APC, KRAS, PIK3CA or TP53 mutations were detected in the three participants with colorectal cancers; KRAS and TP53 mutations were detected in the participant with pancreatic cancer; a TP53 mutation was diagnosed in the participant with breast cancer; and TP53 and KRAS mutations were detected in the participant with lung cancer. The gene discussed is PIK3CA; the disease is colorectal cancer.