Molecular determinants of clinical outcomes with pembrolizumab versus paclitaxel in a randomized, open-label, phase III trial in patients with gastroesophageal adenocarcinoma.

BACKGROUND: In the phase III KEYNOTE-061 trial (NCT02370498), pembrolizumab did not significantly improve overall survival versus paclitaxel as second-line therapy for gastric/gastroesophageal junction (GEJ) adenocarcinoma with programmed death-ligand 1 (PD-L1) combined positive score (CPS) ≥1 tumors. The association of tissue tumor mutational burden (tTMB) status and clinical outcomes was determined, including the relationship with CPS and microsatellite instability-high (MSI-H) status. PATIENTS AND METHODS: In patients with whole exome sequencing (WES) data [420/592 (71%); pembrolizumab, 218; paclitaxel, 202], the association of tTMB with objective response rate (ORR; logistic regression), progression-free survival (PFS; Cox proportional hazards regression), and overall survival (OS; Cox proportional hazards regression) were measured using one-sided (pembrolizumab) and two-sided [paclitaxel] P values. tTMB was also evaluated using FoundationOne®CDx [205/592 (35%)]. Prespecified equivalent cut-offs of 175 mut/exome for WES and 10 mut/Mb for FoundationOne®CDx were used. RESULTS: WES-tTMB was significantly associated with ORR, PFS, and OS in pembrolizumab-treated (all P < 0.001) but not paclitaxel-treated patients (all P > 0.6) in univariate analysis. The area under the receiver operating characteristics curve for WES-tTMB and response was 0.68 [95% confidence interval (CI) 0.56-0.81] for pembrolizumab and 0.51 (95% CI 0.39-0.63) for paclitaxel in univariate analysis. There was low correlation between WES-tTMB and CPS in both treatment groups (r ≤ 0.16). WES-tTMB remained significantly associated with all clinical endpoints with pembrolizumab after adjusting for CPS and with PFS and OS after excluding known MSI-H tumors (n = 26). FoundationOne®CDx-tTMB demonstrated a positive association with ORR, PFS, and OS in pembrolizumab-treated patients (all P ≤ 0.003) but not PFS or OS in paclitaxel-treated patients (P > 0.1). CONCLUSION: This exploratory analysis from KEYNOTE-061 is the first to demonstrate a strong association between tTMB and efficacy with pembrolizumab but not paclitaxel in patients with gastric/GEJ adenocarcinoma in a randomized setting. Data further suggest tTMB is a significant and independent predictor beyond PD-L1 status.

Seroconversion and Abundance of IgG Antibodies against S1-RBD of SARS-CoV-2 and Neutralizing Activity in the Chilean Population.

COVID-19 is a pandemic caused by SARS-CoV-2. In Chile, half a million people have been infected and more than 16,000 have died from COVID-19. As part of the clinical trial NCT04384588, we quantified IgG against S1-RBD of SARS-CoV-2 (anti-RBD) in recovered people in Santiago and evaluated their suitability as COVID-19 convalescent plasma donors. ELISA and a luminescent SARS-CoV-2 pseudotype were used for IgG and neutralizing antibody quantification. 72.9% of the convalescent population (468 of 639) showed seroconversion (5-55 µg/mL anti-RBD IgG) and were suitable candidates for plasma donation. Analysis by gender, age, and days after symptom offset did not show significant differences. Neutralizing activity correlated with an increased concentration of anti-RBD IgG (p < 0.0001) and showed a high variability between donors. We confirmed that the majority of the Chilean patients have developed anti-SARS-CoV-2 antibodies. The quantification of anti-RBD IgG in convalescent plasma donors is necessary to increase the detection of neutralizing antibodies.

Access to innovative medicines for metastatic melanoma worldwide: Melanoma World Society and European Association of Dermato-oncology survey in 34 countries.

According to data from recent studies from Europe, a large percentage of patients have restricted access to innovative medicines for metastatic melanoma. Melanoma World Society and European Association of Dermato-oncology conducted a Web-based survey on access to first-line recommended treatments for metastatic melanoma by current guidelines (National Comprehensive Center Network, European Society for Medical Oncology [ESMO] and European Organization for Research and Treatment of Cancer/European Association of Dermato-oncology/European dermatology Forum) among melanoma experts from 27 European countries, USA, China, Australia, Argentina, Brazil, Chile and Mexico from September 1st, 2017 to July 1st, 2018. Data on licencing and reimbursement of medicines and the number of patient treated were correlated with the data on health expenditure per capita (HEPC), Mackenbach score of health policy performance, health technology assessment (HTA), ASCO and ESMO Magnitude of clinical benefit scale (ESMO MCBS) scores of clinical benefit and market price of medicines. Regression analysis for evaluation of correlation between the parameters was carried out using SPSS software. The estimated number of patients without access in surveyed countries was 13768. The recommended BRAFi + MEKi combination and anti-PD1 immunotherapy were fully reimbursed/covered in 19 of 34 (55.8%) and 17 of 34 (50%) countries, and combination anti-CTLA4+anti-PD1 in was fully covered in 6 of 34 (17.6%) countries. Median delay in reimbursement was 991 days, and it was in significant correlation with ESMO MCBS (p = 0.02), median market price (p = 0.001), HEPC and Mackenbach scores (p < 0.01). Price negotiations or managed entry agreements (MEAs) with national authorities were necessary for reimbursement. In conclusion, great discrepancy exists in metastatic melanoma treatment globally. Access to innovative medicines is in correlation with economic parameters as well as with healthcare system performance parameters. Patient-oriented drug development, market access and reimbursement pathways must be urgently found.

Primary and metastatic brain cancer genomics and emerging biomarkers for immunomodulatory cancer treatment.

Recent studies with immunomodulatory agents targeting both cytotoxic T-lymphocyte protein 4 (CTLA4) and programmed cell death 1 (PD1)/programmed cell death ligand 1 (PDL1) have shown to be very effective in several cancers revealing an unexpected great activity in patients with both primary and metastatic brain tumors. Combining anti-CTLA4 and anti-PD1 agents as upfront systemic therapy has revealed to further increase the clinical benefit observed with single agent, even at cost of higher toxicity. Since the brain is an immunological specialized area it's crucial to establish the specific composition of the brain tumors' microenvironment in order to predict the potential activity of immunomodulatory agents. This review briefly summarizes the basis of the brain immunogenicity, providing the most updated clinical evidences in terms of immune-checkpoint inhibitors efficacy and toxicity in both primary and metastatic brain tumors with the final aim of defining potential biomarkers for immunomodulatory cancer treatment.

Colecistectomía videolaparoscópica en el paciente geriátrico / Videolaparoscopic cholecystectomy in geriatric patient

Se presenta la experiencia del equipo quirúrgico en colecistectomía videolaparoscópica, en una serie prospectiva de 48 pacientes de ambos sexos, de 60 o mas años de edad, operados entre marzo y julio del año 2003, en el Departamento y Servicio de Cirugía del Hospital Barros Luco Trudeau; analizando la patología médica asociada, presente en el 70,83 por ciento de los pacientes; los hallazgos más relevantes del estudio ecotomográfico preoperatorio (97,91 por ciento de los pacientes); las cifras de conversión a cirugía laparotómica (14,57 por ciento) y los resultados en términos de morbilidad (8,33 por ciento) y mortalidad (0 por ciento).