Feasibility and Clinical Utility of Reporting Hereditary Cancer Predisposition Pathogenic Variants Identified in Research Germline Sequencing: A Prospective Interventional Study.

PURPOSE: Patients with cancer frequently undergo research-grade germline sequencing but clinically actionable results are not routinely disclosed. The objective of this study is to evaluate the feasibility of reporting clinically relevant secondary findings (SF) identified in germline research sequencing using the institutional molecular tumor board (MTB) and the treating oncology physician. METHODS: This prospective, interventional cohort study enrolled Total Cancer Care participants with any cancer diagnosis at a single institution. Patients underwent research-grade germline whole-exome sequencing, with bioinformatic analysis in a Clinical Laboratory Improvement Amendments-certified laboratory to verify pathogenic/likely pathogenic germline variants (PGVs) in any American College of Medical Genomics and Genetics SF v2.0 genes. After a protocol modification in consenting patients, the MTB reported PGVs to treating oncology physicians with recommendations for referral to a licensed genetic counselor and clinical confirmatory testing. RESULTS: Of the 781 enrolled participants, 32 (4.1%) harbored cancer predisposition PGVs, 24 (3.1%) were heterozygous carriers of an autosomal recessive cancer predisposition syndrome, and 14 (1.8%) had other hereditary disease PGVs. Guideline-directed testing would have missed 37.5% (12/32) of the inherited cancer predisposition PGVs, which included BRCA1, BRCA2, MSH6, SDHAF2, SDHB, and TP53 variants. Three hundred fifteen participants consented to reporting results; results for all living patients were reported to the clinical team with half referred to a licensed genetic counselor. There was concordance between all research variants identified in patients (n = 9) who underwent clinical confirmatory sequencing. CONCLUSION: MTB reporting of research-grade germline sequencing to the clinical oncology team is feasible. Over a third of PGVs identified using a universal testing strategy would have been missed by guideline-based approach, suggesting a role for expanding germline testing.

Phase I Safety and Feasibility Pilot of Hepatic Artery Infusion Chemotherapy in a Rural Catchment Area Using The Codman Vascular Catheter with The Medtronic SynchroMed II Pump for Intrahepatic Cancers.

BACKGROUND: Discontinuation of the Codman 3000 pump in 2018 left no Food and Drug Administration (FDA)-approved hepatic artery infusion (HAI) device for unresectable colorectal liver metastases (uCLM) and intrahepatic cholangiocarcinoma (uIHC). Historically, HAI has been performed at academic medical centers in large metropolitan areas, which are often inaccessible to rural patients. Consequently, feasibility of dissemination of HAI to rural populations is unknown. PATIENTS AND METHODS: Under an FDA investigational device exemption, we opened the only HAI program in Kentucky and enrolled patients with uCLM and uIHC in a phase I clinical trial. The trial examined the safety of the hybrid Codman catheter/Medtronic SynchroMed II pump (hCMP) combination, defined as successful completion of one cycle of HAI chemotherapy. Rural feasibility was assessed by number of missed pump fills appointments. RESULTS: A total of 21 patients (n = 17 uCLM, n = 4 uIHC) underwent hCMP implantation before accrual was stopped early owing to FDA approval of the Intera 3000 pump. 20/21 (95%) patients met the primary safety endpoint. Serious adverse events (AEs) included a grade 5 coronavirus disease 2019 (COVID-19) infection (n = 1) and a grade 3 catheter erosion into the bowel (n = 1). Biliary sclerosis developed in two patients (9.5%). Median distance to infusion center was 47.6 miles (2-138 miles), and 62% were from Appalachia, yet there were no missed pump fill appointments. The 2-year overall survival was 82.4% (uCLM) and 50% (uIHC). CONCLUSIONS: The hCMP device had an acceptable safety profile. Despite the complexity of starting a new HAI program, early results showed feasibility for HAI delivery in a rural catchment area and comparable outcomes to larger urban-based HAI centers.

Current Practices in Hepatic Artery Infusion (HAI) Chemotherapy: An International Survey of the HAI Consortium Research Network.

BACKGROUND: An increasing number of hepatic artery infusion (HAI) programs have been established worldwide. Practice patterns for this complex therapy across these programs have not been reported. This survey aimed to identify current practice patterns in HAI therapy with the long-term goal of defining best practices and performing prospective studies. METHODS: Using SurveyMonkeyTM, a 28-question survey assessing current practices in HAI was developed by 12 HAI Consortium Research Network (HCRN) surgical oncologists. Content analysis was used to code textual responses, and the frequency of categories was calculated. Scores for rank-order questions were generated by calculating average ranking for each answer choice. RESULTS: Thirty-six (72%) HCRN members responded to the survey. The most common intended initial indications for HAI at new programs were unresectable colorectal liver metastases (uCRLM; 100%) and unresectable intrahepatic cholangiocarcinoma (uIHC; 56%). Practice patterns evolved such that uCRLM (94%) and adjuvant therapy for CRLM (adjCRLM; 72%) have become the most common current indications for HAI at established centers. Referral patterns for pump placement differed between uCRLM and uIHC, with most patients referred while receiving second- and first-line therapy, respectively, with physicians preferring to evaluate patients for HAI while receiving first-line therapy for CRLM. Concern for extrahepatic disease was ranked as the most important factor when considering a patient for HAI. CONCLUSIONS: Indication and patient selection factors for HAI therapy are relatively uniform across most HCRN centers. The increasing use of adjuvant HAI therapy and overall consistency of practice patterns among HCRN centers provides a robust environment for prospective data collection and randomized clinical trials.

Creation of EGD-Derived Gastric Cancer Organoids to Predict Treatment Responses.

Gastric adenocarcinoma (GAd) is the third leading cause of cancer-related deaths worldwide. Most patients require perioperative chemotherapy, yet methods to accurately predict responses to therapy are lacking. Thus, patients may be unnecessarily exposed to considerable toxicities. Here, we present a novel methodology using patient-derived organoids (PDOs) that rapidly and accurately predicts the chemotherapy efficacy for GAd patients. Methods:Endoscopic GAd biopsies were obtained from 19 patients, shipped overnight, and PDOs were developed within 24 h. Drug sensitivity testing was performed on PDO single-cells with current standard-of-care systemic GAd regimens and cell viability was measured. Whole exome sequencing was used to confirm the consistency of tumor-related gene mutations and copy number alterations between primary tumors, PDOs, and PDO single-cells. Results:Overall, 15 of 19 biopsies (79%) were appropriate for PDO creation and single-cell expansion within 24 h of specimen collection and overnight shipment. With our PDO single-cell technique, PDOs (53%) were successfully developed. Subsequently, two PDO lines were subjected to drug sensitivity testing within 12 days from initial biopsy procurement. Drug sensitivity assays revealed unique treatment response profiles for combination drug regimens in both of the two unique PDOs, which corresponded with the clinical response. Conclusions:The successful creation of PDOs within 24 h of endoscopic biopsy and rapid drug testing within 2 weeks demonstrate the feasibility of our novel approach for future applications in clinical decision making. This proof of concept sets the foundation for future clinical trials using PDOs to predict clinical responses to GAd therapies.

Starting a successful hepatic artery infusion pump program: A practical guide.

Implementation of a successful hepatic artery infusion pump program requires numerous factors to be in place, and the lack of any of these may lead to program failure. First and foremost, hepatic artery infusion pump programs must have adequate surgical expertise in the complex technical aspects of hepatic artery infusion pump implantation and postoperative management. Most new hepatic artery infusion pump programs are initiated by a surgeon and led in conjunction with a medical oncologist. Medical oncology experience in floxuridine dosing is critical in maximizing the treatment doses and the number of cycles administered while avoiding biliary toxicity. This is facilitated by collaboration with an engaged pharmacy team. To have adequate patient volume for a successful program, internal and external stakeholders must have buy-in, including surgical and medical oncology colleagues unfamiliar with hepatic artery infusion pumps, colorectal surgery, and other referring providers. Programmatic support must be obtained from the hospital, cancer center, and department administration. Day-to-day pump access for chemotherapy and maintenance saline fills must be performed by appropriately trained infusion nurses to avoid complications. Nuclear and diagnostic radiology experience is key to identifying extrahepatic perfusion and hepatic artery infusion pump-specific complications. Additionally, skilled interventional radiologists and gastroenterologists are necessary to identify and treat rare complications rapidly. Finally, given the current rapid expansion of hepatic artery infusion pump programs, new programs must identify engaged mentors to help guide patient selection, navigate the nuanced issues that may arise, and provide advice in the case of complications. Although hepatic artery infusion pump dissemination outside of several major tertiary centers previously had stalled, establishing a successful and active hepatic artery infusion pump is feasible with appropriate training, mentorship, and thoughtful assembly of a dedicated multidisciplinary team.

The Development of Investigator-Initiated Clinical Trials in Surgical Oncology.

Investigator-initiated trials (IITs) are designed by principal investigators who identify important, unaddressed clinical gaps and opportunities to answer these questions through clinical trials. Surgical oncologists are poised to lead IITs due to their multidisciplinary clinical practice and substantial research background. The process of developing, organizing, and implementing IITs is multifaceted and involves important steps including (but not limited to) navigating regulatory requirements, obtaining funding, and meeting enrollment targets. Here, the authors explore the steps, methodology, and barriers of IIT development by surgical oncologists and highlight the importance of IITs in oncology.

Interaction of immune checkpoint PD-1 and chemokine receptor 4 (CXCR4) promotes a malignant phenotype in pancreatic cancer cells.

Despite recent therapeutic advances, pancreatic ductal adenocarcinoma (PDAC) remains a devastating disease with limited therapeutic options. Immune checkpoint inhibitors (ICIs) have demonstrated promising results in many cancers, but thus far have yielded little clinical benefit in PDAC. Based on recent combined targeting of programmed cell death protein-1 (PD-1) and C-X-C chemokine receptor 4 (CXCR4) in patient-derived xenografts (PDXs) and a pilot clinical trial, we sought to elucidate potential interactions between PD-1 and CXCR4. We observed concomitant expression and direct interaction of PD-1 and CXCR4 in PDAC cells. This interaction was disrupted upon CXCR4 antagonism with AMD3100 and led to increased cell surface expression of PD-1. Importantly, CXCR4-mediated PDAC cell migration was also blocked by PD-1 inhibition. Our work provides a possible mechanism by which prior studies have demonstrated that combined CXCR4 and PD-1 inhibition leads to decreased tumor growth. This is the first report investigating PD-1 and CXCR4 interactions in PDAC cells and our results can serve as the basis for further investigation of combined therapeutic targeting of CXCR4 and PD-1.

Endogenous Pancreatic Cancer Cell PD-1 Activates MET and Induces Epithelial-Mesenchymal Transition to Promote Cancer Progression.

We recently demonstrated that immune checkpoint PD-1 was endogenously expressed in pancreatic ductal adenocarcinoma (PDAC) cells. Our data indicated that PD-1 proteins are not exclusive to immune cells and have unrecognized signal transduction cascades intrinsic to cancer cells. Building on this paradigm shift, we sought to further characterize PD-1 expression in PDAC. We utilized a phospho-explorer array to identify pathways upregulated by PD-1 signaling. We discovered PD-1-mediated activation of the proto-oncogene MET in PDAC cells, which was dependent on hepatocyte growth factor (MET ligand) and not secondary to direct protein interaction. We then discovered that the PD-1/MET axis in PDAC cells regulated growth, migration, and invasion. Importantly, the PD-1/MET axis induced epithelial-to-mesenchymal transition (EMT), a well-established early oncogenic process in PDAC. We observed that combined targeting of PDAC cell PD-1 and MET resulted in substantial direct tumor cell cytotoxicity and growth inhibition in PDAC cell lines, patient-derived organoids, and patient-derived xenografts independent of cytotoxic immune responses. This is the first report of PDAC-endogenous PD-1 expression regulating MET signaling, which builds upon our growing body of work showing the oncogenic phenotype of PD-1 expression in PDAC cells is distinct from its immunogenic role. These results highlight a paradigm shift that the tumor-specific PD-1 axis is a novel target to effectively kill PDAC cells by antagonizing previously unrecognized PD-1-dependent oncogenic pathways.

Targetable IDH1 mutation identified in a rare case of pancreatic serous cystadenocarcinoma but not a series of serous cystadenomas.

Serous cystadenocarcinoma (SCAC) of the pancreas is rare, with only 35 cases reported in the literature. We present a case of SCAC, comparing the clinical presentation, management and molecular features of this case to a series of serous cystadenoma (SCA), which may be a precursor. Compared with SCAs (n = 5), SCAC was larger (11.5 vs median 3.6 cm). The case of SCAC invaded the spleen and exhibited distant metastasis, a requirement for diagnosis since pathologic features are otherwise indistinguishable from SCA. VHL mutations have been reported in about half of SCA in the literature. Accordingly, we identified either somatic or germline VHL mutations in 3 of 5 SCAs (60%), yet no pathogenic mutation was identified in the SCAC. A somatic mutation in IDH1 was found in SCAC only. This has been associated with multiple malignancies, is targetable with the drug ivosidenib and should be studied as a progression factor in SCAC.

Factors Predicting Participation in the Prospective Genomic Sequencing Study, Total Cancer Care (TCC), in Kentucky.

PURPOSE: Large-scale genomic sequencing studies are driving oncology drug development. However, rural populations, like those residing in Appalachian Kentucky, are underrepresented in these efforts. In this study, we determined the frequency of participation, reasons for nonparticipation, and factors predicting the decision to participate in the Total Cancer Care (TCC) prospective genomic cohort study. METHODS: A total of 1,188 patients were invited to enroll in the TCC prospective cohort from December 2018 to May 2019. Declining patients were queried for their rationale for nonparticipation and their patient data were obtained from the Kentucky Cancer Registry (KCR). Logistic regression was used to assess the association between characteristics and study participation. The association of study participation with survival was modeled with Cox proportional-hazards regression. RESULTS: 90.9% (1,081) patients consented to participate. In multivariate analysis, factors significantly associated with participation were age, gender, treatment status, and race. Though overall more women participated in the study, men were more likely to participate than women when invited (OR 1.57). Younger, Caucasian individuals who had received chemotherapy, but not surgery, were also more likely to participate. Patients in the Kentucky Appalachian cohort were primarily rural, had less educational attainment, and lower socioeconomic status. Kentucky Appalachian patients were no less likely to enroll in TCC than non-Appalachian patients. Consented individuals had higher overall survival compared to those who declined. CONCLUSION: Though minorities, those with low socioeconomic status, and rural populations are underrepresented in genomic studies, they were no less likely to participate when given the opportunity, and participation was associated with better clinical outcomes.

Real-World Evaluation of Universal Germline Screening for Cancer Treatment-Relevant Pharmacogenes.

The purpose of this study was to determine the frequency of clinically actionable treatment-relevant germline pharmacogenomic variants in patients with cancer and assess the real-world clinical utility of universal screening using whole-exome sequencing in this population. Cancer patients underwent research-grade germline whole-exome sequencing as a component of sequencing for somatic variants. Analysis in a clinical bioinformatics pipeline identified clinically actionable pharmacogenomic variants. Clinical Pharmacogenetics Implementation Consortium guidelines defined clinical actionability. We assessed clinical utility by reviewing electronic health records to determine the frequency of patients receiving pharmacogenomically actionable anti-cancer agents and associated outcomes. This observational study evaluated 291 patients with cancer. More than 90% carried any clinically relevant pharmacogenetic variant. At least one disease-relevant variant impacting anti-cancer agents was identified in 26.5% (77/291). Nine patients with toxicity-associated pharmacogenomic variants were treated with a relevant medication: seven UGT1A1 intermediate metabolizers were treated with irinotecan, one intermediate DPYD metabolizer was treated with 5-fluorouracil, and one TPMT poor metabolizer was treated with mercaptopurine. These individuals were more likely to experience treatment-associated toxicities than their wild-type counterparts (p = 0.0567). One UGT1A1 heterozygote died after a single dose of irinotecan due to irinotecan-related adverse effects. Identifying germline pharmacogenomic variants was feasible using whole-exome sequencing. Actionable pharmacogenetic variants are common and relevant to patients undergoing cancer treatment. Universal pharmacogenomic screening can be performed using whole-exome sequencing data originally obtained for quality control purposes and could be considered for patients who are candidates for irinotecan, 5-fluorouracil, capecitabine, and mercaptopurine.

Locoregional Therapies for Colorectal Cancer Liver Metastases: Options Beyond Resection.

Colorectal cancer was the third most common malignancy worldwide in 2018, and most patients present with or develop distant metastases. Colorectal liver metastases are most commonly observed because of the vascular drainage of the colon and superior rectum. Current guidelines recommend surgical resection as first-line treatment; however, 80% to 90% of patients with colorectal liver metastases are ineligible for primary resection. For patients with unresectable disease, a multidisciplinary treatment approach is favored, incorporating systemic therapy and a toolbox of local ablative therapies. These treatments either aim at cytoreduction to enable a conversion to surgical resectability or control of disease progression and spread. Each of these treatments carries unique outcomes and risk profiles, thereby contributing to an individualized treatment strategy for patients with colorectal liver metastases. This review summarizes evidence on hepatic artery infusion, stereotactic body radiation therapy, thermal ablation, transarterial chemoembolization with drug-eluding beads, and transarterial radioembolization for treatment of colorectal liver metastases. Results of large-scale prospective and retrospective studies and international guidelines are discussed to provide detailed background on the current and prospective use of local ablative techniques in management of colorectal liver metastases.

Surgical Management of Sarcoma Metastatic to Liver.

Sarcomas are rare mesenchymal tumors with a propensity for hematogenous metastasis. Gastrointestinal stromal tumor (GIST) is the most common histologic subtype and the most common source of hepatic metastases. In the case of metastatic GIST, neoadjuvant imatinib can be used as a selection tool for the judicious application of surgery, where treatment-responsive patients who undergo resection to prevent the development of treatment-resistant clones have associated 10-year actuarial survival of 40%. Further advances for many of the non-GIST sarcoma subtypes will depend on the development of improved systemic therapies and evaluation of their activity in subtype or molecularly defined trials.

Prognostic Factors After Neoadjuvant Imatinib for Newly Diagnosed Primary Gastrointestinal Stromal Tumor.

INTRODUCTION: Neoadjuvant imatinib (Neo-IM) therapy may facilitate R0 resection in primary gastrointestinal stromal tumors (GISTs) that are large or in difficult anatomic locations. While response to preoperative tyrosine kinase inhibitors is associated with better outcome in metastatic GIST, little is known about prognostic factors after Neo-IM in primary GIST. STUDY DESIGN: Patients with primary GIST with or without synchronous metastases who underwent Neo-IM were retrospectively analyzed from a prospective maintained institutional database for Response Evaluation Criteria in Solid Tumors (RECIST), tumor viability, and mitotic rate. Overall survival (OS) was estimated by Kaplan-Meier and compared by log-rank test. Cox proportionate hazard models were used for univariate and multivariate analysis. RESULTS: One hundred and fifty patients were treated for a median of 7.1 months (range 0.2-160). By RECIST, partial response, stable disease, and progressive disease were seen in 40%, 51%, and 9%, respectively. By pathologic analysis, ≤ 50% of the tumor was viable in 72%, and the mitotic rate was ≤ 5/50HPF in 74%. On multivariate analysis, RECIST response and tumor viability were not associated with OS, while post-treatment high mitotic rate (hazard ratio (HR) for death 5.3, CI 2.3-12.4), R2 margins (HR 6.0, CI 2.3-15.5), and adjuvant imatinib (HR 0.4, CI 0.2-0.9) were (p < 0.05). Five-year OS was 81 vs. 38% for low vs. high mitotic rate; 81, 59, and 39% for R0, R1, and R2 margins; and 75 vs 61% for adjuvant vs. no adjuvant imatinib therapy (p < 0.05). CONCLUSIONS: In primary GIST undergoing Neo-IM therapy, progression was uncommon, but substantial down-sizing occurred in the minority. High tumor mitotic rate and incomplete resection following Neo-IM were associated with poor outcome, while adjuvant imatinib was associated with prolonged survival.

Outcome of 1000 Patients With Gastrointestinal Stromal Tumor (GIST) Treated by Surgery in the Pre- and Post-imatinib Eras.

OBJECTIVE: To characterize the results of surgery for gastrointestinal stromal tumor (GIST) in the pre and post-imatinib eras at a single institution and to identify current prognostic clinicopathologic factors. BACKGROUND: Imatinib has radically changed the management of GIST, yet the magnitude of impact on outcome across the spectrum of GIST presentation and relevance of historical prognostic factors are not well defined. METHODS: We retrospectively analyzed 1000 patients who underwent surgery for GIST at our institution from 1982 to 2016. Patients were stratified by presentation status as primary tumor only (PRIM), primary with synchronous metastasis (PRIM + MET), or metachronous recurrence/metastases (MET), and also imatinib era (before and after it became available). Cox proportional-hazard models and Kaplan-Meier methods were used to model and estimate overall survival (OS) and recurrence-free survival (RFS). RESULTS: OS was longer in the imatinib era compared with the pre-imatinib era in each presentation group, including in Miettinen high-risk primary tumors. Among PRIM patients from the pre-imatinib era, tumor site, size, and mitotic rate were independently associated with OS and RFS on multivariate analysis. PRIM patients in the imatinib era who received imatinib (neoadjuvant and/or adjuvant) had higher risk tumors, but after adjusting for treatment, only size >10 cm remained independently prognostic of RFS [hazard ratio (HR) 3.85, 95% confidence interval (CI) 2.00-7.40, P < 0.0001) and OS (HR 3.37, 95% CI 1.60-7.13, P = 0.001)]. CONCLUSIONS: Patients treated in the imatinib era had prolonged OS across all presentations. In the imatinib era, among site, size, and mitotic rate, high-risk features were associated with treatment with the drug, but only size >10 cm correlated with outcome. Imatinib should still be prescribed for patients with high-risk features.

Development of a Single-Cell Technique to Increase Yield and Use of Gastrointestinal Cancer Organoids for Personalized Medicine Application.

BACKGROUND: Organoids are excellent 3-dimensional in vitro models of gastrointestinal cancers. However, patient-derived organoids (PDOs) remain inconsistent and unreliable for rapid actionable drug sensitivity testing due to size variation and limited material. STUDY DESIGN: On day10/passage 2 after standard creation of organoids, half of PDOs were dissociated into single-cells with TrypLE Express Enzyme/DNase I and mechanical dissociation; and half of PDOs were expanded by the standard technique. Hematoxylin and eosin and immunohistochemistry with CK7 and CK20 were performed for characterization. Drug sensitivity testing was completed for single-cells and paired standard PDOs to assess reproducibility. RESULTS: After 2 to 3 days, >50% of single-cells reformed uniform miniature PDOs (∼50 µm). We developed 10 PDO single-cell lines (n = 4, gastric cancer, [GC]; and n = 6, pancreatic ductal adenocarcinoma, [PDAC]), which formed epithelialized cystic structures and by IHC, exhibited CK7(high)/CK20(low) expression patterns mirroring parent tissues. Compared with paired standard PDOs, single-cells (n = 2, PDAC; = 2, GC) showed similar architecture, albeit smaller and more uniform. Importantly, single cells demonstrated similar sensitivity to cytotoxic drugs to matched PDOs. CONCLUSIONS: PDO single-cells are accurate for rapid clinical drug testing in gastrointestinal cancers. Using early passage PDO single-cells facilitates high-volume drug testing, decreasing time from tumor sampling to actionable clinical decisions, and provides a personalized medicine platform to optimally select drugs for gastrointestinal cancer patients.

An Organotypic Microcosm for the Pancreatic Tumor Microenvironment.

Pancreatic duct adenocarcinoma (PDAC) is projected to become the second leading cause of cancer-related deaths in the next few years. Unfortunately, the development of novel therapies for PDAC has been challenged by a uniquely complex tumor microenvironment. The development of in vitro cancer organoids in recent years has demonstrated potential to increase therapies for patients with PDAC. Organoids have been established from PDAC murine and human tissues and they are representative of the primary tumor. Further, organoids have been shown beneficial in studies of molecular mechanisms and drug sensitivity testing. This review will cover the use of organoids to study PDAC development, invasiveness, and therapeutic resistance in the context of the tumor microenvironment, which is characterized by a dense desmoplastic reaction, hindered immune activity, and pro-tumor metabolic signaling. We describe investigations utilizing organoids to characterize the tumor microenvironment and also describe their limitations. Overall, organoids have great potential to serve as a versatile model of drug response and may be used to increase available therapies and improve survival for patients with PDAC.