Cameron Mathison, a television star likely best known for his long-running role on All My Children, has been diagnosed with kidney cancer.

The actor 00 who currently hosts the Hallmark Channel morning talk show "Home and Family" -- announced the unfortunate news on Instagram Tuesday.

Although he explained that phyiscians believe his tumor has been growing for a "minimum 10 years," he said he's "optimistic" about his recovery.

Alongside a photo of his family, this is how Mathison opened his announcement:

"I have a health situation that I want to share with you all.

"There are many reasons I love social media, staying connected with you all, sharing fun experiences... well this time I'm asking for your help.

"About a month ago, I had an MRI for some gut issues I've been having, and during that MRI they found a tumor on my right kidney.

"It's consistent with Renal Cell Carcinoma ... or kidney cancer. The good news is that it hasn't spread to any other organs."

Mathison also is host of Entertainment Tonight and appeared on over 1,000 episodes of All My Children from 1998 through 2011.

He once appeared as a contestant on Dancing with the Stars.

Added the star in regard to his health and his prognosis:

"They say my healthy lifestyle and diet has no doubt helped keep it from growing and spreading to other areas, as doctors think it's been growing in me for minimum 10 years.

"I am extremely lucky that we found it early.

"Thank you to my longtime friend and urologist @jon_giddens who has helped me tremendously through this process."

This is the photo Mathison used alongside his revealing caption:

Mathison went on to thank his wife, Vanessa, and their two children, Leila, 13, and Lucas, 16.

"Vanessa, Lucas and Leila have been absolutely amazing with their love and support," he wrote. "As have my mom, dad, brother, and everyone at Home and Family, Hallmark, and ET."

Mathison proceeded to ask for support from his followers, as he will be undergoing surgery on Thursday.

"My surgery is scheduled on September 12th," he said.

"I was hoping to receive positive thoughts, prayers, or whatever you feel comfortable with, on 9/12 (my surgery is at 1pm PST) I announced this on @homeandfamilytv yesterday, and wanted to make sure I posted about it here as well."

Mathison concluded as follows:

"Feeling very grateful and optimistic!! #thankyou yes."

In response to the news, a number of stars with whom Mathison has worked expressed their condolences.

Candace Cameron Bure wrote: "Absolutely praying for you Cameron, and over the doctors and nurses during your surgery as well as your family."

Lacey Chabert: "Lifting you up in prayer! All my love to you and your family."

Ali Fedotowsky: "We love you Cameron. And we are all here for you."

We send our very best wishes to Cameron Mathison.

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