Histopathological, Clinical, And Molecular (HICAM) score for patients with colorectal liver metastases.

BACKGROUND: Histopathological and molecular features have been proposed to hold prognostic information, but few have been validated. The aim of this retrospective study was to validate the Genetic And Morphological Evaluation ('GAME') score and assess the impact of histological characteristics on the prognosis in patients with colorectal liver metastases. METHODS: Data were collected from 176 patients with metastatic colorectal cancer undergoing liver resection at Hospital de la Santa Creu i Sant Pau. Patients were classified into Genetic And Morphological Evaluation score groups and relapse-free survival and overall survival were calculated. Histopathological changes in colorectal liver metastases were documented and prognostic variables were selected to create a post-surgery score, called the Histopathological, Clinical, And Molecular ('HICAM') score. RESULTS: Regarding the Genetic And Morphological Evaluation score, the high-risk group had a median relapse-free survival of 8.8 months, compared with 20.5 months for the low-risk group (P = 0.005), and the high-risk group had a median overall survival of 37.8 months, compared with 67.0 months for the low-risk group (P = 0.005). Histological examination of 144 liver samples showed that the desertic immune phenotype was associated with worse overall survival in the multivariable analysis (P = 0.020). The Histopathological, Clinical, And Molecular score variables were age at diagnosis, tumour burden score, carcinoembryonic antigen levels greater than or equal to 20 ng/ml, primary tumour resection, TNM stage at diagnosis, molecular status, histopathological growth patterns, and immune phenotypes of the liver. The high-risk group had a median relapse-free survival of 8.4 months, compared with 20.4 months for the low-risk group (P < 0.001), and a median overall survival of 30.4 months, compared with 105.0 months for the low-risk group (P < 0.001). CONCLUSION: The Genetic And Morphological Evaluation score was validated as a preoperative prognostic tool to predict candidacy for liver resection. The Histopathological, Clinical, And Molecular score could be useful to assess adjuvant treatment after hepatic resection.

Local and systemic replicative fitness for viruses in specialist, generalist, and non-specialist interactions with salmonid hosts.

Host tissues represent diverse resources or barriers for pathogen replicative fitness. We tested whether viruses in specialist, generalist, and non-specialist interactions replicate differently in local entry tissue (fin), and systemic target tissue (kidney) using infectious hematopoietic necrosis virus (IHNV) and three salmonid fish hosts. Virus tissue replication was host specific, but one feature was shared by specialists and the generalist which was uncommon in the non-specialist interactions: high host entry and replication capacity in the local tissue after contact. Moreover, specialists showed increased replication in systemic target tissues early after host contact. By comparing ancestral and derived IHNV viruses, we also characterized replication tradeoffs associated with specialist and generalist evolution. Compared with the ancestral virus, a derived specialist gained early local replicative fitness in the new host but lost replicative fitness in the ancestral host. By contrast, a derived generalist showed small replication losses relative to the ancestral virus in the ancestral host but increased early replication in the local tissue of novel hosts. This study shows that the mechanisms of specialism and generalism are host specific and that local and systemic replication can contribute differently to overall within host replicative fitness for specialist and generalist viruses.

Medical oncology workload, workforce census, and needs in Spain: two nationwide studies by the Spanish Society of medical oncology.

PURPOSE: Growing complexity and demand for cancer care entail increased challenges for Medical Oncology (MO). The Spanish Society of Medical Oncology (SEOM) has promoted studies to provide updated data to estimate the need for medical oncologists in 2040 and to analyse current professional standing of young medical oncologists. METHODS: Two national, online surveys were conducted. The first (2021) targeted 146 Heads of MO Departments, and the second (2022), 775 young medical oncologists who had completed their MO residency between 2014 and 2021. Participants were contacted individually, and data were processed anonymously. RESULTS: Participation rates reached 78.8% and 48.8%, respectively. The updated data suggest that 87-110 new medical oncologist full-time equivalents (FTEs) should be recruited each year to achieve an optimal ratio of 110-130 new cases per medical oncologist FTE by 2040. The professional standing analysis reveals that 9.1% of medical oncologists trained in Spain do not work in clinical care in the country, with tremendous employment instability (only 15.2% have a permanent contract). A high percentage of young medical oncologists have contemplated career paths other than clinical care (64.5%) or working in other countries (51.7%). CONCLUSIONS: Optimal ratios of medical oncologists must be achieved to tackle the evolution of MO workloads and challenges in comprehensive cancer care. However, the incorporation and permanence of medical oncologists in the national healthcare system in Spain could be compromised by their current sub-optimal professional standing.

Real-world study on microsatellite instability and mismatch repair deficiency testing patterns among patients with metastatic colorectal cancer in Spain.

PURPOSE: Clinical practice guidelines recommend that all patients with metastatic colorectal cancer (mCRC) should be tested for mismatch repair deficiency (dMMR) or microsatellite instability-high (MSI-H). We aimed to describe the dMMR/MSI-H testing practice in patients with mCRC in Spanish centers. METHODS: Multicenter, observational retrospective study that included patients newly diagnosed with mCRC or who progressed to a metastatic stage from early/localized stages. RESULTS: Three hundred patients were included in the study from May 2020 through May 2021, with a median age of 68 years, and two hundred twenty-five (75%) had stage IV disease at initial diagnosis; two hundred eighty-four patients received first-line treatment, and dMMR/MSI-H testing was performed in two hundred fifty-one (84%) patients. The results of the dMMR/MSI-H tests were available in 61 (24%) of 251 patients before the diagnosis of metastatic disease and in 191 (81%) of 236 evaluable patients for this outcome before the initiation of first-line treatment. Among the 244 patients who were tested for dMMR/MSI-H with IHC or PCR, 14 (6%) were MMR deficient. The most frequent type of first-line treatment was the combination of chemotherapy and biological agent, that was received by 71% and 50% of patients with MMR proficient and deficient tumors, respectively, followed by chemotherapy alone, received in over 20% of patients in each subgroup. Only 29% of dMMR/MSI-H tumors received first-line immunotherapy. CONCLUSION: Our study suggests that a high proportion of patients with mCRC are currently tested for dMMR/MSI-H in tertiary hospitals across Spain. However, there is still room for improvement until universal testing is achieved. TRIAL REGISTRATION: Not applicable.

Coproduction and modeling spatial contact networks prevent bias about infectious hematopoietic necrosis virus transmission for Snake River Basin salmonids.

Much remains unknown about variation in pathogen transmission across the geographic range of a free-ranging fish or animal species and about the influence of movement (associated with husbandry practices or animal behavior) on pathogen transmission. Salmonid hatcheries are an ideal system in which to study these processes. Salmonid hatcheries are managed for endangered species recovery, supplementation of threatened or at-risk fish stocks, support of fisheries, and ecosystem stability. Infectious hematopoietic necrosis virus (IHNV) is a rhabdovirus of significant concern to salmon aquaculture. Landscape IHNV transmission dynamics previously had been estimated only for salmonid hatcheries in the Lower Columbia River Basin (LCRB). The objectives of this study were to estimate IHNV transmission dynamics in a unique geographic region, the Snake River Basin (SRB), and to quantitatively estimate the effect of model coproduction on inference because previous assessments of coproduction have been qualitative. In contrast to the LCRB, the SRB has hatchery complexes consisting of a main hatchery and ≥1 satellite facility. Knowledge about hatchery complexes was held by a subset of project researchers but would not have been available to project modelers without coproduction. Project modelers generated and tested multiple versions of Bayesian susceptible-exposedinfected models to realistically represent the SRB and estimate the effect of coproduction. Models estimated the frequency of transmission routes, route-specific infection probabilities, and infection probabilities for combinations of salmonid hosts and IHNV lineages. Model results indicated that in the SRB, avoiding exposure to IHNV-positive adult salmonids is the most important action to prevent juvenile infections. Migrating adult salmonids exposed juvenile cohort-sites most frequently, and the infection probability was greatest following exposure to migrating adults. Without coproduction, the frequency of exposure by migrating adults would have been overestimated by 70 cohort-sites, and the infection probability following exposure to migrating adults would have been underestimated by∼0.09. The coproduced model had less uncertainty in the infection probability if no transmission route could be identified (Bayesian credible interval (BCI) width = 0.12) compared to the model without coproduction (BCI width = 0.34). Evidence for virus lineage MD specialization on steelhead and rainbow trout (both Oncorhynchus mykiss) was apparent without model coproduction. In the SRB, we found a greater probability of virus lineage UC infection in Chinook salmon (Oncorhynchus tshawytscha) compared to in O. mykiss, whereas in the LCRB, UC more clearly exhibited a generalist approach. Coproduction influenced estimates that depended on transmission routes, which operated differently at main hatcheries and satellite sites within hatchery complexes. Hatchery complexes are found outside of the SRB and are not specific to salmonid hatcheries alone. There is great potential for coproduction and modeling spatial contact networks to advance understanding about infectious disease transmission in complex production systems and surrounding free-ranging animal populations.

Current professional standing of young medical oncologists in Spain: a nationwide survey by the Spanish Society of Medical Oncology + MIR section.

BACKGROUND: There is a lack of knowledge about the career paths and employment situation of young medical oncologists. The aim of our study was to evaluate the current professional standing of these professionals in Spain. METHODS: The Spanish Society of Medical Oncology + MIR section conducted a national online survey in May 2021 of young medical oncology consultants (< 6 years of expertise) and final year medical oncology residents. RESULTS: A total of 162 responses were eligible for analysis and included participants from 16 autonomous communities; 64% were women, 80% were consultants, and 20% were residents. More than half of the participants performed routine healthcare activity and only 7% research activity. Almost three quarters (73%) were subspecialized in a main area of interest and almost half of these chose this area because it was the only option available after residency. Half of the respondents (51%) considered working abroad and 81% believed the professional standing in Spain was worse than in other countries. After finishing their residency, only 22 were offered a job at their training hospital. Just 16% of participants had a permanent employment contract and 87% were concerned (score of ≥ 5 on a scale of 1-10) about their job stability. In addition, one quarter of the participants in our study showed an interest in increasing their research activity. CONCLUSIONS: The choice of subspecialty in medical oncology may depend on job opportunities after residency rather than personal interest. The abundance of temporary contracts may have influenced the job stability concerns observed. Future mentoring strategies should engage in building a long-term career path for young medical oncologists.

Liquid Biopsy Detects Early Molecular Response and Predicts Benefit to First-Line Chemotherapy plus Cetuximab in Metastatic Colorectal Cancer: PLATFORM-B Study.

PURPOSE: Chemotherapy plus anti-EGFR is standard first-line therapy in RAS wild-type (wt) metastatic colorectal cancer (mCRC), but biomarkers of early response are clinically needed. We aimed to define the utility of ctDNA to assess early response in patients with mCRC receiving first-line anti-EGFR therapy. EXPERIMENTAL DESIGN: Prospective multicentric study of tissue patients with RAS wt mCRC treated with first-line chemotherapy plus cetuximab undergoing sequential liquid biopsies. Baseline and early (C3) ctDNA were analyzed by NGS. Trunk mutations were assessed as surrogate marker of total tumor burden. RAS/BRAF/MEK/EGFR-ECD were considered mutations of resistance. ctDNA results were correlated with clinical outcome. RESULTS: One hundred patients were included. ctDNA was detected in 72% of patients at baseline and 34% at C3. Decrease in ctDNA trunk mutations correlated with progression-free survival (PFS; HR, 0.23; P = 0.001). RAS/BRAF were the only resistant mutations detected at C3. An increase in the relative fraction of RAS/BRAF at C3 was followed by an expansion of the RAS clone until PD, and was associated with shorter PFS (HR, 10.5; P < 0.001). The best predictor of response was the combined analysis of trunk and resistant mutations at C3. Accordingly, patients with "early molecular response" (decrease in trunk and decrease in resistant mutations) had better response (77.5% vs. 25%, P = 0.008) and longer PFS (HR, 0.18; P < 0.001) compared with patients with "early molecular progression" (increase in trunk and/or increase in resistant mutations). CONCLUSIONS: ctDNA detects early molecular response and predicts benefit to chemotherapy plus cetuximab. A comprehensive NGS-based approach is recommended to integrate information on total disease burden and resistant mutations. See related commentary by Eluri et al., p. 302.

Variation in within-host replication kinetics among virus genotypes provides evidence of specialist and generalist infection strategies across three salmonid host species.

Theory of the evolution of pathogen specialization suggests that a specialist pathogen gains high fitness in one host, but this comes with fitness loss in other hosts. By contrast, a generalist pathogen does not achieve high fitness in any host, but gains ecological fitness by exploiting different hosts, and has higher fitness than specialists in nonspecialized hosts. As a result, specialist pathogens are predicted to have greater variation in fitness across hosts, and generalists would have lower fitness variation across hosts. We test these hypotheses by measuring pathogen replicative fitness as within-host viral loads from the onset of infection to the beginning of virus clearance, using the rhabdovirus infectious hematopoietic necrosis virus (IHNV) in salmonid fish. Based on field prevalence and virulence studies, the IHNV subgroups UP, MD, and L are specialists, causing infection and mortality in sockeye salmon, steelhead, and Chinook salmon juveniles, respectively. The UC subgroup evolved naturally from a UP ancestor and is a generalist infecting all three host species but without causing severe disease. We show that the specialist subgroups had the highest peak and mean viral loads in the hosts in which they are specialized, and they had low viral loads in nonspecialized hosts, resulting in large variation in viral load across hosts. Viral kinetics show that the mechanisms of specialization involve the ability to both maximize early virus replication and avoid clearance at later times, with different mechanisms of specialization evident in different host-virus combinations. Additional nuances in the data included different fitness levels for nonspecialist interactions, reflecting different trade-offs for specialist viruses in other hosts. The generalist UC subgroup reached intermediate viral loads in all hosts and showed the smallest variation in fitness across hosts. The evolution of the UC generalist from an ancestral UP sockeye specialist was associated with fitness increases in steelhead and Chinook salmon, but only slight decreases in fitness in sockeye salmon, consistent with low- or no-cost generalism. Our results support major elements of the specialist-generalist theory, providing evidence of a specialist-generalist continuum in a vertebrate pathogen. These results also quantify within-host replicative fitness trade-offs resulting from the natural evolution of specialist and generalist virus lineages in multi-host ecosystems.

Randomized phase II trial of FOLFIRI-panitumumab compared with FOLFIRI alone in patients with RAS wild-type circulating tumor DNA metastatic colorectal cancer beyond progression to first-line FOLFOX-panitumumab: the BEYOND study (GEMCAD 17-01).

PURPOSE: Panitumumab plus FOLFOX (P-FOLFOX) is standard first-line treatment for RAS wild-type (WT) metastatic colorectal cancer. The value of panitumumab rechallenge is currently unknown. We assessed addition of panitumumab to FOLFIRI (P-FOLFIRI) beyond progression to P-FOLFOX in patients with no RAS mutations in liquid biopsy (LB). METHODS: In this randomized phase II trial, patients were assigned (3:2 ratio) to second-line P-FOLFIRI (arm A) or FOLFIRI alone (arm B). LB for circulating tumor DNA analysis was collected at study entry and at disease progression. Primary endpoint was 6-month progression-free survival. Two-stage Simon design required 85 patients to be included (EudraCT 2017-004519-38). RESULTS: Between February 2019 and November 2020, 49 patients were screened (16 RAS mutations in LB detected) and 31 included (18 assigned to arm A and 13 to arm B). The study was prematurely closed due to inadequate recruitment. Serious adverse events were more frequent in arm A (44% vs. 23%). Overall response rate was 33% (arm A) vs. 7.7% (arm B). Six-month progression-free survival rate was 66.7% (arm A) and 38.5% (arm B). Median progression-free survival was 11.0 months (arm A) and 4.0 months (arm B) (hazard ratio, 0.58). At disease progression, RAS or BRAF mutations in LB were found in 4/11 patients (36%) in arm A and 2/10 (20%) in arm B. CONCLUSIONS: The BEYOND study suggests a meaningful benefit of P-FOLFIRI beyond progression to P-FOLFOX in metastatic colorectal cancer patients with WT RAS status selected by LB. This strategy deserves further investigation.

SEOM-GEMCAD-TTD clinical guidelines for localized rectal cancer (2021).

The management of localized rectal cancer requires a multidisciplinary approach to optimize outcomes, reduce morbidity and prevent under or overtreatments. While early stages may obtain benefit of local resections without any additional therapies, locally advanced rectal cancer becomes a challenge defining the better sequential strategy of surgery, radiotherapy and chemotherapy. The latest results of international phase III studies have positioned the total neoadjuvant therapy as a potential new standard of care in high risk rectal cancers, however, the best schedule is still not well defined.

Elucidating the role of pharmacogenetics in irinotecan efficacy and adverse events in metastatic colorectal cancer patients.

INTRODUCTION: Irinotecan is a cytotoxic agent that is widely used in the treatment of several types of solid tumors. However, although it is generally well tolerated, approximately 20% to 35% of patients develop severe toxicity, particularly delayed-type diarrhea and neutropenia. As the incidence of such toxicities is often associated with the UGT1A1 *28/*28, *6/*28 and *6/*6 genotypes, individualized dosing could reduce these adverse events. Furthermore, prospective trials have shown that patients harboring the UGT1A1 *1/*1 and *1/*28 genotypes can tolerate higher doses of irinotecan, which may in turn impact on a better outcome. Upfront UGT1A1 genotyping could therefore be a usefulness strategy in order to individualize irinotecan dosing, but consensus on the recommended dose based on the UGT1A1 genotype is still lacking. AREAS COVERED: This review summarizes the results of the main pharmacogenetic studies focused on irinotecan. We provide an overview of current evidence and recommendations for individualized dosing of irinotecan in metastatic colorectal cancer patients. EXPERT OPINION: Implementation of UGT1A1*28 and UGT1A1*6 genotyping in clinical practice is a first step toward personalizing irinotecan therapy. This approach is likely to improve patient care and reduce healthcare costs. Future large and prospective studies will help to clarify the clinical value of other genetic markers in irinotecan treatment personalization.

Temperature Variation and Host Immunity Regulate Viral Persistence in a Salmonid Host.

Environmental variation has important effects on host-pathogen interactions, affecting large-scale ecological processes such as the severity and frequency of epidemics. However, less is known about how the environment interacts with host immunity to modulate virus fitness within hosts. Here, we studied the interaction between host immune responses and water temperature on the long-term persistence of a model vertebrate virus, infectious hematopoietic necrosis virus (IHNV) in steelhead trout (Oncorhynchus mykiss). We first used cell culture methods to factor out strong host immune responses, allowing us to test the effect of temperature on viral replication. We found that 15 ∘C water temperature accelerated IHNV replication compared to the colder 10 and 8 ∘C temperatures. We then conducted in vivo experiments to quantify the effect of 6, 10, and 15 ∘C water temperatures on IHNV persistence over 8 months. Fish held at 15 and 10 ∘C were found to have higher prevalence of neutralizing antibodies compared to fish held at 6 ∘C. We found that IHNV persisted for a shorter time at warmer temperatures and resulted in an overall lower fish mortality compared to colder temperatures. These results support the hypothesis that temperature and host immune responses interact to modulate virus persistence within hosts. When immune responses were minimized (i.e., in vitro) virus replication was higher at warmer temperatures. However, with a full potential for host immune responses (i.e., in vivo experiments) longer virus persistence and higher long-term virulence was favored in colder temperatures. We also found that the viral RNA that persisted at later time points (179 and 270 days post-exposure) was mostly localized in the kidney and spleen tissues. These tissues are composed of hematopoietic cells that are favored targets of the virus. By partitioning the effect of temperature on host and pathogen responses, our results help to better understand environmental drivers of host-pathogen interactions within hosts, providing insights into potential host-pathogen responses to climate change.

Frequency and clinical relevance of DPYD genetic variants in gastrointestinal cancer patients.

OBJECTIVE: To determine the prevalence of loss-of-function variants in the dihydropyrimidine dehydrogenase gene in patients with gastrointestinal neoplasms, assess their clinical relevance, and evaluate the  implementation of a multidisciplinary circuit at three months from its  implementation. METHOD: This is a descriptive, observational and retrospective study, which  included adult patients with gastrointestinal cancer treated at a tertiary  university hospital who underwent dihydropyrimidine dehydrogenase genotyping between September 2019 and December 2020. The  variables collected were sex, age, type of cancer, location, stage, treatment received, indication of treatment and degree of toxicity  developed during the first three cycles. The genotyped variants were  rs3918290 (c.1905+1G>A), rs55886062 (c.1679T>G), rs67376798  (c.2846A>T) and rs75017182 (c.1129-5923C>G). RESULTS: A total of 115 patients were included. The frequency of heterozygous dihydropyrimidine dehydrogenase variant carriers was 9.6% (11  patients). The most frequently identified variant was rs75017182 (6 patients). The second most common variant was rs67376798 (3 patients),  followed by rs3918290 (2 patients). No patients presented with the  rs55886062 variant. Two of the dihydropyrimidine dehydrogenase carriers  developed  grade 3-5 toxicity after the first cycle of a regimen that included  fluoropyrimidines. Both received full doses of fluoropyrimidine, since their  dihydropyrimidine dehydrogenase genotype was unknown before treatment  initiation. None of the dihydropyrimidine dehydrogenase carriers who began treatment with a reduced dose of fluoropyrimidine experienced grade 3-5  toxicity. Since the creation in October 2020 of a multidisciplinary team, with  the active participation of hospital pharmacists, the monthly average of dihydropyrimidine dehydrogenase genotyping studies has increased from 6.4  (January-October) to 17.5 (November-December). CONCLUSIONS: The present study shows a relatively high prevalence of loss-of- function variants in the dihydropyrimidine dehydrogenase gene as well as the  importance of genotyping such variants before starting a treatment with  fluoropyrimidines. Hospital pharmacists can contribute to the implementation  of pharmacogenetics in daily clinical practice in a tertiary hospital.

OBJETIVO: Determinar la prevalencia de variantes de pérdida de función en el  gen de la dihidropirimidina deshidrogenasa (DPYD) en pacientes con tumores  digestivos, valorar su relevancia clínica y evaluar la implementación de un  circuito multidisciplinar tras tres meses de funcionamiento.Método: Estudio descriptivo, observacional y retrospectivo donde se incluyeron los pacientes adultos afectos de tumores digestivos, atendidos en  un hospital universitario de tercer nivel, a los que se había  afectuado el genotipado de DPYD entre septiembre de 2019 y diciembre de  2020. Las variables recogidas fueron sexo, edad, tipo de cáncer, localización,  estadio, tratamiento recibido, indicación del tratamiento y grado de toxicidad desarrollado durante los tres primeros ciclos. Se genotiparon las  variantes rs3918290 (c.1905+1G>A), rs55886062 (c.1679T>G), rs67376798 (c.2846A>T) y rs75017182 (c.1129-5923C>G). RESULTADOS: Se incluyeron 115 pacientes. La frecuencia de portadores en  heterocigosis de variantes del gen DPYD fue del 9,6% (11 pacientes). La  variante más frecuentemente identificada fue el rs75017182 (6 pacientes). La  segunda variante más frecuente fue el rs67376798 (3 pacientes), seguida del  rs3918290 (2 pacientes). Ningún paciente presentó la variante rs55886062.  Dos de los pacientes portadores desarrollaron toxicidad  grados 3-5 tras el  primer ciclo de un esquema que incluía fluoropirimidinas. Ambos recibieron  dosis plenas de fluoropirimidina, puesto que no se conocía el genotipo de DPYD antes de iniciar el tratamiento. Ninguno de los pacientes portadores que  tmpezó el tratamiento con una dosis reducida de fluoropirimidina experimentó  toxicidad grados 3-5. Desde la creación en octubre de 2020 de un equipo  multidisciplinar, con participación activa del farmacéutico hospitalario, se ha  incrementado el número de estudios de genotipado de DPYD de una media de  6,4 estudios mensuales (enero-octubre) a 17,5 (noviembre-diciembre). CONCLUSIONES: Nuestro estudio muestra la relativamente elevada prevalencia de variantes de pérdida de función en el gen DPYD, así como la  importancia de genotiparlas antes de empezar un esquema de tratamiento que  contenga fluoropirimidinas. El farmacéutico hospitalario puede contribuir a la implementación de la farmacogenética en la  práctica clínica diaria en un hospital de tercer nivel.

Infectious hematopoietic necrosis virus specialization in a multihost salmonid system.

Many pathogens interact and evolve in communities where more than one host species is present, yet our understanding of host-pathogen specialization is mostly informed by laboratory studies with single species. Managing diseases in the wild, however, requires understanding how host-pathogen specialization affects hosts in diverse communities. Juvenile salmonid mortality in hatcheries caused by infectious hematopoietic necrosis virus (IHNV) has important implications for salmonid conservation programs. Here, we evaluate evidence for IHNV specialization on three salmonid hosts and assess how this influences intra- and interspecific transmission in hatchery-reared salmonids. We expect that while more generalist viral lineages should pose an equal risk of infection across host types, viral specialization will increase intraspecific transmission. We used Bayesian models and data from 24 hatcheries in the Columbia River Basin to reconstruct the exposure history of hatcheries with two IHNV lineages, MD and UC, allowing us to estimate the probability of juvenile infection with these lineages in three salmonid host types. Our results show that lineage MD is specialized on steelhead trout and perhaps rainbow trout (both Oncorhynchus mykiss), whereas lineage UC displayed a generalist phenotype across steelhead trout, rainbow trout, and Chinook salmon. Furthermore, our results suggest the presence of specialist-generalist trade-offs because, while lineage UC had moderate probabilities of infection across host types, lineage MD had a small probability of infection in its nonadapted host type, Chinook salmon. Thus, in addition to quantifying probabilities of infection of socially and economically important salmonid hosts with different IHNV lineages, our results provide insights into the trade-offs that viral lineages incur in multihost communities. Our results suggest that knowledge of the specialist/generalist strategies of circulating viral lineages could be useful in salmonid conservation programs to control disease.

Novel Somatic Genetic Variants as Predictors of Resistance to EGFR-Targeted Therapies in Metastatic Colorectal Cancer Patients.

BACKGROUND: About 40% of RAS/BRAF wild-type metastatic colorectal cancer (mCRC) patients undergoing anti-EGFR-based therapy have poor outcomes. Treatment failure is not only associated with poorer prognosis but higher healthcare costs. Our aim was to identify novel somatic genetic variants in the primary tumor and assess their effect on anti-EGFR response. PATIENTS AND METHODS: Tumor (somatic) and blood (germline) DNA samples were obtained from two well-defined cohorts of mCRC patients, those sensitive and those resistant to EGFR blockade. Genetic variant screening of 43 EGFR-related genes was performed using targeted next-generation sequencing (NGS). Relevant clinical data were collected through chart review to assess genetic results. RESULTS: Among 61 patients, 38 were sensitive and 23 were resistant to treatment. We identified eight somatic variants that predicted non-response. Three were located in insulin-related genes (I668N and E1218K in IGF1R, T1156M in IRS2) and three in genes belonging to the LRIG family (T152T in LRIG1, S697L in LRIG2 and V812M in LRIG3). The remaining two variants were found in NRAS (G115Efs*46) and PDGFRA (T301T). We did not identify any somatic variants related to good response. CONCLUSIONS: This study provides evidence that novel somatic genetic variants along the EGFR-triggered pathway could modulate the response to anti-EGFR drugs in mCRC patients. It also highlights the influence of insulin-related genes and LRIG genes on anti-EGFR efficacy. Our findings could help characterize patients who are resistant to anti-EGFR blockade despite harboring RAS/BRAF wild-type tumors.

ABCB1 Genetic Variants as Predictors of Irinotecan-Induced Severe Gastrointestinal Toxicity in Metastatic Colorectal Cancer Patients.

Irinotecan is widely used in the treatment of metastatic colorectal cancer (mCRC) despite its severe toxicities. Toxicity is often associated with the UGT1A1*28/*28 genotype. An explanation for idiopathic toxicity beyond the UGT1A1 biomarker, however, remains a major concern for clinicians. One of the main irinotecan transporters is P-glycoprotein (P-gp), which is a hepatic efflux pump encoded by ABCB1. P-gp is involved in the biliary excretion of irinotecan and its active metabolite SN-38. We aimed to assess whether functional variants in ABCB1 also contribute to identifying patients at risk of toxicity. A cohort of 308 mCRC patients treated with irinotecan-based regimens were genotyped for polymorphisms in ABCB1 (rs1128503, rs2032582, and rs1045642). The effect of these variants and their haplotypes on irinotecan-induced severe toxicity (diarrhea, neutropenia, asthenia, nausea, and mucositis) was assessed. After adjusting for the relevant clinical and pathological parameters in the multivariate analysis, we found rs1128503 was significantly associated with severe diarrhea and mucositis (P=0.014 and P=0.002, respectively). Additionally, rs2032582 was associated with severe mucositis (P<0.001). Our results show that rs1128503 genotyping could help to predict severe gastrointestinal toxicity induced by irinotecan.

Donación y trasplante de órganos en medio de la pandemia COVID-19: Consecuencias y retos para un país emergente / Organ Donation and Transplantation in the Midst of the COVID-19 Pandemic: Consequences and Challenges for an Emerging Country

La pandemia del SARS-CoV 2 es uno de los eventos en salud pública más relevantes de los últimos años, sus efectos se han traducido en millones de casos de contagios, en más de 430.000 fallecimientos y en un aumento en la necesidad de camas de cuidados intensivos alrededor del mundo. En ese contexto, se ha presentado una reducción significativa de la actividad de donación y trasplantes en varios países, y Colombia no ha sido ajena a ese fenómeno. El presente artículo, pretende dar al lector una perspectiva del estado actual de la donación y trasplantes en el mundo y en Colombia, así como plantear algunos retos que genera la pandemia del SARS-CoV 2 para la ejecución segura del proceso de donación y trasplantes en países con recursos humanos, financieros y de infraestructura limitados.

The SARS-CoV 2 outbreak is one of the most important events of public health around the world; this disease has affected millions of people, has killed over 430.000 people and has increased the needed of intensive care unit beds around the world. During the pandemic the world has seen a decline in the organ donation and transplantation activities, Colombian transplant model has been affected too. This paper wants to show the current situation of organ donation and transplantation during SARS-CoV 2 pandemic and explore some dilemmas around organ donation and transplantation for emerging countries.

Pharmacogenetic clinical randomised phase II trial to evaluate the efficacy and safety of FOLFIRI with high-dose irinotecan (HD-FOLFIRI) in metastatic colorectal cancer patients according to their UGT1A 1 genotype.

BACKGROUND: Patients harbouring the UGT1A1*28/*28 genotype are at risk of severe toxicity with the standard irinotecan dose. However, this dose is considerably lower than the dose that can be tolerated by UGT1A1*1/*1 and *1/*28 patients. This randomised phase II trial evaluated the efficacy and safety of the FOLFIRI regimen with high-dose irinotecan (HD-FOLFIRI) in metastatic colorectal cancer patients. METHODS: Eighty-two patients with the UGT1A1*1/*1 or the *1/*28 genotype were randomised to receive HD-FOLFIRI versus FOLFIRI. Patients with the UGT1A1*28/*28 genotype were excluded. In the experimental group, the irinotecan dose was 300 mg/m2 for UGT1A1*1/*1 and 260 mg/m2 for *1/*28 patients. In the control group, the dose was 180 mg/m2. We analysed the overall response rate (ORR), toxicity, and survival. RESULTS: The ORR was significantly higher in the HD-FOLFIRI group (67.5 versus 43.6%; p = 0.001 OR: 1.73 [95% CI:1.03-2.93]). Neutropenia (17.7%), diarrhoea (5.1%), and asthenia (5.1%) were the most common grade 3-4 toxicity. No differences were observed in severe toxicity (22.5% versus 20.5%), dose reduction (22.5% versus 28.2%), or prophylactic G-CSF (17.5% versus 12.8%). No difference in survival was found. CONCLUSIONS: Patients with the UGT1A1*1/*1 and *1/*28 genotypes can receive high doses of irinotecan to achieve a more favourable ORR without significant adverse events.