I was tested for Lynch, but my dMMR is in the tumor only, so I don't have it. I am MSI-H, and thus an excellent candidate for immunotherapy. Clearly, if you are now NED you don't need it now, but it's good to know it's available.
When I was discussing this with the genetic counselor, she mentioned that women with Lynch may choose to have a prophylactic hysterectomy after childbearing is over, and I've also read this. Since I was 65 at the time, that is something I would have considered. I haven't seen any suggestion that women your age should do so, unless maybe you have already had a number of children and don't want more.
Have you spoken with a genetic counselor? If not, you ought to do so whether or not your results come back positive for Lynch. The fact that your sibling has CRC doesn't necessarily mean you both have Lynch. My sister had CRC, and I don't. Admittedly, we were older.
F, 64 at DX CRC Stage IV
3/17/18 blockage, r hemi
11 of 25 nodes,5 mesentery nodes
5mm liver met out
pT3 pN2b pM1
BRAF wild, KRAS G12D
7/18 CT NED
11/18 CT NED
12/18 MRI 5mm liver mass, 2 lymph nodes in porta hepatis
6/19 Multiphasic CT LNs normal, Liver stable
6/28/19 Pause Key, predisone for joint pain
7/31/19 Restart Key
9/19 CT stable
Pain: all fails but Celebrex
12/23/19 CT stable
5/19 MRI stable/NED