Prognostic and clinicopathological significance of circulating tumor cells detected by RT-PCR in non-metastatic colorectal cancer: a meta-analysis and systematic review

Table 3

Results of subgroup analyses on OS

Variables	HR[95%CI]	Number	I²	P^d
Year > median^a
Yes	3.65[2.49–5.36]	6	0.00%	0.578
No	2.44[1.19–4.99]	7	72.90%	0.001
Country
East Asia	3.39[2.27–5.05]	10	46.50%	0.051
Non-East Asia	2.10[0.52–8.54]	3	74.50%	0.02
Marker
Single	2.72[1.48–5.00]	9	66.80%	0.002
Multiple	3.77[2.62–5.43]	4	0.00%	0.799
Sampling time point
Pre-op	3.65[2.49–5.36]	6	0.00%	0.578
Intra/post-op	2.44[1.19–4.99]	7	72.90%	0.001
Patient no. > median^b
Yes	3.45[2.57–4.65]	6	0.00%	0.801
No	2.59[1.08–6.22]	7	74.20%	0.001
Detection rate > mean^c
Yes	1.57[0.42–5.79]	4	74.10%	0.009
No	3.71[2.84–4.85]	9	0.00%	0.796
Quality of study
Low	4.06[1.64–10.05]	2	0.00%	0.384
High	2.95[1.87–4.65]	11	61.50%	0.004
Overall	3.07[2.05–4.62]	13	55.70%	0.008

NOTE: ^aThe median year for OS was 2012

^bThe median patient no. for OS was 103

^cThe mean detection rate for OS was 38.12%

^dTwo-tailed P value of tests for heterogeneity