001), more lymph nodes (p < 0.001), a lower ypN stage (p < 0.001), better differentiation (p = 0.02), and less frequent lymphovascular invasion (p = 0.009). However, since ESOP and ESOT were primarily conducted for cases with no grossly identifiable tumor or minimal residual carcinoma in initial sections, potential bias cannot be excluded. Both ESOT and ESOP were associated with less frequent recurrence/metastasis and better DFS and OS (p < 0.05) in the overall study population. ESOP was associated with better DFS and better OS in patients with ypT0/ypT1 or ypN0 tumors and better OS in patients with complete or near-complete response (p < 0.05). ESOT was associated with better OS in patients with ypT0/ypT1 or ypN0 tumors (p < 0.05). Both ESOT and ESOP were independent prognostic factors for OS according to multivariate survival analyses. Therefore, accurate pathologic evaluation using ESOP and ESOT is associated with the prognosis in PDAC patients with complete or near-complete pathologic response and ypT0/ypT1 tumor after NAT.

Comparative Efficacy of 21 Treatment Strategies for Resectable Pancreatic Cancer: A Network Meta-Analysis

The primary treatment for operable pancreatic cancer (PC) involves surgery followed by adjuvant therapy. Nevertheless, perioperative or neoadjuvant chemotherapy (CT) may be used to mitigate the likelihood of recurrence and mortality. This network meta-analysis (NMA) assesses the comparative efficacy of various treatment approaches for resectable PC. A thorough search was carried out on January 31, 2023, encompassing PubMed/MEDLINE, Cochrane Library, and Embase databases. We incorporated randomized clinical trials (RCTs) that compared surgical interventions with or without (neo)adjuvant or perioperative therapies for operable PC. We conducted a fixed-effects Bayesian NMA. We presented the effect sizes in terms of hazard ratios (HRs) for overall survival (OS) along with 95% credible intervals (95% CrIs). The treatment was deemed statistically superior when the 95% credible interval (CrI) did not encompass a null value (hazard ratio < 1). Treatment rankings were established based on the surface under the cumulative ranking curve (SUCRA). A total of 24 studies were incorporated, comparing 21 treatments with surgery in isolation. Eleven treatments showed superior efficacy compared to surgery alone, with HRs ranging from 0.38 for perioperative treatments to 0.73 for adjuvant 5-fluorouracil. After the exclusion of studies conducted in Asia, it was found that the perioperative regimen of gemcitabine combined with nab-paclitaxel was the most effective regimen (SUCRA, p = 0.99). The findings endorse the utilization of perioperative CT, especially multi-agent CT, as the favored intervention for operable PC in Western nations.

Preoperative endoscopic ultrasound-guided biopsy for resectable pancreatic head tumors increases operative time but not complications - a single center cohort study

BACKGROUND

Endoscopic ultrasound-guided aspiration or biopsy allows preoperative confirmation of malignancy but is not necessary for resectable pancreatic cancer. Preoperative biopsy may induce pancreatitis, making surgery difficult and complex. Therefore, we performed a retrospective study to evaluate the association between preoperative endoscopic ultrasound-guided biopsy and surgical outcomes in patients with resectable pancreatic head tumors.

MATERIALS AND METHODS

A prospectively enrolled cohort from a single high-volume pancreatic center was analyzed. Between 2007 and 2019, a total of 518 patients with resectable pancreatic head tumors underwent pancreaticoduodenectomy. This analysis was performed to determine the association of preoperative endoscopic ultrasound-guided biopsy with operating time and major complications.

RESULTS

In 518 patients who received pancreaticoduodenectomy, 164 patients (31.6%) underwent preoperative endoscopic ultrasound-guided biopsy. Endoscopic ultrasound-guided biopsy increased surgical time (46.9 min, confidence interval: 25.1-68.8, P-value <0.05) without increasing complications (odds ratio: 0.53, confidence interval: 0.31-1.29, P-value=0.29).

CONCLUSION

Preoperative endoscopic ultrasound-guided biopsy for pancreatic head tumors may increase operative time but is not associated with an increased risk of mortality and complications.

Comparison of the different versions of NCCN guidelines for predicting margin-negative resection of pancreatic cancer in patients undergoing upfront surgery

OBJECTIVES

The purpose of this study was to compare the different versions of the National Comprehensive Cancer Network (NCCN) guidelines for defining resectability of pancreatic ductal adenocarcinoma (PDAC) in predicting margin-negative (R0) resection, and to assess inter-reader agreement.

METHODS

This retrospective study included 283 patients (mean age, 65.1 years ± 9.4 [SD]; 155 men) who underwent upfront pancreatectomy for PDAC between 2017 and 2019. Two radiologists independently determined the resectability on preoperative CT according to the 2017, 2019, and 2020 NCCN guidelines. The sensitivity and specificity for R0 resection were analyzed using a multivariable logistic regression analysis with generalized estimating equations. Inter-reader agreement was assessed using kappa statistics.

RESULTS

R0 resection was accomplished in 239 patients (84.5%). The sensitivity and specificity averaged across two readers were, respectively, 76.6% and 29.5% for the 2020 guidelines, 74.1% and 32.9% for the 2019 guidelines, and 72.6% and 34.1% for the 2017 guidelines. Compared with the 2020 guidelines, both 2019 and 2017 guidelines showed significantly lower sensitivity for R0 resection (p ≤ .009). Specificity was significantly higher with the 2017 guidelines (p = .043) than with the 2020 guidelines. Inter-reader agreements for determining the resectability of PDCA were strong (k ≥ 0.83) with all guidelines, being highest with the 2020 guidelines (k = 0.91).

CONCLUSION

The 2020 NCCN guidelines showed significantly higher sensitivity for prediction of R0 resection than the 2017 and 2019 guidelines.

Variation in outcomes and practice patterns among patients with localized pancreatic cancer: the impact of the pancreatic cancer multidisciplinary clinic

Introduction

Patients with localized pancreatic adenocarcinoma (PDAC) benefit from multi-modality therapy. Whether care patterns and oncologic outcomes vary if a patient was seen through a pancreatic multi-disciplinary clinic (PMDC) versus only individual specialty clinics is unclear.

Methods

Using institutional Pancreatic Cancer Registry, we identified patients with localized PDAC from 2019- 2022 who eventually underwent resection. It was our standard practice for borderline resectable (BRPC) patients to undergo ≤4 months of neoadjuvant chemotherapy, ± radiation, followed by exploration, while locally advanced (LAPC) patients were treated with 4-6 months of chemotherapy, followed by radiation and potential exploration. Descriptive and multivariable analyses (MVA) were performed to examine the association between clinic type (PMDC vs individual specialty clinics i.e. surgical oncology, medical oncology, or radiation oncology) and study outcomes.

Results

A total of 416 patients met inclusion criteria. Of these, 267 (64.2%) had PMDC visits. PMDC group received radiation therapy more commonly (53.9% versus 27.5%, p=0.001), as compared to individual specialty clinic group. Completion of neoadjuvant treatment (NAT) was far more frequent in patients seen through PMDC compared to patients seen through individual specialty clinics (69.3% vs 48.9%). On MVA, PMDC group was significantly associated with receipt of NAT per institutional standards (adjusted OR 2.23, 95% CI 1.46-7.07, p=0.006). Moreover, the average treatment effect of PMDC on progression-free survival (PFS) was 4.45 (95CI: 0.87-8.03) months. No significant association between overall survival (OS) and clinic type was observed.

Discussion

Provision of care through PMDC was associated with significantly higher odds of completing NAT per institutional standards as compared to individual specialty clinics, which possibly translated into improved PFS. The development of multidisciplinary clinics for management of pancreatic cancer should be incentivized, and any barriers to such development should be addressed.

Identification of tumour regression in neoadjuvantly treated pancreatic cancer is based on divergent and nonspecific criteria

AIMS

Following the increased use of neoadjuvant therapy for pancreatic cancer, grading of tumour regression (TR) has become part of routine diagnostics. However, it suffers from marked interobserver variation, which is mainly ascribed to the subjectivity of the defining criteria of the categories in TR grading systems. We hypothesized that a further cause for the interobserver variation is the use of divergent and nonspecific morphological criteria to identify tumour regression.

METHODS AND RESULTS

Twenty treatment-naïve pancreatic cancers and 20 pancreatic cancers treated with neoadjuvant chemotherapy were reviewed by three experienced pancreatic pathologists who, blinded for treatment status, categorized each tumour as treatment-naïve or neoadjuvantly treated, and annotated all tissue areas they considered showing tumour regression. Only 50%-65% of the cases were categorized correctly, and the annotated tissue areas were highly discrepant (only 3%-41% overlap). When the prevalence of various morphological features deemed to indicate TR was compared between treatment-naïve and neoadjuvantly treated tumours, only one pattern, characterized by reduced cancer cell density and prominent stroma affecting a large area of the tumour bed, occurred significantly more frequently, but not exclusively, in the neoadjuvantly treated group. Finally, stromal features, both morphological and biological, were investigated as possible markers for tumour regression, but failed to distinguish TR from native tumour stroma.

CONCLUSION

There is considerable divergence in opinion between pathologists when it comes to the identification of tumour regression. Reliable identification of TR is only possible if it is extensive, while lesser degrees of treatment effect cannot be recognized with certainty.

Results of a Randomized Clinical Study of Gemcitabine Plus Nab-Paclitaxel Versus Gemcitabine Plus S-1 as Neoadjuvant Chemotherapy for Resectable and Borderline Resectable Pancreatic Ductal Adenocarcinoma (RCT, CSGO-HBP-015)

BACKGROUND

The optimal neoadjuvant chemotherapy (NAC) regimen for patients with localized pancreatic ductal adenocarcinoma (PDAC) remains uncertain. This trial aimed to evaluate the efficacy and safety of two neoadjuvant chemotherapy (NAC) regimens, gemcitabine plus nab-paclitaxel (GA) and gemcitabine plus S-1 (GS), in patients with resectable/borderline-resectable (R/BR) PDAC.

PATIENTS AND METHODS

Treatment-naïve patients with R/BR-PDAC were enrolled and randomly allocated. They received two cycles (2 months) of each standard protocol, followed by radical surgery for those without tumor progression in general hospitals belonging to our intergroup. The primary endpoint was to determine the superior regimen on the basis of achieving a 10% increase in the rate of patients with progression-free survival (PFS) at 2 years from allocation.

RESULTS

A total of 100 patients were enrolled, with 94 patients randomly assigned to the GS arm (N = 46) or GA arm (N = 48). The 2-year PFS rates did not show the stipulated difference [GA, 31% (24-38%)/GS, 26% (18-33%)], but the Kaplan-Myer analysis showed significance (median PFS, GA/GS 14 months/9 months, P = 0.048; HR 0.71). Secondary endpoint comparisons yielded the following results (GA/GS arm, P-value): rates of severe adverse events during NAC, 73%/78%, P = 0.55; completion rates of the stipulated NAC, 92%/83%, P = 0.71; resection rates, 85%/72%, P = 0.10; average tumor marker (CA19-9) reduction rates, -50%/-21%, P = 0.01; average numbers of lymph node metastasis, 1.7/3.2, P = 0.04; and median overall survival times, 42/22 months, P = 0.26.

CONCLUSIONS

This study found that GA and GS are viable neoadjuvant treatment regimens in R/BR-PDAC. Although the GA group exhibited a favorable PFS outcome, the primary endpoint was not achieved.

Total Neoadjuvant Therapy in Localized Pancreatic Cancer: Is More Better?

Pancreatic ductal adenocarcinoma (PDAC) poses a significant challenge in oncology due to its advanced stage upon diagnosis and limited treatment options. Surgical resection, the primary curative approach, often results in poor long-term survival rates, leading to the exploration of alternative strategies like neoadjuvant therapy (NAT) and total neoadjuvant therapy (TNT). While NAT aims to enhance resectability and overall survival, there appears to be potential for improvement, prompting consideration of alternative neoadjuvant strategies integrating full-dose chemotherapy (CT) and radiotherapy (RT) in TNT approaches. TNT integrates chemotherapy and radiotherapy prior to surgery, potentially improving margin-negative resection rates and enabling curative resection for locally advanced cases. The lingering question: is more always better? This article categorizes TNT strategies into six main groups based on radiotherapy (RT) techniques: (1) conventional chemoradiotherapy (CRT), (2) the Dutch PREOPANC approach, (3) hypofractionated ablative intensity-modulated radiotherapy (HFA-IMRT), and stereotactic body radiotherapy (SBRT) techniques, which further divide into (4) non-ablative SBRT, (5) nearly ablative SBRT, and (6) adaptive ablative SBRT. A comprehensive analysis of the literature on TNT is provided for both borderline resectable pancreatic cancer (BRPC) and locally advanced pancreatic cancer (LAPC), with detailed sections for each.

Contemporary report of surgical outcomes after single-stage total pancreatectomy: A 10-year experience

BACKGROUND

Surgeons rarely perform elective total pancreatectomy (TP). Our study seeks to report surgical outcomes in a contemporary series of single-stage (SS) TP patients.

METHODS

Between the years 2013 to 2023 we conducted a retrospective review of 60 consecutive patients who underwent SSTP. Demographics, pathology, treatment-related variables, and survival were recorded and analyzed.

RESULTS

SSTP consisted of 3% (60/1859) of elective pancreas resections conducted. Patient median age was 68 years. Ninety percent of these patients (n = 54) underwent SSTP for pancreatic ductal adenocarcinoma (PDAC). Conversion from a planned partial pancreatectomy to TP occurred intraoperatively in 31 (52%) patients. Fifty-nine patients (98%) underwent an R0 resection. Median length of hospital stay was 6 days. The majority of morbidities were minor, with 27% patients (n = 16) developing severe complications (Clavien-Dindo ≥3). Thirty and ninety-day mortality rates were 1.67% (one patient) and 5% (three patients), respectively. Median survival for the entire cohort was 24.4 months; 22.7 months for PDAC patients, with 1-, 3-, and 5-year survival of 68%, 43%, and 16%, respectively. No mortality occurred in non-PDAC patients (n = 6).

CONCLUSION

Elective single-stage total pancreatectomy can be a safe and appropriate treatment option. SSTP should be in the armamentarium of surgeons performing pancreatic resection.

Advances in Surgery and (Neo) Adjuvant Therapy in the Management of Pancreatic Cancer

A multimodality approach, which usually includes chemotherapy, surgery, and/or radiotherapy, is optimal for patients with localized pancreatic cancer. The timing and sequence of these interventions depend on anatomic resectability and the biological suitability of the tumor and the patient. Tumors with vascular involvement (ie, borderline resectable/locally advanced) require surgical reassessments after therapy and participation of surgeons familiar with advanced techniques. When indicated, venous reconstruction should be offered as standard of care because it has acceptable morbidity. Morbidity and mortality of pancreas surgery may be mitigated when surgery is performed at high-volume centers.

Construction of S100 family members prognosis prediction model and analysis of immune microenvironment landscape at single-cell level in pancreatic adenocarcinoma: a tumor marker prognostic study

Pancreatic adenocarcinoma characterized by a mere 10% 5-year survival rate, poses a formidable challenge due to its specific anatomical location, making tumor tissue acquisition difficult. This limitation underscores the critical need for novel biomarkers to stratify this patient population. Accordingly, this study aimed to construct a prognosis prediction model centered on S100 family members. Leveraging six S100 genes and their corresponding coefficients, an S100 score was calculated to predict survival outcomes. The present study provided comprehensive internal and external validation along with power evaluation results, substantiating the efficacy of the proposed model. Additionally, the study explored the S100-driven potential mechanisms underlying malignant progression. By comparing immune cell infiltration proportions in distinct patient groups with varying prognoses, the research identified differences driven by S100 expression. Furthermore, the analysis explored significant ligand-receptor pairs between malignant cells and immune cells influenced by S100 genes, uncovering crucial insights. Notably, the study identified a novel biomarker capable of predicting the sensitivity of neoadjuvant chemotherapy, offering promising avenues for further research and clinical application.

Correlation between Angiotensin Inhibitor Administration and Longer Survival in Patients Who Underwent Curative Resection for Pancreatic Cancer

PURPOSE

The microenvironment of pancreatic ductal adenocarcinoma (PDAC) with extensive desmoplastic stroma contributes to aggressive cancer behavior. Angiotensin system inhibitors (ASIs) reduce stromal fibrosis and are a promising therapeutic strategy. The purpose of this study was to examine how ASIs affected the oncological results of patients who had their PDAC removed.

MATERIALS AND METHODS

A retrospective assessment was conducted on the clinicopathological and survival data of patients who received curative resection for PDAC at Severance Hospital between January 2012 and December 2019.

RESULTS

A total of 410 participants (228 male and 182 female), with a median follow-up period of 12.8 months, were included in this study. Patients were divided into three groups, based on ASI use and history of hypertension: group 1, normotensive and never used ASI (n=210, 51.2%); group 2, ASI non-users with hypertension (n=50, 12.2%); and group 3, ASI users with hypertension (n=150, 36.6%). The three groups did not differ significantly in terms of age, sex, kind of operation, T and N stages, or adjuvant and neoadjuvant therapy. Moreover, there was no discernible difference in disease-free survival between those who used ASI and those who did not (p=0.636). The 5-year overall survival (OS) rates in groups 1, 2, and 3 were 52.6%, 32.3%, and 38.0%, respectively. However, the OS rate of ASI users was remarkably higher than that of non-users (p=0.016).

CONCLUSION

In patients with resected PDAC, ASI is linked to longer survival rates. Furthermore, for individuals with hypertension, ASI in conjunction with conventional chemotherapy may be an easy and successful treatment option.

Comparing upfront surgery with neoadjuvant treatments in patients with resectable, borderline resectable or locally advanced pancreatic cancer: a systematic review and network meta-analysis of randomized clinical trials

BACKGROUND

The aim was to explore the optimal neoadjuvant therapy strategy for resectable, borderline resectable, and locally advanced pancreatic cancer, in order to provide a theoretical basis for the development of new neoadjuvant treatment protocols for clinical use.

PATIENTS AND METHODS

The authors reviewed literature titles and abstracts comparing three treatment strategies (neoadjuvant chemoradiotherapy, neoadjuvant chemotherapy, and upfront surgery) in PubMed, Embase, The Cochrane Library, Web of Science from 2009 to 2023 to estimate relative odds ratios for resection rate and hazard ratios (HRs) for overall survival (OS) in all include trials.

RESULTS

A total of nine studies involving 889 patients were included in the analysis. The treatment methods included upfront surgery, neoadjuvant chemotherapy, and neoadjuvant chemoradiotherapy followed by surgery. The network meta-analysis results demonstrated that neoadjuvant chemoradiotherapy followed by surgery was an effective approach in improving OS for resectable and borderline resectable pancreatic cancer (RPC) patients compared to upfront surgery (HR: 0.79, 95% CI: 0.64-0.98) and neoadjuvant chemotherapy (HR: 0.79, 95% CI: 0.64-0.98). Additionally, neoadjuvant chemoradiotherapy significantly increased the margin negative resection (R0) rate and pathological negative lymph node (pN0) rate in patients with resectable and borderline RPC. However, it is worth noting that neoadjuvant chemoradiotherapy increased the risk of grade 3 or higher treatment-related adverse events, including in patients with locally advanced pancreatic cancer.

CONCLUSIONS

The current evidence suggests that neoadjuvant chemoradiotherapy followed by surgery is the optimal choice for treating patients with resectable and borderline RPC. Future research should focus on optimizing neoadjuvant chemoradiotherapy regimens to effectively improve OS while reducing the occurrence of adverse events.

Systemic treatments in pancreatic cancer: Taiwan pancreas society recommendation

Pancreatic cancer is a highly aggressive malignancy with a poor prognosis. Over the past decade, significant therapeutic advancements have improved the survival rates of patients with pancreatic cancer. One of the primary factors contributing to these positive outcomes is the evolution of chemotherapy, from monotherapy to doublet or triplet regimens, and the integration of multimodal approaches. Additionally, targeted agents tailored to patients with specific genetic alterations and the development of cell therapies show promise in benefiting certain subpopulations. This article focuses on examining pivotal studies that explore the role of chemotherapy in neoadjuvant, adjuvant, maintenance, and salvage settings; highlights interesting findings related to cell therapy; and provides an overview of ongoing trials concerning metastatic settings. This review primarily aimed to offer recommendations based on therapeutic evidence, recent advancements in new treatment combinations, and the most innovative approaches. A unique aspect of this review is the inclusion of published papers on clinical trials and real-world data in Taiwan, thus adding a valuable perspective to the overall analysis.

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

Backgrounds/Aims

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).

Methods

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.

Results

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.

Conclusions

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.

Neoadjuvant Therapy in Borderline Resectable Pancreatic Cancer

In this perspective, we present our assessment of all of the known accumulated evidence on the role of neoadjuvant therapy in the management of borderline resectable pancreatic cancer highlighting the gaps in the data, the current regimens used and providing a brief insight into the way forward.

Adjuvant Therapy After Upfront Resection of Resectable Pancreatic Cancer: Patterns of Omission and Use-A Prospective Real-Life Study

BACKGROUND

Little is known about adjuvant therapy (AT) omission and use outside of randomized trials. We aimed to assess the patterns of AT omission and use in a cohort of upfront resected pancreatic cancer patients in a real-life scenario.

METHODS

From January 2019 to July 2022, 317 patients with resected pancreatic cancer and operated upfront were prospectively enrolled in this prospective observational trial according to the previously calculated sample size. The association between perioperative variables and the risk of AT omission and AT delay was analyzed using multivariable logistic regression.

RESULTS

Eighty patients (25.2%) did not receive AT. The main reasons for AT omission were postoperative complications (38.8%), oncologist's choice (21.2%), baseline comorbidities (20%), patient's choice (10%), and early recurrence (10%). At the multivariable analysis, the odds of not receiving AT increased significantly for older patients (odds ratio [OR] 1.1, p < 0.001), those having an American Society of Anesthesiologists score ≥II (OR 2.03, p = 0.015), or developing postoperative pancreatic fistula (OR 2.5, p = 0.019). The likelihood of not receiving FOLFIRINOX as AT increased for older patients (OR 1.1, p < 0.001), in the presence of early-stage disease (stage I-IIa vs. IIb-III, OR 2.82, p =0.031; N0 vs. N+, OR 3, p = 0.03), and for patients who experienced postoperative major complications (OR 4.7, p = 0.009). A twofold increased likelihood of delay in AT was found in patients experiencing postoperative complications (OR 3.86, p = 0.011).

CONCLUSIONS

AT is not delivered in about one-quarter of upfront resected pancreatic cancer patients. Age, comorbidities, and postoperative complications are the main drivers of AT omission and mFOLFIRINOX non-use.

CLINICALTRIALS REGISTRATION

NCT03788382.

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.

Fat malabsorption in pancreatic cancer: Pathophysiology and management

Exocrine pancreatic insufficiency (EPI) is common in pancreatic ductal adenocarcinoma (PDAC) and may lead to significant nutrition compromise. In the setting of cancer cachexia and gastrointestinal toxicities of cancer treatments, untreated (or undertreated) EPI exacerbates weight loss, sarcopenia, micronutrient deficiencies, and malnutrition. Together, these complications contribute to poor tolerance of oncologic therapies and negatively impact survival. Treatment of EPI in PDAC involves the addition of pancreatic enzyme replacement therapy, with titration to improve gastrointestinal symptoms. Medical nutrition therapies may also be applicable and may include fat-soluble vitamin replacement, medium-chain triglycerides, and, in some cases, enteral nutrition. Optimizing nutrition status is an important adjunct treatment approach to improve quality of life and may also improve overall survival.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

The impact of surgical-oncologic textbook outcome in patients with stage I to III pancreatic ductal adenocarcinoma: A cross-validation study of two national registries

BACKGROUND

Using national registries, we aimed to evaluate oncologic textbook outcomes in pancreatic ductal adenocarcinoma patients.

METHODS

Patients with stage I to III pancreatic ductal adenocarcinoma and surgical resection from 2010 to 2020 in the US and Germany were identified using the National Cancer Database and National Cancer Registries data. The surgical-oncologic textbook outcome was defined as complete oncologic resection with no residual tumor and ≥12 harvested lymph nodes. The composite endpoint was defined as surgical-oncologic textbook outcome and receipt of perioperative systemic and/or radiation therapy.

RESULTS

In total, 33,498 patients from the National Cancer Database and 14,589 patients from the National Cancer Registries were included. In the National Cancer Database, 28,931 (86%) patients had complete oncologic resection with no residual tumor, and 11,595 (79%) in the National Cancer Registries. 8,723 (26%) patients in the National Cancer Database and 556 (4%) in the National Cancer Registries had <12 lymph nodes harvested. The National Cancer Database shows 26,135 (78%) underwent perioperative therapy and 8,333 (57%) in the National Cancer Registries. Surgical-oncologic textbook outcome was achieved in 21,198 (63%) patients in the National Cancer Database and in 11,234 (77%) patients from the National Cancer Registries. 16,967 (50%) patients in the National Cancer Database and 7,878 (54%) patients in the National Cancer Registries had composite textbook outcome. Median overall survival in patients with composite textbook outcomes was 32 months in the National Cancer Database and 27 months in the National Cancer Registries (P < .001). In contrast, those with non-textbook outcomes had a median overall survival of 23 months in the National Cancer Database and 20 months in the National Cancer Registries (P < .001).

CONCLUSION

Surgical-oncologic textbook outcomes were achieved in > 50% of stage I to III pancreatic ductal adenocarcinoma for both the National Cancer Database and the National Cancer Registries. Failure to achieve textbook outcomes was associated with impaired survival across both registries.

Fully covered self-expandable metallic stents versus plastic stents for preoperative biliary drainage in patients with pancreatic head cancer and the risk factors for post-endoscopic retrograde cholangiopancreatography pancreatitis

Objectives

Optimal stents for preoperative biliary drainage (PBD) for patients with possible resectable pancreatic cancer remain controversial, and risk factors for post-endoscopic retrograde cholangiopancreatography pancreatitis (PEP), followed by PBD, are unknown. In this study, the efficacy and safety of fully covered self-expandable metallic stents (FCSEMSs) and plastic stents (PSs) were compared, and the risk factors for PEP, followed by PBD, were investigated for patients with pancreatic cancer.

Methods

Consecutive patients with pancreatic cancer who underwent PBD between April 2005 and March 2022 were included. We retrospectively evaluated recurrent biliary obstruction, adverse events (AEs), and postoperative complications for FCSEMS and PS groups and investigated the risk factors for PEP.

Results

A total of 105 patients were included. There were 20 patients in the FCSEMS group and 85 patients in the PS group. For the FCSEMS group, the rate of recurrent biliary obstruction (0% vs. 25%, p = 0.03) was significantly lower. There was no difference in AE between the two groups. No significant differences were observed in the overall postoperative complications, but the volume of intraoperative bleeding was larger for the PS group than it was for the FCSEMS group (p < 0.001). From multivariate analysis, being female and lack of main pancreatic duct dilation were independent risk factors for pancreatitis (odds ratio, 5.68; p = 0.028; odds ratio, 4.91; p = 0.048).

Conclusions

FCSEMSs are thought to be preferable to PSs for PBD due to their longer time to recurrent biliary obstruction. Being female and the lack of main pancreatic duct dilation were risk factors for PEP.

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

BACKGROUND

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.

METHODS

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.

RESULTS

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%).

CONCLUSION

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.

Identification of patients at high risk for recurrence in carcinoma of the ampulla of Vater: Analysis in 460 patients

Aim

Carcinoma of the ampulla of Vater (CAV) shows a favorable prognosis compared to that with the other periampullary tumors, while some cases have a poor prognosis. The aims of the present study are to clarify the clinicopathological factors associated with poor recurrence-free survival (RFS) in patients with CAV after curative resection and to validate the usefulness of adjuvant chemotherapy (AC).

Patients

The study design is a multicenter retrospective cohort study. Patients with CAV who underwent pancreaticoduodenectomy between January 2008 and December 2020 at 26 hospitals were analyzed. The 30 clinicopathological factors were evaluated. A propensity score matching (PSM) was used to compare between patients with and without AC.

Results

Finally, 460 patients were analyzed. Median duration of follow-up was 47.2 months. Twenty-one prognostic factors associated with poor RFS were identified by univariate analysis. In multivariate analysis, aged ≥71, tumor diameter ≥12 mm, pT2 or higher stage (pT≥2), portal vein invasion (PV+), venous invasion(V+), and node positive disease (pN+) were independent prognostic factors for poor RFS. Out of 80 patients who received AC, 63 patients were assigned to analysis for PSM. The results showed no beneficial effect of AC on RFS. The preoperative factors potentially predicting pT≥2, V+, and/or N+ were at least one of following; (1) CA19-9 > 37 IU/mL, (2) ulcerative or mixed type appearance, (3) except for well-differentiated tumor, or (4) except for intestinal subtype of histology.

Conclusions

Aged ≥71, tumor diameter ≥12 mm, pT≥2, PV+, V+, and pN+ were independent prognostic factors for poor RFS in patients with CAV. An additional therapeutic strategy may be desirable in CAV patients at high risk for recurrence.

How a significant increase in survival in pancreatic cancer is achieved. The role of nutritional status and supportive care: A review

Pancreatic cancer (PC) is a serious public health problem. The mortality rate of patients with PC remains one of the highest among cancers. Early diagnosis of PC is challenging, so it is often diagnosed in the later stages. Current treatment approaches, including surgery, neoadjuvant and adjuvant chemotherapy, chemoradiotherapy, and supportive care, have demonstrated improved outcomes. A significant problem remains exocrine pancreatic insufficiency (EPI) in patients with PC, which requires enzyme replacement therapy. However, this is not given due attention in the Russian literature. This review addresses the survival trends of patients with PC, current therapies, and enzyme replacement therapy as an integral part of supportive care and improvement of nutritional status; also, the issues of routing patients with PC are addressed. It is emphasized that the diagnosis and treatment of EPI are mandatory to improve and maintain the nutritional status and quality of life; failure to treat EPI renders antitumor treatment ineffective.

Neoadjuvant Chemotherapy Versus Upfront Surgery for Resectable Pancreatic Adenocarcinoma: An Updated Nationwide Study

OBJECTIVE

The objective of this study was to assess the association of survival with neoadjuvant chemotherapy (NAC) in resectable pancreatic adenocarcinoma (PDAC).

BACKGROUND

The early control of potential micrometastases and patient selection using NAC has been advocated for patients with PDAC. However, the role of NAC for resectable PDAC remains unclear.

METHODS

Patients with clinical T1 and T2 PDAC were identified in the National Cancer Database from 2010 to 2017. Kaplan-Meier estimates, and Cox regression models were used to compare survival. To address immortal time bias, landmark analysis was performed. Interactions between preoperative factors and NAC were investigated in subgroup analyses. A propensity score analysis was performed to compare survival between multiagent NAC and upfront surgery.

RESULTS

In total, 4041 patients were treated with upfront surgery and 1,175 patients were treated with NAC (79.4% multiagent NAC, 20.6% single-agent NAC). Using a landmark time of 6 months after diagnosis, patients treated with multiagent NAC had longer median overall survival compared with upfront surgery and single-agent NAC. (35.8 vs 27.1 vs 27.4 mo). Multiagent NAC was associated with lower mortality rates compared with upfront surgery (adjusted hazard ratio, 0.77; 95% CI, 0.70-0.85), whereas single-agent NAC was not. The association of survival with multiagent NAC were consistent in analyses using the matched data sets. Interaction analysis revealed that the association between multiagent NAC and a lower mortality rate did not significantly differ across age, facility type, tumor location, CA 19-9 levels, and clinical T/N stages.

CONCLUSIONS

The findings suggest that multiagent NAC followed by resection is associated with improved survival compared with upfront surgery.

Neoadjuvant chemotherapy for early-stage colon cancer

Surgery with or without adjuvant chemotherapy is the standard treatment for early-stage colon cancer. However, evidence has recently emerged for neoadjuvant chemotherapy, with the results of randomised clinical trials sparking debates within multidisciplinary teams and splitting the gastrointestinal oncology community. Further to a systematic search of the literature, we provide a thorough and in-depth analysis of the findings from these trials, highlighting the advantages and disadvantages of neoadjuvant chemotherapy. We conclude that, while there is a potential value of moving systemic therapy from the post-operative to the pre-operative setting, the available evidence does not justify a shift in the treatment paradigm of early-stage colon cancer, and surgery with or without adjuvant chemotherapy should remain the standard approach for these patients.

Anatomical and Biological Considerations to Determine Resectability in Pancreatic Cancer

Pancreatic ductal adenocarcinoma (PDAC) remains associated with poor outcomes with a 5-year survival of 12% across all stages of the disease. These poor outcomes are driven by a delay in diagnosis and an early propensity for systemic dissemination of the disease. Recently, aggressive surgical approaches involving complex vascular resections and reconstructions have become more common, thus allowing more locally advanced tumors to be resected. Unfortunately, however, even after the completion of surgery and systemic therapy, approximately 40% of patients experience early recurrence of disease. To determine resectability, many institutions utilize anatomical staging systems based on the presence and extent of vascular involvement of major abdominal vessels around the pancreas. However, these classification systems are based on anatomical considerations only and do not factor in the burden of systemic disease. By integrating the biological criteria, we possibly could avoid futile resections often associated with significant morbidity. Especially patients with anatomically resectable disease who have a heavy burden of radiologically undetected systemic disease most likely do not derive a survival benefit from resection. On the contrary, we could offer complex resections to those who have locally advanced or oligometastatic disease but have favorable systemic biology and are most likely to benefit from resection. This review summarizes the current literature on defining anatomical and biological resectability in patients with pancreatic cancer.

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

OBJECTIVES

To 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).

METHODS

A 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.

RESULTS

The 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.

CONCLUSIONS

The 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.

Complete Primary Pathological Response Following Neoadjuvant Treatment and Radical Resection for Pancreatic Ductal Adenocarcinoma

INTRODUCTION

Neoadjuvant treatment (NAT) for borderline (BD) or locally advanced (LA) primary pancreatic cancer (PDAC) is now a widely adopted approach. We present a case series of patients who have achieved a complete pathological response of the primary tumour on final histology following neoadjuvant chemotherapy +/- chemoradiation and radical surgery.

METHODS

Patients who underwent radical pancreatic resection following neoadjuvant treatment between March 2006 and March 2023 at a single institution were identified by retrospective case note review of a prospectively maintained database.

RESULTS

Ten patients were identified to have a complete primary pathological response (ypT0) on postoperative histology. Before treatment, five patients were considered BD and five were LA according to National Comprehensive Cancer Network guidelines. All patients underwent staging Computed Tomography (CT) and nine underwent 18Fluorodeoxyglucose Positron Emission Tomography (18FDG-PET/CT) imaging, with a mean maximum standardized uptake value (SUVmax) of the primary lesion at 6.14 ± 1.98 units. All patients received neoadjuvant chemotherapy, and eight received further chemoradiotherapy prior to resection. Mean pre- and post-neoadjuvant treatment serum Ca19-9 was 148.0 ± 146.3 IU/L and 18.0 ± 18.7 IU/L, respectively (p = 0.01). The mean duration of NAT was 5.6 ± 1.7 months. The mean time from completion of NAT to surgery was 13.1 ± 8.3 weeks. The mean lymph node yield was 21.1 ± 10.4 nodes, with one patient found to have 1 lymph node involved. All resections were reported to be R0. The mean length of stay was 11.8 ± 6.2 days. At the time of analysis, one death was reported at 35 months postoperatively. Two cases of recurrence were reported at 16 months (surgical bed) and 33 months (pulmonary). All other patients remain alive and under active surveillance. The current overall survival is 26.6 ± 20.7 months and counting.

CONCLUSIONS

Complete primary pathological response is uncommon but possible following neoadjuvant treatment in patients with PDAC. Further work to identify the common denominator within this unique cohort may lead to advances in the therapeutic approach and offer hope for patients diagnosed with borderline or locally advanced pancreatic ductal adenocarcinoma.