Does Prolonged Use Of Vagifem Pess Cause Endometril Thickening?

I am using Vagifem Pess ands have been for ten years ,i have had ultrasound i.e. Transabdominal and endovaginal scanning performed. and my GP has told me the result is a slightly thickened endometrium and fluid . Am i heading for cancer my GP says will have another one in 10-12 months I also use Vagifem Pess can this cause this ? I am 74 years of age.Post menopause ? Regards von