Suggest Remedy For Lack Of Appetite In A Person With Prostate Cancer

My father in law has advanced stage of prostate cancer and is seeing an Oncologist of course, but I m concerned about his nutritional health. He has less appetite, has lost 10 lbs. in last month. How can we help him with nutrition, as much as possible? We realize this might be part of his decline, but wonder if there s more to do.