The other concern is his immune system. He is starting to have signs of improvement but that is only in relative terms and every treatment cycle will cause a fresh drop in resistance. We were very careful to plan our trip for the few days between when the toxins would begin to lessen and his immune system would begin to crash. Fortunately that happened to coincide with his birthday.
Even though we picked the optimal time, precautions still need to be taken. His immune system is still very, very weak so we are wearing masks anytime we are in the same room. I am also being careful to wear gloves anytime I need to handle anything he's touched to avoid exposure to second-hand chemo. It is possible that we are being overly cautious but the risks on both sides are so great that we feel it's better safe than sorry.