Case insensitive search with location block

The location block is set with the tilde/asterisk modifier for case insensitive search as:

location ~* /RPNNode {
root /usr/share/nginx/html;
index index.html index.htm;
}

Then, localhost/RPNNode serves the web page as desired, but localhost/rpnnode fails as does other variations of capitalization (RPNNODE, RpnNode, etc.)

How can the location block be specified to find various case insensitive urls?