using System;
using System.Linq;
using System.Text.RegularExpressions;

public class Test
{
	public static void Main()
	{
		string mainstr = "NONSALE_REVENUE,SALE_REVENUE";
		string result = Regex.Replace(mainstr, @"(?<![^,])(?:NON)?SALE_REVENUE(?![^,])", "SUM($&)");
        Console.WriteLine(result);
	}
}