I have to imagine that given the right mixture of hormones, anyone could experience gigantomastia. Perhaps your local pharmacy will have the mix in the future for over the counter purchase.
The problem might be that every body is so individual, that makes it pure coincidence to have the right mixture.
Agreed, it may not be a one size fits all problem, but some years back, a princess here explained the exacting chemistry changes that take place in creating gigantomastia, which she herself was trying to mimic with particular herbs and OTC supplements while encouraging lactation. Over the span of 4 years, she had gone from a loose G cup to a O cup, so I think she was on to something.
Not her, but girls can wish.