Overall survival and clinical characteristics of BRCA mutation carriers with stage I/II pancreatic cancer

Pancreatic cancer biomarkers: A pathway to advance in personalized treatment selection

Pancreatic cancer is one of the tumors with the worst prognosis, and unlike other cancers, few advances have been made in recent years. The only curative option is surgery, but only 15-20% of patients are candidates, with a high risk of relapse. In advanced pancreatic cancer there are few first-line treatment options and no validated biomarkers for better treatment selection. The development of targeted therapies in pancreatic cancer is increasingly feasible due to tumor-agnostic treatments, such as PARP inhibitors in patients with BRCA1, BRCA2 or PALB2 alterations or immunotherapies in patients with high microsatellite instability/tumor mutational burden. In addition, other therapeutic molecules have been developed for patients with KRAS G12C mutation or fusions in NTRK or NRG1. Consequently, there has been a growing interest in biomarkers that may help guide targeted therapy in pancreatic cancer. Therefore, this review aims to offer an updated perspective on biomarkers with therapeutic potential in pancreatic cancer.

Advances in artificial intelligence for the diagnosis and treatment of ovarian cancer (Review)

Artificial intelligence (AI) has emerged as a crucial technique for extracting high‑throughput information from various sources, including medical images, pathological images, and genomics, transcriptomics, proteomics and metabolomics data. AI has been widely used in the field of diagnosis, for the differentiation of benign and malignant ovarian cancer (OC), and for prognostic assessment, with favorable results. Notably, AI‑based radiomics has proven to be a non‑invasive, convenient and economical approach, making it an essential asset in a gynecological setting. The present study reviews the application of AI in the diagnosis, differentiation and prognostic assessment of OC. It is suggested that AI‑based multi‑omics studies have the potential to improve the diagnostic and prognostic predictive ability in patients with OC, thereby facilitating the realization of precision medicine.

Targeting BRCA and PALB2 in Pancreatic Cancer

OPINION STATEMENT

An important subgroup of pancreatic ductal adenocarcinomas (PDACs) harbor pathogenic variants in BRCA1, BRCA2, or PALB2. These tumors are exquisitely sensitive to platinum-based chemotherapy and patients may experience deep and durable responses to this treatment. PARP inhibitors offer potential respite from the cumulative toxicities of chemotherapy as they significantly extend progression-free survival compared to a chemotherapy holiday. Given the lack of proven survival benefit, the decision to use a maintenance PARP inhibitor rather than continue chemotherapy should be individualized. Interestingly, in both published clinical trials of maintenance PARP inhibitors, there is a striking range of interpatient benefit: Even in the platinum-sensitive setting, roughly 25% of tumors appear to be PARP inhibitor refractory (progressive disease within 2 months of starting treatment), 50% sustain moderate benefit (up to 2 years), and 25% are hyper-responsive (more than 2 years of benefit). This finding highlights the need to refine our understanding of which patients will respond to maintenance PARP inhibitors, both by being able to identify biallelic loss and by deepening our knowledge of resistance mechanisms and who develops them. Recent data supports that reversion mutations are common in PARP inhibitor refractory patients, but we have little understanding of the mechanisms that drive delayed resistance and long-term responses. Identifying which patients are more prone to certain mechanisms of resistance and tackling them with specific treatment strategies are areas of active investigation. Additionally, given that PARP inhibitors have limited overall efficacy for most patients, upfront combination strategies are an important future strategy.

Understanding the Genetic Landscape of Pancreatic Ductal Adenocarcinoma to Support Personalized Medicine: A Systematic Review

Pancreatic ductal adenocarcinoma (PDAC) is one of the most fatal malignancies worldwide. While population-wide screening recommendations for PDAC in asymptomatic individuals are not achievable due to its relatively low incidence, pancreatic cancer surveillance programs are recommended for patients with germline causative variants in PDAC susceptibility genes or a strong family history. In this study, we sought to determine the prevalence and significance of germline alterations in major genes (ATM, BRCA1, BRCA2, CDKN2A, EPCAM, MLH1, MSH2, MSH6, PALB2, PMS2, STK11, TP53) involved in PDAC susceptibility. We performed a systematic review of PubMed publications reporting germline variants identified in these genes in PDAC patients. Overall, the retrieved articles included 1493 PDAC patients. A high proportion of these patients (n = 1225/1493, 82%) were found to harbor alterations in genes (ATM, BRCA1, BRCA2, PALB2) involved in the homologous recombination repair (HRR) pathway. Specifically, the remaining PDAC patients were reported to carry alterations in genes playing a role in other cancer pathways (CDKN2A, STK11, TP53; n = 181/1493, 12.1%) or in the mismatch repair (MMR) pathway (MLH1, MSH2, MSH6, PMS2; n = 87/1493, 5.8%). Our findings highlight the importance of germline genetic characterization in PDAC patients for better personalized targeted therapies, clinical management, and surveillance.

DNA damage repair mutations in pancreatic cancer- prognostic or predictive?

Objective

The efficacy of platinum-based chemotherapy (PtCh) for pancreatic cancer (PC) patients with DNA damage repair gene mutations (DDRm) compared to those without DDRm remains uncertain.

Methods

After a thorough database searching in PubMed, Embase, and Web of Science, a total of 19 studies that met all the inclusion criteria were identified. The primary outcomes were overall survival (OS) and progression-free survival (PFS) for PC patients with DDRm versus those without DDRm after PtCh.

Results

Patients with advanced-stage PC who have DDRm tend to have longer OS compared to patients without DDRm, regardless of their exposure to PtCh (HR=0.63; I2 = 66%). Further analyses indicated that the effectiveness of PtCh for OS was modified by DDRm (HR=0.48; I2 = 59%). After the first- line PtCh (1L-PtCh), the PFS of advanced-stage PC with DDRm was also significantly improved (HR=0.41; I2 = 0%). For patients with resected PC, regardless of their exposure to PtCh, the OS for patients with DDRm was comparable to those without DDRm (HR=0.82; I2 = 71%). Specifically, for patients with resected PC harboring DDRm who received PtCh (HR=0.85; I2 = 65%) and for those after non-PtCh (HR=0.87; I2 = 0%), the presence of DDRm did not show a significant association with longer OS.

Conclusion

1L-PtCh treatment is correlated with favorable survival for advanced-stage PC patients with DDRm. For resected-stage PC harboring DDRm, adjuvant PtCh had limited effectiveness. The prognostic value of DDRm needs to be further verified by prospective randomized controlled trials.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42022302275.

Heterogeneous tumor microenvironment in pancreatic ductal adenocarcinoma: An emerging role of single-cell analysis

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest malignancies in the world, for which the mortality is almost as high as the disease incidence and is predicted to be the second-highest cause of cancer-related deaths by 2030. These cancerous tumors consist of diversified gene expressions within the different cellular subpopulations that include neoplastic ductal cells, cancer-associated fibroblasts, and immune cells, all of which collectively facilitate cellular heterogeneity in the PDAC tumor microenvironment (TME). Active intratumoral interaction within the cell populations in TME induces the proliferation of cancerous cells, accounting for tumorigenesis and rapid metastasis.

METHODS

This review will focus on novel findings uncovering PDAC heterogeneity in different cellular subpopulations using single-cell RNA-sequencing (scRNA-seq) and other single-cell analysis technologies. It will further explore the emerging role of single-cell technologies in assessing the role of different subpopulations of neoplastic ductal cells, cancer-associated fibroblasts, and immune cells in PDAC progression.

RESULTS AND CONCLUSION

The application of scRNA-seq in PDAC has started to unveil associations between disease progression and heterogeneity in pancreatic TME and could influence future PDAC treatment. Recent advances in scRNA-seq have uncovered comprehensive analyses of heterogeneous ecosystems present within the TME. These emerging findings underpins further need for a more in-depth understanding of intratumoral heterogeneity in the PDAC microenvironment.

It Is All in the Genes: A Story of Unexpected Survival in a 67-Year-Old Male with Metastatic Pancreatic Cancer

Background

We describe a case report of a 67-year-old male with PDAC who experienced an exceptional survival outcome during systemic therapy and its implications in precision medicine. We hypothesize that his outcomes are attributable, in part, to a germline BRCA2 deletion and somatic GNAS substitution.

Methods

Retrospective single-patient chart review was performed at the London Regional Cancer Program, as well as a structured literature search spanning all years in PubMed of BRCA and GNAS mutations in pancreatic cancer.

Results

The case described herein represents a 67-year-old male who survived over 27 months after third-line treatment with gemcitabine, docetaxel, and capecitabine (GTX) chemotherapy for metastatic PDAC after progression on gemcitabine and Abraxane and then on FOLFIRINOX. His survival far exceeded the median overall survival metrics. Genetic testing revealed a pathogenic heterozygous germline BRCA2 6643delT p.(Tyr2215Thrfs∗14) frameshift mutation and somatic GNAS 2531G > A p.(Arg844His) mutation.

Conclusions

This case highlights the urgent need to expand our knowledge of cancer biology to advance personalized cancer treatment and therapy development.

Pancreatic Cancer: BRCA Targeted Therapy and Beyond

Pancreatic ductal adenocarcinoma (PDAC) is projected to become the second leading cause of cancer-related death in the US by 2030, despite accounting for only 5% of all cancer diagnoses. Germline gBRCA1/2-mutated PDAC represents a key subgroup with a favorable prognosis, due at least in part to additional approved and guideline-endorsed therapeutic options compared with an unselected PDAC cohort. The relatively recent incorporation of PARP inhibition into the treatment paradigm for such patients has resulted in renewed optimism for a biomarker-based approach to the management of this disease. However, gBRCA1/2 represents a small subgroup of patients with PDAC, and efforts to extend the indication for PARPi beyond BRCA1/2 mutations to patients with PDAC and other genomic alterations associated with deficient DNA damage repair (DDR) are ongoing, with several clinical trials underway. In addition, despite an array of approved therapeutic options for patients with BRCA1/2-associated PDAC, both primary and acquired resistance to platinum-based chemotherapies and PARPi presents a significant challenge in improving long-term outcomes. Herein, we review the current treatment landscape of PDAC for patients with BRCA1/2 and other DDR gene mutations, experimental approaches under investigation or in development, and future directions.

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.

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.

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.

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.

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.

Clinicopathological Significance of BRCAness in Resectable Pancreatic Ductal Adenocarcinoma and Its Association With Anticancer Drug Sensitivity in Pancreatic Cancer Cells

OBJECTIVE

The concept of BRCAness has been proposed as a homologous recombination repair dysfunction triggered by a genetic defect in the BRCA pathway including the BRCA1/2 mutations. A certain number of pancreatic ductal adenocarcinoma (PDAC) patients have BRCAness. However, a large-scale analysis of BRCAness in PDAC has not been performed. In addition, no basic studies have examined the significance of BRCAness in PDAC cell lines.

METHODS

Ninety-two patients who underwent surgery for PDAC were enrolled. Formalin-fixed and paraffin-embedded specimens of resected PDACs were used to analyze BRCAness by multiplex ligation-dependent probe amplification. We also analyzed BRCAness in pancreatic cancer cell lines and the sensitivity to cisplatin and olaparib using a colony formation assay.

RESULTS

Of the 92 patients with PDAC, 6 were detected to have BRCAness-positive PDAC (6.5%). No significant differences in overall survival and progression-free survival were observed between the BRCAness-positive and BRCAness-negative groups. One PDAC cell line, KP-2, was positive for BRCAness and was more sensitive to cisplatin and olaparib than the BRCAness-negative cell lines.

CONCLUSIONS

Our results revealed that a considerable number of PDACs are positive for BRCAness, suggesting that BRCAness status could be a useful biomarker for selecting anticancer treatments for advanced or relapsed PDAC.

BRCA 1/2 Germline Mutation Predicts the Treatment Response of FOLFIRINOX with Pancreatic Ductal Adenocarcinoma in Korean Patients

We evaluated the proportion of BRCA 1/2 germline mutations in Korean patients with sporadic pancreatic ductal adenocarcinoma (PDAC) and its effect on the chemotherapeutic response of FOLFIRINOX. This retrospective study included patients who were treated at two tertiary hospitals between 2012 and 2020, were pathologically confirmed to have PDAC, and had undergone targeted next-generation sequencing-based germline genetic testing. Sixty-six patients were included in the study (24 men; median age 57.5 years). In the germline test, BRCA 1/2 pathogenic mutations were found in nine patients (9/66, 13%, BRCA 1, n = 3; BRCA 2, n = 5; and BRCA 1/2, n = 1). There was no significant difference in the baseline characteristics according to BRCA mutation positivity. Among patients who underwent FOLFIRINOX chemotherapy, patients with a BRCA 1/2 mutation showed a higher overall response rate than those without a BRCA 1/2 mutation (71.4% vs. 13.9%, p = 0.004). Patients with a germline BRCA 1/2 mutation showed longer progression-free survival than those without a BRCA 1/2 mutation, without a significant time difference (18 months vs. 10 months, p = 0.297). Patients with a BRCA 1/2 mutation in the germline blood test had a higher response rate to FOLFIRINOX chemotherapy in PDAC. The high proportion of BRCA 1/2 germline mutations and response rate supports the need for germline testing in order to predict better treatment response.

BRCA-mutant pancreatic ductal adenocarcinoma

Despite continued research, pancreatic ductal adenocarcinoma (PDAC) remains one of the main causes of cancer death. Interest is growing in the role of the tumour suppressors breast cancer 1 (BRCA1) and BRCA2-typically associated with breast and ovarian cancer-in the pathogenesis of PDAC. Indeed, both germline and sporadic mutations in BRCA1/2 have been found to play a role in the development of PDAC. However, data regarding BRCA1/2-mutant PDAC are lacking. In this review, we aim to outline the specific landscape of BRCA-mutant PDAC, focusing on heritability, clinical features, differences between BRCA1 and 2 mutations and between germline and sporadic alterations, as well as established therapeutic strategies and those that are still under evaluation.

Mutations in key driver genes of pancreatic cancer: molecularly targeted therapies and other clinical implications

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal cancers, with a minimal difference between its incidence rate and mortality rate. Advances in oncology over the past several decades have dramatically improved the overall survival of patients with multiple cancers due to the implementation of new techniques in early diagnosis, therapeutic drugs, and personalized therapy. However, pancreatic cancers remain recalcitrant, with a 5-year relative survival rate of <9%. The lack of measures for early diagnosis, strong resistance to chemotherapy, ineffective adjuvant chemotherapy and the unavailability of molecularly targeted therapy are responsible for the high mortality rate of this notorious disease. Genetically, PDAC progresses as a complex result of the activation of oncogenes and inactivation of tumor suppressors. Although next-generation sequencing has identified numerous new genetic alterations, their clinical implications remain unknown. Classically, oncogenic mutations in genes such as KRAS and loss-of-function mutations in tumor suppressors, such as TP53, CDNK2A, DPC4/SMAD4, and BRCA2, are frequently observed in PDAC. Currently, research on these key driver genes is still the main focus. Therefore, studies assessing the functions of these genes and their potential clinical implications are of paramount importance. In this review, we summarize the biological function of key driver genes and pharmaceutical targets in PDAC. In addition, we conclude the results of molecularly targeted therapies in clinical trials and discuss how to utilize these genetic alterations in further clinical practice.

Targeting BRCA and DNA Damage Repair Genes in GI Cancers: Pathophysiology and Clinical Perspectives

Mutated germline alleles in the DNA damage repair (DDR) genes “breast cancer gene 1” (BRCA1) and BRCA2 have originally been identified as major susceptibility genes in breast and ovarian cancers. With the establishment and approval of more cost-effective gene sequencing methods, germline and somatic BRCA mutations have been detected in several cancers. Since the approval of poly (ADP)-ribose polymerase inhibitors (PARPi) for BRCA-mutated cancers, BRCA mutations gained rising therapeutic implications. The impact and significance of BRCA mutations have been evaluated extensively in the last decades. Moreover, other genes involved in the DDR pathway, such as ATM, ATR, or CHK1, have emerged as potential new treatment targets, as inhibitors of these proteins are currently under clinical investigation. This review gives a concise overview on the emerging clinical implications of mutations in the DDR genes in gastrointestinal cancers with a focus on BRCA mutations.

Genomic alterations in tumor tissue and ctDNA from Chinese pancreatic cancer patients

Though the genomic feature of pancreatic cancer has been comprehensively studied in western patients, the genetic feature of Chinese patients is poorly clarified. In this study, a total of 225 pancreatic cancer patients were enrolled, mainly pancreatic ductal adenocarcinoma (PDAC, 97.33%). 140 patients (62.22%) provided sufficient tumor tissues for genomic analysis, and the rest (37.78%) were provided serum instead. Utilizing target next-generation sequencing (NGS), we analyzed genomic alterations of 618 selected genes. Corresponding data in the TCGA database were also analyzed here. In total, 26 (11.61%) patients had pathogenic or likely pathogenic germline variants, mainly (84.62%) involved genes in the DNA damage repair (DDR) pathway. The mean and median counts of somatic alterations per sample were 6.28 and 5, respectively. The most frequently mutated genes in our cohort were KRAS, TP53, CDKN2A, SMAD4, FBXW7 and ARID1A, revealing a significantly different prevalence of genes including KRAS, CDKN2A, ARID1A, NOTCH1, ARID1B than the corresponding data in the TCGA database. 39.11% of patients were identified with actionable alteration and the ratio was not significantly different between tissue and serum samples. 22.67% of patients harbored DDR gene alterations, which were associated with a higher tumor mutation burden. We also found that all the DDR alterations were not correlated with the overall survival and immune and stroma score, but the changes in NK cells and follicular T cells were identified in samples with DDR changes according to TCGA database. In summary, we identified a distinct genomic feature of Chinese pancreatic cancer patients by comparing with the data in TCGA database, and suggested the role for genetic testing using tissue or ctDNA samples in decision-making process. DDR alterations were associated with a higher tumor mutation burden and the significantly higher counts of NK cells in DDR altered samples may raise the attention in future related drugs development.

Targeting DNA Damage Repair Mechanisms in Pancreas Cancer

Impaired DNA damage repair (DDR) is increasingly recognised as a hallmark in pancreatic ductal adenocarcinoma (PDAC). It is estimated that around 14% of human PDACs harbour mutations in genes involved in DDR, including, amongst others, BRCA1/2, PALB2, ATM, MSH2, MSH6 and MLH1. Recently, DDR intervention by PARP inhibitor therapy has demonstrated effectiveness in germline BRCA1/2-mutated PDAC. Extending this outcome to the significant proportion of human PDACs with somatic or germline mutations in DDR genes beyond BRCA1/2 might be beneficial, but there is a lack of data, and consequently, no clear recommendations are provided in the field. Therefore, an expert panel was invited by the European Society of Digestive Oncology (ESDO) to assess the current knowledge and significance of DDR as a target in PDAC treatment. The aim of this virtual, international expert meeting was to elaborate a set of consensus recommendations on testing, diagnosis and treatment of PDAC patients with alterations in DDR pathways. Ahead of the meeting, experts completed a 27-question survey evaluating the key issues. The final recommendations herein should aid in facilitating clinical practice decisions on the management of DDR-deficient PDAC.

Treatment opportunities and future perspectives for pancreatic cancer patients with germline BRCA1-2 pathogenic variants

Personalized treatments and predictive biomarkers of pancreatic cancer (PDAC) are still lacking. Recently germline mutations in BRCA 1 and 2 genes, leading to homologous repair deficiency, have emerged as new targets for more specific and effective therapies, exploiting the increased susceptibility to platinum salts and PARP inhibitors. In addition to BRCA, pathogenic variants in PALB2 and in other genes involved in the DNA damage response pathway (DDR) represent potential targets, as well as their respective somatic alterations. This enlarged molecularly-selected population sharing the BRCAness phenotype, is expected to show a higher sensibility to a number of DNA damaging agents and DDR inhibitors. However, the possibility of new therapeutic opportunities for DDR defective PDAC patients has to face the lack of solid evidence about the proper type and timing of targeted-treatments, the potential combination strategies and most importantly, the lack of informations on the functional impact of each specific pathogenic variant on the DDR pathway. This review summarizes the current and near-future options for the clinical management of PDAC patients harboring a DDR deficiency, analyzing the state of the art of the indications of platinum salts and other cytotoxic agents in the advanced and early stage PDAC, the development of PARP inhibitors and the rational for new combinations with immunotherapy and cycle checkpoint inhibitors, as well as the strategy to overcome the development of resistance over treatments.

Assistance by Routine CT Features Combined With 3D Texture Analysis in the Diagnosis of BRCA Gene Mutation Status in Advanced Epithelial Ovarian Cancer

Purpose

To evaluate the predictive value of routine CT features combined with 3D texture analysis for prediction of BRCA gene mutation status in advanced epithelial ovarian cancer.

Method

Retrospective analysis was performed on patients with masses occupying the pelvic space confirmed by pathology and complete preoperative images in our hospital, including 37 and 58 cases with mutant type and wild type BRCA, respectively (total: 95 cases). The enrolled patients’ routine CT features were analyzed by two radiologists. Then, ROIs were jointly determined through negotiation, and the ITK-SNAP software package was used for 3D outlining of the third-stage images of the primary tumor lesions and obtaining texture features. For routine CT features and texture features, Mann-Whitney U tests, single-factor logistic regression analysis, minimum redundancy, and maximum correlation were used for feature screening, and the performance of individual features was evaluated by ROC curves. Multivariate logistic regression analysis was used to further screen features, find independent predictors, and establish the prediction model. The established model’s diagnostic efficiency was evaluated by ROC curve analysis, and the histogram was obtained to conduct visual analysis of the prediction model.

Results

Among the routine CT features, the type of peritoneal metastasis, mesenteric involvement, and supradiaphragmatic lymph node enlargement were correlated with BRCA gene mutation (P < 0.05), whereas the location of the peritoneal metastasis (in the gastrohepatic ligament) was not significantly correlated with BRCA gene mutation (P > 0.05). Multivariate logistic regression analysis retained six features, including one routine CT feature and five texture features. Among them, the type of peritoneal metastasis was used as an independent predictor (P < 0.05), which had the highest diagnostic efficiency. Its AUC, accuracy, specificity, and sensitivity were 0.74, 0.79, 0.90, and 0.62, respectively. The prediction model based on the combination of routine CT features and texture features had an AUC of 0.86 (95% CI: 0.79–0.94) and accuracy, specificity, and sensitivity of 0.80, 0.76, and 0.81, respectively, indicating a better performance than that of any single feature.

Conclusions

Both routine CT features and texture features had value for predicting the mutation state of the BRCA gene, but their predictive efficiency was low. When the two types of features were combined to establish a predictive model, the model’s predictive efficiency was significantly higher than that of independent features.

Recent advances in precision medicine for pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is one of the leading causes of cancer mortality worldwide. Although advances in systemic chemotherapy for PDAC have improved survival outcomes for patients with the disease, chemoresistance is a major treatment issue for unselected PDAC patient populations. The existence of heterogeneity caused by a mixture of tumor cells and stromal cells produces chemoresistance and limits the targeted therapy of PDAC. Advances in precision medicine for PDACs according to the genetics and molecular biology of this disease may represent the next alternative approach to overcome the heterogeneity of different patients and improve survival outcomes for this poor prognostic disease. The genetic alteration of PDAC is characterized by four genes that are frequently mutated (KRAS, TP53, CDKN2A, and SMAD4). Furthermore, several genetic and molecular profiling studies have revealed that up to 25% of PDACs harbor actionable alterations. In particular, DNA repair dysfunction, including cases with BRCA mutations, is a causal element of sensitivity to platinum-based anti-cancer agents and poly-ADP ribose polymerase (PARP) inhibitors. A deep understanding of the molecular and cellular crosstalk in the tumor microenvironment helps to establish scientifically rational treatment strategies for cancers that show specific molecular profiles. Here, we review recent advances in genetic analysis of PDACs and describe future perspectives in precision medicine according to molecular subtypes or actionable gene mutations for patients with PDAC. We believe the breakthroughs will soon emerge to fight this deadly disease.

BRCA mutated pancreatic cancer: A change is coming

Pancreatic cancer remains a leading cause of cancer-related death with few available therapies for advanced disease. Recently, patients with germline BRCA mutations have received increased attention due to advances in the management of BRCA mutated ovarian and breast tumors. Germline BRCA mutations significantly increase risk of developing pancreatic cancer and can be found in up to 8% of patients with sporadic pancreatic cancer. In patients with germline BRCA mutations, platinum-based chemotherapies and poly (ADP-ribose) polymerase inhibitors are effective treatment options which may offer survival benefits. This review will focus on the molecular biology, epidemiology, and management of BRCA-mutated pancreatic cancer. Furthermore, we will discuss future directions for this area of research and promising active areas of research.

Biologic behavior of resected BRCA-mutated pancreatic cancer: Comparison with sporadic pancreatic cancer and other BRCA-related cancers

BACKGROUND

Since margin-negative resection is essential for the cure of pancreatic cancer (PC), early detection of PC is important. Although PC is the third most common cancer associated with BRCA1/2 mutations, clinical research regarding BRCA mutations in resected PC are rare. In this study, we investigated the oncologic characteristics of resected PC with BRCA mutation to suggest management strategies.

METHODS

We retrospectively reviewed data from 493 patients who were confirmed to be pathogenic BRCA1/2 mutation carriers between January 2007 and December 2019. We investigated the oncologic characteristics of PC patients by comparing them with resected sporadic PC and other BRCA-related cancer groups (breast cancer, ovarian cancer, and others).

RESULTS

Ten BRCA mutation carriers (2.0%) experienced PC, and PC onset was significantly later than that of BRCA-related breast cancer (age: breast vs. pancreas, 45.0 vs. 53.5 years, p = 0.050). Six patients underwent pancreatectomy and their long-term survival outcomes did not differ from those of sporadic PC patients (disease free survival: BRCA1/2 vs. sporadic, 10.0 months vs. 9.0 months, p = 0.504; overall survival: BRCA1/2 vs. sporadic, 29.0 months vs. 35.0 months, p = 0.520).

CONCLUSION

BRCA-mutated PC occurs later than BRCA-mutated breast cancer. Active genetic testing to identify BRCA1/2 mutation carriers at the onset of breast cancer and continuous long-term surveillance of these patients can provide opportunities to detect BRCA-mutated PC at a resectable stage.

An Emerging Paradigm for Germline Testing in Pancreatic Ductal Adenocarcinoma and Immediate Implications for Clinical Practice: A Review

Importance

Pancreatic ductal adenocarcinoma (PDAC) is a malignant neoplasm with a rising incidence and is a leading public health challenge. Pancreatic ductal adenocarcinoma has been well characterized genomically, with findings of therapeutic actionability that have substantive implications for clinical practice based on recent high-level evidence.

Observations

Pathogenic germline alterations (PGAs) are relatively common in individuals with PDAC, as evidenced in multiple recent data sets, with a frequency of approximately 10%. The most common PGAs are in BRCA1, BRCA2, and ATM and more rarely in PALB2, MLH1, MSH2, MSH6, PMS2, CDKN2A, and TP53, among others, with an aggregate frequency of 3.8% to 9.7%. These PGAs are of key interest owing to therapeutic actionability and the downstream identification of at-risk family members and possible hereditary cancer syndromes. Approximately 3% to 7% of individuals with PDAC harbor a BRCA1 or BRCA2 mutation, which are among the most frequently mutated genes in PDAC. Recent updates to the American Society of Clinical Oncology and the National Comprehensive Cancer Network guidelines recommend risk assessment for all individuals with PDAC irrespective of personal or family history or ethnicity. Treatment implications include the use of checkpoint inhibitor therapy for mismatch repair-deficient PDAC and the validation of poly-ADP (adenosine diphosphate)-ribose polymerase inhibitor (PARPi) therapy as a maintenance strategy in platinum-sensitive PDAC.

Conclusions and Relevance

With increasing evidence and slow improvement of outcomes, PDAC has entered the era of precision medicine. Germline mutations have been identified in key genes with an aggregate frequency of 3.8% to 9.7%, several of which are therapeutically actionable with platinum, PARPi, and checkpoint inhibitor therapy. Potential therapeutic targets need to be actively sought and identified.

BRCA in Gastrointestinal Cancers: Current Treatments and Future Perspectives

A strong association between pancreatic cancer and BRCA1 and BRCA2 mutations is documented. Based on promising results of breast and ovarian cancers, several clinical trials with poly (ADP-ribose) polymerase inhibitors (PARPi) are ongoing for gastrointestinal (GI) malignancies, especially for pancreatic cancer. Indeed, the POLO trial results provide promising and awaited changes for the pancreatic cancer therapeutic landscape. Contrariwise, for other gastrointestinal tumors, the rationale is currently only alleged. The role of BRCA mutation in gastrointestinal cancers is the subject of this review. In particular, we aim to provide the latest updates about novel therapeutic strategies that, exploiting DNA repair defects, promise to shape the future therapeutic scenario of GI cancers.

Effect of Germline Mutations in Homologous Recombination Repair Genes on Overall Survival of Patients with Pancreatic Adenocarcinoma

PURPOSE

To compare the clinical characteristics and overall survival (OS) of germline mutation carriers in homologous recombination repair (HRR) genes and noncarriers with pancreatic ductal adenocarcinoma (PDAC).

EXPERIMENTAL DESIGN

Germline DNA from 3,078 patients with PDAC enrolled in a prospective registry at Mayo Clinic between 2000 and 2017 was analyzed for mutations in 37 cancer predisposition genes. Characteristics and OS of patients with mutations in eight genes (ATM, BARD1, BRCA1, BRCA2, BRIP1, PALB2, RAD51C, and RAD51D) involved in HRR were compared with patients testing negative for mutations in all 37 genes.

RESULTS

The 175 HRR mutation carriers and 2,730 noncarriers in the study had a median duration of follow-up of 9.9 years. HRR mutation carriers were younger (median age at diagnosis: 63 vs. 66 years, P < 0.001) and more likely to have metastatic disease at diagnosis (46% vs. 36%, P = 0.004). In a multivariable model adjusting for sex, age at diagnosis, and tumor staging, patients with germline HRR mutations had a significantly longer OS compared with noncarriers [HR, 0.83; 95% confidence interval (CI), 0.70-0.97; P = 0.02]. Further gene-level analysis demonstrated that germline ATM mutation carriers had longer OS compared with patients without germline mutations in any of the 37 genes (HR, 0.72; 95% CI, 0.55-0.94; P = 0.01).

CONCLUSIONS

This study demonstrates that germline mutation carrier status in PDAC is associated with longer OS compared with noncarriers. Further research into tumor biology and response to platinum-based chemotherapy in germline mutation carriers with PDAC are needed to better understand the association with longer OS.

Efficacy of platinum-based chemotherapy and prognosis of patients with pancreatic cancer with homologous recombination deficiency: comparative analysis of published clinical studies

The aim of our study was to determine the effect of homologous recombination deficiency (HRD) on prognosis and efficacy of platinum-based chemotherapy in patients with pancreatic cancer (PC). We performed PubMed and Embase database queries. We included 4 studies into the meta-analysis and 16 studies in the systematic review. Our systematic analysis showed that the average weighted median overall survival (OS) in patients with HRD with advanced PC was 19.8 and 15.6 months in patients without HRD. With platinum-based chemotherapy, the average weighted median OS in patients with HRD was 23.8 and 17.1 months in patients without HRD. Without platinum-based chemotherapy, the average weighted median OS in patients with HRD was 8.3 and 12.0 months in patients without HRD. For resected PC, our meta-analysis demonstrated that HRD status did not affect the prognosis (HR 1.03, 95% CI 0.46 to 2.33), but results were rather heterogeneous (I2=83%, p=0.003). Our systematic analysis showed that the average weighted median OS in patients with HRD was 34.6 and 27.0 months in patients without HRD. With platinum-based chemotherapy, the average weighted median OS in patients with HRD was 46.1 and 36.3 months in patients without HRD. Without platinum-based chemotherapy, the average weighted median OS in patients with HRD was 24.2 and 42.9 months in patients without HRD. Results of our meta-analysis and systematic review support the idea of platinum use in patients with HRD both in resected and metastatic PCs, although a randomised trial is warranted to make a more reliable conclusion. PROSPERO REGISTRATION NUMBER: CRD42019121914.

Current and novel therapeutic opportunities for systemic therapy in biliary cancer

Biliary tract cancers (BTCs) are a group of rare and aggressive malignancies that arise in the biliary tree within and outside the liver. Beyond surgical resection, which is beneficial for only a small proportion of patients, current strategies for treating patients with BTCs include chemotherapy, as a single agent or combination regimens, in the adjuvant and palliative setting. Increased characterisation of the molecular landscape of these tumours has facilitated the identification of molecular vulnerabilities, such as IDH mutations and FGFR fusions, that can be exploited for the treatment of BTC patients. Beyond targeted therapies, active research avenues explore the development of novel therapeutics that target the crosstalk between cancer and stroma, the cellular pathways involved in the regulation of cell death, the chemoresistance phenotype and the dysregulation of RNA. In this review, we discuss the therapeutic opportunities currently available in the management of BTC patients, and explore the strategies that can support the implementation of precision oncology in BTCs, including novel molecular targets, liquid biopsies and patient-derived predictive tools.

Retrospective review of outcomes in patients with DNA-damage repair related pancreatic cancer

BACKGROUND

Patients with DNA-damage response genes (DDR)-related pancreas cancer (BRCA1/2 or other DNA-damage related genes) may have improved outcomes secondary to increased sensitivity to DNA-damaging drugs (platinum chemotherapy/ poly ADP ribose polymerase (PARP)-inhibitors). However, data is scarce pertaining to outcomes in this subset of patients. Our objective was to retrospectively identify DDR-related pancreas cancer patients and report on clinical outcomes.

METHODS

Pancreas cancer patients with a germline pathogenic variant in BRCA1/2 or other DDR gene were identified retrospectively through review of medical records (medical genetics/oncology) and genetic testing results at our institution. Data regarding clinical outcomes, therapy received, and survival was subsequently extracted.

RESULTS

A total of 11 patients with pancreas cancer were identified to carry a pathogenic DDR-variant: BRCA1 (3), ATM (4), BRCA2 (2), PALB2 (1) and FANCC (1). Five of these individuals had prior history of other cancers. Clinically these tumors were localized (4), locally advanced (3), and metastatic (4) at diagnosis. Four out of 11 patients were still alive at time of data review. Survival in the 7 patients who had died was 13.7, 140.0, 20.5, 22.3, 23.5, 25.8, and 111.5 months. All patients with advanced disease had exposure to platinum chemotherapy.

CONCLUSIONS

Historical survival in patients with advanced and metastatic pancreas cancer is poor. Results of this DDR-subset of patients do show significantly superior outcomes, likely secondary to exposure to platinum drugs. This data, alongside other similar cohorts, would favor the DDR-genes being a predictive marker with improved survival if exposed to these drugs and the new class of drugs, PARP-inhibitors.

A Phase I/II Study of Veliparib (ABT-888) in Combination with 5-Fluorouracil and Oxaliplatin in Patients with Metastatic Pancreatic Cancer

PURPOSE

Up to 17% of patients with pancreatic ductal adenocarcinoma (PDAC) harbor pathogenic (germline or somatic) mutations in a homologous recombination, DNA damage response and repair (HR-DDR) gene, such as BRCA1/2, or PALB2. Platinum-based chemotherapy, or treatment with PARP inhibitors are of particular benefit in these patients. However, there may be even greater benefit when platinums and PARP inhibitors are combined.

PATIENTS AND METHODS

We performed a single-arm, open-label, phase I/II study of the PARP inhibitor, veliparib, with 5-fluorouracil (no 5FU bolus) and oxaliplatin (FOLFOX) for patients with metastatic PDAC. Thirty-one patients were enrolled in a phase I dose escalation of veliparib (40 mg to 250 mg twice a day, days 1-7 of each 14-day cycle), to identify the recommended phase II dose (RP2D) of veliparib for the combination. Another 33 patients were enrolled in two parallel phase II trials to assess the objective response rate (ORR) in untreated or in previously treated patients. If available, germline or somatic testing was collected to identify pathogenic HR-DDR mutations.

RESULTS

The combination of veliparib and FOLFOX was tolerable at a RP2D of veliparib of 200 mg twice a day. The primary endpoint for both phase II cohorts was met, and the ORR overall was 26%. There was greater activity in platinum-naïve patients, and those who harbored a pathogenic HR-DDR mutation. Specifically, the ORR of HR-DDR mutated, platinum-naïve patients was 57%.

CONCLUSIONS

The combination of veliparib and FOLFOX was safe for patients with metastatic PDAC and showed promising activity particularly in patients with platinum-naïve disease that harbors a pathogenic HR-DDR mutation.

Association of Germline Variants in Human DNA Damage Repair Genes and Response to Adjuvant Chemotherapy in Resected Pancreatic Ductal Adenocarcinoma

BACKGROUND

The frequency and significance of the germline variants in DNA damage repair genes still need to be elucidated in patients with sporadic pancreatic ductal adenocarcinoma (PDAC). Our purpose was to determine whether germline variants in DNA damage repair genes were associated with survival of patients with sporadic PDAC.

STUDY DESIGN

We retrospectively identified 854 patients with sporadic PDAC with germline DNA sequenced in targeted 22 DNA damage repair genes by next-generation sequencing. Outcomes were compared in terms of clinicopathologic features, disease-free survival (DFS), and overall survival (OS).

RESULTS

Nineteen patients had deleterious mutations; 103 had variant(s) of unknown significance (VUS). Germline DNA damage repair deleterious variant carriers had superior DFS (median, 19.1 months vs 11.9 months, p = 0.012) and OS (median, 29.7 months vs 20.2 months, p = 0.034), as compared with wild-type patients. Germline DNA damage repair VUS variant carriers also had superior DFS when compared with wild-type patients. In subgroup analysis, this improved survival was limited to patients receiving adjuvant chemotherapy, deleterious variant carriers vs wild-type patients DFS (median 36.3 months vs 13.1 months, p = 0.006) and OS (median 43.7 months vs 24.3 months, p = 0.045), VUS variant carriers vs wild-type patients DFS (16.5 months vs 13.1 months, p = 0.007).

CONCLUSIONS

Having a deleterious variant in a DNA damage repair gene is associated with improved survival after resection and adjuvant chemotherapy for pancreatic ductal adenocarcinoma.

Alteration of Transforming Growth Factor β Signaling Pathway Predicts Worse Prognosis in Pancreatic Ductal Adenocarcinoma

OBJECTIVES

Transforming growth factor β (TGF-β) signaling pathway is one of the core pathways in pancreatic ductal adenocarcinoma (PDAC). Prognostic value of TGF-β pathway genes as a functionally related group in PDAC is rarely studied.

METHODS

Seventy-two PDAC patients who underwent surgery between November 30, 2015, and September 13, 2017, in West China Hospital, Sichuan University, were identified and included in this study. Whole-exome sequencing or targeted next-generation sequencing was performed with tumor tissue. Clinicopathologic characteristics and survival data were retrospectively collected and analyzed.

RESULTS

Genetic alterations were detected in 71 patients (98.6%). Although 1 patient (1.4%) had one genetic alteration, 33 patients (45.8%) had 2 to 4 alterations and 37 patients (51.4%) had 5 or more alterations. Twenty-five patients with TGF-β pathway alteration were identified as TGF-βm+ group. Other 47 patients were TGF-βm- group. Mutation of TGF-β pathway was independently associated with inferior survival (hazard ratio, 2.22, 95% confidence interval, 1.05-4.70, P = 0.04), especially in patients accepting radical surgery (hazard ratio, 3.25, 95% confidence interval, 1.01-10.49, P = 0.04).

CONCLUSIONS

Inferior prognosis was observed in PDACs with mutations of TGF-β pathway. Genomic information could help screen out patients at risk after surgery, and adjuvant therapy might benefit this subgroup of PDACs.

Neoadjuvant Therapy is Essential for Resectable Pancreatic Cancer

BACKGROUND

Awareness of the benefits of neoadjuvant therapy is increasing, but its use as an initial therapeutic option for patients with resectable pancreatic cancer remains controversial, especially for those patients without high-risk prognostic features. Even for patients with high-risk features who are candidates to receive neoadjuvant therapy, no standard regimen exists.

METHODS

In this review, we examined available data on the neoadjuvant therapy in patients with resectable pancreatic cancer, including prospective studies, retrospective studies, and ongoing clinical trials, by searching PubMed/MEDLINE, ClinicalTrials.gov, Web of Science, and Cochrane Library. The characteristics and results of screened studies were described.

RESULTS

Retrospective and prospective studies with reported results and ongoing randomized studies were included. For patients with resectable pancreatic cancer, neoadjuvant therapy provides benefits such as increased survival, decreased risk of comorbidities and mortality, and improved cost-effectiveness due to an increased completion rate of multimodal treatment. Highly active regimens such as FOLFIRINOX (folinic acid, fluorouracil, irinotecan, and oxaliplatin) or gemcitabine plus nab-paclitaxel are considered acceptable therapeutic regimens. Additionally, platinum-containing regimens other than FOLFIRINOX are acceptable for selected patients. Other therapies, such as chemoradiation treatment, immuno-oncology agents, and targeted therapies are being explored and the results are highly anticipated.

CONCLUSION

This review highlights the benefits of neoadjuvant therapy for resectable pancreatic cancer. Some regimens are currently acceptable, but need more evidence from well-designed clinical trials or should be used after being carefully examined by a multidisciplinary team.

Familial Pancreatic Cancer: Current Perspectives

Pancreatic cancer (PC) is a highly lethal disease, mostly incurable when detected. Thus, despite advances in PC treatments, only around 7% of patients survive 5-years after diagnosis. This morbid outcome is secondary to multifactorial reasons, such as late-stage diagnosis, rapid progression and minimal response to chemotherapy. Based on these factors, it is of special relevance to identify PC high-risk individuals in order to establish preventive and early detection measures. Although most PC are sporadic, approximately 10% cases have a familial basis. No main causative gene of PC has been identified but several known germline pathogenic mutations are related with an increased risk of this tumor. These inherited cancer syndromes represent 3% of all PC. On the other hand, in 7% of cases of PC, there is a strong family history without a causative germline mutation, a situation known as familial pancreatic cancer (FPC). In recent years, there is increasing evidence supporting the benefit of genetic germline analysis in PC patients, and periodic pancreatic screening in PC high-risk patients (mainly those with a lifetime risk greater than 5%), although there is no general agreement in the group of patients and individuals to study and screen. In the present review, we expose an update in the field of hereditary and FPC, with the aim of describing the current strategies and implications in genetic counseling, surveillance and therapeutic interventions.

Cancer stem cells as therapeutic targets of pancreatic cancer

The discovery of stem cells and their potential abilities in self-renewal and differentiation has opened a new horizon in medicine. Scientists have found a small population of stem cells in some types of cancers with the same functions as normal stem cells. There are two models for tumor progression: clonal (stochastic) and cancer stem cell (CSCs) models. According to the first model, all transformed cells in the tumor have carcinogenic potential and are able to proliferate and produce the same cells. The latter model, which has received more attention recently, considers the role of CSCs in drug resistance and tumor metastasis. Following the model, researchers have found that targeting CSCs may be a promising way in cancer therapy. This review describes CSC characteristics in general, while also focusing on CSC properties in the context of pancreatic cancer.

Retrospective Survival Analysis of Patients With Resected Pancreatic Ductal Adenocarcinoma and a Germline BRCA or PALB2 Mutation

PURPOSE

Germline mutations in the homologous recombination genes BRCA1, BRCA2, and PALB2 confer an increased risk for pancreatic ductal adenocarcinoma (PDAC). Tumors associated with mutations in homologous recombination genes are sensitive to DNA-damaging agents. We retrospectively studied patients with resected PDAC and a pathogenic germline mutation in one of these three genes. The planned analyses included overall survival (OS) and changes therein when platinum chemotherapy was used in the perioperative setting.

MATERIALS AND METHODS

Thirty-two individuals with pathogenic germline mutations in BRCA1, BRCA2, or PALB2 and resected PDAC (mutation positive) were matched in a 1:2 fashion to patients who were noncarriers or untested (mutation negative) by age, year of diagnosis, stage, and sex. Patients were identified via one of two available databases at University of Pennsylvania: the Basser Center for BRCA Registry or the electronic medical record. The primary outcome was OS.

RESULTS

Patients in the mutation-positive group had a median OS (mOS) of 46.6 months; those in the mutation-negative group had an mOS of 23.2 months (hazard ratio [HR], 0.49; 95% CI, 0.27 to 0.88). With platinum exposure in the perioperative setting, mOS in the mutation-positive group had not yet been met versus a mOS of 23.1 months in the mutation-negative group (HR, 0.12; 95% CI, 0.01 to 1.00). When neither group was treated with platinum, there was no significant OS difference between groups (HR, 0.52; 95% CI 0.12 to 2.24). Patients in the mutation-positive group who received perioperative treatment with platinum had a trend toward improved mOS compared with those who did not (HR, 0.15; 95% CI, 0.02 to 1.23; P = .07).

CONCLUSION

Platinum-based chemotherapy may confer a survival benefit in patients with resected PDAC and a pathogenic germline BRCA1, BRCA2, or PALB2 mutation. Knowledge of a germline mutation may be important to determine best choice of perioperative chemotherapy.

DNA damage repair deficiency as a predictive biomarker for FOLFIRINOX efficacy in metastatic pancreatic cancer

Patients with pathogenic germline and somatic variants in DNA damage repair (DDR) genes may derive greater benefit with platinum-based chemotherapy in metastatic pancreatic ductal adenocarcinoma (PDAC). This study investigates the role of DDR genes as a predictive biomarker for response to first-line platinum chemotherapy with FOLFIRINOX in metastatic PDAC patients. Demographic, clinical, and pathologic variables were collected for patients with metastatic PDAC who received FOLFIRINOX as frontline treatment and who had germline and somatic genetic testing. Kaplan-Meier analysis of overall survival (OS) and progression free survival (PFS) were correlated to the presence of DDR pathogenic variants. Forty patients with metastatic PDAC met inclusion criteria. Germline genetic testing revealed germline pathogenic variants in DDR genes in 5 patients (12%), and somatic pathogenic variants in DDR genes in 4 patients (10%). Median PFS was significantly longer in patients with any (germline or somatic) pathogenic variant in DDR genes than in those without alterations 18.5 vs. 6.9 months (log-rank P=0.003). When restricted to the presence or absence of germline pathogenic variants in DDR genes, the median PFS was 18.5 vs. 7.4 months (log-rank P=0.005). The median OS for the entire cohort was 11.5 months was not statistically different between the two groups, however there were no deaths in the subgroup with germline pathogenic variants in DDR genes treated with frontline FOLFIRINOX. A subset of patients with metastatic PDAC and germline or somatic pathogenic variants in DDR genes have a statistically superior PFS when treated with the platinum containing regimen FOLFIRINOX. The role of DDR gene alterations as a predictive biomarker for FOLFIRINOX benefit should be further evaluated in prospective trials.

Outcomes in Patients With Pancreatic Adenocarcinoma With Genetic Mutations in DNA Damage Response Pathways: Results From the Know Your Tumor Program

PURPOSE

Up to 25% of pancreatic adenocarcinomas (PDACs) harbor mutations in the homologous recombination DNA damage response (HR-DDR) pathway. Although known to affect responsiveness to DNA-damaging chemotherapy, the prognostic relevance of these mutations is unclear and outcomes in patients with PDAC who harbor HR-DDR mutations beyond BRCA1/2 remain unexplored.

METHODS

We evaluated 820 patients with PDAC enrolled in the Know Your Tumor program for whom we had collected comprehensive genomic testing results and longitudinal clinical outcomes. Patients were categorized as having resected versus advanced disease, and as having received platinum-based therapy versus being platinum naïve. Tumor genomic profiles were categorized as HR-DDR mutated (HR-DDRmut) or proficient (pHR-DDR) on the basis of the presence of pathogenic mutations of somatic or germline origin in BRCA1/2 or PALB2 (group 1); ATM/ATR/ATRX (group 2); or BAP1, BARD1, BRIP1, CHEK1/2, RAD50/51/51B, or FANCA/C/D2/E/F/G/L (group 3). Overall survival was measured from the date of diagnosis until death.

RESULTS

Median overall survival (mOS) was similar in all resected patients irrespective of exposure to platinum-based therapy, whereas for platinum-treated patients with advanced disease, mOS was significantly longer for HR-DDRmut versus pHR-DDR (2.37 years v 1.45 years, respectively). Of importance, no difference was identified in platinum-naïve patients. mOS in patients with mutations in all three HR-DDRmut groups was greater than that for pHR-DDR patients, but this difference was lost in platinum-naïve patients.

CONCLUSION

Patients with advanced HR-DDRmut have improved mOS when treated with platinum-based therapy compared with pHR-DDR patients. In platinum-naïve patients, there is no mOS difference, which suggests that HR-DDR status has no pure prognostic value. These findings support the need to test all patients with advanced PDAC to ensure that HR-DDRmut patients receive the benefit of treatment with platinum-based therapy.

Should platinum-based chemotherapy be preferred for germline BReast CAncer genes (BRCA) 1 and 2-mutated pancreatic ductal adenocarcinoma (PDAC) patients? A systematic review and meta-analysis

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal cancers worldwide. Recent studies have shown that 4-20% of patients with PDAC have a germline BReast CAncer (gBRCA) genes 1 and 2 mutation (m). Because homologous recombination is impaired in patients with gBRCAm, some reports suggested that these tumors may be more sensitive to platinum compounds. Therefore, this systematic review and meta-analysis focused on benefit of patients with gBRCAm receiving a platinum-based chemotherapy (PtCh) compared with those treated with a non-platinum-based chemotherapy (NPtCh).

MATERIAL AND METHODS

The following electronic databases were searched from inception to May 12, 2018: PubMed (MEDLINE), EMBASE, and Cochrane Library. Abstracts from conferences were also reviewed for inclusion. Cohort, case-control and randomized studies of patients with PDAC and gBRCAm were eligible for inclusion if they provided data to compare patients receiving PtCh vs NPtCh. The primary endpoint was overall survival (OS) in the PtCh group vs the NPtCh group in patients with clinical stage III (locally advanced) or IV (metastatic) (CS III-IV) PDAC.

RESULTS

Of 112 studies identified, 6 were included (total of 108 patients); of these, 4 provided sufficient data for meta-analysis. Half of the patients were males, with a mean age ranging from 58 to 63 years. The OS in the 85 patients with CS III-IV PDAC was higher in the PtCh group (23.7 vs 12.2 months; mean difference of 10.21 months, 95% confidence interval [CI] 5.05-15.37; P < 0.001; very low quality of evidence). PtCh was associated with a lower mortality (62.3 vs 87.5%; relative risk of 0.80, 95%CI 0.66-0.97; P = 0.021; very low quality of evidence).

CONCLUSION

Our study confirmed the hypothesis that patients with CS III-IV gBRCAm preferably benefit from a PtCh compared with NPtCh. However the very low quality of evidence should induce to be careful about the risk of potential biases. The generated hypothesis should be prospectively investigated in homogenous clinical settings.

Impact of BRCA1/2 gene mutations on survival of patients with pancreatic cancer: A case-series analysis

BRCA gene mutations are found in up to 10% of pancreatic adenocarcinoma cases. We present a description of 4 cases along with a review of the current literature regarding pathogenesis, target treatment, response and survival rates in these types of malignancies. We describe four cases of pancreatic adenocarcinoma, in three of which the BRCA2 mutation was identified, in one - BRCA1 gene alteration. Two patients underwent surgery following the neoadjuvant treatment with Folfirinox and radiotherapy; in the first case, a distal pancreatectomy with splenectomy was performed and in the second one - the Whipple's procedure. In both cases, a complete pathological response was reported. Other 2 patients were treated with Folfirinox after BRCA mutation identification and acceptable life expectancy was obtained. The association of pathologic complete response (PCR) with lower rates of local recurrence and better survival in patients with various types of adenocarcinomas is well known. Identification of such patients carrying BRCA mutations could provide an application of better personalized treatment. In some patients with pancreatic cancer, especially when there is clinical or demographic reason to suspect a genetic predisposition, a confirmation of the presence of BRCA mutations could provide an opportunity to use target treatment with beneficial outcomes regarding survival.

Genetics of Familial and Sporadic Pancreatic Cancer

In the previous decade, comprehensive genomic analyses have yielded important insights about the genetic alterations that underlie pancreatic tumorigenesis. Whole-exome and whole-genome sequencing of pancreatic ductal adenocarcinomas have confirmed the critical driver genes altered in the majority of pancreatic cancers, as well as identified numerous less frequently altered driver genes, and have delineated cancer subgroups with unique biological and clinical features. It is now appreciated that pancreatic susceptibility gene alterations are often identified in patients with pancreatic cancer without family histories suggestive of a familial cancer syndrome, prompting recent efforts to expand gene testing to all patients with pancreatic cancer. Studies of pancreatic cancer precursor lesions have begun to elucidate the evolutionary history of pancreatic tumorigenesis and to help us understand the utility of biomarkers for early detection and targets to develop new therapeutic strategies. In this review, we discuss the results of comprehensive genomic characterization of pancreatic ductal adenocarcinoma and its precursor lesions, and we highlight translational applications in early detection and therapy.

Genomic profiling in pancreatic ductal adenocarcinoma and a pathway towards therapy individualization: A scoping review

CONTEXT

Pancreatic cancer (PDAC) is one of the most challenging cancers to treat with modest recent improvements in survival from new systemic therapies. There is growing interest in individualized therapy underpinned by somatic and germline genomic alterations.

OBJECTIVE

A systematic review of data on therapies targeting somatic and germline alterations, and their downstream pathways in PDAC.

METHOD

A systematic literature search was conducted using PRISMA guidelines to include relevant results published after January 1, 2008.

RESULTS

A total of 71 relevant studies were included. We identified 36 studies targeting the KRAS-pathway, the most common being with MEK-inhibitor therapy. Twenty-two studies were identified that evaluated platinum-based chemotherapy and PARP inhibitors in patients with deleterious mutations in DNA damage repair genes and have shown encouraging results. Immunotherapy has demonstrated activity in patients with mismatch repair deficiency/microsatellite instability.

CONCLUSION

Evidence from translational and clinical research presents an exciting platform for genomic targeted therapy in PDAC. Validity for targeting BRCA with platinum and PARP inhibitors and microsatellite instability with immune therapy has been established, nonetheless, evidence for targeting the common driver oncogenes is lacking and much work is needed. Of importance is identifying the subgroup of KRAS -wild type PDAC (approximately 5%) where there is enrichment for targetable opportunities.

Germline cancer susceptibility gene variants, somatic second hits, and survival outcomes in patients with resected pancreatic cancer

PURPOSE

Germline variants in double-strand DNA damage repair (dsDDR) genes (e.g., BRCA1/2) predispose to pancreatic adenocarcinoma (PDAC) and may predict sensitivity to platinum-based chemotherapy and poly(ADP) ribose polymerase (PARP) inhibitors. We sought to determine the prevalence and significance of germline cancer susceptibility gene variants in PDAC with paired somatic and survival analyses.

METHODS

Using a customized next-generation sequencing panel, germline/somatic DNA was analyzed from 289 patients with resected PDAC ascertained without preselection for high-risk features (e.g., young age, personal/family history). All identified variants were assessed for pathogenicity. Outcomes were analyzed using multivariable-adjusted Cox proportional hazards regression.

RESULTS

We found that 28/289 (9.7%; 95% confidence interval [CI] 6.5-13.7%) patients carried pathogenic/likely pathogenic germline variants, including 21 (7.3%) dsDDR gene variants (3 BRCA1, 4 BRCA2, 14 other dsDDR genes [ATM, BRIP1, CHEK2, NBN, PALB2, RAD50, RAD51C]), 3 Lynch syndrome, and 4 other genes (APC p.I1307K, CDKN2A, TP53). Somatic sequencing and immunohistochemistry identified second hits in the tumor in 12/27 (44.4%) patients with germline variants (1 failed sequencing). Compared with noncarriers, patients with germline dsDDR gene variants had superior overall survival (hazard ratio [HR] 0.54; 95% CI 0.30-0.99; P = 0.05).

CONCLUSION

Nearly 10% of PDAC patients harbor germline variants, although the majority lack somatic second hits, the therapeutic significance of which warrants further study.

Emerging strategies in BRCA-positive pancreatic cancer

PURPOSE

We propose a treatment algorithm for PDAC with particular emphasis on BRCA1 or 2 mutation-positive patients. Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest diseases in the United States and Europe. BRCA1 and BRCA2 are among the most common of the known genetic mutations involved in familial PDAC. The optimal chemotherapy regimen to use for BRCA1 or 2 mutation carriers with PDAC is not yet established. As new treatment options emerge, algorithms must balance the need to give the best drugs first with ensuring that there are still beneficial options available for later.

METHODS

We conducted a review of the literature for data on possible therapies in BRCA-positive and BRCA-negative pancreatic cancer.

RESULTS

There is accumulating evidence of increased sensitivity to platinum-based therapy and poly-ADP-ribose polymerase inhibitors (PARPi) in BRCA-associated PDAC. There are no studies relating to borderline BRCA-associated PDAC and, therefore, same treatment as for sporadic PDAC seems appropriate. Treatment of unresectable PDAC varies depending on stage of the disease. Patients with BRCA-associated locally advanced PDAC can benefit from targeted therapy with PARPi (olaparib) as a second-line therapy after antimetabolite treatment failure. Patients with unresectable metastatic BRCA-positive PDAC may benefit from platinum-based therapy.

CONCLUSION

Targeted therapies are shifting the treatment paradigms and increasing survival for patients with PDAC, a group that used to have a grim prognosis.