Isolated Oligohydramnios at Term as an Indication for Labor Induction: A Systematic Review and Meta-Analysis.

Objective: To investigate whether isolated oligohydramnios at term is associated with increased rates of perinatal morbidity and mortality and whether induction of labor in term pregnancies with isolated oligohydramnios is superior to conservative management in reducing perinatal morbidity and mortality.

Study Design: We searched databases from inception to May 2015. We included studies that evaluated isolated oligohydramnios at term and perinatal outcome.

Variation in KRAS driver substitution distributions between tumor types is determined by both mutation and natural selection.

Different tumor types vary greatly in their distribution of driver substitutions. Here, we analyzed how mutation and natural selection contribute to differences in the distribution of KRAS driver substitutions between lung, colon and pancreatic adenocarcinomas. We were able to demonstrate that both differences in mutation and differences in selection drive variation in the distribution of KRAS driver substitutions between tumor types.

Intratumor Heterogeneity of KRAS Mutation Status in Pancreatic Ductal Adenocarcinoma Is Associated With Smaller Lesions.

Objectives: Recent studies have demonstrated intratumor heterogeneity (ITH) for genetic mutations in various tumors and suggest that ITH might have significant clinical impact. Because KRAS is the most commonly mutated oncogene in pancreatic ductal adenocarcinoma and has an important role in pancreatic carcinogenesis, the purpose of this study was to evaluate ITH for KRAS gene mutation and its clinical significance.

Methods: Deep sequencing of 47 pancreatic ductal adenocarcinoma cases was used to determine the fraction of KRAS mutant alleles.