My Mounjaro weight-loss jab helped me discover I had one of the UK's rarest cancers

A mum has been diagnosed with the UK's rarest, incurable cancer after suffering chest pain she thought was from Mounjaro weight-loss jabs.

Dawn Clegg, 51, began suffering from the pain in late March this year after taking the jabs which helped her deal with her diabetes.

But after having several X-rays at the hospital, shadows were found on her lungs, kidneys, and breast and she was later diagnosed with a soft-tissue cancer known as sarcoma.

She was told the cancer on her breast and kidney were benign, but the one on her lungs was sarcoma which makes up just one per cent of all known cancers.

There are more than 100 known sarcomas doctors have been unable to precisely identify the type Dawn has meaning there is no treatment available to help her.

Now her heartbroken husband Arron Clegg, 51, looks to hold a ‘living wake’ in November to celebrate the life of his wife, who has Britain's rarest cancer after Dawn was given less than a year to live.

Dawn Clegg, 51, has been diagnosed with the UK's rarest, incurable cancer after suffering chest pain she thought was from Mounjaro weight-loss jabsplaceholder image
Dawn Clegg, 51, has been diagnosed with the UK's rarest, incurable cancer after suffering chest pain she thought was from Mounjaro weight-loss jabs | NW

Arron said: "She went to Lancaster Hospital A&E at the end of March with chest pains which she thought were a side effect of Mounjaro which she was taking to help with her diabetes.

"X rays showed shadows on lung, kidney and breast.

"We were devastated on hearing news of cancer in 3 areas - there is no cure and she is now terminal.

"The wake will mean she can spend quality time with friends and family whilst still alive rather than after the funeral that way she can see how much people care about her."

Dawn had been taking Mounjaro weight loss jabs to help with her diabetes but began suffering from a tight chest which she initially thought was a side effect.

In late March Dawn went to Lancaster Hospital A&E with hopes to find out what was causing her chest pain.

She had multiple X-rays which found shadows in her lungs, breasts, and kidney.

But the next day Dawn revealed she "called back" to hospital were they were informed the shadows were cancerous.

She then had some more tests which showed the cancer on her breast was benign and her kidney "wasn't a big issue".

But she was given the "devastating" news that the cancer on her lungs was sarcoma.

Dawn Clegg, 51, with husband Arron before she was diagnosed with the UK's rarest, incurable cancer after suffering chest pain she thought was from Mounjaro weight-loss jabsplaceholder image
Dawn Clegg, 51, with husband Arron before she was diagnosed with the UK's rarest, incurable cancer after suffering chest pain she thought was from Mounjaro weight-loss jabs | Arron Clegg / SWNS

Sarcoma is a rare type of cancer that develops in the supporting tissues of the body, including bone, cartilage, tendons, fat, and muscle.

Arron said: "The doctors don't even know what type of sarcoma it is four months later.

"Sarcoma makes 1% of known cancers and on top of that there are over 100 sarcomas so finding right treatment is extremely hard.

"She is now terminal and there is a high chance she won't make her 52nd birthday next year."

Dawn began receiving chemotherapy at Clatterbridge in Liverpool but Arron has told "there is more chance of it not working then slowing it down".

Following Dawn's diagnosis Arron is now hoping to organise a ‘living wake’ – a joyful celebration of her life surrounded by friends and family while she is still with them.

Arron hopes to invited around 100 of his wives closest family and friends to enjoy a final evening together.

Arron said: "Dawn means the world to me.

"We went to school together and started dating after we found each other years later and have been married nearly 10 years.

“Dawn is an amazing person; not very patient and yet with this illness she has surprised us both with her patience whilst they tried to find a treatment.

"She is the best person I ever knew and the wake will mean the world to her."

Dawn Clegg, 51, before she was diagnosed with the UK's rarest, incurable cancer after suffering chest pain she thought was from Mounjaro weight-loss jabsplaceholder image
Dawn Clegg, 51, before she was diagnosed with the UK's rarest, incurable cancer after suffering chest pain she thought was from Mounjaro weight-loss jabs | Arron Clegg / SWNS

When the time comes, this will be followed by a funeral at Lancaster and Morecambe Crematorium, where Dawn will be laid to rest near her late daughter Isobel, who died in childbirth.

Dawn, a receptionist with Bay Medical Group, also has a son, George, who is 19 and currently at university in Leeds, where he is studying film production.

Since Aaron has started a crowdfunding to help pay for the costs of the wake and funeral which will take place on November 29 2025.

You can support Arron’s cause online here: https://www.gofundme.com/f/to-the-best-person-i-ever-knew-my-wife-dawn-clegg

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