The host cytoskeleton: a key regulator of early HIV-1 infection

Due to its central role in cell biology, the cytoskeleton is a key regulator of viral infection, influencing nearly every step of the viral life cycle. In this review, we will discuss the role of two key components of the cytoskeleton, namely the actin and microtubule networks in early HIV-1 infection. We will discuss key contributions to processes ranging from the attachment and entry of viral particles at the cell surface to their arrival and import into the nucleus and identify areas where further research into this complex relationship may yield new insights into HIV-1 pathogenesis.

Editorial: Muscles at the expense of liver injury. Is it worth it?

This article is linked to Nash et al paper. To view this article, visit https://doi.org/10.1111/apt.17906

A Case Report of Anesthesia-induced Diffuse Alveolar Hemorrhage Presenting to the Emergency Department

Introduction

The inhaled anesthetic sevoflurane is an uncommon etiology of diffuse alveolar hemorrhage (DAH). As DAH typically presents in the inpatient, postoperative setting, it has been infrequently reported in the anesthesiology literature and, to our knowledge, has not been reported in the emergency medicine literature to date.

Case Report

We describe the presentation of a young, healthy male in respiratory distress to a busy urban emergency department (ED) after an outpatient surgical procedure. We highlight the etiology of post-anesthesia DAH and the acute management of this rare diagnosis in the ED.

Conclusion

With outpatient surgical centers becoming an increasingly popular option for lower risk procedures, emergency physicians would benefit from understanding this presentation and its pathophysiology.

Frequent Friers: Outcomes in Patients Who Receive Multiple Courses of Lung SBRT

PURPOSE/OBJECTIVE(S)

Stereotactic body radiation therapy (SBRT) is a definitive therapy for early-stage non-small cell lung cancer and solitary pulmonary metastases with high tolerability and excellent survival rates. With longer survival and patients developing subsequent primaries or oligometastatic disease, patients are receiving multiple repeat lung SBRT courses. This study aims to assess safety and efficacy of high-frequency SBRT (HF-SBRT) to the lung, defined as >3 courses.

MATERIALS/METHODS

A retrospective review was performed of patients who received >3 courses of lung SBRT. Logistic regression was performed to identify predictors of radiation pneumonitis (RP) and worsening pulmonary function (WPF). Local control (LC) and overall survival (OS) were evaluated using the Kaplan-Meier method.

RESULTS

Ninety-four courses of HF-SBRT to the lung were identified among 28 patients. 78% of patients received 3 SBRT courses, 12% received 4 courses, and 7.1% received >5 courses. Median follow-up was 4.4 years. Median age at time of treatment was 73 years-old; 58% males; 42% had an underlying pulmonary comorbidity; 39% prior lung surgery; 52% history of cardiac disease; 52% prior tobacco use; median ECOG 0. Median SBRT dose was 48 Gy. Median interval between courses was 5.6 months. Zero patients experienced greater than grade 2 acute CTCAE v5 toxicity. 7.2% (7) of patients developed RP at median time of 2.6 months [IQR: 1.4,7.4]; grade 1: 3 patients, grade 2: 1 patient, grade 3: 2 patients. Of patients who developed RP, 42% (3) went on to receive further SBRT without experiencing significant adverse events (AEs). History of pulmonary disease, prior lung surgery, and history of tobacco use strongly correlated with WPF but not RP (WPF p-values: <0.001, 0.003, <0.001, respectively). History of cardiac disease did not correlate with WPF or RP. Receiving bilateral lung SBRT treatment (vs unilateral) trended towards correlation with WPF (p = 0.06) and RP (p = 0.08). Time between SBRT courses did not significantly differ for those who developed RP (p = 0.62) or WPF (p = 0.42). No individual or plan sum dosimetric constraint (GTV, PTV, unilateral lung V5, lung V10, lung V20, unilateral mean lung dose, or total lung V20) significantly differed in those who experienced RP. WPF correlated with the plan sum unilateral lung V10 (p = 0.05). LC at 1-year was 100%, 1 local failure occurred at 13 months; 2-year OS was 91.7%, median OS 5.4 years.

CONCLUSION

Overall, HF-SBRT was well tolerated. Development of RP did not correlate with a specific individual or plan sum dosimetric parameter, with patients receiving subsequent courses of SBRT without increased AEs. WPF increasingly occurred with subsequent SBRT courses and correlated with unilateral plan sum V10. This study suggests that in appropriately selected patients, SBRT after RP can still be provided as definitive care, while further studies should validate this and focus attention on mitigating long-term WPF in patients who receive HF-SBRT.

A brief history of the development and use of vulcanised rubber in dentistry

Until the late nineteenth century, denture baseplates and removable orthodontic appliances were usually made of gold. Though now largely forgotten, the discovery of vulcanised rubber was instrumental in making these forms of dental treatment widely available to the general public. While Charles Goodyear is recognised for his role in the development of vulcanite in America, that of Thomas Hancock in the UK is less well-known.

Prehospital Airway Management Training and Education: An NAEMSP Position Statement and Resource Document

AbstractAirway management competency extends beyond technical skills to encompass a comprehensive approach to optimize patient outcomes. Initial and continuing education for airway management must therefore extend beyond a narrow focus on psychomotor skills and task completion to include appreciation of underlying pathophysiology, clinical judgment, and higher-order decision making. NAEMSP recommends:Active engagement in deliberate practice should be the guiding approach for developing and maintaining competence in airway management.EMS learners and clinicians must be educated in an escalating approach to airway management, where basic airway maneuvers form the central focus.Educational activities should extend beyond fundamental knowledge to focus on the development of clinical judgment.Optimization of patient outcomes should be valued over performance of individual airway management skills.Credentialing and continuing education activities in airway management are essential to advance clinicians beyond entry-level competency.Initial and continuing education programs should be responsive to advances in the evidence base and maintain adaptability to re-assess content and expected outcomes on a continual basis.

Prehospital Trauma Airway Management: An NAEMSP Position Statement and Resource Document

Definitive management of trauma is not possible in the out-of-hospital environment. Rapid treatment and transport of trauma casualties to a trauma center are vital to improve survival and outcomes. Prioritization and management of airway, oxygenation, ventilation, protection from gross aspiration, and physiologic optimization must be balanced against timely patient delivery to definitive care. The optimal prehospital airway management strategy for trauma has not been clearly defined; the best choice should be patient-specific. NAEMSP recommends:The approach to airway management and the choice of airway interventions in a trauma patient requires an iterative, individualized assessment that considers patient, clinician, and environmental factors.Optimal trauma airway management should focus on meeting the goals of adequate oxygenation and ventilation rather than on specific interventions. Emergency medical services (EMS) clinicians should perform frequent reassessments to determine if there is a need to escalate from basic to advanced airway interventions.Management of immediately life-threatening injuries should take priority over advanced airway insertion.Drug-assisted airway management should be considered within a comprehensive algorithm incorporating failed airway options and balanced management of pain, agitation, and delirium.EMS medical directors must be highly engaged in assuring clinician competence in trauma airway assessment, management, and interventions.

WAKsing plant immunity, waning diseases

With the requirement to breed more productive crop plants in order to feed a growing global population, compounded by increasingly widespread resistance to pesticides exhibited by pathogens, plant immunity is becoming an increasingly important area of research. Of the genes that contribute to disease resistance, the wall-associated receptor-like kinases (WAKs) are increasingly shown to play a major role, in addition to their contribution to plant growth and development or tolerance to abiotic stresses. Being transmembrane proteins, WAKs form a central pillar of a plant cell's ability to monitor and interact with the extracellular environment. Found in both dicots and monocots, WAKs have been implicated in defence against pathogens with diverse lifestyles and contribute to plant immunity in a variety of ways. Whilst some act as cell surface-localized immune receptors recognizing either pathogen- or plant-derived invasion molecules (e.g. effectors or damage-associated molecular patterns, respectively), others promote innate immunity through cell wall modification and strengthening, thus limiting pathogen intrusion. The ability of some WAKs to provide both durable resistance against pathogens and other agronomic benefits makes this gene family important targets in the development of future crop ideotypes and important to a greater understanding of the complexity and robustness of plant immunity.

Remarkable recent changes in the genetic diversity of the avirulence gene AvrStb6 in global populations of the wheat pathogen Zymoseptoria tritici

Septoria tritici blotch (STB), caused by the fungus Zymoseptoria tritici, is one of the most economically important diseases of wheat. Recently, both factors of a gene-for-gene interaction between Z. tritici and wheat, the wheat receptor-like kinase Stb6 and the Z. tritici secreted effector protein AvrStb6, have been identified. Previous analyses revealed a high diversity of AvrStb6 haplotypes present in earlier Z. tritici isolate collections, with up to c.18% of analysed isolates possessing the avirulence isoform of AvrStb6 identical to that originally identified in the reference isolate IPO323. With Stb6 present in many commercial wheat cultivars globally, we aimed to assess potential changes in AvrStb6 genetic diversity and the incidence of haplotypes allowing evasion of Stb6-mediated resistance in more recent Z. tritici populations. Here we show, using targeted resequencing of AvrStb6, that this gene is universally present in field isolates sampled from major wheat-growing regions of the world in 2013-2017. However, in contrast to the data from previous AvrStb6 population studies, we report a complete absence of the originally described avirulence isoform of AvrStb6 amongst modern Z. tritici isolates. Moreover, a remarkably small number of haplotypes, each encoding AvrStb6 protein isoforms conditioning virulence on Stb6-containing wheat, were found to predominate among modern Z. tritici isolates. A single virulence isoform of AvrStb6 was found to be particularly abundant throughout the global population. These findings indicate that, despite the ability of Z. tritici to sexually reproduce on resistant hosts, AvrStb6 avirulence haplotypes tend to be eliminated in subsequent populations.

Antibody responses after first and second Covid-19 vaccination in patients with chronic lymphocytic leukaemia

B-cell chronic lymphocytic leukaemia (CLL) is associated with immunosuppression and patients are at increased clinical risk following SARS-CoV-2 infection. Covid-19 vaccines offer the potential for protection against severe infection but relatively little is known regarding the profile of the antibody response following first or second vaccination. We studied spike-specific antibody responses following first and/or second Covid-19 vaccination in 299 patients with CLL compared with healthy donors. 286 patients underwent extended interval (10-12 week) vaccination. 154 patients received the BNT162b2 mRNA vaccine and 145 patients received ChAdOx1. Blood samples were taken either by venepuncture or as dried blood spots on filter paper. Spike-specific antibody responses were detectable in 34% of patients with CLL after one vaccine (n = 267) compared to 94% in healthy donors with antibody titres 104-fold lower in the patient group. Antibody responses increased to 75% after second vaccine (n = 55), compared to 100% in healthy donors, although titres remained lower. Multivariate analysis showed that current treatment with BTK inhibitors or IgA deficiency were independently associated with failure to generate an antibody response after the second vaccine. This work supports the need for optimisation of vaccination strategy in patients with CLL including the potential utility of booster vaccines.

How decision-making about euthanasia for animals is taught to Australasian veterinary students

This study set out to explore how euthanasia decision-making for animals was taught to students in eight Australasian veterinary schools. A questionnaire-style interview guide was used by a representative at each university to interview educators. Educators were interviewed about their teaching of euthanasia decision-making for four categories of animals: livestock, equine, companion and avian/wildlife. Using thematic analysis, the terms provided by participants to describe how (mode of teaching) and what (specific content) they taught to students were categorised. Information about content was categorised into human-centred factors that influence decision-making, and animal-based indicators used to directly inform decision-making. All eight representatives reported some teaching relevant to euthanasia decision-making at their university for livestock, companion animal and avian/wildlife. One representative reported no such teaching for equid animals at their university. Observation of a euthanasia case was rarely reported as a teaching method. Five universities reported multiple modes of teaching relevant information, while two universities made use of modalities that could be described as opportunistic teaching (e.g., 'Discussion of clinical cases'). Factors taught at most universities included financial considerations, and that it is the owner's decision to make, while animal-based indicators taught included QoL/animal welfare, prognosis and behaviour change. Overall, most universities used a variety of methods to cover relevant material, usually including lectures and several other approaches for all animal types. However, because two universities relied on presentation of clinical cases, not all students at these veterinary schools will be exposed to make, or assist in making, euthanasia decisions.

Ambient-pressure endstation of the Versatile Soft X-ray (VerSoX) beamline at Diamond Light Source

The ambient-pressure endstation and branchline of the Versatile Soft X-ray (VerSoX) beamline B07 at Diamond Light Source serves a very diverse user community studying heterogeneous catalysts, pharmaceuticals and biomaterials under realistic conditions, liquids and ices, and novel electronic, photonic and battery materials. The instrument facilitates studies of the near-surface chemical composition, electronic and geometric structure of a variety of samples using X-ray photoelectron spectroscopy (XPS) and near-edge X-ray absorption fine-structure (NEXAFS) spectroscopy in the photon energy range from 170 eV to 2800 eV. The beamline provides a resolving power hν/Δ(hν) > 5000 at a photon flux > 10¹⁰ photons s^-1 over most of its energy range. By operating the optical elements in a low-pressure oxygen atmosphere, carbon contamination can be almost completely eliminated, which makes the beamline particularly suitable for carbon K-edge NEXAFS. The endstation can be operated at pressures up to 100 mbar, whereby XPS can be routinely performed up to 30 mbar. A selection of typical data demonstrates the capability of the instrument to analyse details of the surface composition of solid samples under ambient-pressure conditions using XPS and NEXAFS. In addition, it offers a convenient way of analysing the gas phase through X-ray absorption spectroscopy. Short XPS spectra can be measured at a time scale of tens of seconds. The shortest data acquisition times for NEXAFS are around 0.5 s per data point.

How management of grief associated with ending the life of an animal is taught to Australasian veterinary students

OBJECTIVE

Veterinarians have an important role in supporting and understanding their clients' grief. Veterinary schools have a duty to teach students how best to manage grief - both that of the students/future veterinarians and the clients. This study explores how grief management, associated with ending the life of an animal, was taught to students in eight Australasian veterinary schools.

METHODS

A questionnaire-style interview guide was used by a representative at each university to conduct structured interviews with educators in a snowball sampling approach. Educators were interviewed about the teaching of grief management for four categories of animals: livestock, equine, companion and avian/wildlife. The terms used by participants to describe what they taught were grouped into common themes. Teaching was defined by individual participants and included structured and unstructured approaches. The stage in the degree (preclinical or clinical years) that grief management was taught in the veterinary curriculum and by whom (e.g. clinicians or psychologists) is also described.

RESULTS

Grief management was taught more in preclinical than clinical years. However, due to how grief was characterised, much of this teaching was general 'nonspecific' teaching that included all categories of animals. Client grief was taught more generically, whereas, grief of veterinarians was taught using specific examples given by clinicians.

CONCLUSION

A more robust end-of-life (EoL) management curriculum that includes all aspects of grief management is likely to increase job satisfaction, client happiness and professional satisfaction.

A-75 Predicting neurocognitive impairment using the Green’s Medical Symptom Validity Test dementia profile formula

Objective

The Green’s Medical Symptom Validity Test (MSVT) is a measure of performance validity and has a formula to help distinguish genuine cognitive impairment from suboptimal engagement. The current study used the MSVT “dementia profile” formula to discriminate patients with no neurocognitive disorder (no NCD), mild neurocognitive disorder (mild NCD), and major neurocognitive disorder (major NCD).

Method

198 patients who were seen for comprehensive outpatient neuropsychological testing and passed all MSVT validity measures were included in the study. Specifically, participants included 103 persons with no NCD, 62 diagnosed with a mild NCD, and 33 with major NCD, who were collectively 58% male, with a mean age of 52-years-old (SD = 16.1) and mean education of 14.5 years (SD = 2.5).

Results

The difference score between easy and hard MSVT subtests predicted group assignment (r = .57, p < .001) and effectively differentiated the three groups (p < .001). Mean difference scores of both groups with diagnosed NCD exceeded recommended criteria suggestive of genuine cognitive impairment, with the differences score of major NCD being greater (p < .01) than the mild NCD. Group differences remained significant (p < .001) after adjusting for the effects of age and education. When the NCD groups were compared to the no diagnosis group, ROC curve analysis produced an AUC of .84, with a sensitivity of .72 and specificity of .83.

Conclusions

Findings from this study validate the established difference score between easy and hard subtests of the MSVT, and suggest that the difference score on a valid MSVT profile yields diagnostically relevant information pertaining to the level of an individual’s neurocognitive impairment.

Spontaneous post-partum rupture of bilateral ovarian arteries treated with transarterial embolization

Rupture of an ovarian artery aneurysm in the peripartum period occurs in both traumatic and atraumatic settings. To our knowledge, this is the first reported case of spontaneous atraumatic rupture of the bilateral ovarian arteries. This report describes a multiparous recently post-partum patient with abdominal pain and signs of hemodynamic compromise, the sequela of hemoperitoneum from ruptured bilateral ovarian arteries. With a multidisciplinary approach, this patient was successfully treated with transarterial embolization.

Helicopter emergency medical services for adults with major trauma

BACKGROUND

Although helicopters are presently an integral part of trauma systems in most developed nations, previous reviews and studies to date have raised questions about which groups of traumatically injured people derive the greatest benefit.

OBJECTIVES

To determine if helicopter emergency medical services (HEMS) transport, compared with ground emergency medical services (GEMS) transport, is associated with improved morbidity and mortality for adults with major trauma.

SEARCH METHODS

We ran the most recent search on 29 April 2015. We searched the Cochrane Injuries Group's Specialised Register, The Cochrane Library (Cochrane Central Register of Controlled Trials; CENTRAL), MEDLINE (OvidSP), EMBASE Classic + EMBASE (OvidSP), CINAHL Plus (EBSCOhost), four other sources, and clinical trials registers. We screened reference lists.

SELECTION CRITERIA

Eligible trials included randomized controlled trials (RCTs) and nonrandomized intervention studies. We also evaluated nonrandomized studies (NRS), including controlled trials and cohort studies. Each study was required to have a GEMS comparison group. An Injury Severity Score (ISS) of at least 15 or an equivalent marker for injury severity was required. We included adults age 16 years or older.

DATA COLLECTION AND ANALYSIS

Three review authors independently extracted data and assessed the risk of bias of included studies. We applied the Downs and Black quality assessment tool for NRS. We analyzed the results in a narrative review, and with studies grouped by methodology and injury type. We constructed 'Summary of findings' tables in accordance with the GRADE Working Group criteria.

MAIN RESULTS

This review includes 38 studies, of which 34 studies examined survival following transportation by HEMS compared with GEMS for adults with major trauma. Four studies were of inter-facility transfer to a higher level trauma center by HEMS compared with GEMS. All studies were NRS; we found no RCTs. The primary outcome was survival at hospital discharge. We calculated unadjusted mortality using data from 282,258 people from 28 of the 38 studies included in the primary analysis. Overall, there was considerable heterogeneity and we could not determine an accurate estimate of overall effect.Based on the unadjusted mortality data from six trials that focused on traumatic brain injury, there was no decreased risk of death with HEMS. Twenty-one studies used multivariate regression to adjust for confounding. Results varied, some studies found a benefit of HEMS while others did not. Trauma-Related Injury Severity Score (TRISS)-based analysis methods were used in 14 studies; studies showed survival benefits in both the HEMS and GEMS groups as compared with MTOS. We found no studies evaluating the secondary outcome, morbidity, as assessed by quality-adjusted life years (QALYs) and disability-adjusted life years (DALYs). Four studies suggested a small to moderate benefit when HEMS was used to transfer people to higher level trauma centers. Road traffic and helicopter crashes are adverse effects which can occur with either method of transport. Data regarding safety were not available in any of the included studies. Overall, the quality of the included studies was very low as assessed by the GRADE Working Group criteria.

AUTHORS' CONCLUSIONS

Due to the methodological weakness of the available literature, and the considerable heterogeneity of effects and study methodologies, we could not determine an accurate composite estimate of the benefit of HEMS. Although some of the 19 multivariate regression studies indicated improved survival associated with HEMS, others did not. This was also the case for the TRISS-based studies. All were subject to a low quality of evidence as assessed by the GRADE Working Group criteria due to their nonrandomized design. The question of which elements of HEMS may be beneficial has not been fully answered. The results from this review provide motivation for future work in this area. This includes an ongoing need for diligent reporting of research methods, which is imperative for transparency and to maximize the potential utility of results. Large, multicenter studies are warranted as these will help produce more robust estimates of treatment effects. Future work in this area should also examine the costs and safety of HEMS, since multiple contextual determinants must be considered when evaluating the effects of HEMS for adults with major trauma.

Strategies for engaging with future radiation protection professionals: a public outreach case study

It is evident that there is a nuclear skills shortage within the UK, and logically it can be assumed that the shortfall extends to the radiation protection arena. Plans for nuclear new-build and the decommissioning of existing nuclear sites will require many more people with radiological knowledge and practical competencies. This converts to a nuclear industry requirement in the order of 1000 new recruits per year over at least the next ten years, mainly as new apprentices and graduates. At the same time, the strong demand for persons with radiation protection know-how in the non-nuclear and health care sectors is unlikely to diminish. The task of filling this skills gap is a significant one and it will require a determined effort from many UK stakeholders. The Society for Radiological Protection (SRP) has adopted a strategy in recent years to help address this skills gap. The aim is to engage the interest of secondary school students in the science of radiation and inspire them to follow a career in radiation protection. This paper presents the reasoning behind this strategy and, in an 'outreach case study', describes the establishment of the annual SRP Schools Event. This event is becoming an important addition to the national efforts aimed at increasing the numbers of skilled UK radiation protection professionals over the forthcoming decades.

Distinct phenotype of hepatotoxicity associated with illicit use of anabolic androgenic steroids

BACKGROUND

We have observed an increase in hepatotoxicity (DILI) reporting related to the use of anabolic androgenic steroids (AAS) for bodybuilding.

AIM

To characterise phenotype presentation, outcome and severity of AAS DILI.

METHODS

Data on 25 cases of AAS DILI reported to the Spanish (20) and Latin-American (5) DILI Registries were collated and compared with previously published cases.

RESULTS

AAS DILI increased from representing less than 1% of the total cases in the Spanish DILI Registry in the period 2001-2009 to 8% in 2010-2013. Young men (mean age 32 years), requiring hospitalisation, hepatocellular injury and jaundice were predominating features among the AAS cases. AAS DILI caused significantly higher bilirubin values independent of type of damage when compared to other drug classes (P = 0.001). Furthermore, the cholestatic AAS cases presented significantly higher mean peak bilirubin (P = 0.029) and serum creatinine values (P = 0.0002), compared to the hepatocellular cases. In a logistic regression model, the interaction between peak bilirubin values and cholestatic damage was associated with the development of AAS-induced acute kidney impairment (AKI) [OR 1.26 (95% CI: 1.035-1.526); P = 0.021], with 21.5 ×ULN being the best bilirubin cut-off point for predicting AKI risk (AUCROC 0.92). No fatalities occurred.

CONCLUSIONS

Illicit recreational AAS use is a growing cause of reported DILI that can lead to severe hepatic and renal injury. AAS DILI is associated with a distinct phenotype, characterised by considerable bilirubin elevations independent of type of damage. Although hepatocellular injury predominates, acute kidney injury develops in cholestatic cases with pronounced jaundice.

KRAS mutations in non-small-cell lung cancer and colorectal cancer: implications for EGFR-targeted therapies

BACKGROUND

KRAS mutations are associated with diverse biologic functions as well as prognostic and predictive impact in non-small cell-lung cancer (NSCLC) and colorectal cancer (CRC). In CRC, benefit from monoclonal antibody therapies targeting EGFR is generally limited to patients whose tumors have wild-type (WT) KRAS, whereas data suggest that this association is not present for NSCLC. We hypothesized that the unique tobacco-related carcinogenesis of NSCLC results in a divergence of KRAS MT genotype compared with CRC, contributing to differences in outcomes from EGFR-targeted therapies.

MATERIAL AND METHODS

Tumor from 2603 patients (838 CRC and 1765 NSCLC) was analyzed for KRAS mutations. DNA was extracted from microdissected formalin-fixed-paraffin-embedded specimens (FFPE) and 7 different base substitutions in codons 12 and 13 of KRAS were determined.

RESULTS

KRAS mutation genotype differed significantly between NSCLC and CRC in frequency (25% vs. 39%; p<0.001), smoking-associated G>T transversions (73% versus 27%; p<0.001), and ratio of transversions to transitions (3.5 vs. 0.79; p<0.001). In NSCLC GLY12Cys mutations, resulting from a codon 12 GGT>TGT substitution, were observed in 44% compared to 10% for CRC. In contrast, codon 12 or 13 GLY>ASP substitutions (resulting in a G>A transition) were more frequent in CRC (42%) compared with NSCLC (21%).

CONCLUSION

In this large dataset, KRAS mutation patterns are quantitatively and qualitatively distinct between NSCLC and CRC, reflecting in part differences in tobacco-related carcinogenesis. In light of differences in predictive value for EGFR-directed monoclonal antibody therapy and prognosis for specific KRAS mutations between NSCLC and CRC, these data provide an underlying biologic rationale.