#!/usr/bin/perl -w

use strict;
#putting the line in question into $_ for this example.
$_ = "Cell ID for Last Cell: MCC: 310  MNC: 64  LAC: x'44D  CI: x'503E";

#create our hash of 'site codes' => 'text to print'
my %cells = ('207B' => 'Miami',
             '432F' => 'Buffalo',
             '443R' => 'Whatever you want for cell site 443R',
             '503E' => 'Portland, OR'
            );

if (/CI: x'(\w+)$/) {
    print "Cell site is $cells{$1}.\n";
}