Minimally invasive colorectal resection is associated with a transient increase in plasma hepatocyte growth factor levels early after surgery for colon cancer.

INTRODUCTION: Surgery's impact on blood levels of hepatocyte growth factor (HGF), a potent angiogenic factor, is unknown. Preoperative (PreOp) HGF blood levels are elevated in patients with colorectal cancer (CRC) and correlate with disease stage and prognosis. This study's purpose was to determine plasma HGF levels after minimally invasive colorectal resection (MICR) in patients with CRC. METHODS: Clinical and operative data were collected. Blood samples were obtained in all patients PreOp and on postoperative day (POD) 1 and 3; in some, samples were taken during weeks 2 and 3 after MICR. Late samples were bundled into 7-day time blocks. HGF levels were determined via enzyme-linked immunosorbent assay in duplicate. Student's t test was used to analyze the data (significance, P < .0125 after Bonferroni correction). RESULTS: A total of 28 CRC patients who underwent MICR were studied. Most had right, sigmoid, or left segmental colectomy. The mean plasma HGF level was higher on POD 1 (2417 ± 1476 pg/mL, P < .001) and POD 3 (2081 ± 1048 pg/mL, P < .001) when compared with PreOp levels (1045 ± 406 pg/mL). Plasma levels were back to baseline by the second (1100 ± 474 pg/mL, P = .64) and third postoperative weeks (1010 ± 327 pg/mL, P = .51). CONCLUSION: MICR for CRC is associated with a 1.9- to 2.3-fold increase in plasma HGF levels during the first 3 PODs after which levels normalize. This transient increase may briefly promote angiogenesis and the growth of residual tumor cells.

Minimally invasive colorectal resection for cancer is associated with a short-lived decrease in soluble Tie-2 receptor levels, which may transiently inhibit VEGF-mediated angiogenesis (via altered blood levels of free Ang-1 and Ang-2).

BACKGROUND: Angiopoetin- (Ang-) 1 inhibits and Ang-2 promotes VEGF-mediated angiogenesis via binding to endothelial cell-bound Tie-2 receptor (Tie-2). After minimally invasive colorectal resection (MICR), Ang-1 levels decrease and Ang-2 levels increase, which may stimulate angiogenesis in wounds and residual tumor foci. Soluble Tie-2 (sTie-2) modulates the effects of free Ang-1 and Ang-2 by binding to them. This study assessed perioperative MICR plasma sTie-2 levels. METHODS: Blood samples were taken preoperatively (PreOp) and on postoperative days (POD) 1 and 3 from 50 cancer and 53 benign disease MICR patients. In a subgroup, a fourth sample was taken between POD7 and POD13 and bundled as a single time point. sTie-2 levels (ng/ml) were determined via ELISA. The mean and SD were determined at each time point. The t test used for analysis. RESULTS: PreOp plasma sTie-2 levels were significantly higher in the benign group (27.6 ± 10.2) than in the cancer group (22.9 ± 7.9). A significant drop from PreOp occurred in sTie-2 levels in the cancer group on POD1 (20.0 ± 7.4) and POD3 (21.0 ± 6.6) and in the benign group on POD1 (24.8 ± 9.1). The benign group's POD3 and the cancer group's POD7-13 sTie-2 levels were statistically similar to the PreOp levels while the benign group's POD7-13 level was significantly higher. CONCLUSION: PreOp sTie-2 levels were significantly lower in cancer patients. MICR is associated with a significant short-lived decrease in plasma sTie-2 levels in cancer patients on POD1 and 3, which may briefly inhibit VEGF-mediated angiogenesis. The benign group's early results were similar.

Increased utilization of flexible endoscopic methods during colorectal resection over a 3-year period.

INTRODUCTION: Intraoperative endoscopy (IE) is performed during some colorectal resections (CRR) mainly to inspect circular stapled anastomoses (CSA) and to locate small neoplasms. This study's purpose was to determine how often rigid and flexible lower endoscopic methods were used during CRR by one colorectal surgeon over three 1-year periods. METHODS: Data concerning the indication for surgery and IE, type of resection, and the use of rigid and flexible methods were obtained from a prospective database and from hospital charts during Period 1 (P1), 1/1/05 to 12/31/05; P2, 7/1/06 to 6/31/07; and P3, 7/01/07 to 6/30/08. The endoscopic CO2 insufflation device was introduced during P2. The utilization rates (UR) for rigid and flexible methods and the overall UR in each time period were compared. The chi(2) and Fisher exact test were used for analysis. RESULTS: No significant differences were found in overall endoscopy UR between periods (94-109/per period.) A significantly higher flexible UR was noted during P3 (43.1% of all CRR) than during P1 (18.6%, P < .001) or P2 (28.7%, P < .03). There was a concomitant significant drop in the rigid UR during Period 3 (1.8% of all CRR) when compared with P1 (24.5%, P < .001) or P2 (27.7%, P < .001). CONCLUSION: The overall UR did not significantly vary; however, during P3 the flexible UR increased whereas the rigid UR decreased (vs P1, P2; P < .05). The addition of extra endoscopes and an endoscopic CO2 insufflation device to the operating room coincided with increased flexible UR.