<s>[INST] my dad has lung cancer with mets to the brain. he just finished WBR last Monday and has been doing well til a few days ago. he started having periods of worsening confusion and is now vomiting again which he hasn t done in 4 wks. he also has some congestion and his sputum is white foamy. could this be dehydration or maybe just worsening of the tumors in the brain [/INST] Hi there, White foamy sputum is a non-specific sign but can be seen in conditions like heart failure and pneumonia. It may be seen in lung carcinoma as well. If it is not causing any problems, I'll not worry too much about it. Most important for him is symptomatic relief and palliative care. Try to get in touch with local palliative care team and get him medication for vomiting etc. Does he look deny Chat Doctor?  </s>