Oncologic Results of Laparoscopic Versus
Conventional Open Surgery for Stage II or III
Left-Sided Colon Cancers
A Randomized Controlled Trial
A randomized controlled trial (RCT) is a type of scientific experiment most
commonly used in testing the efficacy or effectiveness of healthcare services
(such as medicine or nursing) or health technologies (such as
pharmaceuticals, medical devices or surgery).
3%
2%
5.5%
5%
4%
12%
21%
0.5%
38%
2%
4 stages of tumour size in colorectal cancer:
T1 : the tumour is only in the inner layer of
the bowel
T2 : the tumour has grown into the muscle
layer of the bowel wall
T3 : the tumour has grown into the outer
lining of the bowel wall or into organs or
body structures next to the bowel
T4 : into other parts of the bowel, other
organs or body structures near to the bowel
(such as the liver or small bowel), or the
tumour has broken through the membrane
covering the outside of the bowel (the
peritoneum)
3 possible stages : cancer cells in the lymph nodes
N0 : no lymph nodes containing cancer cells
N1 : 1 to 3 lymph nodes close to the bowel contain
cancer cells
N2 : cancer cells in 4 or more lymph nodes that are
further than 3cm away from the main tumour in the
bowel OR there are cancer cells in lymph nodes
connected to the main blood vessels around the
bowel
Two stages of cancer spread (metastasis):
M0 : cancer spread to other organs
M1 : cancer spread to other parts of the body
Stages of colorectal cancer
Stage 0 or carcinoma in situ (CIS):
cancer cells all contained within the lining of the bowel.
very little risk of any cancer cells having spread.
very unusual for bowel cancer to be diagnosed this early
Stage 1: cancer has grown through the inner lining of the
bowel, or into the muscle wall but no further. There is no cancer
in the lymph nodes (T1, N0, M0 or T2, N0, M0).
Stage 2:
Stage 2a : no cancer cells in the lymph nodes, but the cancer
has broken through the outer covering of the bowel (T3, N0, M0)
Stage 2b : cancer has grown through the outer covering of the
bowel wall and into tissues or organs (T4) next to the bowel.
But no lymph nodes are affected (N0) and the cancer has not
spread to another area of the body (M0).
Stage 3
Stage 3a : cancer is still in the inner layer of the bowel
wall or has grown into the muscle layer, and between 1
and 3 nearby lymph nodes contain cancer cells (T1, N1,
M0 or T2, N1, M0)
Stage 3b : cancer has grown through the bowel wall or
into surrounding body tissues or organs and between
1 and 3 nearby lymph nodes contain cancer cells (T3,
N1, M0 or T4, N1, M0)
Stage 3c : cancer can be any size, has spread to 4 or
more nearby lymph nodes, but there is no cancer
spread to any other part of the body (any T, N2, M0)
Stage 4: cancer has spread to other parts of the body
(such as the liver or lungs) through the lymphatic
system or bloodstream (any T, any N, M1).
Surgical Therapy
Left sided lesions: ligation of the inferior mesenteric
vessels or their branches.
Splenic flexure cancers and cancers high in the left
colon are often difficult to mobilise, particularly if they
are large.
Theoretically, anastomosis can be performed between
the proximal transverse colon and proximal sigmoid
colon, in reality this may be difficult and an
ileosigmoid anastomosis may be necessary.
Laparoscopic versus Open Resection
Laparoscopic colon resection: first described in 1991
Less pain, more raped recovery.
X early reports of recurrences at the site of port sites
Ortega, 1995: a port site recurrence rate of 1.2% in 504
patients
registered in The American Society of Colon and Rectal Surgeons database
Multiple RCTs in Europe, S. America, Asia, Australia and N. America
Results suggest LR takes longer to perform
Hospital stay
Pain and narcotic requirements
Cost
The evidence to date suggests that laparoscopic
colectomy is an acceptable alternative to open surgery
for colon cancer
The medial approach :
Division of the vascular pedicle first, followed by
mobilization of the mesentery toward the abdominal
wall, and finally freeing of the colon along the white
line of Toldt. This approach allows immediate
identification of the plane between the mesocolon
and the retroperitoneum and renders the dissection
fast and safe.
286 eligible patients
Randomization
143 allocated to
laparoscopic group
143 allocated to
open group
8 excluded from analysis
9 excluded from analysis
• 6 with metastatic disease
detected intra-operatively
• 2 withdrawn from study
• 7 with metastatic disease
detected intra-operatively
• 2 withdrawn from study
4 patients converted
•1 poor visualisation
• 1 massive bleeding
• 2 incomplete mobilisation
134 included in the intention-to-treat analysis
134 included in analysis
Intention to treat analysis
based on the initial treatment intent, not on the
treatment eventually administered.
to avoid the effects of crossover and drop-out, which
may break the randomization to the treatment groups
in a study.
Intention to treat analysis provides information about
the potential effects of treatment policy rather than
on the potential effects of specific treatment.
Conclusion
With regard to the surgical treatment for Stage II or III
left-sided colon cancers, the oncologic results for of
laparoscopic approach were similar to those of
traditional open surgery seeing that the extent of
tumour extirpation and the tumour recurrence rate
were the same in both methods.
Thank You