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.

Context: Current diagnostic tests for gastroesophageal reflux disease (GERD) do not consistently measure chronicity of reflux. Mucosal impedance (MI) is a minimally invasive measurement to assess esophageal conductivity changes due to GERD. We aimed to investigate MI pattern in patients with symptoms of extraesophageal reflux (EER) in a prospective longitudinal cohort study.', 'Patients with potential symptoms of EER undergoing esophagogastroduodenoscopy (EGD) with wireless pH monitoring were studied. Participants included those with erosive esophagitis (E+), normal EGD/abnormal pH (E-/pH+), and normal EGD/normal pH (E-/pH-). MI was measured from the site of injury in patients with E+, as well as at 2, 5, and 10 cm above the squamocolumnar junction (SCJ) in all participants.', 'Forty-one patients with symptoms of EER were studied. MI measurements at 2cm above the SCJ were significantly (P=0.04) different among the three groups, with MI lowest for E+ and greatest for E-/pH- patients. Although not statistically significant, there is a graded increase in median (interquartile range) MI axially along the esophagus at 5cm (P=0.20) and at 10cm (P=0.27) above the SCJ, with those with reflux (E+ and E-/pH+) having a lower MI than those without.
Answer: Patients with symptoms of EER and evidence of acid reflux have an MI lower than those without at 2cm above the SCJ, with a trend at 5cm and 10cm as well. MI may be a tool to assess presence of GERD in patients presenting with EER symptoms.
Is esophageal Mucosal Impedance Pattern Distinct in Patients With Extraesophageal Reflux Symptoms and Pathologic Acid Reflux?

Context: Ovarian cancer is a well-known disease with a poor prognosis. Due to the relatively small number of cases in Taiwan, the outcome and prognostic factors of patients with primary epithelial ovarian carcinoma are unknown.', "We retrospectively studied patients with proven surgical and pathologic (Federation Internationale de Gynecologie et d'Obstetrique) FIGO IIIC primary epithelial ovarian carcinoma. All patients underwent standard staging surgery, including washing cytology, total abdominal hysterectomy, bilateral salpingo-oophorectomy, retroperitoneal lymphadenectomy, infracolic omentectomy and excisional biopsy of all suspicious lesions followed by adjuvant chemotherapy with four to 12 courses of cyclophosphamide, epirubicin and cisplatin (CEP) or cyclophosphamide, adriamycin and cisplatin (CAP) intravenously, every three weeks. To avoid the coeffects of chemotherapy and surgical procedures upon the outcome, patients who received paclitaxel-based regimens or underwent incomplete surgery were excluded. Ninety-eight patients from 1990 to 1996 were identified.", 'The mean follow-up time was 28.7 months, ranging from 5.4 months to 105.9 months. The cumulative five-year disease-free survival rate for all patients was 31.6%. Optimal debulking surgery was completed in 41.8% of patients, which contributed to long-term patient survival (54% vs 16%, p < 0.0001), compared to patients without optimal debulking surgery. Optimal debulking surgery was the only statistically significant independent prognostic factor for five-year disease-free survival using multivariate analysis.
Answer: To improve survival of patients with FIGO stage IIIC epithelial ovarian carcinoma, optimal debulking surgery should be performed as the initial form of surgical intervention.
Is optimal debulking surgery an independent prognostic factor in patients with FIGO IIIC primary epithelial ovarian carcinoma?

Context: We evaluated whether CK19, one of the main cytoskeleton proteins of epithelial cells, is released as full-length protein from viable tumor cells and whether this property is relevant for metastatic progression in breast cancer patients.', 'EPISPOT (EPithelial ImmunoSPOT) assays were performed to analyze the release of full-length CK19 by carcinoma cells of various origins, and the sequence of CK19 was analyzed with mass spectrometry. Additional functional experiments with cycloheximide, Brefeldin A, or vincristine were done to analyze the biology of the CK19-release. CK19-EPISPOT was used to detect disseminated tumor cells in bone marrow (BM) of 45 breast cancer patients who were then followed up over a median of 6 years.', 'CK19 was expressed and released by colorectal (HT-29, HCT116, Caco-2) and breast (MCF-7, SKBR3, and MDA-MB-231) cancer cell lines. The CK19-EPISPOT was more sensitive than the CK19-ELISA. Dual fluorescent EPISPOT with antibodies against different CK19 epitopes showed the release of the full-length CK19, which was confirmed by mass spectrometry. Functional experiments indicated that CK19 release was an active process and not simply the consequence of cell death. CK19-releasing cells (RCs) were detectable in BM of 44% to 70% of breast cancer patients. This incidence and the number of CK19-RCs were correlated to the presence of overt metastases, and patients with CK19-RCs had a reduced survival as compared with patients without these cells (P = 0.025, log-rank test; P = 0.0019, hazard ratio, 4.7; multivariate analysis).
Answer: Full-length CK19 is released by viable epithelial tumor cells, and CK19-RCs might constitute a biologically active subset of breast cancer cells with high metastatic properties.
Is full-length cytokeratin-19 released by human tumor cells : a potential role in metastatic progression of breast cancer?