The Feline calicivirus capsid protein VP1 is a client of the molecular chaperone Hsp90.

Feline calicivirus (FCV) icosahedral viral capsids are composed of dozens of structural subunits that rely on cellular chaperones to self-assemble in an orderly fashion. Here, we report that the heat shock protein 90 (Hsp90) inhibition significantly reduced FCV particle production, suggesting a role in the replicative cycle. We found that Hsp90 inhibition was not related to the synthesis or stability of the early proteins that translate from the gRNA nor to the minor capsid protein VP2 but with a reduction in the major capsid protein VP1 levels, both translated late in infection from the subgenomic RNAs. Reduction in VP1 levels was observed despite an augment of the leader of the capsid (LC)-VP1 precursor levels, from which the LC and VP1 proteins are produced after proteolytic processing by NS6/7. The direct interaction of VP1 with Hsp90 was observed in infected cells. These results suggest that upon release from the polyprotein precursor, VP1 becomes a client of Hsp90 and that this interaction is required for an efficient FCV replicative cycle.

Beyond tobacco: genomic disparities in lung cancer between smokers and never-smokers.

BACKGROUND: Tobacco use is one of the main risk factors for Lung Cancer (LC) development. However, about 10-20% of those diagnosed with the disease are never-smokers. For Non-Small Cell Lung Cancer (NSCLC) there are clear differences in both the clinical presentation and the tumor genomic profiles between smokers and never-smokers. For example, the Lung Adenocarcinoma (LUAD) histological subtype in never-smokers is predominately found in young women of European, North American, and Asian descent. While the clinical presentation and tumor genomic profiles of smokers have been widely examined, never-smokers are usually underrepresented, especially those of a Latin American (LA) background. In this work, we characterize, for the first time, the difference in the genomic profiles between smokers and never-smokers LC patients from Chile. METHODS: We conduct a comparison by smoking status in the frequencies of genomic alterations (GAs) including somatic mutations and structural variants (fusions) in a total of 10 clinically relevant genes, including the eight most common actionable genes for LC (EGFR, KRAS, ALK, MET, BRAF, RET, ERBB2, and ROS1) and two established driver genes for malignancies other than LC (PIK3CA and MAP2K1). Study participants were grouped as either smokers (current and former, n = 473) or never-smokers (n = 200) according to self-report tobacco use at enrollment. RESULTS: Our findings indicate a higher overall GA frequency for never-smokers compared to smokers (58 vs. 45.7, p-value < 0.01) with the genes EGFR, KRAS, and PIK3CA displaying the highest prevalence while ERBB2, RET, and ROS1 the lowest. Never-smokers present higher frequencies in seven out of the 10 genes; however, smokers harbor a more complex genomic profile. The clearest differences between groups are seen for EGFR (15.6 vs. 21.5, p-value: < 0.01), PIK3CA (6.8 vs 9.5) and ALK (3.2 vs 7.5) in favor of never-smokers, and KRAS (16.3 vs. 11.5) and MAP2K1 (6.6 vs. 3.5) in favor of smokers. Alterations in these genes are comprised almost exclusively by somatic mutations in EGFR and mainly by fusions in ALK, and only by mutations in PIK3CA, KRAS and MAP2K1. CONCLUSIONS: We found clear differences in the genomic landscape by smoking status in LUAD patients from Chile, with potential implications for clinical management in these limited-resource settings.

The Feline calicivirus Leader of the Capsid (LC) Protein Contains a Putative Transmembrane Domain, Binds to the Cytoplasmic Membrane, and Exogenously Permeates Cells.

Feline calicivirus (FCV), an important model for studying the biology of the Caliciviridae family, encodes the leader of the capsid (LC) protein, a viral factor known to induce apoptosis when expressed in a virus-free system. Our research has shown that the FCV LC protein forms disulfide bond-dependent homo-oligomers and exhibits intrinsic toxicity; however, it lacked a polybasic region and a transmembrane domain (TMD); thus, it was initially classified as a non-classical viroporin. The unique nature of the FCV LC protein, with no similarity to other proteins beyond the Vesivirus genus, has posed challenges for bioinformatic analysis reliant on sequence similarity. In this study, we continued characterizing the LC protein using the AlphaFold 2 and the recently released AlphaFold 3 artificial intelligence tools to predict the LC protein tertiary structure. We compared it to other molecular modeling algorithms, such as I-Tasser's QUARK, offering new insights into its putative TMD. Through exogenous interaction, we found that the recombinant LC protein associates with the CrFK plasmatic membrane and can permeate cell membranes in a disulfide bond-independent manner, suggesting that this interaction might occur through a TMD. Additionally, we examined its potential to activate the intrinsic apoptosis pathway in murine and human ovarian cancer cell lines, overexpressing survivin, an anti-apoptotic protein. All these results enhance our understanding of the LC protein's mechanism of action and suggest its role as a class-I viroporin.

Efficacy and safety of withholding antimicrobial therapy in children with cancer, fever, and neutropenia, with a demonstrated viral respiratory infection: a randomized clinical trial.

OBJECTIVES: To validate the efficacy and safety of withholding antimicrobial therapy in a new cohort of children with cancer and febrile neutropenia (FN) having a demonstrated viral respiratory tract infection. METHODS: Prospective, multicenter, noninferiority, randomized study, approved by the ethical committee, in children presenting with FN at seven hospitals in Chile, evaluated at admission for diagnosis of bacterial and viral pathogens. Children who were positive for a respiratory virus, negative for a bacterial pathogen, and had a favourable evolution after 48-72 hours of antimicrobial therapy were randomized to either maintain or withhold antimicrobial therapy. The primary endpoint was the percentage of episodes with an uneventful resolution, whereas the secondary endpoints were days of fever, days of hospitalization, requirement of antimicrobial treatment readministration, sepsis, paediatric intensive care unit admission, and death. RESULTS: A total of 301 of 939 children with FN episodes recruited between March 2021 and December 2023 had a respiratory virus as a unique identified microorganism, of which 139 had a favourable evolution at 48-72 hours and were randomized, 70 to maintain and 69 to withdraw antimicrobial therapy. The median days of antimicrobial therapy was 5 (IQR 3-6) versus 3 (IQR 3-6) days (p < 0.001), with similar frequency of uneventful resolution 66/70 (94%) and 66/69 (96%); relative risk, 1.01; (95% CI, 0.93 to 1.09), absolute risk difference 0.01; (95% CI, -0.05 to 0.08) and similar number of days of fever and days of hospitalization. No cases of sepsis, paediatric intensive care unit admission, or death were reported. DISCUSSION: We validated the strategy of withdrawal antimicrobial therapy in children with FN and viral respiratory tract infection based on clinical and microbiological/molecular diagnostic criteria. This will enable advances in antimicrobial stewardship strategies with a possible future impact on antimicrobial resistance.

High linoleic acid levels in red blood cells predict a poor response to neoadjuvant chemotherapy in human epidermal growth factor receptor type 2-positive breast cancer patients.

OBJECTIVE: Polyunsaturated fatty acids are categorized as ω-3 or ⍵-6. Previous studies demonstrate that breast cancers display a high expression of fatty acid synthase and high fatty acid levels. Our study sought to determine if changes in plasma or red blood cell membrane fatty acid levels were associated with the response to preoperative (neoadjuvant) chemotherapy in non-metastatic breast cancer patients. METHODS: Our prospective study assessed fatty acid levels in plasma and red blood cell membrane. Response to neoadjuvant chemotherapy was evaluated by the presence or absence of pathologic complete response and/or residual cancer burden. RESULTS: A total of 28 patients were included. First, patients who achieved pathologic complete response had significantly higher neutrophil-to-lymphocyte ratio versus no pathologic complete response (P = 0.003). Second, total red blood cell membrane polyunsaturated fatty acids were higher in the absence of pathologic complete response (P = 0.0028). Third, total red blood cell membrane ⍵-6 polyunsaturated fatty acids were also higher in no pathologic complete response (P < 0.01). Among ⍵-6 polyunsaturated fatty acids, red blood cell membrane linoleic acid was higher in the absence of pathologic complete response (P < 0.01). Notably, plasma polyunsaturated fatty acid, ⍵-6, and linoleic acid levels did not have significant differences. A multivariate analysis confirmed red blood cell membrane linoleic acid was associated with no pathologic complete response; this was further confirmed by receiver operating characteristic analysis (specificity = 92.3%, sensitivity = 76.9%, and area under the curve = 0.855). CONCLUSIONS: Pending further validation, red blood cell membrane linoleic acid might serve as a predictor biomarker of poorer response to neoadjuvant chemotherapy in non-metastatic human epidermal growth factor receptor type 2-positive breast cancer. Measuring fatty acids in red blood cell membrane could offer a convenient, minimally invasive strategy to identifying patients more likely to respond or those with chemoresistance.

Outcome of Infants Born to Women with Chronic Hepatitis B: A Local Risk-Based Strategy in a Low Prevalence Country.

BACKGROUND: Chronic hepatitis-B virus (HBV) infection due to mother-to-child transmission (MTCT) during the perinatal period is an important global health concern. Chile is a low-prevalence country with an increasing migratory inflow from Latin- American countries, with intermediate to high endemic rates of HBV infection, and until 2021, there is no universal maternal screening. This study aimed to evaluate infant outcomes using a risk-based strategy of maternal screening to prevent MTCT of hepatitis B virus (HBV) in a low-prevalence country. METHODS: This prospective study included infants born to HBsAg-positive women detected using a local risk-based strategy. The exposed infants received immunoprophylaxis (IP) and follow-up to evaluate their clinical outcomes and immune responses through post-serological vaccine testing (PSVT) after completing the three- dose schedule of the HBV vaccine. RESULTS: A total of 99 HBsAg-positive mothers were detected. Seventy-six (82%) infants completed the follow-up and had PSVT between 9 and 12 months of age. 55.2% female, the median gestational age was 39 weeks (25-41) and the median birth weight was 3,130g (816-4,400 g). All patients received IP with recombinant HBV vaccine plus hepatitis-B virus immunoglobulin (HBIG) and three doses of the HBV vaccine. There were no cases of HBV infection, and 96% (72) responded to immunization with HBsAg antibodies (anti-HBsAg) >10 UI/ml, with a median level of 799 IU/ml. CONCLUSIONS: A high-risk strategy can be implemented in countries with non-universal screening for VHB. Timely IP plus high-uptake VHB vaccination in infants born to HBsAg-positive mothers was associated with a high immunogenic response and absence of MTCT.

Suboptimal use of ovarian function suppression in very young women with early breast cancer: a real-world data study.

PURPOSE: The incidence of breast cancer in young women (BCYW) has increased in recent decades. Malignant disease in this subset is characterized by its aggressiveness and poor prognosis. Ovarian function suppression (OFS) in these patients improves survival especially in hormone receptor-positive (HR +) cases. The Regan Composite Risk (RCR) is a prognostic tool to identify high-risk HR + BC candidates for OFS. Our study sought to characterize a Chilean cohort of early HR + BCYW assessing the use of OFS and its related prognosis and the utility of RCR in our patients. METHODS: This was a retrospective population cohort study that included ≤ 35-year-old early HR + /human epidermal growth factor receptor 2 -negative (HER2-) BC patients treated between 2001 and 2021. Analysis included clinical-pathological characteristics, treatment strategies, and survival. Also, we evaluated the association between RCR and survival. RESULTS: A total of 143 patients were included into our study, representing 2.9% of all early BC cases in our registry. Median age was 31 years old (range: 19-35). Most patients (93%) received endocrine therapy (ET). Of these, 18% received OFS. No survival differences were observed among treatment strategies. Median RCR score for patients treated with CT plus ET was significantly higher vs. ET alone (2.95 vs. 1.91; p = 0.0001). Conversely, patients treated with tamoxifen alone had significantly lower RCR scores vs. OFS (2.72 vs. 3.14; p = 0.04). Higher RCR scores were associated with poorer overall survival. CONCLUSION: Less than 20% of very young women with early HR + /HER2-BC in our cohort received OFS, in most cases, this involved surgical oophorectomy. RCR score was higher in patients that underwent CT and OFS and was associated with survival, regardless of treatment. We confirm the RCR score as a valuable prognostic tool to identify high-risk BC patients who could benefit from OFS.

Usefulness of Peripheral Blood Cultures in Children With Cancer and Episodes of Fever and Neutropenia.

BACKGROUND: The collection of blood cultures (BC) is key for guiding antimicrobial therapy in children with febrile neutropenia (FN), more than 90% have central venous catheters (CVC). There is no consensus on the need for peripheral BC over central BC in this population. The aim of this study was to determine the contribution of peripheral BC over central BC in the diagnosis of bloodstream infections in children with FN. METHODS: Descriptive, retrospective study, episodes of FN recorded prospectively in 6 hospitals in Santiago, Chile, from 2016 to 2021. Central and peripheral BC were drawn upon admission. All episodes with at least one (+) BC were allocated to one of these groups: consistent (+) BC, inconsistent (+) BC, only CVC (+) BC and only peripheral (+) BC. The volume of the samples was recorded. RESULTS: The analysis included 241 episodes of FN with at least one (+) BC. The median age was 7.2 years, 51% were female, 84% had hematological cancer and 98% had episodes of high-risk FN. Of a total of 241 episodes, 135 (56%) had consistent (+) BC, 13 (5%) had inconsistent (+) BC, 35 (15%) had only CVC (+) BC and 58 (24%) had only peripheral (+) BC. There were no significant differences in the volume of the samples between central and peripheral BC. CONCLUSIONS: The proportion of bloodstream infections detected only through peripheral BC was 24%, higher than previously reported, not due to sample volume. We recommend obtaining peripheral as well CVC BC in children with FN.

Upper-Limb Disability and the Severity of Lymphedema Reduce the Quality of Life of Patients with Breast Cancer-Related Lymphedema.

Breast cancer-related lymphedema (BCRL) is characterized by arm swelling, pain, and discomfort, reducing the quality of life (QoL) of affected individuals. BRCL is caused via the blockage or disruption of the lymphatic vessels following cancer treatments, leading to an accumulation of fluid in the affected arm. While current BCRL rehabilitation treatments seek to reduce arm swelling, our study aimed to examine the impact of both the magnitude of lymphedema (ΔVolume) and arm disability on three dimensions of QoL: social, physical, and psychological. Using the Disabilities of the Arm, Shoulder, and Hand questionnaire (DASH) and the Upper Limb Lymphedema 27 questionnaire (ULL) in a group of 30 patients, we found that the magnitude of lymphedema (ΔVolume) was associated with the social dimension of QoL (r = 0.37, p = 0.041), but not with other dimensions. On the other hand, arm disability was associated with all evaluated dimensions of QoL (social, physical, and psychological: p < 0.001, p = 0.019, and p = 0.050 (borderline), respectively). These findings suggest that BCRL rehabilitation strategies should not only aim to reduce the magnitude of lymphedema but should also seek to improve or preserve arm functionality to enhance the QoL of BCRL patients.

Access disparities and underutilization of germline genetic testing in Chilean breast cancer patients.

PURPOSE: Latin American reports on genetic cancer risk assessments are scarce. In Chile, current breast cancer (BC) guidelines do not define strategies for germline genetic testing. Our study sought to quantify the disparities in access to genetic testing in Chilean BC patients, according to international standards and their clinical characteristics to explore improvement strategies. METHODS: Retrospective analysis of invasive BC databases including patients treated in a Public Hospital (PH) and in an Academic Private Center (AC) in Santiago, Chile between 2012 and 2021. RESULTS: Of 5438 BC patients, 3955 had enough data for National Comprehensive Cancer Network (NCCN) categorization. From these, 1911 (48.3%) fulfilled NCCN criteria for germline testing, of whom, 300 were tested for germline mutations and 268 with multigene panels. A total of 65 pathogenic variants were found in this subset. As expected, BRCA1/2 mutations were the most frequent (17.7%). Access to genetic testing was higher in AC versus PH (19.6% vs. 10.3%, p = 0.0001). Other variables associated with germline genetic testing were BC diagnosis after 2018, being 45 years old or younger at diagnosis, BC family history (FH), FH of ovarian cancer, non-metastatic disease, and triple-negative subtype. CONCLUSION: In our cohort, 15% of BC patients who met NCCN criteria for germline testing were effectively tested. This percentage was even lower at the PH. Current recommendations encourage universal genetic testing for BC patients; however, our findings suggest that Chile is far from reaching such a goal and national guidelines in this regard are urgently needed. To our knowledge, this is the first study of its kind in Chile and Latin America.

Body Composition and Metabolic Dysfunction Really Matter for the Achievement of Better Outcomes in High-Grade Serous Ovarian Cancer.

Although obesity-associated metabolic disorders have a negative impact on various cancers, such evidence remains controversial for ovarian cancer. Here, we aimed to evaluate the impact of body composition (BC) and metabolism disorders on outcomes in high-grade serous ovarian cancer (HGSOC). METHODS: We analyzed clinical/genomic data from two cohorts (PUC n = 123/TCGA-OV n = 415). BC was estimated using the measurement of adiposity/muscle mass by a CT scan. A list of 425 genes linked to obesity/lipid metabolism was used to cluster patients using non-negative matrix factorization. Differential expression, gene set enrichment analyses, and Ecotyper were performed. Survival curves and Cox-regression models were also built-up. RESULTS: We identified four BC types and two clusters that, unlike BMI, effectively correlate with survival. High adiposity and sarcopenia were associated with worse outcomes. We also found that recovery of a normal BC and drug interventions to correct metabolism disorders had a positive impact on outcomes. Additionally, we showed that immune-cell-depleted microenvironments predominate in HGSOC, which was more evident among the BC types and the obesity/lipid metabolism cluster with worse prognosis. CONCLUSIONS: We have demonstrated the relevance of BC and metabolism disorders as determinants of outcomes in HGSOC. We have shone a spotlight on the relevance of incorporating corrective measures addressing these disorders to obtain better results.

Clinical Outcome in Children With Cancer With Two or More Microorganisms Isolated From Blood Cultures During Episodes of Fever and Neutropenia.

BACKGROUND: Bacterial bloodstream infections are a major cause of morbidity and mortality in children with cancer and episodes of fever and neutropenia (FN). The aim of this study was to evaluate the clinical outcome in children with cancer with 2 or more microorganisms isolated from blood cultures during their episodes of FN. METHODS: Between 2016 and 2021, children presenting with high-risk FN, admitted to any of the 6 participating hospitals in Santiago, Chile, were included in this study if they have positive blood cultures. We compared the clinical outcome of children with 2 or more microorganisms versus those with single agent isolation. RESULTS: A total of 1074 episodes of high-risk FN were enrolled in the study period, of which 27% (298) had positive blood cultures and 3% (32) had 2 or more microorganisms isolated from blood cultures. The most frequent identified agents were Viridans group streptococci and Escherichia coli in 20%, followed by Coagulase negative staphylococci in 14%. Children with 2 or more microorganisms presented more days of fever (7 vs. 4 days, P = 0.02), needed longer courses of antimicrobial therapy (16 vs. 14 days, P = 0.04) and had higher mortality at day 30 (13% vs. 1%, P = 0.003). CONCLUSIONS: Children with cancer and FN with 2 or more microorganisms isolated from blood cultures had a worse clinical outcome than children with single agent isolation.

Palbociclib in advanced stage hormone receptor-positive breast cancer: real-world data from a Chilean multicentre registry.

Background: The addition of cyclin-dependent kinases inhibitors (CDKi) to endocrine therapy (ET) as the first- or second line treatment improves progression-free and overall survival (OS) in hormone receptor-positive, HER2 negative (HR+/HER2-) advanced stage breast cancer (ABC). Our study compared survival rates and prognostic factors in Chilean patients that used palbociclib as first or subsequent (≥second) lines of treatment in a real-world setting. Methods: Our retrospective population-cohort study included HR+/HER2- ABC patients. We calculated 5-year OS and performed a multivariate analysis to determine prognostic factors. Results: A total of 106 patients were included. Median age was 49 years (19-86), 28.3% (30) had de novo stage IV disease; 63% received palbociclib with ET as first line, 54% of them with aromatase inhibitor over fulvestrant. Median OS for the entire cohort was 99 months and 5-year OS was 69%. Patients that received first line palbociclib had a 5-year OS of 89% versus 43% for ET monotherapy or ≥second line palbociclib (p = 0.0062). Multivariate analysis showed that the year at diagnosis and CDKi timing (first line versus ≥second line) were significantly associated with OS. Conclusion: Our real-world data show that first-line CDKi + ET provides a statistically significant benefit in OS versus ≥second line in HR+/HER2- ABC patients.

[Voriconazole monitorization in pediatric patients, difficulties in dose adjustment]. / Importancia de la monitorización de concentraciones plasmáticas de voriconazol y dificultad en ajuste de dosis en un paciente pediátrico.

We present a 10-year-old male patient with a diagnosis of relapsed acute myeloid leukemia (AML), presenting with high-risk febrile neutropenia (HRFN), after a cycle of intensive chemotherapy, evolving with an invasive fungal infection demonstrated by histopathology. Treatment with intravenous voriconazole was started, with erratic plasmatic levels, which require successive dose adjustments which also occurred with oral administration. Finally, he had a favorable response to treatment, despite of the dosing difficulties to reach therapeutic levels. Active search as well as preemptive antifungal therapy, together with plasmatic level monitorization of voriconazole allowed a prompt recovery and improved the patient prognosis.

Importancia de la monitorización de concentraciones plasmáticas de voriconazol y dificultad en ajuste de dosis en un paciente pediátrico / Voriconazole monitorization in pediatric patients, difficulties in dose adjustment

Resumen Presentamos el caso de un escolar de 10 años, con el diagnóstico de una recaída de una leucemia mieloide aguda que cursó con un episodio de una neutropenia febril de alto riesgo, posterior a un ciclo intensivo de quimioterapia, evolucionando con una infección fúngica invasora demostrada por histopatología. Se inició tratamiento con voriconazol intravenoso, evolucionando con concentraciones plasmáticas erráticas que requirieron sucesivos ajustes de dosis, lo que también ocurrió con la administración oral del medicamento. Finalmente, tuvo una respuesta favorable al tratamiento, a pesar de la dificultad de la dosificación para alcanzar niveles terapéuticos. La búsqueda activa y la terapia antifúngica anticipada, así como la monitorización seriada de concentraciones terapéuticas de voriconazol, permitieron un tratamiento antifúngico óptimo y oportuno, mejorando el pronóstico del paciente.

Abstract We present a 10-year-old male patient with a diagnosis of relapsed acute myeloid leukemia (AML), presenting with high-risk febrile neutropenia (HRFN), after a cycle of intensive chemotherapy, evolving with an invasive fungal infection demonstrated by histopathology. Treatment with intravenous voriconazole was started, with erratic plasmatic levels, which require successive dose adjustments which also occurred with oral administration. Finally, he had a favorable response to treatment, despite of the dosing difficulties to reach therapeutic levels. Active search as well as preemptive antifungal therapy, together with plasmatic level monitorization of voriconazole allowed a prompt recovery and improved the patient prognosis.

Validation of an NGS Panel Designed for Detection of Actionable Mutations in Tumors Common in Latin America.

Next-generation sequencing (NGS) is progressively being used in clinical practice. However, several barriers preclude using this technology for precision oncology in most Latin American countries. To overcome some of these barriers, we have designed a 25-gene panel that contains predictive biomarkers for most current and near-future available therapies in Chile and Latin America. Library preparation was optimized to account for low DNA integrity observed in formalin-fixed paraffin-embedded tissue. The workflow includes an automated bioinformatic pipeline that accounts for the underrepresentation of Latin Americans in genome databases. The panel detected small insertions, deletions, and single nucleotide variants down to allelic frequencies of 0.05 with high sensitivity, specificity, and reproducibility. The workflow was validated in 272 clinical samples from several solid tumor types, including gallbladder (GBC). More than 50 biomarkers were detected in these samples, mainly in BRCA1/2, KRAS, and PIK3CA genes. In GBC, biomarkers for PARP, EGFR, PIK3CA, mTOR, and Hedgehog signaling inhibitors were found. Thus, this small NGS panel is an accurate and sensitive method that may constitute a more cost-efficient alternative to multiple non-NGS assays and costly, large NGS panels. This kind of streamlined assay with automated bioinformatics analysis may facilitate the implementation of precision medicine in Latin America.

Oncological resection, myasthenia gravis and staging as prognostic factors in thymic tumours: a Chilean case series.

BACKGROUND: Thymic epithelial tumours are rare and highly heterogeneous. Reports from the United States suggest an overall incidence of 0.15 per 100,000/year. In contrast, the incidence of these tumours in Latin America is largely unknown and reports are scarce, somewhat limited to case reports. METHODS: Herein, we report a series of 38 thymic tumours from a single institution, retrospectively incorporated into this study. Patient characteristics and outcomes including age, sex, stage, paraneoplastic syndromes, treatment regimens and the date of decease were obtained from medical records. RESULTS: Most cases in our series were females and young age (<50 years old) and early stage by Masaoka-Koga or the Moran staging systems. Also, a 34% of patients had myasthenia gravis (MG). Next, we analysed overall survival rates in our series and found that the quality of surgery (R0, R1 or R2), MG status and staging (Masaoka-Koga, Moran or TNM) were prognostic factors. Finally, we compared our data to larger thymic tumour series. CONCLUSIONS: Overall, our study confirms complete surgical resection as the standard, most effective treatment for thymic epithelial tumours. Also, the Masaoka-Koga staging system remains as a reliable prognostic factor but also the Moran staging system should be considered for thymomas.

Pathological complete response to neoadjuvant chemotherapy, but not the addition of carboplatin, is associated with improved survival in Chilean triple negative breast cancer patients: a report of real world data.

BACKGROUND: Breast cancer (BC) is the leading cause of cancer death for Chilean women. About 11% of cases are triple-negative (TN) BC. These are characterised by poor prognosis, higher risk of early recurrence and visceral dissemination versus other BC subtypes. Current standard treatment for early-stage non-metastatic TNBC patients consists of neoadjuvant chemotherapy (NACT) followed by surgery and radiotherapy. Pathological complete response (pCR) to NACT is associated with an increase in survival rates. In general, NACT and adjuvant regimens involve similar cytotoxic drugs. Recent studies have postulated that the use of platinum compounds in TNBC would increase response rates. However, their effects on patient survival remain uncertain. MATERIALS AND METHODS: We retrieved and analysed medical records from a total of 156 Chilean stage I-III TNBC female patients that received NACT and compared survival rates using carboplatin (Cb)-containing versus non-Cb-containing regimens at two health cancer centres. RESULTS: Median age was 51 years (range: 24-81); 13.5% (n = 21) received Cb-containing regimens, 80.1% (n = 125) received sequential anthracyclines plus taxanes; 29.5% (n = 46) of the total group achieved pCR, 28% for the standard treatment and 35% (n = 8) for the Cb-containing group (p = 0.59). We confirmed pCR was associated with prolonged overall survival, invasive and distant disease-free survival (Log-rank p = 0.0236). But the addition of Cb was not associated with differences in survival measures (Log-rank p = 0.5216). CONCLUSIONS: To the best of authors' knowledge, this is the first report on real-world data in the Chilean population assessing the effect of Cb-containing NACT in TNBC. The authors' results suggest no survival benefit by the addition of Cb to standard NACT. However, we confirm an increase in survival associated to pCR regardless of treatment.

A Molecular Stratification of Chilean Gastric Cancer Patients with Potential Clinical Applicability.

Gastric cancer (GC) is a complex and heterogeneous disease. In recent decades, The Cancer Genome Atlas (TCGA) and the Asian Cancer Research Group (ACRG) defined GC molecular subtypes. Unfortunately, these systems require high-cost and complex techniques and consequently their impact in the clinic has remained limited. Additionally, most of these studies are based on European, Asian, or North American GC cohorts. Herein, we report a molecular classification of Chilean GC patients into five subtypes, based on immunohistochemical (IHC) and in situ hybridization (ISH) methods. These were Epstein-Barr virus positive (EBV+), mismatch repair-deficient (MMR-D), epithelial to mesenchymal transition (EMT)-like, and accumulated (p53+) or undetected p53 (p53-). Given its lower costs this system has the potential for clinical applicability. Our results confirm relevant molecular alterations previously reported by TCGA and ACRG. We confirm EBV+ and MMR-D patients had the best prognosis and could be candidates for immunotherapy. Conversely, EMT-like displayed the poorest prognosis; our data suggest FGFR2 or KRAS could serve as potential actionable targets for these patients. Finally, we propose a low-cost step-by-step stratification system for GC patients. To the best of our knowledge, this is the first Latin American report on a molecular classification for GC. Pending further validation, this stratification system could be implemented into the routine clinic.

First-line endocrine therapy for advanced breast cancer. A real-world study at a Latin American university health institution.

Objective: Clinical guidelines recommend the use of endocrine therapy (ET) in advanced hormone receptor positive (HR+) human epidermal growth factor receptor type 2 negative (HER2-) breast cancer (BC) patients in the absence of visceral disease or ET resistance. Furthermore, studies indicate similar response and survival rates using ET or cytotoxic chemotherapy (CT).Methods: Herein, we assessed clinical characteristics, type of systemic therapy and survival rates of advanced HR + HER2-BC patients in our database.Results: A total of 172 advanced HR + HER2-BC patients were treated at our institution between 1997 and 2019. Sixty percent received first-line ET (4% received combined ET). Median age of this subset was 55 years (range: 30-86). Similarly, the median age of patients that received CT was 54 years (range: 21-83). Over time, 30% of patients received ET in the 2000-2005 period; this increased to 70% in the 2016-2019 period (p = .045). Overall survival (OS) was 97 months and 51 months for patients treated with ET or CT, respectively (p = .002).Conclusions: To the best of our knowledge this is the first study assessing the use of ET in Chilean advanced HR + HER2-BC patients. Several patients in our institution receive CT without indication. The increase in ET usage over time can be attributed to better and faster immunohistochemical detection methods for Estrogen Receptor (ER), changes in educational and government policies, and a wider variety of ET options. Finally, clinical trials have failed to demonstrate a substantial benefit of CT over ET in this setting.