High incidence combination of multiple primary malignant tumors of the digestive system

Table 1 Clinical characteristics of multiple primary cancers patients. Clinical characteristics of patients with metachronous and synchronous multiple primary cancers

Clinical variable	Metachronous multiple primary cancers (n = 1687, 88.2%)	Synchronous multiple primary cancers (n = 224, 11.8%)	Total (n = 1902)	P value
Sex				< 0.0011
Male	562 (33.5%)	119 (53.1%)	681 (35.8%)
Female	1116 (66.5%)	105 (46.9%)	1221 (64.2%)
Age				0.3772
Mean (SD)	60.5 (11.7)	59.8 (11.8)	60.5 (11.7)
Rang	22.0-90.0	24.0-88.0	22.0-90.0

¹chi-squared test.

²t-test.

Table 2 Combination of non-uterine cancer and non-uterine cancer

	Cervix	Vagina	Ovary
Cervix	0	2	5
Vagina	3	0	0
Fallopian tube	1	0	1
Ovary	1	0	0

The row represents the first primary cancer and the column represents the second primary cancer.