Task: Question Generation
Input (English): Plasma VEGF levels increase after minimally invasive colorectal resection (MICR) and remain elevated for 2-4 weeks. VEGF induces physiologic and pathologic angiogenesis by binding to endothelial cell (EC) bound VEGF-Receptor-1 (VEGFR1) and VEGFR2. Soluble forms of these receptors sequester plasma VEGF, decreasing the amount available to bind to EC-bound receptors. Ramifications of surgery-related plasma VEGF changes partially depend on plasma levels of sVEGFR1 and sVEGFR2. This study assessed perioperative sVEGFR1 and sVEGFR2 levels after MICR in patients with colorectal cancer.', 'Forty-five patients were studied; blood samples were taken from all patients preoperatively (preop) and on postoperative days (POD) 1 and 3; in most a fourth sample was drawn between POD 7-30. Late samples were bundled into two time points: POD 7-13 and POD 14-30. sVEGFR1 and sVEGFR2 levels were measured via ELISA. sVEGFR2 data are reported as mean +/- SD and were assessed with the paired samples t test. sVEGFR1 data were not normally distributed. They are reported as median and 95% confidence interval (CI) and were assessed with the Wilcoxon signed-Rank test (p < 0.05).', 'Preoperatively, the mean plasma sVEGFR2 level (7583.9 pg/ml) was greater than the sVEGFR1 result (98.3 pg/ml). Compared with preop levels, sVEGFR2 levels were significantly lower on POD 1 (6068.2 pg/ml, +/-2034.5) and POD 3 (6227.6 pg/ml, +/-2007.0), whereas sVEGFR1 levels were significantly greater on POD 1 (237.5 pg/ml; 95% CI, 89.6-103.5), POD 3 (200.2 pg/ml; 95% CI, 159-253), and POD 7-13 (102.9 pg/ml; 95% CI, 189.7-253). No differences were found on POD 7-13 for sVEGFR2 or POD 14-30 for either protein.
Output (English): Is minimally invasive colon resection for malignant colonic conditions associated with a transient early increase in plasma sVEGFR1 and a decrease in sVEGFR2 levels after surgery?