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: 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.

A: Do hER2-positive circulating tumor cells indicate poor clinical outcome in stage I to III breast cancer patients?
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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.

A: Does use of Estrogen-Containing Contraception be Associated With Increased Concentrations of 25-Hydroxy Vitamin D?
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Q: Context: Studies that investigate the subjective benefit from a bone conduction implant (BCI) sound processor in patients with single-sided sensorineural deafness (SSD) have been limited to examining short- and mid-term benefit. In the current study, we performed a survey among 44 SSD BCI users with a median follow-up time of 50 months.', 'Forty-four experienced SSD BCI users participated in the survey, which consisted of the Abbreviated Profile of Hearing Aid Benefit, the Single-Sided Deafness Questionnaire, the Short Hearing Handicap Inventory for Adults, and a self-made user questionnaire. For patients with tinnitus, the Tinnitus Questionnaire was also completed. The results of the survey were correlated with contralateral hearing loss, age at implantation, duration of the hearing loss at the time of implantation, duration of BCI use, and the presence and burden of tinnitus.', 'In total, 86% of the patients still used their sound processor. The Abbreviated Profile of Hearing Aid Benefit and the Short Hearing Handicap Inventory for Adults show a statistically significant overall improvement with the BCI. The Single-Sided Deafness Questionnaire and the user questionnaire showed that almost 40% of the patients reported daily use of the sound processor. However, the survey of daily use reveals benefit only in certain circumstances. Speech understanding in noisy situations is rated rather low, and 58% of all patients reported that their BCI benefit was less than expected.
Answer: The majority of the patients reported an overall improvement from using their BCI. However, the number of users decreases during a longer follow-up time and patients get less enthusiastic about the device after an extended period of use, especially in noisy situations. However, diminished satisfaction because of time-related reductions in processor function could not be ruled out.

A:
Do long-term subjective benefit with a bone conduction implant sound processor in 44 patients with single-sided deafness?
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