Miller's orthopedic spine surgeon, Dr. Hooman Melamed, tells ET, "It’s a preliminary diagnosis. The results are still pending a pathology report."
Burkitt Lymphoma, which is a non-Hodgkin lymphoma, is a form of cancer that affects the lymphatic system and starts in antibody-producing B cells, which are part of the immune system.
“People who have been diagnosed with this have a good prognosis," Dr. Melamed said. "We’ll know more details soon."
Dr. Melamed also discussed Miller's recent spinal cord surgery, telling ET that the outcome is "looking really good," and that he's "optimistic" about her recovery.
However, he said the former Dance Moms star is "not out of the woods yet."
"She will need another surgery in her spine but she has a lot more movement in her arms, legs and toes," he explained. "As of this morning, Abby was in much better spirits and as of just a few minutes ago she was sleeping."
Abby Lee Miller's Doctor Explains the 'Serious' Condition that 'Almost Undid' Her Gastric Sleeve Surgery (Excl
The 51-year-old reality star was rushed into surgery in the early hours of Tuesday morning after several days of suffering from "extreme pain in her back, arms and neck area," Dr. Melamed previously told ET after the operation.
Performing a CT scan, the doctor discovered a mass infection putting pressure on Miller’s spine. He rushed her into emergency surgery to remove the infected mass at around 1 a.m.
The doctor explained that, before the procedure, Miller "could not move" and that if she hadn't gone under the knife, "she could have died."
"Forget paralysis -- if she waited much longer she would’ve died from this,” Dr. Melamed said, adding that she may need additional surgeries in the future.
The cause of the infection that necessitated surgery remains unknown.
Dr. Michael Russo, who performed Miller's gastric sleeve surgery last year, told ET last week that he believes her severe back pain stems from hypothyroidism, which began when she stopped taking one of her thyroid medications.
"Her hypothyroidism got so severe she had an assortment of symptoms. Most dramatic is severe muscle and bone pain in her back, shoulders, arms and legs," Dr. Russo shared. "When Abby first went to the ER, she was almost unable to move [her] arms and legs and was having trouble getting out of bed. She had numbing and tingling in her hands and feet. She couldn't even hold a spoon in her hand."
Earlier this month, a source told ET that the reality star was taken from the halfway house via ambulance and admitted to a hospital in Long Beach for a back condition, which she has been dealing with for some time.