A response from someone away back in September "I have just returned from a cruise on the Grand Princess with my dad who had to have oxygen constantly. We sailed from Southampton and flew back from Rome.Dad spent over £3000 to buy a portable oxygen concentrator which has a battery life of 10-12 hours which Dad used on trips off the ship. We took oxygen cylinders hired from omega oxygen (details provided by Princess) to use on board. We met Bill Quantrill in S'hampton and took the cylinders on board. They were stored in the hold as only one cylinder allowed in the cabin at any time. We flew with BA who would only allow 5 cylinders, which seems daft as they come in a case for 6, so we had to remove 1. I think they thought we were bringing 5 cases!! There is no charge to carry oxygen but it cost us £220 for 12 days including delivery and collection.Each cruise line may have different suppliers so contact whoever you booked with. Also British Lung Foundation has a lot of useful info.".
Many thanks, the information is very helpful.
Most probably can but you will need to raise this as a special requirement and no doubt there could be extra charges. Maybe someone who reads these questions knows more about this but yes it can be catered for.