International audienceAims: The aim of this study was to determine the possible advantage of intra-arterial injection of methylene blue with a view to improving lymph node recovery in postoperative examination of colorectal cancer specimens. Methods and results: Thirty-two colorectal cancer specimens were randomly assigned either to dissection with intra-arterial methylene blue injection or to routine dissection (without methylene blue injection). Immediately postoperatively, the specimens in the staining group were injected intra-arterially with methylene blue dye. The two procedures were compared with respect to the number of lymph nodes recovered. The number of recovered lymph nodes was significantly higher in the intra-arterial methylene blue injection group than in the group investigated with routine procedures (P < 0.0001). Conclusion: The intra-arterial methylene blue injection method is fairly easy to use postoperatively and significantly increases the number of lymph nodes recovered in colorectal cancer specimens

BACKGROUND.Colorectal cancer is one of the most common forms of cancer in the Western world. Staging based on histopathology is currently the most accurate predictor of outcome after surgery. Colorectal cancer is curable if treated at an early stage (stage I‐III). However, for tumors in stages II and III there is a great need for tests giving more accurate prognostic information defining the patient population in need of closer follow‐up and/or adjuvant therapy. Furthermore, tests that provide prognostic information preoperatively could provide a guide both for preoperative oncologic treatment and the surgical procedure.METHODS.Peripheral blood mononuclear cells (PBMCs) were isolated preoperatively, within a week before primary surgery, from 39 patients undergoing surgery for colorectal cancer. The PBMCs were cultured in vitro for 24 hours in the presence of autologous serum and lipopolysaccharide (LPS). Interleukin‐6 (IL‐6) production was measured with enzyme‐linked immunosorbent assay (ELISA). Staging based on histopathology was performed in all patients. Patients were followed for at least 54 months.RESULTS.A production of >5000 pg/mL of IL‐6 identified colorectal cancer patients with a poor prognosis. Eight out of 13 patients with >5000 pg/mL IL‐6 died from cancer within the follow‐up period, whereas no cancer‐related deaths were recorded among 21 patients with 5000 pg/mL IL‐6 or less. A multivariate Cox regression analysis, stratified for T‐ and N‐stage, identified IL‐6 production as an independent prognostic factor.CONCLUSIONS.IL‐6 production in vitro by PBMC can predict survival after radical surgery for colorectal cancer. Cancer 2007. © 2007 American Cancer Society.

Colorectal cancer (CRC) is one of the most common forms of cancer in the Western world with an estimated yearly incidence rate of 77 per 100 000 in North America. Besides histopathological staging, there is a great need for tests giving more accurate prognostic information defining the patient population in need of closer follow-up and/or adjuvant therapy. Elevated serum levels of IL-6 have been found in patients with CRC. The source of the serum IL-6 is still unclear. Peripheral blood mononuclear cells (PBMC) were isolated preoperatively (within a week before surgery) from 34 patients undergoing radical surgery for colorectal cancer. The PBMCs were cultured for 24 hours in the presence of autologous serum and LPS. IL-6 production was measured with ELISA. Staging based on histopathology was performed in all patients. A production of &gt;5000 pg/ml of IL-6 identified CRC patients with a poor prognosis. Eight out of thirteen patients with &gt;5000 pg/ml IL-6 died from cancer within the follow-up period (at least 54 months) whereas no cancer related deaths were recorded among twenty-one patient with 5000 pg/ml IL-6 or less. IL-6 production was identified as an independent prognostic factor. These data support the hypothesis that the adaptive immune system is of importance for tumour progression and that immunological parameters can serve as useful as prognostic and predictive tools in cancer management.