Former Castle Actress Susan Sullivan Diagnosed with Lung Cancer: 'Healing Process Is a Struggle'

Susan Sullivan is sharing her ongoing struggles with lung cancer.

On Tuesday, the former Falcon Crest and Castle cast member, revealed on X that she'd been diagnosed with lung cancer and had undergone surgery.

"Thanks for all the lovely comments and concerns. I had lung cancer," the actress, 80, wrote to her followers on X. "The surgery was successful. The healing process is a struggle. Thanks glad you’re out there!"

Earlier in the week Sullivan shared a photo of herself in the hospital on X. "Life‘s surprising little turns try to be ready for them with humor and hope. On we go," she captioned the photo.

In the photo Sullivan, who did not disclose any further details on her diagnosis, is wearing a yellow mask and a hospital gown, and is holding an IV pole. The post received almost 400 comments from her fans.

"I hope you'll be back, to new, asap! I've always loved any performance you've given us. My favorite, will be, Castle's Mom. She was a delight! I loved MARTHA! I wish you all the best," one X user replied.

“Thinking of you wishing you a speedy recovery Susan. XO,” commented Kristian Alfonso, who starred in Falcon Crest with Sullivan.

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Sullivan is best known for her roles in numerous soap operas including Lenore Curtin Delaney on the NBC daytime soap opera Another World. In 2009, Sullivan joined the Castle team where she played the mother of Nathan Fillion.