Keyhole laparoscopic or open surgery for rectal cancer

Colorectal (large bowel) cancer including rectal cancer is the third most common cause of cancer deaths in the western world. The risk of developing rectal cancer increases with age and is most common in people around 70 years of age. The treatment consists of complete surgical resection of the tumour and surrounding tissue by a technique called total mesorectal excision (TME), sometimes combined with chemotherapy and radiotherapy. This surgery can be performed by either normal open abdominal surgery with a large incision or by keyhole laparoscopic surgery with several small incisions for the instruments and camera. For colon cancer, laparoscopic surgery is proven to result in faster postoperative recovery, fewer complications and better cosmetic results. These results are expected to be equal for rectal surgery. However, surgery for rectal cancer is technically more difficult than for colon cancer due to the location deeper in the pelvis and close to important nerves. Therefore a complete and safe resection of the tumour should be guaranteed, this is important to reduce the risk of recurrence of the tumour and could be tested by assessing recurrence rates and patient survival in the long term.

In this updated review, we have assessed all randomised studies of laparoscopic and open TME for rectal cancer, to compare and combine their results. We included 14 trials reporting on a total of 3528 patients undergoing rectal cancer surgery. In 14.5% of those having laparoscopic surgery needed conversion to open surgery by a large incision in the abdomen due to difficulties or problems during the procedure.

There is currently moderate quality evidence that laparoscopic total mesorectal excision (LTME) has similar effects to open TME (OTME) on long term survival outcomes for the treatment of rectal cancer. The estimated effect was imprecise and further research could impact on our confidence int this result. There is moderate quality evidence that it leads to better short-term post-surgical outcomes in terms of length of hospital stay. We found that pain was lower in the LTME group and that resumption of diet was better. We did not find clear evidence of a difference in quality of life between the two groups, but costs were higher for LTME. We await long-term data from a number of ongoing and recently completed studies to contribute to our understanding of the effects of these surgical approaches on long-term disease free, overall survival and local recurrence.

Authors' conclusions: 

We have found moderate quality evidence that laparoscopic total mesorectal excision (TME) has similar effects to open TME on long term survival outcomes for the treatment of rectal cancer. The quality of the evidence was downgraded due to imprecision and further research could impact on our confidence in this result. There is moderate quality evidence that it leads to better short-term post-surgical outcomes in terms of recovery for non-locally advanced rectal cancer. Currently results are consistent in showing a similar disease-free survival and overall survival, and for recurrences after at least three years and up to 10 years, although due to imprecision we cannot rule out superiority of either approach. We await long-term data from a number of ongoing and recently completed studies to contribute to a more robust analysis of long-term disease free, overall survival and local recurrence.

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Background: 

Colorectal cancer including rectal cancer is the third most common cause of cancer deaths in the western world. For colon carcinoma, laparoscopic surgery is proven to result in faster postoperative recovery, fewer complications and better cosmetic results with equal oncologic results. These short-term benefits are expected to be similar for laparoscopic rectal cancer surgery. However, the oncological safety of laparoscopic surgery for rectal cancer remained controversial due to the lack of definitive long-term results. Thus, the expected short-term benefits can only be of interest when oncological results are at least equal.

Objectives: 

To evaluate the differences in short- and long-term results after elective laparoscopic total mesorectal excision (LTME) for the resection of rectal cancer compared with open total mesorectal excision (OTME).

Search strategy: 

We searched the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library 2013, Issue 2), MEDLINE (January 1990 to February 2013), EMBASE (January 1990 to February 2013), ClinicalTrials.gov (February 2013) and Current Controlled Trials (February 2013). We handsearched the reference lists of the included articles for missed studies.

Selection criteria: 

Only randomised controlled trials (RCTs) comparing LTME and OTME, reporting at least one of our outcome measures, was considered for inclusion.

Data collection and analysis: 

Two authors independently assessed study quality according to the CONSORT statement, and resolved disagreements by discussion. We rated the quality of the evidence using GRADE methods.

Main results: 

We identified 45 references out of 953 search results, of which 14 studies met the inclusion criteria involving 3528 rectal cancer patients. We did not consider the risk of bias of the included studies to have impacted on the quality of the evidence. Data were analysed according to an intention-to-treat principle with a mean conversion rate of 14.5% (range 0% to 35%) in the laparoscopic group.
There was moderate quality evidence that laparoscopic and open TME had similar effects on five-year disease-free survival (OR 1.02; 95% CI 0.76 to1.38, 4 studies, N = 943). The estimated effects of laparoscopic and open TME on local recurrence and overall survival were similar, although confidence intervals were wide, both with moderate quality evidence (local recurrence: OR 0.89; 95% CI 0.57 to1.39 and overall survival rate: OR 1.15; 95% CI 0.87 to1.52). There was moderate to high quality evidence that the number of resected lymph nodes and surgical margins were similar between the two groups.
For the short-term results, length of hospital stay was reduced by two days (95% CI -3.22 to -1.10), moderate quality evidence), and the time to first defecation was shorter in the LTME group (-0.86 days; 95% CI -1.17 to -0.54). There was moderate quality evidence that 30 days morbidity were similar in both groups (OR 0.94; 95% CI 0.8 to 1.1). There were fewer wound infections (OR 0.68; 95% CI 0.50 to 0.93) and fewer bleeding complications (OR 0.30; 95% CI 0.10 to 0.93) in the LTME group.
There was no clear evidence of any differences in quality of life after LTME or OTME regarding functional recovery, bladder and sexual function. The costs were higher for LTME with differences up to GBP 2000 for direct costs only.