Assuming that all your variables are single key-value pairs, you can retrieve request parameters in a way similar to using CGI::params with this technique:

my $r = shift;  # or $r = Apache->request
my %params = $r->method eq 'POST' ? $r->content : $r->args;

Also take a look at Apache::Request, which has the same API as CGI.pm for extracting and setting request parameters but is significantly faster, since it's implemented in C.