A Qualitative Review of Neoadjuvant Chemotherapy in Resectable Pancreatic Adenocarcinoma

Long-Term Outcomes of Neoadjuvant Therapy Versus Upfront Surgery for Resectable Pancreatic Ductal Adenocarcinoma

INTRODUCTION

This study aimed to compare the long-term effects of neoadjuvant therapy and upfront surgery on overall survival (OS) and progression-free survival (PFS) in patients with resectable pancreatic ductal adenocarcinoma (PDAC).

METHODS

We retrospectively analyzed 202 patients, including 167 who had upfront surgery and 35 who received neoadjuvant therapy followed by surgery. Surgical outcomes and survival rates were compared using propensity score matching to minimize selection bias.

RESULTS

Neoadjuvant therapy showed significantly longer 75% OS (72.7 months vs. 28.3 months, p = 0.032) and PFS (29.6 months vs. 13.2 months, p < 0.001) compared to upfront surgery. Additionally, neoadjuvant therapy demonstrated significant improvements in surgical outcomes, including higher R0 resection rates (74.3% vs. 49.5%, p = 0.034), reduced tumor size (22.0 mm vs. 28.0 mm, p = 0.001), and decreased lymphovascular invasion (20.0% vs. 52.4%, p = 0.001).

CONCLUSION

Our study demonstrates the potential benefits of neoadjuvant therapy for resectable PDAC. The improved survival rates, delayed disease progression, and enhanced surgical outcomes underscore the potential of neoadjuvant therapy in addressing this aggressive disease. Despite limitations such as the retrospective design and small sample size, these findings support the effectiveness of neoadjuvant therapy in improving treatment outcomes for PDAC patients in real-world settings. Further prospective studies are required to validate these results.

Impact of Neoadjuvant Therapy on Oncological Outcomes of Patients With Distal Pancreatic Adenocarcinoma

BACKGROUND

Distal pancreatic ductal adenocarcinoma (D-PDAC) often presents at an advanced stage. The efficacy of neoadjuvant therapy (NAT) in improving outcomes for D-PDAC is not well-established. This study evaluates the impact of NAT on the oncological outcomes of patients with D-PDAC.

METHODS

A retrospective cohort study of consecutive patients with resectable and borderline-resectable D-PDAC treated at a single center from 2012 to 2020 was performed. Stratification was based on initial treatment-NAT or surgery first (SF). Survival analysis, following intention-to-treat framework, used Kaplan-Meier and Cox regression to assess NAT's impact on progression-free survival (PFS) and overall survival (OS) of D-PDAC.

RESULTS

Among 141 patients (median age 69.8 years, 51.8% females) included in the study, 71 (50.4%) received NAT and 70 (49.6%) were planned for SF. Patients receiving NAT were younger (65.9 vs. 72.6 years) and had higher incidence of borderline-resectable disease (31% vs. 4.3%) (both p < 0.05) than those undergoing SF. Thirteen patients (18.3%) undergoing NAT and five (7.1%) in SF group, failed to undergo resection. Univariate comparison showed no difference in the PFS (SF:13.97 vs. NAT:17.00 months, p = 0.6), and OS (SF:23.73 vs. NAT:32.53 months, p = 0.35). Multivariate Cox regression analysis noted significantly improved PFS (HR = 0.64, 95%CI = 0.42-0.96, p = 0.031) and OS (HR = 0.60, 95%CI = 0.39-0.93, p = 0.021) with NAT.

CONCLUSION

NAT is associated with improved PFS and OS in patients with -D-PDAC. Further randomized controlled trials are warranted to confirm these findings.

Enhancing Neoadjuvant Virotherapy's Effectiveness by Targeting Stroma to Improve Resectability in Pancreatic Cancer

About one-fourth of patients with pancreatic ductal adenocarcinoma (PDAC) are categorized as borderline resectable (BR) or locally advanced (LA). Chemotherapy and radiation therapy have not yielded the anticipated outcomes in curing patients with BR/LA PDAC. The surgical resection of these tumors presents challenges owing to the unpredictability of the resection margin, involvement of vasculature with the tumor, the likelihood of occult metastasis, a higher ratio of positive lymph nodes, and the relatively larger size of tumor nodules. Oncolytic virotherapy has shown promising activity in preclinical PDAC models. Unfortunately, the desmoplastic stroma within the PDAC tumor microenvironment establishes a barrier, hindering the infiltration of oncolytic viruses and various therapeutic drugs-such as antibodies, adoptive cell therapy agents, and chemotherapeutic agents-in reaching the tumor site. Recently, a growing emphasis has been placed on targeting major acellular components of tumor stroma, such as hyaluronic acid and collagen, to enhance drug penetration. Oncolytic viruses can be engineered to express proteolytic enzymes that cleave hyaluronic acid and collagen into smaller polypeptides, thereby softening the desmoplastic stroma, ultimately leading to increased viral distribution along with increased oncolysis and subsequent tumor size regression. This approach may offer new possibilities to improve the resectability of patients diagnosed with BR and LA PDAC.

Technical Strategy for Pancreatic Body Cancers: A Raison d'etre of Distal Pancreatectomy with Portal Resection

BACKGROUND

Advancements in multiagent chemotherapy have expanded the surgical indications for pancreatic cancer. Although pancreaticoduodenectomy (PD) with portal vein resection (PVR) has become widely adopted, distal pancreatectomy (DP) with PVR remains rarely performed because of its technical complexity. This study was designed to assess the feasibility of DP-PVR compared with PD-PVR for pancreatic body cancers, with a focus on PV complications and providing optimal reconstruction techniques when DP-PVR is necessary.

METHODS

A retrospective review was conducted on consecutive pancreatic body cancer patients who underwent pancreatectomy with PVR between 2005 and 2020. An algorithm based on the anatomical relationship between the arteries and PV was used for optimal surgical selection.

RESULTS

Among 119 patients, 32 underwent DP-PVR and 87 underwent PD-PVR. Various reconstruction techniques were employed in DP-PVR cases, including patch reconstruction, graft interposition, and wedge resection. The majority of PD-PVR cases involved end-to-end anastomosis. The length of PVR was shorter in DP-PVR (25 vs. 40 mm; p < 0.001). Although Clavien-Dindo ≥3a was higher in DP-PVR (p = 0.002), inpatient mortality and R0 status were similar. Complete PV occlusion occurred more frequently in DP-PVR than in PD-PVR (21.9% vs. 1.1%; p < 0.001). A cutoff value of 30 mm for PVR length was determined to be predictive of nonrecurrence-related PV occlusion after DP-PVR. The two groups did not differ significantly in recurrence or overall survival.

CONCLUSIONS

DP-PVR had higher occlusion and postoperative complication rates than PD-PVR. These findings support the proposed algorithm and emphasize the importance of meticulous surgical manipulation when DP-PVR is deemed necessary.

Noninvasive Computed Tomography-Based Deep Learning Model Predicts In Vitro Chemosensitivity Assay Results in Pancreatic Cancer

OBJECTIVES

We aimed to predict in vitro chemosensitivity assay results from computed tomography (CT) images by applying deep learning (DL) to optimize chemotherapy for pancreatic ductal adenocarcinoma (PDAC).

MATERIALS AND METHODS

Preoperative enhanced abdominal CT images and the histoculture drug response assay (HDRA) results were collected from 33 PDAC patients undergoing surgery. Deep learning was performed using CT images of both the HDRA-positive and HDRA-negative groups. We trimmed small patches from the entire tumor area. We established various prediction labels for HDRA results with 5-fluorouracil (FU), gemcitabine (GEM), and paclitaxel (PTX). We built a predictive model using a residual convolutional neural network and used 3-fold cross-validation.

RESULTS

Of the 33 patients, effective response to FU, GEM, and PTX by HDRA was observed in 19 (57.6%), 11 (33.3%), and 23 (88.5%) patients, respectively. The average accuracy and the area under the receiver operating characteristic curve (AUC) of the model for predicting the effective response to FU were 93.4% and 0.979, respectively. In the prediction of GEM, the models demonstrated high accuracy (92.8%) and AUC (0.969). Likewise, the model for predicting response to PTX had a high performance (accuracy, 95.9%; AUC, 0.979).

CONCLUSIONS

Our CT patch-based DL model exhibited high predictive performance in projecting HDRA results. Our study suggests that the DL approach could possibly provide a noninvasive means for the optimization of chemotherapy.

Pancreatic cancer - the past, the present, and the future

BACKGROUND

Pancreatic cancer has been and still is associated with a very poor prognosis. This is due to a lack of major breakthroughs with respect to early diagnosis, prognostication, prediction, as well as novel, targeted therapies. The benefits of surgery and chemotherapy are evident, but the fact that only some 10% of all patients have early, localized disease highlights the unmet need for new early detection methods. An improved understanding of tumor biology and the development of molecular markers detectable both in the circulation and in cancer tissues may underlie the development of new tools for optimizing both diagnosis and treatment.

MATERIAL AND METHODS

Review of the literature.

RESULTS AND CONCLUSION

If we do not improve precision oncology for pancreatic ductal adenocarcinoma, the prognosis will still remain dismal and the" burden" on society will increase substantially.

Single Cell RNA Sequencing: A New Frontier in Pancreatic Ductal Adenocarcinoma

Simple Summary

Pancreatic cancer has a very low survival rate for several reasons. One of those is primarily due to the difficulty in diagnosing it at an early stage. For this reason, it is important to refine our understanding of this disease to guide the development of new diagnostic and therapeutic modalities to combat this fatal illness. Here we attempt to provide a review of current progress in utilizing single-cell RNA sequencing (scRNA-seq) techniques in the molecular profiling of pancreatic ductal adenocarcinoma.

Abstract

Pancreatic ductal adenocarcinoma is a malignancy with a high mortality rate. It exhibits significant heterogeneity in metabolic pathways which are associated with its progression. In this review, we discuss the role of single cell RNA sequencing in unraveling the metabolic and clinical features of these highly malignant tumors.

Diagnostic Accuracy of CT for Evaluating Circumferential Resection Margin Status in Resectable or Borderline Resectable Pancreatic Head Cancer: A Prospective Study Using Axially Sliced Surgical Pathologic Correlation

OBJECTIVE

CT plays a central role in determining the resectability of pancreatic cancer, which directs the use of neoadjuvant therapy. This study aimed to assess the diagnostic accuracy of CT in predicting circumferential resection margin (CRM) involvement in patients with resectable or borderline resectable pancreatic head cancer.

MATERIALS AND METHODS

Seventy-seven patients who were scheduled for upfront surgery for resectable or borderline resectable pancreatic head cancer were prospectively enrolled, and 75 patients (38 male and 37 female; mean age ± standard deviation, 68 ± 11 years) were finally analyzed. The CRM status was evaluated separately for the superior mesenteric artery (SMA) and posterior and superior mesenteric vein/portal vein (SMV/PV) margins. Three independent radiologists reviewed the preoperative CT images and evaluated the resection margin status. The reference standard for CRM status was pathologic examination of pancreaticoduodenectomy specimens in an axial plane perpendicular to the axis of the second portion of the duodenum. The diagnostic accuracy of CT was assessed for overall CRM involvement, defined as involvement of the SMA or posterior margins (per-patient analysis), and involvement of each of the three resection margins (per-margin analysis). The data were pooled using a crossed random effects model.

RESULTS

Forty patients had pathologically confirmed overall CRM involvement in pancreatic cancer, while CRM involvement was not seen in 35 patients. For overall CRM involvement, the pooled sensitivity and specificity were 15% (95% confidence interval: 7%-49%) and 99% (96%-100%), respectively. For each of the resection margins, the pooled sensitivity and specificity were 14% (9%-54%) and 99% (38%-100%) for the SMA margin, 12% (8%-46%) and 99% (97%-100%) for the posterior margin; and 37% (29%-53%) and 96% (31%-100%) for the SMV/PV margin, respectively.

CONCLUSION

CT showed very high specificity but low sensitivity in predicting pathological CRM involvement in pancreatic cancer.

Response to Neoadjuvant Therapy and Prognosis in Patients with Resectable Pancreatic Cancer: A Propensity Score Matching Analysis

Background/Aims

Controversy regarding the effectiveness of neoadjuvant therapy for resectable pancreatic ductal adenocarcinoma (PDAC) still exists. Here, we aimed to identify the potential benefits of neoadjuvant therapy followed by surgery for resectable PDAC.

Methods

We reviewed radiologically resectable PDAC patients who received resection with curative intent at a tertiary hospital in South Korea between January 2012 and August 2019. A total of 202 patients underwent curative resection for resectable PDAC 167 underwent surgical resection first during this period, and 35 received neoadjuvant chemotherapy/chemoradiation therapy followed by surgery. Resectable PDAC patients were subdivided, and 13 propensity score matching (PSM) was performed to reduce selection bias.

Results

Compared with the group that received surgery first, the group that received neoadjuvant treatment followed by surgery had significantly smaller tumors (22.0 mm vs 27.0 mm, p=0.004), a smaller proportion of patients with postoperative pathologic T stage (p=0.026), a smaller proportion of patients with lymphovascular invasion (20.0% vs 40.7%, p=0.022), and a larger proportion of patients with negative resection margins (74.3% vs 51.5%, p=0.049). After PSM, the group that received neoadjuvant therapy had a significantly longer progression-free survival than those in the group that underwent surgery first (29.6 months vs 15.1 months, p=0.002). Overall survival was not significantly different between the two groups after PSM analysis.

Conclusions

We observed significantly better surgical outcomes and progression-free survival with the addition of neoadjuvant therapy to the management of resectable PDAC. However, despite PSM, there was still selection bias due to the use of different regimens between the groups receiving surgery first and neoadjuvant therapy. Large homogeneous samples are needed in the future prospective studies.

A Patient With Locally Advanced Mismatch-Repair-Deficient Pancreatic Ductal Adenocarcinoma Successfully Treated With Neoadjuvant Immunotherapy

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive malignancy with a dismal prognosis. Approximately 30% of patients present with locally advanced disease, defined as pancreatic tumor with invasion to adjacent structures, including the vasculatures that preclude an upfront surgical resection. Emerging data suggest that neoadjuvant therapy, typically consisting of systemic chemotherapy followed by concurrent chemoradiation, increases the likelihood of potentially curative R0 resection by downstaging the tumor and improves survival in patients with locally advanced PDAC. PDAC with deficient DNA mismatch repair (dMMR)/microsatellite instability-high molecular signature is exceedingly rare. The role of immunotherapy is emerging in various dMMR gastrointestinal tumors, both in the metastatic and neoadjuvant settings. However, the efficacy of immunotherapy in the neoadjuvant setting in patients with dMMR locally advanced PDAC remains unknown. Herein, we describe a patient who presented with unresectable dMMR locally advanced PDAC and underwent neoadjuvant immunotherapy with pembrolizumab that resulted in a remarkable reduction of the tumor size, rendering the tumor resectable. Furthermore, the presence of dMMR signature in the tumor was detected by circulating tumor DNA analysis. This is the first report, to our knowledge, of the successful use of neoadjuvant immunotherapy in a patient with locally advanced PDAC.

Neoadjuvant therapy versus upfront surgery for early-stage left-sided pancreatic adenocarcinoma: A propensity-matched analysis from a national cohort of distal pancreatectomies

BACKGROUND

There are limited data on the efficacy of neoadjuvant therapy (NAT) for early-stage distal pancreas adenocarcinoma (PDAC). Previous studies focused on adenocarcinoma of the head of the pancreas or dealt with borderline and locally advanced tumors of the body and tail.

METHODS

This is a retrospective study of the National Cancer Database between 2006 and 2015. A propensity-matched analysis was performed to compare overall survival estimates between NAT and upfront resection (UR) groups.

RESULTS

A total of 5003 distal pancreatectomies for PDAC were identified, of whom 408 (9%) received NAT. After 1:1 matching, 353 NAT patients were compared with 353 UR patients. NAT was associated with lower 90-day mortality. There were no differences in the number of lymph nodes retrieved, or length of stay. With matching, the NAT group had higher median overall survival compared with UR (33.0 vs. 27.0 months; p = 0.009) and adjusted overall survival (hazard ratio = 0.63, 95% confidence interval = 0.51-0.77; p < 0.001).

CONCLUSION

The receipt of NAT followed by distal pancreatectomy for early-stage distal PDAC is associated with improved overall survival compared with UR. This study supports the use of NAT in the multimodal therapy paradigm of early-stage adenocarcinoma of the body and tail of the pancreas.