Tumor Budding en cáncer rectal. Relación entre la densidad de los brotes tumorales y otros factores pronósticos / Budding tumor in rectal cancer. Relationship between tumor outbreak density and other prognostic factors

Introducción: El budding tumor (BT) es la presencia de células tumorales aisladas o en pequeños grupos situadas en el frente de invasión del tumor. Su hallazgo en alto grado es un factor de mal pronóstico independiente del cáncer colorrectal. El objetivo de este trabajo es determinar si el grado de BT está asociado con otros factores pronósticos del cáncer rectal. Material y métodos: Se incluyen las resecciones oncológicas de recto en el período 2013-2017. Los casos se agruparon según la densidad en la formación de los BT en 3 grupos, los de grado bajo, intermedio y alto. Se utilizó como valor estadístico el cálculo del odds ratio (OR). Resultados: Se analizaron las piezas de resección de 27 pacientes (15 mujeres y 12 hombres) con una media de edad de 68,4 años (40-86). Se calculó el OR para invasión ganglionar, vascular y recidiva en función del grado de budding tumoral. Discusión: Se observó una tendencia a la presencia de factores histológicos de mal pronóstico en relación al budding de alto grado, si bien el bajo número de casos no permitió demostrarlo en este estudio. Conclusiones: El análisis del grado de tumor budding es reproducible y podría ayudar a identificar pacientes con cáncer rectal de peor pronóstico. (AU)

Introduction: Tumor budding (BT) is defined as isolated or small groups of neoplastic cells located at the invasive front of the tumor. High-grade BT is a poor prognostic factor in colorectal cancer. Objective: To determine if the degree of BT is associated with other prognostic factors in rectal cancer. Materials and methods: Rectal oncological resections during the 2013-2017 period were included. Cases were stratified according to the density in the formation of BT in 3 groups: low, intermediate and high. The calculation of the odds ratio (OR) was used as a statistical value. Results: The resection specimens of 27 patients (15 women and 12 men) with a mean age of 68.4 years (40-86) were analyzed. OR for node metastases, vascular invasion and relapse was calculated according to tumor budding grade. Discussion: High-grade tumor budding seems to associate with the presence of poor prognostic factors. However, it was not possible to demonstrate it because of the small sample size. Conclusions: Tumor budding is a reproducible marker and could help to identify rectal cancer patients with a worse prognosis. (AU)

Genetic diversity and DNA content of three South American and three Eurasiatic Trifolium species

Six species of Trifolium (T. polymorphum Poir., T. riograndense Burkart, T. argentinense Speg., T. medium L., T. pratense L. and T. repens L.) were analyzed using inter-simple sequence repeats (ISSR) markers. Six selected primers generated 186 polymerase chain reaction (PCR) products exploring 112 loci in 34 genotypes analyzed with molecular sizes ranging from 200 to 1300 bp. These primers were able to discriminate among and within species, with the PCR products being on average 41.6 percent species-specific and 59.9 percent polymorphic at the within species level. Nuclear DNA content was determined by flow cytometry and revealed variation among species. The 1Cx genome size values were calculated and were found to range from 0.46 pg (T. pratense) to 0.96 pg (T. polymorphum). Genome size values of South American species were higher than those of Eurasiatic origin. The analyses of the molecular data grouped the six species in agreement with their geographical origin and clearly differentiate T. polymorphum from T. argentinense. The Eurasiatic group showed the highest average of species-specific bands (45.3 percent) and the South American group exhibited the highest amount of total bands (59.7). The highest level of intra-species polymorphisms was detected in T. argentinense (92.9 percent), followed by T. medium (89.5 percent).