Adjuvant treatment for pancreatic cancer

Glucose-to-Lymphocyte Ratio (GLR) as an Independent Prognostic Factor in Patients with Resected Pancreatic Ductal Adenocarcinoma-Cohort Study

Background: We retrospectively evaluated the usefulness of an elevated glucose-to-lymphocyte ratio (GLR) as a sensitive prognostic biomarker of disease-specific survival in 338 patients who underwent surgical resection of pancreatic ductal adenocarcinoma (PDAC). Methods: The optimal GLR cutoff value was determined using the method of Contal and O'Quigley. Patient demographics, clinical information, and imaging data were analyzed to identify preoperative predictors of long-term survival outcomes. Results: Elevated GLR correlated significantly with aggressive tumor biologic behaviors, such as a high carbohydrate antigen (CA) 19-9 level (p = 0.003) and large tumor size (p = 0.011). Multivariate analysis identified (1) GLR > 92.72 [hazard ratio (HR) = 2.475, p < 0.001], (2) CA 19-9 level > 145.35 (HR = 1.577, p = 0.068), and (3) symptoms (p = 0.064) as independent predictors of long-term, cancer-specific survival. These three risk factors were used to group patients into groups 1 (0 factors), 2 (1-2 factors), and 3 (3 factors), which corresponded to significantly different 5-year overall survival rates (50.2%, 34.6%, and 11.7%, respectively; p < 0.001). Conclusions: An elevated preoperative GLR is associated with aggressive tumor characteristics and is an independent predictor of poor postoperative prognosis in patients with PDAC. Further prospective studies are required to verify these findings.

From standard therapies to monoclonal antibodies and immune checkpoint inhibitors - an update for reconstructive surgeons on common oncological cases

Malignancies represent a persisting worldwide health burden. Tumor treatment is commonly based on surgical and/or non-surgical therapies. In the recent decade, novel non-surgical treatment strategies involving monoclonal antibodies (mAB) and immune checkpoint inhibitors (ICI) have been successfully incorporated into standard treatment algorithms. Such emerging therapy concepts have demonstrated improved complete remission rates and prolonged progression-free survival compared to conventional chemotherapies. However, the in-toto surgical tumor resection followed by reconstructive surgery oftentimes remains the only curative therapy. Breast cancer (BC), skin cancer (SC), head and neck cancer (HNC), and sarcoma amongst other cancer entities commonly require reconstructive surgery to restore form, aesthetics, and functionality. Understanding the basic principles, strengths, and limitations of mAB and ICI as (neo-) adjuvant therapies and treatment alternatives for resectable or unresectable tumors is paramount for optimized surgical therapy planning. Yet, there is a scarcity of studies that condense the current body of literature on mAB and ICI for BC, SC, HNC, and sarcoma. This knowledge gap may result in suboptimal treatment planning, ultimately impairing patient outcomes. Herein, we aim to summarize the current translational endeavors focusing on mAB and ICI. This line of research may serve as an evidence-based fundament to guide targeted therapy and optimize interdisciplinary anti-cancer strategies.

Trajectories of immune-related serum proteins and quality of life in patients with pancreatic and other periampullary cancer: the CHAMP study

BACKGROUND

There is still a profound lack of efficient therapeutic strategies against pancreatic and other periampullary adenocarcinoma. Surgery is seldom possible, leaving palliative chemotherapy the only option for most patients. Chemotherapy treatment is however often accompanied by serious side-effects, and the identification of biomarkers for early prediction of disease and treatment-associated symptoms could help alleviate patient suffering. This study investigated the dynamic interrelationship between immune-related serum proteins, routine biomarkers, and health-related quality of life (HRQoL) factors during chemotherapy treatment of patients enrolled in the prospective, observational study Chemotherapy, Host response And Molecular dynamics in Periampullary cancer (CHAMP).

METHODS

Proximity extension assay was applied to analyse 92 immune-associated proteins in longitudinal serum samples from 75 patients, 18 treated with curative and 57 with palliative intent. HRQoL data were available from all patients at baseline (BL), from 41 patients at three months, and from 23 patients at six months. Information on routine laboratory parameters albumin, CA19-9, CEA and CRP were collected from medical charts.

RESULTS

In total nine proteins; chemokine (C-C motif) ligand 23 (CCL23), cluster of differentiation 4 (CD4), cluster of differentiation 28 (CD28), decorin (DCN), galectin-1 (Gal-1), granzyme B (GZMB), granzyme H (GZMH), matrix metallopeptidase 7 (MMP7), and monocyte chemotactic protein-1 (MCP-1) were strongly correlated (Spearman's Rho ≤ -0.6 or ≥ 0.6) with either cognitive functioning (DCN), emotional functioning (DCN, MCP-1), dyspnoea (CD28, GZMB, GZMH) or insomnia (CCL23, CD4, Gal-1, MMP7) during treatment. Associations between routine laboratory parameters (CA 19-9, CA-125, CRP, CEA and albumin) and HRQoL factors were overall weaker. None of the investigated proteins were associated with pain.

CONCLUSIONS

This is, to our knowledge, the first study exploring associations between serum biomarkers and HRQoL in patients with pancreatic or other periampullary cancer, and some findings merit further validation. The associations of DCN and MCP-1with impaired cognitive and/or emotional functioning are of particular interest, given their established link to various neurodegenerative conditions. Chemotherapy is known to cause persistent cognitive dysfunction with effects on memory and executive function, referred to as "chemo brain". It would therefore be of great value to identify biomarkers for early detection and management of this debilitating condition.

TRIAL REGISTRATION

Clinical Trial Registration: NCT03724994.

Therapeutic Strategies for Pancreatic-Cancer-Related Type 2 Diabetes Centered around Natural Products

Pancreatic ductal adenocarcinoma (PDAC), a highly malignant neoplasm, is classified as one of the most severe and devastating types of cancer. PDAC is a notable malignancy that exhibits a discouraging prognosis and a rising occurrence. The interplay between diabetes and pancreatic cancer exhibits a reciprocal causation. The identified metabolic disorder has been observed to possess noteworthy consequences on health outcomes, resulting in elevated rates of morbidity. The principal mechanisms involve the suppression of the immune system, the activation of pancreatic stellate cells (PSCs), and the onset of systemic metabolic disease caused by dysfunction of the islets. From this point forward, it is important to recognize that pancreatic-cancer-related diabetes (PCRD) has the ability to increase the likelihood of developing pancreatic cancer. This highlights the complex relationship that exists between these two physiological states. Therefore, we investigated into the complex domain of PSCs, elucidating their intricate signaling pathways and the profound influence of chemokines on their behavior and final outcome. In order to surmount the obstacle of drug resistance and eliminate PDAC, researchers have undertaken extensive efforts to explore and cultivate novel natural compounds of the next generation. Additional investigation is necessary in order to comprehensively comprehend the effect of PCRD-mediated apoptosis on the progression and onset of PDAC through the utilization of natural compounds. This study aims to examine the potential anticancer properties of natural compounds in individuals with diabetes who are undergoing chemotherapy, targeted therapy, or immunotherapy. It is anticipated that these compounds will exhibit increased potency and possess enhanced pharmacological benefits. According to our research findings, it is indicated that naturally derived chemical compounds hold potential in the development of PDAC therapies that are both safe and efficacious.

Cancer "Avatars": Patient-Derived Xenograft Growth Correlation with Postoperative Recurrence and Survival in Pancreaticobiliary Cancer

BACKGROUND

Pancreaticobiliary (PB) cancers are a diverse group of cancers with poor prognoses and high rates of recurrence after resection. Patient-derived xenografts (PDX), created from surgical specimens, provide a reliable preclinical research platform and high-fidelity cancer model from which to study these malignancies with consistent recapitulation of their original patient tumors in vivo. However, the relationship between PDX engraftment success (growth or no growth) and patient oncologic outcomes has not been well studied. We sought to evaluate the correlation between successful PDX engraftment and survival in several PB exocrine carcinomas, including the pancreatic and biliary tract.

STUDY DESIGN

In accordance with IRB and Institutional Animal Care and Use Committee protocols and with appropriate consent and approval, excess tumor tissue obtained from surgical patients was implanted into immunocompromised mice. Mice were monitored for tumor growth to determine engraftment success. PDX tumors were verified to recapitulate their tumors of origin by a hepatobiliary pathologist. Xenograft growth was correlated with clinical recurrence and overall survival data.

RESULTS

A total of 384 PB xenografts were implanted. The successful engraftment rate was 41% (158/384). We found that successful PDX engraftment was highly associated with both recurrence-free survival (p < 0.001) and overall survival (p < 0.001) outcomes. Successful PDX tumor generation occurs significantly in advance of clinical recurrences in their corresponding patients (p < 0.001).

CONCLUSIONS

Successful PB cancer PDX models predict recurrence and survival across tumor types and may provide critical lead time to alter patients' surveillance or treatment plans before cancer recurrence.

Serious complications of pancreatoduodenectomy correlate with lower rates of adjuvant chemotherapy: Results from the recurrence after Whipple's (RAW) study

INTRODUCTION

Adjuvant chemotherapy (AC) can prolong overall survival (OS) after pancreatoduodenectomy (PD) for pancreatic ductal adenocarcinoma (PDAC). However, fitness for AC may be influenced by postoperative recovery. We aimed to investigate if serious (Clavien-Dindo grade ≥ IIIa) postoperative complications affected AC rates, disease recurrence and OS.

MATERIALS AND METHODS

Data were extracted from the Recurrence After Whipple's (RAW) study (n = 1484), a retrospective study of PD outcomes (29 centres from eight countries). Patients who died within 90-days of PD were excluded. The Kaplan-Meier method was used to compare OS in those receiving or not receiving AC, and those with and without serious postoperative complications. The groups were then compared using univariable and multivariable tests.

RESULTS

Patients who commenced AC (vs no AC) had improved OS (median difference: (MD): 201 days), as did those who completed their planned course of AC (MD: 291 days, p < 0.0001). Those who commenced AC were younger (mean difference: 2.7 years, p = 0.0002), more often (preoperative) American Society of Anesthesiologists (ASA) grade I-II (74% vs 63%, p = 0.004) and had less often experienced a serious postoperative complication (10% vs 18%, p = 0.002). Patients who developed a serious postoperative complication were less often ASA grade I-II (52% vs 73%, p = 0.0004) and less often commenced AC (58% vs 74%, p = 0.002).

CONCLUSION

In our multicentre study of PD outcomes, PDAC patients who received AC had improved OS, and those who experienced a serious postoperative complication commenced AC less frequently. Selected high-risk patients may benefit from targeted preoperative optimisation and/or neoadjuvant chemotherapy.

An analysis of time to treatment in patients with pancreatic adenocarcinoma

BACKGROUND

Currently, no guidelines exist regarding the appropriate time from diagnosis to treatment among pancreatic adenocarcinoma patients. Herein, we aim to define the median time to treatment in pancreatic adenocarcinoma, factors associated with treatment delay, and prognostic significance.

METHODS

We conducted a retrospective study of pancreatic adenocarcinoma patients, stage I-IV, at a tertiary referral center (2017-2020). We subdivided time to treatment (days) into 4 components: (1) Ti: symptom onset to initial provider evaluation, (2) Tii: initial provider evaluation to diagnosis, (3) Tiii: diagnosis to specialist consultation, (4) Tiv: specialist visit to treatment.

RESULTS

In total, 217 patients met the inclusion criteria. The median Ti, Tii, Tiii, and Tiv were 20, 12, 4, and 14 days, respectively. The total time to treatment was 75 days. Patients with weight loss had longer Ti (β = 108.6). More frequent hospitalizations (β = 19.5) and misdiagnosis (β = 33.4) were associated with longer Tii. Patients with a history of malignancy (β = 15) or active treatment of a second disease (β = 19.4) had longer Tiii. Poor performance status (β = 6.2) or private insurance (β = 50.2) were associated with a longer Tiv. Black patients had longer Ti+ii+iii+iv (β = 100). Time to treatment was not associated with overall survival (P > .05).

CONCLUSION

It takes a median time of less than a month for a patient with pancreatic adenocarcinoma to start treatment, even after they visit a primary provider. The greatest opportunity to shorten the overall time to treatment is by having patients seek medical attention earlier (Ti).

A Delay in Adjuvant Therapy Is Associated With Worse Prognosis Only in Patients With Transitional Circulating Tumor Cells After Resection of Pancreatic Ductal Adenocarcinoma

OBJECTIVES

The aim of the study was to assess the association of circulating tumor cells (CTCs) with survival as a biomarker in pancreatic ductal adenocarcinoma (PDAC) within the context of a delay in the initiation of adjuvant therapy.

BACKGROUND

Outcomes in patients with PDAC remain poor and are driven by aggressive systemic disease. Although systemic therapies improve survival in resected patients, factors such as a delay in the initiation of adjuvant therapy are associated with worse outcomes. CTCs have previously been shown to be predictive of survival.

METHODS

A retrospective study was performed on PDAC patients enrolled in the prospective CircuLating tUmor cellS in pancreaTic cancER trial (NCT02974764) on CTC-dynamics at the Johns Hopkins Hospital. CTCs were isolated based on size (isolation by size of epithelial tumor cells; Rarecells) and counted and characterized by subtype using immunofluorescence. The preoperative and postoperative blood samples were used to identify 2 CTC types: epithelial CTCs (eCTCs), expressing pancytokeratin, and transitional CTCs (trCTCs), expressing both pancytokeratin and vimentin. Patients who received adjuvant therapy were compared with those who did not. A delay in the receipt of adjuvant therapy was defined as the initiation of therapy ≥8 weeks after surgical resection. Clinicopathologic features, CTCs characteristics, and outcomes were analyzed.

RESULTS

Of 101 patients included in the study, 43 (42.5%) experienced a delay in initiation and 20 (19.8%) did not receive adjuvant therapy. On multivariable analysis, the presence of trCTCs ( P =0.002) and the absence of adjuvant therapy ( P =0.032) were associated with worse recurrence-free survival (RFS). Postoperative trCTC were associated with poorer RFS, both in patients with a delay in initiation (12.4 vs 17.9 mo, P =0.004) or no administration of adjuvant chemotherapy (3.4 vs NR, P =0.016). However, it was not associated with RFS in patients with timely initiation of adjuvant chemotherapy ( P =0.293).

CONCLUSIONS

Postoperative trCTCs positivity is associated with poorer RFS only in patients who either experience a delay in initiation or no receipt of adjuvant therapy. This study suggests that a delay in the initiation of adjuvant therapy could potentially provide residual systemic disease (trCTCs) a window of opportunity to recover from the surgical insult. Future studies are required to validate these findings and explore the underlying mechanisms involved.

Prognostic Factors in Resected Pancreatic Ductal Adenocarcinoma: Is Neutrophil-Lymphocyte Ratio a Useful Marker?

BACKGROUND

The aim of this study is to analyze the role of neutrophil-lymphocyte ratio (NLR) and its variation pre- and postoperatively (delta NLR) in the overall survival after pancreatectomy for pancreatic ductal adenocarcinoma (PDAC) at a single center and to identify factors associated with overall survival.

METHODS

A retrospective study of consecutive patients undergoing pancreatectomy due to PDAC or undifferentiated carcinoma from January 2010 to January 2020 was performed. Association between the evaluated factors and overall survival was analyzed using a log-rank test and Cox proportional hazard regression model.

RESULTS

Overall, 242 patients underwent pancreatectomy for PDAC or undifferentiated carcinoma. OS was 22.8 months (95% confidence interval (CI): 19.5-29), and survival rates at 1, 3, and 5 years were 72%, 32.5%, and 20.8%, respectively. NLR and delta NLR were not significantly associated with survival (hazard ratio (HR) = 1.14, 95%CI: 0.77-1.68, p = 0.5). Lymph node ratio was significantly associated (HR = 1.66, 95%CI: 1.21-2.26, p = 0.001) in the bivariate analysis. In multivariable analysis, the only factors that were significantly associated with survival were perineural invasion (HR = 1.94, 95%CI: 1.21-3.14, p = 0.006), surgical margin (HR = 1.83, 95%CI: 1.10-3.02, p = 0.019), tumor size (HR = 1.01, 95%CI: 1.003-1.027, p = 0.16), postoperative CA 19-9 level (HR = 1.001, p < 0.001), and completion of adjuvant treatment (HR = 0.53, 95%CI: 0.35-0.8, p = 0.002).

CONCLUSION

Neutrophil-lymphocyte ratio and delta NLR were not associated with the overall survival in this cohort. Risk factors such as perineural invasion, surgical margins, CA19-9 level, and tumor size showed worse survival in this study, whereas completing adjuvant treatment was a protective factor.

A 3D-Printed Graphene BioFuse Implant for Postsurgical Adjuvant Therapy of Cancer: Proof of Concept in 2D- and 3D-Spheroid Tumor Models

Three-dimensional printing is an emerging technology that is finding its niche applications in diverse fields owing to its flexibility concerning personalization and design. Surgery followed by adjuvant therapy is the standard treatment plan in most cancers from stage I to stage III. Most of the available adjuvant therapies, like chemotherapy, radiation therapy, immunotherapy, hormonal therapy, etc., are associated with severe side effects that considerably reduce the quality of life of patients. In addition, there is always the chance of tumor recurrence or metastasis development followed by surgery. This investigation reports the development of a 3D-printed, biodegradable, laser-responsive implant with a chemo-combined thermal ablating potential for adjuvant therapy of cancer. The 3D-printable ink was developed using poly(l-lactide) and hydroxypropyl methylcellulose as the base polymer, doxorubicin as the chemotherapeutic agent, and reduced graphene oxide as the photothermal ablating agent. The personalized implant released the drug pH-dependently (p value < 0.0001) for an extended period (93.55 ± 1.80% → 28 days). The 3D-printed implant exhibited acceptable biophysical properties (tensile strength: 3.85 ± 0.15 MPa; modulus: 92.37 ± 11.50 MPa; thickness: 110 μm) with laser-responsive hyperthermia (ΔT: 37 ± 0.9 °C → 48.5 ± 1.07 °C; 5 min; 1.5 W/cm²) and inherent biodegradable property (SEM analysis). The 3D-printed implant was evaluated for its therapeutic potential in 2D- and 3D-spheroid tumor models (MDA-MB 231 and SCC 084 2D cells) employing MTT cytotoxicity assay, apoptosis assay, cell cycle analysis, and gene expression analysis. The biomolecular aspects and biomechanics of the 3D-printed BioFuse implant were also evaluated by determining the effect of treatment on the expression levels of HSP1A, Hsp70, BAX, and PTEN. It is advocated that the knowledge developed in this project will significantly assist and advance the science aiming to develop a clinically translatable postsurgical adjuvant therapy for cancer.

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.

Pancreatic cancer

The need for a common education and training track in surgical oncology across Europe has been emphasized. ESSO provides several hands-on courses for skills training and face-to-face discussions. The core curriculum provides a framework for the overall theoretical requirements in surgical oncology. The UEMS/EBSQ fellowship exam is designed to test core competencies in the candidate's core knowledge in their prespecified area of expertise. A core set of points for each cancer type is lacking. Hence, a condensed outline of themed expected to be covered in the curriculum and relevant to an optimal practice in surgical oncology is provided. This article outlines pancreatic cancer.

Serious complications of pancreatoduodenectomy correlate with lower rates of adjuvant chemotherapy: Would high-risk patients benefit from neoadjuvant therapy?

INTRODUCTION

Patients who suffer a serious complication of pancreatoduodenectomy (PD) may have their adjuvant chemotherapy (AC) delayed or omitted as a result. We aimed to investigate whether PD complications affected AC rates.

MATERIALS AND METHODS

A retrospective analysis of all PD patients with histologically-confirmed pancreatic ductal adenocarcinoma (2006-2015) was performed; 90-day mortality patients were excluded. Patients who commenced AC were compared to those who did not (morbidity rates and survival) and patients who developed selected postoperative complications were compared to those who did not (AC rates and survival).

RESULTS

157 patients were included and 90-day mortality was 3.8%. Of the remaining patients, 102 (68.5%) received AC (AC data unavailable for two patients). Survival was longer in the AC group (p = 0.004). AC patients had less frequently experienced a postoperative chest infection (8.82% vs 34.0%, p = 0.0003) or a postoperative complication which was Clavien-Dindo (CD) grade ≥ II (29.4% vs 57.4%, p = 0.0019) or ≥ III (6.86% vs 21.3%, p = 0.023). Patients who experienced a postoperative chest infection (36.0% vs 75.0%, p = 0.0003) or a postoperative complication which was CD grade ≥ II (48.9% vs 73.1%, p = 0.0099) or ≥ III (29.4% vs 70.3%, p = 0.0018) less frequently commenced AC.

CONCLUSION

Patients who received AC had less frequently experienced a serious postoperative complication. Efforts should be made to preoperatively identify those who are high-risk for a serious complication as this cohort may benefit from neoadjuvant therapy.

Pharmacotherapeutic options for pancreatic ductal adenocarcinoma

INTRODUCTION

Pancreatic ductal adenocarcinoma (PDAC) is a lethal malignancy projected to be the 2^nd leading cause of cancer related death in the USA by 2030. This manuscript discusses current and evolving treatment approaches in patients with pancreatic cancer.

AREAS COVERED

PDAC is classified as: a) resectable, b) borderline resectable, c) unresectable (locally advanced and metastatic). The standard of care for patients who present with resectable pancreatic adenocarcinoma is six months of adjuvant modified (m) FOLFIRINOX, gemcitabine plus capecitabine, or single agent gemcitabine. For many reasons, there has been a paradigm shift to employing neoadjuvant chemotherapy. For resectable and borderline resectable patients, we generally start with systemic therapy and reevaluate resectability with subsequent scans specifically when the tumor is located in the head or body of the pancreas. Combined chemoradiation therapy can be employed in select patients. The standard of care for metastatic PDAC is FOLFIRINOX or gemcitabine and nab-paclitaxel. Germline and somatic genomic profiling should be obtained in all patients. Patients with a germline BRCA mutation can receive upfront gemcitabine and cisplatin.

EXPERT OPINION

Thorough understanding of molecular pathogenesis in PDAC has opened various therapeutic avenues. We remain optimistic that future treatment modalities such as targeted therapies, cellular therapies and immunotherapy will further improve survival in PDAC.

Risk factors for exocrine pancreatic insufficiency after pancreatic surgery: a systematic review and meta-analysis

BACKGROUND

Patients should be informed beforehand of the risk factors for exocrine pancreatic insufficiency (ExoPI) after pancreatic surgery; however, there are no clear identified risk factors for this condition. This study aimed to identify the preoperative, perioperative and postoperative risk factors for ExoPI after pancreatic surgery.

METHODS

We conducted a systematic search of PubMed, Scopus, SAGE, CINAHL Plus and Taylor & Francis from inception to Mar. 7, 2021, for full-text articles that included patients who had undergone pancreatic surgery. The primary outcome was the number of ExoPI events and any risk factors evaluated. We used the Newcastle-Ottawa Scale to assess study quality.

RESULTS

Twenty studies involving 4131 patients (2312 [52.3%] male, mean age 60.12 [standard deviation 14.07] yr) were included. Of the 4131 patients, 1651 (40.0%) had postoperative ExoPI. Among the 11 factors evaluated, the significant risk factors were preoperative main pancreatic duct (MPD) diameter greater than 3 mm (odds ratio [OR] 4.50, 95% confidence interval [CI] 1.06-19.05), pancreaticoduodenectomy (PD) as the surgical treatment procedure (OR 3.31, 95% CI 1.92-5.68), pancreaticogastrostomy (PG) as the anastomotic procedure (OR 3.13, 95% CI 1.83-5.35), hard pancreatic texture (OR 2.93, 95% CI 1.99-4.32) and adjuvant chemotherapy (OR 2.50, 95% CI 1.54-4.04). Gender, history of diabetes mellitus or endocrine pancreatic insufficiency (EndoPI), underlying diseases, de novo diabetes or EndoPI, pylorus-preserving PD and postoperative pancreatic fistula were not risk factors for ExoPI after pancreatic surgery.

CONCLUSION

Preoperative MPD diameter greater than 3 mm, PD, PG reconstruction, hard pancreatic texture and adjuvant chemotherapy were risk factors for the development of ExoPI after pancreatic surgery. The findings should provide useful information for patients to reduce postoperative dissatisfaction and improve quality of life.

Methionine aminopeptidase 2 as a potential target in pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDA) is an aggressive metastatic cancer with a very low survival rate. This tumor is hypovascularized and characterized by severe hypoxic regions, yet these regions are not impeded by the oxidative stress in their microenvironment. PDA's high resilience raises the need to find new effective therapeutic targets. This study investigated the suitability of methionine aminopeptidase 2 (MetAp2), a metallopeptidase known to play an important role in tumor progression, as a new target for treating PDA. In our examination of patient-derived PDA tissues, we found that MetAp2 is highly expressed in metastatic regions compared with primary sites. At the cellular level, we found that the basal expression levels of MetAp2 in pancreatic cancer cells were higher than its levels in endothelial cells. Pancreatic cancer cells showed a significant suppression of proliferation in a dose-dependent manner upon exposure to TNP-470, a selective MetAp2 inhibitor. In addition, a significant reduction in glutathione (GSH) levels - known for its importance in alleviating oxidative stress - was detected in all treated cells, suggesting a possible anti-cancer activity mechanism that would be feasible for treating highly hypoxic PDA tumors. Furthermore, in an orthotopic pancreatic cancer murine model, systemic oral treatment with a MetAp2 inhibitor significantly reduced tumors' growth. Taken together, our findings indicate that MetAp2 enhances tumor sensitivity to hypoxia and may provide an effective target for treating hypoxic tumors with high expression levels of MetAp2.

Nanosilver inhibits the progression of pancreatic cancer by inducing a paraptosis-like mixed type of cell death

Silver has been in clinical use since ancient times and silver nanoparticles (AgNPs) have attracted attention in cancer therapy. We investigated the mechanisms by which AgNPs inhibit pancreatic ductal adenocarcinoma (PDAC). AgNPs were synthesized and 3 human PDAC and 2 nonmalignant primary cell lines were treated with AgNPs. MTT, MAPK, colony, spheroid and scratch assays, Western blotting, TEM, annexin V, 7-AAD, and H2DCFDA staining, FACS analysis, mRNA array and bioinformatics analyses, tumor xenograft transplantation, and immunohistochemistry of the treated cells were performed. We found that minimal AgNPs amounts selectively eradicated PDAC cells within a few hours. AgNPs inhibited cell migration and spheroid and colony formation, damaged mitochondria, and induced paraptosis-like cell death with the presence of cytoplasmic vacuoles, dilation of the ER and mitochondria, ROS formation, MAPK activity, and p62 and LC3b expression, whereas effects on the nucleus, DNA fragmentation, or caspases were not detectable. AgNPs strongly decreased tumor xenograft growth without side effects and reduced the expression of markers for proliferation and DNA repair, but upregulated paraptosis markers. The results highlight nanosilver as complementary agent to improve the therapeutic efficacy in pancreatic cancer.

Machine-Learning-Based Bibliometric Analysis of Pancreatic Cancer Research Over the Past 25 Years

Machine learning and semantic analysis are computer-based methods to evaluate complex relationships and predict future perspectives. We used these technologies to define recent, current and future topics in pancreatic cancer research. Publications indexed under the Medical Subject Headings (MeSH) term 'Pancreatic Neoplasms' from January 1996 to October 2021 were downloaded from PubMed. Using the statistical computing language R and the interpreted, high-level, general-purpose programming language Python, we extracted publication dates, geographic information, and abstracts from each publication's metadata for bibliometric analyses. The generative statistical algorithm "latent Dirichlet allocation" (LDA) was applied to identify specific research topics and trends. The unsupervised "Louvain algorithm" was used to establish a network to identify relationships between single topics. A total of 60,296 publications were identified and analyzed. The publications were derived from 133 countries, mostly from the Northern Hemisphere. For the term "pancreatic cancer research", 12,058 MeSH terms appeared 1,395,060 times. Among them, we identified the four main topics "Clinical Manifestation and Diagnosis", "Review and Management", "Treatment Studies", and "Basic Research". The number of publications has increased rapidly during the past 25 years. Based on the number of publications, the algorithm predicted that "Immunotherapy", Prognostic research", "Protein expression", "Case reports", "Gemcitabine and mechanism", "Clinical study of gemcitabine", "Operation and postoperation", "Chemotherapy and resection", and "Review and management" as current research topics. To our knowledge, this is the first study on this subject of pancreatic cancer research, which has become possible due to the improvement of algorithms and hardware.

Immunotherapy in Combination with Well-Established Treatment Strategies in Pancreatic Cancer: Current Insights

Pancreatic ductal adenocarcinoma (PDAC) is the most common type of pancreatic cancer and fourth most common cause of death in developed countries. Despite improved survival rates after resection combined with adjuvant chemotherapy or neoadjuvant chemotherapy, recurrence still occurs in a high percentage of patients within the first 2 years after resection. Immunotherapy aims to improve antitumor immune responses and reduce toxicity providing a more specific, targeted therapy compared to chemotherapy and has been proved an efficient therapeutic tool for many solid tumors. In this work, we present the latest advances in PDAC treatment using a combination of immunotherapy with other interventions such as chemotherapy and/or radiation both at neoadjuvant and adjuvant setting. Moreover, we outline the role of the tumor microenvironment as a key barrier to immunotherapy efficacy and examine how immunotherapy biomarkers may be used to detect immunotherapy’s response.

FGD5‑AS1 is an oncogenic lncRNA in pancreatic cancer and regulates the Wnt/β‑catenin signaling pathway via miR‑577

The objective of the present study was to clarify the expression characteristics of long non-coding RNA (lncRNA) FGD5 antisense RNA 1 (FGD5-AS1) in pancreatic cancer, as well as its biological function and underlying mechanism. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was utilized for the detection of FGD5-AS1 and microRNA (miR)-577 expression levels in pancreatic cancer tissues. Transfection was performed to upregulate or downregulate FGD5-AS1 in pancreatic cancer cell lines. MTT and Transwell assays were then utilized to detect the proliferation, migration and invasion of cancer cells, respectively. Subsequently, dual-luciferase reporter gene assay, RNA immunoprecipitation assay, RNA pull-down assay, RT-qPCR, western blotting, and Pearson's correlation analysis were employed to confirm the regulatory relationships among FGD5-AS1, miR-577, low-density lipoprotein receptor-related protein 6 (LRP6) and β-catenin. Western blotting was employed to determine the expression levels of Axin2, cyclin D1 and c-Myc. The expression level of FGD5-AS1 was upregulated in pancreatic cancer tissues and cell lines. FGD5-AS1 knockdown inhibited pancreatic cancer cell proliferation, migration and invasion. By contrast, miR-577 was significantly inhibited in pancreatic cancer cells and tissues; its downregulation promoted pancreatic cancer cell proliferation, migration and invasion, and reversed the effects of FGD5-AS1 knockdown on pancreatic cancer cells. In addition, it was revealed that miR-577 was a target of FGD5-AS1, and FGD5-AS1 could modulate the expression levels of LRP6, β-catenin, Axin2, cyclin D1 and c-Myc via suppressing miR-577. In conclusion, in pancreatic cancer, highly expressed FGD5-AS1 activated the Wnt/β-catenin signaling and promoted cancer cell proliferation, migration and invasion via suppression of miR-577.

State-of-the-art surgery for pancreatic cancer

BACKGROUND

The d evelopment of surgical techniques and specialization and specifically complication management in pancreatic surgery have improved surgical outcomes as well as oncological results in pancreatic surgery in recent decades. Historical morbidity and especially mortality rates of up to 80% have decreased to below 5% today. This review summarizes the current state of the art in pancreatic cancer surgery.

METHODS

The present literature and clinical experience are summarized to give an overview of the present best practice in pancreatic surgery as one of the most advanced surgical disciplines today.

RESULTS

Based on the available literature, three important aspects contribute to best patient care in pancreatic surgery, namely, surgical progress, interdisciplinary complication management, and multimodal oncological treatment in case of pancreatic cancer. In addition, minimally invasive and robotic procedures are currently fields of development and specific topics of research.

CONCLUSION

In experienced hands, pancreatic surgery-despite being one of the most challenging fields of surgery-is a safe domain today. The impact of multimodal, especially adjuvant, therapy for oncological indications is well established and evidence-based. New technologies are evolving and will be evaluated with high-evidence studies in the near future.

The importance of time-to-adjuvant treatment on survival with pancreatic cancer: A systematic review and meta-analysis

BACKGROUND

While adjuvant chemotherapy benefits patients with pancreatic ductal adenocarcinoma (PDAC), the importance of the time to initiation of adjuvant therapy remains unclear.

AIM

This study seeks to better understand whether the timing of postoperative chemotherapy initiation affects long-term outcomes in PDAC.

METHODS AND RESULTS

A systematic literature search was performed in Medline, Embase, and Cochrane Library in March 2020. Studies focused on the association between the timing of adjuvant therapy on long-term outcomes in resected PDAC patients were included. The impact of early and delayed therapy as defined by the respective studies was evaluated using forest plot analysis. Overall survival (OS) and disease-free survival (DFS) served as primary endpoints. Out of 3099 published articles, 10 retrospective studies met inclusion criteria. Combined, these studies included clinical data of 13 344 patients. The cut off used to define "early" and "delayed" treatment groups varied in the included studies ranging from 3 to 12 weeks. Due to this heterogeneity, a sub-group analysis of three time cut offs was performed: 3 to 5 weeks, 6 to 8 weeks, and 9 to 12 weeks. There was a significant decrease in OS and DFS when adjuvant therapy was delayed by 3 to 5 weeks after surgery (OS, pooled hazard ratio [HR] = 1.86, 95% confidence interval [CI] = 1.25-2.78; DFS, pooled HR = 1.62, 95% CI = 1.12-2.34). However, due to small sample size and limited studies in this subgroup analysis, the results may be indeterminate. There was no significant decrease in OS with delayed initiation of adjuvant therapy by 6 to 8 weeks and 9 to 12 weeks. Similarly, delay in adjuvant therapy beyond 3-5 weeks.

CONCLUSIONS

There was no conclusive evidence suggesting improved survival in patients starting treatment at various time cut offs. Studies investigating the extreme ends of the time-to-treatment spectrum may prove more informative.

The Oncogenic Signaling Disruptor, NDRG1: Molecular and Cellular Mechanisms of Activity

NDRG1 is an oncogenic signaling disruptor that plays a key role in multiple cancers, including aggressive pancreatic tumors. Recent studies have indicated a role for NDRG1 in the inhibition of multiple tyrosine kinases, including EGFR, c-Met, HER2 and HER3, etc. The mechanism of activity of NDRG1 remains unclear, but to impart some of its functions, NDRG1 binds directly to key effector molecules that play roles in tumor suppression, e.g., MIG6. More recent studies indicate that NDRG1s-inducing drugs, such as novel di-2-pyridylketone thiosemicarbazones, not only inhibit tumor growth and metastasis but also fibrous desmoplasia, which leads to chemotherapeutic resistance. The Casitas B-lineage lymphoma (c-Cbl) protein may be regulated by NDRG1, and is a crucial E3 ligase that regulates various protein tyrosine and receptor tyrosine kinases, primarily via ubiquitination. The c-Cbl protein can act as a tumor suppressor by promoting the degradation of receptor tyrosine kinases. In contrast, c-Cbl can also promote tumor development by acting as a docking protein to mediate the oncogenic c-Met/Crk/JNK and PI3K/AKT pathways. This review hypothesizes that NDRG1 could inhibit the oncogenic function of c-Cbl, which may be another mechanism of its tumor-suppressive effects.

Long-Term Survivors after Upfront Resection for Pancreatic Ductal Adenocarcinoma: An Actual 5-Year Analysis of Disease-Specific and Post-Recurrence Survival

BACKGROUND

Data on long-term actual survival in patients with surgically resected pancreatic ductal adenocarcinoma (PDAC) are limited. The aim of this study was to evaluate the actual 5-year disease-specific survival (DSS) and post-recurrence survival (PRS) in patients who underwent pancreatectomy for PDAC.

METHODS

Data from patients who underwent upfront surgical resection for PDAC between 2009 and 2014 were analyzed. Exclusion criteria included PDAC arising in the background of an intraductal papillary mucinous neoplasm and patients undergoing neoadjuvant therapy. All alive patients had a minimum follow-up of 60 months. Independent predictors of PRS, DSS, and survival > 5 years were searched.

RESULTS

Of the 176 patients included in this study, 48 (27%) were alive at 5 years, but only 20 (11%) had no recurrence. Median PRS was 12 months. In the 154 patients after disease recurrence, independent predictors of shorter PRS were total pancreatectomy, G3 tumors, early recurrence (< 12 months from surgery), and no treatment at recurrence. Median DSS was 36 months. Independent predictors of DSS were CA19-9 at diagnosis > 200 U/mL, total pancreatectomy, N + status, G3 tumors and perineural invasion. Only the absence of perineural invasion was a favorable independent predictor of survival > 5 years.

CONCLUSION

More than one-quarter of patients who underwent upfront surgery for PDAC were alive after 5 years, although only 11% of the initial cohort were cancer-free. Long-term survival can also be achieved in tumors with more favorable biology in an upfront setting followed by adjuvant chemotherapy.

G2M checkpoint pathway alone is associated with drug response and survival among cell proliferation-related pathways in pancreatic cancer

Given the severe side effects of the treatments and poor survival, prognostic and predictive biomarkers to guide management of pancreatic cancer are in critical need. We hypothesized that cell proliferation-related pathways are associated with drug response and survival in pancreatic cancer. Six Hallmark cell proliferation-related gene sets (G2M Checkpoint, E2F Targets, MYC Targets V1 and V2, Mitotic Spindle, p53 pathway) defined by MSigDB in gene set variant analysis were evaluated in 3 independent cohorts- TCGA-PAAD (n = 176), GSE57495 (n = 63), and GSE62452 (n = 69). G2M and E2F, as well as Mitotic and p53 pathway correlated highly with other gene sets. All pathways were significantly correlated with MKI67 expression and its proliferation score, but none with cytolytic activity and the rate of pathologically complete resection (R0). All pathways were significantly associated with high alteration and expression of KRAS gene except for MYC v1. G2M, E2F, and p53 pathway were significantly associated with high alteration of TP53 gene. Interestingly, different pathways correlated with the AUC of different cancer therapeutics, such as Gemcitabine (Mitotic: r = 0.706 [P = 0.01]), Paclitaxel (MYC v2: r = -0.636 [P < 0.05]), Apatinib (Mitotic: r = -0.556 [P = 0.03]), Palbociclib (E2F: r = 0.675 [P < 0.01]), and Sorafenib (G2M: r = -0.593 [P = 0.03]). Among all six pathways, only G2M was consistently associated with worse patient survival in all three cohorts. In conclusion, each cell proliferation-related pathway was predictive of a unique agent, and the G2M score alone predicts survival in pancreatic cancer.

European Cancer Organisation Essential Requirements for Quality Cancer Care (ERQCC): Pancreatic Cancer

European Cancer Organisation Essential Requirements for Quality Cancer Care (ERQCC) are written by experts representing all disciplines involved in cancer care in Europe. They give patients, health professionals, managers and policymakers a guide to essential care throughout the patient journey. Pancreatic cancer is an increasing cause of cancer mortality and has wide variation in treatment and care in Europe. It is a major healthcare burden and has complex diagnosis and treatment challenges. Care must be carried out only in pancreatic cancer units or centres that have a core multidisciplinary team (MDT) and an extended team of health professionals detailed here. Such units are far from universal in European countries. To meet European aspirations for comprehensive cancer control, healthcare organisations must consider the requirements in this paper, paying particular attention to multidisciplinarity and patient-centred pathways from diagnosis, to treatment, to survivorship.

Neoadjuvant and Adjuvant Therapy in Operable Pancreatic Cancer: Both Honey and Milk (but No Bread?)

Pancreatic cancer has a dismal prognosis. Resection is the best option for cure, supported by multimodal therapy to treat the systemic disease. While adjuvant therapy has become standard in those who are fit and who can tolerate the given regimen, the concept of perioperative (neoadjuvant) therapy is building momentum. The concepts of “borderline” and “locally advanced” have changed the previous dichotomized “resectable/non-resectable” into subcategories for which new algorithms have emerged, with neoadjuvant therapy discussed both for upfront resectable pancreatic cancer, for those deemed borderline resectable, and as “induction or conversion” therapy for locally advanced disease. The purpose of this invited commentary is to discuss some of the changing paradigms in multimodal therapy for operable pancreatic cancer. The PREOPANC trial presented randomized data on the role of neoadjuvant therapy for resectable and borderline cancers, but new questions have emerged. The role of combination therapy in the preoperative setting is discussed in the light of this trial. FOLFIRINOX has emerged as the most potent treatment regimen in the metastatic and adjuvant setting, but with no level I data to support neoadjuvant use yet. Several trials are ongoing to arrive at the best answer.

FOLFIRINOX regulated tumor immune microenvironment to extend the survival of patients with resectable pancreatic ductal adenocarcinoma

Background

Pancreatic ductal adenocarcinoma (PDAC) is one of the most deadly malignant tumors worldwide due to its ineffective diagnosis and poor prognosis. The longest median overall survival (OS) to PDAC patients has been provided by FOLFIRINOX. It is essential to identify the mechanisms of FOLFIRINOX to gain new insights for the treatment of PDAC.

Methods

We compared gene expression levels of PDAC patients who received neoadjuvant FOLFIRINOX prior to surgery with those of patients who received no neoadjuvant chemotherapy. Bioinformatics analysis was applied to screen differentially expressed genes (DEGs). Three microarray data sets were downloaded to analyze gene expression data between PDAC and adjacent non-tumor tissues. Overlapping DEGs were subjected to Kaplan-Meier survival analysis. The genes relating to poor outcomes and would be decreased after FOLFIRINOX were input into the Oncomine, University of Alabama Cancer (UALCAN), and LinkedOmics databases to analyze the gene expression and regulation networks.

Results

A total of 83 differentially expressed genes (DEGs) were screened and subjected to bioinformatics analysis, which indicated FOLFIRINOX influenced the immune microenvironment of PDAC. Seventy-three genes significantly associated with the OS of PDAC patients. A Venn diagram revealed CXCL5 and PLAU were related to poor outcomes and would decrease after FOLFIRINOX chemotherapy of PDAC patients. It turned out that CXCL5 participated in the immune response-regulating signaling pathway in PDAC patients.

Conclusions

FOLFIRINOX regulated tumor immunity by reducing expression of the immunosuppressive gene CXCL5, laying a foundation for further study of combination therapy of FOLFIRINOX and immunotherapy.

The Present Status of Immuno-Oncolytic Viruses in the Treatment of Pancreatic Cancer

Pancreatic ductal adenocarcinoma (PDAC) is the fifth leading cause of cancer-related death in Western countries. The incidence of PDAC has increased over the last 40 years and is projected to be the second leading cause of cancer death by 2030. Despite aggressive treatment regimens, prognosis for patients diagnosed with PDAC is very poor; PDAC has the lowest 5-year survival rate for any form of cancer in the United States (US). PDAC is very rarely detected in early stages when surgical resection can be performed. Only 20% of cases are suitable for surgical resection; this remains the only curative treatment when combined with adjuvant chemotherapy. Treatment regimens excluding surgical intervention such as chemotherapeutic treatments are associated with adverse effects and genetherapy strategies also struggle with lack of specificity and/or efficacy. The lack of effective treatments for this disease highlights the necessity for innovation in treatment options for patients diagnosed with early- to late-phase PDAC and immuno-oncolytic viruses (OVs) have been of particular interest since 2006 when the first oncolytic virus was approved as a therapy for nasopharyngeal cancers in China. Interest resurged in 2015 when T-Vec, an oncolytic herpes simplex virus, was approved in the United States for treatment of advanced melanoma. While many vectors have been explored, few show promise as treatment for pancreatic cancer, and fewer still have progressed to clinical trial evaluation. This review outlines recent strategies in the development of OVs targeting treatment of PDAC, current state of preclinical and clinical investigation and application.

Appraisal of 5-year recurrence-free survival after surgery in pancreatic ductal adenocarcinoma

BACKGROUND/PURPOSE

Pancreatic ductal adenocarcinoma (PDAC) is regarded as incurable, with a limited survival rate after curative resection. The aim of this study was to explore long-term survival and late recurrence of PDAC after surgery.

METHODS

Medical data of 859 patients who underwent resection between 1995 and 2014 were retrospectively examined. The clinicopathological features of the 5-year recurrence-free survivors and the patients with recurrent disease after 5 years were investigated separately.

RESULTS

Among the 768 patients who were finally included in this study, elevated CA 19-9, tumor size, poor differentiation, and positive lymph node metastasis were associated with recurrence. In 89 patients with 5-year RFS, age, tumor size, differentiation, and lymph node metastasis were statistically significant predictive factors. Among these patients, disease relapse occurred in 11 patients; age was the only difference compared to those who remained free of recurrence.

CONCLUSIONS

Most prognosticators failed to predict the risk of recurrence in the 5 years following surgery for PDAC, and recurrence can occur even at time points up to 100 months. Therefore, cure of PDAC cannot be guaranteed by a 5-year recurrence-free interval, and further studies into the inherent nature of PDAC are needed to develop adequate surveillance systems which may lead to improvements in survival.

The Diagnostic Accuracy of Mutant KRAS Detection from Pancreatic Secretions for the Diagnosis of Pancreatic Cancer: A Meta-Analysis

This meta-analysis aims to identify the diagnostic accuracy of mutations in the Kirsten Rat Sarcoma (KRAS) oncogene in the diagnosis of pancreatic ductal adenocarcinoma (PDAC). The survival of PDAC remains poor often due to the fact that disease is advanced at diagnosis. We analysed 22 studies, with a total of 2156 patients, to identify if the detection of KRAS mutations from pancreatic exocrine secretions yields sufficient specificity and sensitivity to detect patients with PDAC amongst healthy individuals. The majority of the studies were retrospective, samples were obtained endoscopically or surgically, and included comparator populations of patients with chronic pancreatitis and pre-malignant pancreatic lesions (PanIN) as well as healthy controls. We performed several analyses to identify the diagnostic accuracy for PDAC among these patient populations. Our results highlighted that the diagnostic accuracy of KRAS mutation for PDAC was of variable sensitivity and specificity when compared with PanINs and chronic pancreatitis, but had a higher specificity among healthy individuals. The sensitivity of this test must be improved to prevent missing early PDAC or PanINs. This could be achieved with rigorous prospective cohort studies, in which high-risk patients with normal cross-sectional imaging undergo surveillance following KRAS mutation testing.

The identification of candidate effective combination regimens for pancreatic cancer using the histoculture drug response assay

The prognosis for patients with pancreatic cancer is extremely poor, as they are resistant to first line chemotherapy. The long-term goal of this study was to identify effective combination chemotherapy for pancreatic cancer using pancreatic cancer surgical specimens in the histoculture drug response assay (HDRA) based on three-dimensional culture of tumour fragments, which maintains nature tumour histology in vitro. From 2015 to 2017, the HDRA was performed with tumour specimens from 52 pancreatic cancer patients from Asan Medical Hospital. First, combination drug regimens showed higher drug efficacy and less patient variation than single drugs. Initially, 5-Fluorouracil(5-FU)/Belotecan/Oxaliplatinum and Tegafur/Gimeracil (TS-1)/Oxaliplatinum/Irinotecan were found to be effective. Second, we were able to correlate the efficacy of some drugs with tumour stage. Third, when designing new combination regimens containing 5-FU or gemcitabine, we could identify more effective drug combinations. This is the first study to demonstrate usefulness of the HDRA for pancreatic cancer. Using this technique, we could identify novel candidate combination drug regimens that should be effective in treating pancreatic cancer.

Pancreatic cancer in Australia: is not it time we address the inequitable resource problem?

The present study reviewed the geographical variations in the delivery of pancreatic cancer therapy and whether this impacts overall survival. The evidence suggests a difference in the accessibility of pancreatic cancer care to patients in rural as compared with urban Australia. While centralization of pancreatic surgery is essential to deliver high quality care to patients, it may be interfering with the ease of access of this form of care to patients in regional areas. Access to chemotherapy in regional Australia is also limited. There is need for a concerted effort to improve the overall care and uptake of medical services to patients in metropolitan and remote Australia with the overarching aim of improving survival and meaningful quality of life.