Given a passage with a context and an answer, construct a question on the basis of the information present in the passage. Construct the question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) it answer uses text phrases from the passage. Avoid creating questions that (i) can't be answered correctly without actually understanding the passage and (ii) uses the same words or phrases given in the passage.

Q: Context: The aim of this study was to determine the clinical significance and prognostic impact of extranodal metastasis (EM) in gastric carcinoma.', 'The study included 1023 patients who underwent gastrectomy with lymphadenectomy for primary gastric carcinoma between January 1993 and December 1996. EM was defined as the presence of tumour cells in extramural soft tissue that was discontinuous with either the primary lesion or locoregional lymph nodes.', "EM was detected in 146 (14.3 per cent) of the 1023 patients and in 1060 (3.0 per cent) of the 35 811 nodules that were retrieved as 'lymph nodes' from adipose connective tissues. The incidence of EM was significantly higher in patients with tumours that were large (diameter 10 cm or more), infiltrative, deeply invading or undifferentiated and in those with lymph node, peritoneal or liver metastases, or lymphatic or vascular involvement. After curative operation overall survival was significantly worse for patients with EM than those without (P < 0.001). Multivariate analysis identified EM as an independent prognostic factor (hazard ratio 1.82 (95 per cent confidence interval 1.23 to 2.71); P = 0.003).
Answer: EM is an independent prognostic factor and should therefore be included in the tumour node metastasis (TNM) staging system.

A: Is extranodal metastasis an indicator of poor prognosis in patients with gastric carcinoma?
****
Q: Context: To investigate whether social contact and support received during hospitalization for acute ischemic stroke predict depression and daily life functioning three months later.', 'Prospective observational study using Ecological Momentary Assessments to evaluate the number of social contacts as well as social support received from family, friends and medical staff within 24hours following admission for stroke. Patients also monitored depression symptoms and behavior in real-time and in daily life contexts three months later.', 'A university hospital acute stroke unit.', 'Thirty-four mild ischemic stroke patients.', 'None.', 'One-day Ecological Momentary Assessments immediately following stroke collected information concerning perceived social support, number of social contacts and depression symptoms. Ecological Momentary Assessments was repeated three months later and addressed depression levels as well as activities of daily living, such as working, cooking, shopping and housework.', 'The number of social interactions received at hospitalization did not predict three-month outcomes. However, a better quality of moral support from friends and family immediately after stroke was associated with decreases in later depression levels (p=0.041) and increases in activities of daily living (p=0.011). Material support from friends and family was associated with increases in activities of daily living (p=0.012). No effect was observed for support received from medical staff.
Answer: Patient perceptions of better support quality, and not quantity, immediately following mild stroke, are associated with better behavioral and emotional outcomes three months later.

A: Is very early social support following mild stroke associated with emotional and behavioral outcomes three months later?
****
Q: Context: Chronic high-frequency electrical deep brain stimulation (DBS) of the subcallosal cingulate region is currently being investigated clinically as a therapy for treatment of refractory depression. Experimental DBS of the homologous region, the ventromedial prefrontal cortex (VMPFC), in rodent models has previously demonstrated anti-depressant-like effects. Our goal was to determine if structural remodeling accompanies the alterations of brain function previously observed as a result of chronic DBS.', 'Here we applied 6h of high-frequency bilateral VMPFC DBS daily to 8 9-week old C57Bl/6 mice for 5days. We investigated the "micro-lesion" effect by using a sham stimulation group (8 mice) and a control group (8 mice with a hole drilled into the skull only). Whole brain anatomy was investigated post-mortem using high-resolution magnetic resonance imaging and areas demonstrating volumetric expansion were further investigated using histology and immunohistochemistry.', 'The DBS group demonstrated bilateral increases in whole hippocampus and the left thalamus volume compared to both sham and control groups. Local hippocampal and thalamic volume increases were also observed at the voxel-level; however these increases were observed in both DBS and sham groups. Follow-up immunohistochemistry in the hippocampus revealed DBS increased blood vessel size and synaptic density relative to the control group whereas the sham group demonstrated increased astrocyte size.
Answer: Our work demonstrates that DBS not only works by altering function with neural circuits, but also by structurally altering circuits at the cellular level. Neuroplastic alterations may play a role in mediating the clinical efficacy of DBS therapy.

A:
Does deep brain stimulation of the ventromedial prefrontal cortex cause reorganization of neuronal processes and vasculature?
****