Improved Assessment of Response Status in Patients with Pancreatic Cancer Treated with Neoadjuvant Therapy using Somatic Mutations and Liquid Biopsy Analysis

Building on the clinical applicability of ctDNA analysis in non-metastatic pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma represents one of the solid tumors showing the worst prognosis worldwide, with a high recurrence rate after adjuvant or neoadjuvant therapy. Circulating tumor DNA analysis raised as a promising non-invasive tool to characterize tumor genomics and to assess treatment response. In this study, surgical tumor tissue and sequential blood samples were analyzed by next-generation sequencing and were correlated with clinical and pathological characteristics. Thirty resectable/borderline pancreatic ductal adenocarcinoma patients treated at the Hospital Universitario de Navarra were included. Circulating tumoral DNA sequencing identified pathogenic variants in KRAS and TP53, and in other cancer-associated genes. Pathogenic variants at diagnosis were detected in patients with a poorer outcome, and were correlated with response to neoadjuvant therapy in borderline pancreatic ductal adneocarcinoma patients. Higher variant allele frequency at diagnosis was associated with worse prognosis, and thesum of variant allele frequency was greater in samples at progression. Our results build on the potential value of circulating tumor DNA for non-metastatic pancreatic ductal adenocarcinoma patients, by complementing tissue genetic information and as a non-invasive tool for treatment decision. Confirmatory studies are needed to corroborate these findings.

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.

Neoadjuvant treatment of pancreatic ductal adenocarcinoma: Whom, when and how

Pancreatic ductal adenocarcinoma (PDAC), which is notorious for its aggressiveness and poor prognosis, remains an area of great unmet medical need, with a 5-year survival rate of 10% - the lowest of all solid tumours. At diagnosis, only 20% of patients have resectable pancreatic cancer (RPC) or borderline RPC (BRPC) disease, while 80% of patients have unresectable tumours that are locally advanced pancreatic cancer (LAPC) or have distant metastases. Nearly 60% of patients who undergo upfront surgery for RPC are unable to receive adequate adjuvant chemotherapy (CHT) because of postoperative complications and early cancer recurrence. An important paradigm shift to achieve better outcomes has been the sequence of therapy, with neoadjuvant CHT preceding surgery. Three surgical stages have emerged for the preoperative assessment of nonmetastatic pancreatic cancers: RPC, BRPC, and LAPC. The main goal of neoadjuvant treatment (NAT) is to improve postoperative outcomes through enhanced selection of candidates for curative-intent surgery by identifying patients with aggressive or metastatic disease during initial CHT, reducing tumour volume before surgery to improve the rate of margin-negative resection (R0 resection, a microscopic margin-negative resection), reducing the rate of positive lymph node occurrence at surgery, providing early treatment of occult micrometastatic disease, and assessing tumour chemosensitivity and tolerance to treatment as potential surgical criteria. In this editorial, we summarize evidence concerning NAT of PDAC, providing insights into future practice and study design. Future research is needed to establish predictive biomarkers, measures of therapeutic response, and multidisciplinary strategies to improve patient-centered outcomes.

Circulating tumor cells as prognostic marker in pancreatic cancer

In this editorial we comment on the article by Zhang et al published in the recent issue of the World Journal of Clinical Oncology. Pancreatic cancer is the fourth most common cause of cancer-related mortality and has the lowest survival rate among all solid cancers. It causes 227000 deaths annually worldwide, and the 5-year survival rate is very low due to early metastasis, which is 4.6%. Cancer survival increases with better knowledge of risk factors and early and accurate diagnosis. Circulating tumor cells (CTCs) are tumor cells that intravasate from the primary tumor or metastasis foci into the peripheral blood circulation system spontaneously or during surgical operations. Detection of CTC in blood is promising for early diagnosis. In addition, studies have associated high CTC levels with a more advanced stage, and more intensive treatments should be considered in cases with high CTC. In tumors that are considered radiologically resectable, it may be of critical importance in detecting occult metastases and preventing unnecessary surgeries.

In Neoadjuvant FOLFIRINOX Chemotherapy for Pancreatic Ductal Adenocarcinoma, Which Response is the More Reliable Indicator for Prognosis, Radiologic or Biochemical?

BACKGROUND

In this era of increasing neoadjuvant chemotherapy, methods for evaluating responses to neoadjuvant chemotherapy are still diverse among institutions. Additionally, the efficacy of adjuvant chemotherapy for patients undergoing neoadjuvant chemotherapy remains unclear. Therefore, this retrospective study was performed to evaluate the effectiveness of methods for assessing response to neoadjuvant chemotherapy and the need for adjuvant chemotherapy in treating patients with non-metastatic pancreatic ductal adenocarcinoma.

METHODS

The study identified 150 patients who underwent neoadjuvant FOLFIRINOX chemotherapy followed by curative-intent pancreatectomy. The patients were stratified by biochemical response based on the normalization of carbohydrate antigen 19-9 and by radiologic response based on size change at imaging.

RESULTS

The patients were classified into the following three groups based on their response to neoadjuvant chemotherapy and prognosis: biochemical responders (BR+), radiology-only responders (BR-/RR+), and non-responders (BR-/RR-). The 3-year overall survival rate was higher for BR+ (71.0%) than for BR-/RR+ (53.6%) or BR-/RR- (33.1%) (P < 0.001). Response to neoadjuvant chemotherapy also was identified as a significant risk factor for recurrence in a comparison between BR-/RR+ and BR+ (hazard ratio [HR], 2.15; 95% confidence interval [CI] 1.19-3.88; P = 0.011) and BR-/RR- (HR, 3.82; 95% CI 2.41-6.08; P < 0.001). Additionally, regardless of the response to neoadjuvant chemotherapy, patients who completed adjuvant chemotherapy had a significantly higher 3-year overall survival rate than those who did not.

CONCLUSIONS

This response evaluation criterion for neoadjuvant chemotherapy is feasible and can significantly predict prognosis. Additionally, completion of adjuvant chemotherapy could be helpful to patients who undergo neoadjuvant chemotherapy regardless of their response to neoadjuvant chemotherapy.

Clinical Application of Liquid Biopsy in Pancreatic Cancer: A Narrative Review

Pancreatic ductal adenocarcinoma contributes significantly to global cancer-related deaths, featuring only a 10% survival rate over five years. The quest for novel tumor markers is critical to facilitate early diagnosis and tailor treatment strategies for this disease, which is key to improving patient outcomes. In pancreatic ductal adenocarcinoma, these markers have been demonstrated to play a crucial role in early identification, continuous monitoring, and prediction of its prognosis and have led to better patient outcomes. Nowadays, biopsy specimens serve to ascertain diagnosis and determine tumor type. However, liquid biopsies present distinct advantages over conventional biopsy techniques. They offer a noninvasive, easily administered procedure, delivering insights into the tumor's status and facilitating real-time monitoring. Liquid biopsies encompass a variety of elements, such as circulating tumor cells, circulating tumor DNA, extracellular vesicles, microRNAs, circulating RNA, tumor platelets, and tumor endothelial cells. This review aims to provide an overview of the clinical applications of liquid biopsy as a technique in the management of pancreatic cancer.

Survival benefit and impact of adjuvant chemotherapy following systemic neoadjuvant chemotherapy in patients with resected pancreas ductal adenocarcinoma: a retrospective cohort study

BACKGROUND

Patients with pancreatic ductal adenocarcinoma (PDAC) are increasingly receiving systemic neoadjuvant chemotherapy (NAC), particularly those with borderline resectable and locally advanced disease. However, the specific role of additional adjuvant chemotherapy (AC) in these patients is unknown. The objective of this study is to further assess the clinical benefit and impact of systemic AC in patients with resected PDAC after NAC.

METHODS

Data on PDAC patients with or without AC following systemic NAC and surgical resection were retrospectively retrieved from the Surveillance, Epidemiology, and End Results (SEER) database between 2006 and 2019. A matched cohort was created using propensity score matching (PSM), and baseline characteristics were balanced to reduce bias. Overall survival (OS) and cancer-specific survival (CSS) were calculated using matching cohorts.

RESULTS

The study enrolled a total of 1589 patients, with 623 (39.2%) in the AC group and 966 (51.8%) in the non-AC group [mean age, 64.0 (9.9) years; 766 (48.2%) were females and 823 (51.8%) were males]. All patients received NAC, and among the crude population, 582 (36.6%) received neoadjuvant radiotherapy, while 168 (10.6%) received adjuvant radiotherapy. Following the 1:1 PSM, 597 patients from each group were evaluated further. The AC and non-AC groups had significantly different median OS (30.0 vs. 25.0 months, P =0.002) and CSS (33.0 vs. 27.0 months, P =0.004). After multivariate Cox regression analysis, systemic AC was independently associated with improved survival ( P =0.003, HR=0.782; 95% CI, 0.667-0.917 for OS; P =0.004, HR=0.784; 95% CI, 0.663-0.926 for CSS), and age, tumor grade, and AJCC N staging were also independent predictors of survival. Only patients younger than 65 years old and those with a pathological N1 category showed a significant association between systemic AC and improved survival in the subgroup analysis adjusted for these covariates.

CONCLUSION

Systemic AC provides a significant survival benefit in patients with resected PDAC following NAC compared to non-AC patients. Our study discovered that younger patients, patients with aggressive tumors and potentially well response to NAC might benefit from AC to achieve prolonged survival after curative tumor resection.

Selection of patients with pancreatic adenocarcinoma who may benefit from radiotherapy

Despite combination chemotherapy demonstrating a positive effect on survival, the clinical outcomes of pancreatic adenocarcinoma (PDAC) remain poor. Radiotherapy was previously a component of the curative treatment of PDAC. Advances in imaging and computer sciences have enabled the prescription of higher dosage of radiation focused on tumours with minimal toxicity to normal tissue. However, the role of radiotherapy has not been established in the curative treatment of localized PDAC because of the conflicting results from large prospective trials. Most studies have demonstrated improved locoregional control but no survival benefit from additional chemoradiotherapy (CRT) in addition to chemotherapy for resectable, borderline or locally advanced PDAC. The improved locoregional control enabled by CRT does not cause extended survival because of rapid distant progression in a significant proportion of patients with PDAC. Several single-institute studies of prescribing intensive chemotherapy with modern ablative radiotherapy for locally advanced PDAC have demonstrated extended survival with an acceptable safety profile. In an analysis after long-term follow-up, the PREOPANC study demonstrated a survival benefit from neoadjuvant gemcitabine-based CRT in resected PDAC relative to upfront surgery followed by adjuvant gemcitabine only. These observations indicated that the role of radiotherapy in PDAC should be evaluated in a subgroup of patients without rapid distant progression because systemic therapy for PDAC remains underdeveloped. We reviewed critical imaging, tissue, liquid and clinical biomarkers to differentiate the heterogeneous biologic spectra of patients with PDAC to identify those who may benefit the most from local radiotherapy. Exclusion of patients with localised PDAC who develop distant progression in a short time and undergo extended upfront chemotherapy for over 4 months may enable the identification of a survival benefit of local radiotherapy. Though promising, the effectiveness of biomarkers must be validated in a multi-institutional prospective study of patients with PDAC receiving CRT or not receiving CRT.

Preoperative treatments in borderline resectable and locally advanced pancreatic cancer: current evidence and new perspectives

Surgery is the only curative treatment for non-metastatic pancreatic adenocarcinoma, but less than 20% of patients present a resectable disease at diagnosis. Treatment strategies and disease definition for borderline resectable pancreatic cancer (BRPC) and locally advanced pancreatic cancer (LAPC) vary in the different cancer centres. Preoperative chemotherapy (CT) is the standard of care for both BRPC and LAPC patients, however literature data are still controversial concerning the type, dose and duration of the different CT regimens, as well as regarding the integration of radiotherapy (RT) or chemoradiation (CRT) in the therapeutic algorithm. In this unsettled debate, we aimed at focusing on the therapeutic regimens currently in use and relative literature data, to report international trials comparing the available therapeutic options or explore the introduction of new pharmacological agents, and to analyse possible new scenarios in microenvironment evaluation before and after neoadjuvant therapies or in patients' selection at a molecular level.

Tailoring Adjuvant Chemotherapy to Biologic Response Following Neoadjuvant Chemotherapy Impacts Overall Survival in Pancreatic Cancer

BACKGROUND

The role of postoperative chemotherapy in patients with resected pancreatic cancer who receive neoadjuvant treatment is unknown. Clinicians use changes in CA19-9 and histopathologic scores to assess treatment response. We sought to investigate if CA19-9 normalization in response to NAT can help guide the need for postoperative treatment.

METHODS

Patients with elevated baseline CA19-9 (CA19-9 > 37U/mL) who received NAT followed by surgery between 2011 and 2019 were retrospectively reviewed. Treatment response was determined by CA19-9 normalization following NAT and histopathologic scoring. The role of postoperative chemotherapy was analyzed in light of CA19-9 normalization and histopathologic response.

RESULTS

We identified and included 345 patients. Following NAT, CA19-9 normalization was observed in 125 patients (36.2%). CA19-9 normalization was associated with a favorable histopathologic response (41.6% vs 23.2%, p < 0.001) and a lower ypT (p < 0.001) and ypN stage (p = 0.003). Receipt of adjuvant chemotherapy was associated with improved overall survival in patients in whom CA19-9 did not normalize following NAT (26.8 vs 16.4 months, p = 0.008). In patients who received 5FU-based NAT and in whom CA19-9 did not normalize, receipt of 5FU-based adjuvant chemotherapy was associated with improved OS (p = 0.014).

CONCLUSION

CA19-9 normalization in response to NAT was associated with favorable outcomes and can serve as a biomarker for treatment response. In patients where CA19-9 did not normalize, receipt of postoperative chemotherapy was associated with improved OS. These patients also benefited from additional 5FU-based postoperative chemotherapy following 5FU-based NAT.

Circulating tumor DNA in molecular assessment feasibly predicts early progression of pancreatic cancer that cannot be identified via initial imaging

Molecular assessment using circulating tumor DNA (ctDNA) has not been well-defined. We recruited 61 pancreatic cancer (PC) patients who underwent initial computed tomography (CT) imaging study during first-line chemotherapy. Initial molecular assessment was performed using droplet digital PCR and defined as the change in KRAS-mutated ctDNA before and after treatments, which was classified into five categories: mNT, molecular negative; mCR, complete response; mPR, partial response; mSD, stable disease; mPD, progressive disease. Of 61 patients, 14 diagnosed with PD after initial CT imaging showed significantly worse therapeutic outcomes than 47 patients with disease control. In these 47 patients, initial molecular assessment exhibited significant differences in therapeutic outcomes between patients with and without ctDNA (mPD + mSD vs. mCR + mNT; 13.2 M vs. 21.7 M, P = 0.0029) but no difference between those with mPD and mSD + mCR + mNT, suggesting that the presence of ctDNA had more impact on the therapeutic outcomes than change in its number. Multivariate analysis revealed that it was the only independent prognostic factor (P = 0.0405). The presence of ctDNA in initial molecular assessment predicted early tumor progression and identified PC patients more likely to benefit from chemotherapy.

Neoadjuvant therapy for pancreatic cancer

Patients with localized pancreatic ductal adenocarcinoma (PDAC) are best treated with surgical resection of the primary tumour and systemic chemotherapy, which provides considerably longer overall survival (OS) durations than either modality alone. Regardless, most patients will have disease relapse owing to micrometastatic disease. Although currently a matter of some debate, considerable research interest has been focused on the role of neoadjuvant therapy for all forms of resectable PDAC. Whilst adjuvant combination chemotherapy remains the standard of care for patients with resectable PDAC, neoadjuvant chemotherapy seems to improve OS without necessarily increasing the resection rate in those with borderline-resectable disease. Furthermore, around 20% of patients with unresectable non-metastatic PDAC might undergo resection following 4-6 months of induction combination chemotherapy with or without radiotherapy, even in the absence of a clear radiological response, leading to improved OS outcomes in this group. Distinct molecular and biological responses to different types of therapies need to be better understood in order to enable the optimal sequencing of specific treatment modalities to further improve OS. In this Review, we describe current treatment strategies for the various clinical stages of PDAC and discuss developments that are likely to determine the optimal sequence of multimodality therapies by integrating the fundamental clinical and molecular features of the cancer.

A Paradigm Shifts: Neoadjuvant Therapy for Clearly Resectable Pancreatic Cancer

Over the past decade, neoadjuvant therapy has become the standard of care for patients with borderline resectable and locally advanced pancreatic cancer. The surgical community remains divided regarding the value of neoadjuvant therapy for patients who present with clearly resectable disease. Thus far, randomized controlled trials comparing neoadjuvant therapy with conventional upfront surgical strategies for patients with clearly resectable pancreatic cancer have been plagued by poor accrual, and are often underpowered. Nonetheless, meta-analyses of the results of these trials suggest that neoadjuvant therapy can be offered as an acceptable standard of care for patients with clearly resectable pancreatic cancer. Previous trials used neoadjuvant gemcitabine, but more recent studies have demonstrated superior survival for patients who were able to tolerate neoadjuvant FOLFIRINOX (leucovorin, 5-fluorouracil, irinotecan hydrochloride, and oxaliplatin). The increased utilization of FOLFIRINOX may be shifting the treatment paradigm in favor of neoadjuvant therapy among patients with clearly resectable disease. Randomized controlled trials assessing the value of neoadjuvant FOLFIRINOX in clearly resectable pancreatic cancer, which are expected to provide more conclusive recommendations, are still ongoing. This review outlines the rationale, considerations, and current level of evidence for the use of neoadjuvant therapy in patients with clearly resectable pancreatic cancer.

Technical options in surgery for artery-involving pancreatic cancer: Invasion depth matters

Background

The artery involvement explains the majority of primary unresectability of non-metastatic pancreatic cancer patients and both arterial resection and artery-sparing dissection techniques are utilized in curative-intent pancreatectomies for artery-involving pancreatic cancer (ai-PC) patients.

Methods

This narrative review summarized the history of resectability evaluation for ai-PC and attempted to interpret its current pitfalls that led to the divergence of resectability prediction and surgical exploration, with a focus on the rationale and the surgical outcomes of the sub-adventitial divestment technique.

Results

The circumferential involvement of artery by tumor currently defined the resectability of ai-PC but insufficient to preclude laparotomy with curative intent. The reasons behind could be: 1. The radiographic involvement of tumor to arterial circumference was not necessarily resulted in histopathological artery wall invasion; 2. the developed surgical techniques facilitated radical resection, better perioperative safety as well as oncological benefit. The feasibility of periadventitial dissection, sub-adventitial divestment and other artery-sparing techniques for ai-PC depended on the tumor invasion depth to the artery, i.e., whether the external elastic lamina (EEL) was invaded demonstrating a hallmark plane for sub-adventitial dissections. These techniques were reported to be complicated with preferable surgical outcomes comparing to arterial resection combined pancreatectomies, while the arterial resection combined pancreatectomies were considered performed in patients with more advanced disease.

Conclusions

Adequate preoperative imaging modalities with which to evaluate the tumor invasion depth to the artery are to be developed. Survival benefits after these techniques remain to be proven, with more and higher-level clinical evidence needed.

Key message

The current resectability evaluation criteria, which were based on radiographic circumferential involvement of the artery by tumor, was insufficient to preclude curative-intent pancreatectomies for artery-involving pancreatic cancer patients. With oncological benefit to be further proven, periarterial dissection and arterial resection have different but overlapping indications, and predicting the tumor invasion depth in major arteries was critical for surgical planning.

Analysis of Risk Factors for Distant Metastasis of Pancreatic Ductal Adenocarcinoma without Regional Lymph Node Metastasis and a Nomogram Prediction Model for Survival

Background

Negative regional lymph nodes do not indicate a lack of distant metastasis. A considerable number of patients with negative regional lymph node pancreatic cancer will skip the step of regional lymph node metastasis and directly develop distant metastasis.

Methods

We retrospectively analyzed the clinicopathological characteristics of patients with negative regional lymph node pancreatic cancer and distant metastasis in the Surveillance, Epidemiology, and End Results database from 2010 to 2015. Multivariate logistic analysis and Cox analysis were used to determine the independent risk factors that promoted distant metastasis and the 1-, 2-, and 3-year cancer-specific survival in this subgroup.

Results

Sex, age, pathological grade, surgery, radiotherapy, race, tumor location, and tumor size were significantly correlated with distant metastasis (P < 0.05). Among these factors, pathological grade II and above, tumor site other than the pancreatic head, and tumor size >40 mm were independent risk factors for distant metastasis; age ≥60 years, tumor size ≤21 mm, surgery, and radiation were protective factors against distant metastasis. Age, pathological grade, surgery, chemotherapy, and metastasis site were identified as predictors of survival. Among them, age ≥40 years, pathological grade II and above, and multiple distant metastasis were considered independent risk factors for cancer-specific survival. Surgery and chemotherapy were considered protective factors for cancer-specific survival. The prediction performance of the nomogram was significantly better than that of the traditional American Joint Committee on Cancer tumor, node, metastasis staging system. We also established an online dynamic nomogram calculator, which can predict the survival rate of patients at different follow-up time points.

Conclusion

Pathological grade, tumor location, and tumor size were independent risk factors for distant metastasis in pancreatic ductal adenocarcinoma with negative regional lymph nodes. Older age, smaller tumor size, surgery, and radiotherapy were protective factors against distant metastasis. A new nomogram that was constructed could effectively predict cancer-specific survival in pancreatic ductal adenocarcinoma with negative regional lymph nodes and distant metastasis. Furthermore, an online dynamic nomogram calculator was established.

Targeted therapy for pancreatic ductal adenocarcinoma: Mechanisms and clinical study

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive and lethal malignancy with a high rate of recurrence and a dismal 5-year survival rate. Contributing to the poor prognosis of PDAC is the lack of early detection, a complex network of signaling pathways and molecular mechanisms, a dense and desmoplastic stroma, and an immunosuppressive tumor microenvironment. A recent shift toward a neoadjuvant approach to treating PDAC has been sparked by the numerous benefits neoadjuvant therapy (NAT) has to offer compared with upfront surgery. However, certain aspects of NAT against PDAC, including the optimal regimen, the use of radiotherapy, and the selection of patients that would benefit from NAT, have yet to be fully elucidated. This review describes the major signaling pathways and molecular mechanisms involved in PDAC initiation and progression in addition to the immunosuppressive tumor microenvironment of PDAC. We then review current guidelines, ongoing research, and future research directions on the use of NAT based on randomized clinical trials and other studies. Finally, the current use of and research regarding targeted therapy for PDAC are examined. This review bridges the molecular understanding of PDAC with its clinical significance, development of novel therapies, and shifting directions in treatment paradigm.

Cancer-cell-derived sialylated IgG as a novel biomarker for predicting poor pathological response to neoadjuvant therapy and prognosis in pancreatic cancer

BACKGROUND

Neoadjuvant therapy (NAT) is increasingly applied in pancreatic ductal adenocarcinoma (PDAC); however, accurate prediction of therapeutic response to NAT remains a pressing clinical challenge. Cancer-cell-derived sialylated immunoglobulin G (SIA-IgG) was previously identified as a prognostic biomarker in PDAC. This study aims to explore whether SIA-IgG expression in treatment-naïve fine needle aspirate (FNA) biopsy specimens could predict the pathological response (PR) to NAT for PDAC.

METHODS

Endoscopic ultrasonography-guided FNA biopsy specimens prior to NAT were prospectively obtained from 72 patients with PDAC at the Johns Hopkins Hospital. SIA-IgG expression of PDAC specimens was assessed by immunohistochemistry. Associations between SIA-IgG expression and PR, as well as patient prognosis, were analyzed. A second cohort enrolling surgically resected primary tumor specimens from 79 patients with PDAC was used to validate the prognostic value of SIA-IgG expression.

RESULTS

SIA-IgG was expressed in 58.3% of treatment-naïve FNA biopsies. Positive SIA-IgG expression at diagnosis was associated with unfavorable PR and can serve as an independent predictor of PR. The sensitivity and specificity of SIA-IgG expression in FNA specimens in predicting an unfavorable PR were 63.9% and 80.6%, respectively. Both positive SIA-IgG expression in treatment-naïve FNA specimens and high SIA-IgG expression in surgically resected primary tumor specimens were significantly associated with shorter survival.

CONCLUSIONS

Assessment of SIA-IgG on FNA specimens prior to NAT may help predict PR for PDAC. Additionally, SIA-IgG expression in treatment-naïve FNA specimens and surgically resected primary tumor specimens were predictive of the prognosis for PDAC.

Correlation of GDFT combined with rehabilitation therapy in DNA damage repair of esophageal cancer cells

Esophageal cancer is a common malignant tumor with a high incidence and a serious threat to human health. The treatment of esophageal cancer is a complex process, which requires the comprehensive use of a variety of treatment methods. At present, the treatment of esophageal cancer mainly includes surgery, radiotherapy, chemotherapy and immunotherapy. The research on the treatment of cancer cells based on Goal directed fluid therapy (GDFT) combined with rehabilitation therapy is the focus of the current society. This paper proposed a study on DNA damage repair of cancer cells based on goal directed fluid therapy combined with rehabilitation therapy, aiming to optimize the traditional treatment of esophageal cancer by using goal directed fluid therapy technology. The algorithm proposed in this paper was an electroencephalogram (EEG) signal optimization algorithm based on combined rehabilitation therapy. Through this algorithm, the electroencephalogram signal could be optimized. The algorithm could speed up signal processing, and improve signal reliability and stability by reducing the influence of interference signals and improving the signal to noise ratio. These optimization measures could better help researchers analyze and understand electroencephalogram signals, so as to help better study brain functions and diseases. Through the test and investigation on the treatment of cancer cells based on goal directed fluid therapy combined with rehabilitation therapy, the results showed that the blood transfusion volume of goal directed fluid therapy treatment and conventional treatment was 251.5 mL and 288.3 mL respectively. This showed that after goal directed fluid therapy treatment, the input amount of various medical fluids was relatively reduced, and the use of medical fluids was more economical. In addition, their bleeding volumes were 295.2 mL and 324.4 mL, respectively. Urine volume was 382.3 mL and 418.1 mL respectively. This showed that after goal directed fluid therapy treatment, the patient's blood loss and urine volume were relatively reduced, which has improved the patient's health. This experiment has proved the excellent ability of goal directed fluid therapy combined with rehabilitation therapy in the treatment of esophageal cancer, and this research result has also proved the excellent medical effect of goal directed fluid therapy technology. Similarly, this paper also provided valuable reference information for the treatment of esophageal cancer.

Liquid biopsy leads to a paradigm shift in the treatment of pancreatic cancer

Pancreatic ductal adenocarcinoma (PDAC) is one of the most cancers. Its 5-year survival rate is very low. The recent induction of neoadjuvant chemotherapy and improvements in chemotherapy for patients with pancreatic cancer have resulted in improved survival outcomes. However, the prognosis of pancreatic cancer is still poor. To dramatically improve the prognosis, we need to develop more tools for early diagnosis, treatment selection, disease monitoring, and response rate evaluation. Recently, liquid biopsy (circulating free DNA, circulating tumor DNA, circulating tumor cells, exosomes, and microRNAs) has caught the attention of many researchers as a new biomarker that is minimally invasive, confers low-risk, and displays an overall state of the tumor. Thus, liquid biopsy does not employ the traditional difficulties of obtaining tumor samples from patients with advanced PDAC to investigate their molecular biological status. In addition, it allows for long-term monitoring of the molecular profile of tumor progression. These could help in identifying tumor-specific alterations that use the target structure for tailor-made therapy. Through this review, we highlighted the latest discoveries and advances in liquid biopsy technology in pancreatic cancer research and showed how it can be applied in clinical practice.

The Value of Circulating Tumor Cells in the Prognosis and Treatment of Pancreatic Cancer

In the past few decades, tumor diagnosis and treatment theory have developed in a variety of directions. The number of people dying from pancreatic cancer increases while the mortality rate of other common tumors decreases. Traditional imaging methods show the boundaries of pancreatic tumor, but they are not sufficient to judge early micrometastasis. Although carcinoembryonic antigen (CEA) and carbohydrate antigen19-9 (CA19-9) have the obvious advantages of simplicity and minimal invasiveness, these biomarkers obviously lack sensitivity and specificity. Circulating tumor cells (CTCs) have attracted attention as a non-invasive, dynamic, and real-time liquid biopsy technique for analyzing tumor characteristics. With the continuous development of new CTCs enrichment technologies, substantial progress has been made in the basic research of CTCs clinical application prospects. In many metastatic cancers, CTCs have been studied as an independent prognostic factor. This article reviews the research progress of CTCs in the treatment and prognosis of pancreatic cancer.

Current status and future perspectives of clinical research in pancreatic cancer: Establishment of evidence by science

Pancreatic cancer is one of the most aggressive diseases in the world due to a lack of early detection, leading to an overall 5-year survival of only 10%. In recent years, clinical trials targeted pancreatic cancer in efforts to improve survival. These studies introduce new technologies, concepts, and evidence which have instilled new optimism for improving prognosis. This review summarizes the current status of the recent (5-year) clinical trials and describes contemporary research on pancreatic cancer, including surgical technology, diagnostic skills, traditional chemoradiotherapy, neoadjuvant chemotherapy, immunotherapy, targeted therapy, and precision medicine. Then, the future trend and direction of clinical trials on pancreatic cancer are discussed.

Radiation therapy in borderline resectable pancreatic cancer: A review

BACKGROUND

Borderline resectable pancreatic cancer constitutes a complex clinical entity, presenting the clinician with a locally aggressive disease that has a proclivity for distant spread. The benefits of radiation therapy, such as improved local control and improved survival, have been questioned. In this review we seek to summarize the existing evidence on radiation therapy in borderline resectable pancreatic cancer and highlight future areas of research.

METHODS

A comprehensive review of PubMed for clinical studies reporting outcomes in borderline resectable pancreatic cancer was performed in June 2021, with an emphasis placed on prospective studies.

RESULTS

Radiologic "downstaging" in borderline resectable pancreatic cancer is a rare event, although some evidence shows increased clinical response to neoadjuvant chemotherapy over radiation therapy. Margin status seems to be equivalent between regimens that use neoadjuvant chemotherapy alone and regimens that include neoadjuvant radiation therapy. Local control in borderline resectable pancreatic cancer is likely improved with radiation therapy; however, the benefit of improved local control in a disease marked by systemic failure has been questioned. Although some studies have shown improved survival with radiation therapy, differences in the delivery and tolerance of chemotherapy between the neoadjuvant and adjuvant setting confound these results. When the evidence is evaluated as a whole, there is no clear survival benefit of radiation therapy in borderline resectable pancreatic cancer.

CONCLUSION

Once considered a staple of therapy, the role of radiation therapy in borderline resectable pancreatic cancer is evolving as systemic therapy regimens continues to improve. Increased clinical understanding of disease phenotype and response are needed to accurately tailor therapy for individual patients and to improve outcomes in this complex patient population.

Association of Matrix Metalloproteinase 7 Expression With Pathologic Response After Neoadjuvant Treatment in Patients With Resected Pancreatic Ductal Adenocarcinoma

Importance

The use of neoadjuvant therapy (NAT) in resectable pancreatic ductal adenocarcinoma (PDAC) remains controversial. A favorable pathologic response (complete or marked tumor regression) to NAT is associated with better outcomes in patients with resected PDAC. The role of NAT for early systemic control compared with immediate surgical resection for PDAC is under investigation. In the era of precision medicine, biomarkers for patient selection and prediction of therapy response are crucial.

Objective

To evaluate the use of assessment for protein expression on fine-needle aspiration (FNA) biopsy specimens in predicting pathologic response to NAT in treatment-naive patients.

Design, Setting, and Participants

This was a single-institution prognostic study from a high-volume center for pancreatic cancer. All specimens were obtained between January 1, 2009, and December 31, 2018, with a median (SE) follow-up of 20.2 (1.4) months. Analysis of the data was performed from October 1, 2019, to April 30, 2021. Targeted RNA sequencing of frozen FNA biopsy specimens from a discovery cohort of 23 patients was performed to identify genes with aberrant expression that was associated with patients' pathologic response to NAT. Immunohistochemical staining was performed on an additional 80 FNA biopsy specimens to assess expression of matrix metalloproteinase 7 (MMP-7) and its association with pathologic response. Receiver operating characteristic curves for prediction of favorable pathologic response were determined.

Results

In the discovery cohort (12 [52.1%] male; 3 [13.0%] Black and 20 [86.9%] White), RNA sequencing showed that lower MMP-7 expression was associated with favorable pathologic response (College of American Pathologists system scores of 0 [complete response] and 1 [marked response]). In the validation cohort (40 [50.0%] female; 9 [11.3%] Black and 71 [88.7%] White), patients with negative MMP-7 expression were significantly more likely to have a favorable pathologic response (odds ratio, 21.25; 95% CI, 6.19-72.95; P = .001). Receiver operating characteristic curves for prediction of favorable pathologic response from multivariable Cox proportional hazards regression modeling showed that MMP-7 expression increased the area under the curve from 0.726 to 0.906 (P < .001) even after stratifying by resectability status. The positive predictive value and negative predictive value of MMP-7 protein expression on FNA biopsy specimens in predicting unfavorable pathologic response (scores of 2 [partial response] or 3 [poor or no response]) were 88.2% and 73.9%, respectively.

Conclusions and Relevance

Assessment of MMP-7 expression on FNA biopsy specimens at the time of diagnosis may help identify patients who would benefit the most from NAT.

Short-Course or Total Neoadjuvant Chemotherapy in Resectable and Borderline Resectable Pancreatic Cancer - Current Status and Future Perspectives

Neoadjuvant therapy improves overall survival compared with a surgery-first approach in patients with borderline resectable pancreatic cancer (BRPC). Evidence of higher quality is required to determine whether neoadjuvant therapy has potential benefits and improves survival for patients with resectable pancreatic cancer (RPC). Most randomized controlled trials (RCTs) have explored short-course neoadjuvant chemotherapy (SNT), but total neoadjuvant chemotherapy (TNT) is now the experimental arm of ongoing RCTs. This article reviews the current status of SNT and TNT in RPC and BRPC, and provides perspectives of future challenges and research directions in this field.

Identification of an Immune-Related BAT Signature for Predicting Adjuvant Chemotherapy Response and Overall Survival in Patients with Resected Ductal Adenocarcinoma of the Pancreas

BACKGROUND

Adjuvant chemotherapy (ACT) is widely accepted in patients with pancreatic ductal adenocarcinoma (PDAC) after surgery; however, effective models for predicting ACT response are scarce. Thus, the objective of this study was to develop a novel signature for predicting its response and overall survival (OS) in resected PDAC patients.

METHODS

A total of 50 PDAC patients with the transcriptome expression profiles, information about chemotherapy, and relevant clinical data were retrieved from the Cancer Genome Atlas (TCGA), and twenty-nine patients with tissue specimens and clinical data from our hospital were included as a validation. A novel gene signature was developed using bioinformatic differentially expressed genes (DEGs) analysis, Lasso-penalized Cox regression, and multivariate Cox regression studies.

RESULTS

Between chemotherapy-resistant and chemotherapy-sensitive cohorts, 569 DEGs were identified, with 490 upregulated and 79 downregulated genes mainly specialized in the regulation of peptide/protein/hormone secretion, calcium ion homeostasis, and T cell activation regulation in biological processes. After Lasso-penalized Cox and multivariate Cox regression analysis, BAT (BCHE, ADH1A, and TNS4) signature was established to predict ACT response and OS. Moreover, BAT signature was verified as an independent risk factor for ACT response (p = 0.042) and OS (median OS: 17.5 months vs. 34.8 months, p = 0.040) and significantly associated with immune infiltrations (p < 0.05). Then, this signature was further validated as the independent risk factor for recurrence-free survival (RFS) in PDAC patients receiving postoperative ACT (median RFS: 9.0 months vs. not reached, p = 0.014), and tumor-infiltrating CD4+ and CD8+ T cells were further validated to be significantly decreased in tissues with higher BAT signature scores (p = 0.015 and 0.021, respectively).

CONCLUSION

The BAT signature is a novel formulated and independent risk factor for predicting ACT response and long-term survival in patients with resected PDAC. This signature could comprehensively reflect local immune-related response, tumor purity, potential biological behavior, and chemo drug susceptibility.

KCNN4-mediated Ca2+/MET/AKT axis is promising for targeted therapy of pancreatic ductal adenocarcinoma

As a member of the potassium calcium-activated channel subfamily, increasing evidence suggests that KCNN4 was associated with malignancies. However, the roles and regulatory mechanisms of KCNN4 in PDAC have been little explored. In this work, we demonstrated that the level of KCNN4 in PDAC was abnormally elevated, and the overexpression of KCNN4 was induced by transcription factor AP-1. KCNN4 was closely correlated with unfavorable clinicopathologic characteristics and poor survival. Functionally, we found that overexpression of KCNN4 promoted PDAC cell proliferation, migration and invasion. Conversely, the knockdown of KCNN4 attenuated the growth and motility of PDAC cells. In addition to these, knockdown of KCNN4 promoted PDAC cell apoptosis and led to cell cycle arrest in the S phase. In mechanistic investigations, RNA-sequence revealed that the MET-mediated AKT axis was essential for KCNN4, encouraging PDAC cell proliferation and migration. Collectively, these findings reveal a function of KCNN4 in PDAC and suggest it's an attractive therapeutic target and tumor marker. Our studies underscore a better understanding of the biological mechanism of KCNN4 in PDAC and suggest novel strategies for cancer therapy.

Evaluating Pancreatic and Biliary Neoplasms with Small Biopsy-Based Next Generation Sequencing (NGS): Doing More with Less

Simple Summary

Pancreatic cancer and cholangiocarcinoma are aggressive diseases mostly diagnosed at an advanced and inoperable stage. This review presents the value of next-generation sequencing (NGS) when performed on small biopsies—including fine-needle aspiration/biopsy samples, brushings, pancreatic juice and bile, and also blood—in the field of pancreatobiliary neoplasia. NGS could guide physicians while evaluating pancreatic solid and cystic lesions or suspicious biliary strictures, performing surveillance in high-risk individuals, or monitoring the disease and assessing prognosis in already diagnosed cancer patients. Evidence suggests that NGS performed on small biopsies is a robust tool for the diagnosis and pre-operative risk stratification of pancreatic and biliary lesions, whereas it also carries significant prognostic and therapeutic value. However, effective standardization of the pre-analytical and analytical assay parameters used for each clinical scenario is needed to fully implement NGS into routine practice and provide more personalized management in patients with suspected or established pancreatobiliary neoplasia.

Abstract

Pancreatic cancer and cholangiocarcinoma are lethal diseases mainly diagnosed at an inoperable stage. As pancreatobiliary surgical specimens are often unavailable for further molecular testing, this review aimed to highlight the diagnostic, prognostic, and therapeutic impact of next-generation sequencing (NGS) performed on distinct small biopsies, including endoscopic ultrasound fine-needle aspirations and biopsies of pancreatic solid and cystic lesions, biliary duct brushings, and also “liquid biopsies” such as the pancreatic juice, bile, and blood. NGS could clarify indeterminate pancreatic lesions or biliary strictures, for instance by identifying TP53 or SMAD4 mutations indicating high-grade dysplasia or cancer. It could also stratify pancreatic cystic lesions, by distinguishing mucinous from non-mucinous cysts and identifying high-risk cysts that should be excised in surgically fit patients, whereas the combination of cytology, elevated cystic CEA levels and NGS could improve the overall diagnostic accuracy. When NGS is performed on the pancreatic juice, it could stratify high-risk patients under surveillance. On the plasma, it could dynamically monitor the disease course and response to therapy. Notably, the circulating tumor DNA (ctDNA) levels have been associated with staging, grading, and survival. Lastly, NGS has shown potential in identifying potentially actionable molecular alterations. In conclusion, NGS applied on small biopsies could carry significant diagnostic, prognostic, and therapeutic value.

Establishment of organoids using residual samples from saline flushes during endoscopic ultrasound-guided fine-needle aspiration in patients with pancreatic cancer

Background and study aims  In patients with pancreatic cancer (PC), patient-derived organoid cultures can be useful tools for personalized drug selection and preclinical evaluation of novel therapies. To establish a less invasive method of creating organoids from a patient's tumor, we examined whether PC organoids can be established using residual samples from saline flushes (RSSFs) during endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA). Methods  Five patients with PC who underwent EUS-FNA were enrolled in a prospective study conducted at our institution. RSSFs obtained during EUS-FNA procedures were collected. An organoid culture was considered as established when ≥ 5 passages were successful. Organoid-derived xenografts were created using established organoids. Results  EUS-FNA was performed using a 22- or 25-gauge lancet needle without complications. Patient-derived organoids were successfully established in four patients (80.0 %) with the complete medium and medium for the selection of KRAS mutants. Organoid-derived xenografts were successfully created and histologically similar to EUS-FNA samples. Conclusions  Patient-derived PC organoids were successfully established using EUS-FNA RSSFs, which are produced as a byproduct of standard manipulations, but are usually not used for diagnosis. This method can be applied to all patients with PC, without additional invasive procedures, and can contribute to the development of personalized medicine and molecular research.

Predictive factors of operability after neoadjuvant chemotherapy in resectable or borderline resectable pancreatic cancer: a single-center retrospective study

BACKGROUND/AIMS

Recently neoadjuvant chemotherapy (NAC) for pancreatic cancer has been shown to be superior to upfront surgery, but it remains a matter of debate for resectable cases. In clinical practice, some resectable cases may become unresectable after NAC. This study aimed to reveal the outcomes after NAC and to clarify the characteristics of unresected cases.

METHODS

The medical records of 142 patients who underwent NAC between 2016 and 2020 were retrospectively reviewed. Patient characteristics, effectiveness of NAC, and outcomes were compared between the surgical group and non-surgical group (NSG). Furthermore, the risk of recurrence limited to in the patients who received NAC with gemcitabine plus nab-paclitaxel, which were mostly administered in this cohort, following R0/R1 resection was assessed.

RESULTS

The overall and R0 resection rates after NAC were 89.1% and 79.7%, respectively. The neutrophil to lymphocyte ratio (NLR) > 2.78 (p = 0.0120) and anatomical borderline resectable pancreatic cancer (p = 0.0044) revealed a statistically significantly correlation with the NSG. On the other hand, NAC week < 8 (p = 0.0285), radiological response, stable disease or progression disease (p = 0.0212), and pathological stage > IIA (P = 0.0003) were significantly associated with recurrence. The tumor response rate was approximately 26.1%, and three patients with ≥ 30% reduction of primary tumor lost excision opportunities because of metastasis, interstitial pneumonia, and vascular invasion.

CONCLUSIONS

This study shows incomplete tumor shrinkage benefits, but pre-NAC NLR is a predictive factor for predicting operability after NAC. The NLR can be easily calculated by normal blood test, and can be considered as a suitable marker of operability.

A systematic review and meta-analysis of the association between circulating tumor DNA (ctDNA) and prognosis in pancreatic cancer

Pancreatic cancer is a deadly disease with limited therapeutic options. Several strategies are being investigated to improve disease management, including the early diagnosis of recurrences and treatment tailoring by better prognosis estimation. Circulating tumor DNA (ctDNA) could be a promising tool in this regard, although the data is limited. Therefore, we conducted a systemical review and meta-analysis of the published studies on the association of ctDNA and survival outcomes in pancreatic cancer. In the pooled analysis, positive preoperative or postoperative ctDNA was associated with lower RFS/PFS (HR: 2.27, 95 % CI: 1.59-3.24, p < 0.001) and OS (HR: 2.04, 95 % CI: 1.29-3.21, p = 0.002) in localized pancreatic cancer. Similarly, positive baseline ctDNA was associated with lower RFS/PFS (HR: 2.61, 95 % CI: 1.94-3.51, p < 0.001) and OS (HR: 2.41, 95 % CI: 1.74-3.34, p < 0.001) in advanced pancreatic cancer. In conclusion, ctDNA could be a promising tool to individualize treatment planning and to improve outcomes in pancreatic cancer.

Borderline Resectable and Locally Advanced Pancreatic Cancers: A Review of Definitions, Diagnostics, Strategies for Treatment, and Future Directions

ABSTRACT

Locally advanced and borderline resectable pancreatic cancers are being increasingly recognized as a result of significant improvements in imaging modalities. The main tools used in diagnosis of these tumors include endoscopic ultrasound, computed tomography, magnetic resonance imaging, and diagnostic laparoscopy. The definition of what constitutes a locally advanced or borderline resectable tumor is still controversial to this day. Borderline resectable tumors have been treated with neoadjuvant therapy approaches that aim at reducing tumor size, thus improving the chances of an R0 resection. Both chemotherapy and radiotherapy (solo or in combination) have been used in this setting. The main chemotherapy agents that have shown to increase resectability and survival are FOLFORINOX (a combination of folinic acid, fluorouracil, irinotecan, and oxaliplatin) and gemcitabine-nab-paclitaxel. Surgery on these tumors remains a significantly challenging task for pancreatic surgeons. More studies are needed to determine the best agents to be used in the neoadjuvant and adjuvant settings, biologic markers for prognostic and operative predictions, and validation of previously published retrospective results.

Lymph Node Metastatic Patterns and Survival Predictors Based on Tumor Size in Pancreatic Ductal Adenocarcinoma

INTRODUCTION

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal malignancies. Larger tumor size is widely acknowledged to be associated with increased lymph node (LN) metastatic potential. However, the quantitative relationships between tumor size and LN metastasis or survival remain unclear. This study aims to quantify the objective relationship between tumor size and the prevalence of LN metastases across a spectrum primary tumor size.

METHODS

The Surveillance, Epidemiology, and End Results (SEER) database was used to identify 9958 patients with resected PDAC without distant metastasis. The prevalence of LN metastases, LN ratio (LNR), and N2/N1 ratio were assessed amongst different tumor sizes, and the relationships were displayed by matched curves.

RESULTS

In the enrolled cohort, age, tumor site, grade, American Joint Committee on Cancer (AJCC) 8th node staging, tumor size, chemotherapy, and radiotherapy were identified as significant independent predictors for overall survival (OS) and cancer-specific survival (CSS). For tumors within 1-40 mm in size, the prevalence of node-positive disease is closely modelled using a logarithmic formula [0.249 × ln (size) + 0.452] × 100%. The prevalence plateaued between 70% and 80% beyond 40 mm. The mean LNR increased in a stepwise manner as tumor size increased from 1-5 mm (LNR = 0.024) to 41-45 mm (LNR = 0.177); then, beyond 45 mm, it plateaued near 0.170. N2/N1 ratio gradually increased along with tumor size from 1-5 mm (N2/N1 = 0.286) to 41-45 mm (N2/N1 = 1.016), and when tumor size reached to 41-45 mm or more, the ratio stabilized around 1.000. In addition, significant survival prediction by AJCC N staging was observed when tumors ranging between 16 and 45 mm in size.

CONCLUSION

Regional LN involvement demonstrated a logarithmic growth with increasing tumor sizes in patients with resected PDAC . The probability of metastasis in each regional LN for resected PDAC with tumors greater than 40 mm in size was near 17.0% and their overall prevalence of LN metastasis was 70-80%. Among which, 50% of patients had an N2 stage. Such prediction may be a potential and promising tool for guiding lymphadenectomy in PDAC surgery.

Liquid Biopsy in Pancreatic Cancer: Are We Ready to Apply It in the Clinical Practice?

Pancreatic ductal adenocarcinoma (PDAC) exhibits the poorest prognosis of all solid tumors, with a 5-year survival of less than 10%. To improve the prognosis, it is necessary to advance in the development of tools that help us in the early diagnosis, treatment selection, disease monitoring, evaluation of the response and prognosis. Liquid biopsy (LB), in its different modalities, represents a particularly interesting tool for these purposes, since it is a minimally invasive and risk-free procedure that can detect both the presence of genetic material from the tumor and circulating tumor cells (CTCs) in the blood and therefore distantly reflect the global status of the disease. In this work we review the current status of the main LB modalities (ctDNA, exosomes, CTCs and cfRNAs) for detecting and monitoring PDAC.

Implementing biological markers as a tool to guide clinical care of patients with pancreatic cancer

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A major obstacle for the effective treatment of PDAC is its molecular heterogeneity.

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Stratification of PDAC using markers highly specific, reproducible, sensitive, easily measurable and inexpensive is necessary.

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At the early stages, clinician’s priority lies in rapid diagnosis, so that the patient receives surgery without delay.

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At advanced disease stages, priority is to determine the tumor subtype and select a suitable effective treatment.

A major obstacle for the effective treatment of pancreatic ductal adenocarcinoma (PDAC) is its molecular heterogeneity, reflected by the diverse clinical outcomes and responses to therapies that occur. The tumors of patients with PDAC must therefore be closely examined and classified before treatment initiation in order to predict the natural evolution of the disease and the response to therapy. To stratify patients, it is absolutely necessary to identify biological markers that are highly specific and reproducible, and easily measurable by inexpensive sensitive techniques. Several promising strategies to find biomarkers are already available or under development, such as the use of liquid biopsies to detect circulating tumor cells, circulating free DNA, methylated DNA, circulating RNA, and exosomes and extracellular vesicles, as well as immunological markers and molecular markers. Such biomarkers are capable of classifying patients with PDAC and predicting their therapeutic sensitivity. Interestingly, developing chemograms using primary cell lines or organoids and analyzing the resulting high-throughput data via artificial intelligence would be highly beneficial to patients. How can exploiting these biomarkers benefit patients with resectable, borderline resectable, locally advanced, and metastatic PDAC? In fact, the utility of these biomarkers depends on the patient's clinical situation. At the early stages of the disease, the clinician's priority lies in rapid diagnosis, so that the patient receives surgery without delay; at advanced disease stages, where therapeutic possibilities are severely limited, the priority is to determine the PDAC tumor subtype so as to estimate the clinical outcome and select a suitable effective treatment.