Mutación del gen p53 en el cáncer de la vesícula biliar / P53 gene mutation in gallbladder cancer

Background: Gallbladder cancer frequency and mortality renders it one of the most important neoplastic diseases in Chile. P53 tumor suppressor gene has been studied in most types of cancer, but there is scarce information about it in gallbladder cancer. Aim: To study the frequency of P53 gene mutation in gallbladder cancer in the ninth region of Chile. Material and methods: In 25 pathological samples of gallbladder cancer, the direct amplification and sequencing of p53 gene exons 5,6,7,8-8 was possible. Results: Seventeen punctual mutations were observed in 13 cases (52 percent). There were 10 transitions, 5 transversions, one insertion (codon 194) and one deletion (codon 186). Eight cases had mutations in exon 5, six had mutations in exon 6, two had mutations in exon 7 and one had mutations in exons 8-9. In 14 of 25 cases, gene p53 protein was positive. When immunohistochemical expression of gene p53 protein was positive in more than 20 percent of cells, there was a high correlation between genetic alterations and immunohistochemical expression of the protein, with a specificity, sensitivity, positive and negative predictive values over 80 percent. Conclusions: P53 gene mutation is observed in a high proportion of gallbladder cancers at it can be accurately detected with conventional immunohistochemical techniques. The importance of this gene in the genesis of this carcinoma should be determined studying preneoplastic lesions and early carcinomas

Estudio bacteriológico de la bilis vesicular en un área de alto riesgo de cáncer vesicular / Microbiological study of gallbladder bile in a high risk zone for gallbladder cancer

Background: Gallbladder cancer is frequent in Chile and there is sparse information about the association between this type of cancer and the presence of bacteria in the gallbladder bile. Aim: To determine the presence of aerobic bacteria in gallbladder bile in patients with and without gallbladder cancer. Material and methods: A microbiological analysis of bile and pathological study was performed in 608 gallbladders, obtained during to cholecystectomies performed to 513 women and 95 men aged 44 years old as a mean. Results: Pathological study showed a chronic cholecystitis in 468 cases (77 percent), an acute cholecystitis in 140 (33 percent), cancer in 24 (3.9 percent) and dysplasia in 5 cases (0.8 percent). A positive culture was obtained in 22.5 percent of women and 28.5 percent of males. Twenty seven percent of women over 30 years old had positive cultures compared with 10 percent of younger women (p <0.001). Thirty two percent of acute cholecystitis had positive cultures, compared with 24 percent of chronic cholecystitis (p=0.03). E Coli was isolated in 51 percent of positive cases, streptococci-enterococci in 24 percent, enterobacter sp in 9 percent, klebsiella and proteus in lower proportions. Salmonella sp was isolated in 4 cases, being all women with chronic cholecystitis. Thirteen of 29 cases with cancer or dysplasia had positive cultures (45 percent), compared with 25 percent of patients with inflammatory gallbladder diseases (p=0.02). streptococci-enterococci were isolated in 7 cases and enterobacter sp in three. Conclusions: The presence of salmonella sp in gallbladder bile was not frequent in the studied patients. Its role in the pathogenesis of gallbladder cancer must be reassessed