Is short-course radiotherapy and total neoadjuvant therapy the new standard of care in locally advanced rectal cancer? A sensitivity analysis of the RAPIDO clinical trial.

BACKGROUND: The results of the RAPIDO trial have been accepted as evidence in favour of short-course radiotherapy (SC-RT) followed by chemotherapy before total mesorectal excision in high-risk locally advanced rectal cancer. A noteworthy concern is that the RAPIDO trial did not ensure that all patients in the control arm received adjuvant chemotherapy. This may bias statistical estimates in favour of the experimental arm if adjuvant chemotherapy is active in rectal cancer. Moreover, the 5-year update revealed an increase in the risk of local relapse in the experimental arm. MATERIALS AND METHODS: We carried out sensitivity analyses to determine how plausible effects of adjuvant chemotherapy, adjusted by the proportion of patients in the standard arm receiving adjuvant treatment, would have influenced the observed treatment effect estimate of the RAPIDO trial. The most plausible values for the benefit of adjuvant chemotherapy were determined by Bayesian re-analysis of a prior meta-analysis. RESULTS: The meta-analysis suggested that oxaliplatin/fluorouracil-based adjuvant chemotherapy may improve disease-free survival (DFS) in rectal cancer although the signal is weak [hazard ratio (HR) 0.84, 95% credible interval, 0.57-1.15]; probability of benefit (HR <1) was 91.2%. In the sensitivity analysis, the HR for disease-related treatment failure would remain <1, thus favouring total neoadjuvant therapy (TNT), on most occasions, but the null hypothesis would not have been rejected in various credible settings. For the RAPIDO data to be consistent with the null effect, a moderate benefit of adjuvant chemotherapy (HR for DFS between 0.75 and 0.80) and 70%-80% of exposed participants would suffice. CONCLUSION: The decision to make adjuvant chemotherapy optional in the standard arm may have biased the results in favour of the experimental arm, in a scenario in which TNT does not offset the increase in local recurrences after SC-RT.

The fasted and post-prandial physiological responses of the Patagonian blennie Eleginops maclovinus.

Eleginops maclovinus is a native species with potential for Chilean aquaculture. Understanding the variations between the post-prandial and fasted metabolic responses can contribute to improving the aquaculture of this species. This study aimed to characterize variations in intermediate metabolism during the course of the day in the liver, serum, and gills of fed and unfed fish. For this, 72 fish were assigned to two experimental groups, "fed" and "fasted". The first group was fed "ad libitum" at 8.30, while the fasted group was not fed for 24 h. Samples were taken from both groups at 9:00, and every 2 h: 11:00, 13:00, 15:00, 17:00, and 19:00. In the fed group, food spent a long time in the gastrointestinal tract, with a large increase in stomach size and without evidence of complete emptying of the stomach at 19:00 (10.5 h post-feeding). In serum, the levels of amino acids, glucose, and triglycerides presented significant differences with peak levels at different times of day in the fed group. The cortisol in the fasted group presented a diurnal pattern with high levels during the morning and very low levels after 13:00, while in the fed group, the high cortisol variability did not allow a clear pattern to be established. In the liver, the effect of time on the enzymatic activity of the intermediary metabolism was greater compared to the effect of feeding. In the liver, enzyme activity decreased at later hours of the day, while glycogen levels increased at later hours of the day in both groups: but its levels were higher in the fed group. In gills, as well as in the liver, time had a greater effect than feeding on intermediate metabolism, since feeding only had a significant effect on the levels of hexokinase, lactate, and amino acids, suggesting an effect on carbohydrate metabolism. Meanwhile, time significantly affected the levels of Na+, K+-ATPase, glutamate dehydrogenase, aspartate aminotransferase, amino acids, and proteins, suggesting an effect on amino acid metabolism. In conclusion, the intermediate metabolism of E. maclovinus presents variations according to the time of day, with an increased metabolism during the morning and decreased metabolism as the day progresses, especially at the hepatic level. The gill tissue, despite not being a metabolic organ, presents feeding-dependent variations in its metabolism. Additional studies will be required to corroborate if coordinating a feeding strategy during the first hours of the day when metabolism is greater would improve the growth of E. maclovinus.

Intestinal variation of serotonin, melatonin, and digestive enzymes activities along food passage time through GIT in Salmo salar fed with supplemented diets with tryptophan and melatonin.

In teleosts, peripheral serotonin (5-HT) and melatonin (MEL) are synthesised in the gastrointestinal tract (GIT) and regulate secretion and motility processes. Their production is regulated by diet and the passage of food through the GIT. This study aimed to evaluate how intestinal 5-HT, melatonin, and the activity of digestive enzymes varied with food passage time through GIT in Atlantic salmon (Salmo salar). We fed fish diets supplemented with tryptophan and melatonin (L-Trp 2.5% and MEL 0.01%) and measured the activity of digestive enzymes (amylase, lipase, and total protease) in the pyloric caeca, midgut, and hindgut at different times after feeding. 5-HT levels increased in all GIT portions and diets at 120 min post-intake and were highest in the pyloric caeca. Intestinal enzymatic activity was varied with diet, post-intake time and in different intestinal portions. In conclusion, food passage time directly affects GIT 5-HT secretion and digestive enzyme activity in S. salar, and diet composition regulates S. salar GIT function.

The osmotic response capacity of the Antarctic fish Harpagifer antarcticus is insufficient to cope with projected temperature and salinity under climate change.

Over the last decades, climate change has intensified. Temperatures have increased and seawater has become "fresher" in Antarctica, affecting fish such as Harpagifer antarcticus. Thus, this study aimed to evaluate changes in the osmoregulatory response of the Antarctic notothenioid fish Harpagifer antarcticus and evaluate how it will cope with the future climate change and environmental conditions in the Antarctic, and in the hypothetical case that its geographical distribution will be extended to the Magellanes region. The present study was undertaken to determine the interaction between temperature and salinity tolerance (2 °C and 33 psu as the control group, the experimental groups were 5, 8, and 11 °C and 28 and 23 psu) and their effect on the osmoregulatory status of H. antarcticus. We evaluated changes in gill-kidney-intestine NKA activity, gene expression of NKAα, NKCC, CFTR, Aquaporins 1 and 8 in the same tissues, muscle water percentage, and plasma osmolality to evaluate osmoregulatory responses. Plasma osmolality decreased with high temperature, also the gill-kidney-intestine NKA activity, gene expression of NKA α, NKCC, CFTR, Aquaporins 1, and 8 were modified by temperature and salinity. We demonstrated that H. antarcticus can not live in the Magallanes region, due to its incapacity to put up with temperatures over 5 °C and with over 8 °C being catastrophic.

Hypoxia modulates the transcriptional immunological response in Oncorhynchus kisutch.

Oncorhynchus kisutch is the third most cultivated salmonid species in the Chilean salmon industry and its farming conditions are characterised by high stocking density leading to the generation of high levels of organic matter (food - feces) and decomposition. In addition to the increasingly frequent hypoxic oceanographic events, these inappropriate farming conditions increase the demand for oxygen within the fish farm pen and lead to the appearance of hypoxic events that are harmful to fish.This study aimed to evaluate the stress response (cortisol) and transcription of genes involved in the immune response in head kidney and spleen of Oncorhynchus kisutch subjected to chronic hypoxic stress conditions. The fish were exposed to 100%, 60%, 50%, 35%, and 25% of DO for 28 days, then the blood (plasma), head kidney and spleen were removed. We observed mortality in the 25% DO group at days 15 and 20. Plasma cortisol increased significantly under 35% and 25% DO conditions compared to control. Transcription of Toll-like receptors (TLR1, TLR5M, TLR8, and TLR9) and cytokines (IL-1ß, IL6, IL10, TNF-α) increased in the head kidney only in the 50% DO group, while in spleen there was an increase of these markers in the conditions of 60%, 35%, and 25% DO. As for the markers involved in cell-mediated immunity, CD4-MHCII and CD8-MHCI do not have a clear expression pattern, although there was down-regulation in MHCII transcription in the head kidney, in all the hypoxia conditions evaluated. Finally, IgM transcription was increased in the spleen in all hypoxia conditions, although it wasn't always statistically significant compared to the control. These results indicate that chronic hypoxia induces the stress response, increasing plasma cortisol levels and modulating the transcription of genes involved in the innate and adaptive immune response. The expression patterns were tissue-specific, indicating that the degree of hypoxia differentially affects the transcription of genes involved in the immune response of Oncorhynchus kisutch.

Assessment of antibodies against three zoonotic bacteria and associated risk factors in pig farms in Colombia. / Evaluación de anticuerpos frente a tres bacterias zoonóticas y factores de riesgo asociados en explotaciones porcinas de Colombia.

The aim of this study was to determine the seroprevalence of Salmonella spp., Mycobacterium bovis and Brucella spp., together with associated risk factors, in pigs from various farms in seven regions of Colombia. A total of 350 blood samples were obtained from pigs at different stages in the production cycle of 23 farms, which were tested using the enzyme-linked immunosorbent assay (ELISA) diagnostic kits Pigtype®-Salmonella Ab (Qiagen®, Hilden, Germany), INgezim TB porcine and INgezim Brucella porcine (Ingenasa®, Madrid, Spain). The overall seroprevalence for Salmonella spp. was 42.85% (n = 150) and, for M. bovis, it was 5.42% (n = 19). No positive samples were detected for Brucella spp. In the farms evaluated, the presence of pests, such as rodents, was found to be the management variable with a statistically significant association with seropositivity for Salmonella spp. and M. bovis. The results suggest that, at some point in the primary production cycle, pigs came into contact with zoonotic bacteria, resulting in seropositivity, which may pose a risk to public health and national pig production.

Les auteurs présentent les résultats d'une étude menée en Colombie pour déterminer la prévalence sérologique de Salmonella spp., de Mycobacterium bovis et de Brucella spp. et d'identifier les facteurs de risques associés chez les porcs de différents élevages répartis dans sept régions du pays. Au total, 350 prélèvements sanguins de porcs en différentes phases du cycle de production et provenant de 23 exploitations ont été analysés en utilisant les kits de diagnostic suivants : test immuno-enzymatique (ELISA) Pigtype®-Salmonella Ab (Qiagen®, Hilden, Allemagne), INgezim TB porcina et INgezim Brucella porcina (Ingenasa®, Madrid, Espagne). La prévalence sérologique globale de Salmonella spp. était de 42,85 % (n = 150) et celle de M. bovis de 5,42 % (n = 19) ; aucun échantillon n'a été trouvé positif pour Brucella spp. En ce qui concerne les facteurs en lien avec la gestion des élevages, une corrélation significative au plan statistique a été observée dans les exploitations étudiées entre la présence de ravageurs (rongeurs notamment) et l'apparition d'anticorps dirigés contre Salmonella spp. et M. bovis. Les résultats obtenus laissent penser que les porcs ont été exposés à ces bactéries zoonotiques à un moment ou un autre du cycle de production primaire, ce qui a déclenché l'apparition d'anticorps ; il s'agit d'une situation à risque tant pour la santé publique que pour la filière porcine du pays.

El objetivo del presente estudio fue determinar la seroprevalencia respectoa Salmonella spp., Mycobacterium bovis y Brucella spp., junto con los factores de riesgo asociados, en porcinos de diferentes explotaciones de producción en siete regiones de Colombia. Se obtuvieron 350 muestras sanguíneas de porcinos de diferentes etapas del ciclo productivo provenientes de 23 explotaciones,y estas fueron analizadas utilizando los estuches de ensayo inmunoenzimático (ELISA) para diagnóstico Pigtype®-Salmonella Ab (Qiagen®, Hilden, Alemania), INgezim TB porcina e INgezim Brucella porcina (Ingenasa®, Madrid, España). La seroprevalencia general respecto a Salmonella spp. fue del 42,85% (n = 150),y para M. bovis, del 5,42% (n = 19); no se detectó ninguna muestra positiva respecto a Brucella spp. Se determinó que en las explotaciones evaluadas, la presencia de plagas, como los roedores, fue la variable de manejo con asociación estadísticamente significativa a la seropositividad respecto a Salmonella spp.y a M. bovis. Los resultados obtenidos sugieren que, en algún momento del ciclo de producción primaria, los cerdos estuvieron en contacto con las bacterias zoonóticas frente a las que se obtuvo seropositividad, lo cual puede representar un riesgo para la salud pública y la producción porcina a nivel nacional.

Context matters-consensus molecular subtypes of colorectal cancer as biomarkers for clinical trials.

The Colorectal Cancer Subtyping Consortium identified four gene expression consensus molecular subtypes, CMS1 (immune), CMS2 (canonical), CMS3 (metabolic), and CMS4 (mesenchymal), using multiple microarray or RNA-sequencing datasets of primary tumor samples mainly from early stage colon cancer patients. Consequently, rectal tumors and stage IV tumors (possibly reflective of more aggressive disease) were underrepresented, and no chemo- and/or radiotherapy pretreated samples or metastatic lesions were included. In view of their possible effect on gene expression and consequently subtype classification, sample source and treatments received by the patients before collection must be carefully considered when applying the classifier to new datasets. Recently, several correlative analyses of clinical trials demonstrated the applicability of this classification to the metastatic setting, confirmed the prognostic value of CMS subtypes after relapse and hinted at differential sensitivity to treatments. Here, we discuss why contexts and equivocal factors need to be taken into account when analyzing clinical trial data, including potential selection biases, type of platform, and type of algorithm used for subtype prediction. This perspective article facilitates both our clinical and research understanding of the application of this classifier to expedite subtype-based clinical trials.

Phase II study of high-sensitivity genotyping of KRAS, NRAS, BRAF and PIK3CA to ultra-select metastatic colorectal cancer patients for panitumumab plus FOLFIRI: the ULTRA trial.

BACKGROUND: Several studies show the importance of accurately quantifying not only KRAS and other low-abundant mutations because benefits of anti-EGFR therapies may depend on certain sensitivity thresholds. We assessed whether ultra-selection of patients using a high-sensitive digital PCR (dPCR) to determine KRAS, NRAS, BRAF and PIK3CA status can improve clinical outcomes of panitumumab plus FOLFIRI. PATIENTS AND METHODS: This was a single-arm phase II trial that analysed 38 KRAS, NRAS, BRAF and PIK3CA hotspots in tumour tissues of irinotecan-resistant metastatic colorectal cancer patients who received panitumumab plus FOLFIRI until disease progression or early withdrawal. Mutation profiles were identified by nanofluidic dPCR and correlated with clinical outcomes (ORR, overall response rate; PFS, progression-free survival; OS, overall survival) using cut-offs from 0% to 5%. A quantitative PCR (qPCR) analysis was also performed. RESULTS: Seventy-two evaluable patients were enrolled. RAS (KRAS/NRAS) mutations were detected in 23 (32%) patients and RAS/BRAF mutations in 25 (35%) by dPCR, while they were detected in 7 (10%) and 11 (15%) patients, respectively, by qPCR. PIK3CA mutations were not considered in the analyses as they were only detected in 2 (3%) patients by dPCR and in 1 (1%) patient by qPCR. The use of different dPCR cut-offs for RAS (KRAS/NRAS) and RAS/BRAF analyses translated into differential clinical outcomes. The highest ORR, PFS and OS in wild-type patients with their lowest values in patients with mutations were achieved with a 5% cut-off. We observed similar outcomes in RAS/BRAF wild-type and mutant patients defined by qPCR. CONCLUSIONS: High-sensitive dPCR accurately identified patients with KRAS, NRAS, BRAF and PIK3CA mutations. The optimal RAS/BRAF mutational cut-off for outcome prediction is 5%, which explains that the predictive performance of qPCR was not improved by dPCR. The biological and clinical implications of low-frequent mutated alleles warrant further investigations. CLINICALTRIALS.GOV NUMBER: NCT01704703. EUDRACT NUMBER: 2012-001955-38.

Ultra-selection of metastatic colorectal cancer patients using next-generation sequencing to improve clinical efficacy of anti-EGFR therapy.

BACKGROUND: Extended RAS analysis is mandatory in metastatic colorectal cancer (mCRC) patients. The optimal threshold of RAS mutated subclones to identify patients most likely to benefit from antiepidermal growth factor receptor (EGFR) therapy is controversial. Our aim was to assess the clinical impact of detecting mutations in RAS, BRAF, PIK3CA and EGFRS492R in basal tissue tumour samples by using a highly sensitive next-generation sequencing (NGS) technology in mCRC patients treated with chemotherapy plus anti-EGFR or anti-vascular endothelial growth factor. PATIENTS AND METHODS: Five hundred and eighty-one tumour samples from untreated mCRC patients from 7 clinical studies were collected. Mutational analysis was carried out by standard-of-care (therascreen pyro) with a sensitivity detection of 5% mutant allele fraction (MAF), and compared with NGS technology using 454GS Junior platform (Roche Applied Science, Germany) with a sensitivity of 1%. Molecular results were correlated with clinical outcomes. RESULTS: After quality assessment, 380 samples were evaluable for molecular analysis. Standard-of-care mutational analysis detected RAS, BRAFV600E or PIK3CA mutations in 56.05% of samples compared with 69.21% by NGS (P = 0.00018). NGS identified coexistence of multiple low-frequency mutant alleles in 96 of the 263 mutated cases (36.5%; range 2-7). Response rate (RR), progression-free survival (PFS) and overall survival (OS) were increasingly improved in patients with RAS wild-type, RAS/BRAF wild-type or quadruple (KRAS/NRAS/BRAF/PIK3CA) wild-type tumours treated with anti-EGFR, assessed by standard-of-care. No additional benefit in RR, PFS or OS was observed by increasing the detection threshold to 1% by NGS. An inverse correlation between the MAF of the most prevalent mutation detected by NGS and anti-EGFR response was observed (P = 0.039). EGFRS492Rmutation was not detected in untreated samples. CONCLUSIONS: No improvement in the selection of patients for anti-EGFR therapy was obtained by adjusting the mutation detection threshold in tissue samples from 5% to 1% MAF. Response to anti-EGFR was significantly better in patients with quadruple wild-type tumours.

Tempo and mode in coevolution of Agave sensu lato (Agavoideae, Asparagaceae) and its bat pollinators, Glossophaginae (Phyllostomidae).

The genus Agave sensu lato contains ca. 211 described species, many of which are considered keystone species because of their ecological dominance and the quantity of resources they provide with their massive, nectar-rich inflorescences. The large diversity of Agave species has been hypothesized as being related to their reproductive strategy (predominantly monocarpic) and diverse pollinators (e.g., bats, hummingbirds, hawkmoths). In particular, Agave species provide resources that a few genera of nectar feeding bats from the subfamily Glosophaginae are dependent upon. To explore a possible coevolutionary relationship between Agave and the bat species that pollinate them, we calibrated molecular phylogenies of both groups and looked for a correlation in their dates of divergence. One coding and two non-coding regions of the chloroplast genome were sequenced from 49 species of the Agavoideae (Asparagaceae), and the mitochondrial gene Cyt-b and nuclear coding gene RAG2 were either sequenced or obtained from gene bank for 120 Phyllostomid bats. Results from the analyses indicate that Agave sensu lato is a young genus (estimated crown age 2.7-8.5/stem age 4.6-12.3 Ma), with an increasing diversification rate, and the highest speciation rate among Agavoideae's clades. The origin of the Glossophaginae bats (stem age 20.3-23.5 Ma) occurred prior to the stem age of Agave sensu lato, while the origin of the current pollinators of Agave species, members of the genera Glossophaga, Leptonycteris, Anoura, Choeronyscus, Musonycteris and Choeronycteris, was estimated to be around 6.3-16.2 Ma, overlapping with the stem age of Agave sensu lato, supporting the hypothesis of diffuse coevolution.

Genotype-based selection of treatment of patients with advanced colorectal cancer (SETICC): a pharmacogenetic-based randomized phase II trial.

Background: There has been little progress toward personalized therapy for patients with metastatic colorectal cancer (mCRC). TYMS-3' untranslated region (UTR) 6 bp ins/del and ERCC1-118C/T polymorphisms were previously reported to facilitate selecting patients for fluoropyrimidine-based treatment in combination with oxaliplatin as first-line therapy. We assessed the utility of these markers in selecting therapy for patients with mCRC. Patients and methods: This randomized, open-label phase II trial compared bevacizumab plus XELOX (control) versus treatment tailored according to TYMS-3'UTR 6 bp ins/del and ERCC1-118C/T polymorphisms. Patients randomized to the experimental treatment received bevacizumab plus FUOX, FUIRI, XELIRI, or XELOX depending on their combination of favorable polymorphisms for FUOX treatment (TYMS-3'UTR ins/del or del/del; ERCC1-118T/T). Progression-free survival (PFS) was the primary end point. Results: Overall, 195 patients were randomized (control n = 65; experimental n = 130). The primary objective was not met: median PFS was 9.4 months in the control group and 10.1 months in the experimental group (P = 0.745). Median overall survival was similar in both groups (16.5 versus 19.1 months, respectively; P = 0.797). Patients in the experimental group had a significantly higher overall response rate (ORR; 65% versus 47% in the control group; P = 0.042) and R0 resection rate (86% versus 44%, respectively; P = 0.018). Neuropathy, hand-foot syndrome, thrombocytopenia, and dysesthesia were significantly less common in the experimental group. Conclusions: This study did not show survival benefits after treatment personalization based on polymorphisms in mCRC. However, the improved ORR and R0 resection rate and fewer disabling toxicities suggest that tailoring therapy by TYMS-3'UTR and ERCC1-118 polymorphisms warrants further investigation in patients with mCRC. ClinicalTrials.gov: NCT01071655.

Prediction of pathological response to neoadjuvant treatment in rectal cancer with a two-protein immunohistochemical score derived from stromal gene-profiling.

BACKGROUND: Preoperative chemoradiotherapy followed by surgical mesorectal resection is the standard of care for locally advanced rectal carcinomas. Yet, predicting that patients will respond to treatment remains an unmet clinical challenge. EXPERIMENTAL DESIGN: Using laser-capture microdissection we isolated RNA from stroma and tumour glands from prospective pre-treatment samples (n = 15). Transcriptomic profiles were obtained hybridising PrimeView Affymetrix arrays. We modelled a carcinoma-associated fibroblast-specific genes filtering data using GSE39396. RESULTS: The analysis of differentially expressed genes of stroma/tumour glands from responder and non-responder patients shows that most changes were associated with the stromal compartment; codifying mainly for extracellular matrix and ribosomal components. We built a carcinoma-associated fibroblast (CAF) specific classifier with genes showing changes in expression according to the tumour regression grade (FN1, COL3A1, COL1A1, MMP2 and IGFBP5). We assessed these five genes at the protein level by means of immunohistochemical staining in a patient's cohort (n = 38). For predictive purposes we used a leave-one-out cross-validated model with a positive predictive value (PPV) of 83.3%. Random Forest identified FN1 and COL3A1 as the best predictors. Rebuilding the leave-one-out cross-validated regression model improved the classification performance with a PPV of 93.3%. An independent cohort was used for classifier validation (n = 36), achieving a PPV of 88.2%. In a multivariate analysis, the two-protein classifier proved to be the only independent predictor of response. CONCLUSION: We developed a two-protein immunohistochemical classifier that performs well at predicting the non-response to neoadjuvant treatment in rectal cancer.

A randomized, open-label, phase 2 study of everolimus in combination with pasireotide LAR or everolimus alone in advanced, well-differentiated, progressive pancreatic neuroendocrine tumors: COOPERATE-2 trial.

Background: Several studies have demonstrated the antitumor activity of first-generation somatostatin analogs (SSAs), primarily targeting somatostatin receptor (sstr) subtypes 2 and 5, in neuroendocrine tumors (NET). Pasireotide, a second-generation SSA, targets multiple sstr subtypes. We compared the efficacy and safety of pasireotide plus everolimus to everolimus alone in patients with advanced, well-differentiated, progressive pancreatic NET. Patients and methods: Patients were randomized 1 : 1 to receive a combination of everolimus (10 mg/day, orally) and pasireotide long-acting release (60 mg/28 days, intramuscularly) or everolimus alone (10 mg/day, orally); stratified by prior SSA use, and baseline serum chromogranin A and neuron-specific enolase. The primary end point was progression-free survival (PFS). Secondary end points included overall survival, objective response rate, disease control rate, and safety. Biomarker response was evaluated in an exploratory analysis. Results: Of 160 patients enrolled, 79 were randomized to the combination arm and 81 to the everolimus arm. Baseline demographics and disease characteristics were similar between the treatment arms. No significant difference was observed in PFS: 16.8 months in combination arm versus 16.6 months in everolimus arm (hazard ratio, 0.99; 95% confidence interval, 0.64-1.54). Partial responses were observed in 20.3% versus 6.2% of patients in combination arm versus everolimus arm; however, overall disease control rate was similar (77.2% versus 82.7%, respectively). No significant improvement was observed in median overall survival. Adverse events were consistent with the known safety profile of both the drugs; grade 3 or 4 fasting hyperglycemia was seen in 37% versus 11% of patients, respectively. Conclusions: The addition of pasireotide to everolimus was not associated with the improvement in PFS compared with everolimus alone in this study. Further studies to delineate mechanisms by which SSAs slow tumor growth in NET are warranted.

Concordance of blood- and tumor-based detection of RAS mutations to guide anti-EGFR therapy in metastatic colorectal cancer.

BACKGROUND: Circulating tumor DNA (ctDNA) is a potential source for tumor genome analysis. We explored the concordance between the mutational status of RAS in tumor tissue and ctDNA in metastatic colorectal cancer (mCRC) patients to establish eligibility for anti-epidermal growth factor receptor (EGFR) therapy. PATIENTS AND METHODS: A prospective-retrospective cohort study was carried out. Tumor tissue from 146 mCRC patients was tested for RAS status with standard of care (SoC) PCR techniques, and Digital PCR (BEAMing) was used both in plasma and tumor tissue. RESULTS: ctDNA BEAMing RAS testing showed 89.7% agreement with SoC (Kappa index 0.80; 95% CI 0.71 - 0.90) and BEAMing in tissue showed 90.9% agreement with SoC (Kappa index 0.83; 95% CI 0.74 - 0.92). Fifteen cases (10.3%) showed discordant tissue-plasma results. ctDNA analysis identified nine cases of low frequency RAS mutations that were not detected in tissue, possibly due to technical sensitivity or heterogeneity. In six cases, RAS mutations were not detected in plasma, potentially explained by low tumor burden or ctDNA shedding. Prediction of treatment benefit in patients receiving anti-EGFR plus irinotecan in second- or third-line was equivalent if tested with SoC PCR and ctDNA. Forty-eight percent of the patients showed mutant allele fractions in plasma below 1%. CONCLUSIONS: Plasma RAS determination showed high overall agreement and captured a mCRC population responsive to anti-EGFR therapy with the same predictive level as SoC tissue testing. The feasibility and practicality of ctDNA analysis may translate into an alternative tool for anti-EGFR treatment selection.

[Breastfeeding, gross motor development and obesity, is there any causal association?] / Lactancia materna, desarrollo motor y obesidad, ¿Existe asociación causal?

Childhood obesity is the main nutritional and public health problem in Chile, being the principal causes, the increase in energy dense foods and the decline of physical activity. Interventions to prevent obesity at infancy are focused mainly in improving quality and quantity of dietary intake, without taking into account physical activity, which is expressed under two years of age, mainly by motor development. Some studies have proven that motor development at early age, may influence the ability to perform physical activity. Thus, infants scoring a lower motor development may have a greater risk of becoming obese. It isn’t know if childhood obesity causes lower motor development (given that children may have greater difficulty to move), or on the contrary, it is the lower ability to move, which increases the obesity risk. The objective of this manuscriptis analize the evidence regards the relation between breastfeeding, motor development and obesity in the childhood.To be able to understand this asocation and casual mecanism, it is important to develop stategys focused in early infancy to promote breastfeeding, healthy eating and early stimulation, starting in pediatric office.

ESMO consensus guidelines for the management of patients with metastatic colorectal cancer.

Colorectal cancer (CRC) is one of the most common malignancies in Western countries. Over the last 20 years, and the last decade in particular, the clinical outcome for patients with metastatic CRC (mCRC) has improved greatly due not only to an increase in the number of patients being referred for and undergoing surgical resection of their localised metastatic disease but also to a more strategic approach to the delivery of systemic therapy and an expansion in the use of ablative techniques. This reflects the increase in the number of patients that are being managed within a multidisciplinary team environment and specialist cancer centres, and the emergence over the same time period not only of improved imaging techniques but also prognostic and predictive molecular markers. Treatment decisions for patients with mCRC must be evidence-based. Thus, these ESMO consensus guidelines have been developed based on the current available evidence to provide a series of evidence-based recommendations to assist in the treatment and management of patients with mCRC in this rapidly evolving treatment setting.

Pancreatic NETs: where do we stand now?

The systemic management of patients with pancreatic neuroendocrine tumors includes chemotherapy and targeted agents such as everolimus and sunitinib. Which treatment to favor in a particular patient is not known. The most commonly used chemotherapy agents are streptozocin and temozolamide, often prescribed in combination with fluoropyrimidines. A potential biomarker for selection of temozolomide-based chemotherapy is O-6-methylguanine-DNA-methyltrasferase expression. Chemotherapy yields higher response rates and may be preferable in patients with higher-grade tumors and those who are symptomatic. The mammalian target of rapamycin inhibitor everolimus has shown improvement in progression-free survival (PFS) in a robust, well-conducted phase III study. Everolimus, however, can induce limiting toxicities that may result in treatment discontinuation and does not improve survival. However, the objective response rate is very low. Sunitinib, likewise, increases PFS but the data comes from a smaller trial which was terminated early. Sunitinib displays a different toxicity profile and is associated with a trend towards improved overall survival. It is clear that biomarkers to properly select the most effective agents in an individual patient are needed.