A 36 year-old mum is celebrating 18 months bowel cancer free thanks to a new UK miracle drug trial – when diagnosed with the killer disease on her son’s first birthday. Zara McCormick was left horrified when told her fatigue and breathlessness, as she and husband Paul celebrated Lewis’s first birthday, were in fact stage 3c bowel cancer with an MSI-H mutation. 

But the project manager, from Tameside, Greater Manchester, was offered  the NEOPRISM trial – where doctors at The Christie are giving patients immunotherapy drug pembrolizumab, instead of chemotherapy, before surgery. Under NEOPRISM, almost 60 percent of patients had no signs of cancer after treatment with pembrolizumab alone, with the rest cancer free after subsequent surgery.

Now thrilled Zara is celebrating more than 18 months of being bowel cancer free all thanks to the clinical trial at The Christie NHS Foundation Trust, a specialist cancer centre in Manchester. 

Zara told the Express: “I didn’t have any of the typical bowel cancer symptoms like blood, so the diagnosis came as a massive shock. 

“At first, I was quite hesitant about going on a trial, but my team at The Christie really helped to put my mind at ease. 

“They took the time to talk me through everything and answer all my questions. 

“They explained that my type of cancer might not respond to chemotherapy – the standard treatment currently available – and gave me all the information I needed to make the right choice for me. 

“By the end of the appointment, I’d decided to go for it.” 

The current bowel cancer standard of care would be surgery,  and then possibly conventional chemotherapy which is likely to be less effective than immunotherapy prior to surgery. 

Zara, whose son is now three years-old, was diagnosed in the same week as Lewis’s first birthday, and had initially put her symptoms – anaemia which was causing fatigue and breathlessness – down to pregnancy. 

However, when they continued after Lewis was born, she went to have some tests at her local hospital and was diagnosed with stage 3c bowel cancer with an MSI-H mutation. 

This type of cancer is very responsive to immunotherapy, so she was referred to The Christie to find out more about the NEOPRISM trial. 

(MSI-H) occurs when mismatch repair (MMR) genes, whose job is to correct errors that happen during cell division, stop functioning properly. Around 10-15% of people with bowel cancer have this mutation. 

Immunotherapy works by stimulating the body’s immune system to identify and fight cancer – and Pembrolizumab is a type of immunotherapy targeted therapy drug called an ‘immune checkpoint inhibitor’. 

It works by keeping cancer cells from suppressing the immune system. This allows the immune system to attack and kill the cancer cells. 

It is currently approved for use in the UK for a wide range of cancers including breast cancer, melanoma, cervical cancer and some types of lymphomas and carcinomas. 

Zara started her three cycles of pembrolizumab in June 2023. She then had a scan, which showed that the tumours in her bowel and lymph nodes had shrunk significantly, and she had surgery to remove part of her bowel. 

She had the operation at The Christie in September, and the subsequent biopsy result showed there were no active cancer cells, only scar tissue, so she’d had a complete response to her treatment. 

Zara remains cancer-free and now has six-monthly scans and yearly colonoscopies at The Christie.

Of her experience, she said: “Although I tolerated the treatment well, it did leave me feeling fatigued, so I’m really focused on getting my fitness back so I can be as active as my little boy is. 

“I’m back at work and looking forward to the little things, like celebrating my 10th wedding anniversary in a couple of years and seeing Lewis start school. I’m also involved in some bowel cancer support groups, helping others like me. 

“I was so well looked after by my team at The Christie, I can’t thank them enough for what they’ve done for me. Anup, my nurse, was particularly brilliant. 

“He was the first person I spoke to at my first appointment and has been there for me every step of the way. Having someone like that there when you’re going through a difficult time makes all the difference. 

“One of the reasons I wanted to share my story is to change the perception that clinical trials are a last resort. For me, this was the first treatment I had, and I’m so glad I said yes. 

“I would encourage other people with cancer to be open-minded about taking part. 

“New treatments wouldn’t be possible without trials, so you’re also helping make things better for other people in the future. There’s something very special about that.” 

Professor Mark Saunders, Zara’s consultant oncologist at The Christie, told us: “It’s brilliant to see that Zara and all the other patients have responded so well to immunotherapy. 

“More trials need to be done to validate the findings, but the results we’ve seen so far are really encouraging. Pembrolizumab is a very effective drug and has the potential to change the lives of a few thousand people diagnosed with this type of bowel cancer in the UK every year.” 

The NEOPRISM trial is still recruiting patients, and over the next few years, researchers will assess overall survival and relapse rates. 

It’s a collaboration between UCL (University College London), UCLH, The Christie, St. James’s University Hospital in Leeds, University Hospital Southampton, and the University of Glasgow. 

It is led and sponsored by University College London (UCL) with funding from pharmaceutical company Merck, Sharp and Dohme, and is being conducted by the CRUK and UCL Cancer Trials Centre. 

The target recruitment is 78 people, and the team hopes to complete recruitment as soon as possible.

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