POLE ultra-mutated endometrial cancer and immunotherapy

It is my understanding that if a cancer has high mutation burden (like lung, melanoma) they are better candidates for immunotherapies. As far as I know ovarian cancer is a low mutation burden type of cancer and hence typically may have limitations in targeted therapies. Here is an article discussing that.  

Up until now I have only seen the presence of Micro Satellite Instability (MSI) being discussed as an indication of whether or not immunotherapies would work for endometrial cancer patients. I found out that there is another group. If the genomic profiling of your tumour has POLE exonuclease domain mutations (10% of the EC patients have this) and you are experiencing a recurrence, it seems you would be a good candidate for immunotherapy. Here are a few papers.. If you have the POLE mutation please check with your doctor to see if you qualify for an immunotherapy. 

https://www.ncbi.nlm.nih.gov/pubmed/27362548

https://www.ncbi.nlm.nih.gov/pubmed/28427513

https://www.sciencedirect.com/science/article/pii/S0959804917311462