PET-CT para el manejo de pacientes con cáncer testicular tipo seminoma con masa residual post quimioterapia / PET-CT for the management of testicular seminoma patients with post-chemotherapy residual masses

INTRODUCCIÓN En pacientes con cáncer testicular avanzado tipo seminoma que tienen lesiones residuales post quimioterapia de más de 3 cm, el PET-CT podría seleccionar un subgrupo susceptible de ser manejado con seguimiento, evitando una resección quirúrgica innecesaria de tumor no viable. MÉTODOS Realizamos una búsqueda en Epistemonikos, la mayor base de datos de revisiones sistemáticas en salud, la cual es mantenida mediante el cribado de múltiples fuentes de información, incluyendo MEDLINE, EMBASE, Cochrane, entre otras. Extrajimos los datos desde las revisiones identificadas, analizamos los datos de los estudios primarios, realizamos un metanálisis y preparamos una tabla de resumen de los resultados utilizando el método GRADE. RESULTADOS Y CONCLUSIONES Identificamos tres revisiones sistemáticas que en conjunto incluyeron 11 estudios primarios, de los cuales, ninguno es un ensayo aleatorizado. Concluimos que el uso de PET-CT en la evaluación de masas residuales post quimioterapia en pacientes con cáncer testicular tipo seminoma podría evitar un porcentaje importante de cirugías innecesarias (certeza de la evidencia baja). Además, el uso de PET-CT podría presentar balances riesgo/beneficio y costo/beneficio favorables en el manejo de pacientes con cáncer testicular tipo seminoma. Sin embargo, se requieren revisiones sistemáticas y estudios primarios que evalúen directamente el impacto diagnóstico del test.

INTRODUCTION The use of PET-CT could select a subgroup of advanced testicular seminoma patients that display post-chemotherapy residual masses measuring >3 cm and could be managed with surveillance, avoiding unnecessary surgical resection of unviable tumor masses. METHODS We searched in Epistemonikos, the largest database of systematic reviews in health, which is maintained by screening multiple information sources, including MEDLINE, EMBASE, Cochrane, among others. We extracted data from the systematic reviews, reanalyzed data of primary studies, conducted a meta-analysis and generated a summary of findings table using the GRADE approach. RESULTS AND CONCLUSIONS We identified three systematic reviews that included eleven primary studies; none of these were randomized trials. We concluded the assessment of postchemotherapy residual masses by PET-CT in testicular seminoma patients may prevent unnecessary surgeries, but the certainty of the evidence is low. Furthermore, PET-CT could also offer a favorable risk/benefit and cost/benefit ratio for the management of testicular seminoma patients. However, systematic reviews and primary studies assessing the direct diagnostic impact of PET-CT are required.

The haemagglutinins of influenza A (H1N1) viruses in the 'O' or 'D' phases exhibit biological and antigenic differences.

Influenza A (H1N1) viruses when initially isolated in mammalian cell cultures (MDCK cells) had different agglutination reactions with chicken and guinea-pig erythrocytes compared to the same viruses after passage. On first isolation the virus HA resembled the 'O' phase viruses described originally by Burnet and Bull and agglutinated mammalian but not avian erythrocytes. After passage, the virus HA resembled a classical 'D' phase virus and agglutinated both avian and mammalian erythrocytes. Monoclonal and polyclonal antisera detected antigenic differences between the HAs of the viruses in the 'O' and 'D' phases. The 'O' phase virus HA reacted preferentially with antibodies in post infection human antisera. Viruses in the 'O' phase replicated poorly in the allantoic cavity of embryonated hens' eggs whilst 'D' phase virus replicated in both MDCK cells and in embryonated hens' eggs. At least three distinguishable subpopulations of influenza A (H1N1) viruses may co-exist in clinical throat swab material, including viruses possessing HAs in the 'O' and 'D' phases and other 'D' phase viruses cultivable in embryonated hens' eggs but antigenically distinguishable from the corresponding 'D' phase virus in MDCK cells.

Aplastic crisis caused by B19 virus in a child during induction therapy for acute lymphoblastic leukemia.

A child undergoing induction therapy for acute lymphoblastic leukemia suffered an aplastic crisis associated with B19 virus infection. Good response to the antiblastic therapy led to a burst in erythropoiesis favoring high viral replication, which was responsible for strong erythroblastic inhibition and severe viremia. The patient's B19 antibody response became evident very late, probably because of the antiblastic effect of the therapy; nevertheless, recovery was complete in little more than a week, favored by B19 IgG transfusion with a red blood cell concentrate. This report suggests that immunosuppressed subjects, as well as those suffering from hemolytic anemia must also be considered "at risk" for aplastic crisis due to B19 infection.

Human parvovirus infection in haemophiliacs first infused with treated clotting factor concentrates.

A group of 27 first infused haemophiliacs was studied for association between heat-treated clotting factor concentrates and transmission of human parvovirus B19. The prevalence rate of B19 antibody, detected by the Immunoelectroosmophoresis (IEOP) reaction, was 55.5% in this group of first infused subjects, significantly higher than the 29.3% of the control group of 58 healthy blood donors but lower than the 93.3% of antibody positive subjects in a group of 30 haemophiliacs multitreated with unheated products. Five of 17 B19 antibody negative patients produced human parvovirus IgM, detectable by radioimmunoassay, after the first treatment with heated concentrates; two of them developed viraemia 6 and 10 days, respectively, after the first infusion dose. These results lead to the conclusion that human parvovirus is transmissible by blood derivatives even when they have been exposed to steam- or dry-heat treatment.