Pringle maneuver induces hepatic metastasis by stimulating the tumor vasculature.

BACKGROUND/AIMS: The Pringle maneuver is traditionally used to avoid hemorrhage during hepatectomy for hepatic metastasis. However, metastasis can occur under ischemic conditions due to some unknown mechanism. METHODOLOGY: An orthotopic model of murine colon cancer was established in syngeneic BALB/c mice. Viable CT-26 cells were implanted into the spleen of these mice. The mice underwent a laparotomy 5 days after the implantation and the hepato-duodenal ligament was clamped for 0 or 10 minutes (Pringle maneuver). The mice were sacrificed 7 days after this maneuver and the number of hepatic metastasis were counted. RESULTS: The mice that underwent the maneuver developed a greater number of hepatic metastasis. An immunohistochemical analysis revealed that the expression of microvessel density, VEGF and KDR/Flk-1 were higher in the hepatic metastasis in the mice treated with the maneuver. In addition, the mice which were treated by the maneuver had a higher level VEGF in the serum. CONCLUSION: These data suggest that the Pringle maneuver induces hepatic metastasis by stimulating the overexpression of tumor vasculature.

Experience of Altemeier's procedures for a complete rectal prolapse.

BACKGROUND/AIMS: Many patients with a complete rectal prolapse tend to be old. Therefore, surgeons tend to choose a surgical procedure associated with minimal stress. However, the recurrence rate is problematic. Altemeier's procedure causes minimal stress. This procedure is often selected for performing a complete rectal prolapse. Usually, a rectosigmoidectomy, is performed with levatoroplasty and anastomosis of the anal tube and the colon under spinal anesthesia. This procedure was applied for a complete rectal prolapse and the outcomes of this procedure were analyzed. METHODOLOGY: From 2000 August to 2006 January, 13 patients underwent this procedure. The patients ranged from 27 to 89 years of age (median 76 years). The length of the escaped enteric canal ranged from 7.0 to 20.0cm. RESULTS: All patients underwent the procedure under spinal anesthesia. The surgical time was 113 +/- 20 minutes. There were two postoperative complications which were both treated conservatively. One recurrent case was recognized. CONCLUSION: Altemeier's procedure was associated with a minimum of stress and the recurrence rate was low (7.6%). Because a complete rectal prolapse is caused by the fragility of the anal sphincter muscle and levator ani muscle, this procedure is considered to be effective and appropriate.

Is laparoscopic surgery a contraindication in patients with severe senile kyphosis?

BACKGROUND/AIMS: The japanese population have the longest-life expectancy in the world. Accordingly, older patients with colorectal cancer with senile kyphosis caused by aging or osteoporosis also increase. Laparoscopic surgery is minimally-invasive, and performance on severe kyphotic patients may cause difficulty to approach a narrow abdomen. To determine whether laparoscopic surgery is safe and feasible in patients with severe senile kyphosis. METHODS: Laparoscopic operations under general anesthesia were undertaken with the patients in lithotomy position. Intraoperative difficulties were compared with normal laparoscopic approach. RESULTS: Working space was divided by right costal arch during right hemicolectomy for right sided colon cancer. For sigmoid colon cancer, dissection of lymph node and anastomosis were completed with much difficulty because the pelvic space was occupied with small intestine. However, the postoperative course was uneventful despite impaired lung function in all cases. CONCLUSIONS: Severe senile kyphosis is not a contraindication for minimally invasive technique applied to colorectal cancer patients.

Clinical usefulness of diffusion-weighted imaging using low and high b-values to detect rectal cancer.

PURPOSE: The purpose of this study was to assess the potential role of diffusion-weighted imaging (DWI) using low and high b-values to detect rectal cancer. METHODS: The subjects were 15 patients diagnosed endoscopically with rectal cancer (m in 1 patient, sm in 0, mp in 3, ss in 7, se in 1, a in 3) and 20 patients diagnosed endoscopically with colon cancer and no other lesions (control group). Magnetic resonance imaging was performed using a 1.5T system. DWI was performed in the axial plane using echo planar imaging sequence (repetition time/echo time 1200/66, field of view 306x350 mm, reconstruction matrix 156x256, pixel size 2.0x1.4x8.0 mm) and acquired with 2 b-values (50 and 800 s/mm2). Low and high b-value DW images were analyzed visually. A lesion was positive by detection of a focal area of high signal in the rectum in high b-value images. The apparent diffusion coefficient (ADC) values of areas of high signal in high b-value images were calculated from the low and high b-value images. RESULTS: High b-value images enabled visualization of all 15 rectal cancers. In the control group, 13 cases were classified as negative and 7 cases as positive for rectal cancer. Sensitivity for detection of rectal cancer was 100% (15/15), and specificity was 65% (13/20). The mean ADC values in 7 patients with false-positive lesions and in 15 patients with rectal cancer were 1.374x10(-3) mm2/s (standard deviation [SD]: 0.157) and 1.194x10(-3) mm2/s (SD: 0.152), respectively (P=0.026). CONCLUSION: DWI with low and high b-values may be used to screen for rectal cancer.