The role of radiotherapy in the conservative treatment of ductal carcinoma in situ of the breast.

Breast-conserving surgery (BCS) followed by radiotherapy (RT) has become the standard of care for the treatment of early-stage (St. I-II) invasive breast carcinoma. However, controversy exists regarding the value of RT in the conservative treatment of ductal carcinoma in situ (DCIS). In this article we review the role of RT in the management of DCIS. Retrospective and prospective trials and meta-analyses published between 1975 and 2007 in the MEDLINE database, and recent issues of relevant journals/handbooks relating to DCIS, BCS and RT were searched for. In retrospective series (10,194 patients) the 10-year rate of local recurrence (LR) with and without RT was reported in the range of 9-28% and 22-54%, respectively. In four large randomised controlled trials (NSABP-B-17, EORTC-10853, UKCCCR, SweDCIS; 4,568 patients) 50 Gy whole-breast RT significantly decreased the 5-year LR rate from 16-22% (annual LR rate: 2.6-5.0%) to 7-10% (annual LR rate: 1.3-1.9%). In a recent meta-analysis of randomised trials the addition of RT to BCS resulted in a 60% risk reduction of both invasive and in situ recurrences. In a multicentre retrospective study, an additional dose of 10 Gy to the tumour bed yielded a further 55% risk reduction compared to RT without boost. To date, no subgroups have been reliably identified that do not benefit from RT after BCS. In the NSABP-B-24 trial, the addition of tamoxifen (TAM) to RT reduced ipsilateral (11.1% vs. 7.7%) and contralateral (4.9% vs. 2.3%) breast events significantly. In contrast, in the UKCCCR study, TAM produced no significant reduction in all breast events. Based on available evidence obtained from retrospective and prospective trials, all patients with DCIS have potential benefit from RT after BCS. Further prospective studies are warranted to identify subgroups of low-risk patients with DCIS for whom RT can be safely omitted. Until long-term results of ongoing studies on outcomes of patients treated with BCS alone (with or without TAM or aromatase inhibitors) are available, RT should be routinely recommended after BCS for all patients except those with contraindication

Lentiviral Delivery of a Vesicular Glutamate Transporter 1 (VGLUT1)-Targeting Short Hairpin RNA Vector Into the Mouse Hippocampus Impairs Cognition

Glutamate is the principle excitatory neurotransmitter in the mammalian brain, and dysregulation of glutamatergic neurotransmission is implicated in the pathophysiology of several psychiatric and neurological diseases. This study utilized novel lentiviral short hairpin RNA (shRNA) vectors to target expression of the vesicular glutamate transporter 1 (VGLUT1) following injection into the dorsal hippocampus of adult mice, as partial reductions in VGLUT1 expression should attenuate glutamatergic signaling and similar reductions have been reported in schizophrenia. The VGLUT1-targeting vector attenuated tonic glutamate release in the dorsal hippocampus without affecting GABA, and selectively impaired novel object discrimination (NOD) and retention (but not acquisition) in the Morris water maze, without influencing contextual fear-motivated learning or causing any adverse locomotor or central immune effects. This pattern of cognitive impairment is consistent with the accumulating evidence for functional differentiation along the dorsoventral axis of the hippocampus, and supports the involvement of dorsal hippocampal glutamatergic neurotransmission in both spatial and nonspatial memory. Future use of this nonpharmacological VGLUT1 knockdown mouse model could improve our understanding of glutamatergic neurobiology and aid assessment of novel therapies for cognitive deficits such as those seen in schizophrenia

Perfusion MRI Indexes Variability in the Functional Brain Effects of Theta-Burst Transcranial Magnetic Stimulation

Transcranial Magnetic Stimulation (TMS) is an important tool for testing causal relationships in cognitive neuroscience research. However, the efficacy of TMS can be variable across individuals and difficult to measure. This variability is especially a challenge when TMS is applied to regions without well-characterized behavioral effects, such as in studies using TMS on multi-modal areas in intrinsic networks. Here, we examined whether perfusion fMRI recordings of Cerebral Blood Flow (CBF), a quantitative measure sensitive to slow functional changes, reliably index variability in the effects of stimulation. Twenty-seven participants each completed four combined TMS-fMRI sessions during which both resting state Blood Oxygen Level Dependent (BOLD) and perfusion Arterial Spin Labeling (ASL) scans were recorded. In each session after the first baseline day, continuous theta-burst TMS (TBS) was applied to one of three locations: left dorsolateral prefrontal cortex (L dlPFC), left anterior insula/frontal operculum (L aI/fO), or left primary somatosensory cortex (L S1). The two frontal targets are components of intrinsic networks and L S1 was used as an experimental control. CBF changes were measured both before and after TMS on each day from a series of interleaved resting state and perfusion scans. Although TBS led to weak selective increases under the coil in CBF measurements across the group, individual subjects showed wide variability in their responses. TBS-induced changes in rCBF were related to TBS-induced changes in functional connectivity of the relevant intrinsic networks measured during separate resting-state BOLD scans. This relationship was selective: CBF and functional connectivity of these networks were not related before TBS or after TBS to the experimental control region (S1). Furthermore, subject groups with different directions of CBF change after TBS showed distinct modulations in the functional interactions of targeted networks. These results suggest that CBF is a marker of individual differences in the effects of TBS

Many Labs 2: Investigating Variation in Replicability Across Samples and Settings

We conducted preregistered replications of 28 classic and contemporary published findings, with protocols that were peer reviewed in advance, to examine variation in effect magnitudes across samples and settings. Each protocol was administered to approximately half of 125 samples that comprised 15,305 participants from 36 countries and territories. Using the conventional criterion of statistical significance (p < .05), we found that 15 (54%) of the replications provided evidence of a statistically significant effect in the same direction as the original finding. With a strict significance criterion (p < .0001), 14 (50%) of the replications still provided such evidence, a reflection of the extremely high-powered design. Seven (25%) of the replications yielded effect sizes larger than the original ones, and 21 (75%) yielded effect sizes smaller than the original ones. The median comparable Cohen’s ds were 0.60 for the original findings and 0.15 for the replications. The effect sizes were small (< 0.20) in 16 of the replications (57%), and 9 effects (32%) were in the direction opposite the direction of the original effect. Across settings, the Q statistic indicated significant heterogeneity in 11 (39%) of the replication effects, and most of those were among the findings with the largest overall effect sizes; only 1 effect that was near zero in the aggregate showed significant heterogeneity according to this measure. Only 1 effect had a tau value greater than .20, an indication of moderate heterogeneity. Eight others had tau values near or slightly above .10, an indication of slight heterogeneity. Moderation tests indicated that very little heterogeneity was attributable to the order in which the tasks were performed or whether the tasks were administered in lab versus online. Exploratory comparisons revealed little heterogeneity between Western, educated, industrialized, rich, and democratic (WEIRD) cultures and less WEIRD cultures (i.e., cultures with relatively high and low WEIRDness scores, respectively). Cumulatively, variability in the observed effect sizes was attributable more to the effect being studied than to the sample or setting in which it was studied