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.

Example Input: Context: To evaluate the clinical value of staging laparoscopy in treatment decision-making for advanced gastric cancer (GC).', 'Clinical data of 582 patients with advanced GC were retrospectively analyzed. All patients underwent staging laparoscopy. The strength of agreement between computed tomography (CT) stage, endoscopic ultrasound (EUS) stage, laparoscopic stage, and final stage were determined by weighted Kappa statistic (Kw). The number of patients with treatment decision-changes was counted. A (2) test was used to analyze the correlation between peritoneal metastasis or positive cytology and clinical characteristics.', 'Among the 582 patients, the distributions of pathological T classifications were T2/3 (153, 26.3%), T4a (262, 45.0%), and T4b (167, 28.7%). Treatment plans for 211 (36.3%) patients were changed after staging laparoscopy was performed. Two (10.5%) of 19 patients in M1 regained the opportunity for potential radical resection by staging laparoscopy. Unnecessary laparotomy was avoided in 71 (12.2%) patients. The strength of agreement between preoperative T stage and final T stage was in almost perfect agreement (Kw = 0.838; 95% confidence interval (CI): 0.803-0.872; P < 0.05) for staging laparoscopy; compared with CT and EUS, which was in fair agreement. The strength of agreement between preoperative M stage and final M stage was in almost perfect agreement (Kw = 0.990; 95% CI: 0.977-1.000; P < 0.05) for staging laparoscopy; compared with CT, which was in slight agreement. Multivariate analysis revealed that tumor size ( 40 mm), depth of tumor invasion (T4b), and Borrmann type (III or IV) were significantly correlated with either peritoneal metastasis or positive cytology. The best performance in diagnosing P-positive was obtained when two or three risk factors existed.
Answer: Staging laparoscopy can improve treatment decision-making for advanced GC and decrease unnecessary exploratory laparotomy.
Example Output: Does staging laparoscopy improve treatment decision-making for advanced gastric cancer?

Example Input: 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.
Example Output: Is optimal debulking surgery an independent prognostic factor in patients with FIGO IIIC primary epithelial ovarian carcinoma?

Example Input: Context: Existing dogma that a female is born with fixed number of eggs was challenged by the detection of stem cells in adult mammalian ovary. Data has accumulated in support of ovarian stem cells (OSCs) proliferation, maintenance in culture, formation of germ cell nests and differentiation into oocytes and primordial follicle assembly using different strategies.', 'Flow cytometry analysis identified >8m OSCs which are DDX1 positive and are considered equivalent to spermatogonial stem cells (SSCs) in testis. Analysis of both ovarian and testicular smears obtained after enzymatic digestion has led to the identification of an additional stem cell population termed very small embryonic-like stem cells (VSELs). VSELs and OSCs/SSCs differ from each other in their size and OCT-4 expression. VSELs express pluripotent markers including nuclear OCT-4 whereas OSCs/SSCs express cytoplasmic OCT-4 suggesting a differentiated state. VSELs can be studied by flow cytometry as small sized cells which are LIN-/CD45-/Sca-1+. We have reported 0.020.008, 0.030.017 and 0.080.03% of total cells as VSELs in normal, chemoablated and after FSH treatment to chemoablated mouse ovary.
Answer: VSELs have remained poorly studied till now because of their very small size and rare occurrence. Spinning cells obtained after enzymatic digestion of ovarian tissue at a speed of 1000G (rather than 1200rpm) throughout processing allows reliable detection of the VSELs by flow cytometry. VSELs exist in aged, chemoablated and non-functional ovary and providing a healthy niche to support their function offers an interesting strategy to manage infertility.
Example Output:
Are ovarian stem cells always accompanied by very small embryonic-like stem cells in adult mammalian ovary?