assuming there is no great likelihood of a problem while your away, insurance will be very difficult (try allclear for quotes), so ensure you have a GHIC card which will allow access to Spanish health system. I know Tenerife has a public hospital in Los Cristianos area , which is in main tourist area, so easily accesible if necessary.

Cruises are always difficulty because of potential enormous costs of air lifting/diversion (I know this as am just about to go on one awaiting diagnosis of the severity of my bowel cancer. Annual insurance just run out, can't get insured as still undiagnosed , so going anyway)