The Sylvester Comprehensive Cancer Center at the University of Miami Miller School of Medicine, along with UM's Division of Comparative Pathology, which specializes in wildlife, confirmed the diagnosis.
Doctors chose a plan for treatment that has been most effective in humans.
"Peanut has handled this process with remarkable strength and fortitude," Chatfield said. "We have learned a great deal in the process and endeavored to provide Peanut with state-of-the-art care and the best possible chance at long term survival."
Peanut and her twin, Pumpkin, will celebrate their birthday on Dec. 2 with orangutan-friendly cakes. The park also will serve cake to guests and hand out lime green ribbons for lymphoma awareness. A portion of the day's admission also will be donated to the cancer center involved in the ape's treatment.