Chicago Teachers Union President Karen Lewis is in the hospital recovering from a stroke she suffered last week, she told the Chicago Sun-Times Tuesday.

The stroke Thursday was in an area of the brain where Lewis had a tumor removed in October 2014 when she was diagnosed with an aggressive brain cancer.

“Yeah, I had a stroke,” Lewis confirmed from Northwestern Memorial Hospital.

“I’m going to be OK,” Lewis added by telephone. “They’re going to have me in working order soon.”

She said she’d need rehab to strengthen her weakened left side, and hoped to start therapy soon at Chicago’s AbilityLab. And she joked that the view from her hospital room wasn’t as good as “the last time.”

Lewis’ cancer diagnosis in 2014 derailed a likely run for mayor; she underwent surgery even as her supporters were collecting signatures to get her on the ballot. Lewis instead threw her support to Jesus “Chuy” Garcia, who lost after forcing Mayor Rahm Emanuel into a runoff.

She called the stroke — which she described on Facebook as “small and annoying” — “a minor setback in my recovery from brain cancer.”

The risks of a stroke, which occurs when blood flow to a part of the brain is cut off, increase for people who’ve had brain tumors, either from the tumors themselves or from side effects of treatments, said Dr. Michael Schneck, a neurologist at Loyola University Medical Center in Maywood.

Aggressive treatments of Lewis’ glioblastoma — such as certain chemotherapy agents or radiation — could have affected blood vessels near the tumor site or increased her risk of blood clots, Schneck said, but “with aggressive care you can extend function, and have a good quality of life for a longer period of time.”

“She’s already beaten the odds,” he continued. “She’s survived three years.”

Ald. Susan Sadlowski-Garza (10th), one of the CTU’s closest City Council allies, was moved to tears when she learned about Lewis’ latest health setback.

“Oh, God. I just hope she’s OK. She’s amazing. Her heart is so in this job. Sometimes she just forgets about herself. I’ve seen it over and over. I just hope she’s OK. That’s what I pray for,” said the alderman, a former school counselor. “Since she got ill two years ago, she has been working and pushing for Chicago teachers and staff and the children to make sure they get what they deserve. Her drive and her passion is amazing.”

Sadlowski-Garza said she and Lewis and their husbands had dinner about a week ago at a restaurant in the 10th Ward.

“People were coming up to her and saying, ‘Thank you so much for caring about my kids,’” Sadlowski-Garza said.

Emanuel feuded for years with Lewis, who took her members out on strike in 2012 — and got the better end of the deal when the strike was over — and was poised to challenge him before falling ill. But since her diagnosis, the two adversaries have developed a mutual respect for one another.

Emanuel called her Tuesday morning, saying, “I sent her some matzo ball soup from Manny’s and I said, ‘I can’t vouch for the ingredients, but it’s worked for the last 400 years. Get well soon.’

“She has incredible strengths, and she sounds strong and I said, ‘We need you back on the field here, making sure that everybody stays focused and I hope that you recover soon.'”

Lewis confirmed the call and said she responded to the mayor’s “What do you need?” request with, “Flowers. . . . And let’s talk some s—.”

Chicago Federation of Labor President Jorge Ramirez marveled at Lewis’ ability to soldier on.

“Karen is always present in the moment. I’ve asked in the past, ‘What keeps you going?’ And she’s like, ‘I’m not done doing what I want to do. I’m not done moving the needle,’ ” said Ramirez, chairman of the labor-heavy investor group that recently purchased the Chicago Sun-Times.

“She’s not the type of person who feels sorry for herself. She’s the type of person who says, ‘Hey, I’ve got another day today. What am I gonna do with it?’ She’s been through the ringer. I’ll bet we don’t know the half of it because she’s not the kind to sit there and bellyache.”