Hmc Shantha Kumara, PhD1, Abhinit Shah, MD1, Erica Pettke, MD1, Xiaohong Yan, MD1, Vesna Cekic, RN1, Nipa D Gandhi, MD2, Melissa A Downing, MD2, Richard L Whelan, MD2. 1Department of Surgery, Mount Sinai West Hospital 1000 Tenth Avenue, Room 3B-61 New York, NY 10019, USA, 2Department of Surgery,Mount Sinai West Hospital,425 West 59th Street,Suite 7B,New York,NY 10019 ,USA
Introduction: It has been shown that plasma levels of 12 proangiogenic proteins are elevated for 1 month after minimally invasive colorectal resection (MICR) and that postoperative (postop) plasma stimulates Endothelial Cell (EC) proliferation and invasion. This proangiogenic plasma may stimulate tumor angiogenesis in patients with residual cancer after MICR. Surgery’s impact on CXCL16, a protein that stimulates EC proliferation and chemotaxis, is unknown. CXCL16 is a transmembrane chemokine found on leukocytes, EC’s and other tissues. A soluble form shed from the membrane likely accounts for its activity. Its receptor, CXCR6, is found on cells at sites of inflammation. CXCL16 and CXCR6 are a ligand-receptor pair thought to be associated with endothelial precursor cell recruitment and angiogenesis in response to pro-inflammatory stimuli. CXCL16 is expressed by a variety of cancers including colorectal cancer (CRC). This study’s purpose is to determine plasma CXCL16 levels in CRC patients before and after MICR.
Method: CRC patients in an IRB approved data/plasma bank who underwent MICR for whom adequate plasma samples were available were eligible. Prospective clinical and demographic data were assessed. Blood samples were taken preoperatively (preop) and at multiple postop time points; plasma was stored at -80°C. Late samples were bundled into 7 day blocks and considered as single time points. CXCL16 levels were analyzed in duplicate using ELISA and results reported as mean ±SD (ng/ml). The Wilcoxon signed rank test was used for analysis (significance p<0.05).
Results: 86 CRC (colon, 73%; rectal 27%) MICR patients (laparoscopic, 63%; hand-assisted, 37%) were studied (40 males /46 female, mean age 64.8± 12.9 years). The mean incision length was 8.4 ± 4.3 cm and mean LOS 6.5± 3.9 days. The cancer stage breakdown was: Stage I, 26%, Stage II, 29%, Stage III, 37% and Stage IV, 4%. The mean preop CXCL6 level was 2.36 ±0.57ng/ml (n=86). Significantly elevated mean plasma levels were noted (p<0.0001) on POD1 (2.82±0.81, n= 86), POD3 (3.12±0.77, n= 82), POD7-13 (3.28±0.88, n=64), POD14-20 (3.03±0.62, n=24), POD 21-27 (3.06±0.67, n= 20, p=0.0003) and on POD 28-34 (3.17±0.43, n= 11, p=0.001) vs. preop levels.
Conclusion: Plasma CXCL6 levels were persistently elevated for 4 weeks after MICR for CRC. The source of the increase early postop may be the acute inflammatory response whereas late elevations may be related to wound healing. Thus, CXCR16 is yet another protein contributing to the proangiogenic makeup of the plasma after MICR. Further studies are needed.
Presented at the SAGES 2017 Annual Meeting in Houston, TX.
Abstract ID: 79072
Program Number: S132
Presentation Session: Colorectal 2
Presentation Type: Podium