shingles with mantle cell

Just wondering if anyone has developed Shingles with Mantle cell. My mother was diagnosed over a year ago now with MCL she is currently on watch and wait (no treatment yet). Over the weekend she developed what the doctors say is shingles and put her on anti-biotics.  I was curious if this is common or if there are any complications to expect with a already weakened immune system. Thanks in advance for any input given..