84 - Freie Mitteilung
17. Mai 2019, 08:15 - 09:45, Bellavista 5, 6. OG
Prevalence of metastatic lateral lymph nodes in patients with low rectal cancer: A systematic review and meta-analysis
N. Christou, J. Meyer, C. Combescure, A. Balaphas, E. Liot, N. Buchs, F. Ris, Presenter: N. Christou (Geneva)
We performed a systematic review and meta-analysis to assess the prevalence of metastatic lateral lymph nodes in patients with low rectal cancer.
We searched MEDLINE, EMBASE and COCHRANE from inception until November the 19th, 2018 for studies reporting the prevalence of metastatic lateral lymph nodes (iliac, obturator and middle sacral nodes) among patients undergoing rectal surgery with lateral lymph node dissection. Pooled prevalence values were obtained by random effects models and robustness was tested by leave-one out sensitivity analyses. Heterogeneity was assessed using the Q-test, quantified based on I2 value and explored by subgroup analyses.
Our final analysis included 31 studies, comprising 7’599 patients. The pooled prevalence of metastatic lateral lymph nodes was 17.3% (95%CI : 14.6 to 20.5). The between studies variability (heterogeneity) was important (I2=89%). The pooled prevalence was however robust and varied between 16.6% and 17.9% according to leave-one out sensitivity analysis. The pooled prevalence of metastatic lymph nodes did not statistically differed when pooling only studies including patients who received neoadjuvant treatment or those including patients without neoadjuvant treatment (p=0.44). Meta-regression showed that the pooled prevalence was associated with the sample size of studies (p<0.05), as the prevalence decreased when the sample size increased.
The pooled prevalence of metastatic lateral lymph nodes was 17.3% among patients who underwent lateral lymph node dissection for low rectal cancer. Further studies are necessary to determine whether this finding could impact the effectiveness of therapeutic strategy (total mesorectal excision with systematic lateral lymph node dissection versus total mesorectal excision with radiochemotherapy).