Laparoscopic surgery for T4a tumours might be safe, whereas for T4b colon cancer requiring multivisceral resection (MVR) it should be applied with caution, these are the conclusion from a systematic review of literature by researchers from the Department of Surgery, Academic Medical Centre University of Amsterdam, The Netherlands. The paper, ‘Laparoscopic surgery for T4 colon cancer: a systematic review and meta-analysis’, was published in Surgical Endoscopy. The authors also noted that the current literature does not provide the definitive answer on oncological safety of minimally invasive surgery for locally advanced colon cancer.
In their review, the authors sought to ystematically review the currently available literature on laparoscopic surgery for T4 colon cancer, with regard to short- and long-term oncological outcomes, and to compare these with open surgery. All articles were considered eligible if containing original data on laparoscopic resection of T4 colon cancer. T4 stage referred to either clinical or pathological stage. The main out comes of the review were radicality of resection, postoperative morbidity and long-term oncological survival outcomes.
A total of 13 studies (23%) were included, three multicentre studies and ten single-centre studies. All studies together comprised 1,217 patients that received laparoscopic surgery and 1,357 that underwent open surgery. In all studies, converted patients were included in the laparoscopic group as intention to treat principle, and the conversion rates varied from 5.6 to 23%, with a pooled proportion of 0.11 (95% CI:0.09–0.14).
The report that postoperative (30-day, early) complication rates ranged from 7.7 to 30% in laparoscopic groups and from 21 to 49% in the open cohorts, mainly including anastomotic leakage, (intra-abdominal) abscess, ileus, urinary tract infection, and wound infection.
The pooled proportion of postoperative complications was 0.23 (95% CI: 0.19–0.27) for laparoscopy, and 0.35 (95% CI: 0.31–0.40) for open surgery, whilst poled postoperative mortality rates were 0.02 (95% CI: 0.01–0.04) and 0.03 (95% CI: 0.02–0.06), respectively. Meta-analysis of comparative studies reporting on postoperative complications revealed a risk ratio for laparoscopic versus open surgery of 0.65 for postoperative complications [95% CI: 0.55–0.77; p < 0.001, (heterogeneity: I2 0%, p=0.51)]. Adjuvant chemotherapy was applied in 55–100% of patients after laparoscopic surgery and in 37–80% after open resection.
Eleven studies reported on radicality of resection (R0) and the proportions of radical resections varied from 74 to 100% for laparoscopic surgery and from 76 to 100% in the open group. Pooled proportions were 0.96 (95% CI: 0.91–0.99) and 0.96 (95% CI: 0.90–0.98), respectively. Meta-analysis revealed no significant difference in radicality of resection between laparoscopic and open surgery (RR: 1.00 (95% CI: 0.98–1.01), p=0.80).
Using meta-analysis, the researchers found no statistically significant differences between laparoscopic and open surgery for any survival measure. For subgroup analyses of T4a stage, seven studies were selected of which six provided separate data for pT4a and in one additional study, pT4a was included in >80% in both the open and laparoscopic groups.
Pooled proportions of R0 resection of these studies were 0.94 (95% CI: 0.81–0.98) and 0.94 (95% CI: 0.82–0.98) after laparoscopic and open surgery, respectively (RR 1.00, 95% CI: 0.97–1.02, p=0.75 (I2=0%, p=0.99), 6 studies). Furthermore, no significant difference was found for any survival measure.
Considering T4b stage, five studies provided separate data and the pooled proportions of R0 resection of these studies were 0.91 (95% CI: 0.80–0.96) and 0.93 (95% CI: 0.80–0.98) after laparoscopic and open surgery, respectively (RR 0.99, 95% CI: 0.92–1.05, p=0.68 (I2=0%, p=0.69). Although in favour of open surgery, no significant differences were found for any survival measure.
The risk of developing a postoperative complication was significantly lower after laparoscopic surgery as compared to open surgery (p<0.001). However, they note that in five out of ten comparative studies reporting on postoperative complications, substantially more MVRs were performed in the open group, compared to the laparoscopic group. Therefore, they state that benefit of a laparoscopic approach for MVR might be limited, especially considering the fact that often large extraction incisions have to be made to remove the relatively large MVR specimens.
“Based on subgroup analysis, we cautiously conclude that laparoscopic surgery for T4a tumours might be safe, whereas it seems less appropriate for T4b tumours requiring multivisceral resection,” the authors conclude. “Laparoscopic resection of T4 colon cancer should probably only be performed in selected patients by experienced surgeons. These selection criteria and level of experience have to be defined more precisely in future studies.”
The article was edited from the original article, under the Creative Commons license.
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