A Systematic Review and Meta-analysis on the Occurrence of Biomarker Mutation in Colorectal Cancer among the Asian Population

Table 4

Subgroup analysis. Prevalence of BRAF gene mutation of patients with colorectal cancer stratified by study location.

Subgroup	No. of Studies	Prevalence (%)	95% CI	(%)		Heterogeneity test
						DF
India	4	11.7	0.062-0.210	73.69	11.401	3	0.010
China	7	4.0	0.025-0.063	93.42	91.205	6	0.001
Iran	3	4.7	0.004-0.403	96.16	52.129	2	0.001
Taiwan	1	1.1	0.003-0.043	NA	NA	NA	NA
Japan	5	6.9	0.044-0.107	55.86	9.062	4	0.060
Thailand	1	1.9	0.005-0.071	NA	NA	NA	NA
South Korea	1	3.3	0.011-0.096	NA	NA	NA	NA
Singapore	1	11.4	0.048-0.245	NA	NA	NA	NA
Vietnam	1	2.6	0.010-0.068	NA	NA	NA	NA
Israel	2	9.8	0.025-0.316	96.90	32.271	1	0.001
Saudi Arabia	1	2.2	0.014-0.035	NA	NA	NA	NA
Indonesia	1	14.0	0.064-0.278	NA	NA	NA	NA
Malaysia	1	2.3	0.003-0.144	NA	NA	NA	NA
Overall	29	5.6	0.039-0.080	94.00	466.942	28	0.001
BRAF subgroup by period of study conduct
2010 and below	8	5.6	0.020-0.146	96.45	196.928	7	0.001
After 2010	17	5.4	0.037-0.077	91.27	183.302	16	0.001
BRAF subgroup by tumour stage
Early tumour stage^1	10	40.1	0.293-0.518	62.297	62.297	9	0.005
Late tumour stage^2	10	59.9	0.482-0.707	95.59	62.297	9	0.005
BRAF subgroup by tumour location
Colon	10	67.9	0.577-0.766	54.421	19.746	9	0.020
Rectum	10	32.1	0.234-0.423	54.421	19.746	9	0.020
BRAF subgroup by tumour grade
Poor	11	30.4	0.189-0.450	88.066	83.794	10	0.001
Moderate	11	56.3	0.432-0.686	86.413	73.599	10	0.001
Well	11	10.2	0.056–0.179	69.996	33.329	10	0.001

¹Implies stages 1 and 2; ²implies stages 3 and 4.