How long does it take to have Grade 111C from Grade 1

I have Grade 111C Papillary Serous with Clear Cells Adenocarcinoma.  

I've had the op to remove everything, finished the rounds of chemo (taxol, carbopltnol) and am three weeks away from completing the second round of RT (the scar was so big I had to have two lots of sessions of RT). A long haul. My diagnosis was 30th December 2008!

I would really like to know how long ago I had the cancer before diagnosis of it at Grade 111C.  When did it begin? Months before?Years? When did it develop from  0 to Grade 1, then to Grade 11 - and how long or short a time does it take to become Grage 111C? What studies have been done on this progression and these timescales?

I had the syptoms (symptoms) for 6 months (bleeding and discharge) before the histeroscopy diagnosed the cancer and its stage.
Could I have had Grade 11, for example, six months before Grade 111C?

Thank you.