Effects of pneumoperitoneum on tumor implantation with decreasing tumor inoculum
INTRODUCTION: The aim of this study was to determine the effect of pneumoperitoneum on the rate of trocar-site implantation with decreasing inoculum of cancer cells. METHODS: A total of 0.5 ml of GW-39 human colon cancer cell suspensions at 1 percent (∼3.2×105 cells) and at 0.5 percent (∼1.6×105 cells; v/v) were injected into the abdomen of hamsters through a midline incision. Animals in each group were randomized to receive either pneumoperitoneum (1 percent=33; 0.5 percent=43) or not (1 percent=32; 0.5 percent=39). Gross and microscopic tumor implants were documented seven weeks later at four trocar sites. RESULTS: In the 1 percent group, pneumoperitoneum significantly increased trocar-site tumor implants from 50 to 71 percent (P<0.001). Pneumoperitoneum also resulted in the following: 1) more frequent involvement of all four concurrent sites (38vs. 10 percent;P<0.02); 2) more frequent palpable tumors (13vs. 5 percent;P<0.01); 3) larger tumor mass (2.1±0.6 gvs. 0.2±0.1 g;P<0.02). In the 0.5 percent group, pneumoperitoneum did not significantly increase trocar-site tumor implants, and it did not result in a larger tumor mass. The percent increase in trocar-site implants owing to pneumoperitoneum was influenced by the amount of tumor inoculum (21 percent in the 1 percent group; 10 percent in the 0.5 percent group). The mass of palpable tumor implants after pneumoperitoneum decreased with decreased inoculum: 1 percent =2.1±0.6 g; 0.5 percent=0.3±0.1 g (P<0.0001). CONCLUSIONS: Pneumoperitoneum significantly increased both tumor implantation rate and mass when ∼3.2×105 colon cancer cells were injected into the peritoneal cavity. These effects of pneumoperitoneum diminished with one-half as many tumor cells injected in the peritoneal cavity.
Key wordsTumor Implants Trocar Port Recurrence Colon cancer Colectomy Laparoscopy Pneumoperitoneum
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- 1.Wexner SD, Cohen SM. Port site metastases after laparoscopic colorectal surgery for cure of malignancy. Br J Surg 1995;82:295–8.Google Scholar
- 2.Hughes ES, McDermott FT, Polglase AL, Johnson WR. Tumor recurrence in the abdominal wall scar tissue after large-bowel cancer surgery. Dis Colon Rectum 1983;26:571–2.Google Scholar
- 3.Jones DB, Guo LW, Reinhard MK,et al. Impact of pneumoperitoneum on trocar site implantation of colon cancer in hamster model. Dis Colon Rectum 1995;38:1182–8.Google Scholar
- 4.Wu JS, Brasfield EB, Guo LW,et al. Implantation of colon cancer at trocar sites is increased by low pressure pneumoperitoneum. Surgery 1997;122:1–7.Google Scholar
- 5.Vacca LL. Laboratory manual of histochemistry. New York: Raven Press, 1985.Google Scholar
- 6.Stramignoni D, Bowen R, Atkinson B, Scholm J. Differential reactivity of monoclonal antibodies with human colon adenocarcinomas and adenomas. Int J Cancer 1982;31:543–52.Google Scholar
- 7.Alexander RJ, Jaques BC, Mitchell KG. Laparoscopically assisted colectomy and wound recurrence. Lancet 1993;341:249–50.Google Scholar
- 8.O'Rourke N, Price PM, Kelly S, Sikora K. Tumour inoculation during laparoscopy. Lancet 1993;342:368–71.Google Scholar
- 9.Nduka CC, Monson JR, Menzies-Gow N, Darzi A. Abdominal wall metastases following laparoscopy. Br J Surg 1994;81:648–52.Google Scholar
- 10.Fusco MA, Paluzzi MW. Abdominal wall recurrence after laparoscopic-assisted colectomy for adenocarcinoma of the colon: report of a case. Dis Colon Rectum 1993;36:858–61.Google Scholar
- 11.Wade TP, Comitalo JB, Andrus CH, Goodwin MN, Kaminski DL. Laparoscopic cancer surgery: lessons from gallbladder cancer. Surg Endosc 1994;8:698–701.Google Scholar
- 12.Jacobi C, Keller HW, Said S. Implantation metastasis of unsuspected gallbladder carcinoma after laparoscopy [abstract]. Br J Surg 1994;81(Suppl):82.Google Scholar