The results of familial population analysis of stomach cancer and mult
iple primary malignant tumors (MPMTs) are presented. The data obtained
provide evidence for the multifactorial nature of stomach cancer. Her
editary factors accounted for 32% of the general predisposition of ind
ividuals to stomach cancer. The age-related character of stomach cance
r was established. Genetic heterogeneity of this tumor is suggested by
the data obtained. Significant genetic commonness in the inheritance
of stomach, colon, Genetic Analysis and Prognosis for Malignant Tumors
in breast, endometrial, and ovarian cancer in families of MPMT patien
ts was demonstrated on the basis of the obtained genetic correlations
between tumor types in MPMT patients and solitary tumors in members of
their families. The greatest genetic load was shown for families of M
PMT patients, as compared with families of patients with solitary tumo
rs, the coefficient of MPMT inheritance being equal to 77.4%. The data
on the genetic character of stomach cancer and MPMT formed the basis
for the identification of criteria for developing methodological appro
aches to the screening of individuals from risk groups to facilitate e
arly diagnosis and prevention of cancer.