{"id":12699,"date":"2026-02-12T14:24:19","date_gmt":"2026-02-12T15:24:19","guid":{"rendered":"http:\/\/curiousdrive.com\/?p=12699"},"modified":"2026-02-18T21:33:45","modified_gmt":"2026-02-18T21:33:45","slug":"i-thought-i-was-resistant-to-mounjaro-but-i-had-a-rare-12kg-tumour","status":"publish","type":"post","link":"http:\/\/curiousdrive.com\/index.php\/2026\/02\/12\/i-thought-i-was-resistant-to-mounjaro-but-i-had-a-rare-12kg-tumour\/","title":{"rendered":"I thought I was resistant to Mounjaro \u2014 but I had a rare 12kg tumour"},"content":{"rendered":"
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Becki thought she was just overeating, but that wasn’t the case at all (Picture: Becki Ward\/SWNS)<\/figcaption><\/figure>\n

Becki Ward had never felt comfortable with her weight so, like 1.6 million other adults in the UK, she began taking Mounjaro<\/a> in October 2024.<\/p>\n

‘At first it was working well, and supressing my appetite, but then I realised I wasn’t losing weight as fast as everybody else,’ the now 33-year-old trainee health<\/a> practitioner explains.<\/p>\n

‘Some people were losing half-a-stone a week, and I was only losing one or two pounds in the same amount of time.<\/p>\n

‘I’ve always struggled with my weight, so I thought it must just be me.’<\/p>\n

What Becki didn’t know at the time was that she had a 12kg cancerous tumour<\/a> growing in her stomach, due to an extremely rare form of cancer<\/a> only two UK hospitals are able to treat.<\/p>\n

Pseudomyxoma peritonei<\/a> (PMP) affects just 400 new patients per year in Britain, and typically begins as a small growth in your appendix, called a polyp, but it can also start in your bowel or ovaries (although this is even rarer).<\/p>\n

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Becki in hospital after surgery to remove her large tumour (Picture: Becki Ward\/SWNS)<\/figcaption><\/figure>\n

After a few months of blaming herself for the weight loss jabs<\/a> not working, Becki began suffering with unpleasant new symptoms.<\/p>\n

‘I assumed it wasn’t working because I’m in my 30s, I was lazy, or I was overeating,’ Becki, from Great Yarmouth, says.<\/p>\n

‘Then I started to get night sweats and stomach pains. I’d read on the news about people getting pancreatitis from Mounjaro<\/a> and I started panicking and thought that’s what I had.’<\/p>\n

Mounjaro manufacturer Eli Lilly<\/a> lists acute pancreatitis as an ‘uncommon’ side effect that may affect up to 1 in 100 people, increasing the detail in it’s information leaflet back on October 31, 2025.<\/p>\n

Becki went to the doctors to get blood tests, and to check her organs, but she was shocked when tumour markers flagged up. Doctors initially thought Becki had ovarian cancer<\/a> but carried out more tests to be sure.<\/p>\n

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\n\t\t\t\tPseudomyxoma peritonei (PMP)\t\t\t<\/h2>\n
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PMP usually grows slowly, but it can eventually spread into other parts of the tummy, and the peritoneum, which lines the abdomen.<\/p>\n

These cancer cells make a mucus that collects in the abdomen as a jelly-like fluid called mucin. This has earned the cancer the nickname ‘jelly belly’.<\/p>\n

PMP doesn’t spread to other parts of the body like other cancers, but it will spread inside the tummy.<\/p>\n

This particular cancer is more common in women than men, and can be confused with ovarian cancer, which can also cause a swollen abdomen.<\/p>\n

Symptoms of PMP are:<\/h3>\n