The phrase 'became lost to' is a correct and usable piece of written English.
You can use it when speaking about someone who is no longer present or no longer visible, especially when there is an element of tragedy or mystery associated with their disappearance. For example: The family pet became lost to them after they moved away, never to be seen again.
True, there was a welter of emotion to be countenanced, but I was happy to be doing it and became lost to the outside world.
Left to languish, the ballroom became lost to time, gathering a thick layer of dust and becoming a sort of grand attic for the hotel.
During the study period 17 patients became lost to follow-up.
During the follow-up time of the cohort, 17 patients became lost to follow-up.
During the study period, 17 patients became lost to follow-up (Fig. 1).
For this analysis, we additionally excluded women who became lost to follow-up, either prior to or after delivery.
Even the things that are sent to help us end up being caught in such a webby mass of unsought influences, unsuspected ramifications and counterintuitive consequences that the original benign impulse behind their invention becomes lost to history.
Don't hoard what seems good for a later place in the book, or for another book; give it, give it all, give it now... Anything you do not give freely and abundantly becomes lost to you".
There are a number of ways in which data could be missing: the subject is unable to provide it, or they withdraw, or become lost to follow-up.
When middle-class households move away from a migrant neighborhood, do they cut all ties with the old neighborhood and do their social, cultural and economic resources really become lost to it?
If we withdraw from reality's true nature - that it changes constantly and so do we - we become lost to ourselves, punished by our troubles and by their ineffective cure.
