The Impact of the Gut Microbiome, Environment, and Diet in Early-Onset Colorectal Cancer Development.

Traditionally considered a disease common in the older population, colorectal cancer is increasing in incidence among younger demographics. Evidence suggests that populational- and generational-level shifts in the composition of the human gut microbiome may be tied to the recent trends in gastrointestinal carcinogenesis. This review provides an overview of current research and putative mechanisms behind the rising incidence of colorectal cancer in the younger population, with insight into future interventions that may prevent or reverse the rate of early-onset colorectal carcinoma.

Trends and Determinants of Location of Death Due to Colorectal Cancer in the United States : A Nationwide Study.

BACKGROUND: Colorectal cancer (CRC) is the second leading cause of cancer-related mortality in the United States (US); however, there are limited data on location of death in patients who die from CRC. We examined the trends in location of death and determinants in patients dying from CRC in the US. METHODS: We utilized the Centers for Disease Control and Prevention Wide-Ranging Online Data for Epidemiologic Research database to extract nationwide data on underlying cause of death as CRC. A multinomial logistic regression was performed to assess associations between clinico-sociodemographic characteristics and location of death. RESULTS: There were 850,750 deaths due to CRC from 2003 to 2019. There was a gradual decrease in deaths in hospital, nursing home, or outpatient facility/emergency department over time and an increase in deaths at home and in hospice. Relative to White decedents, Black, Asian, and American Indian/Alaska Native decedents were less likely to die at home and in hospice compared with hospitals. Individuals with lower educational status also had a lower risk of dying at home or in hospice compared with in hospitals. CONCLUSIONS: The gradual shift in location of death of patients who die of CRC from institutionalized settings to home and hospice is a promising trend and reflects the prioritization of patient goals for end-of-life care by healthcare providers. However, there are existing sociodemographic disparities in access to deaths at home and in hospice, which emphasizes the need for policy interventions to reduce health inequity in end-of-life care for CRC.

Weakly supervised segmentation models as explainable radiological classifiers for lung tumour detection on CT images.

PURPOSE: Interpretability is essential for reliable convolutional neural network (CNN) image classifiers in radiological applications. We describe a weakly supervised segmentation model that learns to delineate the target object, trained with only image-level labels ("image contains object" or "image does not contain object"), presenting a different approach towards explainable object detectors for radiological imaging tasks. METHODS: A weakly supervised Unet architecture (WSUnet) was trained to learn lung tumour segmentation from image-level labelled data. WSUnet generates voxel probability maps with a Unet and then constructs an image-level prediction by global max-pooling, thereby facilitating image-level training. WSUnet's voxel-level predictions were compared to traditional model interpretation techniques (class activation mapping, integrated gradients and occlusion sensitivity) in CT data from three institutions (training/validation: n = 412; testing: n = 142). Methods were compared using voxel-level discrimination metrics and clinical value was assessed with a clinician preference survey on data from external institutions. RESULTS: Despite the absence of voxel-level labels in training, WSUnet's voxel-level predictions localised tumours precisely in both validation (precision: 0.77, 95% CI: [0.76-0.80]; dice: 0.43, 95% CI: [0.39-0.46]), and external testing (precision: 0.78, 95% CI: [0.76-0.81]; dice: 0.33, 95% CI: [0.32-0.35]). WSUnet's voxel-level discrimination outperformed the best comparator in validation (area under precision recall curve (AUPR): 0.55, 95% CI: [0.49-0.56] vs. 0.23, 95% CI: [0.21-0.25]) and testing (AUPR: 0.40, 95% CI: [0.38-0.41] vs. 0.36, 95% CI: [0.34-0.37]). Clinicians preferred WSUnet predictions in most instances (clinician preference rate: 0.72 95% CI: [0.68-0.77]). CONCLUSION: Weakly supervised segmentation is a viable approach by which explainable object detection models may be developed for medical imaging. CRITICAL RELEVANCE STATEMENT: WSUnet learns to segment images at voxel level, training only with image-level labels. A Unet backbone first generates a voxel-level probability map and then extracts the maximum voxel prediction as the image-level prediction. Thus, training uses only image-level annotations, reducing human workload. WSUnet's voxel-level predictions provide a causally verifiable explanation for its image-level prediction, improving interpretability. KEY POINTS: • Explainability and interpretability are essential for reliable medical image classifiers. • This study applies weakly supervised segmentation to generate explainable image classifiers. • The weakly supervised Unet inherently explains its image-level predictions at voxel level.

Autism care pathway in Europe.

BACKGROUND: Autism is a lifelong complex neurodevelopmental condition that affects brain development and behaviour with significant consequences for everyday life. Despite its personal, familial, and societal impact, Europe-wide harmonised guidelines are still lacking for early detection, diagnosis, and intervention, leading to an overall unsatisfactory autistic person and carer journey. METHODS: The care pathway for autistic children and adolescents was analysed in Italy, Spain and the UK from the perspective of carers (using a survey aimed at caregivers of autistic children 0-18 years old), the autistic community, and professionals in order to identify major barriers (treatment gaps) preventing carers from receiving information, support, and timely screening/diagnosis and intervention. RESULTS: Across all three countries, analysis of the current care pathway showed: long waits from the time carers raised their first concerns about a child's development and/or behaviour until screening and confirmed diagnosis; delayed or no access to intervention once a diagnosis was confirmed; limited information about autism and how to access early detection services; and deficient support for families throughout the journey. CONCLUSIONS: These findings call for policy harmonisation in Europe to shorten long wait times for diagnosis and intervention and therefore, improve autistic people and their families' journey experience and quality of life.

Economic analysis of early intervention for autistic children: findings from four case studies in England, Ireland, Italy, and Spain.

BACKGROUND: Many autistic children experience difficulties in their communication and language skills development, with consequences for social development into adulthood, often resulting in challenges over the life-course and high economic impacts for individuals, families, and society. The Preschool Autism Communication Trial (PACT) intervention is effective in terms of improved social communication and some secondary outcomes. A previously published within-trial economic analysis found that results at 13 months did not support its cost-effectiveness. We modeled cost-effectiveness over 6 years and across four European countries. METHODS: Using simulation modeling, we built on economic analyses in the original trial, exploring longer-term cost-effectiveness at 6 years (in England). We adapted our model to undertake an economic analysis of PACT in Ireland, Italy, and Spain. Data on resource use were taken from the original trial and a more recent Irish observational study. RESULTS: PACT is cost-saving over time from a societal perspective, even though we confirmed that, at 13 months post-delivery, PACT is more expensive than usual treatment (across all countries) when given to preschool autistic children. After 6 years, we found that PACT has lower costs than usual treatment in terms of unpaid care provided by parents (in all countries). Also, if we consider only out-of-pocket expenses from an Irish study, PACT costs less than usual treatment. DISCUSSION: PACT may be recommended as a cost-saving early intervention for families with an autistic child.

Autism with co-occurring epilepsy care pathway in Europe.

BACKGROUND: Autism and epilepsy often occur together. Epilepsy and other associated conditions have a substantial impact on the well-being of autistic people and their families, reduce quality of life, and increase premature mortality. Despite this, there is a lack of studies investigating the care pathway of autistic children with co-occurring epilepsy in Europe. METHODS: We analyzed the care pathway for autistic children with associated epilepsy in Italy, Spain, and the United Kingdom from the perspective of caregivers (using a survey aimed at caregivers of autistic children 0-18 years old), the autistic community, and professionals, in order to identify major barriers preventing caregivers and autistic children from receiving timely screening and treatment of possible co-occurring epilepsy. RESULTS: Across all three countries, an analysis of the current care pathway showed a lack of systematic screening of epilepsy in all autistic children, lack of treatment of co-occurring epilepsy, and inappropriate use of antiepileptic drugs. A major challenge is the lack of evidence-based harmonized guidelines for autism with co-occurring epilepsy in these countries. CONCLUSIONS: Our findings show both heterogeneity and major gaps in the care pathway for autism with associated epilepsy and the great efforts that caregivers must make for timely screening, diagnosis, and adequate management of epilepsy in autistic children. We call for policy harmonization in Europe in order to improve the experiences and quality of life of autistic people and their families.

Economic Evaluation of anti-epileptic Medicines for Autistic Children with Epilepsy.

We examine the cost-effectiveness of treating epilepsy with anti-epileptic medicines in autistic children, looking at impacts on healthcare providers (in England, Ireland, Italy and Spain) and children's families (in Ireland). We find carbamazepine to be the most cost-effective drug to try first in children with newly diagnosed focal seizures. For England and Spain, oxcarbazepine is the most cost-effective treatment when taken as additional treatment for those children whose response to monotherapy is suboptimal. In Ireland and Italy, gabapentin is the most cost-effective option. Our additional scenario analysis presents the aggregate cost to families with autistic children who are being treated for epilepsy: this cost is considerably higher than healthcare provider expenditure.

Diagnostic Sensitivity of Unenhanced CT for Cerebral Venous Thrombosis: Can Clot Density Measurement Replace CT Venogram?

Objectives Cerebral venous sinus thrombosis is an important cause of stroke in young adults. Noncontrast-enhanced CT head (NECT) is almost always the first investigation. Our objectives were as follows: 1. How accurately does venous sinus density on NECT predict the presence of clot on CT venogram (CTV)? 2. Whether repeated measurements changed the confidence? 3. How many venous sinus thrombus would be missed if we do not do a CTV? 4. Can clot density measurement replace CTV? Methods Multicenter case-control study was designed with data from seven hospitals. Inclusion criteria: all CT and magnetic resonance imaging venograms with a prior NECT, performed between 1.1.2018 and 31.12.2018 (12 months), were included. Hounsfield unit (HU) values were calculated at the site of highest density on the NECT. Logistic regression analysis was performed using STATA. Result Two-hundred seventy-seven cases met the criteria with 33 positive cerebral venous thrombosis (density on NECT 60-92 HU) and 244 negative examinations (density on NECT 31-68 HU). Area under the curve for average clot density on NECT was 0.9984. Conclusion We found a strong relationship between sinus density on NECT and outcome of CTV. Repeating density measurements did not add any predictive value or changed outcome. Advances in Knowledge Density 70 HU or higher on NECT always resulted in a positive CTV but would miss a fifth of the positives. Cutoff at 60 HU would not miss any but result in significant false positives. An efficient option could be to limit CTV to sinus densities 60 to 70 HU only. However, a larger study would be required for such change in practice.

Surgical resection as a predictor of cancer-specific survival by stage at diagnosis and cancer type, United States, 2006-2015.

BACKGROUND: When solid tumors are amenable to definitive resection, clinical outcomes are generally superior to when those tumors are inoperable. However, the population-level cancer survival benefit of eligibility for surgery by cancer stage has not yet been quantified. METHODS: Using Surveillance, Epidemiology and End Results data allowing us to identify patients who were deemed eligible for and received surgical resection, we examined the stage-specific association of surgical resection with 12-year cancer-specific survival. The 12-year endpoint was selected to maximize follow-up time and thereby minimize the influence of lead time bias. RESULTS: Across a variety of solid tumor types, earlier stage at diagnosis allowed for surgical intervention at a much higher rate than later-stage diagnosis. At every stage, surgical intervention was associated with a substantially higher rate of 12-year cancer-specific survival, with absolute differences of up to 51% for stage I, 51% for stage II, and 44% for stage III cancer, and stage-specific mortality relative risks of 3.6, 2.4, and 1.7, respectively. CONCLUSIONS: Diagnosis of solid cancers in early stages often enables surgical resection, which reduces the risk of death from cancer. Receipt of surgical resection is an informative endpoint that is strongly associated with long-term cancer-specific survival at every stage.

Immune Microenvironment in Sporadic Early-Onset versus Average-Onset Colorectal Cancer.

The incidence of left-sided colon and rectal cancer in young people are increasing worldwide, but its causes are poorly understood. It is not clear if the tumor microenvironment is dependent on age of onset, and little is known about the composition of tumor-infiltrating T cells in early-onset colorectal cancer (EOCRC). To address this, we investigated T-cell subsets and performed gene expression immune profiling in sporadic EOCRC tumors and matched average-onset colorectal cancer (AOCRC) tumors. Left-sided colon and rectal tumors from 40 cases were analyzed; 20 EOCRC (<45 years) patients were matched 1:1 to AOCRC (70-75 years) patients by gender, tumor location, and stage. Cases with germline pathogenic variants, inflammatory bowel disease or neoadjuvant-treated tumors were excluded. For T cells in tumors and stroma, a multiplex immunofluorescence assay combined with digital image analysis and machine learning algorithms was used. Immunological mediators in the tumor microenvironment were assessed by NanoString gene expression profiling of mRNA. Immunofluorescence revealed no significant difference between EOCRC and AOCRC with regard to infiltration of total T cells, conventional CD4+ and CD8+ T cells, regulatory T cells, or γδ T cells. Most T cells were located in the stroma in both EOCRC and AOCRC. Immune profiling by gene expression revealed higher expression in AOCRC of the immunoregulatory cytokine IL-10, the inhibitory NK cell receptors KIR3DL3 and KLRB1 (CD161), and IFN-a7 (IFNA7). In contrast, the interferon-induced gene IFIT2 was more highly expressed in EOCRC. However, in a global analysis of 770 tumor immunity genes, no significant differences could be detected. T-cell infiltration and expression of inflammatory mediators are similar in EOCRC and AOCRC. This may indicate that the immune response to cancer in left colon and rectum is not related to age of onset and that EOCRC is likely not driven by immune response deficiency.

Benefits and harms of interventions to improve anxiety, depression, and other mental health outcomes for autistic people: A systematic review and network meta-analysis of randomised controlled trials.

LAY ABSTRACT: Nearly three out of four autistic people experience mental health problems such as stress, anxiety or depression. The research already done does not guide us on how best to prevent or treat mental health problems for autistic people. Our aim was to look at the benefits and harms of different interventions on mental health outcomes in autistic people. We searched all the published randomised controlled trials (RCTs) about interventions for mental health conditions in autistic people until 17 October 2020. We also searched for RCTs that were not published in peer-reviewed journals. These were obtained from registers of clinical trials online. We then combined the information from all these trials using advanced statistical methods to analyse how good the interventions are. Seventy-one studies (3630 participants) provided information for this research. The studies reported how participants were responding to the intervention for only a short period of time. The trials did not report which interventions worked for people with intellectual disability. In people without intellectual disability, some forms of cognitive behavioural therapy and mindfulness therapy may be helpful. However, further research is necessary. Many trials used medications to target core features of autism rather than targeting mental health conditions, but these medications did not help autistic people. Until we have more evidence, treatment of mental health conditions in autistic people should follow the evidence available for non-autistic people. We plan to widely disseminate the findings to healthcare professionals through medical journals and conferences and contact other groups representing autistic people.

Positron Emission Tomography/Magnetic Resonance Imaging (PET/MRI) Versus the Standard of Care Imaging in the Diagnosis of Peritoneal Carcinomatosis.

OBJECTIVE: To compare positron emission tomography (PET)/magnetic resonance imaging (MRI) to the standard of care imaging (SCI) for the diagnosis of peritoneal carcinomatosis (PC) in primary abdominopelvic malignancies. SUMMARY BACKGROUND DATA: Identifying PC impacts prognosis and management of multiple cancer types. METHODS: Adult subjects were prospectively and consecutively enrolled from April 2019 to January 2021. Inclusion criteria were: 1) acquisition of whole-body contrast-enhanced (CE) 18F-fluorodeoxyglucose PET/MRI, 2) pathologically confirmed primary abdominopelvic malignancies. Exclusion criteria were: 1) greater than 4 weeks interval between SCI and PET/MRI, 2) unavailable follow-up. SCI consisted of whole-body CE PET/computed tomography (CT) with diagnostic quality CT, and/or CE-CT of the abdomen and pelvis, and/or CE-MRI of the abdomen±pelvis. If available, pathology or surgical findings served as the reference standard, otherwise, imaging followup was used. When SCI and PET/MRI results disagreed, medical records were checked for management changes. Follow-up data were collected until August 2021. RESULTS: One hundred sixty-four subjects were included, 85 (52%) were female, and the median age was 60 years (interquartile range 50-69). At a subject level, PET/MRI had higher sensitivity (0.97, 95% CI 0.86-1.00) than SCI (0.54, 95% CI 0.37-0.71), P < 0.001, without a difference in specificity, of 0.95 (95% CI 0.90-0.98) for PET/MRI and 0.98 (95% CI 0.93-1.00) for SCI, P » 0.250. PET/MRI and SCI results disagreed in 19 cases. In 5/19 (26%) of the discordant cases, PET/MRI findings consistent with PC missed on SCI led to management changes. CONCLUSION: PET/MRI improves detection of PC compared with SCI which frequently changes management.

Molecular Basis of Extramural Vascular Invasion (EMVI) in Colorectal Carcinoma.

BACKGROUND: Extramural vascular invasion (EMVI) is a known poor prognostic factor in colorectal carcinoma; however, its molecular basis has not been defined. This study aimed to assess the expression of molecular markers in EMVI positive colorectal carcinoma to understand their tumor microenvironment. METHODS: Immunohistochemistry was performed on tissue microarrays of surgically resected colorectal cancer specimens for immunological markers, and BRAFV600E mutation (and on the tissue blocks for mismatch repair proteins). Automated quantification was used for CD8, LAG3, FOXP3, PU1, and CD163, and manual quantification was used for PDL1, HLA I markers (beta-2 microglobulin, HC10), and HLA II. The Wilcoxon rank-sum test was used to compare EMVI positive and negative tumors. A logistic regression model was fitted to assess the predictive effect of biomarkers on EMVI. RESULTS: There were 340 EMVI positive and 678 EMVI negative chemo naïve tumors. PDL1 was barely expressed on tumor cells (median 0) in the entire cohort. We found a significantly lower expression of CD8, LAG3, FOXP3, PU1 cells, PDL1 positive macrophages, and beta-2 microglobulin on tumor cells in the EMVI positive subset (p ≤ 0.001). There was no association of BRAFV600E or deficient mismatch repair proteins (dMMR) with EMVI. PU1 (OR 0.8, 0.7-0.9) and low PDL1 (OR 1.6, 1.1-2.3) independently predicted EMVI on multivariate logistic regression among all biomarkers examined. CONCLUSION: There is a generalized blunting of immune response in EMVI positive colorectal carcinoma, which may contribute to a worse prognosis. Tumor-associated macrophages seem to play the most significant role in determining EMVI.

Patient Survival With ypT0N+ Following Neoadjuvant Therapy in Rectal Cancer.

BACKGROUND: After neoadjuvant therapy, pathologic analysis of rectal cancer resected specimens may show a complete response in the primary tissue cancer with residual tumor in the lymph nodes (ypT0N+). OBJECTIVES: The aim of this study was to describe the 5-year overall survival and factors associated with survival of ypT0N+ patients with rectal cancer who had neoadjuvant therapy followed by surgery and to compare these patients' survival with patients in other pathologic categories. DESIGN: We conducted a retrospective analysis. SETTINGS: We used the National Cancer Database. PATIENTS: We identified patients with rectal adenocarcinoma who underwent total neoadjuvant therapy or neoadjuvant chemoradiation followed by surgery between 2006 and 2016. Besides ypT0N+, 5 pathologic categories were identified: ypT0N0, ypT1-2N0, ypT3-4N0, ypT1-2N+, and ypT3-4N+. MAIN OUTCOME MEASURE: The primary outcome measure was 5-year overall survival. RESULTS: We included 30,751 patients with rectal adenocarcinoma. A total of 342 patients developed ypT0N+, of whom 181 (52.9%) received total neoadjuvant therapy. Among patients who received total neoadjuvant therapy, developing ypT0N+ was associated with a lower 5-year overall survival than ypT0N0 and ypT1-2N0. However, ypT0N+ disease was associated with a higher 5-year overall survival than ypT3-4N+. There were no differences in 5-year overall survival between ypT0N+ and ypT3-4N0 or ypT1-2N+. Similar findings were noticed among patients who received neoadjuvant chemoradiation and adjuvant chemotherapy. For patients with ypT0N+, older age, male gender, and higher number of positive lymph nodes were all associated with a decrease in the overall survival. LIMITATIONS: Limitations include the retrospective nature of this study, lack of variables describing the chemotherapy and radiation regimens used, and paucity of data on disease-specific survival or recurrence. CONCLUSIONS: Developing ypT0N+ was associated with a lower 5-year overall survival than ypT0N0 and ypT1-2N0. However, it was associated with a higher 5-year overall survival than ypT3-4N+. See Video Abstract at http://links.lww.com/DCR/B863 . SOBREVIDA DE LOS PACIENTES CON YPTN DESPUS DE LA TERAPIA NEOADYUVANTE EN EL CNCER DE RECTO: ANTECEDENTES:Después del tratamiento neoadyuvante en el cáncer de recto bajo, el análisis patológico de la pieza operatoria resecada, puede mostrar una respuesta patológica completa del tumor primario pero con tumor residual en los ganglios linfáticos (ypT0N+).OBJETIVOS:Describir la sobrevida general a 5 años y los factores asociados con la sobrevida de los pacientes ypT0N+ con cáncer de recto, que recibieron terapia neoadyuvante seguida de cirugía y comparar la sobrevida de estos pacientes con la de pacientes con otros estadios patológicos.DISEÑO:Realizamos un análisis retrospectivo.AJUSTES:Utilizamos la base de datos nacional del cáncer.PACIENTES:Identificamos pacientes con adenocarcinoma de recto que se sometieron a terapia neoadyuvante total, seguida de cirugía entre 2006 y 2016. Además de ypT0N +, se identificaron 5 categorías patológicas: ypT0N0, ypT1-2N0, ypT3-4N0, ypT1-2N+, e ypT3-4N+.PRINCIPAL MEDIDA DE RESULTADO:La medida de resultado principal fue la supervivencia general a 5 años.RESULTADOS:Se incluyeron 30.751 pacientes con adenocarcinoma de recto. Un total de 342 pacientes desarrollaron ypT0N+, de los cuales 181 (52,9%) recibieron terapia neoadyuvante total. Entre los pacientes que recibieron terapia neoadyuvante total, el desarrollo de ypT0N+ se asoció con una supervivencia general a 5 años más baja que ypT0N0 e ypT1-2N0. Sin embargo, la enfermedad ypT0N+ se asoció con una supervivencia general a 5 años más alta que ypT3-4N+. No hubo diferencias en la supervivencia global a 5 años entre ypT0N+ y ypT3-4N0 o ypT1-2N+. Se observaron hallazgos similares entre los pacientes que recibieron terapia neoadyuvante y quimioterapia adyuvante. Para los pacientes con ypT0N+, la edad avanzada, el sexo masculino y un mayor número de ganglios linfáticos positivos se asociaron con una disminución en la supervivencia general.LIMITACIONES:Las limitaciones incluyen la naturaleza retrospectiva del estudio, la falta de variables que describan los regímenes de quimioterapia y radiación utilizados y la escasez de datos sobre la supervivencia o la recurrencia específicas de la enfermedad.CONCLUSIONES:El desarrollo de ypT0N+ se asoció con una supervivencia general a 5 años más baja que ypT0N0 e ypT1-2N0. Sin embargo, se asoció con una supervivencia global a 5 años más alta que ypT3-4N+. Consulte Video Resumen en http://links.lww.com/DCR/B863 . (Traducción-Dr. Rodrigo Azolas ).

The Use of Single-Agent Versus Multiple-Agent Concurrent Chemoradiotherapy in the Treatment of Locally Advanced Rectal Cancer.

PURPOSE: The use of concurrent chemoradiotherapy is frequently recommended in the treatment of locally advanced rectal cancer; however, the ideal chemotherapy regimen remains unknown, and there is variability in chemotherapy agents used among different institutions. We sought to examine differences in overall survival between patients receiving single versus multiple-agent concurrent chemoradiotherapy. METHODS: The National Cancer Database was used to identify 31,025 patients with rectal cancer who received concurrent chemoradiotherapy between 01/2006 and 12/2016. We compared patients who received single-agent chemotherapy with those who received multiple-agent concurrent chemoradiotherapy. The primary outcome of interest was overall survival. The groups were compared using univariate analysis and Cox proportional hazard models to adjust for potential confounding factors. RESULTS: 18,544 patients received single-agent and 12,481 patients received multiple-agent chemotherapy. The former were older with more comorbidities as evidenced by their higher Charlson-Deyo Scores. Those receiving multiple-agent chemotherapy were more likely to have clinical stage III disease (52.9% vs 43.3%, p < 0.001) and less likely to have well-differentiated cancer (6.9% vs 7.7%, p < 0.001). The rates of negative resection margin were identical (p = 0.225) between the two groups. On multivariable analysis after adjusting for comorbidities, radiation dose, and resection margins, single-agent chemotherapy was associated with worse overall survival (HR 1.09, 95% CI 1.057-1.124, p < 0.001). CONCLUSION: Multiple-agent chemoradiotherapy is associated with improved overall survival in locally advanced rectal cancer; however, chemotherapy regimen does not affect resection margins. The modest overall survival benefit with multiple-agent chemotherapy must be balanced with the potential associated toxicity.