What we know and don't know about the Princess of Wales's cancer diagnosis

The Prince and Princess of Wales have said they are "enormously touched" by the support they have received in the wake of Kate's cancer diagnosis.

On Friday, the princess revealed she was undergoing preventative chemotherapy. Her announcement was met with a wave of support after weeks of speculation and rumours surrounding her lack of public appearances since Christmas Day.

Kensington Palace said in a statement on Saturday evening: "The Prince and Princess are both enormously touched by the kind messages from people here in the UK, across the Commonwealth and around the world in response to Her Royal Highness' message.

"They are extremely moved by the public's warmth and support and are grateful for the understanding of their request for privacy at this time."

That request for privacy came after social media had been awash with theories about her whereabouts, with conspiracies further fuelled when Kensington Palace released a Mother's Day photograph of Kate and her three children – Prince George, Princess Charlotte and Prince Louis – which it later emerged had been edited.

Kate, 42, put an end to the speculation with a video statement released at 6pm on Friday, in which she said: "It has been an incredibly tough couple of months for our entire family, but I've had a fantastic medical team who have taken great care of me, for which I am so grateful.

"In January, I underwent major abdominal surgery in London and at the time, it was thought that my condition was non-cancerous. The surgery was successful. However, tests after the operation found cancer had been present.

"My medical team therefore advised that I should undergo a course of preventative chemotherapy and I am now in the early stages of that treatment."

Meanwhile, the Duke and Duchess of Sussex reached out privately to Kate and William following her announcement, the BBC reported on Saturday. Earlier, Harry and Meghan had issued a statement saying: "We wish health and healing for Kate and the family, and hope they are able to do so privately and in peace."

The shocking update about Kate's health comes more than a month after King Charles revealed his own cancer diagnosis.

Buckingham Palace announced in early February that the monarch had been diagnosed with an unspecified form of cancer, which was found after a routine hospital procedure to treat an enlarged prostate.

Princess of Wales is undergoing preventive chemotherapy

The announcement about Kate's condition revealed that her was only discovered after her abdominal surgery in January. She initially underwent the procedure for a "non-cancerous" condition, but further tests found that cancer was present.

She has been undergoing "preventative chemotherapy" and Kensington Palace is confident she will make a full recovery.

In her message, which was filmed on Wednesday 20 March in Windsor by BBC Studios, the princess described the news as a "huge shock" for her and William. She said they "have been doing everything we can to process and manage this privately for the sake of our young family".

"It has taken me time to recover from major surgery in order to start my treatment," she added. "But, most importantly, it has taken us time to explain everything to George, Charlotte and Louis in a way that is appropriate for them, and to reassure them that I am going to be okay."

Gemma Peters, chief executive of the Macmillan Cancer Support charity, said: "Many will be relating to the Prince and Princess of Wales at this time. Some of the first thoughts parents have after being diagnosed with cancer are how it may affect their children, and whether talking to them about it will make them worry but it is important to give them the chance to talk openly about their fears."

When talking to children about cancer, the charity advised people to be honest, use simple language, answer their questions and keep information relevant to the current situation and not what may happen in the future.

On 17 January, Kensington Palace announced that Kate underwent abdominal surgery and would remain hospitalised for two weeks. The statement suggested she would return to public duties around Easter on 31 March.

It said the princess underwent "planned abdominal surgery" at The London Clinic, just a few days after she celebrated her 42nd birthday.

In her announcement Kate said her surgery was successful but tests after the operation found cancer had been present, so she had been advised to undergo a course of preventative chemotherapy of which she is now in the early stages.

According to Dr Yuman Fong, a surgeon at City of Hope cancer centre in Southern California, while it is rare to find cancer after surgery for a noncancerous problem, it does happen in about 4% of such surgeries.

Dr Fong told the Associated Press: “That 4% figure represents someone who’s going to the operating room for what is thought to be benign disease” such as a procedure to remove the gallbladder or ovarian cysts.

Why is Kensington Palace sharing the news now?

The announcement comes after weeks of speculation weeks of speculation online around Kate's whereabouts, with a number of unsubstantiated rumours and theories about where she is generating headlines and discussions all over the world.

But it is understood Kate wanted time and space to come to terms with diagnosis, recover from surgery and then begin her pathway to recovery.

Kensington Palace said that Kate wanted to keep the details of her condition private in order to "maintain as much normality for her children as possible". The palace said: “The princess wanted to share this information when she and the prince felt it was right for them as a family.”

William and Kate also wanted to be able to tell their children at the right time and allow them to understand and process the news before it became public, and decided to make the announcement now the children are away from school on their Easter holidays.

Earlier this week, the British privacy and data protection watchdog, the Information Commissioner's Office, says it is probing a report that at least one staff member at London Clinic, where Kate had surgery, tried to access her medical records.

According to The Mirror, the hospital initiated an internal investigation. Kensington Palace declined to comment on the alleged breach.

The palace has said it will "only provide updates on Her Royal Highness' progress when there is significant new information to share".

What kind of cancer does the Princess of Wales have?

It has not been revealed exactly what type of cancer Kate was diagnosed with, nor what stage it was discovered at. However, as the palace is confident she will make a full recovery, it is hoped that the cancer was found in an early stage.

Kensington Palace has said no further medical information will be shared, and that Kate has a right to medical privacy just like everyone else.

While the Princess has confirmed she started a course of preventative chemotherapy in late February, it's not known exactly what this process involved or how long it will last for.

Her statement also did not clarify exactly when Kate would return to public life. She said she is still in the "early stages" of the course of preventative chemotherapy and will be focusing on her health.

This may mean she will not be seen at Easter, which is now less than two weeks away, as was initially announced.

It is unknown how long the princess has been dealing with illness. She underwent the major abdominal surgery for a condition that was thought to be non-cancerous, which suggests that although the cancer was not diagnosed, Kate may have been suffering for some time before.

In her video message, Kate offered support to others affected by cancer, saying: “For everyone facing this disease, in whatever form, please do not lose faith or hope. You are not alone.”