Former President Joe Biden has started radiation therapy as part of his ongoing treatment for prostate cancer, a spokesperson confirmed to media outlets.

“President Biden is currently receiving radiation and hormone therapy as part of his prostate cancer treatment plan,” the spokesperson said, according to NBC News, the first to report the development.

Biden turns 83 in November.

In May, his office announced that he had been diagnosed with an aggressive form of prostate cancer, which had metastasized to his bones.