Distinctive Pathology Associated With Focal Stenosis of the Main Pancreatic Duct Secondary to Remote Trauma: A Long-term Complication of Seat Belt Pancreatitis

The radiologic finding of focal stenosis of the main pancreatic duct is highly suggestive of pancreatic cancer. Even in the absence of a mass lesion, focal duct stenosis can lead to surgical resection of the affected portion of the pancreas. We present four patients with distinctive pathology associated with non-neoplastic focal stenosis of the main pancreatic duct. The pathology included stenosis of the pancreatic duct accompanied by wavy, acellular, serpentine-like fibrosis, chronic inflammation with foreign body-type giant cell reaction, and calcifications. In all cases, the pancreas toward the tail of the gland had obstructive changes including acinar drop-out and interlobular and intralobular fibrosis. Three of the four patients had a remote history of major motor vehicle accidents associated with severe abdominal trauma. These results emphasize that blunt trauma can injure the pancreas and that this injury can result in long-term complications, including focal stenosis of the main pancreatic duct. Pathologists should be aware of the distinct pathology associated with remote trauma and, when the pathology is present, should elicit the appropriate clinical history.

Exploring the Clinical Use of Molecular Profiling of Intrahepatic Cholangiocarcinoma in a Comprehensive Multidisciplinary Clinic

BACKGROUND

Molecular profiling of intrahepatic cholangiocarcinoma (ICC) can detect actionable molecular alterations and guide targeted therapies. We explore the clinical use of molecular profiling of ICC in our comprehensive multidisciplinary clinic.

STUDY DESIGN

Patients with a tissue diagnosis of ICC seen between 2019 and 2023 were identified. A retrospective review was performed to identify their molecular profiles and targeted therapy. The association between the detection of actionable molecular alterations and overall survival (OS) from the first clinic visit date was studied. Patients with an OS of less than 2 months were excluded.

RESULTS

Among 194 patients with ICC, 125 had molecular profiling. Actionable molecular alterations were detected in 56 (45%) patients, including microsatellite instability (n = 3), high tumor mutational burden (>10 muts/mb; n = 5), isocitrate dehydrogenase 1 and 2 mutations (n = 22 and 6, respectively), BRAF V600E mutations (n = 2), phosphatidylinositol-4,5-bisphosphate 3-kinase, catalytic subunit alpha mutations (n = 7), breast cancer 1 and breast cancer 2 mutations (n = 5), mesenchymal epithelial transition amplification (n = 2), fibroblast growth factor receptor 2 and 3 fusions (n = 13), erb-b2 receptor tyrosine kinase 2 overexpression (n = 6), and receptor tyrosine kinase 1 fusion (n = 1). Twenty-one patients received targeted therapies during their treatment course. Survival analysis revealed that for 120 patients with molecular profiling, the detection of an actionable molecular alteration was associated with improved mean OS (34.1 vs 23.6 months, p = 0.008). Among 70 patients with nonmetastatic ICC, the detection of an actionable molecular alteration was associated with improved mean OS (32.1 vs 27.5 months, p = 0.02).

CONCLUSIONS

Actionable molecular alterations were frequently observed in patients with ICC. Detection of actionable alterations was associated with improved OS. The role of targeted therapy needs further exploration in prospective multicenter studies.

Notch Signaling Regulates Immunosuppressive Tumor-Associated Macrophage Function in Pancreatic Cancer

Pancreatic ductal adenocarcinoma (PDA) continues to have a dismal prognosis. The poor survival of patients with PDA has been attributed to a high rate of early metastasis and low efficacy of current therapies, which partly result from its complex immunosuppressive tumor microenvironment. Previous studies from our group and others have shown that tumor-associated macrophages (TAM) are instrumental in maintaining immunosuppression in PDA. Here, we explored the role of Notch signaling, a key regulator of immune response, within the PDA microenvironment. We identified Notch pathway components in multiple immune cell types within human and mouse pancreatic cancer. TAMs, the most abundant immune cell population in the tumor microenvironment, expressed high levels of Notch receptors, with cognate ligands such as JAG1 expressed on tumor epithelial cells, endothelial cells, and fibroblasts. TAMs with activated Notch signaling expressed higher levels of immunosuppressive mediators, suggesting that Notch signaling plays a role in macrophage polarization within the PDA microenvironment. Genetic inhibition of Notch in myeloid cells led to reduced tumor size and decreased macrophage infiltration in an orthotopic PDA model. Combination of pharmacologic Notch inhibition with PD-1 blockade resulted in increased cytotoxic T-cell infiltration, tumor cell apoptosis, and smaller tumor size. Our work implicates macrophage Notch signaling in the establishment of immunosuppression and indicates that targeting the Notch pathway may improve the efficacy of immune-based therapies in patients with PDA.

Detecting Somatic Mutations for Well-Differentiated Pancreatic Neuroendocrine Tumors in Endoscopic Ultrasound-Guided Fine Needle Aspiration with Next-Generation Sequencing

BACKGROUND

Pancreatic neuroendocrine tumors (PanNETs) exhibit heterogenous behavior, whereby some small tumors are aggressive with a propensity for metastasis. Detection of somatic mutations associated with aggressive biology may help with patient stratification and surgical decision-making in patients with well-differentiated PanNETs. Using next-generation sequencing (NGS), we investigated the feasibility of detecting somatic mutations in endoscopic ultrasound-guided, fine-needle aspiration (EUS-FNA) specimens and determining the mutational concordance between the EUS-FNA specimens and the primary tumors.

METHODS

Thirty-eight patients with well-differentiated, nonfunctioning PanNETs were obtained from two tertiary referral centers. Patient demographic characteristics and tumor, clinicopathologic features were collected. Tissue from both the EUS-FNA specimen and the primary tumor was extracted from archival tissue blocks. NGS using a panel of ten genes was performed on both samples.

RESULTS

In our series, the median age was 61.1 years. Tumors were predominantly left-sided (60.5%) and unifocal (94.7%). The median tumor size was 2.2 cm. NGS detected somatic mutations in 29% of primary tumors and 36.8% of EUS-FNA specimens. In primary tumors, DAXX/ATRX mutations were predominantly detected (63.6%). In EUS-FNA specimens, MEN1 mutations were predominantly detected (64.3%). Among non-wild-type specimens, mutational concordance was achieved in 31.6% of cases. In 11 patients with a detectable mutation in the primary tumor, a mutation was detected in the EUS-FNA specimen in 45.5% of cases, with a mutational concordance of 54.5%.

CONCLUSIONS

NGS can detect somatic mutations in EUS-FNA specimens of well-differentiated PanNETs. Efforts to improve detection sensitivity and mutational concordance are required to overcome current technical limitations.

Oncologic resection of pancreatic cancer with isolated liver metastasis: Favorable outcomes in select patients

BACKGROUND

Patients with pancreatic ductal adenocarcinoma (PDAC) and liver metastasis are treated with palliative chemotherapy, whereas similar patients with metastatic colorectal cancer are considered for aggressive surgery.

METHODS

Using an institutional database, PDAC patients undergoing liver resection for isolated metastasis were identified. Their overall survival (OS), treatment factors, and clinicopathological variables associated with survival were also evaluated.

RESULTS

Forty-seven patients underwent curative-intent surgery for metastatic PDAC to the liver between 2000 and 2019. Median OS was 21.9 months from diagnosis. Fourteen patients underwent unplanned resection of radiographically occult liver metastasis during pancreatectomy with median OS of 8.7 months. On the other hand, 29 patients received systemic chemotherapy followed by planned resection; this cohort had the most favorable prognosis following aggressive surgery with median OS being 38.1 months from diagnosis and 24.1 months from surgery. Preoperative chemotherapy (HR = 7.1; p = .002) and moderate to well differentiation of the primary tumor (HR = 3.7; p = .003) were associated with prolonged survival in multivariate analysis, whereas lymph node metastases, response to preoperative therapy, number of liver metastasis, and extent of liver surgery were not.

CONCLUSIONS

In select patients with PDAC and isolated liver metastasis, curative-intent surgery can result in meaningful survival. This aggressive approach seems most beneficial in patients following induction chemotherapy.

Conduits in Vascular Pancreatic Surgery: Analysis of Clinical Outcomes, Operative Techniques, and Graft Performance

OBJECTIVES

We analyze successes and failures of pushing the boundaries in vascular pancreatic surgery to establish safety of conduit reconstructions.

BACKGROUND

Improved systemic control from chemotherapy in pancreatic cancer is increasing the demand for surgical solutions of extensive local vessel involvement, but conduit-specific data are scarce.

METHODS

We identified 63 implanted conduits (41% autologous vessels, 37% allografts, 18% PTFE) in 56 pancreatic resections of highly selected cancer patients between October 2013 and July 2020 from our prospectively maintained database. Assessed parameters were survival, perioperative complications, operative techniques (anatomic and extra-anatomic routes), and conduit patency.

RESULTS

For vascular reconstruction, 25 arterial and 38 venous conduits were utilized during 39 pancreatoduodenectomies, 14 distal pancreatectomies, and 3 total pancreatectomies. The median postoperative survival was 2 years. A Clavien-Dindo grade ≥IIIa complication was apparent in 50% of the patients with a median Comprehensive Complication Index of 29.6. The 90-day mortality in this highly selected cohort was 9%. Causes of mortality were conduit related in 3 patients, late postpancreatectomy hemorrhage in 1 patient, and early liver metastasis in 1 patient. Image-based patency rates of conduits were 66% and 45% at postoperative days 30 and 90, respectively.

CONCLUSIONS

Our perioperative mortality of vascular pancreatic surgery with conduits in the arterial or venous system is 9%. Reconstructions are technically feasible with different anatomic and extra-anatomic strategies, while identifying predictors of early conduit occlusion remains challenging. Optimizing reconstructed arterial and venous hemodynamics in the context of pancreatic malignancy will enable long-term survival in more patients responsive to chemotherapies.

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.

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.

Retrograde Open Celiac Stenting for Ischemic Hepatitis following Pancreaticoduodenectomy

A 74-year-old man with pancreatic cancer had undergone pancreaticoduodenectomy and subsequently developed ischemic hepatitis secondary to high-grade celiac artery stenosis. Celiac antegrade stenting via brachial artery access was unsuccessful, and open antegrade bypass would have required takedown of the pancreatic and/or biliary anastomoses for adequate exposure. Retrograde open celiac stenting was, therefore, successfully performed via the gastroduodenal artery stump. His ischemic hepatitis resolved, and he was ultimately discharged with dual antiplatelet therapy. Computed tomography angiography at 6 months demonstrated a widely patent celiac stent. Retrograde open celiac stenting via the gastroduodenal artery stump is an alternative to open bypass for celiac revascularization not amenable to percutaneous antegrade stenting in patients who have undergone pancreaticoduodenectomy.

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.

Notch signaling regulates immunosuppressive tumor-associated macrophage function in pancreatic cancer

Pancreatic ductal adenocarcinoma (PDA) continues to have a dismal prognosis. The poor survival of patients with PDA has been attributed to a high rate of early metastasis and low efficacy of current therapies, which partly result from its complex immunosuppressive tumor microenvironment. Previous studies from our group and others have shown that tumor-associated macrophages (TAMs) are instrumental in maintaining immunosuppression in PDA. Here, we explored the role of Notch signaling, a key regulator of immune response, within the PDA microenvironment. We identified Notch pathway components in multiple immune cell types within human and mouse pancreatic cancer. TAMs, the most abundant immune cell population in the tumor microenvironment, express high levels of Notch receptors with cognate ligands such as JAG1 expressed on tumor epithelial cells, endothelial cells and fibroblasts. TAMs with activated Notch signaling expressed higher levels of immunosuppressive mediators including arginase 1 (Arg1) suggesting that Notch signaling plays a role in macrophage polarization within the PDA microenvironment. Combination of Notch inhibition with PD-1 blockade resulted in increased cytotoxic T cell infiltration, tumor cell apoptosis, and smaller tumor size. Our work implicates macrophage Notch signaling in the establishment of immunosuppression and indicates that targeting the Notch pathway may improve the efficacy of immune-based therapies in PDA patients.

Surgical Decision-Making in Pancreatic Ductal Adenocarcinoma: Modeling Prognosis Following Pancreatectomy in the Era of Induction and Neoadjuvant Chemotherapy

OBJECTIVE

To develop a predictive model of oncologic outcomes for patients with pancreatic ductal adenocarcinoma (PDAC) undergoing resection after neoadjuvant or induction chemotherapy use.

BACKGROUND

Early recurrence following surgical resection for PDAC is common. The use of neoadjuvant chemotherapy prior to resection may increase the likelihood of long-term systemic disease control. Accurately characterizing an individual's likely oncologic outcome in the perioperative setting remains challenging.

METHODS

Data from patients with PDAC who received chemotherapy prior to pancreatectomy at a single high-volume institution between 2007 and 2018 were captured in a prospectively collected database. Core clinicopathologic data were reviewed for accuracy and survival data were abstracted from the electronic medical record and national databases. Cox-proportional regressions were used to model outcomes and develop an interactive prognostic tool for clinical decision-making.

RESULTS

A total of 581 patients were included with a median overall survival (OS) and recurrence-free survival (RFS) of 29.5 (26.5-32.5) and 16.6 (15.8-17.5) months, respectively. Multivariable analysis demonstrates OS and RFS were associated with type of chemotherapeutic used andthe number of chemotherapy cycles received preoperatively. Additional factors contributing to survival models included: tumor grade, histopathologic response to therapy, nodal status, and administration of adjuvant chemotherapy. The models were validated using an iterative bootstrap method and with randomized cohort splitting. The models were well calibrated with concordance indices of 0.68 and 0.65 for the final OS and RFS models, respectively.

CONCLUSION

We developed an intuitive and dynamic decision-making tool that can be useful in estimating OS, RFS, and location-specific disease recurrence rates. This prognostic tool may add value to patient care in discussing the benefits associated with surgical resection for PDAC.

Postoperative Chemotherapy is Associated with Improved Survival in Patients with Node-Positive Pancreatic Ductal Adenocarcinoma After Neoadjuvant Therapy

BACKGROUND

Postoperative chemotherapy following pancreatic cancer resection is the standard of care. The utility of postoperative chemotherapy for patients who receive neoadjuvant therapy (NAT) is unclear.

METHODS

Patients who underwent pancreatectomy after NAT with FOLFIRINOX or gemcitabine-based chemotherapy for non-metastatic pancreatic adenocarcinoma (2015-2019) were identified. Patients who received less than 2 months of neoadjuvant chemotherapy or died within 90 days from surgery were excluded.

RESULTS

A total of 427 patients (resectable, 22.2%; borderline resectable, 37.9%; locally advanced, 39.8%) were identified with the majority (69.3%) receiving neoadjuvant FOLFIRINOX. Median duration of NAT was 4.1 months. Following resection, postoperative chemotherapy was associated with an improved median overall survival (OS) (28.7 vs. 20.4 months, P = 0.006). Risk-adjusted multivariable modeling showed negative nodal status (N0), favorable pathologic response (College of American Pathologists score 0 & 1), and receipt of postoperative chemotherapy to be independent predictors of improved OS. Regimen, duration, and number of cycles of NAT were not significant predictors. Thirty-four percent (60/176) of node-positive and 50.1% (126/251) of node-negative patients did not receive postoperative chemotherapy due to poor functional status, postoperative complications, and patient preference. Among patients with node-positive disease, postoperative chemotherapy was associated with improved median OS (27.2 vs. 10.5 months, P < 0.001). Among node-negative patients, postoperative chemotherapy was not associated with a survival benefit (median OS, 30.9 vs. 36.9 months; P = 0.406).

CONCLUSION

Although there is no standard NAT regimen for patients with pancreatic cancer, postoperative chemotherapy following NAT and resection appears to be associated with improved OS for patients with node-positive disease.

Precision Medicine in Pancreatic Cancer: Patient-Derived Organoid Pharmacotyping Is a Predictive Biomarker of Clinical Treatment Response

PURPOSE

Patient-derived organoids (PDO) are a promising technology to support precision medicine initiatives for patients with pancreatic ductal adenocarcinoma (PDAC). PDOs may improve clinical next-generation sequencing (NGS) and enable rapid ex vivo chemotherapeutic screening (pharmacotyping).

EXPERIMENTAL DESIGN

PDOs were derived from tissues obtained during surgical resection and endoscopic biopsies and studied with NGS and pharmacotyping. PDO-specific pharmacotype is assessed prospectively as a predictive biomarker of clinical therapeutic response by leveraging data from a randomized controlled clinical trial.

RESULTS

Clinical sequencing pipelines often fail to detect PDAC-associated somatic mutations in surgical specimens that demonstrate a good pathologic response to previously administered chemotherapy. Sequencing the PDOs derived from these surgical specimens, after biomass expansion, improves the detection of somatic mutations and enables quantification of copy number variants. The detection of clinically relevant mutations and structural variants is improved following PDO biomass expansion. On clinical trial, PDOs were derived from biopsies of treatment-naïve patients prior to treatment with FOLFIRINOX (FFX). Ex vivo PDO pharmacotyping with FFX components predicted clinical therapeutic response in these patients with borderline resectable or locally advanced PDAC treated in a neoadjuvant or induction paradigm. PDO pharmacotypes suggesting sensitivity to FFX components were associated with longitudinal declines of tumor marker, carbohydrate-antigen 19-9 (CA-19-9), and favorable RECIST imaging response.

CONCLUSIONS

PDOs established from tissues obtained from patients previously receiving cytotoxic chemotherapies can be accomplished in a clinically certified laboratory. Sequencing PDOs following biomass expansion improves clinical sequencing quality. High in vitro sensitivity to standard-of-care chemotherapeutics predicts good clinical response to systemic chemotherapy in PDAC. See related commentary by Zhang et al., p. 3176.

RAD51B Harbors Germline Mutations Associated With Pancreatic Ductal Adenocarcinoma

PURPOSE

Genetic alterations in many components of the homologous recombination, DNA damage response, and repair (HR-DDR) pathway are involved in the hereditary cancer syndromes, including familial pancreatic cancer. HR-DDR genes beyond BRCA1, BRCA2, ATM, and PALB2 may also mutate and confer the HR-DDR deficiency in pancreatic ductal adenocarcinoma (PDAC).

METHODS

We conducted a study to examine the genetic alterations using a companion diagnostic 15-gene HR-DDR panel in PDACs. HR-DDR gene mutations were identified and characterized by whole-exome sequencing and whole-genome sequencing. Different HR-DDR gene mutations are associated with variable homologous recombination deficiency (HRD) scores.

RESULTS

Eight of 50 PDACs with at least one HR-DDR gene mutation were identified. One tumor with BRCA2 mutations is associated with a high HRD score. However, another tumor with a CHEK2 mutation is associated with a zero HRD score. Notably, four of eight PDACs in this study harbor a RAD51B gene mutation. All four RAD51B gene mutations were germline mutations. However, currently, RAD51B is not the gene panel for germline tests.

CONCLUSION

The finding in this study thus supports including RAD51B in the germline test of HR-DDR pathway genes.

Pathological treatment response has different prognostic implications for pancreatic cancer patients treated with neoadjuvant chemotherapy or chemoradiotherapy

BACKGROUND

Pathological treatment effect of resected pancreatic adenocarcinoma after neoadjuvant therapy has prognostic implications. The impact for patients who received chemotherapy alone or chemoradiotherapy is not well defined.

METHODS

Patients with localized pancreatic adenocarcinoma who had pancreatectomy after neoadjuvant therapy at 3 centers from 2011 to 2017 were retrospectively analyzed. The chemotherapy and chemoradiotherapy groups were evaluated separately.

RESULTS

Of 525 patients, 148 received neoadjuvant chemotherapy and 377 received chemoradiotherapy. The chemoradiotherapy group had a better treatment effect (score 0: 10%, score 1: 30%, score 2: 42%, and score 3: 18%) than the chemotherapy group (score 0: 2%, score 1: 8%, score 2: 35%, and score 3: 55%) (P < .001). Median overall survival was similar between the 2 groups (25.8 vs 26.4 months). Median overall survival for score 0/1, 2, or 3 was 72.2, 38.5, and 20.0 months in the chemotherapy group and 37.9, 24.5, and 19.0 months in the chemoradiotherapy group. Score 2 in the chemotherapy group was associated with better overall survival compared to score 3 (adjusted hazard ratio: 0.49, P = .005), whereas only combined score 0/1 reached significance over score 2 for the chemoradiotherapy group (hazard ratio: 0.63, P = .006).

CONCLUSION

The prognostic significance of pathological treatment effect for localized pancreatic adenocarcinoma differs for patients receiving neoadjuvant chemotherapy or neoadjuvant chemoradiotherapy.

The Impact of the COVID-19 Pandemic on Multidisciplinary Clinics: A High-Volume Pancreatic Cancer Center Experience

The unprecedented impact of the Sars-CoV-2 pandemic (COVID-19) has strained the healthcare system worldwide. The impact is even more profound on diseases requiring timely complex multidisciplinary care such as pancreatic cancer. Multidisciplinary care teams have been affected significantly in multiple ways as healthcare teams collectively acclimate to significant space limitations and shortages of personnel and supplies. As a result, many patients are now receiving suboptimal remote imaging for diagnosis, staging, and surgical planning for pancreatic cancer. In addition, the lack of face-to-face interactions between the physician and patient and between multidisciplinary teams has challenged patient safety, research investigations, and house staff education. In this study, we discuss how the COVID-19 pandemic has transformed our high-volume pancreatic multidisciplinary clinic, the unique challenges faced, as well as the potential benefits that have arisen out of this situation. We also reflect on its implications for the future during and beyond the pandemic as we anticipate a hybrid model that includes a component of virtual multidisciplinary clinics as a means to provide accessible world-class healthcare for patients who require complex oncologic management.

Technical Standards for Cancer Surgery: Improving Patient Care through Synoptic Operative Reporting

The Operative Standards for Cancer Surgery manuals define critical elements of optimal cancer surgery based on data and expert opinion. These key aspects of commonly performed cancer operations define technical standards that can be used as a quality assurance tool for practicing surgical oncologists and as an educational tool for trainees. This article provides background on these operative standards and their subsequent integration into synoptic operative report templates. With the goal of codifying the most important aspects of surgical oncology care to elevate and harmonize cancer care, the American College of Surgeons Cancer Programs has developed comprehensive synoptic operative reports. Synoptic operative reports are structured so that key data elements are recorded in a standardized format with prespecified terminology. In contrast to the narrative or structured operative reports frequently used by surgeons, these synoptic operative reports improve semantic clarity, provide uniform fields for abstraction, and facilitate passive data collection and real-time analytics while delivering key information for downstream multidisciplinary patient care. In this way, the synoptic operative report is a key component of a comprehensive effort to elevate the quality of cancer care nationally.

Anatomic Criteria Determine Resectability in Locally Advanced Pancreatic Cancer

BACKGROUND

The introduction of multi-agent chemotherapy and radiation therapy has facilitated potential resection with curative intent in selected locally advanced pancreatic cancer (LAPC) patients with excellent outcomes. Nevertheless, there remains a remarkable lack of consensus on the management of LAPC. We sought to describe the outcomes of patients with LAPC and objectively define the multidisciplinary selection process for operative exploration based on anatomical factors.

METHODS

Consecutive patients with LAPC were evaluated for pancreatic surgery in the multidisciplinary clinic of a high-volume institution, between 2013 and 2018. Prospective stratification (LAPC-1, LAPC-2, and LAPC-3), based on the involvement of regional anatomical structures, was performed at the time of presentation prior to the initiation of treatment. Resection rates and patient outcomes were evaluated and correlated with the initial anatomic stratification system.

RESULTS

Overall, 415 patients with LAPC were included in the study, of whom 84 (20%) were successfully resected, with a median overall survival of 35.3 months. The likelihood of operative exploration was associated with the pretreatment anatomic LAPC score, with a resection rate of 49% in patients classified as LAPC-1, 32% in LAPC-2, and 11% in LAPC-3 (p < 0.001). Resected patients with improvement of the LAPC score at the time of exploration had significantly longer median overall survival compared with those with no change or progression of LAPC score (60.7 vs. 29.8 months, p = 0.006).

CONCLUSIONS

Selected patients with LAPC can undergo curative-intent surgery with excellent outcomes. The proposed Johns Hopkins anatomic LAPC score provides an objective system to anticipate the probability of eventual surgical resection after induction therapy.

Implantation of a neoantigen-targeted hydrogel vaccine prevents recurrence of pancreatic adenocarcinoma after incomplete resection

Tumor involvement of major vascular structures limits surgical options in pancreatic adenocarcinoma (PDAC), which in turn limits opportunities for cure. Despite advances in locoregional approaches, there is currently no role for incomplete resection. This study evaluated a gelatinized neoantigen-targeted vaccine applied to a grossly positive resection margin in preventing local recurrence. Incomplete surgical resection was performed in mice bearing syngeneic flank Panc02 tumors, leaving a 1 mm rim adherent to the muscle bed. A previously validated vaccine consisting of neoantigen peptides, a stimulator of interferon genes (STING) agonist and AddaVax^TM (termed PancVax) was embedded in a hyaluronic acid hydrogel and applied to the tumor bed. Tumor remnants, regional lymph nodes, and spleens were analyzed using histology, flow cytometry, gene expression profiling, and ELISPOT assays. The immune microenvironment at the tumor margin after surgery alone was characterized by a transient influx of myeloid-derived suppressor cells (MDSCs), prolonged neutrophil influx, and near complete loss of cytotoxic T cells. Application of PancVax gel was associated with enhanced T cell activation in the draining lymph node and expansion of neoantigen-specific T cells in the spleen. Mice implanted with PancVax gel demonstrated no evidence of residual tumor at two weeks postoperatively and healed incisions at two months postoperatively without local recurrence. In summary, application of PancVax gel at a grossly positive tumor margin led to systemic expansion of neoantigen-specific T cells and effectively prevented local recurrence. These findings support further work into locoregional adjuncts to immune modulation in PDAC.

Neoadjuvant Cabozantinib and Nivolumab Converts Locally Advanced HCC into Resectable Disease with Enhanced Antitumor Immunity

A potentially curative hepatic resection is the optimal treatment for hepatocellular carcinoma (HCC), but most patients are not candidates for resection and most resected HCCs eventually recur. Until recently, neoadjuvant systemic therapy for HCC has been limited by a lack of effective systemic agents. Here, in a single arm phase 1b study, we evaluated the feasibility of neoadjuvant cabozantinib and nivolumab in patients with HCC including patients outside of traditional resection criteria (NCT03299946). Of 15 patients enrolled, 12 (80%) underwent successful margin negative resection, and 5/12 (42%) patients had major pathologic responses. In-depth biospecimen profiling demonstrated an enrichment in T effector cells, as well as tertiary lymphoid structures, CD138+ plasma cells, and a distinct spatial arrangement of B cells in responders as compared to non-responders, indicating an orchestrated B-cell contribution to antitumor immunity in HCC.

Protein synthesis inhibitor omacetaxine is effective against hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the sixth most common and the fourth most deadly cancer worldwide. The development cost of new therapeutics is a major limitation in patient outcomes. Importantly, there is a paucity of preclinical HCC models in which to test new small molecules. Herein, we implemented potentially novel patient-derived organoid (PDO) and patient-derived xenografts (PDX) strategies for high-throughput drug screening. Omacetaxine, an FDA-approved drug for chronic myelogenous leukemia (CML), was found to be a top effective small molecule in HCC PDOs. Next, omacetaxine was tested against a larger cohort of 40 human HCC PDOs. Serial dilution experiments demonstrated that omacetaxine is effective at low (nanomolar) concentrations. Mechanistic studies established that omacetaxine inhibits global protein synthesis, with a disproportionate effect on short–half-life proteins. High-throughput expression screening identified molecular targets for omacetaxine, including key oncogenes, such as PLK1. In conclusion, by using an innovative strategy, we report — for the first time to our knowledge — the effectiveness of omacetaxine in HCC. In addition, we elucidate key mechanisms of omacetaxine action. Finally, we provide a proof-of-principle basis for future studies applying drug screening PDOs sequenced with candidate validation in PDX models. Clinical trials could be considered to evaluate omacetaxine in patients with HCC.

Defining a minimum number of examined lymph nodes improves the prognostic value of lymphadenectomy in pancreas ductal adenocarcinoma

BACKGROUND

Lymph node (LN) metastasis is associated with decreased survival following resection for pancreatic ductal adenocarcinoma (PDAC). In N0 disease, increasing total evaluated LN (ELN) correlates with improved outcomes suggesting patients may be understaged when LNs are undersampled. We aim to assess the optimal number of examined lymph nodes (ELN) following pancreatectomy.

METHODS

Data from 1837 patients undergoing surgery were prospectively collected. The binomial probability law was utilized to analyze the minimum number of examined LNs (minELN) and accurately characterize each histopathologic stage. LN ratio (LNR) was compared to American Joint Committee on Cancer (AJCC) guidelines.

RESULTS

As ELN total increased, the likelihood of finding node positive disease increased. An evaluation based upon the binomial probability law suggested an optimal minELN of 12 for accurate AJCC N staging. As the number of ELNs increased, the discriminatory capacity of alternative strategies to characterize LN disease exceeded that offered by AJCC N stage.

CONCLUSION

This is the first study dedicated to optimizing histopathologic staging in PDAC using models of minELN informed by the binomial probability law. This study highlights two separate cutoffs for ELNs depending upon prognostic goal and validates that 12 LNs are adequate to determine AJCC N stage for the majority of patients.

Autoimmune Pancreatitis: A Critical Analysis of the Surgical Experience in an Era of Modern Diagnostics

OBJECTIVE

The aim of this study was to critically analyze the surgical experience of managing autoimmune pancreatitis (AIP) in an era of modern diagnostics and compare these patients with those who were managed conservatively.

METHODS

Two prospectively maintained databases were used to retrospectively identify patients with AIP who were either managed conservatively or underwent pancreatectomy.

RESULTS

Eighty-eight patients were included in the study, of which 56 (63.6%) underwent resection and 32 (36.4%) were managed conservatively. Patients who underwent resection were more likely to present with jaundice (64.3% vs 18.1%, P < 0.001) and weight loss (53.6% vs 15.6%, P = 0.005). The cohort who underwent resection had a significantly higher median carbohydrate antigen 19-9 (40.0 vs 18.6 U/mL, P = 0.034) and was less likely to have elevated immunoglobulin G4 (26.1% vs 50.0%, P < 0.001). The most frequent initial diagnosis in the cohort who underwent resection was ductal adenocarcinoma (82.1%). Nine patients (28.1%) in the conservatively managed cohort experienced AIP relapse compared with 6 patients (10.7%) in the cohort who underwent resection.

CONCLUSIONS

The most frequent reason for surgical resection of AIP is concern for malignancy. Carbohydrate antigen 19-9 elevations were more common than immunoglobulin G4 in our cohort, suggesting that this laboratory profile is suboptimal for this population.

Challenges of the current precision medicine approach for pancreatic cancer: A single institution experience between 2013 and 2017

Recent research on genomic profiling of pancreatic ductal adenocarcinoma (PDAC) has identified many potentially actionable alterations. However, the feasibility of using genomic profiling to guide routine clinical decision making for PDAC patients remains unclear. We retrospectively reviewed PDAC patients between October 2013 and December 2017, who underwent treatment at the Johns Hopkins Hospital and had clinical tumor next-generation sequencing (NGS) through commercial resources. Ninety-two patients with 93 tumors tested were included. Forty-eight (52%) patients had potentially curative surgeries. The median time from the tissue available to the NGS testing ordered was 229 days (interquartile range 62-415). A total of three (3%) patients had matched targeted therapies based on genomic profiling results. Genomic profiling guided personalized treatment for PDAC patients is feasible, but the percentage of patients who receive targeted therapy is low. The main challenges are ordering NGS testing early in the clinical course of the disease and the limited evidence of using a targeted approach in these patients. A real-time department level genomic testing ordering system in combination with an evidence-based flagging system for potentially actionable alterations could help address these shortcomings.

Impact of Margin Status on Survival in Patients with Pancreatic Ductal Adenocarcinoma Receiving Neoadjuvant Chemotherapy

BACKGROUND

Historically, a positive margin after pancreatectomy for pancreatic ductal adenocarcinoma (PDAC) was associated with decreased survival. In an era when neoadjuvant chemotherapy (NAC) is being used frequently, the prognostic significance of margin status is unclear.

STUDY DESIGN

Patients with localized PDAC who received NAC and underwent pancreatectomy from 2011 to 2018 were identified from a single-institution database. Patients with fewer than 2 months of NAC, R2 resection, or fewer than 90 days of follow-up were excluded. A positive margin included tumors within 1 mm of the surgical margin.

RESULTS

Four hundred and sixty-eight patients met inclusion criteria. Median age was 65 years and 53% were female. Preoperative clinical staging demonstrated that most had locally advanced (n = 222 [47%]) or borderline resectable (n = 172 [37%]) disease. Median follow-up was 18.5 months (interquartile range 10.6 to 30.0 months). Median duration of NAC was 119 days (interquartile range 87 to 168 days). FOLFIRINOX was first-line therapy for 67%, and 73% received neoadjuvant radiotherapy. Most underwent pancreaticoduodenectomy (69%). Forty percent were node-positive and 80% had an R0 resection. Fifty-six percent received at least 1 cycle of adjuvant therapy. Median overall survival and recurrence-free survival were 22.0 months (95% CI, 19.4 to 25.1 months) and 11.0 months (95% CI, 10.0 to 12.1 months). On multivariate analysis, margin status was not a significant predictor of overall survival or recurrence-free survival. Factors associated with overall survival included clinical stage, duration of NAC, nodal status, histopathologic treatment response score, and receipt of adjuvant chemotherapy.

CONCLUSIONS

Microscopic margin positivity is not associated with recurrence and survival in localized PDAC patients resected after treatment with NAC. Aggressive surgical extirpation in high-volume centers should be considered in selected patients after extensive NAC.

Rapidly progressive metastatic cholangiocarcinoma in a postpartum patient with cystic fibrosis: a case report

BACKGROUND

Cholangiocarcinoma is a rare gastrointestinal malignancy that arises within the intrahepatic, perihilar, and/or extrahepatic bile ducts. Individuals with cystic fibrosis are at increased risk for gastrointestinal malignancies. The most common gastrointestinal malignancy in cystic fibrosis is colon cancer, but other gastrointestinal malignancies also occur at greater rates than the general population.

CASE PRESENTATION

We present a case of a rapidly progressive metastatic intrahepatic cholangiocarcinoma in an individual with cystic fibrosis who was 5 months postpartum, incidentally found while undergoing a lung transplantation evaluation.

CONCLUSION

A heightened clinical awareness of gastrointestinal malignancies, beyond colon cancer, in individuals with cystic fibrosis is warranted. It remains unclear if pregnancy is an additional risk factor for gastrointestinal malignancies in cystic fibrosis.

Duodenal, ampullary, and pancreatic neuroendocrine tumors: Oncologic outcomes are driven by tumor biology and tissue of origin

BACKGROUND

Periampullary neuroendocrine tumors (NETs) arise from the duodenum, ampulla, and periampullary pancreas. Duodenal and ampullary NETs are rare and may have distinct biologic behavior from pancreatic NETs (P-NETs). We examined the outcomes of these entities.

METHODS

An institutional database was queried for patients undergoing resection for pancreatic head, duodenal, or ampullary NETs from 2000 to 2018. Patients with MEN1 syndrome or follow up less than 12 months were excluded.

RESULTS

Three hundred and ten patients were identified. Tumor locations were ampulla (n = 15), duodenum (n = 35) and pancreas (n = 260). Median follow-up and recurrence-free survival (RFS) were 60.9 (interquartile range [IQR]: 34.8-99.3) and 171.7 (IQR: 84.0-NR) months. Clinicopathologic data and survival outcomes were similar for duodenal and ampullary NETs (RFS: p = .347 and overall survival [OS]: p = .246) and were combined into an intestinal subtype (IS) group. There were no differences in OS or RFS when comparing IS-NET and P-NET. On multivariate analysis, tissue of origin was not associated with risk of recurrence. The current American Joint Committee on Cancer staging guidelines, which account for origin tissue, were predictive of outcomes for all subtypes.

CONCLUSION

Tissue of origin does not appear to impact long-term outcomes when comparing IS-NETs and P-NETs. The AJCC staging system offers good discriminatory capacity in the context of the tissue type.

An Aggressive Approach to Locally Confined Pancreatic Cancer: Defining Surgical and Oncologic Outcomes Unique to Pancreatectomy with Celiac Axis Resection (DP-CAR)

Background:

Modern chemotherapeutics have led to improved systemic disease control for patients with locally advanced pancreatic cancer (LAPC). Surgical strategies such as distal pancreatectomy with celiac axis resection (DP-CAR) are increasingly entertained. Herein we review procedure specific outcomes and assess biologic rationale for DP-CAR.

Methods:

A prospectively maintained single-institution database of all pancreatectomies was queried for patients undergoing DP-CAR. We excluded all patients for whom complete data were not available and those who were not treated with contemporary multi-agent therapy. Data was supplemented with dedicated chart review and outreach for long-term oncologic outcomes.

Results:

Fifty-four patients underwent DP-CAR between 2008–2018. The median age was 62.7 years. 98% received induction chemotherapy. Arterial reconstruction was performed in 17% and concomitant visceral resection in 30%. R0 resection rate was 87%. Postoperative complications were common (43%) with chyle leak being the most frequent (17%). Length of stay was 8 days, readmission occurred in one-third, and ninety-day mortality was 2%. Disease recurrence occurred in 74% during a median follow up of 17.4 months. Median recurrence-free (RFS) and overall survival (OS) were 9 and 25 months, respectively.

Conclusions:

Following modern induction paradigms, DP-CAR can be performed with low mortality, manageable morbidity, and excellent rates of margin-negative resection in high volume settings. The profile of complications of DP-CAR is distinct from pancreaticoduodenectomy and simple distal pancreatectomy. OS and RFS are similar to those undergoing resection of borderline resectable and resectable disease. Improved systemic disease control will likely lead to increasing utilization of aggressive surgical approaches to LAPC.

Periadventitial dissection of the superior mesenteric artery for locally advanced pancreatic cancer: Surgical planning with the "halo sign" and "string sign"

Most patients diagnosed with pancreatic cancer are classified as nonoperative candidates based on the contemporary guidelines of resectability. The advent of more potent control of systemic disease using neoadjuvant chemotherapy has enabled more aggressive operative interventions. In our multidisciplinary practice, patients with Stage III, locally advanced pancreatic cancer and superior mesenteric artery (SMA) encasement are now carefully triaged with high quality, preoperative imaging to determine if they can be considered candidates for operative resection with periadventitial dissection of the SMA. Patients displaying a "halo sign," where the encased SMA remains fully patent and free from arterial invasion, are now candidates for SMA periadventitial dissection. This procedure involves the surgical stripping of the infiltrated neurolymphatic tissue off the SMA leaving behind a bare "skeletonized artery." Alternatively, the "string sign" involving the SMA confers a more likely case of arterial invasion, where a complete oncologic resection cannot be achieved successfully. This method of patient selection in case of SMA involvement abandons the traditional metrics of circumferential degrees of the arterial encasement to guide surgical decisions. Our institutional approach has allowed us to meaningfully expand our operative methods of resection with the potential for improved longitudinal outcomes to pancreatic cancer patients who were deprived historically from the more effective and possibly curative treatment.

Mesoportal bypass, interposition graft, and mesocaval shunt: Surgical strategies to overcome superior mesenteric vein involvement in pancreatic cancer

BACKGROUND

In pancreatic cancer, extensive tumor involvement of the mesenteric venous system poses formidable challenges to operative resection. Such involvement can result from cavernous collateral veins leading to increased intraoperative blood loss or long-segment vascular defects of not only just the superior mesenteric vein but also even jejunal/ileal branches. Strategies to facilitate margin-free resection and safe vascular reconstruction in pancreatic surgery are important, particularly because systemic control of the tumor is improving with multi-agent chemotherapy regimens.

METHODS

We describe a systematic, multidisciplinary assessment for patients with pancreatic cancer that involves the superior mesenteric vein, as well as the preoperative planning of those undergoing operative resection. In addition, detailed descriptions of operative approaches and technical strategies, which evolved with increasing experience at a high-volume center, are presented.

RESULTS

For the preoperative evaluation of tumor-free, vascular locations for potential reconstruction and collateralization, computed tomographic imaging with high-resolution of vascular structures (used with 3-dimensional or cinematic rendering) allows a precise calibration of radiographic data with intraoperative findings. From an operative perspective, we identified 5 potential strategies to consider for resection: collateral preservation, mesoportal bypass (preresection), mesoportal interposition graft (postresection), mesocaval shunt, and various combinations of these strategies. Many of these techniques use interposition grafts, making it essential to assess autologous veins (preferred conduit for reconstruction) or to prepare cryopreserved vascular allografts (an alternative conduit, which must be thawed and should be matched for size and blood type).

CONCLUSION

Herein we share operative strategies to overcome involvement of the superior mesenteric vein in pancreatic cancer. Improvements in preoperative planning and operative technique can address common barriers to resection with curative intent.

Pancreatic circulating tumor cell detection by targeted single-cell next-generation sequencing

BACKGROUND AND AIMS

Single-cell next-generation sequencing (scNGS) technology has been widely used in genomic profiling, which relies on whole-genome amplification (WGA). However, WGA introduces errors and is especially less accurate when applied to single nucleotide variant (SNV) analysis. Targeted scNGS for SNV without WGA has not been described. We aimed to develop a method to detect circulating tumor cells (CTCs) with DNA SNVs.

METHODS

We tested this targeted scNGS method with three driver mutant genes (KRAS/TP53/SMAD4) on one pancreatic cancer cell line AsPC-1 and then applied it to patients with metastatic PDAC for the validation.

RESULTS

All single-cell of AsPC-1 and spiked-in AsPC-1 cells in healthy donor blood, which were isolated by the filtration with size or by flow cytometry, were detected by targeted scNGS method. All blood samples from six patients with metastatic PDAC, for the validation of target scNGS method, showed CTCs with SNVs of KRAS/TP53/SMAD4 and the positive confirmation of immunofluorescent stainings with Pan-CK/Vimentin/CD45. Four patients with early stage disease, one patient with benign pancreatic cyst and a healthy control sample all showed concordant results between targeted scNGS and CTC enumeration.

CONCLUSIONS

The novel technique of targeted scNGS for SNV analysis, without pre-amplification, is a promising method for identifying and characterizing circulating tumor cells.

Abstract LB-011: Patient-derived organoids may facilitate precision medicine in pancreatic cancer: Demonstrating feasibility in the context of a multi-center clinical trial

Background: Systemic disease control is the principle driver of prognosis in patients with pancreatic cancer (PDAC). Currently, there are no predictive biomarkers of clinical response to guide selection of an optimal treatment approach. Our work explores the logistics and feasibility of generating patient tumor-derived models to serve as biomarkers. Methods: Patients with borderline resectable or locally advanced PDAC enrolled to participate in a multi-institutional prospective, randomized, trial were eligible. Pretreatment core needle biopsies from diagnostic endoscopy were shipped via commercial post to a centralized organoid laboratory. Patient-specific organoids (PDO) were established as previously described by our group. Putative predictive biomarkers of clinical treatment response, including whole-exome sequencing (WES), RNA-sequencing, and pharmacotyping (chemotherapeutic sensitivity testing) were performed prospectively. Putative predictive biomarkers will be compared to clinical outcomes when approved by the trial's Data Safety Monitoring Board. Results: Approximately 40% (42/98) of patients participated in tissue acquisition for organoid development. Culture maturation can be described in three relevant phases: establishment, expansion, and characterization. The establishment phase describes the emergence of viable ductal organoid development in the setting of a culture being cleared of other components of the tumor microenvironment. During these first 3-5 passages, there are numerous potential pitfalls, including technical and logistical challenges. Out of 42, 26 (62%) PDOs were successfully established. Notably, the establishment phase appears to be an area of the greatest improvement, as the rates of successful establishment improve while the collaborative team builds experience. Expansion involves biomass accumulation in clean culture. Of those that succeeded in establishment, 77% (20/26) entered in expansion phase. We can currently report 15 PDOs having reached the characterization phase (WES, RNA-seq with subtyping, and/or pharmacotyping). Based on RNA expression profile, 10/14 were classified as classical and 4 as basal-like subtype. Mean time to pharmacotyping was 179 days. The PDOs showed a variable population distribution of sensitivity to standard-of-care chemotherapeutics (gemcitabine, paclitaxel, irinotecan, 5-FU, oxaliplatin). Conclusions: Developing a living organoid biobank from PDAC biopsies in a multi-center trial setting is a tractable approach in precision medicine initiatives. Amongst a collaborative team of physician scientists, the establishment phase is critical. PDOs from pre-treatment biopsies can be individually characterized within a clinically relevant time frame and unique tumor-specific ex vivo-derived therapeutic sensitivities can be assessed.

Citation Format: Toni T. Seppälä, Jacquelyn W. Zimmerman, Noah Rozich, Alex Blair, Ammar Javed, John L. Cameron, William R. Burns, Jin He, David Tuveson, Christopher L. Wolfgang, David P. Ryan, Alec Kimmelman, Joseph M. Herman, Wells Messersmith, Theodore S. Hong, David T. Ting, Richard Andrew Burkhart. Patient-derived organoids may facilitate precision medicine in pancreatic cancer: Demonstrating feasibility in the context of a multi-center clinical trial [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr LB-011.

Validation of the American Joint Commission on Cancer (AJCC) 8th Edition Staging System for Patients with Pancreatic Adenocarcinoma: A Surveillance, Epidemiology and End Results (SEER) Analysis

BACKGROUND

The 8th edition of the AJCC staging system for pancreatic cancer incorporated several significant changes. This study sought to evaluate this staging system and assess its strengths and weaknesses relative to the 7th edition AJCC staging system.

METHODS

Using the Surveillance, Epidemiology and End Results (SEER) database (2004-2013), 8960 patients undergoing surgical resection for non-metastatic pancreatic adenocarcinoma were identified. Overall survival was estimated using the Kaplan-Meier method and compared using log-rank tests. Concordance indices (c-index) were calculated to evaluate the discriminatory power of both staging systems. The Cox proportional hazards model was used to determine the impact of T and N classification on overall survival.

RESULTS

The c-index for the AJCC 8th staging system [0.60; 95% confidence interval (CI), 0.59-0.61] was comparable with that for the 7th edition AJCC staging system (0.59; 95% CI, 0.58-0.60). Stratified analyses for each N classification system demonstrated a diminishing impact of T classification on overall survival with increasing nodal involvement. The corresponding c-indices were 0.58 (95% CI, 0.55-0.60) for N0, 0.53 (95% CI, 0.51-0.55) for N1, and 0.53 (95% CI, 0.50-0.56) for N2 classification.

CONCLUSION

This is the first large-scale validation of the AJCC 8th edition staging system for pancreatic cancer. The revised system provides discrimination similar to that of the 7th-edition system. However, the 8th-edition system allows for finer stratification of patients with resected tumors according to extent of nodal involvement.

A novel chimeric antigen receptor against prostate stem cell antigen mediates tumor destruction in a humanized mouse model of pancreatic cancer

Despite advances in the understanding of its molecular pathophysiology, pancreatic cancer remains largely incurable, highlighting the need for novel therapies. We developed a chimeric antigen receptor (CAR) specific for prostate stem cell antigen (PSCA), a glycoprotein that is overexpressed in pancreatic cancer starting at early stages of malignant transformation. To optimize the CAR design, we used antigen-recognition domains derived from mouse or human antibodies, and intracellular signaling domains containing one or two T cell costimulatory elements, in addition to CD3zeta. Comparing multiple constructs established that the CAR based on human monoclonal antibody Ha1-4.117 had the greatest reactivity in vitro. To further analyze this CAR, we developed a human pancreatic cancer xenograft model and adoptively transferred CAR-engineered T cells into animals with established tumors. CAR-engineered human lymphocytes induced significant antitumor activity, and unlike what has been described for other CARs, a second-generation CAR (containing CD28 cosignaling domain) induced a more potent antitumor effect than a third-generation CAR (containing CD28 and 41BB cosignaling domains). While our results provide evidence to support PSCA as a target antigen for CAR-based immunotherapy of pancreatic cancer, the expression of PSCA on selected normal tissues could be a source of limiting toxicity.

Review of the impact of presbyopia on quality of life in the developing and developed world

PURPOSE

To examine the public health impact of presbyopia regarding its effect on quality of life (QoL) and society in both the developed and developing worlds.

METHODS

A database was created from articles found on PubMed, the Cochrane Library and Science Direct using the following search terms: presbyopia, QoL, accommodation, impact, cost, prevention, treatment and public health. Articles were accepted into the database if they addressed presbyopia and public health.

RESULTS

This study showed in the developed world presbyopic subjects treated with reading glasses suffered a reduction in QoL parameters compared with those who were younger and emmetropic. A small minority of subjects were assessed to be a candidate for additional non-spectacle treatment measures. In undeveloped areas, the manifestations of presbyopia were similar to the developed world in symptoms, age and reduced QoL. However, there was inadequate treatment of this condition, even with reading glasses. The availability of reading glasses ranged from 6 to 45%. Activities of daily living could not be accomplished as easily without near correction of reading. Reasons described for the lack of correction included: lack of access to medical care, poor awareness of decreased near vision, lack of motivation and cost. Overall scant data exist regarding presbyopia and its impact and how treatment affects QoL.

CONCLUSIONS

This review suggests that the effect of presbyopia and its treatments on QoL remain poorly described and incompletely treated, especially in developing areas of the world.

Multiple chimeric antigen receptors successfully target chondroitin sulfate proteoglycan 4 in several different cancer histologies and cancer stem cells

Background

The development of immunotherapy has led to significant progress in the treatment of metastatic cancer, including the development of genetic engineering technologies that redirect lymphocytes to recognize and target a wide variety of tumor antigens. Chimeric antigen receptors (CARs) are hybrid proteins combining antibody recognition domains linked to T cell signaling elements. Clinical trials of CAR-transduced peripheral blood lymphocytes (PBL) have induced remission of both solid organ and hematologic malignancies. Chondroitin sulfate proteoglycan 4 (CSPG4) is a promising target antigen that is overexpressed in multiple cancer histologies including melanoma, triple-negative breast cancer, glioblastoma, mesothelioma and sarcoma.

Methods

CSPG4 expression in cancer cell lines was assayed using flow cytometry (FACS) and reverse-transcription PCR (RT-PCR). Immunohistochemistry was utilized to assay resected melanomas and normal human tissues (n = 30) for CSPG4 expression and a reverse-phase protein array comprising 94 normal tissue samples was also interrogated for CSPG4 expression. CARs were successfully constructed from multiple murine antibodies (225.28S, TP41.2, 149.53) using second generation (CD28.CD3ζ) signaling domains. CAR sequences were cloned into a gamma-retroviral vector with subsequent successful production of retroviral supernatant and PBL transduction. CAR efficacy was assayed by cytokine release and cytolysis following coculture with target cell lines. Additionally, glioblastoma stem cells were generated from resected human tumors, and CSPG4 expression was determined by RT-PCR and FACS.

Results

Immunohistochemistry demonstrated prominent CSPG4 expression in melanoma tumors, but failed to demonstrate expression in any of the 30 normal human tissues studied. Two of 94 normal tissue protein lysates were positive by protein array. CAR constructs demonstrated cytokine secretion and cytolytic function after co-culture with tumor cell lines from multiple different histologies, including melanoma, breast cancer, mesothelioma, glioblastoma and osteosarcoma. Furthermore, we report for the first time that CSPG4 is expressed on glioblastoma cancer stem cells (GSC) and demonstrate that anti-CSPG4 CAR-transduced T cells recognize and kill these GSC.

Conclusions

The functionality of multiple different CARs, with the widespread expression of CSPG4 on multiple malignancies, suggests that CSPG4 may be an attractive candidate tumor antigen for CAR-based immunotherapies using appropriate technology to limit possible off-tumor toxicity.

Cell surface lactate receptor GPR81 is crucial for cancer cell survival

The mechanisms that allow cancer cells to adapt to the typical tumor microenvironment of low oxygen and glucose and high lactate are not well understood. GPR81 is a lactate receptor recently identified in adipose and muscle cells that has not been investigated in cancer. In the current study, we examined GPR81 expression and function in cancer cells. We found that GPR81 was present in colon, breast, lung, hepatocellular, salivary gland, cervical, and pancreatic carcinoma cell lines. Examination of tumors resected from patients with pancreatic cancer indicated that 94% (148 of 158) expressed high levels of GPR81. Functionally, we observed that the reduction of GPR81 levels using shRNA-mediated silencing had little effect on pancreatic cancer cells cultured in high glucose, but led to the rapid death of cancer cells cultured in conditions of low glucose supplemented with lactate. We also observed that lactate addition to culture media induced the expression of genes involved in lactate metabolism, including monocarboxylase transporters in control, but not in GPR81-silenced cells. In vivo, GPR81 expression levels correlated with the rate of pancreatic cancer tumor growth and metastasis. Cells in which GPR81 was silenced showed a dramatic decrease in growth and metastasis. Implantation of cancer cells in vivo was also observed to lead to greatly elevated levels of GPR81. These data support that GPR81 is important for cancer cell regulation of lactate transport mechanisms. Furthermore, lactate transport is important for the survival of cancer cells in the tumor microenvironment. Cancer Res; 74(18); 5301-10. ©2014 AACR.

Neuroendocrine pancreatic tumors: guidelines for management and update

Pancreatic neuroendocrine tumors (PanNETs) are a diverse group of rare neoplasms. Commonly referred to as islet cell tumors, PanNETs are classified as functional or nonfunctional depending on their production of specific pancreatic endocrine hormones (e.g. insulin, gastrin, glucagon, and others) and association with the resultant clinical syndromes. While most PanNETs are sporadic, syndromic patients, in particular those with multiple endocrine neoplasia type 1 (MEN-1) and von Hippel Lindau (VHL), are at increased risk of developing these tumors. Recent investigations of patients with sporadic and syndromic PanNETs have elucidated critical pathways in tumor development, such as mammalian target of rapamycin (mTOR) signaling and its downstream growth factors such as vascular endothelial growth factor (VEGF). Prognosis ranges from favorable for localized, low-grade neoplasms to poor for advanced, high-grade tumors. Regardless of the stage at presentation, surgery is the first-line therapy for patients with disease amenable to surgical resection. We favor formal pancreatectomy with conventional lymph node sampling for the vast majority of patients, either through open or laparoscopic techniques. Those with insulinomas, however, may be candidates for enucleation. Cytoreductive surgery is also recommended for patients with locoregional recurrences or hepatic metastases. Regional adjuvants such as radiofrequency ablation (RFA), transarterial chemoembolization (TACE), and others are often employed in an attempt to palliate symptoms and prolong survival. Unfortunately, cytotoxic chemotherapy has been largely ineffective in treating patients with PanNETs. The somatostatin analogue octreotide, however, has been effective in palliating symptoms and slowing the progression of disease. Other promising systemic agents, including sunitinib and everolimus, have targeted critical PanNET signaling pathways. In summary, surgery remains the principal therapeutic strategy for patients with PanNETs, but continued research may identify more robust systemic therapies for those with advanced disease.

The position of the AUG start codon in MFG-based γ-retroviral vectors has a dramatic effect on translation-dependent protein expression

BACKGROUND

In the past three decades, much advancement has been made in γ-retroviral vector mediated gene transfer. One widely used vector design is based on the MFG vector, which uses the Moloney murine leukemia virus (MoMLV) transcriptional unit with extended packaging signals and insertion of the native MoMLV envelope splice acceptor region immediate 5' to the gene of interest inserted at an NcoI restriction site, which contains a translation start codon. Little is known about the impact of variations in start codon location within MFG-based vectors on protein expression.

METHODS

To evaluate variation in start condo placement, a gene encoding a T-cell receptor (TCR) was cloned into an MFG-based vector and site-directed mutagenesis was used to move the gene away from the splice acceptor, as well as alter the frame with respect to the upstream start codon. Kozak consensus sequences were also added to the gene in an attempt to improve translation.

RESULTS

Protein expression as measured by TCR surface expression and biological activity was substantially reduced when the gene was placed downstream and out-of-frame with the NcoI start codon. Expression was reestablished by mutation of the upstream start site, although at a reduced level. These findings were repeated with two other genes, a dominant negative TGFβRII and the reporter protein dEGFP.

CONCLUSIONS

These finding emphasize the scanning rule for translation initiation and stress the importance of cloning genes of interest into or near the native NcoI start site of MFG-based retroviral vectors.

A high molecular weight melanoma-associated antigen-specific chimeric antigen receptor redirects lymphocytes to target human melanomas

Immunotherapy, particularly the adoptive cell transfer (ACT) of tumor-infiltrating lymphocytes (TIL), is a very promising therapy for metastatic melanoma. Some patients unable to receive TIL have been successfully treated with autologous peripheral blood lymphocytes (PBL), genetically modified to express human leukocyte antigen (HLA) class I antigen-restricted, melanoma antigen-reactive T-cell receptors; however, substantial numbers of patients remain ineligible due to the lack of expression of the restricting HLA class I allele. We sought to overcome this limitation by designing a non-MHC-restricted, chimeric antigen receptor (CAR) targeting the high molecular weight melanoma-associated antigen (HMW-MAA), which is highly expressed on more than 90% of human melanomas but has a restricted distribution in normal tissues. HMW-MAA-specific CARs containing an antigen recognition domain based on variations of the HMW-MAA-specific monoclonal antibody 225.28S and a T-cell activation domain based on combinations of CD28, 4-1BB, and CD3zeta activation motifs were constructed within a retroviral vector to allow stable gene transfer into cells and their progeny. Following optimization of the HMW-MAA-specific CAR for expression and function in human PBL, these gene-modified T cells secreted cytokines, were cytolytic, and proliferated in response to HMW-MAA-expressing cell lines. Furthermore, the receptor functioned in both CD4(+) and CD8(+) cells, was non-MHC restricted, and reacted against explanted human melanomas. To evaluate this HMW-MAA-specific CAR in patients with metastatic melanoma, we developed a clinical-grade retroviral packaging line. This may represent a novel means to treat the majority of patients with advanced melanoma, most notably those unable to receive current ACT therapies.

Both CD4 and CD8 T cells mediate equally effective in vivo tumor treatment when engineered with a highly avid TCR targeting tyrosinase

Tyrosinase, an enzyme involved in melanin synthesis, is expressed in nearly all primary and metastatic melanoma lesions and thus is an attractive target for TCR-based gene therapy using adoptive cell transfer. The TCR alpha- and beta-chain genes from a tumor-infiltrating lymphocyte, which recognized the tyrosinase 368-376 peptide in the context of HLA-A2, were cloned into a gamma-retroviral vector. Following transduction of PBL, specific reactivity was confirmed by cytokine production following coculture with tumor targets. Experiments using Ab blockade and CD4/CD8 sorting of the transduced PBLs demonstrated that this antityrosinase TCR was CD4/CD8 independent. The introduction of a second disulfide bond between the TCR constant regions and/or creation of a chimeric protein in which the human constant regions were replaced by murine homologs resulted in enhanced TCR expression as demonstrated by tetramer staining and improved tumor reactivity that was comparable to PBL transduced with either anti-melanoma Ag recognized by T cells-1 or anti-gp100 TCR vectors currently used in clinical trials. The chimeric TCR also allowed us to test antitumor function of in HLA-A2/K(b)-transgenic mice. Transfer of the antityrosinase TCR into mouse splenocytes conferred CD4/CD8-independent, HLA-A2-restricted Ag reactivity against B16/A2K(b) murine melanoma in vitro. Furthermore, adoptive transfer of transduced splenocytes mediated B16/A2K(b) melanoma tumor regression in lymphodepleted mice, and, surprisingly, both CD8 and CD4 T cells were equally effective in mediating tumor regression. These results suggest that this highly active tyrosinase-specific TCR could be of value in adoptive cell transfer for melanoma.

East meets West: how China almost cured malaria

With the isolation of quinine from Cinchona in 1820, an ancient herbal cure was transformed into a chemical drug. This was the inspiration for a new scientific discipline - ethnopharmacology - as Western scientists began to reinvent traditional herbal cures by extracting their active principles to make new and profitable drugs. The Chinese government may claim many such success stories as their own, but such triumphant narratives only reveal part of the story. The drawn-out hunt for the active principle of another anti-malarial herb, changshan, or Dichroa febrifuga, offers a more nuanced narrative that captures the complex interplay between traditional Chinese and Western medicine.