Can bactroban cream be used on cyst?

I have a cyst on my intergluteal cleft (butt crack) and since it was not badly infected, my doctor gave me bactroban to put on it every 8 hours (3 times a day) for 10 days.

He also told me to continue the treatment for those 10 days, even if the cyst gets better or disappears after 3-4 days.