Estudio de variantes genéticas en 169 pacientes de cáncer de pulmón no microcítico / Study of genetic variants in 169 non-small cell lung cancer patients

Introducción: El cáncer de pulmón es la principal causa de muerte por cáncer en nuestro país. El cáncer de pulmón de células no pequeñas (CPCNP) representa el paradigma de la medicina personalizada. El objetivo principal de este trabajo es estudiar la frecuencia en nuestro medio de las variantes clínicamente significativas más frecuentemente descritas en CPCNP. Material y métodos: Se estudia la expresión inmunohistoquímica de TTF1, p40 y PD-L1 y la frecuencia de variantes genéticas mediante secuenciación masiva (NGS) con un panel de 52 genes, en 174 muestras incluidas en parafina de CPNCP en 169 pacientes (111 hombres y 52 mujeres) de la provincia de Cádiz. Resultados: La expresión inmunohistoquímica de TTF1, p40 y PD-L1 fue positiva en el 87%, el 0% y el 46% de los adenocarcinomas y en el 0%, el 100% y el 41% de los carcinomas escamosos. En NGS, las variantes de un solo nucleótido (SNV) más frecuentes fueron KRAS (36%), EGFR (14%), BRAF (10%), PIK3CA (8%) y MET (3%). Las variantes en el número de copias (CNV) más frecuentes fueron las amplificaciones en NF1 (30%), EGFR (18%), CCND1 (9%), MYC (9%) y KRAS (7%). En mujeres, las SNV en EGFR fueron más frecuentes que en hombres (p<0,0001). El adenocarcinoma es el tipo histológico más frecuente con SNV en KRAS (p=0,007361) o en EGFR (p<0,0001). En 16 pacientes (9,47%) se detectaron fusiones génicas, 9 casos en el gen MET. Conclusiones: Detectamos nuevas asociaciones entre expresión inmunohistoquímica y algunas variantes génicas, que podrían tener impacto en el tratamiento de pacientes de CPNCP.(AU)

Introduction: Lung cancer is the leading cause of cancer death in our country. Non-small cell lung cancer (NSCLC) represents the paradigm of personalized medicine. The main objective of this study is analysing the distribution of the most frequently described clinically significant variants in NSCLC, in our environment. Material and methods: We studied the immunohistochemical expression of TTF1, p40 and PD-L1 and the genetic variants frequency using Next-Generation Sequencing (NGS) with a panel of 52 genes, in 174 NSCLC paraffin-embedded samples in 169 patients (111 men and 52 women) from the province of Cádiz. Results: The immunohistochemical expression of TTF1, p40 and PD-L1 was positive in 87%, 0% and 46% in adenocarcinoma, and 0%, 100% and 41% in squamous cell carcinoma. In NGS, the most common single nucleotide variants (SNVs) were KRAS (36%), EGFR (14%), BRAF (10%), PIK3CA (8%), and MET (3%). The most frequent copy number variants (CNVs) were amplifications in NF1 (30%), EGFR (18%), CCND1 (9%), MYC (9%) and KRAS (7%). In women, SNV in EGFR are more frequent than in men (P<.0001). Adenocarcinoma is the most frequent histological type with SNV in KRAS (P=.007361) or in EGFR (P<.0001). Gene fusions were detected in 16 patients (9.47%), in 9 cases in the MET gene. Conclusions: We detected associations, not described so far, between immunohistochemical expression and specific gene variants, which could have an impact on the treatment of NSCLC patients.(AU)

Clinical, Histopathologic and Genetic Features of Rhabdoid Meningiomas.

Rhabdoid meningiomas (RM) shows heterogeneous histological findings, and a wide variety of chromosomal copy number alterations (CNA) are associated with an unpredictable course of the disease. In this study, we analyzed a series of 305 RM samples from patients previously reported in the literature and 33 samples from 23 patients studied in our laboratory. Monosomy 22-involving the minimal but most common recurrent region loss of the 22q11.23 chromosomal region was the most observed chromosomal alteration, followed by losses of chromosomes 14, 1, 6, and 19, polysomies of chromosomes 17, 1q, and 20, and gains of 13q14.2, 10p13, and 21q21.2 chromosomal regions. Based on their CNA profile, RM could be classified into two genetic subgroups with distinct clinicopathologic features characterized by the presence of (1) chromosomal losses only and (2) combined losses and gains of several chromosomes. The latter displays a higher frequency of WHO grade 3 tumors and poorer clinical outcomes.