Schlehuber announced the sad news on Twitter and Instagram Monday night with a screenshot of a note he had typed out on his phone.
"Hi everyone I have some news to share with you. Last night I got a call & went to the doctor with my family today. I was told I have cancer," he wrote. "I'm not posting this for sympathy but to raise awareness. Please go to regular check-ups & doctors appointments. Get tested & always be aware of how you feel."
He continued, writing that nothing tipped him off to the diagnoses aside from his check-up. "I FEEL perfectly healthy but that is not the case. I will beat this with the love & support from my family and close friends. Again, PLEASE get checked, it can save your life!" he said.
"Thank you for taking the time to read this. I love and appreciate all of you & your supportive words mean more now than ever. All my love to you, KEVIN," he concluded, adding a heart and praying hands emoji.
Schlehuber, 57, who made it to week 11 before being evicted from the house, was a fan- and houseguest-favorite on the show.
He has not said what type of cancer he was diagnosed with or what the doctor's prognosis is. Other than thanking those who have reached out to him following his announcement, he has not given any more information.
Many former contestants of the CBS show responded to his announcement offering their support.
"Stay strong brother! Keeping you and your family in my prayers!" wrote legendary Big Brother player Derrick Levasseur.
Stay strong brother! Keeping you and your family in my prayers! 🙏🏻— Derrick Levasseur (@DerrickL) October 23, 2018
"Sending lots of love to you and your family Kevin," wrote Ika Wong, who appeared on two of the show's Canadian seasons.
Sending lots of love to you and your family Kevin 💛🙏🏾— ika wong (@theikawong) October 23, 2018
Dominique Cooper, who appeared on Schlehuber's season, sent praying hands emojis.
🙏🏾🙏🏾🙏🏾🙏🏾🙏🏾🙏🏾🙏🏾— Dominique Cooper (@CDmAI) October 23, 2018
Christmas Abbott, who cast the sole vote to evict Schlehuber to take herself, Paul Abraham and Josh Martinez to the final three in season 19, left a lengthy comment on his Instagram.
"Kevin - this sucks right now and it's going to get worse before JT gets better but you are KEVIN!!!! I believe you are like my mother who kicked breast cancers ass. She refused to say she was a survivor because she is a thriver. That's you Kevin, a THRIVER and you're going to be that amazing Kevin we all know. Love you lots friend," she wrote.
Abraham, who came in runner-up to Martinez, also left a supportive comment. "I'm sorry to hear this Kevin, I know your positive spirit will get you through this. Sending love to you & the family," he commented.
Fans also immediately responded to the social media posts with sympathy.
"Sending so much love and prayers your way!! You got this Kevin, Stay strong and bust cancer's ass!" one fan wrote on Instagram.
"You got this! You have your Family & BB Family support!" another said.
"Sending love and prayers to you Kevin...you will BEAT this!" another wrote.0comments
"Praying for you and your family. I love seeing how the big brother family has come together to support you. You go this @bb19kevin," one fan said.
"I'm so sorry to hear about your news. Keep fighting," a user wrote.