Showing papers in "Nature Reviews Clinical Oncology in 2013"

Liquid biopsy: monitoring cancer-genetics in the blood.

Abstract: Cancer is associated with mutated genes, and analysis of tumour-linked genetic alterations is increasingly used for diagnostic, prognostic and treatment purposes. The genetic profile of solid tumours is currently obtained from surgical or biopsy specimens; however, the latter procedure cannot always be performed routinely owing to its invasive nature. Information acquired from a single biopsy provides a spatially and temporally limited snap-shot of a tumour and might fail to reflect its heterogeneity. Tumour cells release circulating free DNA (cfDNA) into the blood, but the majority of circulating DNA is often not of cancerous origin, and detection of cancer-associated alleles in the blood has long been impossible to achieve. Technological advances have overcome these restrictions, making it possible to identify both genetic and epigenetic aberrations. A liquid biopsy, or blood sample, can provide the genetic landscape of all cancerous lesions (primary and metastases) as well as offering the opportunity to systematically track genomic evolution. This Review will explore how tumour-associated mutations detectable in the blood can be used in the clinic after diagnosis, including the assessment of prognosis, early detection of disease recurrence, and as surrogates for traditional biopsies with the purpose of predicting response to treatments and the development of acquired resistance.

Image-guided cancer surgery using near-infrared fluorescence.

Abstract: Optical imaging that exploits invisible near-infrared (NIR) fluorescent light (700–900 nm) has the potential to improve cancer surgery outcomes, minimize anaesthesia time and lower health-care costs via its improved contrast and depth of tissue penetration relative to visible light. This Review introduces the concept of NIR fluorescence imaging and examines imaging system and contrast agent optimization. Paradigm shifts in surgery arise when surgeons are empowered to perform surgery faster, better and less expensively than current standards. Optical imaging that exploits invisible near-infrared (NIR) fluorescent light (700–900 nm) has the potential to improve cancer surgery outcomes, minimize the time patients are under anaesthesia and lower health-care costs largely by way of its improved contrast and depth of tissue penetration relative to visible light. Accordingly, the past few years have witnessed an explosion of proof-of-concept clinical trials in the field. In this Review, we introduce the concept of NIR fluorescence imaging for cancer surgery, examine the clinical trial literature to date and outline the key issues pertaining to imaging system and contrast agent optimization. Although NIR seems to be superior to many traditional imaging techniques, its incorporation into routine care of patients with cancer depends on rigorous clinical trials and validation studies.

Understanding the mechanisms and treatment options in cancer cachexia

Abstract: Cancer cachexia is a metabolic syndrome that can be present even in the absence of weight loss ('precachexia'). Cachexia is often compounded by pre-existing muscle loss, and is exacerbated by cancer therapy. Furthermore, cachexia is frequently obscured by obesity, leading to under-diagnosis and excess mortality. Muscle wasting (the signal event in cachexia) is associated not only with reduced quality of life, but also markedly increased toxicity from chemotherapy. Many of the primary events driving cachexia are likely mediated via the central nervous system and include inflammation-related anorexia and hypoanabolism or hypercatabolism. Treatment of cachexia should be initiated early. In addition to active management of secondary causes of anorexia (such as pain and nausea), therapy should target reduced food intake (nutritional support), inflammation-related metabolic change (anti-inflammatory drugs or nutrients) and reduced physical activity (resistance exercise). Advances in the understanding of the molecular biology of the brain, immune system and skeletal muscle have provided novel targets for the treatment of cachexia. The combination of therapies into a standard multimodal package coupled with the development of novel therapeutics promises a new era in supportive oncology whereby quality of life and tolerance to cancer therapy could be improved considerably.

Development of PI3K inhibitors: lessons learned from early clinical trials

Abstract: The phosphatidylinositol 3-kinase (PI3K) pathway has an important role in cell metabolism, growth, migration, survival and angiogenesis. Drug development aimed at targetable genetic aberrations in the PI3K/AKT/mTOR pathway has been fomented by observations that alterations in this pathway induce tumour formation and that inappropriate PI3K signalling is a frequent occurrence in human cancer. Many of the agents developed have been evaluated in early stage clinical trials. This Review focuses on early clinical and translational data related to inhibitors of the PI3K/AKT/mTOR pathway, as these data will likely guide the further clinical development of such agents. We review data from those trials, delineating the safety profile of the agents--whether observed sequelae could be mechanism-based or off-target effects--and drug efficacy. We describe predictive biomarkers explored in clinical trials and preclinical mechanisms of resistance. We also discuss key unresolved translational questions related to the clinical development of inhibitors of the PI3K/AKT/mTOR pathway and propose designs for biomarker-driven trials to address those issues.

Latest research and treatment of advanced-stage epithelial ovarian cancer

Abstract: The natural history of ovarian cancer continues to be characterized by late-stage presentation, metastatic bulky disease burden and stagnant mortality statistics, despite prolific drug development. Robust clinical investigation, particularly with modifications to primary treatment surgical goals and adjuvant therapy are increasing median progression-free survival and overall survival, although the cure rates have been affected only modestly. Maintenance therapy holds promise, but studies have yet to identify an agent and/or strategy that can affect survival. Recurrent disease is largely an incurable state; however, current intervention with selected surgery, combination and targeted therapy and investigational protocols are impacting progression-free survival. Ovarian cancer is a diverse and genomically complex disease, which commands global attention. Rational investigation must balance the high rate of discovery with lagging clinical investigation and limited patient resources. Nevertheless, growth in our armamentarium offers unprecedented opportunities for patients suffering with this disease. This Review presents and reviews the contemporary management of the disease spectrum termed epithelial 'ovarian' cancer and describes the direction and early results of clinical investigation.

Treating B-cell cancer with T cells expressing anti-CD19 chimeric antigen receptors

Abstract: Most B-cell malignancies express CD19, and a majority of patients with B-cell malignancies are not cured by current standard therapies. Chimeric antigen receptors (CARs) are fusion proteins consisting of antigen recognition moieties and T-cell activation domains. T cells can be genetically modified to express CARs, and adoptive transfer of anti-CD19 CAR T cells is now being tested in clinical trials. Effective clinical treatment with anti-CD19 CAR T cells was first reported in 2010 after a patient with advanced-stage lymphoma treated at the NCI experienced a partial remission of lymphoma and long-term eradication of normal B cells. Additional patients have subsequently obtained long-term remissions of advanced-stage B-cell malignancies after infusions of anti-CD19 CAR T cells. Long-term eradication of normal CD19(+) B cells from patients receiving infusions of anti-CD19 CAR T cells demonstrates the potent antigen-specific activity of these T cells. Some patients treated with anti-CD19 CAR T cells have experienced acute adverse effects, which were associated with increased levels of serum inflammatory cytokines. Although anti-CD19 CAR T cells are at an early stage of development, the potent antigen-specific activity observed in patients suggests that infusions of anti-CD19 CAR T cells might become a standard therapy for some B-cell malignancies.

Charged particle therapy--optimization, challenges and future directions.

Abstract: The use of charged particle therapy to control tumours non-invasively offers advantages over conventional radiotherapy. Protons and heavy ions deposit energy far more selectively than X-rays, allowing a higher local control of the tumour, a lower probability of damage to healthy tissue, low risk of complications and the chance for a rapid recovery after therapy. Charged particles are also useful for treating tumours located in areas that surround tissues that are radiosensitive and in anatomical sites where surgical access is limited. Current trial outcomes indicate that accelerated ions can potentially replace surgery for radical cancer treatments, which might be beneficial as the success of surgical cancer treatments are largely dependent on the expertise and experience of the surgeon and the location of the tumour. However, to date, only a small number of controlled randomized clinical trials have made comparisons between particle therapy and X-rays. Therefore, although the potential advantages are clear and supported by data, the cost:benefit ratio remains controversial. Research in medical physics and radiobiology is focusing on reducing the costs and increasing the benefits of this treatment.

Gastric cancer—molecular and clinical dimensions

Abstract: Gastric cancer imposes a considerable health burden around the globe despite its declining incidence. The disease is often diagnosed in advanced stages and is associated with a poor prognosis for patients. An in-depth understanding of the molecular underpinnings of gastric cancer has lagged behind many other cancers of similar incidence and morbidity, owing to our limited knowledge of germline susceptibility traits for risk and somatic drivers of progression (to identify novel therapeutic targets). A few germline (PLCE1) and somatic (ERBB2, ERBB3, PTEN, PI3K/AKT/mTOR, FGF, TP53, CDH1 and MET) alterations are emerging and some are being pursued clinically. Novel somatic gene targets (ARID1A, FAT4, MLL and KMT2C) have also been identified and are of interest. Variations in the therapeutic approaches dependent on geographical region are evident for localized gastric cancer-differences that are driven by preferences for the adjuvant strategies and the extent of surgery coupled with philosophical divides. However, greater uniformity in approach has been noted in the metastatic cancer setting, an incurable condition. Having realized only modest successes, momentum is building for carrying out more phase III comparative trials, with some using biomarker-based patient selection strategies. Overall, rapid progress in biotechnology is improving our molecular understanding and can help with new drug discovery. The future prospects are excellent for defining biomarker-based subsets of patients and application of specific therapeutics. However, many challenges remain to be tackled. Here, we review representative molecular and clinical dimensions of gastric cancer.

Predicting outcomes in radiation oncology--multifactorial decision support systems

Abstract: With the emergence of individualized medicine and the increasing amount and complexity of available medical data, a growing need exists for the development of clinical decision-support systems based on prediction models of treatment outcome. In radiation oncology, these models combine both predictive and prognostic data factors from clinical, imaging, molecular and other sources to achieve the highest accuracy to predict tumour response and follow-up event rates. In this Review, we provide an overview of the factors that are correlated with outcome-including survival, recurrence patterns and toxicity-in radiation oncology and discuss the methodology behind the development of prediction models, which is a multistage process. Even after initial development and clinical introduction, a truly useful predictive model will be continuously re-evaluated on different patient datasets from different regions to ensure its population-specific strength. In the future, validated decision-support systems will be fully integrated in the clinic, with data and knowledge being shared in a standardized, instant and global manner.

Past, present, and future of radiotherapy for the benefit of patients.

Abstract: Radiotherapy has been driven by constant technological advances since the discovery of X-rays in 1895. Radiotherapy aims to sculpt the optimal isodose on the tumour volume while sparing normal tissues. The benefits are threefold: patient cure, organ preservation and cost-efficiency. The efficacy and tolerance of radiotherapy were demonstrated by randomized trials in many different types of cancer (including breast, prostate and rectum) with a high level of scientific evidence. Such achievements, of major importance for the quality of life of patients, have been fostered during the past decade by linear accelerators with computer-assisted technology. More recently, these developments were augmented by proton and particle beam radiotherapy, usually combined with surgery and medical treatment in a multidisciplinary and personalized strategy against cancer. This article reviews the timeline of 100 years of radiotherapy with a focus on breakthroughs in the physics of radiotherapy and technology during the past two decades, and the associated clinical benefits.

The future of epigenetic therapy in solid tumours--lessons from the past.

Abstract: The promise of targeting epigenetic abnormalities for cancer therapy has not been realized for solid tumours, although increasing evidence is demonstrating its worth in haematological malignancies. In fact, true clinical efficacy in haematopoietic-related neoplasms has only become evident at low doses of epigenetic-targeting drugs (namely, inhibitors of histone deacetylase and DNA methyltransferases). Describing data from preclinical studies and early clinical trial results, we hypothesize that in using low-dose epigenetic-modulating agents, tumour cells can be reprogrammed, which overrides any immediate cytotoxic and off-target effect observed at high dose. We suggest that such optimization of drug dosing and scheduling of currently available agents could give these agents a prominent place in cancer management--when used alone or in combination with other therapies. If so, optimal use of these known agents might also pave the way for the introduction of other agents that target the epigenome.

Diagnostic and therapeutic avenues for glioblastoma: no longer a dead end?

Abstract: Glioblastomas are heterogeneous neoplasms that are driven by complex signalling pathways, and are among the most aggressive and challenging cancers to treat. Despite standard treatment with resection, radiation and chemotherapy, the prognosis of patients with glioblastomas remains poor. An increasing understanding of the molecular pathogenesis of glioblastomas has stimulated the development of novel therapies, including the use of molecular-targeted agents. Identification and validation of diagnostic, prognostic and predictive biomarkers has led to the advancement of clinical trial design, and identification of glioblastoma subgroups with a more-favourable prognosis and response to therapy. In this Review, we discuss common molecular alterations relevant to the biology of glioblastomas, targeted, antiangiogenic and immunotherapies that have impacted on the treatment of this disease, and the challenges and pitfalls associated with these therapies. In addition, we emphasize current biomarkers relevant to the management of patients with glioblastoma.

Drug rechallenge and treatment beyond progression—implications for drug resistance

Abstract: The established dogma in oncology for managing recurrent or refractory disease dictates that therapy is changed at disease progression, because the cancer is assumed to have become drug-resistant. Drug resistance, whether pre-existing or acquired, is largely thought to be a stable and heritable process; thus, reuse of therapeutic agents that have failed is generally contraindicated. Over the past few decades, clinical evidence has suggested a role for unstable, non-heritable mechanisms of acquired drug resistance pertaining to chemotherapy and targeted agents. There are many examples of circumstances where patients respond to reintroduction of the same therapy (drug rechallenge) after a drug holiday following disease relapse or progression during therapy. Additional, albeit limited, evidence suggests that, in certain circumstances, continuing a therapy beyond disease progression can also have antitumour activity. In this Review, we describe the anticancer agents used in these treatment strategies and discuss the potential mechanisms explaining the apparent tumour re-sensitization with reintroduced or continued therapy. The extensive number of malignancies and drugs that challenge the custom of permanently switching to different drugs at each line of therapy warrants a more in-depth examination of the definitions of disease progression and drug resistance and the resulting implications for patient care.

Aetiology, genetics and prevention of secondary neoplasms in adult cancer survivors

Abstract: Second and higher-order malignancies now comprise about 18% of all incident cancers in the USA, superseding first primary cancers of the breast, lung, and prostate. The occurrence of second malignant neoplasms (SMN) is influenced by a myriad of factors, including the late effects of cancer therapy, shared aetiological factors with the primary cancer (such as tobacco use, excessive alcohol intake, and obesity), genetic predisposition, environmental determinants, host effects, and combinations of factors, including gene-environment interactions. The influence of these factors on SMN in survivors of adult-onset cancer is reviewed here. We also discuss how modifiable behavioural and lifestyle factors may contribute to SMN, and how these factors can be managed. Cancer survivorship provides an opportune time for oncologists and other health-care providers to counsel patients with regard to health promotion, not only to reduce SMN risk, but to minimize co-morbidities. In particular, the importance of smoking cessation, weight control, physical activity, and other factors consonant with adoption of a healthy lifestyle should be consistently emphasized to cancer survivors. Clinicians can also play a critical role by endorsing genetic counselling for selected patients and making referrals to dieticians, exercise trainers, and others to assist with lifestyle change interventions.

Luminal breast cancer: from biology to treatment

Abstract: Oestrogen receptor (ER)-positive--or luminal--tumours represent around two-thirds of all breast cancers. Luminal breast cancer is a highly heterogeneous disease comprising different histologies, gene-expression profiles and mutational patterns, with very varied clinical courses and responses to systemic treatment. Despite adjuvant endocrine therapy and chemotherapy treatment for patients at high risk of relapse, both early and late relapses still occur, a fact that highlights the unmet medical needs of these patients. Ongoing research aims to identify those patients who can be spared adjuvant chemotherapy and who will benefit from extended adjuvant hormone therapy. This research also aims to explore the role of adjuvant bisphosphonates, to interrogate new agents for targeting minimal residual disease, and to address endocrine resistance. Data from next-generation sequencing studies have given us new insight into the biology of luminal breast cancer and, together with advances in preclinical models and the availability of newer targeted agents, have led to the testing of rationally chosen combination treatments in clinical trials. However, a major challenge will be to make sense of the large amount of patient genomic data that is becoming increasingly available. This analysis will be critical to our understanding how intertumour and intratumour heterogeneity can influence treatment response and resistance.

Colorectal cancer screening—optimizing current strategies and new directions

Abstract: The first evidence that screening for colorectal cancer (CRC) could effectively reduce mortality dates back 20 years. However, actual population screening has, in many countries, halted at the level of individual testing and discussions on differences between screening tests. With a wealth of new evidence from various community-based studies looking at test uptake, screening-programme organization and the importance of quality assurance, population screening for CRC is now moving into a new realm, promising better results in terms of reducing CRC-specific morbidity and mortality. Such a shift in the paradigm requires a change from opportunistic, individual testing towards organized population screening with comprehensive monitoring and full-programme quality assurance. To achieve this, a combination of factors--including test characteristics, uptake, screenee autonomy, costs and capacity--must be considered. Thus, evidence from randomized trials comparing different tests must be supplemented by studies of acceptance and uptake to obtain the full picture of the effectiveness (in terms of morbidity, mortality and cost) the different strategies have. In this Review, we discuss a range of screening modalities and describe the factors to be considered to achieve a truly effective population CRC screening programme.

Treatment-related cardiotoxicity in survivors of childhood cancer

Abstract: Treatment advances and higher participation rates in clinical trials have rapidly increased the number of survivors of childhood cancer. However, chemotherapy and radiation treatments are cardiotoxic and can cause cardiomyopathy, conduction defects, myocardial infarction, hypertension, stroke, pulmonary oedema, dyspnoea and exercise intolerance later in life. These cardiotoxic effects are often progressive and irreversible, emphasizing a need for effective prevention and treatment to reduce or avoid cardiotoxicity. Medical interventions, such as angiotensin-converting enzyme inhibitors, β-blockers, and growth hormone therapy, might be used to treat cardiotoxicity in childhood cancer survivors. Preventative strategies should include the use of dexrazoxane, which provides cardioprotection without reducing the oncological efficacy of doxorubicin chemotherapy; less-toxic anthracycline derivatives and the use of antioxidant nutritional supplements might also be beneficial. Continuous-infusion doxorubicin provides no benefit over bolus infusion in children. Identifying patient-related (for example, obesity and hypertension) and drug-related (for example, cumulative dose) risk factors for cardiotoxicity could help tailor treatments to individual patients. However, all survivors of childhood cancer are at increased risk of cardiotoxicity, suggesting that survivor screening recommendations for assessment of global risk of premature cardiovascular disease should apply to all survivors. Optimal, evidence-based monitoring strategies and multiagent preventative treatments still need to be identified.

Advanced-stage pancreatic cancer: therapy options

Abstract: Pancreatic ductal adenocarcinoma is one of the most aggressive cancers, and surgical resection is a requirement for a potential cure. However, the majority of patients are diagnosed with advanced-stage disease, either metastatic (50%) or locally advanced cancer (30%). Although palliative chemotherapy is the standard of care for patients with metastatic disease, management of locally advanced adenocarcinoma is controversial. Several treatment options, including extended surgical resections, neoadjuvant therapy with subsequent resections, as well as palliative radiotherapy and/or chemotherapy, should be considered. However, there is little evidence available to support treatment options for locally advanced disease. As valid predictive biomarkers for stratification of therapy are not available today, future trials need to define the role of the different treatment options. This Review summarizes the current evidence and discusses available treatment options for both locally advanced and metastatic pancreatic adenocarcinoma.

Emerging targeted agents in metastatic breast cancer

Abstract: Extensive preclinical experimentation has conceptually changed the way we perceive breast cancer, with the wide spectrum of genomic alterations governing its malignant progression now being recognized. Functional genomics has helped us identify important genetic defects that can be pharmaceutically targeted in the setting of metastatic disease. Rationally chosen combination regimens are now under clinical investigation. Recent data underline the functional importance of the tumour-associated stroma, with several candidate molecular targets now emerging. Data elucidating a cellular hierarchy within the breast cancer cellular compartment support the existence of a therapy-resistant subpopulation of breast cancer stem cells. Identification of the developmental pathways that dictate their malignant phenotype and use of high- throughput screening techniques are leading to new therapeutic avenues. In this Review, we present the biological rationale for the clinical development of more than 15 different classes of targeted agents in breast cancer, along with evidence supporting rational combinations. However, metastatic breast cancer resembles a Darwinian evolutionary system, with 'driver' mutations and epigenetic changes determining clonal selection according to branching trajectories. This evolution is reflected in the molecular heterogeneity of the disease and poses severe impediments to the successful clinical development of emerging targeted agents.

Circulating tumour cells and cell-free DNA as tools for managing breast cancer.

Abstract: Circulating blood biomarkers promise to become non-invasive real-time surrogates for tumour tissue-based biomarkers. Circulating biomarkers have been investigated as tools for breast cancer diagnosis, the dissection of breast cancer biology and its genetic and clinical heterogeneity, prognostication, prediction and monitoring of therapeutic response and resistance. Circulating tumour cells and cell-free plasma DNA have been analysed in retrospective studies, and the assessment of these biomarkers is being incorporated into clinical trials. As the scope of breast cancer intratumour genetic heterogeneity unravels, the development of robust and standardized methods for the assessment of circulating biomarkers will be essential for the realization of the potentials of personalized medicine. In this Review, we discuss the current status of blood-born biomarkers as surrogates for tissue-based biomarkers, and their burgeoning impact on the management of patients with breast cancer.

The society for immunotherapy of cancer consensus statement on tumour immunotherapy for the treatment of cutaneous melanoma

Abstract: Immunotherapy is associated with durable clinical benefit in patients with melanoma. The goal of this article is to provide evidence-based consensus recommendations for the use of immunotherapy in the clinical management of patients with high-risk and advanced-stage melanoma in the USA. To achieve this goal, the Society for Immunotherapy of Cancer sponsored a panel of melanoma experts--including physicians, nurses, and patient advocates--to develop a consensus for the clinical application of tumour immunotherapy for patients with melanoma. The Institute of Medicine clinical practice guidelines were used as a basis for this consensus development. A systematic literature search was performed for high-impact studies in English between 1992 and 2012 and was supplemented as appropriate by the panel. This consensus report focuses on issues related to patient selection, toxicity management, clinical end points and sequencing or combination of therapy. The literature review and consensus panel voting and discussion were used to generate recommendations for the use of immunotherapy in patients with melanoma, and to assess and rate the strength of the supporting evidence. From the peer-reviewed literature the consensus panel identified a role for interferon-α2b, pegylated-interferon-α2b, interleukin-2 (IL-2) and ipilimumab in the clinical management of melanoma. Expert recommendations for how to incorporate these agents into the therapeutic approach to melanoma are provided in this consensus statement. Tumour immunotherapy is a useful therapeutic strategy in the management of patients with melanoma and evidence-based consensus recommendations for clinical integration are provided and will be updated as warranted.

Paradoxical oncogenesis—the long-term effects of BRAF inhibition in melanoma

Abstract: Although patients with melanoma generally benefit from BRAF or MEK targeted therapies, adverse events can occur on treatment, including the emergence of second malignancies. Evidence suggests unintended or paradoxical activation of MAPK signalling might underlie the majority of these second malignancies. The authors discuss the basis for this paradoxical MAPK activation, and the rationale for novel therapeutic strategies for the management of BRAF-inhibitor-induced neoplasia.

Minimal residual disease in acute myeloid leukaemia.

Abstract: Definition of complete remission in patients with acute myeloid leukaemia (AML) represents a highly heterogeneous state associated with diverse clinical outcomes. The use of minimal residual disease (MRD) as a response criterion allows efficacy assessment of AML therapy. The authors review the characteristics and challenges of the modalities used to detect MRD and outline opportunities to improve clinical use of MRD measurements.

Clinical trials of human papillomavirus vaccines and beyond

Abstract: Human papillomavirus (HPV) is the most common sexually transmitted infectious agent; its 14 oncogenic types are causally associated with 5-10% of all cancers. The major structural HPV protein self-assembles into immunogenic virus-like particles. Two licensed HPV vaccines--the bivalent vaccine comprising HPV types 16 and 18, and the quadrivalent vaccine comprising HPV types 6, 11, 16 and 18--have proven to be safe and efficacious against 6-month-persistent cervical infections of HPV16 and HPV18 and associated precancerous lesions, and both have efficacies of 90-100%. Among baseline HPV-negative adolescent females, vaccine efficacies against the immediate precursor of cervical cancer (intraepithelial neoplasia grade 3) irrespective of HPV type are 93.2% and 43.0% for the bivalent and quadrivalent vaccines, respectively. The quadrivalent vaccine is efficacious (>75% vaccine efficacy) against any of the more-severe precursors of vulval, vaginal and anal cancers. A strong increase in vaccine efficacy with increasing severity of the precancerous lesion is explained by accumulation of the most-oncogenic HPV types 16 and 18 in these lesions. Therefore, prophylactic HPV vaccination will exceed the best results from screening for cancer. With the extremely efficacious prophylactic HPV vaccines, the focus of organized intervention (vaccination and screening) programmes should, however, shift from reducing the HPV disease burden to controlling the prevalence of oncogenic HPV (and nononcogenic HPV) types. Eradication of the major oncogenic HPV types should be pursued.

Beyond aspirin—cancer prevention with statins, metformin and bisphosphonates

Abstract: Cancer risk reduction using pharmacological means is an attractive modern preventive approach that supplements the classical behavioural prevention recommendations. Medications that are commonly used by large populations to treat a variety of common, non-cancer-related, medical situations are an attractive candidate pool. This Review discusses three pharmacological agents with the most evidence for their potential as cancer chemopreventive agents: anti-hypercholesterolaemia medications (statins), an antidiabetic agent (metformin) and antiosteoporosis drugs (bisphosphonates). Data are accumulating to support a significant negative association of certain statins with cancer occurrence or survival in several major tumour sites (mostly gastrointestinal tumours and breast cancer), with an augmented combined effect with aspirin or other non-steroidal anti-inflammatory drugs. Metformin, but not other hypoglycaemic drugs, also seems to have some antitumour growth activity, but the amount of evidence in human studies, mainly in breast cancer, is still limited. Experimental and observational data have identified bisphosphonates as a pharmacological group that could have significant impact on incidence and mortality of more than one subsite of malignancy. At the current level of evidence these potential chemopreventive drugs should be considered in high-risk situations or using the personalized approach of maximizing individual benefits and minimizing the potential for adverse effects with the aid of pharmacogenetic indicators.

Small bowel adenocarcinomas—existing evidence and evolving paradigms

Abstract: Small bowel cancers account for 3% of all gastrointestinal malignancies and small bowel adenocarcinomas represent a third of all small bowel cancers. Rarity of small bowel adenocarcinomas restricts molecular understanding and presents unique diagnostic and therapeutic challenges. Better cross-sectional imaging techniques and development of enteroscopy and capsule endoscopy have facilitated earlier and more-accurate diagnosis. Surgical resection remains the mainstay of therapy for locoregional disease. In the metastatic setting, fluoropyrimidine and oxaliplatin-based chemotherapy has shown clinical benefit in prospective non-randomized trials. Although frequently grouped under the same therapeutic umbrella as large bowel adenocarcinomas, small bowel adenocarcinomas are distinct clinical and molecular entities. Recent progress in molecular characterization has aided our understanding of the pathogenesis of these tumours and holds potential for prospective development of novel targeted therapies. Multi-institutional collaborative efforts directed towards cogent understanding of tumour biology and designing sensible clinical trials are essential for developing improved therapeutic strategies. In this Review, we endeavour to outline an evidence-based approach to present-day management of small bowel adenocarcinoma, describe contemporary challenges and uncover evolving paradigms in the management of these rare 'orphan' neoplasias.

Lung cancer chemoprevention: current status and future prospects

Abstract: Lung cancer is the leading cause of cancer death worldwide, making it an attractive disease for chemoprevention. Although avoidance of tobacco use and smoking cessation will have the greatest impact on lung cancer development, chemoprevention could prove to be very effective, particularly in former smokers. Chemoprevention is the use of agents to reverse or inhibit carcinogenesis and has been successfully applied to other common malignancies. Despite prior studies in lung cancer chemoprevention failing to identify effective agents, we now have the ability to identify high-risk populations, and our understanding of lung tumour and premalignant biology continues to advance. There are distinct histological lesions that can be reproducibly graded as precursors of non-small-cell lung cancer and similar precursor lesions exist for adenocarcinoma. These premalignant lesions are being targeted by chemopreventive agents in current trials and will continue to be studied in the future. In addition, biomarkers that predict risk and response to targeted agents are being investigated and validated. In this Review, we discuss the principles of chemoprevention, data from preclinical models, completed clinical trials and observational studies, and describe new treatments for novel targeted pathways and future chemopreventive efforts.

Palliative care for children with cancer.

Abstract: Over the past two decades, paediatric palliative care has emerged as both a primary approach and as its own medical subspecialty, the overall aim of which is to ease suffering for children with life-threatening illness and their families through a concurrent model of care. However, most discussions have been focused on the transition to palliative care when no realistic hope for cure exists. We believe that, because the course of cancer is so unpredictable, this idea is misleading. Indeed, palliative care is increasingly being recognized as being about not just how to cope with the process of dying, but also about how to engage in living when faced with a life-threatening illness. This article will examine our current understanding of several areas of palliative care, with the ultimate message that palliative care is simply a novel term for the total care of a child and family, an approach that should be applied consistently and concurrently regardless of disease status. By improving familiarity with palliative care and building relationships with palliative care specialists, the paediatric oncology clinician will ensure that the best care possible for children and families is provided, regardless of outcome.

Biopsies: next-generation biospecimens for tailoring therapy.

Abstract: The majority of samples in existing tumour biobanks are surgical specimens of primary tumours. Insights into tumour biology, such as intratumoural heterogeneity, tumour-host crosstalk, and the evolution of the disease during therapy, require biospecimens from the primary tumour and those that reflect the patient's disease in specific contexts. Next-generation 'omics' technologies facilitate deep interrogation of tumours, but the characteristics of the samples can determine the ultimate accuracy of the results. The challenge is to biopsy tumours, in some cases serially over time, ensuring that the samples are representative, viable, and adequate both in quantity and quality for subsequent molecular applications. The collection of next-generation biospecimens, tumours, and blood samples at defined time points during the disease trajectory--either for discovery research or to guide clinical decisions--presents additional challenges and opportunities. From an organizational perspective, it also requires new additions to the multidisciplinary therapeutic team, notably interventional radiologists, molecular pathologists, and bioinformaticians. In this Review, we describe the existing procedures for sample procurement and processing of next-generation biospecimens, and highlight the issues involved in this endeavour, including the ethical, logistical, scientific, informational, and financial challenges accompanying next-generation biobanking.

Appraising iniparib, the PARP inhibitor that never was—what must we learn?

Abstract: Several drugs targeting poly(ADP-ribose) polymerase (PARP) enzymes are under development. Responses have been observed in patients with germline mutations in BRCA1 and BRCA2, with further data supporting antitumour activity of PARP inhibitors in sporadic ovarian cancer. Strategies to identify other predictive biomarkers remain under investigation. Iniparib was purported to be a PARP inhibitor that showed promising results in randomized phase II trials in patients with triple-negative breast cancer. Negative results from a phase III study in this disease setting, however, tempered enthusiasm for this agent. Recently, data from in vitro experiments suggest that iniparib is not only structurally distinct from other described PARP inhibitors, but is also a poor inhibitor of PARP activity. In this context, the negative iniparib phase III data might have erroneously promulgated the notion that PARP inhibition is not an effective therapeutic strategy. Here, we scrutinize the development of iniparib from preclinical studies to registration trials, and identify and discuss the pitfalls in the development of anticancer drugs to prevent future late-stage trial failures.