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.

[EX Q]: Context: Early metastasis in node-negative breast cancer indicates that breast cancer cells obviously can bypass the lymph nodes and disseminate directly hematogenous to distant organs. For this purpose, we evaluated the prognostic value of blood-borne, HER2-positive circulating tumor cells (CTC) in the peripheral blood from 42 breast cancer patients with a median follow-up of 95 months.', 'Cells were isolated by the patented combined buoyant density gradient and immunomagnetic separation procedure and analyzed by immunocytochemistry.', 'We detected one to eight CTCs in the peripheral blood of 17 of 35 patients (48.6%) presenting no overt metastasis. As a positive control, 7 of 7 (100%) patients with metastatic disease presented positive. Healthy persons and patients (n = 32) operated for nonmalignant diseases presented negative for CTCs. The presence and frequency of HER2-positive CTCs correlated with a significantly decreased disease-free survival (P < 0.005) and overall survival (P < 0.05). Interestingly, in 12 patients with HER2-positive CTCs, the primary tumor was negative for HER2 as assessed by immunohistochemical score and fluorescence in situ hybridization.
Answer: This study provides some evidence of a prognostic effect of HER2-positive CTCs in stage I to III breast cancer. Future studies have to determine the outcome of patients treated with HER2-targeting therapies with respect to HER2-positive CTC levels because it is not unlikely that high levels of HER2-positive CTCs reflect the activity of the tumor and may predict response to trastuzumab.
[EX A]: Do hER2-positive circulating tumor cells indicate poor clinical outcome in stage I to III breast cancer patients?

[EX Q]: Context: Small studies suggest exogenous estrogen may improve vitamin D status, but the etiology is unclear because women who use hormones may make lifestyle choices that differentially affect vitamin D status.', 'Our objective was to investigate the association between use of hormonal contraception and 25-hydroxy-vitamin D (25(OH)D).', 'We used linear regression modeling of cross-sectional data to estimate percent change in season-adjusted serum 25(OH)D with estrogen use after adjustment for other factors.', 'At the enrollment clinic visit (2010-2012) into a cohort study of uterine fibroids, each subject provided a blood sample, had anthropomorphic variables and skin reflectance measured, and answered questionnaires on demographics, dietary and supplement intake, contraceptive use, reproductive and medical history, and behaviors.', 'A total of 1662 African American women, community volunteers, 23-34 years old, living in the Detroit, Michigan, area were included.', 'None.', 'Serum 25(OH)D was measured.', 'Serum 25(OH)D concentrations were low (70% <20 ng/ml). Current use of an estrogen-containing contraceptive was associated with a 20% (95% confidence interval: 14-27) increase in 25(OH)D after adjustment. There was no increase in 25(OH)D among participants who had used estrogen in the past, but were not current users, indicating that results were unlikely to be due to unmeasured confounding by factors related to contraceptive choice.
Answer: The increase in 25(OH)D with use of estrogen-containing contraceptives raise mechanistic questions regarding the biological pathways involved, and highlights the need for studies that examine possible endogenous estrogen effects on vitamin D.
[EX A]: Does use of Estrogen-Containing Contraception be Associated With Increased Concentrations of 25-Hydroxy Vitamin D?

[EX Q]: Context: Lateral compression pelvic Type I fractures in the elderly population are most often low-energy osteoporosis related fractures. Previous literature comparing pelvic fractures in young versus elderly patients called into question the general consideration of these injuries as benign injuries with favorable prognoses; however, the geriatric population older than 80 years is often underrepresented. This article focuses on the mortality and functional outcomes after low-energy pelvic fractures in a population of patients older than 80 years.', "We prescreened potential subjects in a Level I trauma institution's electronic medical record database between January 1, 2002, and April 30, 2012, to identify isolated lateral compression Type 1 fractures treated nonoperatively in patients older than 80 years. This study was composed of a retrospective review of medical records followed by a prospective survey data collection to examine mechanisms of injury, length of hospital stay, complications, medical comorbidities, ambulatory function, living situation, pain, and 1 year mortality rates.", 'We present a large case series of 85 patients older than 80 years and report a 1-year mortality rate of 20%. We found that patients who were household ambulators or nonfunctional ambulators were five times more likely (24.4% vs. 6.1%) to die within 1 year after injury. Multivariate logistic regression confirmed that the risk of 1-year mortality was significantly higher for household-bound patients compared with community ambulators, independent of sex, smoking, Charlson comorbidity index, or length of hospital stay.
Answer: This is the first study to demonstrate a difference in 1-year mortality between patients who were community ambulators versus those who were household ambulators or nonfunctional ambulators before injury. With our aging population, these findings have important implications. Maintenance of general conditioning and early mobilization with physical therapy after injury is a key part of geriatric orthopedic rehabilitation.
[EX A]:
Is preinjury ambulatory status associated with 1-year mortality following lateral compression Type I fractures in the geriatric population older than 80 years?