Immunotherapy and Pancreatic Cancer: A Lost Challenge?

Although immunotherapy has proved to be a very efficient therapeutic strategy for many types of tumors, the results for pancreatic cancer (PC) have been very poor. Indeed, chemotherapy remains the standard treatment for this tumor in the advanced stage. Clinical data showed that only a small portion of PC patients with high microsatellite instability/mismatch repair deficiency benefit from immunotherapy. However, the low prevalence of these alterations was not sufficient to lead to a practice change in the treatment strategy of this tumor. The main reasons for the poor efficacy of immunotherapy probably lie in the peculiar features of the pancreatic tumor microenvironment in comparison with other malignancies. In addition, the biomarkers usually evaluated to define immunotherapy efficacy in other cancers appear to be useless in PC. This review aims to describe the main features of the pancreatic tumor microenvironment from an immunological point of view and to summarize the current data on immunotherapy efficacy and immune biomarkers in PC.

Immunotherapy in Prostate Cancer: State of Art and New Therapeutic Perspectives

Prostate cancer (PC) is the most common type of tumor in men. In the early stage of the disease, it is sensitive to androgen deprivation therapy. In patients with metastatic castration-sensitive prostate cancer (mHSPC), chemotherapy and second-generation androgen receptor therapy have led to increased survival. However, despite advances in the management of mHSPC, castration resistance is unavoidable and many patients develop metastatic castration-resistant disease (mCRPC). In the past few decades, immunotherapy has dramatically changed the oncology landscape and has increased the survival rate of many types of cancer. However, immunotherapy in prostate cancer has not yet given the revolutionary results it has in other types of tumors. Research into new treatments is very important for patients with mCRPC because of its poor prognosis. In this review, we focus on the reasons for the apparent intrinsic resistance of prostate cancer to immunotherapy, the possibilities for overcoming this resistance, and the clinical evidence and new therapeutic perspectives regarding immunotherapy in prostate cancer with a look toward the future.

The Resistance to EGFR-TKIs in Non-Small Cell Lung Cancer: From Molecular Mechanisms to Clinical Application of New Therapeutic Strategies

Almost 17% of Western patients affected by non-small cell lung cancer (NSCLC) have an activating epidermal growth factor receptor (EGFR) gene mutation. Del19 and L858R are the most-common ones; they are positive predictive factors for EGFR tyrosine kinase inhibitors (TKIs). Currently, osimertinib, a third-generation TKI, is the standard first-line therapy for advanced NSCLC patients with common EGFR mutations. This drug is also administered as a second-line treatment for those patients with the T790M EGFR mutation and previously treated with first- (erlotinib, gefitinib) or second- (afatinib) generation TKIs. However, despite the high clinical efficacy, the prognosis remains severe due to intrinsic or acquired resistance to EGRF-TKIs. Various mechanisms of resistance have been reported including the activation of other signalling pathways, the development of secondary mutations, the alteration of the downstream pathways, and phenotypic transformation. However, further data are needed to achieve the goal of overcoming resistance to EGFR-TKIs, hence the necessity of discovering novel genetic targets and developing new-generation drugs. This review aimed to deepen the knowledge of intrinsic and acquired molecular mechanisms of resistance to EGFR-TKIs and the development of new therapeutic strategies to overcome TKIs' resistance.

Advances in pharmacotherapies that target the cell cycle for treatment of breast cancer: where are we at today?

INTRODUCTION

Advances in pharmacotherapies that target cell cycle in breast cancer have transformed the therapeutic armamentarium of breast oncology leading to the approval of CDK4/6 inhibitors plus endocrine therapy as the upfront treatment in the HR+/HER2- metastatic setting. The current challenge is to evaluate the efficacy of these drugs in the early setting. The current challenge is to evaluate the efficacy of these drugs in the early setting. Research is also making progress for other breast cancer subtypes (triple negative and HER 2+ breast cancer).

AREAS COVERED

The aim of this review is to summarize the recent therapeutic updates regarding the efficacy of CDK4/6 inhibitors in the metastatic and early setting for the treatment of HR+/HER2- breast cancer. The review also presents data regarding the clinical role of CDK4/6 inhibitors in HER2+, triple negative breast cancer and on therapeutic sequences in resistant tumors. A comprehensive search for the literature was conducted using MEDLINE, ASCO, ESMO and SABCS databases.

EXPERT OPINION

The therapeutic paradigm of breast cancer involving CDK4/6 inhibitors presents some still open discussion points. Further evidence regarding the best treatment strategy in HR+ HER2- metastatic breast cancer and the efficacy of CDK 4/6is in the early stage will be necessary in the next future. Predictive biomarkers of response or resistance need to be validated.

Carboplatin and paclitaxel plus avelumab compared with carboplatin and paclitaxel in advanced or recurrent endometrial cancer (MITO END-3): a multicentre, open-label, randomised, controlled, phase 2 trial

BACKGROUND

Adding immunotherapy to first-line chemotherapy might improve outcomes for patients with advanced or recurrent endometrial cancer. We aimed to compare carboplatin and paclitaxel versus avelumab plus carboplatin and paclitaxel as first-line treatment with avelumab given concurrent to chemotherapy and as maintenance after the end of chemotherapy.

METHODS

MITO END-3 is an open-label, randomised, controlled, phase 2 trial conducted at 31 cancer institutes, hospitals, and universities in Italy. Eligible patients were aged 18 years or older with histologically confirmed advanced (FIGO stage III-IV) or recurrent endometrial cancer, an Eastern Cooperative Oncology Group (ECOG) performance status of 0-1, and no previous systemic anticancer therapy as primary treatment for advanced or metastatic disease. Participants were randomly assigned (1:1) using a computerised minimisation procedure stratified by centre, histology, and stage at study entry, to either receive carboplatin (area under the curve [AUC] 5 mg/mL × min) and paclitaxel (175 mg/m²; standard group) intravenously every 3 weeks for six to eight cycles or avelumab (10 mg/kg intravenously) added to carboplatin and paclitaxel (experimental group) every 3 weeks and then every 2 weeks as a single maintenance treatment after the end of chemotherapy until disease progression or unacceptable toxicity. Patients, treating clinicians, and those assessing radiological examinations were not masked to study treatment. The primary endpoint was investigator-assessed progression-free survival, measured in the intention-to-treat (ITT) population. Patients who received at least one dose of study drug were included in the safety analysis. Experimental group superiority was tested with 80% power and one-tailed α 0·20. This trial is registered with ClinicalTrials.gov (NCT03503786) and EudraCT (2016-004403-31).

FINDINGS

From April 9, 2018, to May 13, 2021, 166 women were assessed for eligibility and 39 were excluded. 125 eligible patients were randomly assigned to receive carboplatin and paclitaxel (n=62) or avelumab plus carboplatin and paclitaxel (n=63) and included in the ITT population. The median follow-up was 23·3 months (IQR 13·2-29·6) and was similar between the two groups. 91 progression-free survival events were reported, with 49 events in 62 patients in the standard group and 42 events in 63 patients in the experimental group. The median progression-free survival was 9·9 months (95% CI 6·7-12·1) in the standard group and 9·6 months (7·2-17·7) in the experimental group (HR of progression or death 0·78 [60% CI 0·65-0·93]; one-tailed p=0·085). Serious adverse events were reported more frequently in the experimental group (24 vs seven events in the standard group); neutrophil count decrease was the most frequent grade 3-4 adverse event (19 [31%] of 61 patients in the experimental group vs 26 [43%] of 61 patients in the standard group). Two deaths occurred in the experimental group during treatment (one respiratory failure following severe myositis [possibly related to treatment] and one cardiac arrest [not related to treatment]).

INTERPRETATION

Adding avelumab to first-line chemotherapy deserves further testing in patients with advanced or recurrent endometrial cancer, although consideration of mismatch repair status is warranted.

FUNDING

Pfizer.

Beyond BRCA: The Emerging Significance of DNA Damage Response and Personalized Treatment in Pancreatic and Prostate Cancer Patients

The BRCA1/2 germline and/or somatic pathogenic variants (PVs) are key players in the hereditary predisposition and therapeutic response for breast, ovarian and, more recently, pancreatic and prostate cancers. Aberrations in other genes involved in homologous recombination and DNA damage response (DDR) pathways are being investigated as promising targets in ongoing clinical trials. However, DDR genes are not routinely tested worldwide. Due to heterogeneity in cohort selection and dissimilar sequencing approaches across studies, neither the burden of PVs in DDR genes nor the prevalence of PVs in genes in common among pancreatic and prostate cancer can be easily quantified. We aim to contextualize these genes, altered in both pancreatic and prostate cancers, in the DDR process, to summarize their hereditary and somatic burden in different studies and harness their deficiency for cancer treatments in the context of currently ongoing clinical trials. We conclude that the inclusion of DDR genes, other than BRCA1/2, shared by both cancers considerably increases the detection rate of potentially actionable variants, which are triplicated in pancreatic and almost doubled in prostate cancer. Thus, DDR alterations are suitable targets for drug development and to improve the outcome in both pancreatic and prostate cancer patients. Importantly, this will increase the detection of germline pathogenic variants, thereby patient referral to genetic counseling.

An update on our ability to monitor castration-resistant prostate cancer dynamics with cell-free DNA

Introduction: Prostate cancer is one of the most frequent tumors worldwide. Due to the lack of reliable markers, patients are usually diagnosed at a late stage when it becomes castration-resistant prostate cancer (CRPC) with a worse outcome. Thus, it is essential to ameliorate the clinical management of these patients. Nowadays, the use of liquid biopsy represents a minimally invasive way to provide a complete molecular landscape of prostate cancer. Thus, this review aims to outline the clinical value of cell-free DNA in real-time monitoring of metastatic CRPC (mCRPC).Areas covered: This comprehensive review explores in detail the characteristics as well as clinical applications of plasma DNA analysis in mCRPC.Expert opinion: The assessment of circulating tumor DNA fraction is a valid and robust biomarker in mCRPC able to predict clinical outcome and monitor disease evolution during treatment. Recently, several methods (i.e. next generation sequencing and digital droplet PCR) are used to investigate genomics in cell-free DNA and novel nanotechnology-based approaches are currently under evaluation in order to improve clinical management of mCRPC patients.

Immunotherapy and Its Development for Gynecological (Ovarian, Endometrial and Cervical) Tumors: From Immune Checkpoint Inhibitors to Chimeric Antigen Receptor (CAR)-T Cell Therapy

Gynecological tumors are malignancies with both high morbidity and mortality. To date, only a few chemotherapeutic agents have shown efficacy against these cancer types (only ovarian cancer responds to several agents, especially platinum-based combinations). Within this context, the discovery of immune checkpoint inhibitors has led to numerous clinical studies being carried out that have also demonstrated their activity in these cancer types. More recently, following the development of chimeric antigen receptor (CAR)-T cell therapy in hematological malignancies, this strategy was also tested in solid tumors, including gynecological cancers. In this article, we focus on the molecular basis of gynecological tumors that makes them potential candidates for immunotherapy. We also provide an overview of the main immunotherapy studies divided by tumor type and report on CAR technology and the studies currently underway in the area of gynecological malignancies.

Abscopal effect after hypofractionated radiotherapy in metastatic renal cell carcinoma pretreated with pazopanib

Background: The abscopal effect consists of distant metastases response after local treatment based on systemic immune stimulation. It is a rare event observed in many tumors, especially with radiotherapy and immunotherapy. Clinical case: We report the long-term abscopal effect in a metastatic renal cell carcinoma patient with lung metastasectomy, after hypofractionated radiotherapy on lymph node metastasis. The patient was pretreated with pazopanib, which was discontinued early owing to toxicity before radiotherapy. Methodology: Immunohistological analyses of the primary tumor and metastases were performed. Discussion: We supposed that radiotherapy, and maybe tyrosine kinase inhibitors, could act as immune-primers for abscopal effect modifying the immune tumor microenvironment. Conclusion: Future studies are needed to optimize the combination of radiotherapy with systemic therapy for better long-term tumor control in selected patients.

Overcoming resistance to anti-PD1 and anti-PD-L1 treatment in gastrointestinal malignancies

In the last few years, the unprecedented results of immune checkpoint inhibitors have led to a paradigm shift in clinical practice for the treatment of several cancer types. However, the vast majority of patients with gastrointestinal cancer do not benefit from immunotherapy. To date, microsatellite instability high and DNA mismatch repair deficiency are the only robust predictive biomarkers of response to immune checkpoint inhibitors. Unfortunately, these patients comprise only 5%-10% of all gastrointestinal cancers. Several mechanisms of both innate and adaptive resistance to immunotherapy have been recognized that may be at least in part responsible for the failure of immune checkpoint inhibitors in this population of patients. In the first part of this review article, we provide an overview of the main clinical trials with immune checkpoint inhibitors in patients with gastrointestinal cancer and the role of predictive biomarkers. In the second part, we discuss the actual body of knowledge in terms of mechanisms of resistance to immunotherapy and the most promising approach that are currently under investigation in order to expand the population of patients with gastrointestinal cancer who could benefit from immune checkpoint inhibitors.