ST. PAUL, Minn. (WCCO/AP) — The day after collapsing during his State of the State speech, Gov. Mark Dayton revealed Tuesday he has been diagnosed with prostate cancer.

Dayton went to Mayo Clinic in Rochester Tuesday afternoon for a more complete check-up after Monday night’s collapse, which he said had nothing to do with the cancer. Doctors there agreed, saying the episode was likely due to the governor standing for an extended period of time, and dehydration.

Dayton said he’ll start undergoing treatment next week and he’s healthy enough to finish the last two years of his current term. The governor is not seeking re-election.

Dayton revealed the news at a Tuesday press conference after he outlined his budget proposal. After going through introductory remarks, the 69-year-old Democrat turned the briefing over to his budget commissioner and took a seat to listen. The governor usually stands on such occasions.

Monday night’s episode raised new questions about Dayton’s health as he is about to turn 70 — his birthday is Thursday — and as he moves into his final two years in office facing a newly GOP-controlled Legislature. He is not seeking re-election.

Dayton’s top staffer said he was OK and planned to return to work Tuesday after he collapsed during his State of the State speech.

Dayton struck his head on a lectern Monday night after stumbling over his words and collapsing roughly 40 minutes into the annual address. He appeared conscious as he was helped into a back room within several minutes, and later walked out of the Capitol on his own.

Dayton’s chief of staff Jaime Tincher said Dayton quickly recovered and returned home to spend time with his son and grandson after a routine check by emergency medical technicians at the governor’s residence in St. Paul. She said Dayton would return to the Capitol Tuesday morning for a planned event to release a detailed budget proposal.

Dayton was hospitalized in February 2016 after he fainted at a hot and crowded event. His office said at the time that he had been feeling pressure in his lower back — he had undergone elective back surgery the previous December — before he lost consciousness. Dayton spent just a day in the hospital, and said afterward he had been treated for dehydration.

In addition, a series of back and hip surgeries in recent years has left him with a permanent limp.

The governor told reporters his prostate cancer diagnosis will not prevent him from doing his duties as governor.

“When I had my hip surgery, I said there are no brain cells in my hip, and as far as I know there are no brain cells in my prostate, either,” Dayton joked.

The governor fell about three-fourths of the way through his speech as he laid out the opening salvo in a brewing battle with Republican legislative majorities over where to bring the state after November’s elections, including his proposal for a state-run public health care option for all Minnesota residents.

Dayton appeared to stumble as he first entered the House chamber, but joked it away, saying he should have attended the walkthrough. But he appeared to lose his place in his remarks roughly 40 minutes into his speech, trailing off in the middle of a sentence before pausing to take a long drink of water from a bottle he had below the lectern.

When he tried to resume his address, he spoke only a few slurred words before his shoulders appeared to shake and he crumbled behind the lectern, striking his head. A frantic voice could be heard over the microphone saying “get him to the ground. Get him to the ground please” as those around Dayton rushed to assist him.

One of those who ran to help the governor was Rep. Jerry Hertaus (R-Long Lake), who is trained as a cardiac nurse.

“I saw that he was distressed, but I saw that he was sitting up and breathing,” Hertaus said.

After 5 minutes: Dayton walked with assistance to a back room, but Hertaus says he declined advice to go to the emergency room to check for a possible stroke.

“You really should, under those kinds of circumstances, go to the emergency room,” Heraus said. “All of us encouraged him to do that, but he wanted to go home. He said he felt fine.”

Daudt and fellow Republican legislative leaders declined to comment on Dayton’s speech, instead only offering their prayers for his health and safety.

“That’s our whole focus right now, just praying for our governor,” Republican Senate Majority Leader Paul Gazelka said.

Dayton is facing an all-Republican Legislature his final two years in office after the GOP took control of the Senate in November and added to their House majority.

Facing a unified GOP front for his final two years in office — Republicans took back control of the Senate and strengthened their House majority in November — Dayton has increasingly looked to the past as he seeks to cement his legacy.

Dayton entered office in 2011 facing a $6 billion budget deficit. After a stalemate with Republican majorities led to a 20-day government shutdown that year, he and Democrats united to control the Capitol in 2013. They raised taxes on the state’s wealthiest earners, increased the minimum wage and legalized same-sex marriage.

The state has posted several years of surpluses, and the governor has pointed to that financial stability as a hallmark of his six years in office, insisting he’ll safeguard against a return to painful budget shortfalls.

“In 2010, I campaigned for governor on the promise of a better Minnesota. Now, and two years from now, I expect to be judged by you, the people of Minnesota, on how well I have kept that promise,” he said during his remarks. “In my first inaugural address, I promised that I would ‘clean up the state’s financial mess.’ I have kept my word.”

Dayton has dealt with several health issues since taking office in 2011. He had surgery on his spine to treat stenosis in both 2012 and 2015. He had a plasma injection in his hip in 2013 after tearing a muscle, and underwent hip surgery a few months later in 2014. He previously fainted at an event in Woodbury in late January of 2016, an incident that was later attributed to increased pressure in his lower back.

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