Laparoscopic-assisted vs. open surgery for colorectal cancer: comparative study of immune effects.
OBJECTIVE
Our aim was to test the hypothesis that laparoscopic-assisted resection for colorectal cancer has an immunologic advantage over traditional open surgery.


METHODS
Sixteen patients with colorectal cancer were randomized to undergo laparoscopic-assisted resection or open surgery. Basic patient data were recorded, and serum interleukin-6 levels, relative proportions of lymphocytes, and human leukocyte antigen-DR expression on monocytes were determined at specific time intervals.


RESULTS
Operating time was longer for laparoscopic-assisted resection (P=0.02), but analgesic requirements were less (P=0.04). All patients exhibited the following: interleukin-6 levels increased to a maximum at 4 hours and returned to preoperative levels within 48 hours. This response appeared greater for open resection (mean peak level, 313 vs. 173 pg/ml; P=0.25). Relative granulocytosis (P < 0.001) was seen within 48 hours, which was offset by a decrease in percentage of lymphocytes (P < 0.001). Changes in lymphocyte subfractions were most significant seven days postsurgery: natural killer cells decreased (P=0.003); T cells increased (P=0.008), with elevation in the CD4/CD8 ratio (P=0.003). B cells were largely unchanged at all time periods. Human leukocyte antigen-DR expression on monocytes was significantly less at 48 hours postsurgery (P < 0.001). All changes were reversed within three weeks of surgery. There were no differences when comparing laparoscopic-assisted resection with open surgery.


CONCLUSIONS
Both laparoscopic-assisted resection and open surgery affect the immune response. It would appear that laparoscopic-assisted resection does not have an immunologic advantage over open surgery in patients with colorectal cancer.
Department of Surgery, Prince of Wales Hospital and Chinese University Hong Kong, Shatin, New Territories.
P M
PM
Hewitt
S M
SM
Ip
S P
SP
Kwok
S S
SS
Somers
K
K
Li
K L
KL
Leung
W Y
WY
Lau
A K
AK
Li
D000328:Adult; D000368:Aged; D003082:Colectomy / Q000379:methods*; D015179:Colorectal Neoplasms / Q000601:surgery*; D005260:Female; D006098:Granulocytes; D006801:Humans; D007111:Immunity, Cellular; D015850:Interleukin-6 / Q000097:blood; D007694:Killer Cells, Natural; D010535:Laparoscopy; D016131:Lymphocyte Subsets; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies
D015850:Interleukin-6