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Chadwick Boseman -

When actor Chadwick Boseman was diagnosed with colon cancer in 2016, he kept it private. He carried on working as an actor as well as supporting cancer charities.

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Chadwick Boseman -

By 2020, Boseman's cancer had progressed and he sadly passed in August of that year. His final film 'Ma Rainey's Black Bottom' (2020) was released posthumously to critical acclaim.

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Gene Wilder -

After actor Gene Wilder passed away in August 2016, his family revealed that he had been suffering from Alzheimer's disease for the previous three years.

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Gene Wilder -

According to his nephew, the 'Willy Wonka and the Chocolate Factory' (1971) star kept his condition a secret in order to protect his young fans, because "he simply couldn’t bear the idea of one less smile in the world."

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David Bowie -

When the news broke of David Bowie's death in January 2016, the world was left reeling. Hardly anybody knew that he had been suffering from liver cancer for 18 months before his death.

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David Bowie -

The iconic musician apparently told his loved ones that he wanted to go "without any fuss" and sources suggest his body was cremated without even family or friends present.

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Steve Jobs -

In 2011, Apple cofounder Steve Jobs died from respiratory arrest as a result of a relapse of his pancreatic cancer. Sources suggest he had been battling the disease for nearly 20 years.

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Steve Jobs -

Jobs's battle with pancreatic cancer was extremely private and very few people knew. Former Disney CEO Bob Iger is thought to be one exception to that.

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Freddie Mercury -

Nowadays it is common knowledge that Queen front man Freddie Mercury died of AIDS-related complications, but when he was suffering from the disease very few people knew.

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Freddie Mercury -

There were reports that the star was battling the disease, but he denied them all. The public and his fans knew nothing of his struggle, although the other band members were in on the secret.

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Robin Williams -

Shortly after Robin Williams killed himself in 2014, his widow revealed that her husband had been diagnosed with Parkinson's disease in the period before his death.

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Robin Williams -

In her statement, she described how she felt that the diagnosis had been a factor in his death. An autopsy revealed, however, that Williams had been suffering from Lewy body dementia, not Parkinson's.

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Alan Rickman -

The public was left shocked when news broke of Alan Rickman's death in January 2016. The 'Harry Potter' actor had kept his battle with cancer very much under wraps.

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Alan Rickman -

Actor Bill Paterson spoke after Rickman's death about how he had "no inkling of the seriousness" of his death, despite having visited him just two weeks before.

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Nora Ephron -

Acclaimed filmmaker Nora Ephron, who is best known for her romantic comedies, died in 2012 after a battle with cancer.

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Nora Ephron -

The battle had apparently been a long one, although hardly anyone knew. Sources suggest even some of her closest friends were shocked to hear the news.

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Jackie Collins -

Romance novelist Jackie Collins, whose books have sold over 500 million copies and have been translated into over 40 languages, died of breast cancer in 2015. 

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Jackie Collins -

Collins's death marked the end of her six-year battle with breast cancer. And yet sources suggest that no one knew of her diagnosis, apart from herself and her two daughters.

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Michael J. Fox -

Nowadays Michael J. Fox is one of the most vocal celebrity sufferers of Parkinson's disease. He is an important advocate for finding a cure for the neurological disease.

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Michael J. Fox -

However, sources suggest that he kept his diagnosis secret for years: he was apparently diagnosed as early as 1990, but did not share the news with his fans until 1998.

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Kathy Bates -

In 2013, veteran actress Kathy Bates opened up about her battles with cancer. She had a double mastectomy after doctors found a tumor in 2012.

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Kathy Bates -

She also survived a battle with ovarian cancer in 2003, which until 2013 she had kept from the public. She told the press that her experience in 2003 shaped her double mastectomy decision.

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Michael Douglas -

Michael Douglas did not keep his cancer a complete secret, but he didn't let on quite how serious it was. At one point he was at risk of losing his tongue and jaw.

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Michael Douglas -

The public knew that the actor was undergoing surgery to remove cancerous tumors, but he didn't reveal the severity of the situation until after he had recovered.

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Charlie Sheen -

In 2015, 'Two and a Half Men' star Charlie Sheen revealed on the 'Today' show that he is HIV positive. But the diagnosis was not new, as he'd already had it for four years.

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Charlie Sheen -

In the exclusive, Sheen said that he wanted to make the announcement to end the "barrage of attacks and of sub-truths and very harmful and mercurial stories that are about me."

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Jennifer Saunders -

British actress and comedian Jennifer Saunders was diagnosed with breast cancer in 2009, but she did not speak publicly about it until after she had recovered.

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Jennifer Saunders -

The 'Absolutely Fabulous' and 'French and Saunders' star, who apparently always hid her chemo-related hair loss with a wig, told her story in her 2013 autobiography 'Bonkers: My Life in Laughs.'

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Avril Lavigne -

In 2015, singer Avril Lavigne revealed that she had recently recovered from a serious case of Lyme disease, which had kept her bedridden for five months.

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Avril Lavigne -

The 'Sk8er Boi' musician was apparently bitten by a tick at some point during the spring of 2014, and went on to suffer her serious case of Lyme disease in silence.

Sources: (Ranker) (People) (BBC)

See also: Celebrities open up about their scars

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