As my mum fought against breast cancer, I decided I wanted to spend my life seeking it out in others.

My mum was diagnosed following a routine mammogram in 2007. At that point I had started working as a diagnostic radiographer. As she went through treatment – surgery, then chemotherapy and radiotherapy, it started to become clear that I wanted to specialise in breast cancer.

She had a way of talking to me about her treatment that was matter of fact, at times brutally honest, but always reassuring. I realised I wanted to be like her. I wanted to be the person sitting someone down and reassuring them, helping them to feel prepared the way my mum had done for me.

When she was in the midst of her treatment, I knew I wanted to spend my life tackling the disease she was fighting – not just at the point of diagnosis, but all the way through. I chose the disease that had chosen my mum.

After she finished her treatment I started working in mammography image interpretation in a hospital in Oxford and was looking at signing up for a master’s in breast imaging, which would allow me to work as a consultant radiographer.

Five years after her initial diagnosis, my mum found another lump. Her GP dismissed it, but I examined the lump and made sure she went back to the GP and got it thoroughly investigated. As I feared, the cancer had come back. She had more surgery and chemotherapy, but in 2014 she was diagnosed with metastatic bone cancer.

Despite more chemotherapy, the surveillance scans showed that it had spread to her liver and she was given a prognosis of six to nine months.

Mum was determined to enjoy what time she had left. Like me she loved the outdoors and being active. She was a retired PE teacher, so we decided to walk the Devon and Welsh coastlines and she had a wonderful trip to Lundy Island with her closest friends.

A few months after we came home, she went into a hospice in Plymouth and I took unpaid leave to spend time with her.

Those final few weeks were hard. I’d go out for runs along the coast to clear my head and give me strength. By then I’d worked with cancer patients for nearly eight years and I drew strength from those experiences to help me cope.

When my mum died in July 2015, at the age of 68, I really struggled with grief. I couldn’t run, I couldn’t really do anything. Looking back now I don’t remember much about that time; it was a painful blur. I went straight back to work – on reflection I probably needed time, but I was running on automatic. I continued studying for my MSc in breast imaging, using my time in the hospice with mum to write case studies.

Eighteen months after she passed away, I got my dream job as a consultant breast radiographer at the Royal Marsden hospital in central London.

Every day I meet patients like my mum and families just like my sister and me. I see women who, hopefully, following an ultrasound and mammogram, can be told they don’t have cancer. Then there are obviously days when I have to give the news that it is cancer.

Sometimes, I’m able to reassure patients that we’ve caught it early, that they’ve followed the correct procedures by going to see their GP and that they have plenty of treatment options available to them. Other times I might have to say that the treatment isn’t working, and explain what the scans might show.

Thanks to my mum’s direct approach, I’m not scared to talk to people about how they’re feeling, and I try to reassure them the way she did me. I can see they’re anxious and, like everyone at the Royal Marsden, I do my best to ensure they have the very best care possible.

I’m running the London Marathon on Sunday in memory of my mum and for the Royal Marsden Cancer Charity, which funds so much of the research, treatment and care where I work. The training has forced me to take up running again for the first time since mum was in the hospice, and it’s changed my mood so much.

I know on the day it’s going to be really emotional but I just hope that mum is looking down on me and feeling proud, not just of me running the marathon but of the person I have become.

Briony Bishop is fundraising for the Royal Marsden Cancer Charity.

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