I am asking the question for a male friend very active and healthy 60 yrs old. Symptoms started April 15 this year. Passed out for no reason, loss of appetite, hoarseness in voice, low bp 90/60, weakened physical ability, feeling of phlegm in throat Has had many test, MRI s blood, ear nose and throat screening. nothing found, has had symptoms for 3 months,with 2 ER visits. What should he be looking for?