Given a passage, 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]: Accurate evaluation of the biological behavior of Gastrointestinal stromal tumor and careful selection of patients with a high risk for tumor recurrence are necessary. In the present study, we analyzed prognostic factors in patients with GIST.', 'A total of 214 patients who had undergone curative resection of a localized primary gastric GIST without adjuvant therapy were enrolled in this retrospective study. Prognostic factors were analyzed. The growth pattern was classified as intramural, endoluminal, exoluminal, or mixed- type.', 'On univariate and multivariate analyses, recurrence was predicted by exoluminal or mixed-type (hazard ratio [HR]=3.7, p=0.043), tumor size of >3.5 cm (HR=7.1, p=0.01), and mitotic rate of >5/50 high-power fields (HR=7.9, p<0.001).
[EX A]: Is macroscopic type a prognostic factor for recurrence-free survival after resection of gastric GIST?

[EX Q]: SPARC (secreted protein acidic, rich in cysteine) is a matricellular protein that has been found to be activated in a number of human cancers. More recently, it has been shown to be upregulated in human gastric and colorectal cancer. We therefore wished to address the functional importance of SPARC upregulation to intestinal tumorigenesis in vivo.', 'SPARC upregulation was determined in intestinal adenomas of tumour-prone Apc(Min/+) mice at both the RNA and the protein level. To determine the functional importance of SPARC for intestinal tumorigenesis we then intercrossed Sparc knockout mice with Apc(Min/+) mice (n = 20). Intestinal enterocyte migration was examined using bromodeoxyuridine labelling studies.', 'Levels of murine Sparc and several related proteins were upregulated in adenomas arising in Apc(Min/+) mice. A deficiency of Sparc strongly suppressed adenoma formation in Apc(Min/+) mice (p>or=0.0001). Importantly, a deficiency of Sparc also accelerated enterocyte migration (p = 0.01), as perturbed slow epithelial migration may underpin adenoma formation in the intestine.
[EX A]: Does deficiency of SPARC suppress intestinal tumorigenesis in APCMin/+ mice?

[EX Q]: The clinical significance of the hepatitis B virus core-related antigen (HBcrAg) assay in monitoring the antiviral effects of lamivudine is reviewed.', 'The HBcrAg assay simultaneously measured serum levels of hepatitis B core (HBc) and e (HBe) antigens using monoclonal antibodies which recognize common epitopes of these two denatured antigens.', 'Although serum HBcrAg levels correlated linearly with those of hepatitis B virus (HBV) DNA in natural course, the decrease in HBcrAg was significantly slower than in HBV DNA after initiation of lamivudine administration. We analyzed the clinical significance of HBV DNA and HBcrAg levels to predict the occurrence of lamivudine resistance. HBV DNA measurement may be useful to identify patients who are at high risk of developing lamivudine resistance, and HBcrAg measurement may help to detect patients who are at low risk of drug resistance. The measurement of HBcrAg was also found to be a useful prognosticator for reactivation of hepatitis after cessation of lamivudine administration.
[EX A]:
Is hepatitis B core-related antigen assay useful for monitoring the antiviral effects of nucleoside analogue therapy?