Postoperative intra-arterial methylene blue injection of colorectal cancer specimens increases the number of lymph nodes recovered.

AIMS: 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 assigned randomly to either 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 increases significantly the number of lymph nodes recovered in colorectal cancer specimens.

Preoperative interleukin-6 production by mononuclear blood cells predicts survival after radical surgery for colorectal carcinoma.

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.