Carbon nanoparticles useful as a lymph node tracer in colorectal cancer surgeries

Carbon nanoparticles (CNs) improve the detection of lymph nodes in colorectal cancer surgeries, reports a recent meta-analysis.

From the databases of PubMed, Embase, CENTRAL, Web of Science, Chinese Biological Medicine, CNKI, Wanfang, and Cqvip, researchers retrieved 17 randomized controlled trials that compared CNs with a blank control for lymph node (LN) dissection. The pooled sample included a total of 1,241 colorectal cancer patients, in 600 of whom CN had been used.

In all included studies, surgeries that used CNs retrieved a greater number of LNs per patient, with mean difference (MD) values ranging from 1.60 to 14.60. Quantitative synthesis found that this effect was statistically significant (weighted MD [WMD], 5.21, 95 percent confidence interval [CI], 4.14–6.29; p<0.00001).

In addition, the percentage of patients with retrieved LNs ≥12 was higher in the CN group by around 14 percent (p<0.0001).

CNs were also able to detect a significantly higher rate of metastatic LNs relative to controls (relative risk [RR], 1.56, 95 percent CI, 1.40–1.75; p<0.00001). Similarly, detection rates of micro (RR, 1.68, 95 percent CI, 1.38–2.04; p<0.00001) and micro metastatic (RR, 1.92, 95 percent CI, 1.26–2.92; p=0.002) LNs were significantly better when surgeries were conducted with CNs.

“To the best of our knowledge, this is the first systematic review and meta-analysis about the clinical application of CNs in lymphatic mapping during CRC surgeries,” the researchers said, however pointing out that, in general, there was a strong heterogeneity of evidence and that in some of the analyses, publication bias could not be ruled out.

“Further clinical trials involving more patients are needed to verify the benefits of CNs,” they added.