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.

To investigate the influence of clinical characteristics including nutritional markers on postoperative survival in patients undergoing total gastrectomy (TG) for gastric cancer (GC).', 'One hundred fifty-four patients were enrolled. Uni- and multivariate analyses using the Cox proportional hazard model were performed to explore the most valuable clinical characteristic that was associated with postoperative survival.', 'Multivariate analysis using twelve clinical characteristics selected from univariate analyses revealed that age ( 72/>72), carcinoembryonic antigen ( 20/>20) (ng/ml), white blood cell count ( 9.5/>9.5) ( 10(3)/mm(3)), prognostic nutritional index (PNI) ( 45/>45) and lymph node metastasis (negative/positive) were associated with postoperative survival. Kaplan-Meier analysis and log-rank test showed that patients with higher PNI (>45) had a higher postoperative survival rate than those with lower PNI ( 45) (p<0.001).
Is prognostic nutritional index associated with survival after total gastrectomy for patients with gastric cancer?