PEOPLE first confirmed that the star had been hospitalized in Florida with a mystery illness on Jan. 12 after experiencing pain all over his body, according to TMZ.
"Dustin is in the hospital and the medical teams are doing tests to find out more," a rep for Diamond told PEOPLE at the time. "Everyone is hoping for a speedy recovery."
Just two days later, on Jan. 14, Diamond's team confirmed his cancer diagnosis.
"We can confirm that Dustin does have cancer. It's very serious, though we are still waiting for more details, which we will have shortly," his rep told PEOPLE at the time, adding, "He's in a lot of pain."
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Diamond's rep told Entertainment Weekly at the time that the actor was "undergoing chemo" and would remain at the hospital for "at least another week." The rep said Diamond also had "shingles, so he's been in a lot of pain."
"By next week, we'll have a much better understanding of the severity of his condition and what treatments he will need so that he's comfortable," the rep told EW, adding that when he first arrived at the hospital, Diamond was "was fading in and out, feeling sleepy and tired."
On Jan. 21, Diamond's rep confirmed to PEOPLE that he had started chemotherapy specifically for stage 4 small cell carcinoma, a cancer that commonly occurs in lungs but can also manifest in the prostate or gastrointestinal tract.
A second round of chemotherapy was being scheduled and Diamond was also set to begin physical therapy in the near future, according to NBC News. "Dustin is looking forward to spending more time with his girlfriend, playing his bass guitar/video games, as well as making videos for his fans on social media," Diamond's rep told the outlet at the time.
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Less than two weeks later, on Monday, Diamond's rep confirmed the tragic news of his death in a statement to PEOPLE: "We are saddened to confirm of Dustin Diamond's passing on Monday, February 1st, 2021 due to carcinoma. He was diagnosed with this brutal, relentless form of malignant cancer only three weeks ago. In that time, it managed to spread rapidly throughout his system; the only mercy it exhibited was its sharp and swift execution. Dustin did not suffer. He did not have to lie submerged in pain. For that, we are grateful."
Continuing, the statement acknowledged Diamond's "history of mishaps" over the years, but attributed the actor's actions to his own history of "turmoil and heartache."
"In actuality, Dustin was a humorous and high-spirited individual whose greatest passion was to make others laugh," the statement read. "He was able to sense and feel other peoples' emotions to such a length that he was able to feel them too — a strength and a flaw, all in one."
It concluded, "Dustin Diamond was a character in and of himself: an unpredictable spitfire who always left us shocked, but never left us bored. We are thankful he trusted us enough to share his genuine, authentic self with our team. We wish you knew him in the way that we did. We please ask that you give room for privacy to our team and Mr. Diamond's family during this tragic time, as we grieve and remember the memories spent together. This loss is as much stinging as it is sudden."
RELATED: PEOPLE Every Day Discusses Dustin Diamond's Death
Tributes to the late star poured in from Diamond's Saved by the Bell costars after the news of his death broke. (Diamond, who was the only one of the core six cast members not to return for the recent Peacock reboot, is also the only one of the six to have appeared in every other iteration of the show, including Good Morning, Miss Bliss; Saved by the Bell: The College Years and Saved by the Bell: The New Class.)
"I was with him for 11 years, since he was 11 years old. I had no idea he was that young when I hired him!" original Saved by the Bell creator Peter Engel told PEOPLE in an exclusive statement, calling Diamond — who played the goofy-yet-lovable Samuel "Screech" Powers on the series and its various spinoffs — "a comedy genius."
"The boy was brilliant," Engel continued. "I've been known for not letting anyone change my words as a writer and he would come up and say, 'Let me try it this way,' and nine out of 10 times, I would end up doing it his way. When we were shooting the Wedding in Las Vegas movie, I would ruin a scene by laughing so hard."
"I loved him, and he will forever be Screech to me. That character will live on forever," he added.
"I am deeply saddened by the news of my old co-star @realdustindiamond passing," she wrote. "Life is extremely fragile and it's something we should never take for granted. God speed Dustin."
"Dustin, you will be missed my man," added Mario Lopez (A.C. Slater) on Instagram, sharing photos from the duo's time on the show, as well as their 2016 interview — Diamond's first following his release from jail after being found guilty of disorderly conduct and carrying a concealed weapon. "The fragility of this life is something never to be taken for granted. Prayers for your family will continue on."
Mark-Paul Gosselaar, who played Zack Morris on the show, said in a statement to PEOPLE, "I'm deeply saddened to hear of the passing of Dustin Diamond, a true comedic genius. My sincere condolences to his family and friends. Looking back at our time working together, I will miss those raw, brilliant sparks that only he was able to produce. A pie in your face, my comrade."