Hannah Sheridan was enjoying a normal night out at the pub when her friends pointed out a 'huge lump' on her neck - months later she discovered it was cancer.
Ms Sheridan, 26, from London, was already struggling with a slew of health concerns which had affected her hormones and digestion, but didn't immediately connect them to the lump.
She said: 'When I felt the lump while with my friends, I tried to keep calm.
'I was hoping they would say it was all in my head and there was nothing there.
'They tried to reassure me that it'd be nothing serious; though I couldn't help but panic.'
She had already been experiencing problems with her hormones and stomach, which were diagnosed as polycystic ovary syndrome (PCOS) and irritable bowel syndrome (IBS).
However, her menstrual issues - which have since calmed down since having part of her thyroid removed - might have been related to the rogue organ.
The thyroid is one of the major hormone centres in the body and helps control the ovaries, so when it is out of sync it throws off estrogen and progesterone, disrupting ovulation and causing heavy bleeding - mimicking symptoms of PCOS.
Similarly, the thyroid plays a role in digestion, and studies have linked thyroid cancer with inflammatory bowel diseases.
Ms Sheridan also experienced a 'throbbing' pain at the back of her neck that wouldn't shift.
She said: 'I was told that it was just due to my muscles being tense.
'I had also suffered from constantly fluctuating weight, as well as acid reflux.'
In May 2025, the lump was confirmed to be on her thyroid and, two weeks later, Ms Sheridan was placed on the suspected cancer list.
A biopsy and ultrasound were carried out, alongside a blood test, though her results from the latter came back 'normal'.
A month on, she met with a surgeon face-to-face who confirmed it was papillary thyroid cancer (PTC), which accounts for 75 to 85 per cent of all thyroid cancers, making it the most common type.
The other main type of cancer in the butterfly-shaped gland, which is positioned just in front of the voice box, is follicular thyroid cancer (FTC).
Thankfully, PTC has high cure rates after being treated with surgery and radiotherapy.
According to Cancer Research UK, thyroid cancer accounts for just 1 per cent of all cancers in the UK, with around 4,000 new cases diagnosed every year.
Of these, there are roughly 440 deaths; 84 per cent of people live for a decade or more after being treated for the disease.
PTC is slow-growing and is most common in women aged between 30 to 50. Symptoms can include difficulty swallowing and swollen lymph nodes.
There has been an increase in cases of thyroid cancer, particularly in younger people, but experts previously told the BBC that this was down to more robust screening programmes and advanced technologies catching the disease earlier than ever before.
On June 3, the right side of Ms Sheridan's thyroid was removed and it was a waiting game to see what would happen next.
She said: 'I was in complete pieces.
'After the dust had settled, I began to feel strangely calm.
She added: 'Since the operation, the intense neck pain I had been feeling has vanished completely.
'I had no choice but to cope with whatever was about to come my way, though.'
In August, she jetted off to Ibiza to celebrate with her friends when she got a devastating phone call that the tumour had grown.
It meant that Ms Sheridan was left with no choice but to have her entire thyroid removed as well as radiotherapy - a procedure she is currently waiting on.
Since the initial operation, she has seen her other health woes improve. She said: 'My periods are regular for the first time in my life.
'Doctors kept dismissing me with other conditions.
'But, deep down, I knew something much worse was going on.
'None of my symptoms had been taken seriously until it was too late.
'I never knew I had thyroid problems as my hormone issues were always fobbed off and deemed normal.
'I've got to be on replacement medication for life now. It's better to be safe than sorry, though.'
Ms Sheridan has found the last few months both physically and emotionally taxing.
'I've not been sleeping well and feel like I've been left in the dark a lot,' she said.
'But I'm so glad I trusted my instincts and pushed for an answer.
'Women's health isn't taken seriously enough.
'It's time to start listening – as, otherwise, it might be too late.'
It's not just cancer which can cause catastrophic issues with the thyroid.
At least one in 20 people in the UK have a disorder of the thyroid, which produces two key hormones — triiodothyronine (T3) and thyroxine (T4) — which help regulate key body functions, including heart rate, temperature and mood.
An overactive thyroid (hyperthyroidism) is when levels of these hormones are too high, causing symptoms such as palpitations, rapid weight loss, sweating and itching.
But much more common is hypothyroidism, where the gland produces too few hormones, leading to weight gain, fatigue, feeling the cold, constipation and dry skin and hair.
Women are ten times more likely to be affected than men, although it’s not clear why — and the most common trigger for both thyroid problems is an auto-immune condition, where the body mistakenly attacks the thyroid tissues.