Ghersa Family of Pre 50 S Trieste Italy

I was born in Rovigno when it still belonged to Italy to Francesco and Lucia Ghersa in 1942.That area is now a part of Croacia.I came to Canada in the early 1960's.I know I had an uncle who went to the U.S.A.I often wondered why my name was changed to Stambolic when I was a young boy about 13 yrs. old.I know on my mother's side there were Stamboli's but my name was always Ghersa like my father's until then.If anyone thinks they might know someone of that family or can shed some light on why my name might have been changed it would be interesting to know.Thanks