Randomized, Multicenter, Phase II Trial of Gemcitabine and Cisplatin With or Without Veliparib in Patients With Pancreas Adenocarcinoma and a Germline BRCA/PALB2 Mutation

The Landscape and Therapeutic Targeting of BRCA1, BRCA2 and Other DNA Damage Response Genes in Pancreatic Cancer

Genes participating in the cellular response to damaged DNA have an important function to protect genetic information from alterations due to extrinsic and intrinsic cellular insults. In cancer cells, alterations in these genes are a source of genetic instability, which is advantageous for cancer progression by providing background for adaptation to adverse environments and attack by the immune system. Mutations in BRCA1 and BRCA2 genes have been known for decades to predispose to familial breast and ovarian cancers, and, more recently, prostate and pancreatic cancers have been added to the constellation of cancers that show increased prevalence in these families. Cancers associated with these genetic syndromes are currently treated with PARP inhibitors based on the exquisite sensitivity of cells lacking BRCA1 or BRCA2 function to inhibition of the PARP enzyme. In contrast, the sensitivity of pancreatic cancers with somatic BRCA1 and BRCA2 mutations and with mutations in other homologous recombination (HR) repair genes to PARP inhibitors is less established and the subject of ongoing investigations. This paper reviews the prevalence of pancreatic cancers with HR gene defects and treatment of pancreatic cancer patients with defects in HR with PARP inhibitors and other drugs in development that target these molecular defects.

Prognostic and predictive value of tumoral DNA damage repair protein expression in patients with resected pancreatic cancer

OBJECTIVE

DNA damage repair (DDR) gene mutations gained interest in the treatment of metastatic pancreatic cancer (PC) patients, but their relevance in adjuvant setting is not well characterized. We assessed the prognostic and predictive potential of tumoral expression of DDR proteins along with clinical and tumor characteristics in patients with resected PC.

PATIENTS AND METHODS

Patients with PC who underwent pancreatic resection in our institution between 2005 and 2017 were retrospectively retrieved. Tumoral expression of a panel of DDR proteins including BRCA1, BRCA2, ATM, and p53 with immunohistochemistry was evaluated and association with patient and tumor features as well as prognosis was assessed.

RESULTS

130 patients were included in the study. The median age was 61 and 66% were males, 57% had lymph node involvement and 17% had a vascular invasion. 25 patients (19%) had thrombosis at the time of diagnosis. Median overall survival (OS) and disease-free survival (DFS) were 21.6 and 11.8 months, respectively. More advanced disease stage (HR: 3.67 95% CI 1.48-9.12, p = 0.005), presence of thrombosis (HR: 2.01 95% CI 1.04-3.89, p = 0.039), high BRCA1 expression (HR: 2.25, 95% CI 1.13-5.48, p = 0.023) and high post-operative CA 19-9 level (>100 IU/ml) (HR:2.61 95% CI 1.40-4.89, p = 0.003) were associated with shorter DFS. BRCA2, ATM, and p53 expression were not associated with DFS or OS. Adjuvant gemcitabine-cisplatin regimen was not associated with increased DFS or OS in the whole group, neither in low or high expressors of BRCA1, BRCA2, ATM or p53.

CONCLUSION

Contrary to BRCA2, ATM, and P53, BRCA1 expression may be beneficial for prognosis in resected pancreatic cancer, while no predictive role was observed in terms of adjuvant platinum efficacy.

Incidence and Prevalence of Intraductal Papillary Mucinous Neoplasms in Individuals With BRCA1 and BRCA2 Pathogenic Variant

BACKGROUND

The natural history of branch-duct intraductal papillary neoplasm (BD-IPMN) in BRCA1/2 patients is unknown. Our goal was to estimate the incidence and prevalence of BD-IPMN and other pancreatic lesions in BRCA1/2 patients and compare it to that for average-risk individuals.

METHODS

We identified a cohort of BRCA1/2 patients followed at our institution between 1995 and 2020. Medical records and imaging results were reviewed to determine prevalence of pancreatic lesions. We then identified those who had undergone follow-up imaging and determined the incidence of new pancreatic lesions. We categorized pancreatic lesions as low, intermediate, or high-risk based on their malignant potential.

RESULTS

During the study period, 359 eligible BRCA1/2 patients were identified. Average patient age was 56.8 years, 88.3% were women, and 51.5% had BRCA1 . The prevalence of low-risk pancreatic lesions was 14.4%, intermediate-risk 13.9%, and high-risk 3.3%. The prevalence of BD-IPMN was 13.6% with mean cyst size 7.7 mm (range: 2 to 34 mm). The prevalence of pancreatic cancer was 3.1%. Subsequent imaging was performed in 169 patents with mean follow-up interval of 5.3 years (range: 0 to 19.7 y). The incidence of BD-IPMN was 20.1%, with median cyst size 5.5 mm (range: 2 to 30 mm). The incidence of pancreatic cancer was 2.9%. BRCA2 patients were almost 4-times more likely to develop pancreatic cancer than BRCA1 patients, however, there was no difference in incidence or prevalence of BD-IPMN.

CONCLUSIONS

Incidence and prevalence of BD-IPMNs in BRCA1/2 patients was similar to that reported for average-risk individuals. BRCA2 patients were more likely than BRCA1 patients to develop pancreatic cancer but had similar rates of BD-IPMN.

Systemic Therapy for Patients With Pancreatic Cancer: Current Approaches and Opportunities for Novel Avenues Toward Precision Medicine

Pancreatic ductal adenocarcinoma (PDAC) has a dismal prognosis with a 5-year overall survival of 11%. The disease is usually diagnosed at advanced stages, and systemic chemotherapy is the standard-of-care treatment for the majority of patients with PDAC. Although novel treatment options, such as targeted therapy and immunotherapy, have achieved substantial progress leading to practice-changing results, with FDA approvals for several solid tumors so far, the progress achieved for PDAC is relatively limited. Recent studies uncovered potential therapeutic targets for patients with PDAC, and potential therapeutic opportunities are currently being further examined. Herein, we review recent advances in systemic therapy regimens, including cytotoxic agents, targeted therapies, immunotherapy, and novel therapeutic options for managing patients with PDAC. We also elaborate on molecular profiling to guide treatment and existing therapeutic opportunities that may further advance the clinical care of patients with this devastating disease.

Targeted therapy for pancreatic ductal adenocarcinoma: Mechanisms and clinical study

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

A case of unresectable intrahepatic cholangiocarcinoma with a germline BRCA1 mutation

Intrahepatic cholangiocarcinoma (ICC) is a malignant liver tumor with poor prognosis. Various mutations in cancer-predisposing genes have been reported in ICC, and germline BRCA1/2 mutations, which are the causative genes for hereditary breast and ovarian cancer syndrome (HBOC), have been reported in many patients with ICC. Here, we report a case of unresectable ICC with a germline BRCA1 mutation. A 73-year-old man was found to have a mass in the left lobe of the liver on abdominal ultrasonography during a medical check-up and was referred to our institution. Contrast-enhanced computed tomography revealed a 30-mm mass with a delayed enhancement pattern, tumor invasion into the major blood vessels, and enlarged regional lymph nodes. Ultrasound-guided percutaneous tumor biopsy revealed a well-differentiated adenocarcinoma, and the patient was diagnosed with clinical Stage IIIB ICC. Systemic chemotherapy with gemcitabine and cisplatin was initiated because of the unresectable nature of the disease. Regarding family history, his eldest daughter was diagnosed with HBOC with a germline BRCA1 mutation at the time of breast cancer surgery, and she developed pancreatic cancer seven years later. The patient underwent BRCA1 single-site analysis and was diagnosed with HBOC with a germline BRCA1 mutation.

Incidence and risk of hypertension associated with PARP inhibitors in cancer patients: a systematic review and meta-analysis

OBJECTIVE

To analyze the incidence and risk of hypertension associated with poly(adenosine diphosphate-ribose) polymerase (PARP) inhibitors in cancer patients and provide reference for clinicians.

METHODS

We used R software to conduct a meta-analysis of phase II/III randomized controlled trials (RCT) on PARP inhibitors for cancer treatment published in PubMed, Embase, Clinical Trials, Cochrane Library and Web of Science from inception to July 29th, 2022.

RESULTS

We included 32 RCTs with 10,654 participants for this meta-analysis. For total PARP inhibitors, the incidence and risk ratio of all-grade hypertension were 12% and 1.22 (95% CI: 0.91-1.65, P = 0.19, I² = 81%), and the incidence and risk ratio of grade 3-4 hypertension were 4% and 1.24 (95% CI: 0.74-2.08, P = 0.42, I² = 68%). Compared with the control group, the niraparib group, olaparib 800 mg/day group, and olaparib plus cediranib group increased the risk of any grade and grade 3-4 hypertension, while the veliparib group and rucaparib group did not increase the risk of any grade and grade 3-4 hypertension, and olaparib 200 mg-600 mg/day group (exclude olaparib plus cediranib regime) reduced the risk of any grade and grade 3-4 hypertension.

CONCLUSION

Olaparib 200-600 mg/day (excluding olaparib plus cediranib regimen) may be the most suitable PARP inhibitor for cancer patients with high risk of hypertension, followed by veliparib and rucaparib. Niraparib, olaparib 800 mg/day and olaparib combined with cediranib may increase the risk of developing hypertension in cancer patients, clinicians should strengthen the monitoring of blood pressure in cancer patients and give medication in severe cases.

Genetics, Genomics and Emerging Molecular Therapies of Pancreatic Cancer

The number of cases of pancreatic cancers in 2019 in Poland was 3852 (approx. 2% of all cancers). The course of the disease is very fast, and the average survival time from the diagnosis is 6 months. Only <2% of patients live for 5 years from the diagnosis, 8% live for 2 years, and almost half live for only about 3 months. A family predisposition to pancreatic cancer occurs in about 10% of cases. Several oncogenes in which somatic changes lead to the development of tumours, including genes BRCA1/2 and PALB2, TP53, CDKN2A, SMAD4, MLL3, TGFBR2, ARID1A and SF3B1, are involved in pancreatic cancer. Between 4% and 10% of individuals with pancreatic cancer will have a mutation in one of these genes. Six percent of patients with pancreatic cancer have NTRK pathogenic fusion. The pathogenesis of pancreatic cancer can in many cases be characterised by homologous recombination deficiency (HRD)-cell inability to effectively repair DNA. It is estimated that from 24% to as many as 44% of pancreatic cancers show HRD. The most common cause of HRD are inactivating mutations in the genes regulating this DNA repair system, mainly BRCA1 and BRCA2, but also PALB2, RAD51C and several dozen others.

Identification and Validation of Potentially Clinically Relevant CpG Regions within the Class 2 Tumor Suppressor Gene SFRP1 in Pancreatic Cancer

In pancreatic cancer treatment, tumor stage-dependent chemotherapies are used to prolong overall survival. By measuring DNA promoter hypermethylation in the plasma of patients with stage IV pancreatic cancer, it was recently shown that promoter DNA methylation of the tumor suppressor gene SFRP1 has a high value for predicting failure of drug treatment with gemcitabine. In this study, we therefore aimed to identify as precisely as possible the region in the SFRP1 promoter that is frequently hypermethylated in pancreatic cancer tissue. First, we used the TCGA data set to define CpG-rich regions flanking the SFRP1 transcription start site that were significantly more methylated in pancreatic cancer compared to normal pancreatic acinar tissue. A core CpG island was identified that exhibited abundant tumor DNA methylation and anti-correlation of SFRP1 mRNA expression. To validate our in silico results, we performed bisulfide conversion followed by DNA pyrosequencing of 28 matched formalin-fixed, paraffin-embedded (FFPE) pancreatic cancer cases and six pancreatic cancer cell lines. A defined block of seven CpG sites within the core CpG island was identified, which confirmed our in silico results by showing significantly higher SFRP1 methylation in pancreatic cancer specimens than in normal pancreatic tissue. By selecting this core CpG island, we were able to determine a median overall survival benefit for the low SFRP1 methylation group compared to the high SFRP1 methylation group (702 versus 517 days, p = 0.01) in the TCGA pancreatic cancer cohort. We propose a compact pyrosequencing assay that can be used in the future to further investigate the prognostic value of SFRP1 promoter hypermethylation in predicting pancreatic cancer chemoresistance. Therefore, instead of DNA analysis from blood (liquid biopsy), DNA easily extractable from cancer tissue blocks (FFPE material) could be used.

Efficacy of chemotherapy according to BRCA status in patients with high-grade serous ovarian carcinoma at first platinum-sensitive relapse

OBJECTIVE

Chemotherapy for high-grade serous ovarian cancers in platinum-sensitive relapse includes carboplatin/paclitaxel, carboplatin/gemcitabine, and carboplatin/pegylated liposomal doxorubicin. According to in vitro data, BRCA mutated patients are sensitive to replicative stress agents but BRCA status is not yet used for the choice of chemotherapy at relapse. Our aim was to assess these doublets according to BRCA status in first platinum-sensitive relapse.

METHODS

The ESME ovarian cancer database comprises a multicenter retrospective cohort of patients with ovarian cancer treated in French cancer centers between January 2011 and December 2017. Patients with high-grade serous ovarian cancers at first platinum-sensitive relapse who received one of these doublets were included. The objective was to compare progression-free survival of each chemotherapy doublet according to BRCA status.

RESULTS

Among the 10 263 patients in the database, 1539 patients had a first platinum-sensitive relapse: 825 BRCA wild type patients (53.6%) and 304 BRCA mutated patients (19.8%) (7 patients had a homologous recombination mutation and BRCA status was unkown for 403 patients). Median progression-free survival was longer in BRCA mutated patients than in BRCA wild type patients when receiving carboplatin/pegylated liposomal doxorubicin without maintenance treatment (15.8 vs 11.8 months; p<0.001). In contrast, we observed no difference in patients treated with carboplatin/paclitaxel (14.6 vs 14.3 months, respectively; p=0.70) or in those treated with carboplatin/gemcitabine (12.0 vs 9.8 months, respectively; p=0.18). In BRCA wild type patients without maintenance, better progression-free survival occurred with carboplatin/paclitaxel (median progression-free survival 14.3 months) than with carboplatin/gemcitabine and carboplatin/pegylated liposomal doxorubicin (9.8 and 11.8 months, respectively; p=0.017). In BRCA mutated patients without maintenance, there was no difference between the three doublets (median progression-free survival of 14.6, 12.0, and 15.8 months with carboplatin/paclitaxel, carboplatin/gemcitabine, and carboplatin/pegylated liposomal doxorubicin, respectively; p=0.40).

CONCLUSION

While treatment with carboplatin/paclitaxel, carboplatin/gemcitabine, and carboplatin/pegylated liposomal doxorubicin shows comparable efficacy in BRCA mutated patients, treatment with carboplatin/paclitaxel appears to be more effective than carboplatin/gemcitabine and carboplatin/pegylated liposomal doxorubicin in BRCA wild type patients with high-grade serous ovarian cancers at first platinum-sensitive relapse.

Strategies for the Management of Patients with Pancreatic Cancer with PARP Inhibitors

A subset of patients with pancreatic adenocarcinomas (PDAC) harbor mutations that are exploitable in the context of DNA-damage response and repair (DDR) inhibitory strategies. Between 8-18% of PDACs harbor specific mutations in the DDR pathway such as BRCA1/2 mutations, and a higher prevalence exists in high-risk populations (e.g., Ashkenazi Jews). Herein, we will review the current trials and data on the treatment of PDAC patients who harbor such mutations and who appear sensitive to platinum and/or poly ADP ribose polymerase inhibitor (PARPi) based therapies due to a concept known as synthetic lethality. Although this current best-in-class precision treatment shows clinical promise, the specter of resistance limits the extent of therapeutic responses. We therefore also evaluate promising pre-clinical and clinical approaches in the pipeline that may either work with existing therapies to break resistance or work separately with combination therapies against this subset of PDACs.

Current Treatment of Potentially Resectable Pancreatic Ductal Adenocarcinoma: A Medical Oncologist's Perspective

Pancreatic cancer has traditionally been associated with a dismal prognosis, even in early stages of the disease. In recent years, the introduction of newer generation chemotherapy regimens in the adjuvant setting has improved the survival of patients treated with upfront resection. However, there are multiple theoretical advantages to deliver early systemic therapy in patients with localized pancreatic cancer. So far, the evidence supports the use of neoadjuvant therapy for patients with borderline resectable pancreatic cancer. The benefit of this treatment sequence for patients with resectable disease remains elusive. In this review, we summarize the data on adjuvant therapy for pancreatic cancer and describe which evidence backs the use of neoadjuvant therapy. Additionally, we address important issues faced in clinical practice when treating patients with localized pancreatic cancer.

Combining Poly (ADP-Ribose) Polymerase (PARP) Inhibitors with Chemotherapeutic Agents: Promise and Challenges

Better understanding of molecular drivers and dysregulated pathways has furthered the concept of precision oncology and rational drug development. The role of DNA damage response (DDR) pathways has been extensively studied in carcinogenesis and as potential therapeutic targets to improve response to chemotherapy or overcome resistance. Treatment with small molecule inhibitors of PARP has resulted in clinical response and conferred survival benefit to patients with ovarian cancer, BRCA-mutant breast cancer, HRD-deficient prostate cancer and BRCA-mutant pancreatic cancer, leading to US Food and Drug Administration (FDA) approvals. However, the observed clinical benefit with single agent PARP inhibitors is limited to few tumor types within the relevant genetic context. Since DDR pathways are essential for repair of damage caused by cytotoxic agents, PARP inhibitors have been evaluated in combination with various chemotherapeutic agents to broaden the therapeutic application of this class of drugs. In this chapter, we discuss the combination of PARP inhibitors with different chemotherapeutics agents, clinical experience to date, lessons learnt, and future directions for this approach.

Pancreatic Adenocarcinoma Management

The management of pancreatic ductal adenocarcinoma (PDAC) has evolved over the last two decades. Surgical resection remain the only potential cure for this cancer. Therefore, there is an emerging emphasis on neoadjuvant therapy to maximize the probability of resection, and identify failures early. The benefit of FOLFIRINOX in various clinical stages of PDAC have been practice changing. The addition of nab-paclitaxel to the traditional gemcitabine regimen added another option for treatment. In addition, immunotherapy and targeted therapies are applicable, based on molecular features and germline alterations; albeit, these are applicable to only a small minority of patients. In this review article, we discuss the key extant literature relevant to various stages of pancreatic cancer. We also summarize ongoing clinical trials which may guide future treatments.

Increasing Stress to Induce Apoptosis in Pancreatic Cancer via the Unfolded Protein Response (UPR)

High rates of cell proliferation and protein synthesis in pancreatic cancer are among many factors leading to endoplasmic reticulum (ER) stress. To restore cellular homeostasis, the unfolded protein response (UPR) activates as an adaptive mechanism through either the IRE1α, PERK, or ATF6 pathways to reduce the translational load and process unfolded proteins, thus enabling tumor cells to proliferate. Under severe and prolonged ER stress, however, the UPR may promote adaptation, senescence, or apoptosis under these same pathways if homeostasis is not restored. In this review, we present evidence that high levels of ER stress and UPR activation are present in pancreatic cancer. We detail the mechanisms by which compounds activate one or many of the three arms of the UPR and effectuate downstream apoptosis and examine available data on the pre-clinical and clinical-phase ER stress inducers with the potential for anti-tumor efficacy in pancreatic cancer. Finally, we hypothesize a potential new approach to targeting pancreatic cancer by increasing levels of ER stress and UPR activation to incite apoptotic cell death.

Emerging Role of Targeted Therapy in Metastatic Pancreatic Adenocarcinoma

The aggressive biology of pancreatic ductal adenocarcinoma (PDAC), along with its limited sensitivity to many systemic therapies, presents a major challenge in the management of patients with metastatic PDAC. Over the past decade, the incorporation of combinatorial cytotoxic chemotherapy regimens has improved patient outcomes. Despite these advances, resistance to cytotoxic chemotherapy inevitably occurs, and there is a great need for effective therapies. A major focus of research has been to identify molecularly defined subpopulations of patients with PDAC who may benefit from targeted therapies that are matched to their molecular profile. Recent successes include the demonstration of the efficacy of maintenance PARP inhibition in PDAC tumors harboring deleterious BRCA1, BRCA2, and PALB2 alterations. In addition, while therapeutic targeting of KRAS was long thought to be infeasible, emerging data on the efficacy of KRAS G12C inhibitors have increased optimism about next-generation KRAS-directed therapies in PDAC. Meanwhile, KRAS wild-type PDAC encompasses a unique molecular subpopulation of PDAC that is enriched for targetable genetic alterations, such as oncogenic BRAF alterations, mismatch repair deficiency, and FGFR2, ALK, NTRK, ROS1, NRG1, and RET rearrangements. As more molecularly targeted therapies are developed, precision medicine has the potential to revolutionize the treatment of patients with metastatic PDAC.

Pancreatic Cancer: Beyond Brca Mutations

Pancreatic cancer is the fourth-leading cause of cancer-related deaths worldwide. The outcomes in patients with pancreatic cancer remain unsatisfactory. In the current review, we summarize the genetic and epigenetic architecture of metastatic pancreatic cancer beyond the BRCA mutations, focusing on the genetic alterations and the molecular pathology in pancreatic cancer. This review focuses on the molecular targets for the treatment of pancreatic cancer, with a correlation to future treatments. The potential approach addressed in this review may lead to the identification of a subset of patients with specific biological behaviors and treatment responses.

NGS-based targeted gene mutational profiles in Korean patients with pancreatic cancer

According to molecular profiling studies, a considerable number of patients with pancreatic cancer harbor potentially actionable mutations. However, there are limited relevant data from the Korean population. We assessed the molecular profiles of patients with pancreatic cancer in Korea. This study collected molecular profiling data from patients with pancreatic cancer who visited Seoul National University Bundang Hospital between March 2018 and August 2020. Formalin-fixed, paraffin-embedded tumor specimens were sequenced using a targeted next-generation sequencing (NGS) platform. Cancer-associated mutations were analyzed, and potentially actionable mutations were identified. Potentially actionable mutations were classified into "highly actionable" and "modifies options" based on the Know Your Tumor registry study. In total, 87 patients with NGS tumor panel data were identified. Sixty-one patients (70.1%) had metastatic disease at the time of tissue acquisition. Tissues were obtained from the primary tumors and metastatic sites in 41 (47.1%) and 46 (52.9%) patients, respectively. At least one pathogenic mutation was reported in 86 patients (98.9%). The frequencies of four common mutations in our cohort were similar to those in The Cancer Genome Atlas data. Potentially actionable mutations were identified in 27 patients (31.0%). Of these, mutations categorized as highly actionable and modifies options were identified in 12 (13.8%) and 18 patients (20.7%), respectively. The most frequent highly actionable mutations were located in DNA damage response genes, such as BRCA1, BRCA2, or ATM (n = 6, 6.9%). Two patients with germline BRCA1 mutations received maintenance poly(adenosine diphosphate-ribose) polymerase inhibitor therapy. One patient has been receiving maintenance treatment for 18 months while remaining in radiologically complete remission. Mutational profiles using targeted NGS in Korean patients with pancreatic cancer were similar to those in Western patients. The present study supports the clinical potential and possible expanded clinical use of genetic profiling.

Overall Survival Results From the POLO Trial: A Phase III Study of Active Maintenance Olaparib Versus Placebo for Germline BRCA-Mutated Metastatic Pancreatic Cancer

PURPOSE

The phase III POLO study demonstrated significant progression-free survival (PFS) benefit for active olaparib maintenance therapy versus placebo for patients with metastatic pancreatic adenocarcinoma and a germline BRCA mutation. Here, we report the final analysis of overall survival (OS) and other secondary end points.

PATIENTS AND METHODS

Patients with a deleterious or suspected deleterious germline BRCA mutation whose disease had not progressed after ≥ 16 weeks of first-line platinum-based chemotherapy were randomly assigned 3:2 to active maintenance olaparib (300 mg twice daily) or placebo. The primary end point was PFS; secondary end points included OS, time to second disease progression or death, time to first and second subsequent cancer therapies or death, time to discontinuation of study treatment or death, and safety and tolerability.

RESULTS

In total, 154 patients were randomly assigned (olaparib, n = 92; placebo, n = 62). No statistically significant OS benefit was observed (median 19.0 v 19.2 months; hazard ratio [HR], 0.83; 95% CI, 0.56 to 1.22; P = .3487). Kaplan-Meier OS curves separated at approximately 24 months, and the estimated 3-year survival after random assignment was 33.9% versus 17.8%, respectively. Median time to first subsequent cancer therapy or death (HR, 0.44; 95% CI, 0.30 to 0.66; P < .0001), time to second subsequent cancer therapy or death (HR, 0.61; 95% CI, 0.42 to 0.89; P = .0111), and time to discontinuation of study treatment or death (HR, 0.43; 95% CI, 0.29 to 0.63; P < .0001) significantly favored olaparib. The HR for second disease progression or death favored olaparib without reaching statistical significance (HR, 0.66; 95% CI, 0.43 to 1.02; P = .0613). Olaparib was well tolerated with no new safety signals.

CONCLUSION

Although no statistically significant OS benefit was observed, the HR numerically favored olaparib, which also conferred clinically meaningful benefits including increased time off chemotherapy and long-term survival in a subset of patients.

Genomic landscape of pancreatic cancer in the Japanese version of the Cancer Genome Atlas

Background

Pancreatic cancer (PC) is one of the most aggressive cancers worldwide. Although many studies have investigated genomic alterations, the genomic landscape of Japanese PC patients has not been fully elucidated.

Methods

We used whole-exome sequencing, cancer gene panel deep-sequencing, and microarray gene expression profiling data derived from the Japanese version of the Cancer Genome Atlas (JCGA) in 93 PC cases.

Results

Somatic driver mutations were identified in 65.6% of samples in 19 genes. The median tumor mutation burden (TMB) value was 0.24 Muts/Mb (interquartile range, 0.15-0.64 Muts/Mb). The commonly mutated genes were KRAS (58%), TP53 (40%), CDKN2A (10%), SMAD4 (10%), FGFR2 (9%), and PKHD1 (9%). Frequent germline variation genes were BRCA1 (8%), CDH1 (5%), MET (5%), MSH6 (5%), and TEK (5%). Frequent chromosomal arm alterations included copy number gains in 2q (42%), 7q (24%), and 3q (24%), and copy number losses in 19p (62%), 19q (47%), 12q (34%), and 7q (30%). A prognostic analysis according to the presence of driver mutations showed that overall survival (OS) in the driver mutation-positive group was significantly worse in comparison to that of the driver mutation-negative group (median, 23.1 vs 46.7 mo; P = .010). A Cox proportional hazards analysis for OS identified driver mutation (hazard ratio [HR], 1.89; P = .025) and lymph node metastasis (HR, 3.27; P = .002) as independent prognostic factors.

Conclusion

The present results from the JCGA dataset constitute a fundamental resource for genomic medicine for PC patients, especially in Japan.

Clinico-genomic Characterization of ATM and HRD in Pancreas Cancer: Application for Practice

PURPOSE

Characterizing germline and somatic ATM variants (gATMm, sATMm) zygosity and their contribution to homologous recombination deficiency (HRD) is important for therapeutic strategy in pancreatic ductal adenocarcinoma (PDAC).

EXPERIMENTAL DESIGN

Clinico-genomic data for patients with PDAC and other cancers with ATM variants were abstracted. Genomic instability scores (GIS) were derived from ATM-mutant cancers and overall survival (OS) was evaluated.

RESULTS

Forty-six patients had PDAC and pathogenic ATM variants including 24 (52%) stage III/IV: gATMm (N = 24), and sATMm (N = 22). Twenty-seven (59%) had biallelic, 15 (33%) monoallelic, and 4 indeterminate (8%) variants. Median OS for advanced-stage cohort at diagnosis (N = 24) was 19.7 months [95% confidence interval (CI): 12.3-not reached (NR)], 27.1 months (95% CI: 22.7-NR) for gATMm (n = 11), and 12.3 months for sATMm (n = 13; 95% CI: 11.9-NR; P = 0.025). GIS was computed for 33 patients with PDAC and compared with other ATM-mutant cancers enriched for HRD. The median was lower (median, 11; range, 2-29) relative to breast (18, 3-55) or ovarian (25, 3-56) ATM-mutant cancers (P < 0.001 and P = 0.003, respectively). Interestingly, biallelic pathogenic ATM variants were mutually exclusive with TP53. Other canonical driver gene (KRAS, CDKN2A, SMAD4) variants were less frequent in ATM-mutant PDAC.

CONCLUSIONS

ATM variants in PDAC represent a distinct biologic group and appear to have favorable OS. Nonetheless, pathogenic ATM variants do not confer an HRD signature in PDAC and ATM should be considered as a non-core HR gene in this disease.

The molecular landscape of pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is predicted to become the second leading cause of cancer-related mortality within the next decade, with limited effective treatment options and a dismal long-term prognosis for patients. Surgical resection of early, localised disease provides the only chance for potentially curative treatment; however, most patients with PDAC present with advanced disease and are not suitable for surgery. Genomic analyses of PDAC tumour lesions have identified a small number of recurrent alterations that are detected across most tumours, and beyond that a large number that either occur at a low (<5%) prevalence or are patient-specific in nature. This molecular heterogeneity has presented a significant challenge for the characterisation of tumour subtypes and effective molecular biomarkers, which have not yet manifested clinical benefits for diagnosis, treatment or prognosis in PDAC. These challenges are compounded by the overall lack of tumour biopsies for sequencing, the invasive nature of tissue sampling and the confounding effects of low tumour cellularity in many PDAC biopsy specimens, which have limited the applications of molecular profiling in unresectable patients and for longitudinal tumour monitoring. Further investigation into alternative sources of tumour analytes that can be sampled using minimally invasive methods and used to complement molecular analyses from tissue sequencing are required.

Endoscopic ultrasound-guided tissue acquisition for pancreatic ductal adenocarcinoma in the era of precision medicine

Endoscopic ultrasound-guided tissue acquisition (EUS-TA) currently plays a central role in the diagnosis of pancreatic ductal adenocarcinoma (PDAC). Although fine-needle aspiration has been the gold standard, novel biopsy needles for fine-needle biopsy (FNB) were developed to overcome its limitations, which include low tumor cellularity and the inability to retain cellular architecture. Following recent improvements in FNB needles, the pathological diagnosis has shifted from cytology to histology and now to genetic diagnosis. Genetic analysis using EUS-TA samples began with a search for the presence of K-ras mutations. However, the introduction of next-generation sequencers has dramatically changed genetic analysis and led to the gradual elucidation of the mechanism of PDAC, enabling personalized medicine by performing multiple gene analyses simultaneously. Comprehensive genomic profiling is currently applied in the clinical setting and there is an increasing need for gene analysis using EUS-TA samples. Although target genome sequencing is feasible even with cytological specimens, it can be difficult to proceed with full genetic analysis including whole-exome sequence or whole-genome sequence if the samples are too small. Genetic analysis will become highly important in determining indications for personalized medicine such as poly (ADP-ribose) polymerase inhibitors or immune checkpoint inhibitors. Therefore, the endosonographer must always take gene analysis into consideration when collecting samples for diagnosis and further improvement of the puncture technique and needle development are anticipated in the future.

Concurrent loss of MLH1, PMS2 and MSH6 immunoexpression in digestive system cancers indicating a widespread dysregulation in DNA repair processes

Immunohistochemical analysis of mismatch repair (MMR) protein expression is widely used to identify tumors with a deficient MMR (dMMR). MMR proteins (MLH1/PMS2 and MSH2/MSH6) work as functional heterodimers, which usually leads to the loss of expression in only one functional MMR heterodimer. Recently, there have been studies showing the simultaneous loss of immunoexpression in proteins of both heterodimers. Yet, this phenomenon has been rarely investigated. In this study, we retrospectively considered cases of different digestive system cancers (gastric cancer, ampullary cancer, small bowel cancer, colorectal cancer), which were immunohistochemically tested for dMMR within a 4-year period at our university hospital (n=352). Of the 103 cases showing dMMR, 5 cases (1.4% of all, 5.1% of dMMR cases) showed a concurrent loss of MLH1, PMS2 and MSH6 immunoexpression, whereas in the other 98 dMMR cases only one MMR heterodimer was affected. MLH1^-/PMS2^-/MSH6^- cancer cases almost arose throughout the entire digestive tract: from the gastric antrum to the left colic flexur. To provide a comprehensive molecular characterization of this MLH1^-/PMS2^-/MSH6^- immunophenotype, tumors were analyzed for microsatellite instability, MLH1 promotor hypermethylation and BRAF exon 15 status. Furthermore, we performed next-generation sequencing focusing on genes related to DNA repair. Here, we could detect pathogenic germline variants as well as multiple sporadic mutations in different genes involved in MMR and homologous recombination repair (HRR) respectively. The affected MMR/HRR-related genes were: ATM, BARD1, BRCA1, CDK12, CHEK1, CHEK2, FANCA, MLH1, MSH6, PALB2, TP53. Considering the biologic function of HRR/MMR proteins as potential drug targets and the low frequency of most of these mutations in digestive system cancers in general, their common occurrence in our MLH1^-/PMS2^-/MSH6^- cases seems to be even more noteworthy, highlighting the need for recognition, awareness and further investigation of this unusual IHC staining pattern.

Olaparib as a single agent treatment in pre-treated metastatic pancreatic cancer patient harboring BRCA2 mutation: What could we expect?

Background:

Despite ongoing developments, pancreatic cancer remains one of the most difficult tumors to treat. Even the most effective chemotherapy regimens, only marginally improve the outcome of Pancreatic cancer patients, which rarely exceeds one year. A small subset of Pancreatic cancer patients, carriers of germline variants of BRCA1/2, are clinically relevant as therapeutic targets in pancreatic cancer, both for the first-line and maintenance therapy, as they are more responsive to platinum-based chemotherapy agents and PARP inhibitors. Though, a little is known about the efficacy of olaparib monotherapy in later lines, or in poor responders to platinum-based regimens.

Methods:

We describe a case of a patient with pancreatic cancer harboring BRCA2 mutation, treated with radical surgery, adjuvant treatment and three different palliative chemotherapy regimens at disease recurrence (FOLFOX in first line with progression-free survival of five months, gemcitabine and nab-paclitaxel in the second line with progression-free survival of six months and FOLFIRI in the third line with progression-free survival of three months) before olaparib off-label treatment.

Results:

Interestingly, the patient remained 10 months on olaparib treatment, without disease progression, and without any side effects from the treatment.

Conclusion:

In conclusion, this case highlights the clinically relevant progression-free survival with olaparib treatment in later line and the potential of better health-related quality of life in this small subset of Pancreatic cancer patients.

Mitomycin C in Homologous Recombination Deficient Metastatic Pancreatic Cancer after Disease Progression on Platinum-Based Chemotherapy and Olaparib

Recent efforts to personalize treatment with platinum-based chemotherapy and PARP inhibitors have produced promising results in homologous recombinant deficient (HRD) metastatic pancreatic cancer (MPC). However, new strategies are necessary to overcome resistance. The below case series documents patients treated at the HonorHealth Research Institute with a diagnosis of HRD MPC who received Mitomycin C (MMC) treatment from January 2013 until July 2018. Five HRD MPC patients treated with MMC were evaluated. All patients received at least one course of treatment. Mean age at MMC treatment initiation was 58 years. There were 3 females and 2 males. All patients had tumors that progressed on platinum-based chemotherapy, four patients had previous exposure to Olaparib. The median PFS was 10.1 months, and the median OS was 12.3 months. Responses were observed only in patients harboring BRCA2 mutations, no response was observed in the PALB2 mutation carrier. MMC in this heavily previously treated PC was safe, with overall manageable grade 2 gastrointestinal toxicities including nausea and vomiting, and G3 hematological toxicities including anemia and thrombocytopenia. Pancreatic cancer patients with HRD may benefit from MMC treatment. Further clinical investigation of MMC in pancreatic cancer is warranted.

[Long-term response in advanced pancreatic adenocarcinoma - a case report and literature review]

BACKGROUND

Pancreatic cancer is still considered one of the most aggressive types of cancer and is associated with a very poor prognosis although there have been improvements in diagnostics and chemotherapy regimes in recent years. A cure can only be achieved through complete resection which is only possible when diagnosed at a very early stage, though this is rarely the case. We report on a patient with stage IV adenocarcinoma of the pancreas in which several therapeutically actionable mutations could be detected and discuss new options of targeted therapies.

CASE REPORT

A patient in his 50s was diagnosed with metastatic adenocarcinoma of the pancreas. The patient showed an excellent response to platinum-based chemotherapy with FOLFIRINOX. When a germline mutation in the BRCA-2 gene could be identified, he took part in the POLO-study receiving a maintenance therapy with the PARP-Inhibitor Olaparib. Due to a relapse, 2nd and 3rd line chemotherapy regimens were applied with Gemcitabine combined with Nab-Paclitaxel and later with Erlotinib. Although an activating mutation in the KRAS-gene could be detected as well, the patient rejected further experimental treatment.

CONCLUSION

Identifying predictive factors and specific targetable mutations in patients with advanced pancreatic cancer is needed to be able to apply more individual and specific therapies in order to improve outcomes.

PARPis and Other Novel, Targeted Therapeutics in Pancreatic Adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) has a poor prognosis, with a mere ∼10% of patients in the United States surviving 5 years from the time of diagnosis. Until recently, the treatment for advanced PDAC differed little based on patient or tumor characteristics. However, recent breakthroughs have identified subgroups of patients who benefit from novel, biomarker-driven therapies. We review the data and role for PARP inhibitors and for other biomarker-directed therapies, including for patients with NTRK fusions, NRG1 fusions, mismatch repair deficiency, and KRAS p.G12C mutations.

The Role of the Microbiome in Pancreatic Cancer

Simple Summary

Pancreatic cancer is deadly cancer characterized by dense stroma creating an immunosuppressive tumor microenvironment. Accumulating evidences indicate that the microbiome plays an important role in pancreatic cancer development and progression via the local and systemic inflammation and immune responses. The alteration of the microbiome modulates the tumor microenvironment and immune system in pancreatic cancer, which affects the efficacy of chemotherapies including immune-targeted therapies. Understanding the role of microbiome and underlying mechanisms may lead to novel biomarkers and therapeutic strategies for pancreatic cancer. This review summarizes the current evidence on the role of the microbiome in pancreatic cancer.

Abstract

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal malignancies, with little improvement in outcomes in recent decades, although the molecular and phenotypic characterization of PDAC has contributed to advances in tailored therapies. PDAC is characterized by dense stroma surrounding tumor cells, which limits the efficacy of treatment due to the creation of a physical barrier and immunosuppressive environment. Emerging evidence regarding the microbiome in PDAC implies its potential role in the initiation and progression of PDAC. However, the underlying mechanisms of how the microbiome affects the local tumor microenvironment (TME) as well as the systemic immune system have not been elucidated in PDAC. In addition, therapeutic strategies based on the microbiome have not been established. In this review, we summarize the current evidence regarding the role of the microbiome in the development of PDAC and discuss a possible role for the microbiome in the early detection of PDAC in relation to premalignant pancreatic diseases, such as chronic pancreatitis and intraductal papillary mucinous neoplasm (IPMN). In addition, we discuss the potential role of the microbiome in the treatment of PDAC, especially in immunotherapy, although the biomarkers used to predict the efficacy of immunotherapy in PDAC are still unknown. A comprehensive understanding of tumor-associated immune responses, including those involving the microbiome, holds promise for new treatments in PDAC.

Therapeutic advances in metastatic pancreatic cancer: a focus on targeted therapies

Mortality from pancreatic ductal adenocarcinoma (PDAC) is increasing worldwide and effective new treatments are urgently needed. The current treatment of metastatic PDAC in fit patients is based on two chemotherapy combinations (FOLFIRINOX and gemcitabine plus nab-paclitaxel) which were validated more than 8 years ago. Although almost all treatments targeting specific molecular alterations have failed so far when administered to unselected patients, encouraging results were observed in the small subpopulations of patients with germline BRCA 1/2 mutations, and somatic gene fusions (neurotrophic tyrosine receptor kinase, Neuregulin 1, which are enriched in KRAS wild-type PDAC), KRAS G12C mutations, or microsatellite instability. While targeted tumor metabolism therapies and immunotherapy have been disappointing, they are still under investigation in combination with other drugs. Optimizing pharmacokinetics and adapting available chemotherapies based on molecular signatures are other promising avenues of research. This review evaluates the current expectations and limits of available treatments and analyses the existing trials. A permanent search for actionable vulnerabilities in PDAC tumor cells and microenvironments will probably result in a more personalized therapeutic approach, keeping in mind that supportive care must also play a major role if real clinical efficacy is to be achieved in these patients.

Role of genetic testing in hepatic, pancreatic, and biliary cancers

Hepatic, pancreatic, and biliary (HPB) cancers, including hepatocellular carcinoma (HCC), pancreatic ductal adenocarcinoma (PDAC), and cholangiocarcinoma (CCA) cause a disproportionate amount of the global cancer-related mortality. Despite advances in surgical technique and improved systemic therapies, overall 5-year survival remains dismal, especially for patients with pancreatic and biliary cancer. Historically, systemic therapies for patients with HPB cancers were administered in a "one-size-fits-all" approach due to limited reliable data on efficacy for specific patient populations. However, recent advances in genetic testing techniques have greatly improved our understanding of HPB oncogenesis, shedding light on specific genetic mutations responsible for progression from physiologic cellular regulation to uninhibited cellular replication and invasive cancer. Investigations into the oncogenesis of HPB cancers have revealed multiple actionable genetic variants, as well as increased susceptibilities to currently available systemic therapies. For example, patients with PDAC and a known BRCA mutation are more likely to benefit from FOLFIRINOX or gemcitabine plus cisplatin. While patients with CCA and a IDH1 mutation may benefit from ivosidenib. As a result, many national and societal guidelines now recommend some form of genetic testing in the workup of patients with HPB cancers. We herein review the role of genetic testing in these aggressive cancers including DNA sequencing techniques, clinically relevant mutations, therapeutic implications, and current clinical recommendations.

The Evolving Paradigm of Germline Testing in Pancreatic Ductal Adenocarcinoma and Implications for Clinical Practice

Identification of deleterious germline mutations in pancreatic ductal adenocarcinoma (PDAC) patients can have therapeutic implications for the patients and result in cascade testing and prevention in their relatives. Universal testing for germline mutations is now considered standard of care in patients with PDAC, regardless of family history, personal history, or age. Here, we highlight the commonly identified germline mutations in PDAC patients as well as the impact of multigene panel testing. We further discuss therapeutic implications of germline testing on the index cases, and the impact of cascade testing on cancer early detection and prevention in relatives.

Combination immunotherapy for pancreatic cancer: challenges and future considerations

INTRODUCTION

: Immune checkpoint inhibitors (ICI) have not yielded significant efficacy in pancreatic ductal adenocarcinoma (PDA), despite the role of the innate and adaptive immune systems on progression and survival. However, recently identified pathways have identified new targets and generated promising clinical investigations into promoting an effective immune-mediated antitumor response in PDA.

AREAS COVERED

: We review biological mechanisms associated with immunotherapy resistance and outline strategies for therapeutic combinations with established and novel therapies in PDA.

EXPERT OPINION

: Pancreatic cancers rarely benefits from treatment with ICI due to an immunosuppressive tumor microenvironment (TME). New understandings of factors associated with the suppressive TME, include low and poor quality neoantigens, constrained effector T cells infiltration, and the presence of a dense, suppressive myeloid cell population. These findings have been translated into new clinical investigations evaluating novel therapies in combination with ICI and/or standard systemic chemotherapy and radiotherapy. The epithelial, immune, and stromal compartments are intricately related in PDA, and the framework for successful targeting of this disease requires a comprehensive and personalized approach.

Clinical Strategies Targeting the Tumor Microenvironment of Pancreatic Ductal Adenocarcinoma

Pancreatic cancer has a complex tumor microenvironment which engages in extensive crosstalk between cancer cells, cancer-associated fibroblasts, and immune cells. Many of these interactions contribute to tumor resistance to anti-cancer therapies. Here, new therapeutic strategies designed to modulate the cancer-associated fibroblast and immune compartments of pancreatic ductal adenocarcinomas are described and clinical trials of novel therapeutics are discussed. Continued advances in our understanding of the pancreatic cancer tumor microenvironment are generating stromal and immune-modulating therapeutics that may improve patient responses to anti-tumor treatment.

Homologous Recombination Deficiency Scar: Mutations and Beyond-Implications for Precision Oncology

Homologous recombination deficiency (HRD) is a prevalent in approximately 17% of tumors and is associated with enhanced sensitivity to anticancer therapies inducing double-strand DNA breaks. Accurate detection of HRD would therefore allow improved patient selection and outcome of conventional and targeted anticancer therapies. However, current clinical assessment of HRD mainly relies on determining germline BRCA1/2 mutational status and is insufficient for adequate patient stratification as mechanisms of HRD occurrence extend beyond functional BRCA1/2 loss. HRD, regardless of BRCA1/2 status, is associated with specific forms of genomic and mutational signatures termed HRD scar. Detection of this HRD scar might therefore be a more reliable biomarker for HRD. This review discusses and compares different methods of assessing HRD and HRD scar, their advances into the clinic, and their potential implications for precision oncology.

The CCTG PA.7 phase II trial of gemcitabine and nab-paclitaxel with or without durvalumab and tremelimumab as initial therapy in metastatic pancreatic ductal adenocarcinoma

Immunotherapy-based monotherapy treatment in metastatic pancreatic ductal adenocarcinoma (mPDAC) has shown limited benefit outside of the mismatch repair deficiency setting, while safety and efficacy of combining dual-checkpoint inhibitor immunotherapy with chemotherapy remains uncertain. Here, we present results from the CCTG PA.7 study (NCT02879318), a randomized phase II trial comparing gemcitabine and nab-paclitaxel with and without immune checkpoint inhibitors durvalumab and tremelimumab in 180 patients with mPDAC. The primary endpoint was overall survival. Secondary endpoints included progression-free survival and objective response rate. Results of the trial were negative as combination immunotherapy did not improve survival among the unselected patient population (p = 0.72) and toxicity was limited to elevation of lymphocytes in the combination immunotherapy group (p = 0.02). Exploratory baseline circulating tumor DNA (ctDNA) sequencing revealed increased survival for patients with KRAS wildtype tumors in both the combination immunotherapy (p = 0.001) and chemotherapy (p = 0.004) groups. These data support the utility of ctDNA analysis in PDAC and the prognostic value of ctDNA-based KRAS mutation status.

Moving the Needle on Precision Medicine in Pancreatic Cancer

The management of pancreatic ductal adenocarcinoma (PDAC) has posed a considerable challenge for decades, with incidence and mortality rates almost mirroring each other. Despite this, a deeper understanding of the complex biology inherent to PDAC has provided a roadmap for a more precise approach to treatment. PDAC deficient in homologous recombination repair and mismatch repair is a subgroup that should be identified in the clinic for a targeted approach. In addition, KRAS wild-type PDAC, occurring in approximately 10% of patients, is enriched in highly actionable alterations including fusions, underscoring the importance of integrative germline and somatic sequencing. Comprehensive sequencing efforts over the past decade have documented genomic- and transcriptomic-based classifiers, with the latter emerging as two main subtypes: the classical and basal-like, which are now being evaluated in clinical trials. Together with promising, innovative strategies to target KRAS mutations and their pleotropic effects, a new era of precision medicine in PDAC is on the horizon.

Clinical applications of mass spectrometry-based proteomics in cancer: where are we?

Tumor tissue processing methodologies in combination with data-independent acquisition mass spectrometry (DIA-MS) have emerged that can comprehensively analyze the proteome of multiple tumor samples accurately and reproducibly. Increasing recognition and adoption of these technologies has resulted in a tranche of studies providing novel insights into cancer classification systems, functional tumor biology, cancer biomarkers, treatment response and drug targets. Despite this, with some limited exceptions, MS-based proteomics has not yet been implemented in routine cancer clinical practice. Here, we summarize the use of DIA-MS in studies that may pave the way for future clinical cancer applications, and highlight the role of alternative MS technologies and multi-omic strategies. We discuss limitations and challenges of studies in this field to date and propose steps for integrating proteomic data into the cancer clinic. This article is protected by copyright. All rights reserved.

Neoadjuvant chemotherapy or upfront surgery in localized pancreatic cancer: a contemporary analysis

Neoadjuvant chemotherapy is considered a new treatment option for potentially resectable pancreatic cancer. However, data are not well established on overall survival and delaying surgery in resectable pancreatic cancer, as well as on those patients that ultimately cannot undergo surgery. We analyzed pancreatic cancer patients treated in a tertiary hospital from January 2016 to December 2020. Patients with resectable stage I and II pancreatic cancer were evaluated regarding surgery, neoadjuvant treatment, and other clinical demographics. The survival function was estimated using the Kaplan–Meier method, and the relationship between the variables of interest and the overall survival (OS) was assessed by adopting the proportional regression Cox models. A total of 216 patients were evaluated. 81 of them with resectable/borderline resectable disease and 135 with unresectable /metastatic disease at diagnosis. Median OS for stage I and II disease were 36 and 28 months, respectively. For resectable pancreatic cancer median OS was 28 months, for borderline resectable pancreatic cancer median OS was 11 months. Median OS for stage III (locally advanced) and stage IV (metastatic) were 10 and 7 months, respectively (p < 0.0001). Median OS of 9 months were obtained for patients with stage I and II that did not undergo surgery compared to 25 months in patients that underwent surgery in any time (p < 0.001). Comparing patients with localized disease, median OS for patients treated with upfront surgery was 28 months, compared to 15 months in patients treated with neoadjuvant approach (p = 0.04). Most patients that did not undergo surgery have decline of performance status or disease progression on neoadjuvant treatment. On multivariable analysis in pancreatic cancer stages I and II, including age, sex, borderline or resectable disease, CA 19–9, positive lymph nodes and neoadjuvant treatment, the surgery was the only factor associated with improved overall survival (p = 0.04). Upfront surgery should still be considered a standard of care approach for resectable pancreatic cancer. Biomarker driven studies and randomized trials with combination therapies are necessary to address neoadjuvant chemotherapy and delaying surgery in purely resectable pancreatic cancer.

Association Between Family History and Risk of Pancreatic Cancer in Patients With BRCA1 and BRCA2 Pathogenic Variants

OBJECTIVES

Current guidelines limit pancreatic cancer screening to those BRCA1/2 patients who have a family history of pancreatic cancer. We aimed to assess the association between family history and risk of pancreatic neoplasms in BRCA1/2 patients.

METHODS

We reviewed medical records of BRCA1/2 patients followed at our institution between 1995 and 2020. Family history was defined as those with a first-degree relative with pancreatic cancer. We compared the incidence and prevalence of pancreatic neoplasms between patients with and without family history of pancreatic cancer.

RESULTS

We identified 56 BRCA1/2 patients with family history and 238 without family history of pancreatic cancer. No difference between these groups was noted in age, race, or sex. Mean follow-up interval for BRCA1/2 patients was 4.6 years (range, 0-19.7 years). There was no significant difference in prevalence (19.6% vs 12.6; P = 0.3) or incidence (29% vs 14.1%; P = 0.08) of branch-duct intraductal papillary mucinous neoplasm between the 2 groups. No association between family history and pancreatic cancer risk was noted. Only 1 of 10 BRCA1/2 patients with pancreatic cancer had a family history.

CONCLUSIONS

Our results do not support using family history to determine eligibility for pancreatic cancer screening.

Oncology clinic-based germline genetic testing for exocrine pancreatic cancer enables timely return of results and unveils low uptake of cascade testing

BACKGROUND

Traditional medical genetics models are unable to meet the growing demand for germline genetic testing (GT) in patients with exocrine pancreatic cancer (PC). This study investigates the impact of an ambulatory oncology clinic-based GT model.

METHODS

From 2012 to 2021, patients with PC were prospectively enrolled and considered for GT. Two chronological cohorts were compared: (1) the preuniversal genetic testing (pre-UGT) cohort, which received GT based on clinical criteria or family history; and (2) the post-UGT cohort, where an 86-gene panel was offered to all patients with PC.

RESULTS

Of 847 eligible patients, 735 (86.8%) were enrolled (pre-UGT, n=579; post-UGT, n=156). A higher proportion of the post-UGT cohort received prospective GT (97.4% vs 58.5%, p<0.001). The rate of pathogenic germline alterations (PGA) across both cohorts was 9.9%, with 8.0% of PGAs in PC susceptibility genes. The post-UGT cohort had a higher prevalence of overall PGAs (17.2% vs 6.6%, p<0.001) and PGAs in PC susceptibility genes (11.9% vs 6.3%, p<0.001). The median turnaround time from enrolment to GT report was shorter in the post-UGT cohort (13 days vs 42 days, p<0.001). Probands with a PGA disclosed their GT results to 84% of their first-degree relatives (FDRs). However, only 31% of informed FDRs underwent GT, and the number of new cases per index case was 0.52.

CONCLUSION

A point-of-care GT model is feasible and expedites access to GT for patients with PC. Strategies to increase the uptake of cascade testing are needed to maximise the clinical impact of an oncology clinic-based GT model.

Pancreatic Cancer: Pathogenesis, Screening, Diagnosis, and Treatment

Pancreatic ductal adenocarcinoma (PDAC) is a clinically challenging cancer, due to both its late stage at diagnosis and its resistance to chemotherapy. However, recent advances in our understanding of the biology of PDAC have revealed new opportunities for early detection and targeted therapy of PDAC. In this review, we discuss the pathogenesis of PDAC, including molecular alterations in tumor cells, cellular alterations in the tumor microenvironment, and population-level risk factors. We review the current status of surveillance and early detection of PDAC, including populations at high risk and screening approaches. We outline the diagnostic approach to PDAC and highlight key treatment considerations, including how therapeutic approaches change with disease stage and targetable subtypes of PDAC. Recent years have seen significant improvements in our approaches to detect and treat PDAC, but large-scale, coordinated efforts will be needed to maximize the clinical impact for patients and improve overall survival.

Germline variants in cancer-predisposing genes in pancreatic cancer patients with a family history of cancer

BACKGROUND

Our phase II trial (FABRIC study) failed to verify the efficacy of gemcitabine plus oxaliplatin (GEMOX) in patients with pancreatic ductal adenocarcinoma (PDAC) with a familial or personal history of pancreatic, breast, ovarian or prostate cancer, which suggested that a family and personal history may be insufficient to determine response to platinum-based chemotherapy.

METHODS

This ancillary analysis aimed to investigate the prevalence of germline variants of homologous recombination repair (HRR)-related genes and clarify the association of germline variants with the efficacy of GEMOX and patient outcome in PDAC patients. Of 45 patients enrolled in FABRIC study, 27 patients were registered in this ancillary analysis.

RESULTS

Of the identified variants in HRR-related genes, one variant was considered pathogenic and eight variants in six patients (22%) were variants of unknown significance (VUS). Objective response to GEMOX was achieved by 43% of the seven patients and tended to be higher than that of patients without such variants (25%). Pathogenic/VUS variant in HRR-related genes was an independent favorable factor for progression-free survival (hazard ratio, 0.322; P = 0.047) and overall survival (hazard ratio, 0.195; P = 0.023) in multivariable analysis.

CONCLUSIONS

The prevalence of germline variants in PDAC patients was very low even among patients with a familial/personal history of pancreatic, breast, ovarian or prostate cancer. Patients with one or more germline variants in HRR-related genes classified as pathogenic or VUS may have the potential to obtain better response to GEMOX and have better outcomes.

Is Cell-Free DNA Testing in Pancreatic Ductal Adenocarcinoma Ready for Prime Time?

Simple Summary

Pancreatic cancer is a deadly cancer with limited treatment options. It is often detected in most people at stages where cure is not possible. There is no good test to know if a person will respond to treatment or if there is any disease beyond what can be seen by available imaging tests. Genetic material from the tumor is expected to float in the blood. Studying the alterations in the genetic material could help detect the tumor early, give an idea about its aggressiveness and response to available treatments, and facilitate the discovery of newer therapies. The focus of the studies so far has been on only one kind of genetic aberration, mutations, which has not given us great results. There is a need to explore another type of change known as methylation that could hold answers for managing pancreatic cancers better.

Abstract

Cell-free DNA (cfDNA) testing currently does not have a significant role in PDA management: it is insufficient to diagnose PDA, and its use is primarily restricted to identifying targetable mutations (if tissue is insufficient or unavailable). cfDNA testing has the potential to address critical needs in PDA management, such as pre-operative risk stratification (POR), prognostication, and predicting (and monitoring) treatment response. Prior studies have focused primarily on somatic mutations, specifically KRAS variants, and have shown limited success in addressing prognosis and POR. Recent studies have demonstrated the importance of other less prevalent mutations (ERBB2 and TP53), but no studies have provided reliable mutation panels for clinical use. Methylation aberrations in cfDNA (epigenetic markers) in PDA have been relatively less explored. However, early evidence has suggested they offer diagnostic and, to some extent, prognostic value. The inclusion of epigenetic markers of cfDNA adds another dimension to genomic testing and may open new therapeutic avenues beyond addressing critical areas of need in PDA treatment. For cfDNA to substantially influence PDA management, concerted efforts are required to include less frequent mutations and epigenetic markers. Furthermore, relying on KRAS mutations for PDA management will always be inadequate.

Germline Aberrations in Pancreatic Cancer: Implications for Clinical Care

Pancreatic ductal adenocarcinoma (PDAC) has an extremely poor prognosis and represents a major public health issue, as both its incidence and mortality are expecting to increase steeply over the next years. Effective screening strategies are lacking, and most patients are diagnosed with unresectable disease precluding the only chance of cure. Therapeutic options for advanced disease are limited, and the treatment paradigm is still based on chemotherapy, with a few rare exceptions to targeted therapies. Germline variants in cancer susceptibility genes-particularly those involved in mechanisms of DNA repair-are emerging as promising targets for PDAC treatment and prevention. Hereditary PDAC is part of the spectrum of several syndromic disorders, and germline testing of PDAC patients has relevant implications for broad cancer prevention. Germline aberrations in BRCA1 and BRCA2 genes are predictive biomarkers of response to poly(adenosine diphosphate-ribose) polymerase (PARP) inhibitor olaparib and platinum-based chemotherapy in PDAC, while mutations in mismatch repair genes identify patients suitable for immune checkpoint inhibitors. This review provides a timely and comprehensive overview of germline aberrations in PDAC and their implications for clinical care. It also discusses the need for optimal approaches to better select patients for PARP inhibitor therapy, novel therapeutic opportunities under clinical investigation, and preclinical models for cancer susceptibility and drug discovery.

Early-onset pancreatic cancer: a review of molecular mechanisms, management, and survival

OBJECTIVES

Early-onset pancreatic cancer (EOPC) - defined as pancreatic cancer diagnosed before the age of 50 years - is associated with a poor prognosis as compared to later-onset pancreatic cancer (LOPC). Emerging evidence suggests that EOPC may exhibit a genetic signature and tumor biology that is distinct from that of LOPC. We review genetic mutations that are more prevalent in EOPC relative to LOPC and discuss the potential impact of these mutations on treatment and survival.

MATERIALS AND METHODS

Using PubMed and Medline, the following terms were searched and relevant citations assessed: "early onset pancreatic cancer," "late onset pancreatic cancer," "pancreatic cancer," "pancreatic cancer genes," and "pancreatic cancer targeted therapy."

RESULTS

Mutations in CDKN2, FOXC2, and SMAD4 are significantly more common in EOPC as compared to LOPC. In addition, limited data suggest that PI3KCA mutations are more frequently observed in EOPC as compared to LOPC. KRAS mutations are relatively rare in EOPC.

CONCLUSIONS

Genetic mutations associated with EOPC are distinct from those of LOPC. The preponderance of the evidence suggest that poor outcomes in EOPC are related both to advanced stage of presentation and unique tumor biology. The molecular and genetic features of EOPC warrant further investigation in order to optimize management.

The Homologous Recombination Deficiency Scar in Advanced Cancer: Agnostic Targeting of Damaged DNA Repair

Simple Summary

Tumor-suppressor genes are involved in DNA break repair through the homologous recombination system and are widely known for their role in hereditary cancer. Beyond breast and ovarian cancer, prostate and pancreatic cancer also have targetable homologous recombination deficiency (HRD) beyond the well-known BRCA1 and BRCA2 with relevance that exceeds diagnostic purposes. In this review, we aim to summarize the roles of HRD across tumor types and the treatment landscape to guide the targeting of damaged DNA repair based on the cancer’s genetic features.

Abstract

BRCA1 and BRCA2 are the most recognized tumor-suppressor genes involved in double-strand DNA break repair through the homologous recombination (HR) system. Widely known for its role in hereditary cancer, HR deficiency (HRD) has turned out to be critical beyond breast and ovarian cancer: for prostate and pancreatic cancer also. The relevance for the identification of these patients exceeds diagnostic purposes, since results published from clinical trials with poly-ADP ribose polymerase (PARP) inhibitors (PARPi) have shown how this type of targeted therapy can modify the long-term evolution of patients with HRD. Somatic aberrations in other HRD pathway genes, but also indirect genomic instability as a sign of this DNA repair impairment (known as HRD scar), have been reported to be relevant events that lead to more frequently than expected HR loss of function in several tumor types, and should therefore be included in the current diagnostic and therapeutic algorithm. However, the optimal strategy to identify HRD and potential PARPi responders in cancer remains undefined. In this review, we summarize the role and prevalence of HRD across tumor types and the current treatment landscape to guide the agnostic targeting of damaged DNA repair. We also discuss the challenge of testing patients and provide a special insight for new strategies to select patients who benefit from PARPi due to HRD scarring.