The primary and recurrent tumors in Group A did not show structural alterations in the p16 , p15 or CDK4 genes , whereas homozygous codeletion of p16 and p15 was observed in both primary and recurrent tumors in Group B .
the primary and recurrent tumors in group a did not show structural alterations in the p16 , p15 or cdk4 genes , whereas homozygous codeletion of p16 and p15 was observed in both primary and recurrent tumors in group b .
O O O B-tissue I-tissue O O O O O O O O O O O O O O O O O O O O O B-DNA_domain_or_region O B-DNA_domain_or_region O O O O B-tissue O B-tissue I-tissue O O O O