Mally Mall's slated to begin his 33-month prison term next week, but he'd like a little more time before he has to check in ... because he says he needs to undergo a medical procedure first.
According to new legal docs, obtained by TMZ ... the hip-hop producer -- who pled guilty in late 2019 to running an illegal prostitution service out of Las Vegas -- has discovered a mass on his thigh that will require a CT scan and biopsy to determine if it's cancerous.
Mall says the mass will need to be removed in the next month or so whether it's malignant or not, so he's asking the judge to push his August 13 date to surrender to the Bureau of Prisons back 3 months ... to November 12.
There's more though -- according to the docs ... after Mall received his 33-month sentence in May, he was designated to serve his time in a medium-security facility, which he calls "unexpected."
So, along with using the next 3 months to resolve medical issues ... Mall also says he needs some extra time to seek a potential re-designation to another prison.
The judge has not yet made a decision ... stay tuned.