Good news in John Andretti's cancer fight

Jim Ayello | IndyStar

Show Caption Hide Caption John Andretti battles cancer Michael and Jarett Andretti speak about John Andretti's fight with colon cancer, during a press conference at Andretti Motorsports headquarters, Indianapolis, Thursday, May 4, 2017.

INDIANAPOLIS – John Andretti delivered some good news Wednesday regarding his fight against Stage 4 colon cancer. The former IndyCar and NASCAR driver revealed on Twitter that his spleen and gallbladder were cancer free.

"Good news, the spleen & gall bladder were clean," Andretti's tweet said. "Next stop is a scan & consult with Dr. Iannitti in 1 month. Then back to chemo for 3 months."

Andretti, a self-described private person, elected to make his cancer fight public a couple of months ago in an effort to encourage more people to have preventative screenings.

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He created the hashtag #CheckIt4Andretti on Twitter so that others could let him know when they were getting screened.

Since doing that, he has been flooded with messages of men and women letting him know when they are going to #CheckIt4Andretti.

It's not just John promoting the message either. Friends and family have gotten in on the act. The Indy cars of team owner Michael Andretti's — John's cousin — began promoting the message on their liveries at the Indianapolis 500 and continued to do so throughout the season.

Andretti continues to stay positive throughout his fight. He underwent surgery June 20, saying on Twitter: "Today Dr. Iannitti performs his magic to allow me to become an much older man! He is BA and Italian. #greatcombination."

Two days later, he posted: "Home today from the hospital. Ablation of 2 spots on liver, removed spleen and gallbladder. Doing well. #CheckIt4Andretti."

With 11 incisions, I think I probably look like "The Godfather" after he was shot! Be sure to schedule your colonoscopy. #CheckIt4Andretti — John Andretti (@John_Andretti) June 23, 2017

Follow IndyStar Motor Sports Insider Jim Ayello on Twitter and Instagram: @jimayello.