In this task, you are given a passage which has a question and the context. You have to generate an answer to the question based on the information present in the context.

Example Input: Context: With the advent of new and more efficient anti-androgen drugs targeting androgen receptor (AR) in breast cancer (BC) is becoming an increasingly important area of investigation. This would potentially be most useful in triple negative BC (TNBC), where better therapies are still needed. The assessment of AR status is generally performed on the primary tumor even if the tumor has already metastasized. Very little is known regarding discrepancies of AR status during tumor progression. To determine the prevalence of AR positivity, with emphasis on TNBCs, and to investigate AR status during tumor progression, we evaluated a large series of primary BCs and matching metastases and recurrences.', 'AR status was performed on 356 primary BCs, 135 matching metastases, and 12 recurrences using a next-generation Tissue Microarray (ngTMA). A commercially available AR antibody was used to determine AR-status by immunohistochemistry. AR positivity was defined as any nuclear staining in tumor cells 1 %. AR expression was correlated with pathological tumor features of the primary tumor. Additionally, the concordance rate of AR expression between the different tumor sites was determined.', 'AR status was positive in: 87 % (307/353) of primary tumors, 86.1 % (105/122) of metastases, and in 66.7 % (8/12) of recurrences. TNBC tested positive in 11.4 %, (4/35) of BCs. A discrepant result was seen in 4.3 % (5/117) of primary BC and matching lymph node (LN) metastases. Three AR negative primary BCs were positive in the matching LN metastasis, representing 17.6 % of all negative BCs with lymph node metastases (3/17). Two AR positive primary BCs were negative in the matching LN metastasis, representing 2.0 % of all AR positive BCs with LN metastases (2/100). No discrepancies were seen between primary BC and distant metastases or recurrence (n=17).\Question: Is androgen receptor status highly conserved during tumor progression of breast cancer?
Example Output: Most primary (87 %) and metastasized (86.1 %) BCs are AR positive including a significant fraction of TNBCs (11.4 %). Further, AR status is highly conserved during tumor progression and a change only occurs in a small fraction (4.1 %). Our study supports the notion that targeting AR could be effective for many BC patients and that re-testing of AR status in formerly negative or mixed type BC's is recommended.

Example Input: Context: Although the echolucent plaque in carotid stenosis is associated with future ischemic stroke, the predictive value of echogenicity in small and medium size carotid plaques on vascular events has not been thoroughly examined. Thus, we prospectively tested the hypothesis that plaque echogenicity of carotid atheroma can predict the future total cardiovascular events in patients with vascular risk factors.', 'Ultrasound assessment of carotid intima-media complex thickness (IMT) and plaque echogenicity using integrated backscatter (IBS) analysis was performed in 596 patients aged 40 or more, with any history of vascular events or with at least 1 risk factor, who were enrolled between 2001 and 2006 in the Osaka Follow-up Study for Carotid Atherosclerosis, part 2 (OSACA2). We followed the incidence of total cardiovascular events including cerebrovascular events, coronary heart disease (CHD), and peripheral artery disease (PAD) for 6.4 years. We divided the patients into two groups according to the IBS index above (echorich plaques) and under (echolucent plaque) the median value, and calculated the hazard ratios (HR) of the echolucent group compared with the echogenic group in the risk of cardiovascular events.', 'Among 596 patients, carotid stenosis was found only in 87 patients. During the follow-up period, we observed 121 cardiovascular events including 63 cerebrovascular events, 45 CHD cases, and 13 PAD cases. The patients with incident cardiovascular events had larger plaque thickness and lower IBS index than those without incident vascular events. The relative risk of vascular events for echolucent versus echorich plaques was 1.45 (95% confidence interval [CI] 0.99-2.13, p = 0.058) after adjustment for risk factors and plaque thickness. In patients with plaque size above the median value (>2.1 mm), the relative risk of vascular events for echolucent plaques was 1.72 (95% CI 1.06-2.85, p = 0.029), but this association was not observed in patients with plaque size <2.0 mm.\Question: Does echogenicity of medium-to-large carotid plaques predict future vascular events?
Example Output: The association between echogenicity of carotid plaque and incident vascular events is dependent on the plaque size. Echolucent medium-to-large plaques, but not small plaques, are associated with the risk of future total cardiovascular events. This finding suggests that measurement of echolucency in medium-to-large carotid plaques may improve selection of patients at high risk for total vascular events.

Example Input: Context: To determine whether tirofiban can prevent microcirculation dysfunction during delayed percutaneous coronary intervention (PCI) of spontaneously recanalized and severe narrowing coronary artery in patients with acute myocardial infarction.', '62 patients who have a single angiographically confirmed narrowing culprit coronary artery for more than 75% between 7 and 14 days after the onset of acute myocardial infarction were randomly divided into the tirofiban group (32 cases) and the placebo group (30 cases). All the patients received measurement of the index of microcirculatory resistance (IMR) before tirofiban/placebo administration and PCI. After PCI, IMR value was measured again.', 'There was no significant variation between the two groups before PCI (11.67 6.45 of placebo group vs. 14.65 12.45 of tirofiban group, P=0.158). After PCI, the IMR value of the tirofiban group is significantly lower than that of the placebo group (23.63 9.91 of placebo group vs. 16.75 9.98 of tirofiban group, P=0.008).\Question: Does intracoronary injection of tirofiban prevent microcirculation dysfunction during delayed percutaneous coronary intervention in patients with acute myocardial infarction?
Example Output:
Intracoronary injection of tirofiban can significantly prevent the abnormal increase of IMR value during delayed PCI in patients with acute myocardial infarction.