Histopathological evaluation of the cases first identified in the family (Subjects IV-4, 13,16, 17, 24) showed extensive, diffuse, poorly differentiated adenocarcinomas with SRC component eroding the mucosa and invading throughout the lamina propria, muscularis mucosae, submucosa and muscularis propria, further penetrating the subserosal connective tissue with invasion of the peritoneum and metastases in the regional lymph nodes. The gene discussed is SRC; the disease is adenocarcinoma.