Suggest Treatment For Metastatic Colon Cancer

Hi, My husband had surgery in May for colon cancer with mets in the liver, two small spots which were cut out. They got all the cancer. He also, had tongue cancer at the same time, which he had surgery for in June. Getting ready to start radiation and chemo next week. He has been told he does not need treatment for the colon, that they treat the colon shortly after surgery and it is to late to do anything for the colon. He will be getting radiation and Chemo (Cisplatin) next week. Will this help control the cancer cells since the colon cancer was in the liver which would be in the blood stream. Or, is there nothing else that can be done unless it comes back. Thank you