Agreed, the differences in symptoms among cases is strange, and treating ANs is not settled science. It seems the location of the tumor, such as a position adjacent to the cochlea or facial nerve, influences symptoms as much as size. However, other variables such as diet, exercise, personality, etc. are studied less, probably due to the fact that it is a rare condition, hence, less funding for studies and trials. There are a number people, on this site and elsewhere, with tiny vestibular schwannomas, e.g. under 6 mm in diameter, that have expressed difficulties leading a normal life, while at least one that I am aware of, had the tumor pressing against the brainstem when diagnosed, and was put on watch and wait, with few discernible symptoms. The converse of that is also true, smaller tumors fewer symptoms, larger tumors, more problems. It's all individual. For me, changes in tumor size [from 6 mm to 13-15 mm (conflicting feedback from last MRI) in the last 3.5 years] have led to a disquieting increase in symptoms, despite maintaining an incredibly healthy diet and active exercise lifestyle for many years prior to and since diagnosis. I recall reading somewhere that having a stressful career may have some correlation with VS, though can not recall where that may be sourced. There is simply too much that we still do not understand about this insidious condition, and which treatments to use, and when to use them. IMHO, one is fortunate to be able to continue to be on watch and wait, with few symptoms.